Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly di...Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each.In group 1,each tooth was hemisected into two halves.One half was assigned to control subgroup 1,which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing.In group 2,the teeth were also hemisected into two halves.One half was assigned to control subgroup 2,which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer.Microtensile bond strength was immediately tested after specimen preparation.Results When the adhesive was applied three times before light curing,the bond strength of the experimental subgroup 1(n=33,57.49±11.61 MPa) was higher than that of the control subgroup 1(n=31,49.71±11.43 MPa,P<0.05).When using the technique of applying multiple layers of adhesive with light curing each successive layer,no difference of immediate bond strength was observed between the control subgroup 2 and the experimental subgroup 2(P>0.05).Conclusion Multiple coatings of one-step self-etching adhesive can increase the immediate bond strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.展开更多
Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 gro...Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 groups. In group 1, each tooth was hemisected into 2 halves. One half was assigned to the control subgroup 1, which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instruc- tions; the other half was assigned to experimental subgroup 1, in which the adhesive was applied three times before light curing. In group 2, one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instructions; for the other half, three layers of adhesive were applied with each successive layer of light curing. Specimens were stored in 0.9% NaC1 containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis. Results When the adhesive was applied three times before light curing, the bond strength of the ex- perimental subgroup 1 was significantly higher than that of the control subgroup 1 （47.46__＋13.91 vs. 38.12＋11.21 MPa, P〈O.05）. When using the technique of applying multiple layers of adhesive with each successive layer of light curing, no difference was observed in bond strength between the control subgroup and the experimental subgroup （39.40＋8.87 vs. 40.87-＋9.33 MPa, P〉O.05）. Conclusion Multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.展开更多
Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor th...Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping.Traditional pulp capping agent,calcium hydroxide,may not prevent microleakage.Selfetching system is a newly developed adhesive system,which could provide less microleakage and would not break down or dissolve,preventing the oral fluids and bacteria from the pulp along the cavity wall.This may reduce such clinical problems as postoperative sensitivity,secondary caries and marginal discoloration.Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response,with negative bacterial staining.Inclusion of antibacterial components into self-etching system,such as 12-methacryloyloxydodecylpyridinium bromide(MDPB)may inhibit bacteria and provide better clinical effects.It is speculated that using the self-etching adhesive system containing the antibacterial agent,such as MDPB,to the dental pulp directly or indirectly,may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.展开更多
Nature evolves soft but structural architectures with typical wet/lubricous/adhesive behavior,as well as tunable interface functionalities,such as superhydrophilicity,superhydrophobic,superlubricity,high adhesion,etc....Nature evolves soft but structural architectures with typical wet/lubricous/adhesive behavior,as well as tunable interface functionalities,such as superhydrophilicity,superhydrophobic,superlubricity,high adhesion,etc.In order to simulate this,new chemistry modification methods,novel polymers materials and advanced manufacture techniques are developed for engineering diverse bioinspired wet/lubricous/adhesive soft matter systems.This review focuses on two typical interface functionalities of soft architectures in nature:wet lubrication and wet adhesion.Correspondingly,systematic summaries of recent progress for constructing bioinspired wet/lubricious/adhesive soft matter systems are proposed,including the surface grafting methods to construct hydrophilic wet lubrication surfaces,the bionic design of mechanically robust and structured soft matter lubrication materials,the novel preparation of high-performance biomimetic wet adhesion materials,and the advanced manufacture of 3D soft matter-based wet/lubricious devices.Subsequently,the current strategies relying on diverse regulation factors including surface hydration/roughness,surface intrinsic states,bulk mechanics,as well as multi-factors synergy,are introduced and discussed for achieving dynamic friction or adhesion control of bioinspired soft matter lubrication/adhesion systems.Finally,the existing problems,challenges and future development directions of bioinspired wet/lubricious/adhesive soft matter materials and devices are discussed.This review provides clear guidance for designing bioinspired soft matter-based lubrication,adhesion,or adhesion-lubrication switchable systems,and would act as a necessary research handbook in the field of surface/interface wettability engineering,bioengineering,medical devices,soft robotics,etc.展开更多
Objective: In the Healthy Child Action Enhancement Program (2021-2025), it is proposed to ensure the safety and health of newborns and to promote high-quality development of health. Our department established risk ass...Objective: In the Healthy Child Action Enhancement Program (2021-2025), it is proposed to ensure the safety and health of newborns and to promote high-quality development of health. Our department established risk assessment criteria for medical adhesives in neonates by applying the best evidence in the management program for the reduction of medical adhesive-associated skin injuries in neonates, in terms of the use and removal of adhesives. Methods: A systematic search and quality assessment of topics related to medical adhesive-related skin injury in neonates was conducted to summarize the best evidence and to conduct a quality review in the neonatal unit. Results: After 2 rounds of review, medical and nursing staff in the neonatal unit had a 98% compliance rate for the knowledge of neonatal medical adhesive-related skin injury and a satisfactory compliance rate for the other 9 indicators;after the application of the evidence, the incidence of neonatal medical adhesive-related skin injury was significantly lower than that before the application of the evidence, and the differences were statistically significant (P Conclusion: The application of the best evidence-based management program in neonatal medical adhesive-associated skin injury can reduce the incidence of neonatal medical adhesive-associated skin injury, reduce neonatal infections, and improve the integrity of the protective skin barrier in neonates.展开更多
