Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges re...Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges remain in their low site density and unsatisfactory mass transfer structure.Herein,we present a structural engineering approach employing a soft-template coating strategy to fabricate a hollow and hierarchically porous N-doped carbon framework anchored with atomically dispersed Fe sites(FeNCh) as an efficient ORR catalyst.The combination of hierarchical porosity and high exterior surface area is proven crucial for exposing more active sites,which gives rise to a remarkable ORR performance with a half-wave potential of 0.902 V in 0.1 m KOH and 0.814 V in 0.1 m HClO_(4),significantly outperforming its counterpart with solid structure and dominance of micropores(FeNC-s).The mass transfer property is revealed by in-situ electrochemical impedance spectroscopy(EIS) measurement.The distribution of relaxation time(DRT) analysis is further introduced to deconvolve the kinetic and mass transport processes,which demonstrates an alleviated mass transport resistance for FeNC-h,validating the effectiveness of structural engineering.This work not only provides an effective structural engineering approach but also contributes to the comprehensive mass transfer evaluation on advanced electrocatalyst for energy conversion applications.展开更多
Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concern...Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concerns impede its practical viability.This work provides a hydrogen-bonded organic framework(HOF)modification strategy to simultaneously improve the electrochemical performance,thermal stability and incombustibility of separator.Melamine cyanurate(MCA),as a low-cost and reliable flame-retardant HOF,was implemented in the separator modification layer,which can prevent the battery short circuit even at a high temperature.In addition,the supermolecule properties of MCA provide unique physical and chemical microenvironment for regulating ion-transport behavior in electrolyte.The MCA coating layer enabled the nickel-rich layered oxide cathode with a high-capacity retention of 90.3%after 300 cycles at 1.0 C.Collectively,the usage of MCA in lithium-ion batteries(LIBs)affords a simple,low-cost and efficient strategy to improve the security and service life of nickel-rich layered cathodes.展开更多
With the upgrading of industries,the cosmetics industry has posed new requirements for technical talents.As a professional core course in cosmetic technology,“Cosmetic Product Formulation Design and Preparation Techn...With the upgrading of industries,the cosmetics industry has posed new requirements for technical talents.As a professional core course in cosmetic technology,“Cosmetic Product Formulation Design and Preparation Technology”serves as the foundation for cultivating students’abilities in cosmetic development and preparation.To foster high-quality skilled talents capable of adapting to the rapid growth of color cosmetics and to better promote the deep integration of scientific and technological industries with curriculum teaching,the teacher team embarked on active explorations and practical teaching research for curriculum teaching reform from four dimensions:strengthening top-level design,enriching teaching content,optimizing teaching design,and reforming assessment methods.These efforts have enhanced students’comprehensive vocational qualities and innovative consciousness,contributing to the teaching reform in higher vocational colleges under the integration of industry,education,and research.展开更多
Active non-noble metal catalysts plays a decisive role for water electrolysis,however,the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging task.Herei...Active non-noble metal catalysts plays a decisive role for water electrolysis,however,the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging task.Herein,a facile one-step electrodeposition route in deep eutectic solvents(DESs) is developed for morphology-controllable synthesis of cobalt oxide/phosphate-carbon nano hybrids on nickel foam(CoPO@C/NF).A series of CoPO@C/NF nanostructures including cubes,octahedrons,microspheres and nanoflowers are synthesized,which show promising electrocatalytic properties toward oxygen and hydrogen evolution reactions(OER/HER).Such surface self-organized microstructure with accessible active sites make a significant contribution to the enhanced electrochemical activity,and hybridizing cobalt oxide with cobalt pyrophosphates and carbon can result in enhanced OER performance through synergistic catalysis.Among all nanostructures,the obtained microspherical CoPO@C/NF-3 catalyst exhibits excellent catalytic activities for OER and HER in 1.0 M KOH,affording an anodic current density of 10 mA cm^(-2) at overpotentials of 293 mV for OER and 93 mV for HER,with good long-time stability.This work offers a practical route for engineering the high-performance electrocatalysts towards efficient energy conversion and storage devices.展开更多
