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不良修复体引起的组织变化 被引量:1
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作者 徐建芳 朱和相 陈菱 《口腔医学》 CAS 北大核心 1999年第4期205-206,共2页
人体正常的牙列不仅有利于美观而且对咀嚼功能的发挥及口颌系统的完整性是至关重要的临床上常见因外伤、龋病、牙周病等引起的牙列缺损或牙列缺失病人一副设计合理戴用舒适且符合口腔生物学要求的修复体不仅可以恢复缺损及缺失的口腔软... 人体正常的牙列不仅有利于美观而且对咀嚼功能的发挥及口颌系统的完整性是至关重要的临床上常见因外伤、龋病、牙周病等引起的牙列缺损或牙列缺失病人一副设计合理戴用舒适且符合口腔生物学要求的修复体不仅可以恢复缺损及缺失的口腔软、硬组织而且能保护剩余口腔软、硬组... 展开更多
关键词 牙列 移复体 副作用 组织变化
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A New Method for InGaAs/InP Composite Channel HEMTs Simulation
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作者 刘亮 张海英 +4 位作者 尹军舰 李潇 徐静波 宋雨竹 刘训春 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1706-1711,共6页
A new method is used to simulate InGaAs/InP composite channel high electron mobility transistors (HEMTs). By coupling the hydrodynamic model and the density gradient model, the electron density distribution in the c... A new method is used to simulate InGaAs/InP composite channel high electron mobility transistors (HEMTs). By coupling the hydrodynamic model and the density gradient model, the electron density distribution in the channel in different electric fields is obtained. This method is faster and more robust than traditional meth- ods and should be applicable to other types of HEMTs simulations. A detailed study of the InGaAs/InP composite channel HEMTs is presented with the help of simulations. 展开更多
关键词 InP INGAAS composite channel HEMTS SIMULATION
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Photoinduced Electron Transfer Between Mono-6-p-nitrobenzoyl-β- cyclodextrin and Adamantanamine-Cn-Co/Ni-porphyrins
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作者 Guo-tao Wen Man-zhou Zhu +3 位作者 Hui-yuan Hu Xiang-ming Meng Zhuo Wang Qing-xiang Guo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第4期329-334,共6页
Two series monot ailed porphyrins, Cobalt-5- {4- [ω- (1-adamant aneamino) alkyloxy] phenyl }- 10,15,20-triphenyl porphyrinate (CoPCnA, n=4,5,6) and Nickel-5-{4-[ω-(1-adamantaneamino)alkyloxy]phenyl}-10,15.20- ... Two series monot ailed porphyrins, Cobalt-5- {4- [ω- (1-adamant aneamino) alkyloxy] phenyl }- 10,15,20-triphenyl porphyrinate (CoPCnA, n=4,5,6) and Nickel-5-{4-[ω-(1-adamantaneamino)alkyloxy]phenyl}-10,15.20- triphenyl porphyrinate (NiPCnA, n=4,5,6), were synthesized, in which the porphyrin moiety was connected to l-adamantanamine via a flexible hydrocarbon chain. The fluorescence quenching between these donor substrates and mono-6-p-nitrobenzoyl-β-cyclodextrin (NBCD) was studied in detail. Distinct fluorescence quenching occured in these supramolecular systems. This quenching was attributed to the photoinduced electron transfer (PET) inside the supramolecular assembly between the porphyrin donors and cyclodextrin acceptors. Detailed Stern-Volmer constants were measured and they were partitioned into dynamic Stern- Volmer quenching constants and static binding constants. It was demonstrated that the PET interaction between the porphyrin subunits and NBCD is indeed effective. 展开更多
关键词 Photoinduced electron transfer Host-guest complex CYCLODEXTRIN Supramolecular system Fluorescence quenching
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Investigation on the threshold control of safety blasting vibration velocity for the extraction of complicated orebody under railway 被引量:6
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作者 Jiang Lichunt Hu Liuqing Lai Xiuying 《Mining Science and Technology》 EI CAS 2011年第2期169-174,共6页
The threshold control of safety blasting vibration velocity is a significant process for the underground mining of complicated ore deposit under construction,road,and water.According to the equivalent principle of dis... The threshold control of safety blasting vibration velocity is a significant process for the underground mining of complicated ore deposit under construction,road,and water.According to the equivalent principle of displacement and velocity of mass point,differential evolution is put forward based on 3DEC dynamic analysis,making the calculation more efficient and accurate.The 3DEC model of the complicated orebody under railway is established according to the topographic maps and geological data of the eastern Pyrite Mine.The stimulus-response distribution of internal stress and displacement fields are demonstrated by analyzing the on-site monitoring vibration displacement and velocity data of the mass point.The reliability of parameter selection,such as blasting simulation waveforms,rock damping,is identified.The safety vibration velocity of railway is set to 4.5 cm/s in line with the requirement of safety blasting rules.Thus,the maximum amount of single-stage explosive in this region is 44.978 kg.The simulation result is in good agreement with the on-site monitoring datum.No displacement and settlement of the 701 railway special line was achieved by choosing the critical amount of the single-stage explosive. 展开更多
