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Immobilizing Triphenylamine with Photoredox Inert Sr^(2+)Forming Sr-MOF with Controlled Electron Migration for Photocatalytic Oxidation of Thiols to Disulfides

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Chinese Journal of Chemistry 2024年第10期42卷 1093-1099页

作者： ying-Xia Wang Fang Zheng Dong-Xia Song Bao-Yue niu Lu-Qian Deng Xian-Ming Zhang Key Laboratory of Magnetic Molecules and Magnetic Information Materials(Ministry of Education) Schoolof Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi 030006China Key Laboratory of Interface Science and Engineering in Advanced Material(Ministry of Education) College of ChemistryTaiyuan University of TechnologyTaiyuanShanxi 030024China

The photocatalytic oxidative coupling of thiols is one of the most popular methods to synthesize the *** and its derivatives(TPAs)are promising for the above reaction,but suffer from the easy polymerization and difficult *** overcome these obstacles while controlling the photogenerated electrons transfer directly to target substrates,herein,we constructed one TPA-based metal-organic framework(MOF),(Me_(2)NH_(2))[Sr(TCBPA)]·DMA·3H_(2)O(1),by direct self-assembly of tris(4′-carboxybiphenyl)amine(H_(3)TCBPA)and photoredox inert strontium ion(Sr^(2+)).DFT calculations revealed that the valence band maximum(VBM)and the conduction band minimum(CBM)are mainly located on TCBPA^(3-),successfully inhibiting the undesirable electron migration to metal *** results indicated that 1 displays superior performance than homogeneous H_(3)TCBPA,which may result from the abundant π…π and C—H…π interactions between the well-arranged TCBPA^(3-)and the build-in electric field between the anionic framework and the Me_(2)NH^(2+).This work highlights that immobilizing TPAs into MOFs is one promising approach to designing heterogeneous photocatalysts for the synthesis of disulfides by oxidative coupling of thiols.

关键词： Triphenylamine Metal-organic frameworks Strontium Photooxidation Thiols Disulfides

Flexible piezoelectret film sensor for noncontact mechanical signal capture by multiple transmission media

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Nano Research 2024年第8期17卷 7643-7657页

作者： Xingchen Ma Qianqian Hu Lian Zhou Xinhao Xiang Yi Qin Ke Zhang Pengfei He ying Dai Wenxin niu Xiaoqing Zhang Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center) School of MedicineTongji UniversityShanghai 201619China Department of Rehabilitation Sciences Tongji University School of MedicineShanghai 200092China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

Mechanical signal capture without physical contact has emerged as a highly promising research field and attracted tremendous attention due to its prosperous applications in household medical care,lifestyle monitoring and remote operation,offering users high level of safety,convenience and ***,noncontact sensing is ideal to maximize the immersive user experience in the human–machine interaction(HMI),eliminating interference to human activities and mechanical fatigue to the sensor,***,we report a self-powered flexible sensor integrated with irradiation cross-linked polypropylene(IXPP)piezoelectret film for noncontact sensing,featuring multi-functions to detect mechanical signals transmitted through solid,liquid and gaseous media and would facilitate their versatile practical *** folded-structure configuration of the sensor facilitates the improvement of the noncontact sensing *** solid media,such as the rectangular wooden stick used in this study,the sensor can detect mechanical stimulus exerted at a distance of 100 cm.A system detection sensitivity up to 57 pC/kPa with a low detection limit of 0.6 kPa is achieved at a noncontact distance of 10 *** when partly or completely immersed in water,the sensor effectively traces movement signals of human bodies underwater,demonstrating great advantages for non-inductive aquatic fitness training ***,due to the low acoustic impedance of piezoelectret film,speech recognition through gaseous medium is also *** further introduce application demonstrations of the developed film sensors to monitor exercise postures and physiological signals without direct contact between human body and the sensor,displaying great potential to be incorporated into future smart *** study commendably expands the application scope of piezoelectret materials,which will have profound implications for exploring novel intelligent human–machine interactions.