The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer(CRC).However,the effect of ginsenoside Rk3(Rk3)on CRC and gut microbiota remains unclear.Therefo...The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer(CRC).However,the effect of ginsenoside Rk3(Rk3)on CRC and gut microbiota remains unclear.Therefore,the purpose of this study is to explore the potential effect of Rk3 on CRC from the perspective of gut microbiota and immune regulation.Our results reveal that treatment with Rk3 significantly suppresses the formation of colon tumors,repairs intestinal barrier damage,and regulates the gut microbiota imbalance caused by CRC,including enrichment of probiotics such as Akkermansia muciniphila and Barnesiella intestinihominis,and clearance of pathogenic Desulfovibrio.Subsequent metabolomics data demonstrate that Rk3 can modulate the metabolism of amino acids and bile acids,particularly by upregulating glutamine,which has the potential to regulate the immune response.Furthermore,we elucidate the regulatory effects of Rk3 on chemokines and inflammatory factors associated with group 3 innate lymphoid cells(ILC3s)and T helper 17(Th17)signaling pathways,which inhibits the hyperactivation of the Janus kinase-signal transducer and activator of transcription 3(JAK-STAT3)signaling pathway.These results indicate that Rk3 modulates gut microbiota,regulates ILC3s immune response,and inhibits the JAK-STAT3 signaling pathway to suppress the development of colon tumors.More importantly,the results of fecal microbiota transplantation suggest that the inhibitory effect of Rk3 on colon tumors and its regulation of ILC3 immune responses are mediated by the gut microbiota.In summary,these findings emphasize that Rk3 can be utilized as a regulator of the gut microbiota for the prevention and treatment of CRC.展开更多
Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In...Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 kPa.The experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric heat.Both the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular sieve.Moreover,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) separation.The study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.展开更多
The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous me...The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction.展开更多
To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study invest...To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.展开更多
The centralized treatment method is a widely used form of wastewater treatment that tends to be less effective at removing toxic substances. Therefore, a detailed analysis of the composition of wastewater can provide ...The centralized treatment method is a widely used form of wastewater treatment that tends to be less effective at removing toxic substances. Therefore, a detailed analysis of the composition of wastewater can provide important information for the design of an effective wastewater treatment process. The objective of this paper was to investigate particle size distribution(PSD), biodegradability, and the chemical composition of the petrochemical wastewater discharges. For this purpose, this project selected the petrochemical wastewater and treated wastewater of China National Offshore Oil Corporation Zhongjie Petrochemical Co, Ltd. as the analysis objects.The step-by-step filtration method, along with a molecular weight classification method, was selected to build the chemical oxygen demand(COD) and biochemical oxygen demand(BOD) fingerprints of petrochemical wastewater and treated wastewater. The results showed that the main pollutants were settleable particles in petrochemical wastewater, which contributed to over 54.85% of the total COD. The colloidal particles with particle sizes in the range of 450–1000 nm had the highest COD value in the treated wastewater, which contributed34.17% of the total COD of treated wastewater. The results of the BOD analysis showed that the soluble fractions were the main reason that treated wastewaters did not meet the treatment standards. Tests on the organic compounds in petrochemical wastewater found that there were mainly linear paraffins, branched paraffins, benzene series compounds, and some plasticizers in the influent of the petrochemical wastewater. The most abundant pollutants in treated petrochemical wastewater were the adjacent diisobutyl phthalate and the linear alkanes.Fourier transform infrared(FTIR) transmission spectroscopy analysis showed that the settleable particles of petrochemical wastewater and membrane bioreactor(MBR)-treated wastewater contained multiple types of organic substances. The results also indicated that removing the oil-settleable substances, the colloidal particles(450–1000 nm), and the soluble organics will be necessary for the treatment of petrochemical wastewater.展开更多
The adsorption process of droplets on the liquid-liquid interface and phase separation process can regulate the spatial distribution of the fluid system,which are crucial for chemical engineering.However,the cross-lin...The adsorption process of droplets on the liquid-liquid interface and phase separation process can regulate the spatial distribution of the fluid system,which are crucial for chemical engineering.However,the cross-linking reaction,which is widely used in the field of polymers,can change the physical properties of the fluids and affect the flow behavior accordingly.A configuration of microchannels is designed to conveniently generate uniform droplets in one phase of the parallel flow.The flow behavior of the adsorption process of sodium alginate droplets on the liquid-liquid interface is investigated,and the subsequent process of phase separation is studied.In the process of droplet adsorption,the crosslinking reaction occurs synchronously,which makes the droplet viscosity and the elasticity modules of the droplet surface increase,thus affecting the dynamics of the adsorption process and the equilibrium shape of the droplet.The variation of the adsorption length with time is divided into three stages,which all conform to power law relationship.The exponents of the second and third stages deviate from the results of the Tanner's law.The flow pattern maps of droplet adsorption and phase separation are drawn,and the operating ranges of complete adsorption and complete separation are provided.This study provides a theoretical basis for further studying the flow behavior of droplets with cross-linking reaction in a microchannel.展开更多