Sluggish storage kinetics is considered as the main bottleneck of cathode materials for fast-charging aqueous zinc-ion batteries(AZIBs).In this report,we propose a novel in-situ self-etching strategy to unlock the Pal...Sluggish storage kinetics is considered as the main bottleneck of cathode materials for fast-charging aqueous zinc-ion batteries(AZIBs).In this report,we propose a novel in-situ self-etching strategy to unlock the Palm tree-like vanadium oxide/carbon nanofiber membrane(P-VO/C)as a robust freestanding electrode.Comprehensive investigations including the finite element simulation,in-situ X-ray diffraction,and in-situ electrochemical impedance spectroscopy disclosed it an electrochemically induced phase transformation mechanism from VO to layered Zn_(x)V_(2)O_5·nH_(2)O,as well as superior storage kinetics with ultrahigh pseudocapacitive contribution.As demonstrated,such electrode can remain a specific capacity of 285 mA h g^(-1)after 100 cycles at 1 A g^(-1),144.4 mA h g^(-1)after 1500 cycles at 30 A g^(-1),and even 97 mA h g^(-1)after 3000 cycles at 60 A g^(-1),respectively.Unexpectedly,an impressive power density of 78.9 kW kg^(-1)at the super-high current density of 100 A g^(-1)also can be achieved.Such design concept of in-situ self-etching free-standing electrode can provide a brand-new insight into extending the pseudocapacitive storage limit,so as to promote the development of high-power energy storage devices including but not limited to AZIBs.展开更多
More than a century after its initial synthesis,urea-formaldehyde(UF)resins still have dominant applications as adhesives,paints,and coatings.However,formaldehyde in this industry produces formaldehyde emissions that ...More than a century after its initial synthesis,urea-formaldehyde(UF)resins still have dominant applications as adhesives,paints,and coatings.However,formaldehyde in this industry produces formaldehyde emissions that are dangerous to health.Scientists have spent the last decade replacing formaldehyde and phenol with environmentally friendly substances such as glyoxal and tannin to create bio-based adhesives.This review covers recent advances in synthesizing glyoxal tannin-based resins,especially those made from sustainable raw material substitutes and changes made to synthetic processes to improve mechanical properties.The efficacy of using tannin-glyoxal adhesives in producing wood-based composites has been proven.The glyoxylate reaction forms cross-linked bridges between the aromatic sites of the tannin and glyoxal molecular structures.Glyoxal tannin adhesive with a greater percentage of glyoxal than tannin will produce an adhesive with better characteristics.The gel time reduces as the hardener concentration rises from 7.5%to 15%when glyoxal is used in adhesives.However,excessive amounts of glyoxal will result in a decrease in viscosity values.Glyoxal exhibits faster delivery degradation when it reaches a maximum temperature of approximately 130°C,although it initiates the curing process slightly slower at 110°C.Adding glyoxal to tannin-based adhesives can improve the mechanical properties of composite boards.The wet shear strength of the resulting plywood is increased by 105.4%with the addition of 5-weight percent tannin-based resin with glyoxal as a cross-linker in Soy Protein Adhesive.With glyoxal as a hardener,the panels produced showed good internal bond strengths(>0.35 MPa)and met the international standard specifications for interior-grade panels.展开更多
Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol...Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol for the synthesis of non-isocyanate polyurethane(NIPU)adhesives to substitute current polyurethane(PU)adhesives that have been synthesized with toxic isocyanate and polyols.Crude hardwood kraft lignin(C-HKL)was extracted from black liquor from a pulp mill followed by acetone fractionation to obtain acetone soluble-HKL(AS-HKL).Then,C-HKL,AS-HKL,and softwood sodium lignosulfonate(LS)were used for the synthesis of technical lignin-based NIPU adhesives through carbonation and polyamination and silane as a cross-linker.Their adhesion per-formance was determined for plywood.FTIR spectra showed the formation of urethane bonds and the reaction between lignin and silane.The NIPU adhesives prepared with C-HKL showed the highest adhesion strength among the three lignin-based NIPU adhesives.As the silane addition level increased,the adhesion strength of NIPU adhesives increased whereas formaldehyde emission decreased for all NIPU adhesives prepared.These results indicate that NIPU adhesives based on technical kraft lignin have a great potential as polyol for the synth-esis of bio-based NIPU adhesives for wood bonding.展开更多
Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive surfaces.The micropillar arrays are composed of the resin pillars ...Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive surfaces.The micropillar arrays are composed of the resin pillars for adhesion and the substrate with different elastic modulus for supporting.The stress singularity at the bi-material corner between the pillars and the substrate can induce the failure of the micropillar-substrate corner and further hinder the fabrication and application of micropillar arrays,yet the design for the stability of the micropillar array lacks systematical and quantitative guides.In this work,we develop a semi-analytical method to provide the full expressions for the stress distribution within the bi-material corner combining analytical derivations and numerical calculations.The predictions for the stress within the singularity field can be obtained based on the full expressions of the stress.The good agreement between the predictions and the FEM results demonstrates the high reliability of our method.By adopting the strain energy density factor approach,the stability of the pillar-substrate corner is assessed by predicting the failure at the corner.For the elastic mismatch between the pillar and substrate given in this paper,the stability can be improved by increasing the ratio of the shear modulus of the substrate to that of the micropillar.Our study provides accurate predictions for the stress distribution at the bi-material corner and can guide the optimization of material combinations of the pillars and the substrate for more stable bioinspired dry adhesives.展开更多
A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial acti...A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial activity.Mussel-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the hydrogels.GO,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the surface.The experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/mL.Antibacterial activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of pigskin.These results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment.展开更多
