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Modeling solidification structure evolution and microsegregation under pressure condition

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Journal of University of Science and Technology Beijing 2006年第6期13卷 516-522页

作者： qiang Li Qiaoyi guo Rongde Li School of Materials Science and Engineering Shenyang University of Technology Shenyang 110023 China Fundamental School Shenyang Ligong University Shenyang 110168 China

Solidification microstructure and microsegregation were simulated under a constant pressure condition using the cellular automaton method. First, a single dendrite evolution was simulated and compared under pressure condition and under normal condition, respectively. The solidification microstructure and microsegregation were then simulated. Through simulation, it may be concluded that if the growth direction of the dendrite is parallel to the pressure direction, dendrite growth will be hindered. On the other hand, pressure has no influence on the dendrite evolution. However, when two dendrites grow in close contact, solute enrichment occurs in the dendrites, which hinders the growth of the dendrites. In addition, the solute is preferentially enriched along the pressure direction.

关键词： dendrite microsegregation pressure condition modeling

Implicit finite difference method for fractional percolation equation with Dirichlet and fractional boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2016年第3期37卷 403-416页

作者： Boling guo qiang XU Zhe YIN Institute of Applied Physics and Computational Mathematics Beijing 100088 China School of Mathematical Sciences Shandong Normal University Jinan 250014 China

An implicit finite difference method is developed for a one-dimensional frac- tional percolation equation （FPE） with the Dirichlet and fractional boundary conditions. The stability and convergence are discussed for two special cases, i.e., a continued seep- age flow with a monotone percolation coefficient and a seepage flow with the fractional Neumann boundary condition. The accuracy and efficiency of the method are checked with two numerical examples.

关键词： fractional percolation equation (FPE) Riemann-Liouville derivative frac-tional boundary condition finite difference method stability and convergence Toeplitzmatrix

Potential Benefits of Green Tea in Prostate Cancer Prevention and Treatment:A Comprehensive Review

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Chinese Journal of Integrative Medicine 2024年第11期30卷 1045-1055页

作者： LIU Gui-hong YAO Ze-qin CHEN guo-qiang LI Ya-lang LIANG Bing Department of Urology Sanya Central Hospital(The Third People's Hospital of Hainan Province)Sanya CityHainan Province 572000China Department of Urology Yuzhou People's HospitalXuchang CityHenan Province 461670China

Prostate cancer is a prevalent and debilitating disease that necessitates effective prevention and treatment *** tea,a well-known beverage derived from the Camellia sinensis plant,contains bioactive compounds with potential health benefits,including catechins and *** comprehensive review aims to explore the potential benefits of green tea in prostate cancer prevention and treatment by examining existing *** tea possesses antioxidant,anti-inflammatory,and anti-carcinogenic properties attributed to its catechins,particularly epigallocatechin *** studies have reported an inverse association between green tea consumption and prostate cancer risk,with potential protection against aggressive forms of the *** studies demonstrate that green tea components inhibit tumor growth,induce apoptosis,and modulate signaling pathways critical to prostate cancer development and *** trials and human studies further support the potential benefits of green *** tea consumption has been found to be associated with a reduction in prostate-specific antigen levels,tumor markers,and played a potential role in slowing disease ***,challenges remain,including optimal dosage determination,formulation standardization,and conducting large-scale,long-term clinical *** review suggests future research should focus on combinatorial approaches with conventional therapies and personalized medicine strategies to identify patient subgroups most likely to benefit from green tea interventions.

