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Protecting-group-free enantioselective tandem allylic substitution of o-phenylenediamines and o-aminophenols

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Green Synthesis and Catalysis 2022年第2期3卷 185-189页

作者： xuehua kang Chao Qian He Yang Jicheng Shi Jerome Claverie Wenjun Tang School of Physical Science and Technology Shanghai Tech UniversityShanghai 200031China State Key Laboratory of Bio-Organic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China College of Chemistry Maoming Technology Center of Organic MaterialsGuangdong University of Petrochemical TechnologyMaoming 525000China School of Chemistry and Material Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Chemistry University of SherbrookeSherbrooke J1K2R1Canada

A protecting-group-free enantioselective tandem allylic substitution of o-phenylenediamines and o-aminophenols is realized for the first time with a Pd-WingPhos catalyst,providing expedient access to a series of chiral vinylsubstituted heterocycles in excellent ee and yields under mild reaction *** protocol is applied successfully to the synthesis of a cholesteryl ester transfer protein(CETP)inhibitor.

关键词： Tandem allylic substitution WingPhos Protecting-group-free Palladium catalysis Enantioselectivity

Optimization Method for Electrical Water Heaters Considering Shifting Potentials of Electricity Consumption and Water-use Activities

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1250-1259页

作者： Yuqing Bao Zhonghui Zuo xuehua Wu School of Electrical and Automation Engineering Nanjing Normal UniversityNanjing 210046China School of Electrical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210023China

Electrical water heaters(EWHs)are important can-didates to provide demand-response *** traditional op-timization method for EWHs focuses on the optimization of the electricity consumption,without considering the shifting poten-tial of the water-use *** paper proposes an optimiza-tion method for EWHs considering the shifting potentials of both the electricity consumption and water-use ***-sidering that the water-use activities could be monolithically shifted,the shifting model of the water-use activities was *** addition to the thermodynamic model of the EWH,the optimal scheduling model of the EWH was developed and solved using mixed-integer linear *** studies were performed on a single EWH and aggregate EWHs,demon-strating that the proposed method can shift the water-use activi-ties and therefore increase the load-shifting potential of the EWHs.

关键词： Electrical water heater(EWH) demand response load-shifting water-use activity

Vision-Based Adaptive Prescribed-Time Control of UAV for Uncooperative Target Tracking with Performance Constraint

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Journal of Systems Science & Complexity 2024年第5期37卷 1956-1977页

作者： SHE xuehua MA Hui REN Hongru LI Hongyi School of Automation and the Guangdong Provincial Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology School of Mathematics and Statistics Guangdong University of Technology College of Electronic and Information Engineering and Chongqing Key Laboratory of Generic Technology and System of Service Robots Southwest University

This paper discusses the uncooperative target tracking control problem for the unmanned aerial vehicle(UAV) under the performance constraint and scaled relative velocity constraint, in which the states of the uncooperative target can only be estimated through a vision sensor. Considering the limited detection range, a prescribed performance function is designed to ensure the transient and steady-state performances of the tracking system. Meanwhile, the scaled relative velocity constraint in the dynamic phase is taken into account, and a time-varying nonlinear transformation is used to solve the constraint problem, which not only overcomes the feasibility condition but also fails to violate the constraint boundaries. Finally, the practically prescribed-time stability technique is incorporated into the controller design procedure to guarantee that all signals within the closed-loop system are *** is proved that the UAV can follow the uncooperative target at the desired relative position within a prescribed time, thereby improving the applicability of the vision-based tracking approach. Simulation results have been presented to prove the validity of the proposed control strategy.

关键词： Nonlinear transformation performance constraint prescribed-time tracking uncooperative target vision-based measurement

Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta

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Research in Cold and Arid Regions 2024年第1期16卷 30-44页

作者： xuehua Cen Hua Zhang College of Geography and Environmental Science Northwest Normal UniversityLanzhouGansu 730070China

The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.

