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Review on birefringence in borates based on birefringence-active functional groups and arrangements

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Science China Chemistry 2024年第7期67卷 2155-2170页

作者： Qianzhen zhang Ran An Zhihua Yang Xifa long Shilie Pan Yun Yang Research Center for Crystal Materials State Key Laboratory of Functional Materials and Devices for Special Environmental ConditionsXinjiang Key Laboratory of Functional Crystal MaterialsThe Xinjiang Technical Institute of Physics&ChemistryChinese Academy of SciencesUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical *** big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical *** design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology ***,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly *** is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence.

关键词： birefringence borate optical functional crystal structural anisotropy arrangement of functional units

Electrical control of excitonic oscillator strength and spatial distribution in a monolayer semiconductor

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Nano Research 2024年第9期17卷 8424-8430页

作者： Yanming Wang Junrong zhang Tianhua Ren Meng Xia long Fang xiangyi Wang Xingwang zhang Kai zhang Junyong Wang School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Nanophotonic Materials and Devices&Key Laboratory of Nanodevices and Applications i-LabSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123China Institute of Applied Physics and Materials Engineering University of MacaoTaipaMacao 999078China College of New Energy Inner Mongolia University of TechnologyHohhot 010051China

Electrical modulation of luminescence is significant to modern light-emitting *** transition metal dichalcogenides are emerging direct-bandgap luminescent materials with unique excitonic properties,and the multiple exciton complexes provide new opportunities to modulate the property of luminescence in atomically thin ***,we report an electrical control of exciton emission in the oscillator strength and spatial distribution of excitons in a monolayer *** modulation of excitonic emission intensity with a degree of modulation of~92%has been demonstrated by an electric field at room *** spatial carrier redistribution tuned by a lateral electric field results in distinct excitonic emission patterns by *** modulation approach to exciton oscillator strength and distribution provides an efficient way to investigate the exciton diffusion dynamics and to construct electrically tunable optoelectronic devices.

关键词： monolayer semiconductor exciton electrical modulation spatial distribution

Damage on intestinal barrier function and microbial detoxification of deoxynivalenol:A review

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Journal of Integrative Agriculture 2024年第8期23卷 2507-2524页

作者： Jia Chen Xinran zhang Ziqi He Dongwei Xiong Miao long Key Laboratory of Livestock Infectious Diseases Ministry of Education/College of Animal Science and Veterinary Medicine ShenyangAgricultural UniversityShenyang 110866China

Deoxynivalenol(DON)is a mycotoxin that is produced by various species of Fusarium and is ubiquitous in food and *** low concentrations,it can cause metabolic disorders in animals and humans and,at high concentrations,it can lead to pathological changes in the *** impact of DON on human/animal health and animal productivity has thus attracted a great deal of attention around the *** causes severe damage to the intestine,including compromised intestinal barrier,mucosal damage,weakened immune function,and alterations in gut microbiota *** effects exacerbate intestinal infections and inflammation in livestock and poultry,posing adverse effects on overall ***,research into biological methods for DON detoxification is a crucial avenue for future *** includes the utilization of adsorption,enzymatic degradation,and other biological approaches to mitigate DON's impact,offering new strategies for prevention and treatment of DON-induced *** research will focus on identifying highly efficient detoxifying microorganisms or enzymes to reduce DON levels in food and feed,thereby mitigating its risks to both animals and human health.

关键词： deoxynivalenol(DON) intestinal barrier function mucus barrier immune function flora composition biological detoxification

Optimized Auxiliary Frequency Control of Wind Farm Based on Piecewise Reduced-order Frequency Response Model

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 791-802页

作者： Xu zhang Chen Zhao Junchao Ma long zhang Dan Sun Chenxu Wang Yan Peng Heng Nian the School of Electrical Engineering Zhejiang UniversityHangzhou 310058China Electric Power Research Institute of State Grid Zhejiang Electric Power Corporation Hangzhou 310014China

