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Sensitivity and areal differentiation of vegetation responses to hydrothermal dynamics on the northern and southern slopes of the Qinling Mountains in Shaanxi province

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Journal of Geographical Sciences 2021年第6期31卷 785-801页

作者： QI Guizeng BAI hongying ZHAO Ting meng Qing ZHANG Shanhong Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127China Institute of Qinling Mountains Northwest UniversityXi'an 710127China College of Urban and Environmental Science Northwest UniversityXi'an 710127China

The Qinling Mountains,located at the junction of warm temperate and subtropical zones,serve as the boundary between north and south *** the sensitivity of the response of vegetation there to hydrothermal dynamics elucidates the dynamics and mechanisms of the main vegetation types in the context of changes in temperature and *** should be attached to changes in vegetation in different climate *** reveal the sensitivity and areal differentiation of vegetation responses to hydrothermal dynamics,the spatio-temporal variation characteristics of the normalized vegetation index(NDVI)and the standardized precipitation evapotranspiration index(SPEI)on the northern and southern slopes of the Qinling Mountains from 2000 to 2018 are explored using the meteorological data of 32 meteorological stations and the MODIS NDVI *** results show that:1)The overall vegetation coverage of the Qinling Mountains improved significantly from 2000 to *** NDVI rise rate and area ratio on the southern slope were higher than those on the northern slope,and the vegetation on the southern slope improved more than that on the northern *** Qinling Mountains showed an insignificant humidification *** humidification rate and humidification area of the northern slope were greater than those on the southern slope.2)Vegetation on the northern slope of the Qinling Mountains was more sensitive to hydrothermal dynamics than that on the southern *** was most sensitive to hydrothermal dynamics from March to June on the northern slope,and from March to May(spring)on the southern *** vegetation on the northern and southern slopes was mainly affected by hydrothermal dynamics on a scale of 3–7 months,responding weakly to hydrothermal dynamics on a scale of 11–12 months.3)Some 90.34%of NDVI and SPEI was positively correlated in the Qinling *** humidification in most parts of the study area promoted the growth of vegetation all

关键词： Qinling Mountains in Shaanxi province NDVI SPEI sensitivity spatial difference

Lactiplantibacillus plantarum FRT4 attenuates high-energy low-protein dietinduced fatty liver hemorrhage syndrome in laying hens through regulating gut-liver axis

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1292-1311页

作者： Daojie Li hongying Cai Guohua Liu Yunsheng Han Kai Qiu Weiwei Liu Kun meng Peilong Yang Key Laboratory of Feed Biotechnology of Ministry of Agriculture and Rural Affairs Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China National Engineering Research Center of Biological Feed Beijing 100081China

Background Fatty liver hemorrhage syndrome(FLHS)becomes one of the most major factors resulting in the laying hen death for caged egg *** study aimed to investigate the therapeutic effects of Lactiplantibacillus plan-tarum(***)FRT4 on FLHS model in laying hen with a focus on liver lipid metabolism,and gut *** The FLHS model of laying hens was established by feeding a high-energy low-protein(HELP)diet,and the treatment groups were fed a HELP diet supplemented with differential proportions of *** *** results indicated that *** FRT4 increased laying rate,and reduced the liver lipid accumulation by regulating lipid metabolism(lipid synthesis and transport)and improving the gut microbiota ***,***-tarum FRT4 regulated the liver glycerophospholipid ***,“gut-liver”axis analysis showed that there was a correlation between gut microbiota and lipid *** The results indicated that *** FRT4 improved the laying performance and alleviated FLHS in HELP diet-induced laying hens through regulating“gut-liver”*** findings reveal that glycerophospholipid metabolism could be the underlying mechanism for the anti-FLHS effect of *** FRT4 and for future use of *** FRT4 as an excellent additive for the prevention and mitigation of FLHS in laying hens.