The widespread use of pesticides has caused serious harm to ecosystems,necessitating effective and environmentally friendly treatment methods.Bioremediation stands out as a promising approach for pollutant treatment,w...The widespread use of pesticides has caused serious harm to ecosystems,necessitating effective and environmentally friendly treatment methods.Bioremediation stands out as a promising approach for pollutant treatment,wherein the metabolic activities of microorganisms can transform toxic pesticides into compounds with lower or no toxicity.In this study,we obtained eight pesticide-degrading strains from pesticide-contaminated sites through continuous enrichment and screening.Four highly efficient pesticide-degrading strains(degradation ratios exceeding 80%)were identified.Among them,Pseudomonas sp.BL5 exhibited the strongest growth(exceeding 10^(9) CFU·ml^(-1))and outstanding degradation of benzene derivatives and chlorinated hydrocarbons at both laboratory and pilot scales,with degradation ratios exceeding 98%and 99.6%,respectively.This research provides new tools and insights for the bioremediation of pesticide-related pollutants.展开更多
The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surf...The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surface analysis,and electrochemical measurements.Results demonstrated that the planktonic and sessile spore concentrations decline by more than two orders of magnitude when UV radiation and BKC are combinedly used compared with the control.UV radiation can inhibit the biological activity of A.terreus and influence the stability of passive film of AA7075.Except for direct disinfection,the physical adsorption of BKC on the specimen can effectively inhibit the attachment of A.terreus.The combination of UV radiation and BKC can much more effectively inhibit the corrosion of AA,especially pitting corrosion,due to their synergistic effect.The combined application of UV radiation and BKC can be a good method to effectively inhibit fungal-induced corrosion.展开更多
The quest for sustainable energy storage solutions is more critical than ever,with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources.Carbon nanotubes(CNTs),with thei...The quest for sustainable energy storage solutions is more critical than ever,with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources.Carbon nanotubes(CNTs),with their exceptional electrical conduct-ivity and structural integrity,are at the forefront of this endeavor,offering promising ways for the advance of electrochemical energy storage(EES)devices.This review provides an analysis of the synthesis,properties,and applications of CNTs in the context of EES.We explore the evolution of CNT synthesis methods,including arc discharge,laser ablation,and chemical vapor deposition,and highlight the recent developments in metal-organic framework-derived CNTs and a novel CNT aggregate with a three-dimensional ordered macroporous structure.We also examine the role of CNTs in improving the performance of various EES devices such as lith-ium-ion,lithium-metal,lithium-sulfur,sodium,and flexible batteries as well as supercapacitors.We underscore the challenges that remain,including the scalability of CNT synthesis and the integration of CNTs in electrode materials,and propose potential solu-tions and future research directions.The review presents a forward-looking perspective on the pivotal role of CNTs in shaping the fu-ture of sustainable EES technologies.展开更多
To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling s...To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.展开更多
The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal...The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.展开更多
Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin...Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.展开更多
Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells(DSSCs). Despite the common use of the donor-π bridge-acceptor architecture in designing sensitizers...Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells(DSSCs). Despite the common use of the donor-π bridge-acceptor architecture in designing sensitizers, the underlying structure-performance relationship remains not fully understood. In this study, we synthesized and characterized three sensitizers: MOTP-Pyc, MOS_(2)P-Pyc, and MOTS_(2)P-Pyc, all featuring a bipyrimidine acceptor. Absorption spectra, cyclic voltammetry, and transient photoluminescence spectra reveal a photo-induced electron transfer(PET) process in the excited sensitizers. Electron spin resonance spectroscopy confirmed the presence of charge-separated states. The varying donor and π-bridge structures among the three sensitizers led to differences in their conjugation effect, influencing light absorption abilities and PET processes and ultimately impacting the photovoltaic performance. Among the synthesized sensitizers, MOTP-Pyc demonstrated a DSSC efficiency of 3.04%. Introducing an additional thienothiophene block into the π-bridge improved the DSSC efficiency to 4.47% for MOTS_(2)P-Pyc. Conversely, replacing the phenyl group with a thienothiophene block reduced DSSC efficiency to 2.14% for MOS_(2)P-Pyc. Given the proton-accepting ability of the bipyrimidine module, we treated the dye-sensitized TiO_(2) photoanodes with hydroiodic acid(HI), significantly broadening the light absorption range. This treatment greatly enhanced the short-circuit current density of DSSCs owing to the enhanced electron-withdrawing ability of the acceptor. Consequently, the HI-treated MOTS_(2)P-Pyc-based DSSCs achieved the highest power conversion efficiency of 7.12%, comparable to that of the N719 dye at 7.09%. This work reveals the positive role of bipyrimidine in the design of organic sensitizers for DSSC applications.展开更多
Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport cha...Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild conditions.This LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to air.The reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of electrons.For a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.展开更多
Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell application.In this work,Pt catalysts supported on Ce...Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell application.In this work,Pt catalysts supported on CeO_(2)and Tb-doped CeO_(2)were prepared by a precipitation method.The physical structure and chemical properties of the as-prepared catalysts were characterized by powder X-ray diffraction,scanning electron microscopy,transmission electron microscopy,Raman spectroscopy,H_(2)temperature programmed reduction,and X-ray photoelectron spectroscopy.The results show that Tb-doped CeO_(2)supported Pt possesses abundant surface oxygen vacancies,good inhibition of ceria sintering,and strong metal-support interaction compared with CeO_(2)supported Pt.The catalytic performance of hydrogen production via steam reforming of long-chain hydrocarbon fuels(n-dodecane)was tested.Compared with 2Pt/CeO_(2),2Pt/Ce_(0.9)Tb_(0.1)O_(2),and 2Pt/Ce_(0.5)Tb_(0.5)O_(2),the 2Pt/Ce_(0.7)Tb_(0.3)O_(2)has higher activity and stability for hydrogen production,on which the conversion of n-dodecane was maintained at about 53.2%after 600 min reaction under 700℃at liquid space velocity of 9 ml·g^(-1)·h^(-1).2Pt/CeO_(2)rapidly deactivated,the conversion of n-dodecane was reduced to only 41.6%after 600 min.展开更多
The liquid hold-up in a reactive distillation(RD)column not only has a significant impact on the extent of reactions,but also affects the pressure drop and hydraulic conditions in the column.Therefore,the liquid hold-...The liquid hold-up in a reactive distillation(RD)column not only has a significant impact on the extent of reactions,but also affects the pressure drop and hydraulic conditions in the column.Therefore,the liquid hold-up would be a critical design factor for RD columns.However,the existing design methods for RD columns typically neglect the influence of considerable amount of liquid hold-up in downcomers owing to the difficulties of solving a large-scale nonlinear model system by considering downcomer hydraulics,resulting in significant deviations from actual situation and even operation infeasibility of the designed column.In this paper,a pseudo-transient(PT)RD model based on equilibrium model considering tray hydraulics was established for rigorous simulation and optimization of RD plate columns considering the liquid hold-up both in downcomers and column trays,and a steady-state optimization algorithm assisted by the PT model was adopted to robustly solve the optimization problem.The optimization results of either ethylene glycol RD or methyl acetate RD demonstrated that assuming all the liquid hold-up of a stage belonged to the tray will cause significant deviations in the column diameter,weir height,and the number of stages,which leads to not meeting the separation requirements and even operation hydraulic infeasibility.The rigorous model proposed in this study which considers the liquid hold-up both on trays and in downcomers as well as hydraulic constraints can be applied to systematically design industrial RD plate columns to simultaneously obtain optimal operating variables and equipment structure variables.展开更多
基金National Natural Science Foundation of China (Nos. 22078242 and U20A20153)Applied Basic Research Program of Yunnan Province (Nos. 202101BE070001-032 and 202101BH070002)。
文摘Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges remain in their low site density and unsatisfactory mass transfer structure.Herein,we present a structural engineering approach employing a soft-template coating strategy to fabricate a hollow and hierarchically porous N-doped carbon framework anchored with atomically dispersed Fe sites(FeNCh) as an efficient ORR catalyst.The combination of hierarchical porosity and high exterior surface area is proven crucial for exposing more active sites,which gives rise to a remarkable ORR performance with a half-wave potential of 0.902 V in 0.1 m KOH and 0.814 V in 0.1 m HClO_(4),significantly outperforming its counterpart with solid structure and dominance of micropores(FeNC-s).The mass transfer property is revealed by in-situ electrochemical impedance spectroscopy(EIS) measurement.The distribution of relaxation time(DRT) analysis is further introduced to deconvolve the kinetic and mass transport processes,which demonstrates an alleviated mass transport resistance for FeNC-h,validating the effectiveness of structural engineering.This work not only provides an effective structural engineering approach but also contributes to the comprehensive mass transfer evaluation on advanced electrocatalyst for energy conversion applications.
