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Protective Effects of Phellodendron Species on Bone Health: A Novel Perspective on Their Potentials in Treating Osteoporosis and Osteoarthritis

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Chinese Journal of Integrative Medicine 2024年第4期30卷 379-384页

作者： XIN li TAN Guo-yao zhang qiang zhang Qun Good Clinical Practice Development Guangdong Provincial Key Laboratory of Bone and Joint Degeneration DiseasesThe Third Affiliated Hospital of Southern Medical UniversityGuangzhou(510630)China Department of Pharmacy Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou(510120)China

Phellodendron(PN)species,traditionally used in Chinese medicine for centuries,hold promise as a potential treatment for osteoporosis(OP)and osteoarthritis(OA)due to their bioactive *** bioactive compounds,including berberine and palmatine,exhibit anti-inflammatory,antioxidant,and bone-protective properties,contributing to their potential therapeutic benefits in promoting bone health and preventing bone ***,challenges such as the need for standardized preparation and dosing,limited clinical studies,and potential interactions with other medications hinder their clinical ***,the rich history of PN species in Chinese medicine provides a promising foundation for future investigation into their potential as alternative treatments for OP and *** research is needed to fully understand the underlying mechanisms of action and explore the clinical implications of PN for bone health.

关键词： Phellodendron species bone health osteoporosis osteoarthritis review

Performance of an electron linear accelerator for the first photoneutron source in China

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Nuclear Science and Techniques 2019年第4期30卷 1-7页

作者： Xuan li Jun-qiang zhang Guo-qiang lin Wen-Cheng Fang qiang Gu Meng zhang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai Synchrotron Radiation Facility Chinese Academy of Sciences University of Chinese Academy of Sciences

A compact 15.0-MeV, 1.5-kW electron linear accelerator(liNAC) was successfully constructed to provide an electron beam for the first photoneutron source at the Shanghai Institute of Applied Physics, Shanghai,China. This liNAC consists of five main parts: a thermal cathode grid-controlled electron gun, a pre-buncher, a variable-phase-velocity buncher, a light-speed accelerating structure, and a high-power transportation beamline. A digital feedforward radio frequency compensator is adopted to reduce the energy spread caused by the transient beam loading effect. Furthermore, a real-time electron gun emission feedback algorithm is used to keep the beam stable. After months of efforts, all the beam parameters successfully met the requirements of the facility. In this paper, the beam commissioning process and performance of the liNAC are presented.

关键词： Electron linear accelerator High-power transportation beamline Digital feedforward radio frequency compensation Real-time electron gun emission feedback algorithm Transmission efficiency

Time-of-use Pricing Model Considering Wind Power Uncertainty

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1039-1047页

作者： Gang zhang Ye Yan Kaoshe zhang Pingli li Meng li qiang He Hailiang Chao State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China Institute of Electrical Engineering Xi'an University of TechnologyXi'an 710048China Shaanxi Gas Group New Energy Development Co. LtdXi'an 710016China

Large-scale new energy pressures on the grids bring challenges to power system's security and *** order to optimize the user's electricity consumption behavior and ease pressure,which is caused by new energy on the grid,this paper proposes a time-of-use price model that takes wind power uncertainty into ***,the interval prediction method is used to predict wind *** typical wind power scenes are selected by random sampling and bisecting the K-means *** this basis,integer programming is used to divide the peak-valley period of the multi-scenes ***,under the condition of many factors such as user response based on consumer psychology,user electricity charge and power consumption,this paper takes the peak-valley difference of equivalent net load and the user dissatisfaction degree as the goal,and using the NSGA-II multi-objective optimization algorithm,evaluates the Pareto solution set to obtain the optimal *** order to test the validity of the model proposed in this paper,we apply it to an industrial user and wind farms in Yan'an city,*** results show that the model can effectively ensure the user's electrical comfort while achieving the role of peak shaving and valley flling.