关键词： Fatty liver hemorrhage syndrome Gut microbiota Lactiplantibacillus plantarum FRT4 Laying hens Lipid metabolism

3B自锁托槽系统和传统直丝托槽系统在排齐与整平阶段上颌牙弓宽度的变化

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广西医科大学学报 2013年第1期30卷 58-60页

作者：蒙红英康娜欧阳晖黎敏蒋燕萍麦文佳黄朝晓广西医科大学附属口腔医院南宁530021

目的:评价3B自锁托槽系统和传统直丝托槽系统在排齐和整平牙列过程中上颌牙弓宽度的变化。方法:选取40例非拔牙的正畸患者,分别应用传统直丝托槽和3B自锁托槽,排齐和整平上颌牙列,在T1阶段和T2阶段(即应用0.018×0.025NiTi方丝排齐和整... 详细信息

目的:评价3B自锁托槽系统和传统直丝托槽系统在排齐和整平牙列过程中上颌牙弓宽度的变化。方法:选取40例非拔牙的正畸患者,分别应用传统直丝托槽和3B自锁托槽,排齐和整平上颌牙列,在T1阶段和T2阶段(即应用0.018×0.025NiTi方丝排齐和整平结束时)分别制取患者上颌模型,然后选取尖牙牙尖间的宽度等测量标志点进行多项测量。结果:自锁托槽组与直丝托槽组牙弓宽度变化最显著的是前磨牙区,各自前后差异均有统计学意义(均P0.05)。结论:对于非拔牙正畸的患者,应用3B自锁托槽和传统直丝托槽系统在排齐和整平牙列阶段,均可使上颌牙弓中后段宽度显著增大;自锁托槽组的牙弓变化量比直丝托槽组大,但优势不明显。

关键词：自锁托槽传统直丝托槽上颌牙弓宽度

Interaction mechanism of cyanide with pyrite during the cyanidation of pyrite and the decyanation of pyrite cyanide residues by chemical oxidation

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 1996-2005页

作者： Wenwen Han hongying Yang Linlin Tong Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

The toxic cyanides in cyanide residues produced from cyanidation process for gold extraction are harmful to the *** is one of the main minerals existing in cyanide *** this work,the interaction of cyanide with pyrite and the decyanation of pyrite cyanide residue were *** revealed that high pH value,high cyanide concentration,and high pyrite dosage promoted the interaction of cyanide with *** cyanidation of pyrite was pseudo-second-order with respect to *** decyanation of pyrite cyanide residue by Na_(2)SO_(3)/air oxidation was *** cyanide removal efficiency was 83.9% after 1 h of reaction time under the optimal conditions of pH value of 11.2,SO_(3)^(2-) dosage of 22 mg·g^(-1),and air flow rate of 1.46 L·min^(-1).X-ray photoelectron spectroscopy analysis of the pyrite samples showed the formation of Fe(Ⅲ)and FeSO_(4) during the cyanidation *** cyanide that adsorbed on the pyrite surface after cyanidation mainly existed in the forms of free cyanide(CN^(-))and ferrocyanide(Fe(CN)_(6)^(4-)),which were effectively removed by Na_(2)SO_(3)/air *** the decyanation process,air intake promoted pyrite oxidation and weakened cyanide adsorption on the pyrite *** study has practical significance for gold enterprises aiming to mitigate the environmental impact related to cyanide residues.

关键词： pyrite cyanide decyanation sodium sulfite/air oxidation cyanide residue

THE ELLIPSOID ARTIFICIAL BOUNDARY METHOD FOR THREE-DIMENSIONAL UNBOUNDED DOMAINS

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Journal of Computational Mathematics 2009年第2期27卷 196-214页

作者： hongying Huang Dehao Yu Information College Zhejiang Ocean University Zhoushan 316004 China LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of SciencesBeijing 100080 China

The artificial boundary method is applied to solve three-dimensional exterior problems. Two kind of rotating ellipsoids are chosen as the artificial boundaries and the exact artificial boundary conditions are derived explicitly in terms of an infinite series. Then the well-posedness of the coupled variational problem is obtained. It is found that error estimates derived depend on the mesh size, truncation term and the location of the artificial boundary. Three numerical examples are presented to demonstrate the effectiveness and accuracy of the proposed method.

关键词： Artificial boundary method Exterior harmonic problem Finite element method,Natural boundary reduction Oblate ellipsoid Prolate ellipsoid.