In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-h...In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-heal within 45 min at room temperature with an efficient lead ion-blocking rate of 99.3%.The PUA film can be coated on a metal electrode with slight efficiency improvement from 23.96%to 24.15%.The thermal stability at 65℃and the humidity stability at 55%relative humidity(RH)are superior to the devices encapsulated with polyisobutylene.The PUA film has strong adhesion to the flexible substrate and the initial efficiency of the flexible perovskite module(17.2%)encapsulated by PUA remains 92.6%within 1825 h.These results suggest that PUA encapsulation is universal for rigid and flexible PSCs with enhanced stability and low lead hazards.Moreover,it was found that flexible PSCs can be well attached to various substrates with PUA,providing a facile route for the A-PSCs in various scenarios without additional encapsulation and installation.展开更多
Indonesia is one of the largest coconut-producing countries in the world.The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity.However,the effect ...Indonesia is one of the largest coconut-producing countries in the world.The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity.However,the effect of adhesives on the quality of coconut shell charcoal briquettes made using screw extruder machine has not been widely studied.This study aims to determine the effect of adhesive type on the quality of coconut shell charcoal briquettes.The process of fabricating briquettes in this study included crushing,mixing,blending,pressing,and drying.In the mixing process,3 types of adhesives were used,namely tapioca flour(Briquette_1),cassava flour(Briquette_2),and modified cassava flour(Briquette_3)with a concentration of 5%of the weight of coconut shell charcoal powders.The quality of the resulting briquettes and commercial briquettes will be evaluated by moisture content,ash content,volatile matter,fixed carbon,calorific value,density,compressive,and drop test testing.The results of this research showed that the type of adhesive had a significant effect on the quality of the briquettes produced.Specimen Briquette_1 had better quality than commercial briquettes(Briquette_4)and other briquette specimens.The test results showed that Briquette_1 produced briquettes with better compressive strength and friability than the other specimens,at 6.95 N/mm^(2) and 4.44%,respectively.The moisture content,ash content,fixed carbon,and calorific value of Briquette_1 have met the requirements set by the Indonesian National Standard(SNI)number 01-6235-2000.Meanwhile,the volatile matter content and density of Briquette_1 are by the standards of Japan and the United States America(USA).展开更多
Using non-toxic,low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal(UG)resin adhesive is a hot research topic that could be of great interest for the wood industry.However,urea-glyoxal(U...Using non-toxic,low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal(UG)resin adhesive is a hot research topic that could be of great interest for the wood industry.However,urea-glyoxal(UG)resins prepared by just using glyoxal instead of formaldehyde usually yields a lower degree of polymerization.This results in a poorer bonding performance and water resistance of UG resins.A good solution is to pre-react urea to preform polyurea molecules presenting already a certain degree of polymerization,and then to condense these with glyoxal to obtain a novel UG resin.Therefore,in this present work,the urea was reacted with hexamethylene diamine to form a polyurea named HU,and then this was used to react it with different amounts of glyoxal to synthesize hexamethylenediamine-urea-glyoxal(HUG)polycondensation resins,and to use this for bonding plywood.The results show that the glyoxal can well react with HU polyuria via addition and schiff base reaction,and also the HUG resin exhibits excellent bonding strength and water resistance.The shear strength of the plywood bonded with this HUG at 160°C hot press temperature as high as 1.93 MPa,2.16 MPa and 1.61 MPa,respectively,which meets the requirement of the China national standard GB/T 9846-2015(≥0.7 MPa),and can be a good choice as a wood adhesive for industrial application.展开更多
Purpose: The study was to evaluate the efficacy of cyanoacrylate tissue adhesive (CTA) application in corneal perforations. Method: This was a prospective study on 20 patients of corneal perforations who received cyan...Purpose: The study was to evaluate the efficacy of cyanoacrylate tissue adhesive (CTA) application in corneal perforations. Method: This was a prospective study on 20 patients of corneal perforations who received cyanoacrylate tissue adhesive application as treatment between March 2021 and March 2022 at Preah Ang Duong Hospital. The primary outcome measure was success rate of CTA application, while the secondary outcome was to measure postoperative best-corrected visual acuity (BCVA) and ocular complications. Results: The mean age of patients was 44.15 ± 16.05 years old and 7 (35%) were female. Causes of perforation were microbial infection in 12 patients (60%), trauma in 5 patients (25%), and sterile melting in 3 patients (15%). The perforation of size smaller than 1.5 mm was in 8 patients (40%) while 12 patients (60%) had perforated size between 1.5 mm to 3 mm. The perforation was 60% (12 patients) central, 25% (5 patients) paracentral, and 15% (3 patients) peripherally. Out of 20 patients, 5 patients (25%) received CTA application more than 1 time. The mean glue retention was 57.60 ± 31.84 days. Success rate of glue application (defined as intact globe without surgical intervention regardless of number of CTA applications) was 85%. At the last visit, 7 patients (35%) had BCVA of 6/120 or better. Common complications were uveitis (45%), ocular hypertension (30%), cataract (25%) and neovascularization (20%). No serious complications were found. Conclusion: Cyanoacrylate tissue adhesive is an effective treatment option in sealing corneal perforations with no serious complications. .展开更多
Over the last decade,the oriented strand board(OSB)market presented meaningful growth.However,as a woodbased product,because of its anatomical structure and chemical composition,OSB can be damaged by biodeterioration ...Over the last decade,the oriented strand board(OSB)market presented meaningful growth.However,as a woodbased product,because of its anatomical structure and chemical composition,OSB can be damaged by biodeterioration agents.Given that,the biodeterioration of OSB panels must be investigated to improve its durability.In this way,this work analyses the biological resistance against termites(Cryptotermes brevis and Nasutitermes corniger)of heat-treated OSB panels made with Eucalyptus wood glued with vegetable-based polyurethane-an ecofriendly and sustainable adhesive derived from castor oil.Various panels were produced with different layers compositions(face:core:face of 25:50:25 and 30:40:30)in wood mass proportion and were submitted to postproduction heat treatment(at 175℃ and 200℃)replacing the use of chemical insecticides.The influence of the layers variation and heat treatment temperature were evaluated,and these results were compared with commercial panels(made from pinus wood with insecticide).The results showed that the heat treatment did not improve the resistance against termite attack.However,all the experimental panels presented a satisfactory performance that was compatible with the commercial panels produced with insecticide available in the Brazilian market.The combination of Eucalyptus wood and castor oil adhesive to produce OSB,in any variation of layer composition,demonstrated natural resistance against termite attack compatible with the commercial panels,even without using chemical additives to increase durability.展开更多
Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particle...Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particles of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative humidity.In this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin adhesive.The results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar qualities.Coarse particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable distinctions.Overall,the demethylated lignin adhesive extracted from L.leucocephala bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.展开更多
The combination of endoscopic ultrasound with endoscopic treatment of type 1 gastric variceal hemorrhage may improve the robustness and generalizability of the findings in future studies.Moreover,the esophageal varice...The combination of endoscopic ultrasound with endoscopic treatment of type 1 gastric variceal hemorrhage may improve the robustness and generalizability of the findings in future studies.Moreover,the esophageal varices should also be included in the evaluation of treatment efficacy in subsequent studies to reach a more convincing conclusion.展开更多
Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used gi...Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used ginger oil,a phytochemical with potential therapeutic properties,to prepare ginger oil patches.High-performance liquid chromatography(HPLC)was used to quantify the main active component of ginger oil,6-gingerol.Transdermal absorption experiments were conducted to optimize the various pressure-sensitive adhesives and permeation enhancers,including their type and concentration.Subsequently,the ginger oil patches were optimized and subjected to content determination and property evaluations.A PTSD mouse model was established using the foot-shock method.The therapeutic effect of ginger oil patches on PTSD was assessed through pathological sections,behavioral tests,and the evaluation of biomarkers such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),brain-derived neurotrophic factor(BDNF),and melatonin(MT).Results: The results demonstrated that ginger oil patches exerted therapeutic effects against PTSD by inhibiting inflammatory responses and modulating MT and BDNF levels.Pharmacokinetic experiments revealed that ginger oil patches maintained a stable blood drug concentration for at least one day,addressing the rapid metabolism drawback of 6-gingerol and enhancing its therapeutic efficacy.Conclusions: Ginger oil can be prepared as a transdermal drug patch that meets these requirements,and the bioavailability of the prepared patch is better than that of oral administration.It can improve PTSD with good patient compliance and ease of administration.Therefore,it is a promising therapeutic formulation for the treatment of PTSD.展开更多
Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high tempera...Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high temperatures. Pre- or post-crosslinking is another method used to manufacture a conventional vinyl-based homopolymers or copolymers system with improved water resistance. Vinyl neodecanoate (VeoVa), N-methylolacrylamide (NMA), Methacrylamide, methacrylic acid (MAA), and other self-crosslinking comonomers are typically inserted to produce highly water-resistant vinyl based homopolymers or copolymers. Additionally, organic crosslinkers like glyoxal, glutaraldehyde, citric acid, tartaric acid, and the like, as well as inorganic crosslinkers like acidic metal salts like aluminium chloride, aluminium nitrate, boric acid, and the like, can be used to prepare the highly water-resistant vinyl based homopolymers or copolymers. It is also possible to combine the self-crosslinking comonomers with the organic crosslinkers. Recently, a different hybrid chemistry has been developed that improves lap shear strength, has outstanding water resistance, good durability, and doesn’t require any additional crosslinker agents. Two distinct polymers were combined to develop hybrid polymers. They usually involve mixing an organic polymer with a polymer. There are many capping agents that are used for polyurethanes to produce acrylics that are capped with polyurethane and used as an oligomer in PVAc wood glue. Here, in this paper, we reviewed the different hybrid chemistry based on polyurethane chemistry for wood bonding applications.展开更多
This study investigates the enhancement of mechanical and thermal properties in epoxy resins modified with polydimethylsiloxane (PDMS) for advanced adhesive applications. The research focuses on evaluating the tensile...This study investigates the enhancement of mechanical and thermal properties in epoxy resins modified with polydimethylsiloxane (PDMS) for advanced adhesive applications. The research focuses on evaluating the tensile strength, thermal stability, and glass transition temperature (Tg) of PDMS-toughened epoxy resins. The primary objective of this study was to explore the use of polydimethylsiloxane (PDMS) as an impact modifier for epoxy resin. We successfully synthesized a grafting copolymer of diglycidyl ether bisphenol-A (DGEBA) and hydroxyl-terminated polydimethylsiloxane (HTPDMS) through the condensation of hydroxyl groups. Triethylene tetraamine (TETA) was employed as the curing agent to cross-link both DGEBA and the HTPDMS copolymer. The chemical structure of the DGEBA-HTPDMS grafting copolymer was confirmed using fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (NMR) spectroscopy. Tensile testing of the cured materials indicated that the elongation at break increased upon addition of PDMS. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) revealed improved thermal stability for the DGEBA system with the incorporation of HTPDMS. These findings suggest that the Si-O-Si segments within the PDMS contribute to the improved mechanical and thermal properties of the DGEBA-based resin.展开更多
文摘Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each.In group 1,each tooth was hemisected into two halves.One half was assigned to control subgroup 1,which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing.In group 2,the teeth were also hemisected into two halves.One half was assigned to control subgroup 2,which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer.Microtensile bond strength was immediately tested after specimen preparation.Results When the adhesive was applied three times before light curing,the bond strength of the experimental subgroup 1(n=33,57.49±11.61 MPa) was higher than that of the control subgroup 1(n=31,49.71±11.43 MPa,P<0.05).When using the technique of applying multiple layers of adhesive with light curing each successive layer,no difference of immediate bond strength was observed between the control subgroup 2 and the experimental subgroup 2(P>0.05).Conclusion Multiple coatings of one-step self-etching adhesive can increase the immediate bond strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.