关键词 Mining under construction Road and water Blasting vibration The method of differential evolution Safety velocity Amount of single-stage explosive
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A Mass Transfer Model Based on Individual Bubbles and an Unsteady State Film Mechanism 被引量:1
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作者 赵斌 王铁峰 王金福 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期163-168,共6页
A gas-liquid mass transfer model based on an unsteady state film mechanism applied to a single bubble is presented. The mathematical model was solved using Laplace transform to obtain an analytical solution of concent... A gas-liquid mass transfer model based on an unsteady state film mechanism applied to a single bubble is presented. The mathematical model was solved using Laplace transform to obtain an analytical solution of concentration profile in terms of the radial position r and time t. The dynamic mass transfer flux was deduced and the influence of the bubble size was also determined. A mathematical method for deducing the average mass transfer flux directly from the Laplace transformed concentration is presented. Its accuracy is verified by comparing the numerical results with those from the indirect method. The influences of the model parameters, namely, the bubble size R, liquid film thickness δ, and the surface renewal constant s on the average mass transfer flux were investigated. The proposed model is useful for a better understanding of the mass transfer mechanism and an optimum design of gas-liquid contact equipment. 展开更多
关键词 film theory Laplace transformation mass diffusion penetration theory surface renewal theory
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Solvent Effects on Excited-State Relaxation Dynamics of Paddle-Wheel BODIPY-Hexaoxatriphenylene Conjugates:Insights from Non-adiabatic Dynamics Simulations
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作者 Wen-Kai Chen Ganglong Cui Xiang-Yang Liu 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期117-128,I0015-I0034,I0063,共33页
Understanding the excited state dynamics of donor-acceptor(D-A)complexes is of fundamental importance both experimentally and theoretically.Herein,we have first explored the photoinduced dynamics of a recently synthes... Understanding the excited state dynamics of donor-acceptor(D-A)complexes is of fundamental importance both experimentally and theoretically.Herein,we have first explored the photoinduced dynamics of a recently synthesized paddle-wheel BODIPY-hexaoxatriphenylene(BODIPY is the abbreviation for BF_(2)-chelated dipyrromethenes)conjugates D-A complexes with the combination of both electronic structure calculations and nonadiabatic dynamics simulations.On the basis of computational results,we concluded that the BODIPY-hexaoxatriphenylene(BH)conjugates will be promoted to the local excited(LE)states of the BODIPY fragments upon excitation,which is followed by the ultrafast exciton transfer from LE state to charge transfer(CT).Instead of the photoinduced electron transfer process proposed in previous experimental work,such a exciton transfer process is accompanied with the photoinduced hole transfer from BODIPY to hexaoxatriphenylene.Additionally,solvent effects are found to play an important role in the photoinduced dynamics.Specifically,the hole transfer dynamics is accelerated by the acetonitrile solvent,which can be ascribed to significant influences of the solvents on the charge transfer states,i.e.the energy gaps between LE and CT excitons are reduced greatly and the non-adiabatic couplings are increased in the meantime.Our present work not only provides valuable insights into the underlying photoinduced mechanism of BH,but also can be helpful for the future design of novel donor-acceptor conjugates with better optoelectronic performance. 展开更多
关键词 Donor-Acceptor conjugate BF_(2)-chelated dipyrromethene Solvent effect Non-adiabatic dynmamics EXCITED-STATE
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Synthesis of TiO_2/g-C_3N_4 nanocomposites with phosphate–oxygen functional bridges for improved photocatalytic activity 被引量:7