关键词： green tea prostate cancer prevention treatment epigallocatechin gallate review

Ecological operation for Three Gorges Reservoir

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Water Science and Engineering 2011年第2期4卷 143-156页

作者： Wen-xian guo hong-xiang WANG Jian-xin XU Zi-qiang XIA North China University of Water Conservancy and Electric Power Zhengzhou 450011 P. R. China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai Univerxity Nanjing 210098 R R. China

The traditional operation of the Three Gorges Reservoir has mainly focused on water for flood control, power generation, navigation, water supply, and recreation, and given less attention to the negative impacts of reservoir operation on the river ecosystem. In order to reduce the negative influence of reservoir operation, ecological operation of the reservoir should be studied with a focus on maintaining a healthy river ecosystem. This study considered ecological operation targets, including maintaining the river environmental flow and protecting the spawning and reproduction of the Chinese sturgeon and four major Chinese carps. Using flow data from 1900 to 2006 at the Yichang gauging station as the control station data for the Yangtze River, the minimal and optimal river environmental flows were analyzed, and eco-hydrological targets for the Chinese sturgeon and four major Chinese carps in the Yangtze River were calculated. This paper proposes a reservoir ecological operation model, which comprehensively considers flood control, power generation, navigation, and the ecological environment. Three typical periods, wet, normal, and dry years, were selected, and the particle swarm optimization algorithm was used to analyze the model. The results show that ecological operation modes have different effects on the economic benefit of the hydropower station, and the reservoir ecological operation model can simulate the flood pulse for the requirements of spawning of the Chinese sturgeon and four major Chinese carps. According to the results, by adopting a suitable re-operation scheme, the hydropower benefit of the reservoir will not decrease dramatically while the ecological demand is met. The results provide a reference for designing reasonable operation schemes for the Three Gorges Reservoir.

关键词： ecological operation environmental flow Three Gorges Reservoir particle swarm optimization algorithm

Pulse-to-pulse periodic signal sorting features and feature extraction in radar emitter pulse sequences

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Journal of Systems Engineering and Electronics 2010年第3期21卷 382-389页

作者： qiang guo Zhenshen Qu Changhong Wang College of Information and Communication Engineering Harbin Engineering University Harbin 150001 R R. China Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin 150001 R R. China

A novel class of periodically changing features hidden in radar pulse sequence environment,named G features,is *** fractal theory and Hilbert-Huang transform,the features are extracted using changing characteristics of pulse parameters in radar emitter *** features can be applied in modern complex electronic warfare environment to address the issue of signal sorting when radar emitter pulse signal parameters severely or even completely *** results show that the proposed feature class and feature extraction method can discriminate periodically changing pulse sequence signal sorting features from radar pulse signal flow with complex variant features,therefore provide a new methodology for signal sorting.

关键词： signal sorting fractal geometry Hilbert-Huang transform(HHT) G feature extraction.

Controlled nano-cracking actuated by an in-plane voltage

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Science China(Information Sciences) 2021年第8期64卷 264-266页

作者： qiang LUO Zhe guo Shuai ZHANG Xiaofei YANG Xuecheng ZOU Jeongmin hong Long YOU School of Optical and Electronic Information Huazhong University of Science and Technology

Dear editor,Cracking has been generally regarded as an undesirable phenomenon to be avoided owing to their highly stochastic process and irreversibility. However, to induce nanocracks deliberately has been widely investigated because of their great potential for extended applications, such as strain sensors[1], flexible electronics [2] and nano-fabrication [3].

关键词： PMN Controlled nano-cracking actuated by an in-plane voltage

In situ anchoring in carbon matrix of Bi_(2)O_(2)CO_(3) as a high-performance anode material for Li-ion batteries

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Rare Metals 2024年第8期43卷 3634-3646页

作者： Pu-qiang He Jun guo Hui Huang Zhong-Cheng guo Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Research Center of Metallurgical Electrode Materials Engineering Technology Kunming 650106China Kunming Hendera Science and Technology Co. Ltd.Kunming 650106China