文摘Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 groups. In group 1, each tooth was hemisected into 2 halves. One half was assigned to the control subgroup 1, which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instruc- tions; the other half was assigned to experimental subgroup 1, in which the adhesive was applied three times before light curing. In group 2, one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instructions; for the other half, three layers of adhesive were applied with each successive layer of light curing. Specimens were stored in 0.9% NaC1 containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis. Results When the adhesive was applied three times before light curing, the bond strength of the ex- perimental subgroup 1 was significantly higher than that of the control subgroup 1 （47.46__＋13.91 vs. 38.12＋11.21 MPa, P〈O.05）. When using the technique of applying multiple layers of adhesive with each successive layer of light curing, no difference was observed in bond strength between the control subgroup and the experimental subgroup （39.40＋8.87 vs. 40.87-＋9.33 MPa, P〉O.05）. Conclusion Multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.
文摘Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping.Traditional pulp capping agent,calcium hydroxide,may not prevent microleakage.Selfetching system is a newly developed adhesive system,which could provide less microleakage and would not break down or dissolve,preventing the oral fluids and bacteria from the pulp along the cavity wall.This may reduce such clinical problems as postoperative sensitivity,secondary caries and marginal discoloration.Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response,with negative bacterial staining.Inclusion of antibacterial components into self-etching system,such as 12-methacryloyloxydodecylpyridinium bromide(MDPB)may inhibit bacteria and provide better clinical effects.It is speculated that using the self-etching adhesive system containing the antibacterial agent,such as MDPB,to the dental pulp directly or indirectly,may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.
基金supported by the National Natural Science Foundation of China(22032006,52075522,52322506)West Light Foundation of The Chinese Academy of Sciences(xbzg-zdsys-202211)+2 种基金Major Science and Technology Project of Gansu Province(No.23ZDGA011)the Youth Innovation Promotion Association of The Chinese Academy of Sciences(Y2023114)Key Research Project of Shandong Provincial Natural Science Foundation(ZR2021ZD27).
文摘Nature evolves soft but structural architectures with typical wet/lubricous/adhesive behavior,as well as tunable interface functionalities,such as superhydrophilicity,superhydrophobic,superlubricity,high adhesion,etc.In order to simulate this,new chemistry modification methods,novel polymers materials and advanced manufacture techniques are developed for engineering diverse bioinspired wet/lubricous/adhesive soft matter systems.This review focuses on two typical interface functionalities of soft architectures in nature:wet lubrication and wet adhesion.Correspondingly,systematic summaries of recent progress for constructing bioinspired wet/lubricious/adhesive soft matter systems are proposed,including the surface grafting methods to construct hydrophilic wet lubrication surfaces,the bionic design of mechanically robust and structured soft matter lubrication materials,the novel preparation of high-performance biomimetic wet adhesion materials,and the advanced manufacture of 3D soft matter-based wet/lubricious devices.Subsequently,the current strategies relying on diverse regulation factors including surface hydration/roughness,surface intrinsic states,bulk mechanics,as well as multi-factors synergy,are introduced and discussed for achieving dynamic friction or adhesion control of bioinspired soft matter lubrication/adhesion systems.Finally,the existing problems,challenges and future development directions of bioinspired wet/lubricious/adhesive soft matter materials and devices are discussed.This review provides clear guidance for designing bioinspired soft matter-based lubrication,adhesion,or adhesion-lubrication switchable systems,and would act as a necessary research handbook in the field of surface/interface wettability engineering,bioengineering,medical devices,soft robotics,etc.
文摘Objective: In the Healthy Child Action Enhancement Program (2021-2025), it is proposed to ensure the safety and health of newborns and to promote high-quality development of health. Our department established risk assessment criteria for medical adhesives in neonates by applying the best evidence in the management program for the reduction of medical adhesive-associated skin injuries in neonates, in terms of the use and removal of adhesives. Methods: A systematic search and quality assessment of topics related to medical adhesive-related skin injury in neonates was conducted to summarize the best evidence and to conduct a quality review in the neonatal unit. Results: After 2 rounds of review, medical and nursing staff in the neonatal unit had a 98% compliance rate for the knowledge of neonatal medical adhesive-related skin injury and a satisfactory compliance rate for the other 9 indicators;after the application of the evidence, the incidence of neonatal medical adhesive-related skin injury was significantly lower than that before the application of the evidence, and the differences were statistically significant (P Conclusion: The application of the best evidence-based management program in neonatal medical adhesive-associated skin injury can reduce the incidence of neonatal medical adhesive-associated skin injury, reduce neonatal infections, and improve the integrity of the protective skin barrier in neonates.