基金supported by the National Key Research and Development Program of China(No.2022YFA1504100)the National Natural Science Foundation of China(Nos.22005215,22279089,and 22178251).
文摘Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concerns impede its practical viability.This work provides a hydrogen-bonded organic framework(HOF)modification strategy to simultaneously improve the electrochemical performance,thermal stability and incombustibility of separator.Melamine cyanurate(MCA),as a low-cost and reliable flame-retardant HOF,was implemented in the separator modification layer,which can prevent the battery short circuit even at a high temperature.In addition,the supermolecule properties of MCA provide unique physical and chemical microenvironment for regulating ion-transport behavior in electrolyte.The MCA coating layer enabled the nickel-rich layered oxide cathode with a high-capacity retention of 90.3%after 300 cycles at 1.0 C.Collectively,the usage of MCA in lithium-ion batteries(LIBs)affords a simple,low-cost and efficient strategy to improve the security and service life of nickel-rich layered cathodes.
文摘With the upgrading of industries,the cosmetics industry has posed new requirements for technical talents.As a professional core course in cosmetic technology,“Cosmetic Product Formulation Design and Preparation Technology”serves as the foundation for cultivating students’abilities in cosmetic development and preparation.To foster high-quality skilled talents capable of adapting to the rapid growth of color cosmetics and to better promote the deep integration of scientific and technological industries with curriculum teaching,the teacher team embarked on active explorations and practical teaching research for curriculum teaching reform from four dimensions:strengthening top-level design,enriching teaching content,optimizing teaching design,and reforming assessment methods.These efforts have enhanced students’comprehensive vocational qualities and innovative consciousness,contributing to the teaching reform in higher vocational colleges under the integration of industry,education,and research.
基金supported by the National Natural Science Foundation of China (21421001, 21875118)the Natural Science Foundation of Xinjiang Autonomous Region (2016D01A009)+1 种基金the 111 project (B12015)the Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering (2020-KF-22)。
文摘Active non-noble metal catalysts plays a decisive role for water electrolysis,however,the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging task.Herein,a facile one-step electrodeposition route in deep eutectic solvents(DESs) is developed for morphology-controllable synthesis of cobalt oxide/phosphate-carbon nano hybrids on nickel foam(CoPO@C/NF).A series of CoPO@C/NF nanostructures including cubes,octahedrons,microspheres and nanoflowers are synthesized,which show promising electrocatalytic properties toward oxygen and hydrogen evolution reactions(OER/HER).Such surface self-organized microstructure with accessible active sites make a significant contribution to the enhanced electrochemical activity,and hybridizing cobalt oxide with cobalt pyrophosphates and carbon can result in enhanced OER performance through synergistic catalysis.Among all nanostructures,the obtained microspherical CoPO@C/NF-3 catalyst exhibits excellent catalytic activities for OER and HER in 1.0 M KOH,affording an anodic current density of 10 mA cm^(-2) at overpotentials of 293 mV for OER and 93 mV for HER,with good long-time stability.This work offers a practical route for engineering the high-performance electrocatalysts towards efficient energy conversion and storage devices.
基金supported by the National Key Research and Development Program,China(Grant Nos.:2021YFC2101500 and 2021YFC2103900)the National Natural Science Foundation of China(Grant Nos.:22278335 and 21978236)the Natural Science Basic Research Program of Shaanxi,China(Grant No.:2023-JC-JQ-17).
文摘The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer(CRC).However,the effect of ginsenoside Rk3(Rk3)on CRC and gut microbiota remains unclear.Therefore,the purpose of this study is to explore the potential effect of Rk3 on CRC from the perspective of gut microbiota and immune regulation.Our results reveal that treatment with Rk3 significantly suppresses the formation of colon tumors,repairs intestinal barrier damage,and regulates the gut microbiota imbalance caused by CRC,including enrichment of probiotics such as Akkermansia muciniphila and Barnesiella intestinihominis,and clearance of pathogenic Desulfovibrio.Subsequent metabolomics data demonstrate that Rk3 can modulate the metabolism of amino acids and bile acids,particularly by upregulating glutamine,which has the potential to regulate the immune response.Furthermore,we elucidate the regulatory effects of Rk3 on chemokines and inflammatory factors associated with group 3 innate lymphoid cells(ILC3s)and T helper 17(Th17)signaling pathways,which inhibits the hyperactivation of the Janus kinase-signal transducer and activator of transcription 3(JAK-STAT3)signaling pathway.These results indicate that Rk3 modulates gut microbiota,regulates ILC3s immune response,and inhibits the JAK-STAT3 signaling pathway to suppress the development of colon tumors.More importantly,the results of fecal microbiota transplantation suggest that the inhibitory effect of Rk3 on colon tumors and its regulation of ILC3 immune responses are mediated by the gut microbiota.In summary,these findings emphasize that Rk3 can be utilized as a regulator of the gut microbiota for the prevention and treatment of CRC.
