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Journal of Hydrodynamics 2021年第6期33卷 1162-1175页

作者： xiao-long Fu De-you Li Hong-jie Wang Yong-guang Cheng xian-zhu Wei State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Hydro-Power Equipment Harbin Institute of Large Electrical Machinery Harbin 150001China

A runaway transition after the pump power interruption and the simultaneous guide vane servomotor failure is one of the most dangerous and complex transitions for a pumped storage power system(PSPS).This paper analyzes the fluctuation behavior and mechanism of a PSPS during a runaway transition caused by the pump power *** transient cavitation flow in the PSPS is simulated by using a one-dimensional and three-dimensional coupling flow simulation method for the runaway ***,the effects of the transient fluctuation of the radial hydraulic thrust on the runner and transient pressures are analyzed using the short-time Fourier transform ***,the mechanisms are analyzed based on the analysis of the internal flow *** study suggests that the extreme fluctuation generally occurs near the critical transformation points between the two operation *** addition,the extreme fluctuation behavior is primarily related to the local backflow near the runner inlet and the unstable cavitation phenomena in the runner and the draft *** finding helps for optimizing the runner design to resolve the instability problems of a PSPS.

关键词： Pumped storage power system pump power-off runaway transient fluctuation behavior local backflow cavitation

Organic nitrogen components in soils from southeast China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第4期14卷 259-269页

作者： xian-you CHEN Liang-huan WU xiao-chuang CAO Yuan-hong zhu Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental and Resource SciencesZhejiang University Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource SciencesZhejiang University Department of Crop and Soil Sciences the Pennsylvania State UniversityUniversity ParkPennsylvania PA 16802USA

Objective:To investigate the amounts of extractable organic nitrogen(EON),and the relationships between EON and total extractable nitrogen(TEN),especially the amino acids(AAs) adsorbed by soils,and a series of other hydrolyzed soil nitrogen indices in typical land use soil types from southeast *** traditional agricultural planting conditions,the functions of EON,especially AAs in the rhizosphere and in bulk soil zones were also ***:Pot experiments were conducted using plants of pakchoi(Brassica chinensis L.) and rice(Oryza sativa L.).In the rhizosphere and bulk soil zone studies,organic nitrogen components were extracted with either distilled water,0.5 mol/L K2SO4or acid ***:K2SO4-EON constituted more than 30% of TEN pools.K2SO4-extractable AAs accounted for 25% of EON pools and nearly 10% of TEN pools in rhizosphere ***,both K2SO4-EON and extractable AAs contents had positive correlations with TEN ***:EON represented a major component of TEN pools in garden and paddy soils under traditional planting *** only a small proportion of the EON was present in the form of water-extractable and K2SO4-extractable AAs,the release of AAs from soil exchangeable sites might be an important source of organic nitrogen(N) for plant *** findings suggest that the content of most organic forms of N was significantly greater in rhizosphere than in bulk soil zone ***,it was also apparent that the TEN pool content was lower in rhizosphere than in bulk soil samples without added N.

关键词： Extractable organic nitrogen Amino acids Rhizosphere Bulk soil

Studies on LCST of poly (N-isopropylacrylamide-co-acrylic acid-co-N-diacetone acrylamide)

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Chinese Chemical Letters 2007年第1期18卷 79-80页

作者： Cai Hua Ni xiao Xia zhu Qing Lan Wang xian Yu Zeng School of Chemical and Material Engineering Southern Yangtze University Wuxi 214036 China Key Laboratory of Functional Polymer Materials School of Chemistry Polymer Institute Nankai University Tianjin 300073 China College of Material Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Linear copolymers from N-isopropylacrylamide （NIPA）, acrylic acid （AA） and diacetone acrylamide （DAA） have been prepared. The effect of composition, ionic strength and pH on their lower critical solution tempera... 详细信息

关键词： LCST Thermo-responsive N-Isopropylacrylamide N-Diacetone acrylamide

Determination of Kinetic Parameters and Metal Ions in Urea-Urease System Based on the Biochemical Reaction Heat Induced Laser Beam Deflection

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Chinese Chemical Letters 2000年第2期11卷 157-160页

作者： Hong Tao YAN xiao Yun zhu (Department of Chemistry, Northwest University, xian 710069) Department of Chemistry Northwest University Xian 710069 China

A new analytical method for the determination of urea-urease system based on biochemical reaction heat induced laser beam deflection is presented in this paper. With the method, the Michaelis constant (K-m) of urease and apparent inhibition constant (K-i) of some metal ion inhibitors were measured respectively. This method was also used for the quantitative determination of metal ions with satisfactory result.