基金financially supported by the Shenzhen Science and Technology Program (JCYJ20200109105805902,JCYJ20220818095805012)the National Natural Science Foundation of China (22208221,22178221,42377487)+2 种基金the Scientific and Technological Plan of Guangdong Province (2019B090905005,2019B090911004)the Natural Science Foundation of Guangdong Province (2021A1515110751)the Guangdong Basic and Applied Basic Research Foundation (2022A1515110477,2021B1515120004)。
文摘Sluggish storage kinetics is considered as the main bottleneck of cathode materials for fast-charging aqueous zinc-ion batteries(AZIBs).In this report,we propose a novel in-situ self-etching strategy to unlock the Palm tree-like vanadium oxide/carbon nanofiber membrane(P-VO/C)as a robust freestanding electrode.Comprehensive investigations including the finite element simulation,in-situ X-ray diffraction,and in-situ electrochemical impedance spectroscopy disclosed it an electrochemically induced phase transformation mechanism from VO to layered Zn_(x)V_(2)O_5·nH_(2)O,as well as superior storage kinetics with ultrahigh pseudocapacitive contribution.As demonstrated,such electrode can remain a specific capacity of 285 mA h g^(-1)after 100 cycles at 1 A g^(-1),144.4 mA h g^(-1)after 1500 cycles at 30 A g^(-1),and even 97 mA h g^(-1)after 3000 cycles at 60 A g^(-1),respectively.Unexpectedly,an impressive power density of 78.9 kW kg^(-1)at the super-high current density of 100 A g^(-1)also can be achieved.Such design concept of in-situ self-etching free-standing electrode can provide a brand-new insight into extending the pseudocapacitive storage limit,so as to promote the development of high-power energy storage devices including but not limited to AZIBs.
基金funded by National Research and Innovation Agency,Republic of Indonesia,Research Grant No.65/II.7/HK/2022,titled Pengembangan Produk Oriented Strand Board Unggul dari Kayu Ringan dan Cepat Tumbuh dalam Rangka Pengembangan Produk Biokomposit Prospektif。
文摘More than a century after its initial synthesis,urea-formaldehyde(UF)resins still have dominant applications as adhesives,paints,and coatings.However,formaldehyde in this industry produces formaldehyde emissions that are dangerous to health.Scientists have spent the last decade replacing formaldehyde and phenol with environmentally friendly substances such as glyoxal and tannin to create bio-based adhesives.This review covers recent advances in synthesizing glyoxal tannin-based resins,especially those made from sustainable raw material substitutes and changes made to synthetic processes to improve mechanical properties.The efficacy of using tannin-glyoxal adhesives in producing wood-based composites has been proven.The glyoxylate reaction forms cross-linked bridges between the aromatic sites of the tannin and glyoxal molecular structures.Glyoxal tannin adhesive with a greater percentage of glyoxal than tannin will produce an adhesive with better characteristics.The gel time reduces as the hardener concentration rises from 7.5%to 15%when glyoxal is used in adhesives.However,excessive amounts of glyoxal will result in a decrease in viscosity values.Glyoxal exhibits faster delivery degradation when it reaches a maximum temperature of approximately 130°C,although it initiates the curing process slightly slower at 110°C.Adding glyoxal to tannin-based adhesives can improve the mechanical properties of composite boards.The wet shear strength of the resulting plywood is increased by 105.4%with the addition of 5-weight percent tannin-based resin with glyoxal as a cross-linker in Soy Protein Adhesive.With glyoxal as a hardener,the panels produced showed good internal bond strengths(>0.35 MPa)and met the international standard specifications for interior-grade panels.
基金supported by the National Research Foundation(NRF)of Korea,and funded by the Korean Government(MSIT)(Grant No.RS-2023-00240043).
文摘Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol for the synthesis of non-isocyanate polyurethane(NIPU)adhesives to substitute current polyurethane(PU)adhesives that have been synthesized with toxic isocyanate and polyols.Crude hardwood kraft lignin(C-HKL)was extracted from black liquor from a pulp mill followed by acetone fractionation to obtain acetone soluble-HKL(AS-HKL).Then,C-HKL,AS-HKL,and softwood sodium lignosulfonate(LS)were used for the synthesis of technical lignin-based NIPU adhesives through carbonation and polyamination and silane as a cross-linker.Their adhesion per-formance was determined for plywood.FTIR spectra showed the formation of urethane bonds and the reaction between lignin and silane.The NIPU adhesives prepared with C-HKL showed the highest adhesion strength among the three lignin-based NIPU adhesives.As the silane addition level increased,the adhesion strength of NIPU adhesives increased whereas formaldehyde emission decreased for all NIPU adhesives prepared.These results indicate that NIPU adhesives based on technical kraft lignin have a great potential as polyol for the synth-esis of bio-based NIPU adhesives for wood bonding.
基金supported by the National Natural Science Foundation of China(Grant No.12272276)the Fundamental Research Funds for the Central Universities(Grant No.2042023kf0194)the Shenzhen Science and Technology Program(Grant No.JCYJ20220530140606013)。
文摘Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive surfaces.The micropillar arrays are composed of the resin pillars for adhesion and the substrate with different elastic modulus for supporting.The stress singularity at the bi-material corner between the pillars and the substrate can induce the failure of the micropillar-substrate corner and further hinder the fabrication and application of micropillar arrays,yet the design for the stability of the micropillar array lacks systematical and quantitative guides.In this work,we develop a semi-analytical method to provide the full expressions for the stress distribution within the bi-material corner combining analytical derivations and numerical calculations.The predictions for the stress within the singularity field can be obtained based on the full expressions of the stress.The good agreement between the predictions and the FEM results demonstrates the high reliability of our method.By adopting the strain energy density factor approach,the stability of the pillar-substrate corner is assessed by predicting the failure at the corner.For the elastic mismatch between the pillar and substrate given in this paper,the stability can be improved by increasing the ratio of the shear modulus of the substrate to that of the micropillar.Our study provides accurate predictions for the stress distribution at the bi-material corner and can guide the optimization of material combinations of the pillars and the substrate for more stable bioinspired dry adhesives.
基金Funded by the National Key Research and Development(R&D) Program of China(No.2018YFB1105702)。
文摘A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial activity.Mussel-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the hydrogels.GO,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the surface.The experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/mL.Antibacterial activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of pigskin.These results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment.