关键词： Bisecting K-means algorithm interval prediction integer programming NSGA-II algorithm peakvalley difference time-of-use price user dissatisfaction wind power uncertainty

Optimization method for solving bang-bang and singular control problems

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控制理论与应用（英文版） 2012年第4期10卷 559-564页

作者： Shurong li Ruiyan ZHAO qiang zhang College of Information and Control Engineering China University of Petroleum

In this paper we study optimal control problems with the control variable appearing linearly. A novel method for optimization with respect to the switching times of controls containing both bang-bang and singular arcs is presented. This method transforms the control problem into a finite-dimensional optimization problem by reformulating the control problem as a multi-stage optimization problem. The optimal control problem is partitioned as several stages, with each stage corresponding to a particular control arc. A control vector parameterization approach is applied to convert the control problem to a static nonlinear programming （NLP） problem. The control profiles and stage lengths act as decision variables. Based on the Pontryagin maximal principle, a multi-stage adjoint system is constructed to calculate the gradients required by the NLP solvers. Two examples are studied to demonstrate the effectiveness of this strategy.

关键词： Bang-bang control Singular control Multi-stage problem Nonlinear programming problem

Kinematics Analysis and Optimization of the Fast Shearing-extrusion Joining Mechanism for Solid-state Metal

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1123-1131页

作者： zhang Shuangjie YAO Yunfeng li lingchong WANG lijuan li Junxia li qiang School of Materials Science and Engineering Hebei University of Science and Technology Key Laboratory of Material Near-net Forming Technology of Hebei Province School of Mechanical Engineering Yanshan University

Dynamical Joining of the solid-state metal is the key technology to realize endless hot rolling. The heating and laser welding method both require long joining time. Based on super deformation method, a 7-bar and 2-slider mechanism was developed in Japan, and the joining time is less than 0.5 s, however the length of each bar are not reported and this mechanism is complex. A relatively simple 6-bar and 1-slider mechanism is put forward, which can realize the shearing and extrusion motion of the top and bottom blades with a speed approximately equal to the speed of the metal plates. In order to study the kinematics property of the double blades, based on complex vector method, the multi-rigid-body model is built, and the displacement and speed functions of the double blades, the joining time and joining thickness are deduced, the kinematics analysis shows that the initial parameters can＇t satisfy the joining process. Hence, optimization of this mechanism is employed using genetic algorithm（GA） and the optimization parameters of this mechanism are obtained, the kinematics analysis show that the joining time is less than 0.1 s, the joining thickness is more than 80% of the thickness of the solid-state metal, and the horizontal speeds of the blades are improved. A new mechanism is provided for the joining of the solid-state metal and a foundation is laid for the design of the device.

关键词： endless rolling solid-state metal dynamical joining mechanism kinematic optimization genetic algorithm

Prey life stages modulate effects of predation stress on prey lifespan,development,and reproduction in mites

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Insect Science 2023年第3期30卷 844-856页

作者： Xiaoying Weil Guangyun li Zhi-qiang zhang School of Biological Sciences The University of AucklandAucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina Manaaki Whenua-Landcare Research AucklandNewZealand

The non-consumptive effects of predator-induced stress can influence a variety of life-history *** previous studies focused only on short-term effects such as development and reproductive *** studies have showed that long-term predation stress(given during the whole life of the prey)and short-term predation stress(provided during the immature stage of the prey)could generate completely opposite results:the former could decrease lifespan,whereas the later could increase ***,it is still unclear whether the advantage is because of the short duration of exposure or the early stage of life during which exposure was ***,in this study,the prey(Tyrophagus putrescentiae)was exposed to predation stress from the predator(Neoseiulus cucumeris)during different life stages(larva,protonymph,tritonymph,first 5 d of oviposition,the full lifespan or none of the above).The results showed that the predation stress supplied during larval and protonymphal stage delayed development,reduced fecundity and prolonged lifespan of the prey,while the stress given during tritonymphal stage only reduced lifespan slightly and the stress given during the first 5 d of oviposition did not change lifespan but reduced *** study indicated that the effects of predation stress are dependent on prey life stage and the predation stress experienced in the early life stages is important to lifespan modulation.