关键词： Land use change Multi-scenario simulation Ecosystem services Ecological security pattern The Yellow River Delta Circuit theory

Research progress on preparation of cerium-based oxide catalysts with specific morphology and their application for purification of diesel engine exhaust

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Journal of Rare Earths 2024年第7期42卷 1187-1216,I0001页

作者： Chunlei Zhang Siyu Gao Di Yu Shengran Zhou Lanyi Wang xuehua Yu Zhen Zhao Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang110034China State Key Laboratory of Heavy Oil Processing China University of PetroleumBejing102249China

The elimination of pollutants from diesel exhaust has received widespread research attention as they cause serious air pollution and pose a threat to human *** post-treatment technology is one of the most effective and universal technologies to treat diesel exhaust *** design and development of efficient and low-cost catalysts is the key factor to realize the wide application of catalytic post-treatment ***(Ce)-based oxides with specific morphologies are widely used to eliminate pollutants in diesel vehicle exhaust due to their unique physical and chemical properties,such as high catalytic activity,low cost and *** this review,the preparation methods of Cebased oxide materials with specific morphologies,such as nanoparticles,nanocubes,nanorods,nanofibers,and multi-stage pores,are introduced in detail,and the research progress on using these catalysts for the removal of carbon monoxide,hydrocarbons,soot particles,nitrogen oxides,and other pollutants from diesel exhaust is reviewed in ***,the unresolved issues associated with using Ce-based oxide catalysts with a specific morphology to catalytically remove pollutants from diesel exhaust are highlighted,and future application prospects and development directions are discussed.

关键词： Ce-based oxide catalysts Dies elexhaust pollutants Specific morphology Catalytic purification Rare earths

Effective integration of highly-efficient focusing apodized grating and quantum dots on a solid substrate for scalable quantum photonic circuits

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 99-107页

作者： Beimeng Yao Rongbin Su Shunfa Liu Changkun Song Ying Yu Jin Liu xuehua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China

Recent advancements in quantum photonic circuits have significantly influenced the field of quantum information *** pursuit of an integrated quantum photonic circuit that offers an active,stable platform for large-scale integration and high processing efficiency remains a key *** grating coupler,as a crucial element for an efficient transformation output interface in the integrated quantum photonic circuits,presents significant potential for practical ***,we demonstrate the integration block of a highly efficient shallow-etched focusing apodized grating coupler with indium arsenide(InAs)quantum dots(QDs)in gallium arsenide(GaAs)on a SiO2substrate for active quantum photonic *** designed grating couplers possess a high efficiency over 90% in the broadband(900-930 nm)from the circuit to free space,and a nearly-perfect match with the fiber ***,the efficiency to free space reaches 81.8%,and the match degree with the fiber mode is high up to 92.1%.The proposed integration block offers the potential for large-scale integration of active quantum photonic circuits due to its stable solid substrate and highly performant output for quantum measurements.

关键词： quantum dot grating coupler wafer bonding quantum photonic circuit

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Supersaturation-driven self-assembly formation of ceftriaxone sodium spherulites:From amorphous form to spherulites

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Particuology 2024年第7期90卷 10-19页

作者： Shankun Liang Yuchao Niu Xueyan Hu Wu Xiao xuehua Ruan Gaohong He Xiaobin Jiang State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsSchool of Chemical EngineeringDalian University of TechnologyDalian116024China School of Chemical Engineering at Panjin Dalian University of TechnologyPanjin124221China

Drug particles with spherical morphology possess amazing advantages in terms of particle flowability,mechanical properties,drug solubility,and *** growth mechanism of drug spherulite is of great importance for the preparation and regulation of ***,ceftriaxone sodium spherulites were fabricated by the antisolvent crystallization method using dropwise addition of ceftriaxone sodium solution to *** observation of the whole crystallization process combined with electron microscopy technique revealed the spherical growth process from amorphous form to *** the supersaturation of the crystallization system was adjusted,the ceftriaxone sodium crystals transformed from amorphous form to *** the process of antisolvent crystallization with acetone as antisolvent,when the theoretical supersaturation degree S was higher than 2.62,the crystallization system tended to appear amorphous form;when S was between 2.57 and 2.62,the amorphous form transformed into clustered spherulites;when S was less than 2.57,the surface of spherulites will be covered with flaky crystal,which transformed into urchin-like *** the understanding of the spherical growth mechanism,the ceftriaxone sodium spherulites prepared in this research with modified supersaturation control had a low residue of antisolvent acetone,and the flowability was significantly improved.