基金supported by the renewable energy and hydrogen projects in National Key Research and Development Plan of China(2019YFB1505000).
文摘Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 kPa.The experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric heat.Both the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular sieve.Moreover,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) separation.The study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.
基金funded by the National Natural Science Foundation of China,China (Nos.52272303 and 52073212)the General Program of Municipal Natural Science Foundation of Tianjin,China (Nos.17JCYBJC22700 and 17JCYBJC17000)the State Scholarship Fund of China Scholarship Council,China (Nos.201709345012 and 201706255009)。
文摘The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction.
基金jointly supported by the National Key Research and Development Program of China (2019YFC1905800)the National Key Research & Development Program of China (2018YFC1903500)+4 种基金the commercial project by Beijing Zhong Dian Hua Yuan Environment Protection Technology Co., Ltd. (E01211200005)the Regional key projects of the science and technology service network program (STS program) of the Chinese Academy of Sciences (KFJ-STS-QYZD-153)the Ningbo Science and Technology Innovation Key Projects (2020Z099, 2022Z028)the Ningbo Municipal Commonweal Key Program (2019C10033)the support of Mineral Resources Analytical and Testing Center, Institute of Process Engineering, Chinese Academy of Science
文摘To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.
基金Supported by the National Basic Research Program of China(2014CB745100)the National Natural Science Foundation of China(21576197)the Tianjin Key Research&Development Program(16YFXTSF00460)
文摘The centralized treatment method is a widely used form of wastewater treatment that tends to be less effective at removing toxic substances. Therefore, a detailed analysis of the composition of wastewater can provide important information for the design of an effective wastewater treatment process. The objective of this paper was to investigate particle size distribution(PSD), biodegradability, and the chemical composition of the petrochemical wastewater discharges. For this purpose, this project selected the petrochemical wastewater and treated wastewater of China National Offshore Oil Corporation Zhongjie Petrochemical Co, Ltd. as the analysis objects.The step-by-step filtration method, along with a molecular weight classification method, was selected to build the chemical oxygen demand(COD) and biochemical oxygen demand(BOD) fingerprints of petrochemical wastewater and treated wastewater. The results showed that the main pollutants were settleable particles in petrochemical wastewater, which contributed to over 54.85% of the total COD. The colloidal particles with particle sizes in the range of 450–1000 nm had the highest COD value in the treated wastewater, which contributed34.17% of the total COD of treated wastewater. The results of the BOD analysis showed that the soluble fractions were the main reason that treated wastewaters did not meet the treatment standards. Tests on the organic compounds in petrochemical wastewater found that there were mainly linear paraffins, branched paraffins, benzene series compounds, and some plasticizers in the influent of the petrochemical wastewater. The most abundant pollutants in treated petrochemical wastewater were the adjacent diisobutyl phthalate and the linear alkanes.Fourier transform infrared(FTIR) transmission spectroscopy analysis showed that the settleable particles of petrochemical wastewater and membrane bioreactor(MBR)-treated wastewater contained multiple types of organic substances. The results also indicated that removing the oil-settleable substances, the colloidal particles(450–1000 nm), and the soluble organics will be necessary for the treatment of petrochemical wastewater.
基金supported by the National Natural Science Foundation of China(92034303,21978197)。
文摘The adsorption process of droplets on the liquid-liquid interface and phase separation process can regulate the spatial distribution of the fluid system,which are crucial for chemical engineering.However,the cross-linking reaction,which is widely used in the field of polymers,can change the physical properties of the fluids and affect the flow behavior accordingly.A configuration of microchannels is designed to conveniently generate uniform droplets in one phase of the parallel flow.The flow behavior of the adsorption process of sodium alginate droplets on the liquid-liquid interface is investigated,and the subsequent process of phase separation is studied.In the process of droplet adsorption,the crosslinking reaction occurs synchronously,which makes the droplet viscosity and the elasticity modules of the droplet surface increase,thus affecting the dynamics of the adsorption process and the equilibrium shape of the droplet.The variation of the adsorption length with time is divided into three stages,which all conform to power law relationship.The exponents of the second and third stages deviate from the results of the Tanner's law.The flow pattern maps of droplet adsorption and phase separation are drawn,and the operating ranges of complete adsorption and complete separation are provided.This study provides a theoretical basis for further studying the flow behavior of droplets with cross-linking reaction in a microchannel.
