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Science China Chemistry 2006年第2期49卷 140-147页

作者： zhang Fumin WANG Jun yuan Chaoshu ren Xiaoqian Key Laboratory of Materials-Oriented Chemical Engineering of Jiangsu Province College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China

A series of catalysts of 12-Phosphotungstic acid(PW)and its cesium salts immobilizedon dealuminated ultra-stable Y zeolite(DUSY)were *** specific surface area and acidstrength were characterized,and their catalytic activity,selectivity and stability were evaluated in theliquid-phase esterification of acetic acid with *** was found that the catalytic activity could beimproved remarkably by introducing PW onto dealuminated USY(from 49.5%to 86.4%).Howeverthis obvious promotion effect of PW could not be observed on USY supported PW catalyst,whichshowed rather low conversion of less than 25.0%.The supported cesium salt of PW on DUSY catalysgave a very high conversion of n-butanol of 94.6%and the 100%selectivity for n-butyl *** stability test revealed that after 5 reaction cycles,the catalytic activity over PW/DUSY drastically dropped to 47.6%,by contrast,the PW cesium salt/DUSY still showed a high conversion o81.6%.The leaching test for catalysts in water showed that the decrease of activity was closely associated with the solubility of the active heteropoly components on supports into the polar solvent,whichindicates that the catalytic deactivation was mainly due to the lose of the heteropoly species in thereaction *** high catalytic stability of the supported cesium salts of PW is suggested to bederived from the water-tolerance of cesium salts of PW in the polar reaction system.

关键词： heteropoly acid 12-phosphotungstic acid Cs-salts of 12-phosphotungstic acid USY esterification n-butanol.

Molecular engineering of ultra-sensitive fluorescent probe with large Stokes shift for imaging of basal HOCl in tumor cells and tissues

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Chinese Chemical Letters 2020年第11期31卷 2980-2984页

作者： Peng Lu Xingxing zhang Tianbing ren Lin yuan State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Fluorescent probes have been widely employed in biological imaging and ***,it is always a challenge to design probes with high *** this work,based on rhodamine skeleton,we developed a general strategy to construct sensitivity-enhanced fluorescent probe with the help of theoretical calculation for the first *** a proof of concept,we synthesized a series of HOCl *** results showed that with the C-9 of pyronin moiety of rhodamine stabilized by an electron donor group,probe DQF-S exhibited an importantly enhanced sensitivity(LOD:0.2 nmol/L)towards HOCl together with fast response time(650 nm)and large Stokes *** studies indicated that DQF-S can not only effectively detect basal HOCl in various types of cells,but also be successfully applied to image tumor tissue in *** results demonstrate the potential of our design as a useful strategy to develop excellent fluorescent probes for bioimaging.

关键词： Fluorescent probes High sensitivity Hypochlorous acid(HOCl) Large Stokes shift Fluorescence imaging

Tiny MEMS-Based Pressure Sensors in the Measurement of Intracranial Pressure

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Tsinghua Science and Technology 2014年第2期19卷 161-167页

作者： Yanhang zhang Zhaohua zhang Bo Pang Li yuan Tianling ren the Institute of Microelectronics Tsinghua University the Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences

This study presents a tiny pressure sensor which is used to measure the Intracranial Pressure （ICP）. The sensor is based on the piezoresistive effect. The piezoresistive pressure sensor is simulated and designed by using nonlinear programming optimizing and Finite Element Analysis （FEA） tools. Two kinds of sensor sizes are designed in the case of childhood and adult. The sensors are fabricated by Microelectro Mechanical Systems （MEMS） process. The test results yield sensitivities of 1.033x 10-2 mV/kPa for the childhood type detection and 1.257x 10-2 mV/kPa for the adult detection with sensor chip sizes of 0.40x0.40 mm2 and 0.50x0.50 mm2, respectively. A novel method for measuring ICP is proposed because of the tiny sizes. Furthermore, relative errors for sensitivity of pressure sensors are limited within 4.76%. Minimum Detectable Pressure （MDP） reaches 128.4 Pa in average.

