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Chemical Research in Chinese Universities 2006年第1期22卷 36-39页

作者： WU Chun-zan HUANG jia-xing zhang Qi-han XU jia-xi Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China

The reactions of 2,3-dihydro-1,5-benzothiazepines with ethoxyearbonylcarbene undergo complex rearrangements to produce rlng-opening and ring contraction products. Previously it was presumed that the different products were formed via different mechanisms depending on the kind of substituents at the 2-position of 1,5-benzothiazepines. However, on the basis of the further detailed investigation, it was found that all 1,5-benzothiazepines can undergo the same rearrangement to yield both ring-opening and ring contraction products.

关键词： 1,5-Benzothiazepine Ethoxycarbonylcarbene Rearrangement Ring-contraction Ring-opening

Realizing Majorana fermion modes in the Kitaev model

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Chinese Physics B 2021年第11期30卷 117-130页

作者： Lu Yang jia-xing zhang Shuang Liang Wei Chen Qiang-Hua Wang National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Institute of Physics Chinese Academy of SciencesBeijing 100190China

We study the possibility to realize a Majorana zero mode that is robust and may be easily manipulated for braiding in quantum computing in the ground state of the Kitaev model in this *** achieve this we first apply a uniform[111]magnetic field to the gapless Kitaev model and turn the Kitaev model to an effective p+ip topological superconductor of *** then study possible vortex binding in such system to a topologically trivial spot in the ground *** consider two cases in the system:one is a vacancy and the other is a fully polarized *** show that in both cases,the system binds a vortex with the defect and a robust Majorana zero mode in the ground state at a weak uniform[111]magnetic *** distribution and asymptotic behavior of these Majorana zero modes are *** Majorana zero modes in both cases decay exponentially in space,and are robust against local perturbations and other Majorana zero modes far away,which makes them promising candidates for braiding in topological quantum computing.

关键词： Kitaev model Majorana fermion modes topological quantum computing

Preparation and Characterization of Chitosan Composite Membranes Crosslinked by Carboxyl-capped Poly(ethylene glycol)

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Chinese Journal of Polymer Science 2014年第2期32卷 236-244页

作者： Meng-tan Cai jia-xing zhang 陈元维 Jun Cao Meng-tian Leng Shao-dong Hua 罗祥林 College of Polymer Science and Engineering Sichuan University State Key Laboratory of Polymer Materials and Engineering Sichuan University

In this study a series of chemically crosslinked chitosan/poly（ethylene glycol）（CS/PEG） composite membranes were prepared with PEG as a crosslinking reagent other than an additional blend. First, carboxyl-eapped poly（ethylene glycol）（HOOC-PEG-COOH） was synthesized. Dense CS/PEG composite membranes were then prepared by casting/evaporation of CS and HOOC-PEG-COOH mixture in acetic acid solution. Chitosan was chemically crosslinked due to the amidation between the carboxyl in HOOC-PEG-COOH and the amino in chitosan under heating, as confirmed by FTIR analysis. The hydrophilicity, water-resistance and mechanical properties of pure and crosslinked chitosan membranes were characterized, respectively. The results of water contact angle and water absorption showed that the hydrophilicity of chitosan membranes could be significantly improved, while no significant difference of weight loss between pure chitosan membranes and crosslinked ones was detected, indicating that composite membranes with amidation crosslinking possess excellent water resistanance ability. Moreover, the tensile strength of chitosan membranes could be significantly enhanced with the addition of certain amount of HOOC-PEG-COOH crosslinker, while the elongation at break didn＇t degrade at the same time. Additionally, the results of swelling behaviors in water at different pH suggested that the composite membranes were pH sensitive.

关键词： Chitosan Membrane Poly(ethylene glycol) Crosslink.

Degradation of o-dichlorobenzene by DBD-NTP co-modified titanium gel catalyst

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Journal of Environmental Sciences 2024年第9期143卷 71-84页

作者： Wenbo zhang Yi xing Wei Su jiaqing Wang Haoqi jia Yongkang Cui Jing Chen Hui zhang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants University of Science and Technology BeijingBeijing 100083China Guangdong Province Engineering Laboratory for Air Pollution Control Guangzhou 510530China College of Environmental and Resource Sciences Shanxi UniversityTaiyuan 030006China Sinosteel Maanshan Mine Research Institute Co.Ltd. Anhui 243071China

In order to study the degradation process of dioxins in industrial flue gas,the decomposition of o-dichlorobenzene(o-DCB)in a DBD plasma catalytic reactor was *** results showed that an NTP-catalyzed system,especially using the Cu Mn Ti Oxcatalyst,had better o-DCB degradation performance compared to plasma *** combination of the Cu Mn Ti Oxcatalyst with NTP can achieve a degradation efficiency of up to 97.2%for o-DCB;the selectivity of CO and CO_(2)and the carbon balance were 40%,45%,and 85%,*** dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o-DCB,and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge *** to the O1s XPS and O_(2)-TPD results,the conversion of CO to CO_(2)follows the M-v-K mechanism;thus,the active species on the catalyst surface play an important ***,the Cu Mn Ti Oxand NTP mixed system exhibited excellent stability,which is probably because Cu doping improved the lifetime of the *** work can provide an experimental and theoretical basis for research in the degradation of o-DCB by plasma catalyst systems.