基金supported by the National Key Research and Development Program of China(2018YFA0902100)the National Natural Science Foundation of China(22178262)the Tianjin Key Research and Development Program(23YFZCSN00110).
文摘The widespread use of pesticides has caused serious harm to ecosystems,necessitating effective and environmentally friendly treatment methods.Bioremediation stands out as a promising approach for pollutant treatment,wherein the metabolic activities of microorganisms can transform toxic pesticides into compounds with lower or no toxicity.In this study,we obtained eight pesticide-degrading strains from pesticide-contaminated sites through continuous enrichment and screening.Four highly efficient pesticide-degrading strains(degradation ratios exceeding 80%)were identified.Among them,Pseudomonas sp.BL5 exhibited the strongest growth(exceeding 10^(9) CFU·ml^(-1))and outstanding degradation of benzene derivatives and chlorinated hydrocarbons at both laboratory and pilot scales,with degradation ratios exceeding 98%and 99.6%,respectively.This research provides new tools and insights for the bioremediation of pesticide-related pollutants.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,China(No.2023A1515012146)the National Natural Science Foundation of China(No.52271083)+1 种基金the Fundamental Research Funds for the Central Universities,China(No.22qntd0801)the Shanghai Engineering Technology Research Centre of Deep Offshore Material,China(No.19DZ2253100)。
文摘The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surface analysis,and electrochemical measurements.Results demonstrated that the planktonic and sessile spore concentrations decline by more than two orders of magnitude when UV radiation and BKC are combinedly used compared with the control.UV radiation can inhibit the biological activity of A.terreus and influence the stability of passive film of AA7075.Except for direct disinfection,the physical adsorption of BKC on the specimen can effectively inhibit the attachment of A.terreus.The combination of UV radiation and BKC can much more effectively inhibit the corrosion of AA,especially pitting corrosion,due to their synergistic effect.The combined application of UV radiation and BKC can be a good method to effectively inhibit fungal-induced corrosion.
文摘The quest for sustainable energy storage solutions is more critical than ever,with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources.Carbon nanotubes(CNTs),with their exceptional electrical conduct-ivity and structural integrity,are at the forefront of this endeavor,offering promising ways for the advance of electrochemical energy storage(EES)devices.This review provides an analysis of the synthesis,properties,and applications of CNTs in the context of EES.We explore the evolution of CNT synthesis methods,including arc discharge,laser ablation,and chemical vapor deposition,and highlight the recent developments in metal-organic framework-derived CNTs and a novel CNT aggregate with a three-dimensional ordered macroporous structure.We also examine the role of CNTs in improving the performance of various EES devices such as lith-ium-ion,lithium-metal,lithium-sulfur,sodium,and flexible batteries as well as supercapacitors.We underscore the challenges that remain,including the scalability of CNT synthesis and the integration of CNTs in electrode materials,and propose potential solu-tions and future research directions.The review presents a forward-looking perspective on the pivotal role of CNTs in shaping the fu-ture of sustainable EES technologies.
基金National Natural Science Foundation of China(Grant Nos:22038011,51976168)K.C.Wong Education Foundation,the Natural Science Basic Research Program of Shaanxi(Program No.2021JLM-17)+1 种基金Programme of Introducing Talents of Discipline to Universities(B23025)Innovation Capability Support Program of Shaanxi(Program Nos:2023KJXX-004,2023-CX-TD-26,2022KXJ-126).
文摘To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.
基金supported by National Natural Science Foundation of China(21978066)Basic Research Program of Hebei Province for Natural Science Foundation and Key Basic Research Project(18964308D)the Key Program of Natural Science Foundation of Hebei Province(B2020202048).
文摘The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.
基金the support from National Key Research and Development Program of China(2021YFC2104400)the Tianjin Science and Technology Plan Project(21JCQNJC00340)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.
