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Influence of topography,soil properties and plant community on the biomass of Abies georgei *** seedlings in Southeast Tibet

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Journal of Mountain Science 2022年第9期19卷 2664-2677页

作者： ZHANG Xin-sheng ZHOU Chen-ni LU jie Institute of Tibet Plateau Ecology Tibet Agricultural&Animal Husbandry UniversityNyingchi 860000China Key Laboratory of Forest Ecology in Tibet Plateau Tibet Agricultural&Animal Husbandry UniversityMinistry of EducationNyingchi 860000China Linzhi National Forest Ecosystem Observation&Research Station of Tibet Nyingchi 860000China Key Laboratory of Alpine Vegetation Ecological Security in Tibet Nyingchi 86000China

Biomass of seedlings at different developing stages of growth is important information for studying the response of species to site *** objectives of this study was to explore the distribution characteristics of AGB(above-ground biomass)and BGB(below-ground biomass)of Abies georgei *** seedlings of different ages,and investigate the effects of topography(slope aspect,altitude),plant community characteristics(crown density,species diversity,etc.),and soil properties(soil physical and chemical properties)on the biomass and its *** in five age classes(1–2,3–4,5–6,7–8,and 9–10 years old)were collected by full excavation from 6 elevations(3800 m,3900 m,4000 m,4100 m,4200 m,4300 m)on the north and south slopes of Sejila Mountain in Tibet.15seedlings of each age class were investigated at one *** individual effects of seedling age(SA)and the interaction effects of SA,slope aspect(SL),and elevation(EG),namely,SL×EG,SL×SA,EG×SA,and SL×EG×SA,had significant effects on the AGB of the seedlings(pnificantly affected by SA(p<0.001).The AGB and BGB of the seedlings showed a binomial growth trend with the increase in seedling age,and had an allometric relationship at different elevations,α(allometric exponential)varied from 0.913 to 1.046 in the northern slope,and from 1.004 to 1.268 in the southern *** biomass of seedlings on the northern slope was remarkably affected by stand factors,with a contribution rate of 47.8%,whereas that on the southern slope was considerably affected by soil factors with a contribution rate of 53.2%.The results showed that age was the most important factor affecting seedling *** allometric pattern of seedling biomass was relatively stable,but in a highaltitude habitat,*** *** seedlings increased the input of *** seedling biomass allocation and its influencing factors is useful for evaluating plants’ability to acquire resources and surviv

关键词： Biomass allocation Allometric relationship Stand characteristic Soil factors Abies georgei var.smithii seedlings Sejila Mountain,Tibet

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A nanoplatform self-assembled by coordination delivers siRNA for lung cancer therapy

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Rare Metals 2023年第5期42卷 1483-1493页

作者： Zi-Yao Wang jie Mei Dong-Qi ni Sheng-Mei Li Jin-Min Ye Shi-Lin Li Ya-Ling Wang ying Liu CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety and CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of ChinaBeijing100190China University of Chinese Academy of Sciences Beijing100049China GBA National Institute for Nanotechnology Innovation Guangzhou510700China

The high incidence and mortality of lung cancer have present threaten in front of people all over the *** in clinical trials find that mutations of some genes influence progress of lung cancer directly or indirectly,therefore,some kinds of molecular inhibitors benefit patients in clinical therapy,which helpfully prolong survival time of patients and show great potential in lung cancer *** is a kind of nucleic acid molecules which can silence targeted gene translation through binding to mRNA completely to cure *** delivery of siRNA for cancer therapy mostly can be classified into loading through electrostatic interaction,physical surrounding,and chemically *** delivering siRNA by coordination has not been *** study unprecedently utilizes the coordination between siRNA and Fe^(2+)to form a self-assembly structure in which doxorobicin(DOX) and human serum albumin(HSA) were used to stabilize the whole nanoplatform followed polyethylenimine(PEI) *** the heat incubation strategy,highly loading efficiency for siRNA and DOX was *** nanoplatform with stability and sustain release of drugs exhibited good lysosome escape,gene silencing effect and cytotoxicity which provided new horizon for co-deli very of siRNA and other molecular or protein drugs.

关键词： Lung cancer siRNA Coordination Nanoparticles Drug delivery

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Task offloading mechanism based on federated reinforcement learning in mobile edge computing

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Digital Communications and Networks 2023年第2期9卷 492-504页

作者： jie Li Zhiping Yang Xingwei Wang Yichao Xia Shijian ni School of Computer Science and Engineering Northeastern UniversityShenyang110000China

With the arrival of 5G,latency-sensitive applications are becoming increasingly *** Edge Computing(MEC)technology has the characteristics of high bandwidth,low latency and low energy consumption,and has attracted much attention among *** improve the Quality of Service(QoS),this study focuses on computation offloading in *** consider the QoS from the perspective of computational cost,dimensional disaster,user privacy and catastrophic forgetting of new *** QoS model is established based on the delay and energy consumption and is based on DDQN and a Federated Learning(FL)adaptive task offloading algorithm in *** proposed algorithm combines the QoS model and deep reinforcement learning algorithm to obtain an optimal offloading policy according to the local link and node state information in the channel coherence time to address the problem of time-varying transmission channels and reduce the computing energy consumption and task processing *** solve the problems of privacy and catastrophic forgetting,we use FL to make distributed use of multiple users’data to obtain the decision model,protect data privacy and improve the model *** the process of FL iteration,the communication delay of individual devices is too large,which affects the overall delay ***,we adopt a communication delay optimization algorithm based on the unary outlier detection mechanism to reduce the communication delay of *** simulation results indicate that compared with existing schemes,the proposed method significantly reduces the computation cost on a device and improves the QoS when handling complex tasks.