With the increasing wind power penetration in the power system,the auxiliary frequency control(AFC)of wind farm(WF)has been widely *** traditional system frequency response(SFR)model is not suitable for the wind power generation system due to its poor accuracy and *** this paper,a piecewise reduced-order frequency response(PROFR)model is proposed,and an optimized auxiliary frequency control(O-AFC)scheme of WF based on the P-ROFR model is ***,a full-order frequency response model considering the change in operating point of wind turbine is established to improve the *** order to simplify the fullorder model,a P-ROFR model with second-order structure and high accuracy at each frequency response stage is *** on the proposed P-ROFR model,the relationship between the frequency response indexes and the auxiliary frequency controller coefficients is expressed ***,an OAFC scheme with the derived explicit expression as the optimization objective is proposed in order to improve the frequency support capability on the premise of ensuring the full release of the rotor kinetic energy and the full use of the effect of time delay on frequency ***,the effectiveness of the proposed P-ROFR model and the performance of the proposed OAFC scheme are verified by simulation studies.

关键词： Frequency response piecewise reduced-order wind farm auxiliary frequency control

Highly efficient catalyst for 1,1,2-trichloroethane dehydrochlorination via BN_(3) frustrated Lewis acid-base pairs

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Nano Research 2024年第6期17卷 4773-4781页

作者： Yuxue Yue Fangmin Zuo Bolin Wang Xiaoling xian Jun Tang Haifeng zhang Zilong zhang Qingping Ke Wei Chen School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China Industrial Catalysis Institute of Zhejiang University of Technology Hangzhou 310014China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China

In this study,a novel non-metallic carbon-based catalyst co-doped with boron and nitrogen(B,N)was successfully *** precisely controlling the carbonization temperature of a binary mixed ionic liquid,we selectively modified the doping site structure,ultimately constructing a B,N co-doped frustrated Lewis acid-base pair *** catalyst exhibited remarkable catalytic activity,selectivity,and stability in the dehydrochlorination reaction of 1,1,2-trichloroethane(TCE).Detailed characterization and theoretical calculations revealed that the primary active center of this catalyst was the BN_(3)*** to conventional graphitic N structures,the BN_(3)structure had a higher p-band center,ensuring superior adsorption and activation capabilities for TCE during the *** the BN_(3)site,three negatively charged nitrogen atoms acted as Lewis bases,while positively charged boron atoms acted as Lewis *** synergistic interaction facilitated the specific dissociation of chlorine and hydrogen atoms from TCE,significantly enhancing the 1,1-dichloroethene *** this research,we not only explored the active site structure and catalytic mechanism of B,N co-doped catalysts in depth but also provided an efficient,selective,and stable catalyst for the dehydrochlorination of TCE,contributing significantly to the development of non-metallic catalysts.

关键词： B N co-doped sites dehydrochlorination frustrated Lewis acid-base pairs catalytic mechanism

Neural Dynamics for Cooperative Motion Control of Omnidirectional Mobile Manipulators in the Presence of Noises: A Distributed Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1605-1620页

作者： Yufeng Lian Xingtian Xiao Jiliang zhang long Jin Junzhi Yu Zhongbo Sun the Department of Control Engineering Changchun University of TechnologyChangchun 130012China IEEE the College of Information Science and Engineering Northeastern UniversityShenyang 110819 the National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China the School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China the State Key Laboratory for Turbulence and Complex Systems Department of Advanced Manufacturing and RoboticsCollege of EngineeringPeking UniversityBeijing 100871China

This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing single-agent motion control to cater to scenarios involving the cooperative operation of MOMMs. Specifically, squeeze-free cooperative load transportation is achieved for the end-effectors of MOMMs by incorporating cooperative repetitive motion planning(CRMP), while guiding each individual to desired poses. Then, the distributed scheme is formulated as a time-varying quadratic programming(QP) and solved online utilizing a noise-tolerant zeroing neural network(NTZNN). Theoretical analysis shows that the NTZNN model converges globally to the optimal solution of QP in the presence of noise. Finally, the effectiveness of the control design is demonstrated by numerical simulations and physical platform experiments.