基金financially supported by the China National Key Research and Development Plan Project(2019YFE0107200)the National Natural Science Foundation of China(52072284)+1 种基金Joint Funds of Natural Science Foundation of Hubei Province(2023cFD087)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHD2020-001)
文摘In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-heal within 45 min at room temperature with an efficient lead ion-blocking rate of 99.3%.The PUA film can be coated on a metal electrode with slight efficiency improvement from 23.96%to 24.15%.The thermal stability at 65℃and the humidity stability at 55%relative humidity(RH)are superior to the devices encapsulated with polyisobutylene.The PUA film has strong adhesion to the flexible substrate and the initial efficiency of the flexible perovskite module(17.2%)encapsulated by PUA remains 92.6%within 1825 h.These results suggest that PUA encapsulation is universal for rigid and flexible PSCs with enhanced stability and low lead hazards.Moreover,it was found that flexible PSCs can be well attached to various substrates with PUA,providing a facile route for the A-PSCs in various scenarios without additional encapsulation and installation.
文摘Indonesia is one of the largest coconut-producing countries in the world.The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity.However,the effect of adhesives on the quality of coconut shell charcoal briquettes made using screw extruder machine has not been widely studied.This study aims to determine the effect of adhesive type on the quality of coconut shell charcoal briquettes.The process of fabricating briquettes in this study included crushing,mixing,blending,pressing,and drying.In the mixing process,3 types of adhesives were used,namely tapioca flour(Briquette_1),cassava flour(Briquette_2),and modified cassava flour(Briquette_3)with a concentration of 5%of the weight of coconut shell charcoal powders.The quality of the resulting briquettes and commercial briquettes will be evaluated by moisture content,ash content,volatile matter,fixed carbon,calorific value,density,compressive,and drop test testing.The results of this research showed that the type of adhesive had a significant effect on the quality of the briquettes produced.Specimen Briquette_1 had better quality than commercial briquettes(Briquette_4)and other briquette specimens.The test results showed that Briquette_1 produced briquettes with better compressive strength and friability than the other specimens,at 6.95 N/mm^(2) and 4.44%,respectively.The moisture content,ash content,fixed carbon,and calorific value of Briquette_1 have met the requirements set by the Indonesian National Standard(SNI)number 01-6235-2000.Meanwhile,the volatile matter content and density of Briquette_1 are by the standards of Japan and the United States America(USA).
基金supported by the Yunnan Provincial Natural Science Foundation (202201AU070222,202201AT070045,202101BD070001-074)Scientific Research Fund Project of Yunnan Provincial Department of Education (2022J0490)financed by the 111 Project (D21027).
文摘Using non-toxic,low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal(UG)resin adhesive is a hot research topic that could be of great interest for the wood industry.However,urea-glyoxal(UG)resins prepared by just using glyoxal instead of formaldehyde usually yields a lower degree of polymerization.This results in a poorer bonding performance and water resistance of UG resins.A good solution is to pre-react urea to preform polyurea molecules presenting already a certain degree of polymerization,and then to condense these with glyoxal to obtain a novel UG resin.Therefore,in this present work,the urea was reacted with hexamethylene diamine to form a polyurea named HU,and then this was used to react it with different amounts of glyoxal to synthesize hexamethylenediamine-urea-glyoxal(HUG)polycondensation resins,and to use this for bonding plywood.The results show that the glyoxal can well react with HU polyuria via addition and schiff base reaction,and also the HUG resin exhibits excellent bonding strength and water resistance.The shear strength of the plywood bonded with this HUG at 160°C hot press temperature as high as 1.93 MPa,2.16 MPa and 1.61 MPa,respectively,which meets the requirement of the China national standard GB/T 9846-2015(≥0.7 MPa),and can be a good choice as a wood adhesive for industrial application.
文摘Purpose: The study was to evaluate the efficacy of cyanoacrylate tissue adhesive (CTA) application in corneal perforations. Method: This was a prospective study on 20 patients of corneal perforations who received cyanoacrylate tissue adhesive application as treatment between March 2021 and March 2022 at Preah Ang Duong Hospital. The primary outcome measure was success rate of CTA application, while the secondary outcome was to measure postoperative best-corrected visual acuity (BCVA) and ocular complications. Results: The mean age of patients was 44.15 ± 16.05 years old and 7 (35%) were female. Causes of perforation were microbial infection in 12 patients (60%), trauma in 5 patients (25%), and sterile melting in 3 patients (15%). The perforation of size smaller than 1.5 mm was in 8 patients (40%) while 12 patients (60%) had perforated size between 1.5 mm to 3 mm. The perforation was 60% (12 patients) central, 25% (5 patients) paracentral, and 15% (3 patients) peripherally. Out of 20 patients, 5 patients (25%) received CTA application more than 1 time. The mean glue retention was 57.60 ± 31.84 days. Success rate of glue application (defined as intact globe without surgical intervention regardless of number of CTA applications) was 85%. At the last visit, 7 patients (35%) had BCVA of 6/120 or better. Common complications were uveitis (45%), ocular hypertension (30%), cataract (25%) and neovascularization (20%). No serious complications were found. Conclusion: Cyanoacrylate tissue adhesive is an effective treatment option in sealing corneal perforations with no serious complications. .
基金financed by Coordination for the Improvement of Higher Education Personnel,Brazil(CAPES,https://www.gov.br/capes/pt-br)(accessed on 22 September 2024)Finance Code 001(ESS,FDM)+1 种基金Sao Paulo State Research Support Foundation(FAPESP,https://fapesp.br/)(accessed on 22 September 2024)(CIC,grant number 2015/04660-0)National Council for Scientific and Technological Development(CNPq,https://www.gov.br/cnpq/pt-br)(accessed on 22 September 2024)(grant numbers 308937/2021-0(CIC),306576/2020-1(ECB),and 303099/2022-4(JBP)).