关键词： Mobile edge computing Task offloading QoS Deep reinforcement learning Federated learning

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Influence of NO2^- on the Microscopic Structure and Physical Properties of the Binary nitrate Salts: a Molecular Dynamics Simulation Study

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Journal of Thermal Science 2020年第2期29卷 464-476页

作者： ni Haiou WU jie SUN Ze LU Guimin YU Jianguo Engineering Research Center of Resources Process Engineering Ministry of EducationSchool of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry and Chemical Engineering Qinghai Nationalities UniversityXi'ning 810007China

Molecular dynamics simulation method was used to study the influence of NO2^- on both the structure and properties of the binary nitrate salts(60 wt.% NaNO3 + 40 wt.% KNO3). The density and viscosity of the mixtures were experimentally measured and the simulation results met well with the experimental ones. The simulation results showed that, with the addition of NO2^-, the ionic clusters tended to loose and the mobilities of all the ions tended to increase. The density, viscosity, and heat capacity decreased while the thermal conductivity increased with the increase of NO2^- concentration. The correlation between the microscopic structure and physical properties of the mixtures were discussed and revealed.

关键词： molten salt molecular dynamics simulation nitrate nitrite

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Sperm origins and concentration do not impact the clinical outcomes in intracytoplasmic sperm injection cycles

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Asian Journal of Andrology 2018年第5期20卷 454-458页

作者： Cen Yang Ze-Hong Zhou Dan-ni Zheng Xiao-Fei XU Jin Huang ying Lian jie Qiao Center for Reproductive Medicine Department of Obstetrics and Gynecology Peking University Third Hospital Beijing 100191 China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproduction Technology Beijing 100191 China Key Laboratory of Assisted Reproduction Ministry Of Education Beijing 100191 China

In the present study, we evaluated the impact of sperm origins and concentration on the clinical outcomes of intracytoplasmic sperm injection （ICSI） cycles. A total of 1201 IC51 cycles were retrospectively analyzed for male azoospermia or oligozoospermia between January 2015 and December 2015 in the Peking University Third Hospital. Patients were divided into three groups （Group 1 vs Group 2/3; surgically extracted sperm vs ejaculated sperms）： Group 1 included 343 ICSI cycles and Group 2 analyzed 388 cycles on semen with sperm concentration 〈5 × 10^6 m1-1 （severe oligozoospermia group）. Group 3 included 470 cycles with sperm concentration between 5×10^6 m1-1 and 15 × 10^6 m1-1 （mild oligozoospermia group）. Fertilization rates, clinical pregnancy rates, and live birth rates were analyzed and compared among groups of different semen origins and concentrations on the oocyte retrieval day. Group 2 showed a lower fertilization rate than Group 3 （62.9%± 21.6% vs 66.8% ± 22.1%, P 〈 0.05）. There were no statistically significant differences in clinical pregnancy rate per transfer （51.3%, 46.7%, and 50.0%, respectively）, live birth rate per transfer （44.4%, 40.9%, and 41.4%, respectively）, accumulative live birth rate （58.3%, 51.0%, and 52.1%, respectively）, twin birth rate （18.4%, 10.6%, and 12.6%, respectively）, and birth defects rate （0, 0.3%, and 0.2%, respectively） among three groups. The results of this study indicated that sperm origins and concentration do not imDact the clinical outcomes in ICSI cycles.

关键词： azoospermia clinical outcomes intracytoplasmic sperm injection oligozoospermia sperm concentration

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Shape of slab solidification end under non-uniform cooling and its influence on the central segregation with mechanical soft reduction

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1788-1798页

作者： jie Li Yan-hui Sun Hang-hang An Pei-yuan ni Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgy Northeastern UniversityShenyang 110819China Hesteel Group Technology Research Institute Shijiazhuang 050000China

In order to study the effect of continuous casting process parameters on the shape of slab solidification end under non-uniform cooling,a solidification model of a continuous-cast slab with non-uniform cooling condition was established with ProCAST *** model was verified by the results of nail shooting tests and the infrared temperature measurement *** characteristic parameters were defined to evaluate the uniformity of the shape of slab solidification *** results showed that the nonuniformity at the beginning and end of solidification,the solidification end length,and the solidification unevenness increased with the rise of casting *** each 10°C increase of superheat,the solidification unevenness increased by about ***,the effect of superheat on the solidification end length can be *** secondary cooling strength showed minimal effect on the nonuniformity at the beginning and end of *** the increase in secondary cooling intensity,the solidification end length decreased,but the solidification unevenness *** addition,the central segregation of the slab produced with and without the mechanical soft reduction(MSR)process was *** transverse flow of molten steel with low solid fraction influenced the central segregation morphology under MSR.