关键词： urease kinetic parameter metal ions determination laser beam deflection

Metabolic pathway modulation by olanzapine:Multitarget approach for treating violent aggression in patients with schizophrenia

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World Journal of Psychiatry 2025年第1期15卷 37-53页

作者： Yan-Ning Song Shuang Xia Zhi Sun Yong-Chao Chen Lu Jiao Wen-Hua Wan Hong-Wei Zhang xiao Guo Hua Guo Shou-Feng Jia xiao-Xin Li Shi-xian Cao Li-Bin Fu Meng-Meng Liu Tian Zhou Lv-Feng Zhang Qing-Quan Jia Department of Pharmacy The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Department of Pharmacy The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Pharmacy Zhumadian First People's HospitalZhumadian 463000Henan ProvinceChina Scientific Education Section The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Department of Psychiatry The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Clinical Laboratory The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Publicity Division The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina

BACKGROUND The use of network pharmacology and blood metabolomics to study the patho-genesis of violent aggression in patients with schizophrenia and the related drug mechanisms of action provides new directions for reducing the risk of violent aggression and optimizing treatment *** To explore the metabolic regulatory mechanism of olanzapine in treating patients with schizophrenia with a moderate to high risk of violent *** Metabolomic technology was used to screen differentially abundant metabolites in patients with schizophrenia with a moderate to high risk of violent aggression before and after olanzapine treatment,and the related metabolic pathways were *** pharmacology was used to establish protein-protein interaction networks of the core targets of *** Ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were subsequently *** Compared with the healthy group,the patients with schizophrenia group presented significant changes in the levels of 24 metabolites related to the disruption of 9 metabolic pathways,among which the key pathways were the alanine,aspartate and glutamate metabolism and arginine biosynthesis *** treatment with olanzapine,the levels of 10 differentially abundant metabolites were significantly reversed in patients with *** effectively regulated six metabolic pathways,among which the key pathways were alanine,aspartate and glutamate metabolism and arginine biosynthesis *** core targets of olanzapine were involved in several key *** The metabolic pathways of alanine,aspartate,and glutamate metabolism and arginine biosynthesis are the key pathways involved in olanzapine treatment for aggressive schizophrenia.

关键词： Schizophrenia Violent aggression Olanzapine Metabolomics Network pharmacology

A Framework of Convergence Analysis of Mini-batch Stochastic Projected Gradient Methods

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Journal of the Operations Research Society of China 2023年第2期11卷 347-369页

作者： Jian Gu xian-Tao xiao School of Sciences Dalian Ocean UniversityDalian 116023China School of Mathematical Sciences Dalian University of TechnologyDalian 116023China

In this paper,we establish a unified framework to study the almost sure global convergence and the expected convergencerates of a class ofmini-batch stochastic(projected)gradient(SG)methods,including two popular types of SG:stepsize diminished SG and batch size increased *** also show that the standard variance uniformly bounded assumption,which is frequently used in the literature to investigate the convergence of SG,is actually not required when the gradient of the objective function is Lipschitz ***,we show that our framework can also be used for analyzing the convergence of a mini-batch stochastic extragradient method for stochastic variational inequality.

关键词： Stochastic projected gradient method Variance uniformly bounded Convergence analysis

A Model for Predicting Dynamic Cutting Forces in Sand Mould Milling with Orthogonal Cutting

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 95-105页

作者： Zhong-De Shan Fu-xian zhu State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science TechnologyBeijing 100083China Jiangsu University of Technology Changzhou 213001China