关键词： o-dichlorobenzene(o-DCB) Non-thermal plasma catalysis Ozone concentration

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： Yang Lu jian-Xin Deng Zhi-Hui zhang jia-xing Wu Ran Wang Yi-Chen Bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1%,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-Ming An Yi-Ping Wang Tang-Song Zhu Chong xing Xu-Dong jia Qiu-Hong zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

Pd Pt VO_(x)/CeO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

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Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： jia Wang Yuxi Liu Jiguang Deng Lin Jing Xiuqing Hao xing zhang Xiaohui Yu Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/CeO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： Ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance

Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-Ming Cao Kai-Yang zhang jia-Lin Yang Zhen-Yi Gu xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries

Underestimated benefits of NO_(x) control in reducing SNA and O_(3) based on missing heterogeneous HONO sources

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 57-67页

作者： Shuping zhang Haotian Zheng Jun Liu Yao Shi Tianzeng Chen Chaoyang Xue Fenfen zhang Yueqi jiang Xiangping zhang Shovan Kumar Sahu Biwu Chu jia xing State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China China Academy of Civil Aviation Science and Technology Beijing 100028China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Yellow River Institute of Hydraulic Research Zhengzhou 450003China Centre for Climate Research Singapore Meteorological Service SingaporeSingapore 537054Singapore

Substantial NO_(x) emission mitigation is crucial for the synergistic reduction of particulate matter and ozone(O_(3))pollution in *** traditional air quality model does not consider heterogeneous HONO chemistry,leading to uncertainties in estimating the benefits of NO_(x) *** studies have shown that the parameterization of heterogeneous HONO formation increases both the simulated value of sulfate–nitrate–ammonium(SNA)and that of O_(3),thus adding the heterogeneous reactions of HONO into air quality models inevitably leads to changes in the estimated benefits of NO_(x) *** we investigated the changes in SNA and O_(3)concentrations from NO_(x) emission reduction before and after adding heterogeneous HONO reactions in the Community Multi-Scale Air Quality(CMAQ)*** heterogeneous HONO reactions in the simulation improved the benefits of NO_(x) reduction in terms of SNA control in *** 80%NO_(x) reduction,the reduction in SNA increased from 36.9%without considering heterogeneous HONO reactions to 42.8%with heterogeneous HONO *** reduction in the maximum daily 8h average(MDA8)O_(3)in summer caused by NO_(x) reduction increased slightly from 4.7%to 5.2%after adding heterogeneous HONO *** results in this study highlight the enhanced effectiveness of NO_(x) controls for the reduction of SNA and O_(3)after considering heterogeneous HONO formation in a complex chemical ambient,demonstrating the importance of NO_(x) controls in reducing PM2.5 and O_(3)pollution in China.

关键词： Heterogeneous HONO NO_(x) reduction PM_(2.5) O_(3)

An optimization-oriented modeling approach using input convex neural networks and its application on optimal chiller loading

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Building Simulation 2024年第4期17卷 639-655页

作者： Shanshuo xing Jili zhang Song Mu Dalian University of Technology Dalian116024China Guangdong Airport Baiyun Information Technology Co. Ltd.Guangzhou510000China

Optimization for the multi-chiller system is an indispensable approach for the operation of highly efficient chiller *** optima obtained by model-based optimization algorithms are dependent on precise and solvable objective *** classical neural networks cannot provide convex input-output mappings despite capturing impressive nonlinear fitting capabilities,resulting in a reduction in the robustness of model-based *** this paper,we leverage the input convex neural networks(ICNN)to identify the chiller model to construct a convex mapping between control variables and the objective function,which enables the NN-based OCL as a convex optimization problem and apply it to multi-chiller optimization for optimal chiller loading(OCL).Approximation performances are evaluated through a four-model comparison based on an experimental data set,and the statistical results show that,on the premise of retaining prior convexities,the proposed model depicts excellent approximation power for the data set,especially the unseen ***,the ICNN model is applied to a typical OCL problem for a multi-chiller system and combined with three types of optimization *** with conventional and meta-heuristic methods,the numerical results suggest that the gradient-based BFGS algorithm provides better energy-saving ratios facing consecutive cooling load inputs and an impressive convergence speed.

关键词： chiller plant input convex neural network optimal load distribution convex optimization