关键词： continuous casting heat transfer model nail shooting shape of solidification end central segregation

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Intrinsic transverse relaxation mechanisms of polarized alkali atoms enclosed in radio-frequency magnetometer cell

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Chinese Physics B 2019年第9期28卷 385-390页

作者： Yang-ying Fu jie Yuan College of Advanced Interdisciplinary Studies National University of Defense Technology

The intrinsic transverse relaxation mechanisms of polarized alkali atoms enclosed in the radio-frequency magnetometer cell are *** intrinsic transverse relaxation rate of cesium atoms as a function of cell temperature is *** absorption of alkali atoms by the glass wall and the reservoir effect are the main error factors which contribute to the disagreements between theory and experiments.A modified relaxation model is presented, in which both the absorption of alkali atoms by the glass wall and the reservoir effect are *** study provides a more accurate description of the intrinsic transverse relaxation mechanisms of polarized alkali atoms, and enlightens the optimization of the cell design.

关键词： intrinsic transverse relaxation modified relaxation model absorption of alkali atoms reservoir effect

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Generalized Toda Mechanics Associated with Loop Algebra L（Br）

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Communications in Theoretical Physics 2005年第3期43卷 407-412页

作者： YANGZhan-ying ZHAOLiu SHIKang-jie DepartmentofPhysics NorthwestUniversityXi＇an710069China DepartmentofPhysics NankaiUniversityTianjin300071China DepartmentofPhysics NorthwestUniversityXi＇an710069China

A class of generalization of Toda mechanics with long range interactions isconstructed in this paper. These systems are associated with the loop algebras L(B_r) in the sensethat their Lax matrices can be realized in terms of the c = 0 representations of the affine Liealgebras B_r~((1)) . We adopt a pair of ordered integers (m, n) to describe the Toda mechanicssystem when we present the equations of motion and the Hamiltonian structure. We also extract theclassical r matrix which satisfy the classical Yang-Baxter relation. Such generalizations willbecome systems with noncommutative variables in the quantum case.

关键词： toda many-body mechanics system poisson bracket r matrix

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Effects of coal molecular structure and pore morphology on methane adsorption and accumulation mechanism

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Frontiers of Earth Science 2023年第1期17卷 262-272页

作者： Jingshuo ZHANG Xiaoming ni ying HAN Junfeng LIN School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China

The adsorption,diffusion,and aggregation of methane from coal are often studied based on slit or carbon nanotube models and isothermal adsorption and thermodynamics ***,the pore morphology of the slit model involves a single slit,and the carbon nanotube model does not consider the molecular structure of *** difference of the adsorption capacity of coal to methane was determined without considering the external environmental conditions by the molecular structure and pore morphology of *** study of methane adsorption by coal under single condition cannot reveal its *** view of this,elemental analysis,FTIR spectrum,XPS electron energy spectrum,13C NMR,and isothermal adsorption tests were conducted on the semi-anthracite of Changping mine and the anthracite of Sihe Mine in Shanxi Province,*** grand canonical Monte Carlo(GCMC)and molecular dynamics simulation method was used to establish the coal molecular structure *** comparing the results with the experimental test results,the accuracy and practicability of the molecular structure model are *** on the adsorption potential energy theory and aggregation model,the adsorption force of methane on aromatic ring structure,pyrrole nitrogen structure,aliphatic structure,and oxygen-containing functional group was *** relationship between pore morphology,methane aggregation morphology,and coal molecular structure was *** results show that the adsorption force of coal molecular structure on methane is as follows:aromatic ring structure(1.96 kcal/mol)>pyridine nitrogen(1.41 kcal/mol)>pyrrorole nitrogen(1.05 kcal/mol)>aliphatic structure(0.29 kcal/mol)>oxygen-containing functional group(0.20 kcal/mol).In the long and narrow regular pores of semi-anthracite and anthracite,methane aggregates in clusters at turns and aperture changes,and the adsorption and aggregation positions are mainly determined by the aromatic ring structure,the positions of pyrrole nitrog

关键词： Grand Canonical Monte Carlo pore morphology methane adsorption molecular structure of coal

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A New Class of Weights Adapted to Rough Singular Integrals and Marcinkiewicz Integrals

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Acta Mathematica Sinica,English Series 2009年第8期25卷 1275-1288页

作者： Chun jie ZHANG ying YOU School of Science Hangzhou Dianzi University Hangzhou 310018 P. R. China TDepartment of Mathematics Hanghzou Normal University Hangzhou 310036 P. R. China

In this paper, we introduce a new class of weights Ap （Rn） which retains many fine properties of the classical Muchenhoupt weights Ap （Rn）. While Ap （Rn） is too big a class to obtain the weighted norm inequalities for rough singular integrals and Marcinkiewicz integrals, our new class Ap （Rn） adapts well to these rough operators. As applications, we improve some known weighted estimates.

关键词： weighted estimates singular integral Marcinkiewicz integral

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