关键词： noncontact sensing piezoelectret multiple transmission media mechanical signal capture

Sulfonated poly(4-vinylpyridine) heteropolyacid salts:A reusable green solid catalyst for Mannich reaction

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Chinese Chemical Letters 2014年第4期25卷 575-578页

作者： Wen-You Li ying-Xiao Zong Jun-Ke Wang Yu-ying niu Department of Chemical Engineering Jiuquan Vocational and Technical College Key Laboratory of Hexi Corridor Resources Utilization of Gansu Universities College of Chemistry and Chemical EngineeringHexi University Gansu Engineering Laboratory of Applied Mycology Hexi University

Sulfonated poly（4-vinylpyridine） heteropolyacid salts acted as a heterogeneous catalyst to effectively catalyze the one-pot synthesis of β-amino carbonyl compounds via the Mannich reaction between aromatic aldehydes, aromatic ketone, and aromatic amines. In addition, the catalyst could be easily recovered by the filtration and reused six times without significant loss of catalytic activity.

关键词： Mannich reaction Heteropolyacid Poly(4-vinylpyridine) Heterogeneous catalyst

High Precision Prediction of Rolling Force Based on Fuzzy and Nerve Method for Cold Tandem Mill

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Journal of Iron and Steel Research(International) 2008年第2期15卷 23-27页

作者： JIA Chun-yu SHAN Xiu-ying niu Zhao-ping College of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

The rolling force model for cold tandem mill was put forward by using the Elman dynamic recursive network method,based on the actual measured ***,a good assumption is put forward,which brings a full universe of discourse self-adjusting factor fuzzy control,closed-loop adjusting,based on error feedback and expertise into a rolling force prediction model,to modify prediction outputs and improve prediction precision and *** simulated results indicate that the method is highly effective and the prediction precision is better than that of the traditional *** relative error is less than ±4%,so the prediction is high precise for the cold tandem mill.

关键词： Elman dynamic recursive network fuzzy control cold tandem mill rolling force prediction

Scalable high performance de-duplication backup via hash join

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第5期11卷 315-327页

作者： Tian-ming YANG Dan FENG Zhong-ying niu Ya-ping WAN Wuhan National Laboratory for Optoelectronics School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Apart from high space efficiency,other demanding requirements for enterprise de-duplication backup are high performance,high scalability,and availability for large-scale distributed *** main challenge is reducing the significant disk input/output(I/O) overhead as a result of constantly accessing the disk to identify duplicate *** inline de-duplication approaches mainly rely on duplicate locality to avoid disk bottleneck,thus suffering from degradation under poor duplicate locality *** paper presents Chunkfarm,a post-processing de-duplication backup system designed to improve capacity,throughput,and scalability for *** performs de-duplication backup using the hash join algorithm,which turns the notoriously random and small disk I/Os of fingerprint lookups and updates into large sequential disk I/Os,hence achieving high write throughput not influenced by workload *** importantly,by decentralizing fingerprint lookup and update,Chunkfarm supports a cluster of servers to perform de-duplication backup in parallel;it hence is conducive to distributed implementation and thus applicable to large-scale and distributed storage systems.

关键词： Backup system De-duplication Post-processing Fingerprint lookup Scalability

Analysis of Atmospheric Turbidity in Clear Skies at Wuhan,Central China

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Journal of Earth Science 2017年第4期28卷 729-738页

作者： Lunche Wang Yisen Chen ying niu German Ariel Salaza Wei Gong Department of Geography School of Earth SciencesChina University of GeosciencesWuhan 430074China Physics Department School of Exact SciencesSalta National UniversitySalta A4408FVYArgentina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

The Angstr6m turbidity coefficient （β） and Linke turbidity factor （TL） are used to study the atmospheric conditions in Wuhan, Central China, using measureβd direct solar radiation during 2010-2011 in this study. The results show that annual mean β values generally increase from 0.28 in the morning to 0.35 at noon, and then decrease to 0.1 in the late afternoon during the day; annual mean TL generally varies from 3 to 7 in Central China. Both turbidity coefficients have maximum values in spring and summer, while minimum values are observed in winter months. It also reveals that β values show preponderance （52.8%） between 0.15 and 0.35, 78.1% of TL values are between 3.3 and 7.7, which can be compared with other sites around the world. Relationship between turbidity coefficients and main me- teorological parameters （humidity, temperature and wind direction） have been further investigated, it is discovered that the local aerosol concentrations, dust events in northern China and Southwest Monsoon from the Indian Ocean influences the β values in the study area.