基金supported by the National Natural Science Foundation of China(Nos.21776207 and 21576195)。
文摘Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells(DSSCs). Despite the common use of the donor-π bridge-acceptor architecture in designing sensitizers, the underlying structure-performance relationship remains not fully understood. In this study, we synthesized and characterized three sensitizers: MOTP-Pyc, MOS_(2)P-Pyc, and MOTS_(2)P-Pyc, all featuring a bipyrimidine acceptor. Absorption spectra, cyclic voltammetry, and transient photoluminescence spectra reveal a photo-induced electron transfer(PET) process in the excited sensitizers. Electron spin resonance spectroscopy confirmed the presence of charge-separated states. The varying donor and π-bridge structures among the three sensitizers led to differences in their conjugation effect, influencing light absorption abilities and PET processes and ultimately impacting the photovoltaic performance. Among the synthesized sensitizers, MOTP-Pyc demonstrated a DSSC efficiency of 3.04%. Introducing an additional thienothiophene block into the π-bridge improved the DSSC efficiency to 4.47% for MOTS_(2)P-Pyc. Conversely, replacing the phenyl group with a thienothiophene block reduced DSSC efficiency to 2.14% for MOS_(2)P-Pyc. Given the proton-accepting ability of the bipyrimidine module, we treated the dye-sensitized TiO_(2) photoanodes with hydroiodic acid(HI), significantly broadening the light absorption range. This treatment greatly enhanced the short-circuit current density of DSSCs owing to the enhanced electron-withdrawing ability of the acceptor. Consequently, the HI-treated MOTS_(2)P-Pyc-based DSSCs achieved the highest power conversion efficiency of 7.12%, comparable to that of the N719 dye at 7.09%. This work reveals the positive role of bipyrimidine in the design of organic sensitizers for DSSC applications.
基金supported by the National Key R&D Program of China(2022YFA2105900)the National Natural Science Foundation of China(22178197)。
文摘Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild conditions.This LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to air.The reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of electrons.For a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.
基金supported by the Key Research and Design Program of Qinhuangdao(202101A005)the Science and Technology Project of Hebei Education Department(QN2023094)+2 种基金the Cultivation Project for Basic Research and Innovation of Yanshan University(2021LGQN028)the Project for Research and Development of Metal Catalysts for Photo-thermal Decomposition of Waste Plastics to Prepare Value-added Chemicals(x2023322)the Subsidy for Hebei Key Laboratory of Applied Chemistry after Operation Performance(22567616H).
文摘Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell application.In this work,Pt catalysts supported on CeO_(2)and Tb-doped CeO_(2)were prepared by a precipitation method.The physical structure and chemical properties of the as-prepared catalysts were characterized by powder X-ray diffraction,scanning electron microscopy,transmission electron microscopy,Raman spectroscopy,H_(2)temperature programmed reduction,and X-ray photoelectron spectroscopy.The results show that Tb-doped CeO_(2)supported Pt possesses abundant surface oxygen vacancies,good inhibition of ceria sintering,and strong metal-support interaction compared with CeO_(2)supported Pt.The catalytic performance of hydrogen production via steam reforming of long-chain hydrocarbon fuels(n-dodecane)was tested.Compared with 2Pt/CeO_(2),2Pt/Ce_(0.9)Tb_(0.1)O_(2),and 2Pt/Ce_(0.5)Tb_(0.5)O_(2),the 2Pt/Ce_(0.7)Tb_(0.3)O_(2)has higher activity and stability for hydrogen production,on which the conversion of n-dodecane was maintained at about 53.2%after 600 min reaction under 700℃at liquid space velocity of 9 ml·g^(-1)·h^(-1).2Pt/CeO_(2)rapidly deactivated,the conversion of n-dodecane was reduced to only 41.6%after 600 min.
基金supported by the National Natural Science Foundation of China(22378304).
文摘The liquid hold-up in a reactive distillation(RD)column not only has a significant impact on the extent of reactions,but also affects the pressure drop and hydraulic conditions in the column.Therefore,the liquid hold-up would be a critical design factor for RD columns.However,the existing design methods for RD columns typically neglect the influence of considerable amount of liquid hold-up in downcomers owing to the difficulties of solving a large-scale nonlinear model system by considering downcomer hydraulics,resulting in significant deviations from actual situation and even operation infeasibility of the designed column.In this paper,a pseudo-transient(PT)RD model based on equilibrium model considering tray hydraulics was established for rigorous simulation and optimization of RD plate columns considering the liquid hold-up both in downcomers and column trays,and a steady-state optimization algorithm assisted by the PT model was adopted to robustly solve the optimization problem.The optimization results of either ethylene glycol RD or methyl acetate RD demonstrated that assuming all the liquid hold-up of a stage belonged to the tray will cause significant deviations in the column diameter,weir height,and the number of stages,which leads to not meeting the separation requirements and even operation hydraulic infeasibility.The rigorous model proposed in this study which considers the liquid hold-up both on trays and in downcomers as well as hydraulic constraints can be applied to systematically design industrial RD plate columns to simultaneously obtain optimal operating variables and equipment structure variables.