关键词： Spherulite Ceftriaxone sodium Antisolvent crystallization Supersaturation Online observation

Two UV organic-inorganic hybrid antimony-based materials with superior optical performance derived from cation-anion synergetic interactions

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Chinese Chemical Letters 2024年第9期35卷 442-446页

作者： Pu Zhang Xiang Mao xuehua Dong Ling Huang Liling Cao Daojiang Gao Guohong Zou College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610066China College of Chemistry Sichuan UniversityChengdu 610065China

Finding suitable strategies to effectively enhance the optical properties of materials are the goal being pursued by ***,cation-anion synergetic interactions strategy was proposed to develop two novel organic-inorganic hybrid antimony-based optical materials,(C_(3)H_(5)N_(2))Sb F_(2)SO_(4)(I)and(C_(5)H_(6)N)Sb F_(2)SO_(4)(Ⅱ),which were obtained by introducing Sb^(3+)cation containing stereochemically active lone-pair(SCALP)and organicπ-conjugated cations into sulphate *** synergistic interactions of the organicπ-conjugated cations,the inorganic[SbO_(2)F_(2)]^(3-)seesaw anions and the[SO_(4)]^(2-)distorted tetrahedra anions make their ultraviolet(UV)absorption edges approach 297 and 283 nm,respectively,and raise their birefringence up to 0.193@546 nm and 0.179@546 nm,***,although the two compounds have the same stoichiometric ratio and similar one-dimensional(1D)chain structure,they show opposite macroscopic symmetry,where the NCS compound(Ⅱ)exhibits a large secondharmonic generation(SHG)response(1.6 times that of KH_(2)PO_(4)).The two reported compounds are found to be promising UV optical materials in the experimental tests.

关键词： Antimony-based crystals Cation-anion synergetic interactions Large birefringence Short UV absorption edge Organic-inorganic hybrid Ionothermal synthesis

Insight into the synergistic effect of defect and strong interface coupling on ZnIn_(2)S_(4)/CoIn_(2)S_(4)heterostructure for boosting photocatalytic H_(2) evolution

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Journal of Energy Chemistry 2024年第5期92卷 151-161页

作者： xuehua Wang Tianyu Shi Xianghu Wang Aili Song Guicun Li Lei Wang Jianfeng Huang Alan Meng Zhenjiang Li College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina Qingdao Huanghai University Qingdao 266000ShandongChina School of Material Science and Engineering International S&T Cooperation Foundation of Shaanxi ProvinceXi’an Key Laboratory of Green Manufacture of Ceramic MaterialsShaanxi University of Science and TechnologyXi’an 710021ShaanxiChina

Steering the directional carrier migration across the interface is a central mission for efficient photocatalytic *** this work,an atomic-shared heterointerface is constructed between the defect-rich ZnIn_(2)S_(4)(HVs-ZIS)and CoIn_(2)S_(4)(CIS)via a defect-guided heteroepitaxial growth *** strong interface coupling induces adequate carriers exchanging passageway between HVs-ZIS and CIS,enhancing the internal electric field(IEF)in the ZnIn_(2)S_(4)/CoIn_(2)S_(4)(HVs-ZIS/CIS)*** defect structure in HVs-ZIS induces an additional defect level,improving the separation efficiency of ***,promoted by the IEF and intimate heterointerface,photogenerated electrons trapped by the defect level can migrate to the valence band of CIS,contributing to massive photogenerated electrons with intense reducibility in HVs-ZIS/***,the HVs-ZIS/CIS heterostructure performs a boosted H_(2)evolution activity of 33.65 mmol g^(-1)h^(-1).This work highlights the synergistic effects of defect and strong interface coupling in regulating carrier transfer and paves a brave avenue for constructing efficient heterostructure photocatalysts.

关键词： Defect-guided heteroepitaxial growth Heterointerface coupling Photocatalytic H_(2)evolution Mechanism HVs-ZIS/CIS