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作者 Chong Liu Fazal Raziq +3 位作者 Zhijun Li Yang Qu Amir Zada Liqiang Jing 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第6期1072-1078,共7页
One of the most general methods to enhance the separation of photogenerated carriers for g‐C3N4is to construct a suitable heterojunctional composite,according to the principle of matching energy levels.The interface ... One of the most general methods to enhance the separation of photogenerated carriers for g‐C3N4is to construct a suitable heterojunctional composite,according to the principle of matching energy levels.The interface contact in the fabricated nanocomposite greatly influences the charge transfer and separation so as to determine the final photocatalytic activities.However,the role of interface contact is often neglected,and is rarely reported to date.Hence,it is possible to further enhance the photocatalytic activity of g‐C3N4‐based nanocomposite by improving the interfacial connection.Herein,phosphate-oxygen(P-O)bridged TiO2/g‐C3N4nanocomposites were successfully synthesized using a simple wet chemical method,and the effects of the P-O functional bridges on the photogenerated charge separation and photocatalytic activity for pollutant degradation and CO2reduction were investigated.The photocatalytic activity of g‐C3N4was greatly improved upon coupling with an appropriate amount of nanocrystalline TiO2,especially with P-O bridged TiO2.Atmosphere‐controlled steady‐state surface photovoltage spectroscopy and photoluminescence spectroscopy analyses revealed clearly the enhancement of photogenerated charge separation of g‐C3N4upon coupling with the P-O bridged TiO2,resulting from the built P-O bridges between TiO2and g‐C3N4so as to promote effective transfer of excited electrons from g‐C3N4to TiO2.This enhancement was responsible for the improved photoactivity of the P-O bridged TiO2/g‐C3N4nanocomposite,which exhibited three‐time photocatalytic activity enhancement for2,4‐dichlorophenol degradation and CO2reduction compared with bare g‐C3N4.Furthermore,radical‐trapping experiments revealed that the·OH species formed as hole‐modulated direct intermediates dominated the photocatalytic degradation of2,4‐dichlorophenol.This work provides a feasible strategy for the design and synthesis of high‐performance g‐C3N4‐based nanocomposite photocatalysts for pollutant degradation and CO2reduction. 展开更多
关键词 TiO2/graphitic carbon nitride NANOCOMPOSITE Phosphate–oxygen bridge Charge transfer and separation PHOTOCATALYSIS Carbon dioxide conversion
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Autograft-prosthesis composite for aggressive giant cell tumor of bone around knee
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作者 Xiuchun Yu Ming Xu Zhihou Fu Songfeng Xu 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第11期619-622,共4页
Objective: The aim of the research was to study the clinical feasibility of autograft-prosthesis composite for aggressive giant call tumor of bone around knee. Methods: Seven patients (5 males and 2 females, the me... Objective: The aim of the research was to study the clinical feasibility of autograft-prosthesis composite for aggressive giant call tumor of bone around knee. Methods: Seven patients (5 males and 2 females, the mean age of 30.5 years old) with giant cell tumor of bone around knee underwent tumor resection and reconstructed with autograft-prosthesis composites since January 2006. Five lesions located at the distal femur and 2 at the proximal tibia. There were 3 patients with primary tumor and 4 with recurrent. Three patients with pathological fracture and all patients were of Campanacci Ⅲ. Results: All patients were done follow-up from 12 to 36 months. No recurrence, metastasis, and prosthesis loosening were found. The mean healing time between autograft and host bone was 5 months. The mean motion range of affected knee were 90° (70°-110°). Conclusion: Our data documented the clinical feasibility of autograft-prosthesis composite for giant cell tumor of bone around knee which should be performed tumor resection and reconstructed with prosthesis. The long-term outcomes remain to be further proven. 展开更多
关键词 aggressive giant cell tumor of bone autograft-prosthesis composite KNEE
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An analytical biomarker for treatment of patients with recurrent B-ALL after remission induced by infusion of anti-CD19 chimeric antigen receptor T(CAR-T) cells 被引量:6