关键词： intracranial pressure tiny sensors finite element analysis

Rational design of far red to near-infrared rhodamine analogues with huge Stokes shifts for single-laser excitation multicolor imaging

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Chinese Chemical Letters 2021年第12期32卷 3890-3894页

作者： Xingxing zhang Tianbing ren Feiyu Yang Lin yuan State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Rhodamine dyes have been widely employed in biological imaging and sensing. However, it is always a challenge to design rhodamine derivatives with huge Stokes shift to address the draconian requirements of single-excitation multicolor imaging. In this work, we described a generally strategy to enhance the Stokes shift of rhodamine dyes by completely breaking their electronic symmetry. As a result, the Stokes shift of novel rhodamine dye DQF-RB-Cl is up to 205 nm in PBS, which is the largest in all the reported rhodamine derivatives. In addition, we successfully realized the single excitation trichromatic imaging of mitochondria, lysosomes and cell membranes by combining DQF-RB-Cl with commercial lysosomal targeting probe Lyso-Tracker Green and membrane targeting dye Dil. This is the organic synthetic dyes for SLE-trichromatic imaging in cells for the first time. These results demonstrate the potential of our design as a useful strategy to develop huge Stokes shift fluorophore for bioimaging.

关键词： Fluorescent dyes Rhodamine analogues Huge stokes shifts Single-laser excitation Multicolor imaging

Development of L-arginine-based poly(ester urethane)urea for enhanced vascular adaptability

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Science China(Technological Sciences) 2022年第11期65卷 2751-2762页

作者： BAI Shan zhang XiangYu ZANG LeiLei ren LiXia yuan XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

Mismatched biomechanical properties between artificial vascular grafts and native blood vessels can result in intimal hyperplasia,especially for the implantation of small-diameter blood *** biomaterials for vascular repair still remain *** poly(ε-caprolactone)(PCL)has been applied for the preparation of electrospun vascular grafts,but more efforts are needed to improve its compliance with tissue ***,L-arginine-based poly(ester urethane)urea(PEUU)with both elasticity and biodegradability was synthesized so as to enhance the biomechanical properties of vascular grafts by blending electrospinning with PCL in a given mass *** was exhibited that the prepared electrospun PCL/PEUU fibrous membranes were suitable for cell proliferation with normal cell *** importantly,the electrospun membrane with 1/1 mass ratio of PCL/PEUU(PEUU50)showed specific flexibility,exhibiting more suitable mechanical properties matching to the native blood ***,the PEUU50 electrospun membrane demonstrated significantly lower Young’s modulus(9.3±0.8 MPa)and tensile strength(6.0±0.5 MPa),and extremely higher elongation(389%±24%)in wet state than those(16.3±3.0 MPa,11.4±7.1 MPa and 196%±57%,respectively)of the pristine PCL ***,this study demonstrated the great potential of amino acid-based PEUUs for the application in small-diameter vascular grafts.

关键词： poly(ester urethane)urea poly(e-caprolactone) electrospinning vascular grafts mechanical properties

Sliding-Mode-Control Based Robust Guidance Algorithm Using Only Line-of-Sight Rate Measurement

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Journal of Systems Science & Complexity 2016年第6期29卷 1485-1504页

作者： CHEN Jian TIAN yuan LI Peng LI Qingdong ren zhang College of Engineering China Agricultural UniversityBeijing 100083China Beijing Institute of Space Long March Vehicle Beijing 100076China Halliburton Energy Services Inc. Houston 77032USA Science and Technology on Aircraft Control Laboratory Beijing University of Aeronautics and AstronauticsBeijing 100191China

Robust guidance algorithm using only line-of-sight rate measurement is proposed for the interceptor with passive *** initial relative distance,initial closing velocity and their error boundaries are employed to obtain their estimations according to the interceptor-target relative kinematics.A robust guidance law based on sliding mode control is formulated,in which the boundary of target maneuver is needed and the chattering phenomenon inevitably *** order to address the defects above,an estimation to the boundary of the target acceleration is proposed to improve the robust guidance law and the Lyapunov stability analysis is *** main feature of the robust guidance algorithm is that it reduces the influence of the relative distance,the closing velocity and the target maneuver on the interception and enhances the effect of line-of-sight *** two worst conditions of initial measured distance and initial measured closing velocity,performances of the proposed guidance laws are verified via numerical simulations against different target maneuvers.

关键词： Boundary of target maneuver line-of-sight rate Lyapunov stability robust guidancealgorithm sliding mode control.

FeNi doped porous carbon as an efficient catalyst for oxygen evolution reaction

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Frontiers of Chemical Science and Engineering 2021年第2期15卷 279-287页

作者： Jun-Wei zhang Hang zhang Tie-Zhen ren Zhong-Yong yuan Teresa JBandosz Hebei Provincial Key Laboratory of Green Chemical Technology&High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry and Biochemistry The City College of New YorkNew YorkNY 10031USA

Polymer-derived porous carbon was used as a support of iron and nickel species with an objective to obtain an efficient oxygen reduction reaction(OER)*** surface features were extensively characterized using X-ray diffraction,X-ray photoelectron spectroscopy and high-resolution transmission electron *** FeNi-modified carbon the overpotential for OER was very low(280 mV)and comparable to that on noble metal catalyst IrO_(2).The electrochemical properties have been investigated to reveal the difference between the binary alloy-and single metal-doped *** work demonstrates a significant step for the development of low-cost,environmentally-friendly and highly-efficient OER catalysts.