文摘Over the last decade,the oriented strand board(OSB)market presented meaningful growth.However,as a woodbased product,because of its anatomical structure and chemical composition,OSB can be damaged by biodeterioration agents.Given that,the biodeterioration of OSB panels must be investigated to improve its durability.In this way,this work analyses the biological resistance against termites(Cryptotermes brevis and Nasutitermes corniger)of heat-treated OSB panels made with Eucalyptus wood glued with vegetable-based polyurethane-an ecofriendly and sustainable adhesive derived from castor oil.Various panels were produced with different layers compositions(face:core:face of 25:50:25 and 30:40:30)in wood mass proportion and were submitted to postproduction heat treatment(at 175℃ and 200℃)replacing the use of chemical insecticides.The influence of the layers variation and heat treatment temperature were evaluated,and these results were compared with commercial panels(made from pinus wood with insecticide).The results showed that the heat treatment did not improve the resistance against termite attack.However,all the experimental panels presented a satisfactory performance that was compatible with the commercial panels produced with insecticide available in the Brazilian market.The combination of Eucalyptus wood and castor oil adhesive to produce OSB,in any variation of layer composition,demonstrated natural resistance against termite attack compatible with the commercial panels,even without using chemical additives to increase durability.
基金the financial support provided by UMS Great(GUG0217-1/2018),which played a crucial role in the completion of this study.
文摘Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particles of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative humidity.In this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin adhesive.The results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar qualities.Coarse particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable distinctions.Overall,the demethylated lignin adhesive extracted from L.leucocephala bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.
文摘The combination of endoscopic ultrasound with endoscopic treatment of type 1 gastric variceal hemorrhage may improve the robustness and generalizability of the findings in future studies.Moreover,the esophageal varices should also be included in the evaluation of treatment efficacy in subsequent studies to reach a more convincing conclusion.
基金supported by the National Natural Scientific Foundation(82172186)Beijing Natural Scientific Foundation(L222126).
文摘Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used ginger oil,a phytochemical with potential therapeutic properties,to prepare ginger oil patches.High-performance liquid chromatography(HPLC)was used to quantify the main active component of ginger oil,6-gingerol.Transdermal absorption experiments were conducted to optimize the various pressure-sensitive adhesives and permeation enhancers,including their type and concentration.Subsequently,the ginger oil patches were optimized and subjected to content determination and property evaluations.A PTSD mouse model was established using the foot-shock method.The therapeutic effect of ginger oil patches on PTSD was assessed through pathological sections,behavioral tests,and the evaluation of biomarkers such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),brain-derived neurotrophic factor(BDNF),and melatonin(MT).Results: The results demonstrated that ginger oil patches exerted therapeutic effects against PTSD by inhibiting inflammatory responses and modulating MT and BDNF levels.Pharmacokinetic experiments revealed that ginger oil patches maintained a stable blood drug concentration for at least one day,addressing the rapid metabolism drawback of 6-gingerol and enhancing its therapeutic efficacy.Conclusions: Ginger oil can be prepared as a transdermal drug patch that meets these requirements,and the bioavailability of the prepared patch is better than that of oral administration.It can improve PTSD with good patient compliance and ease of administration.Therefore,it is a promising therapeutic formulation for the treatment of PTSD.
文摘Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high temperatures. Pre- or post-crosslinking is another method used to manufacture a conventional vinyl-based homopolymers or copolymers system with improved water resistance. Vinyl neodecanoate (VeoVa), N-methylolacrylamide (NMA), Methacrylamide, methacrylic acid (MAA), and other self-crosslinking comonomers are typically inserted to produce highly water-resistant vinyl based homopolymers or copolymers. Additionally, organic crosslinkers like glyoxal, glutaraldehyde, citric acid, tartaric acid, and the like, as well as inorganic crosslinkers like acidic metal salts like aluminium chloride, aluminium nitrate, boric acid, and the like, can be used to prepare the highly water-resistant vinyl based homopolymers or copolymers. It is also possible to combine the self-crosslinking comonomers with the organic crosslinkers. Recently, a different hybrid chemistry has been developed that improves lap shear strength, has outstanding water resistance, good durability, and doesn’t require any additional crosslinker agents. Two distinct polymers were combined to develop hybrid polymers. They usually involve mixing an organic polymer with a polymer. There are many capping agents that are used for polyurethanes to produce acrylics that are capped with polyurethane and used as an oligomer in PVAc wood glue. Here, in this paper, we reviewed the different hybrid chemistry based on polyurethane chemistry for wood bonding applications.
文摘This study investigates the enhancement of mechanical and thermal properties in epoxy resins modified with polydimethylsiloxane (PDMS) for advanced adhesive applications. The research focuses on evaluating the tensile strength, thermal stability, and glass transition temperature (Tg) of PDMS-toughened epoxy resins. The primary objective of this study was to explore the use of polydimethylsiloxane (PDMS) as an impact modifier for epoxy resin. We successfully synthesized a grafting copolymer of diglycidyl ether bisphenol-A (DGEBA) and hydroxyl-terminated polydimethylsiloxane (HTPDMS) through the condensation of hydroxyl groups. Triethylene tetraamine (TETA) was employed as the curing agent to cross-link both DGEBA and the HTPDMS copolymer. The chemical structure of the DGEBA-HTPDMS grafting copolymer was confirmed using fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (NMR) spectroscopy. Tensile testing of the cured materials indicated that the elongation at break increased upon addition of PDMS. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) revealed improved thermal stability for the DGEBA system with the incorporation of HTPDMS. These findings suggest that the Si-O-Si segments within the PDMS contribute to the improved mechanical and thermal properties of the DGEBA-based resin.