Bismuth-based anode materials have been regarded as promising Li-ion batteries due to their high theoretical ***,their low conductivity and associated volume expansion inhabited their *** this work,Bi_(2)O_(2)CO_(3)@C composites were successfully synthesized by in situ anchoring of flower-like Bi_(2)O_(2)CO_(3) nanosheets on a carbon-based substrate via *** unique composited structure of Bi_2O_(2)-CO_(3)@C leads to a stable specific capacity of 547 mAh·g^(-1)after 100 cycles at a current density of 0.1 A·g^(-1).Notably,it demonstrates excellent rate capability with a specific capacity of 210 mAh·g^(-1)at 5 A·g^(-1).After 550 cycles at a current density of 0.5 A·g^(-1),a high reversible capacity of nearly 400 mAh·g^(-1)was ***,in situ X-ray diffraction measurements clearly demonstrate the conversion between Bi and Li_(3)Bi during alloying/dealloying,confirming the good electrochemical reversibility of the materials for Li *** reaction kinetics of Bi_(2)O_(2)CO_(3)@C were further investigated using galvanostatic intermittent titration ***,Bi_2O_(2)-CO_(3)@C exhibited excellent long-term stability,maintaining its high reversible capacity for over 200 cycles at a current density of 0.5 A·g^(-1)in a full cell configuration using Li_(1.20)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2) as the cathode *** result further underscores its promising potential for lithium-ion *** work may provide inspiration for the design of alloy-type negative electrode materials for high-performance rechargeable batteries.

关键词： Bi_(2)O_(2)CO_(3) Composite materials Anode materials Full batteries

Polymorphisms in HIF-1a gene are not associated with diabetic retinopathy in China

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World Journal of Diabetes 2021年第8期12卷 1304-1311页

作者： Yue-hong Liu Chang guo Yi-Qiong Sun qiang Li Department of Endocrinology Hainan Cancer HospitalHaikou 570312Hainan ProvinceChina Department of Endocrinology Shenzhen University General HospitalShenzhen 518055Guangdong ProvinceChina

BACKGROUND It has been reported that vascular endothelial growth factor(VEGF)is a susceptibility gene for both type 2 diabetes mellitus(T2DM)and diabetic retinopathy(DR).In response to hypoxia,VEGF mRNA levels are increased,which is mainly mediated by the binding of hypoxia-inducible factor-1(HIF-1)and hypoxia response element upstream of the transcriptional start site of ***,HIF-1a is supposed to be involved in pathology of *** To investigate whether the polymorphisms in HIF-1a gene are associated with *** Two hundred and ninety-nine type 2 diabetic patients(128 males and 171 females)and 144 healthy volunteers were *** age was 56.04±21.05 *** to the results of fundus fluorescein angiography and examination of ophthalmoscopy,patients were divided into two groups,DNR group(diabetes without retinopathy)and DR group(diabetes with retinopathy).There are 150 cases in DNR group and 149 cases in DR *** single nucleotide polymorphisms(SNP)of the HIF-1a gene were tested using matrix-assisted laser desorption/Ionization time of flight mass *** frequency of genotypes and alleles,and odds ratio were *** The mean age of the cases with diabetes was 55.84±3.66 years,the mean age of the cases with DR was 55.97±4.66 years and that of controls was 56.32±4.70 *** variations were found in 76 ***11549465 is the change of C-T base,rs11549467 is the change of G-A *** rs11549467 G/A genotype was 5.33%in diabetes and 6.04%in DR patients,*** rs11549465 C/T genotype was 10%and 12.75%in patients with diabetes and *** rs11549467 A allele frequencies and rs11549465 T frequencies was similar to that of *** SNP linkage disequilibrium analysis indicated that rs11549467 was in linkage disequilibrium with *** association analysis denoted that the haplotype association exhibited similar distribution in the patients compared to the normal *** This s

关键词： Diabetic retinopathy Single nucleotide polymorphisms HIF1a Vascular endothelial growth factor Diabetes Mutation

Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

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Journal of Integrative Agriculture 2024年第1期23卷 122-140页

作者： Jingui Wei qiang Chai Wen Yin hong Fan Yao guo Falong Hu Zhilong Fan QimingWang State Key Laboratory of Aridland Crop Science Lanzhou 730070China College of Agronomy Gansu Agricultural UniversityLanzhou 730070China College of Life Sciences Northwest Normal UniversityLanzhou 730070China

The development of modern agriculture requires the reduction of water and chemical N fertilizer *** the planting density can maintain higher yields,but also consumes more of these restrictive ***,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains *** study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to *** treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N *** water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme *** with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improv

关键词： water and N reduction plant density maize grain yield N uptake compensation effect