关键词： OER polystyrene salt porous carbon FeNi alloy p/n junction

Electronic and optical properties of GaN–MoS2 heterostructure from first-principles calculations

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Chinese Physics B 2019年第8期28卷 254-257页

作者： Dahua ren Xingyi Tan Teng zhang yuan zhang School of Information Engineering Hubei Minzu University

Heterostructures(HSs)have attracted significant attention because of their interlayer van der Waals *** electronic structures and optical properties of stacked GaN-MoS2 HSs under strain have been explored in this work using density functional *** results indicate that the direct band gap(1.95 e V)of the Ga N-MoS2 HS is lower than the individual band gaps of both the GaN layer(3.48 e V)and the MoS2 layer(2.03 eV)based on HSE06 hybrid functional ***,the GaN-MoS2 HS is a typical type-II band HS semiconductor that provides an effective approach to enhance the charge separation efficiency for improved photocatalytic degradation activity and water splitting *** tensile or compressive strain,the direct band gap of the GaN-MoS2 HS undergoes ***,the GaN-MoS2 HS maintains its direct band gap semiconductor behavior even when the tensile or compressive strain reaches 5%or-5%.Therefore,the results reported above can be used to expand the application of Ga N-MoS2 HSs to photovoltaic cells and photocatalysts.

关键词： GaN-MoS2 heterostructure electronic structures optical properties first-principles calculations

Fecal microbiota transplantation:whole grain highland barley improves glucose metabolism by changing gut microbiota

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Food Science and Human Wellness 2024年第4期13卷 2014-2024页

作者： Xin ren Fulong zhang Min zhang yuan Fang Zenglong Chen Meili Huan Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Engineering and Technology Research Center of Food AdditivesNational Grain Industry Highland Barley Deep Processing Technology Innovation CenterBeijing Technology and Business UniversityBeijing 100048China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China COFCO Nutrition and Health Research Institute Beijing 102209China

Highland barley(HB)is a high-altitude cereal with rich nutritional components and potential health *** clarify its hypoglycemic effect and mechanism,we investigated the effect of whole grain HB and fecal microbiota transplantation(FMT)on glucose metabolism and gut microbiota in high-fat diet and streptozotocin(HFD/STZ)-induced diabetic *** results showed that HB(40%)significantly decreased fasting blood glucose and the area under the glucose tolerance curve,significantly increased insulin secretion and improved insulin resistance in HFD/STZ-induced diabetic mice(P<0.05).Inflammatory factors and blood lipid indices were also significantly alleviated after 12 weeks of 40%HB intervention(P<0.05).Additionally,beneficial bacteria,such as Bifidobacterium and Akkermansia,were significantly enriched in the gut of diabetic mice after whole grain HB ***,the results of further FMT experiments verified that the fecal microbiota after the 40%HB intervention not only significantly increased the relative abundance of Bifidobacterium and Akkermansia but also effectively improved glucose metabolism and alleviated the inflammatory state in HFD/STZ-induced diabetic ***,our study confirmed the bridge role of gut microbiota in improving glucose metabolism of whole grain HB,which could promote the development of precision nutrition.

关键词： Highland barley Diabetes Glucose metabolism Gut microbiota Fecal bacteria transplantation

Ionic Liquid/Poly(ionic liquid)-based Semi-solid State Electrolytes for Lithium-ion Batteries

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Chinese Journal of Polymer Science 2020年第5期38卷 506-513,I0006页

作者： Deng-Zhou zhang Yong-yuan ren Yin Hu Liang Li Feng Yan Hubei Key Laboratory of Plasma Chemistry and Advanced Materials College of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Ionic liquids(ILs)have appeared as the most promising electrolytes for lithium-ion batteries,owing to their unique high ionic conductivity,chemical stability and thermal stability ***(ionic liquid)s(PILs)with both IL-like characteristic and polymer structure are emerging as an alternative of traditional *** this review,recent progresses on the applications of IL/PIL-based semi-solid state electrolytes,including gel electrolytes,ionic plastic crystal electrolytes,hybrid electrolytes and single-ion conducting electrolytes for lithium-ion batteries are discussed.

关键词： Ionic liquids Poly(ionic liquid)s Semi-solid state electrolytes Lithium-ion batteries