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作者 Yajing Zhang Wenying Zhang +12 位作者 Hanren Dai Yao Wang Fengxia Shi Chunmeng Wang Yelei Guo Yang Liu Meixia Chen Kaichao Feng Yan Zhang Chuanjie Liu Qingming Yang Suxia Li Weidong Han 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第4期379-385,共7页
Anti-CD19 chimeric antigen receptor-modified T(CAR-T-19) cells have emerged as a powerful targeted immunotherapy for B-cell lineage acute lymphoblastic leukemia with a remarkable clinical response in recent trials. No... Anti-CD19 chimeric antigen receptor-modified T(CAR-T-19) cells have emerged as a powerful targeted immunotherapy for B-cell lineage acute lymphoblastic leukemia with a remarkable clinical response in recent trials. Nonetheless, few data are available on the subsequent clinical monitoring and treatment of the patients, especially those with disease recurrence after CAR-T-19 cell infusion. Here, we analyzed three patients who survived after our phase I clinical trial and who were studied by means of biomarkers reflecting persistence of CAR-T-19 cells in vivo and predictive factors directing further treatment. One patient achieved 9-week sustained complete remission and subsequently received an allogeneic hematopoietic stem cell transplant. Another patient who showed relapse after 20 weeks without detectable leukemia in the cerebrospinal fluid after CAR-T-19 cell treatment was able to achieve a morphological remission under the influence of stand-alone low-dose chemotherapeutic agents. The third patient gradually developed extensive extramedullary involvement in tissues with scarce immune-cell infiltration during a long period of hematopoietic remission after CAR-T-19 cell therapy. Long-term and discontinuous increases in serum cytokines(mainly interleukin 6 and C-reactive protein) were identified in two patients(Nos. 1 and 6) even though only a low copy number of CAR molecules could be detected in their peripheral blood. This finding was suggestive of persistent functional activity of CAR-T-19 cells. Combined analyses of laboratory biomarkers with their clinical manifestations before and after salvage treatment showed that the persistent immunosurveillance mediated by CAR-T-19 cells would inevitably potentiate the leukemia-killing effectiveness of subsequent chemotherapy in patients who showed relapse after CAR-T-19-induced remission. 展开更多
关键词 chimeric antigen receptor T cells B-cell acute lymphoblastic leukemia biomarker immunosurveillance microenvironment
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Ultra-stable Sb confined into N-doped carbon fibers anodes for high-performance potassium-ion batteries 被引量:15
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作者 Danyang Liu Li Yang +4 位作者 Zanyu Chen Guoqiang Zou Hongshuai Hou Jiugang Hu Xiaobo Ji 《Science Bulletin》 SCIE EI CAS CSCD 2020年第12期1003-1012,M0003,共11页
Antimony-based materials with high theoretical capacity are known as promising anodes for potassiumion batteries(PIBs). However, they still face challenges from the large ionic radius of the K ion, which has sluggish ... Antimony-based materials with high theoretical capacity are known as promising anodes for potassiumion batteries(PIBs). However, they still face challenges from the large ionic radius of the K ion, which has sluggish kinetics. Much effort is needed to exploit high-performance electrode materials to satisfy the reversible capacity of PIBs. In this paper, nano Sb confined in N-doped carbon fibers(Sb@CN nanofibers)were successfully prepared through an electrospinning method, which was designed to improve potassium storage performances. Sb@CN nanofibers benefit from the fact that the synergy between the porous nanofiber frame structure and the uniformly distributed Sb nano-components in the carbon matrix can effectively accelerate the ion migration rate and reduce the mechanical stress caused by K+insertion/extraction, Sb@CN nanofiber electrodes thus exhibited excellent potassium storage performance, especially long cycle stability, as expected. When utilized as a PIB anode, they delivered high reversible capacity of 360.2 m Ah g-1 after 200 cycles at 50 m A g-1, and a particularly stable capacity of 212.7 m Ah g-1 was also obtained after 1000 cycles even at 5000 m A g-1. Given such outstanding electrochemical performances,this work is expected to provide insight into the development and exploration of advanced alloy-type electrodes for PIBs. 展开更多
关键词 ELECTROSPINNING Sb@CN nanofibers Anode material Potassium-ion batteries
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