Cutting force is one of the research hotspots in direct sand mould milling because the cutting force directly a ects the machining quality and tool wear. Unlike metals, sand mould is a heterogeneous discrete deposition material. There is still a lack of theoretical research on the cutting force. In order to realize the prediction and control of the cut?ting force in the sand mould milling process, an analytical model of cutting force is proposed based on the unequal division shear zone model of orthogonal cutting. The deformation velocity relations of the chip within the orthogonal cutting shear zone are analyzed first. According to the flow behavior of granular, the unequal division shear zone model of sand mould is presented, in which the governing equations of shear strain rate, strain and velocity are estab?lished. The constitutive relationship of quasi?solid–liquid transition is introduced to build the 2D constitutive equation and deduce the cutting stress in the mould shear zone. According to the cutting geometric relations of up milling with straight cutting edge and the transformation relationship between cutting stress and cutting force, the dynamic cutting forces are predicted for di erent milling conditions. Compared with the experimental results, the predicted results show good agreement, indicating that the predictive model of cutting force in milling sand mould is validated. Therefore, the proposed model can provide the theoretical guidance for cutting force control in high e ciency mill?ing sand mould.

关键词： Green manufacture Cutting force Sand mould milling Orthogonal cutting Quasi?solid–liquid transition

A fast registration algorithm of rock point cloud based on spherical projection and feature extraction

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Frontiers of Computer Science 2019年第1期13卷 170-182页

作者： Yaru xian Jun xiao Ying WANG School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Point cloud registration is an essential step in the process of 3D *** this paper,a fast registration algorithm of rock mass point cloud is proposed based on the improved iterative closest point (ICP)*** our proposed algorithm,the point cloud data of single station scanner is transformed into digital images by spherical polar coordinates,then image features are extracted and edge points are removed,the features used in this algorithm is scale-invariant feature transform (SIFT).By analyzing the corresponding relationship between digital images and 3D points,the 3D feature points are extracted,from which we can search for the two-way correspondence as candidates. After the false matches are eliminated by the exhaustive search method based on random sampling,the transformation is computed via the Levenberg-Marquardt-Iterative Closest Point (LM-ICP)*** on real data of rock mass show that the proposed algorithm has the similar accuracy and better registration efficiency compared with the ICP algorithm and other algorithms.

关键词： rock point cloud registration LM-ICP spherical projection feature extraction

Universal composable secure protocol for EPC system

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The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 115-121,128页

作者： xiao Feng ZHOU Ya-jian ZHOU Jing-xian zhu Hong-liang NIU Xin-xin Information Security Center Beijing University of Posts and Telecommunications

As an important component of internet of things, electronic product code （EPC） system is widely used in many areas. However, the mass deployment of EPC system is frequently degraded by security and privacy problems. Therefore, the major researches focus on the design of a secure EPC system with high efficiency. This paper discusses the security requirements of EPC system and presents a universal composable （UC） model for EPC system, the ideal functionality of EPC system is also formally defined with the UC framework. Then a secure protocol for EPC system under UC framework is proposed and the analysis of security and performance of the proposed protocol is given, in comparison with other protocols, the results show that the proposed protocol is UC secure and can provide privacy protection, untraceability, authorized access, anonymity and concurrent security for EPC system. Furthermore, less computation and storage resource are required by the proposed protocol.

关键词： EPC system universal composable secure protocol privacy protection

Etching oxide overlayers of NiFe phosphide to facilitate surface reconstruction for oxygen evolution reaction

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Green Energy & Environment 2022年第3期7卷 365-371页

作者： Tehua Wang xian-zhu Fu Shuangyin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen518055China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China

Transition-metal phosphides have been of concern as efficient electrocatalysts for oxygen evolution reaction(OER)due to its high conductivity and earth-abundance ***,oxide overlayers formed on their surface by spontaneously atmospheric oxidation are usually neglected,thus confusing the establishment of structure–performance ***,we successfully etched the oxide overlayers of NiFe phosphide(NiFeP)by a dielectric barrier discharge(DBD)plasma technique,aiming to reveal the influence of the oxide overlayers on its electrocatalytic performance for *** is found that etching the oxide overlayers can accelerate the surface reconstruction process of NiFeP and facilitate the formation of metal hydroxides,which are key intermediate phases for ***,the etched NiFeP-DBD material shows remarkably enhanced OER activity with an overpotential of 265 mV at a current density of 10 mA cm^(-2).The finding of this work probably brings a significant impact to understand the structure–performance relationship of metal phosphide in electrooxidation reaction.

关键词： surface oxide evolution