关键词： early life experience lifespan non-consumptive effects predation stress tyrophagus

Impact of livelihood diversification of rural households on their ecological footprint in agro-pastoral areas of northern China

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Journal of Arid Land 2015年第5期7卷 653-664页

作者： HAO Haiguang zhang Jiping li Xiubin zhang Huiyuan zhang qiang Chinese Research Academy of Environmental Sciences Beijing Municipal Research Institute of Environmental Protection Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance （ANOVA） and correlation analysis methods. In 2011, the total ecological footprint of consumption （EFC） was 0.665 g hm2, and the total ecological footprint of production （EFP） was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption （EFAC） accounted for a large proportion of the EFC, and the ecological footprint of grassland production （EFGP） occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption （EFGC） and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households （FTFHs） had the highest EFP, ecological footprint of arable land production （EFAP）, EFGP and EFGC, followed by the part-time farming households （PTFHs） and non-farming households （NFHs）, which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participati

关键词： ecological footprint livelihood diversification livestock rearing non-farming employment rural households agro-pastoral area

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International Journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1450-1456页

作者： Ying Yan Guo-qiang zhang li-jia Chen Xiao-wu li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

To explore the specimen size effect of mechanical behavior of ultrafine-grained(UFG)materials with different structures,UFG Al sheets processed by equal channel angular pressing(ECAP)were selected as target materials and the dependency of tensile behavior on sheet thickness(t)was systematically *** strength and ductility of ECAPed UFG Al sheets were improved synchronously as t increased from 0.2 to 0.7 mm,and then no apparent change occurred when t reached to 0.7 and 1.0 *** corresponding microstructure evolved from dislocation networks in equiaxed grains into the walls and subgrains and finally into the dominated cells in elongated grains or ***,dense shear lines(SLs)and shear bands(SBs)were clearly observed and microvoids and cracks were initiated along SBs with the increase of *** observations indicated that the plastic deformation of UFG Al sheets was jointly controlled by shear banding,dislocation sliding,and grain-boundary ***,the propagation of SBs became difficult as t ***,the obtained results were discussed and compared with those of annealed UFG Al and UFG Cu.

关键词： ultrafine-grained pure Al specimen size effect strength ductility

Gas–liquid mass transfer and flow phenomena in the Peirce–Smith converter: a water model study

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 37-44页

作者： Xing Zhao Hong-liang Zhao li-feng zhang li-qiang Yang Institute of Process Engineering Chinese Academy of ScienceBeijing 100190China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Green Recycling and Extraction of Metal Beijing 100083China Chambishi Copper Smelter Ltd. Beijing Representative OfficeBeijing 100029China

A water model with a geometric similarity ratio of 1：5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a NaOH solution bath. The flow field, volumetric mass transfer coefficient per unit volume （Ak/V; where A is the contact area between phases, V is the volume, and k is the mass transfer coeffi- cient）, and gas utilization ratio （t/） were then measured at different gas flow rates and blow angles. The results showed that the flow field could be divided into five regions, i.e., injection, strong loop, weak loop, splashing, and dead zone. Whereas the Ak/V of the bath increased and then decreased with increasing gas flow rate, and n steadily increased. When the converter was rotated clockwise, both Ak/F and t/increased. However, the flow condition deteriorated when the gas flow rate and blow angle were drastically increased. Therefore, these para- meters must be controlled to optimal conditions. In the proposed model, the optimal gas flow rate and blow angle were 7.5 m3.h-1 and 10°, respectively.

关键词： Peirce-Smith converter water model mass transfer flow phenomena volumetric mass transfer coefficient