关键词： Cooperative motion control noise-tolerant zeroing neural network(NTZNN) omnidirectional mobile manipulator(OMM) repetitive motion planning

High-entropy materials:Excellent energy-storage and conversion materials in the field of electrochemistry

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Particuology 2024年第9期92卷 42-60页

作者： Jincan Li Huiyu Duan Qi long Bianjiang zhang Changyun Chen Huan Pang Key Laboratory of Advanced Functional Materials of Nanjing School of Environmental ScienceNanjing Xiaozhuang UniversityNanjing211171China School of Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou225009China

High-entropy materials(HEMs),a new type of materials,have attracted significant attention in the field of electrocatalytic reactions,batteries and energy-storage materials over the past few years owing to their unique structure,controllable elementary composition,and adjustable *** excellent characteristics result from four major factors:high entropy,sluggish-diffusion,severe lattice distortion,and cocktail effect,and are used widely in energy-energy *** review aims to summarize the recent progress of HEMs in electrochemical *** begin with the concept,structure,and four core effects of HEMs that provide the basic information on ***,we discuss the major properties of HEMs and analyze the relationship between their structures and ***,we highlight the outstanding performance of HEMs in hydrogen storage,electrode materials of batteries,catalysis,and supercapacitors,and briefly explain the mechanisms of these materials that are crucial in energy storage and *** review will assist in understanding the excellent energy-storage properties,intricacies of the phase structures,elemental interactions,and reaction mechanisms associated with ***,challenges and future development prospects are *** work will provide insight into the factors that are crucial for designing HEMs with energy storage properties.

关键词： High-entropy materials Hydrogen storage Electrode materials of batteries Catalyst Supercapacitor

Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements

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Defence Technology（防务技术） 2024年第2期32卷 473-484页

作者： Yiming zhang Ningfei Wang Weihua Ma Ran Wang long Bai Yi Wu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing System Design Institute of Electro-mechanic Engineering Beijing 100854China Xi'an Changfeng Research Institute of Mechanism and Electricity Xi'an 710065China

In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were *** projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 *** onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and *** compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching *** the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant *** calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were *** dynamic mechanical response process of the dummy propellant grain was analysed in *** results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.

关键词： Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response

Treatment of allergic airway inflammation and hyperrespon-siveness by imiquimod modulating transcription factors T-bet and GATA-3

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Chinese Medical Journal 2006年第8期119卷 640-648页

作者： BIAN Tao YIN Kai-sheng JIN Shu-xian zhang Xi-long ZHOU Jin-yong MA Xiu-qin HU Jing-jing DE Wei Department of Respiratory Medicine First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Background Imiquimod is an imidazoquinoline, which class of compounds are known to have antiviral and antitumoural properties. In recent studies, it was shown that imiquimod modulates the T helper cell type Th1/Th2 response by inducing the production of Thl cytokines like IFN-γ, and by inhibiting the Th2 cytokines like interleukin （IL）-4. Several investigators have shown that T-bet and GATA-3 are master Thl and Th2 regulatory transcription factors. This study investigated whether irniquimod treatment inhibited airway inflammation by modulating transcription factors T-bet and GATA-3. Methods Thirty-six male SD rats were randomly divided into a control group, an asthmatic group, and an imiquimod group, which was exposed to an aerosol of 0.15% imiquimod. Twenty-four hours after the last ovalbumin （OVA） challenge, airway responsiveness was measured and changes in airway histology were observed. The concentrations of IL-4, IL-5 and IFN-γ in bronchoalveolar lavage fluid （BALF） and serum were measured by enzyme linked immunosorbent assay （ELISA）. The rnRNA expressions of IL-4, IL-5, IFN-γ, T-bet and GATA-3 in lung and in CD4^＋ T cells were determined by reverse transcription polymerase chain reaction （RT-PCR）. The protein expressions ofT-bet and GATA-3 were measured by Western blot. Results It was demonstrated that imiquimod 1） attenuated OVA induced airway inflammation; 2） diminished the degree of airway hyperresponsiveness （AHR）; 3） decreased the Th2 type cytokines and increased Thl type cytokines mRNA and protein levels; 4） modulated the Th1/Th2 reaction by inhibiting GATA-3 production and increasing T-bet production. Conclusion Imiquimod treatment inhibits OVA induced airway inflammation by modulating key master switches GATA-3 and T-bet that result in committing T helper cells to a Thl phenotype.

关键词： asthma T-bet GATA-3 imiquimod