关键词： direct solar radiation AngstrOm turbidity coefficient Linke turbidity factor Central China.

Life cycle of Chetoneura shennonggongensis （Diptera： Keroplatidae： Keroplatinae） from Jiangxi Province, China

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Insect Science 2009年第4期16卷 351-359页

作者： Xue-Zhen Li Chang-ying niu Qiu-ying Huang Chao-Liang Lei David W. Stanley Key Laboratory of Utilization of Insect Resources and Sustainable Control of Pests Huazhong Agricultural University Wuhan China Agricultural Research Service Biological Control of Insects Research Laboratory Columbia USA

We report the first description of the biology of non-bioluminescent Keroplatidae from China. The life cycle of Chetoneura shennonggongensis is documented from laboratory culture and from field observations. The larval stage usually lasts 8-10 months. Large amounts of pupae are observed in late June, where they remain suspended horizontally or vertically from silk threads. The pupal suspending postures differ from other Keroplatidae species. Sexual differentiation is evident from the pupal stage. July is the peak time of adult emergence. Mating usually takes place immediately upon female emergence if adult males are available. The adult life span is short. Females live a maximum of 5 days and males 7 days. Egg development time varies from 20 30 days depending on environmental temperature. Larvae hang long sticky silk threads with a series of mucous droplets to capture prey. Some behaviors associated with snare construction and prey capture are also described.

关键词： Chetoneura shennonggongensis Chinese Keroplatidae life cycle

Design and Verification of Parallel Hip Exoskeleton Considering Output Torque Anisotropy

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Journal of Bionic Engineering 2024年第3期21卷 1305-1320页

作者： Jilong Xu Yunzhan niu Fucai Liu Engineering Research Center of the Ministry of Education for Intelligent Control System and Intelligent Equipment Yanshan UniversityQinhuangdao066004China Key Laboratory of Industrial Computer Control Engineering of Heibei Province Yanshan UniversityQinhuangdao066004China College of Mechanical Engineering Yanshan UniversityQinhuangdao066004China

In rehabilitation training,it is crucial to consider the compatibility between exoskeletons and human legs in ***,most exoskeletons today adopt an anthropomorphic serial structure,which results in rotational centers that are not precisely aligned with the center of the hip *** address this issue,we introduce a novel exoskeleton called the Parallel Hip Exoskeleton(PH-Exo)in this ***-Exo is meticulously designed based on the anisotropic law of output *** the friction of the drive components,a dynamic model of the human-machine complex is *** analysis demonstrates that PH-Exo not only exhibits outstanding torque performance but also achieves high controllability in both flexion/extension and adduction/abduction ***,a robust controller is designed to address model uncertainty,friction,and external *** experiments indicate that under the control of the robust controller,each motor achieves excellent tracking performance.

关键词： Hip exoskeleton Parallel mechanism Misalignment Anisotropy Output torque

ZnGa_(2)S_(4):an infrared nonlinear optical material with large second-harmonic generation response and wide band gap

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Rare Metals 2024年第1期43卷 395-401页

作者： Chen-Yang Zhang Xiao-Nan niu Yan-Feng Wei Shu-Xing Zhou Da-Qing Yang ying Wang Jian Wang Bing-Bing Zhang College of Chemistry and Materials Science Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationState Key Laboratory of New Pharmaceutical Preparations and ExcipientsHebei UniversityBaoding 071002China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Hubei Longzhong Laboratory Xiangyang 441000China Department of Chemistry and Biochemistry Wichita State UniversityKansas 67260USA

High-performance nonlinear optical(NLO)crystals are crucial devices to convert wavelength of solid-state *** play an indispensable role in the research of infrared NLO *** this work,ternary chalcogenide ZnGa_(2)S_(4) ... 详细信息

关键词： optical nonlinear harmonic