Performances of a Balanced Hydraulic Motor with Planetary Gear Train

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 760-767页

作者： YU hongying LUO Changjie WANG Huimin School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

The current research of a balanced hydraulic motor focuses on the characteristics of the motor with three planet *** of a balanced hydraulic motor with more than three planet gears are hardly *** order to study the characteristics of a balanced hydraulic motor with planetary gear train that includes more than three planet gears,on the basis of analysis of the structure and working principle of a balanced hydraulic motor with planetary gear train,formulas are deduced for calculating the hydraulic motor＇s primary performance indexes such as displacement,unit volume displacement,flowrate fluctuation ratio,*** of the gears＇ tooth number on displacement and flowrate characteristics are *** order to guarantee the reliability of sealing capability,the necessary conditions that tooth number of the sun gear and the planet gears should satisfy are *** large unit volume displacement and small displacement fluctuation ratio as designing objectives,a balanced hydraulic motor with three planet gears and a common gear motor are designed under the conditions of same displacement,tooth addendum coefficien and clearance *** comparing the unit volume displacement and fluctuation ratio of the two motors,it can be seen that the balanced hydraulic motor with planetary gear train has the advantages of smaller fluctuation ratio and larger unit volume *** results provide theoretical basis for choosing gear tooth-number of this kind of hydraulic motor.

关键词： planetary gear mechanism hydraulic motor tooth number selection

Molybdenum based amorphous and nanocrystalline coatings prepared by high velocity oxy-fuel spraying

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Rare Metals 2012年第4期31卷 355-361页

作者： Fan, Zishuan Yu, hongying Wang, Xudong Center for Corrosion and Protection University of Science and Technology BeijingBeijing 100083China

The high velocity oxy-fuel(HVOF) based thermal spray process has developed as a potential advantageous approach for fabricating various kinds of functional *** this article,the coatings of Mo-based alloy were synthesized using the HVOF *** microstructure and the mechanical properties of the HVOF-processed coatings were investigated using SEM,TEM,XRD,and hardness and wear *** treatment was applied to the as-sprayed coatings to develop the microstructure and its effect on the microstructure and mechanical properties of the coatings was *** is found that the HVOF-processed Mo-based alloy coatings are comprised of an amorphous splat matrix embedded with nano-sized crystalline *** at temperatures over 950 ℃ results into crystallization of the amorphous *** mechanical properties of the as-sprayed coatings are enhanced with annealing temperature up to 750 ℃ and from 950 to 1050 ℃,keeps constant between 750 and 950 ℃,and reduce over 1050 ℃.The change of the mechanical property with the microstructure was illustrated in the study.

关键词： molybdenum based alloy coating amorphous and nanocrystalline phases hardness and tribology anealling high velocity oxy-fuel spraying

Comparative analysis of mitochondrial fragments transferred to the nucleus in vertebrate

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Journal of Genetics and Genomics 2008年第8期35卷 485-490页

作者： hongying Qu Fei Ma Qingwei Li Institute of Marine Genomics ＆ Proteomics Liaoning Normal University Dalian 116029 China

Mitochondrial DNA sequences transferred to the nucleus give rise to the so-called nuclear mitochondrial DNA （numt）. In the GenBank database, 244 numts have been found in six orders of birds （Anseriformes, Columbiformes, Falconiformes, Charadriiformes, Galliformes and Passeriformes）. Sequences alignment （NCBI-BLASTN） was carded out with mitochondrial and corresponding nuclear genome sequences in nine vertebrate species. The sequences with high homology were considered as numts. The number of numts ranged from 15 in chicken to 159 in chimpanzee. The sequences of numts in macaque, chimpanzee, and human spanned 100% of the entire mammalian mitochondrial genome. The reconstructed frequency of the mitochondrial gene transferred to the nucleus demonstrated that the rRNA genes had high frequencies than other mitochondrial genes. Using the RepeatMasker program, the transposable elements were detected in the flanking regions of each numt. The results showed that less than 5% of the flanking sequences were made up of repetitive elements in chicken. The GC content of 5＇- and 3＇-flanking regions of numts in nine species was less than 44%. The analysis of the flanking sequences provided a valuable understanding for future study on mechanism of mitochondrial gene transfer to the nucleus and the site of numt integration.

关键词： mitochondrial DNA numts nuclear insertion flanking sequence vertebrate

A bottleneck-free model for P4P

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Science China(Information Sciences) 2015年第10期58卷 94-108页

作者： LIU Ying ZHANG ShengLin LIU hongying Institute for Network Sciences and Cyberspace Tsinghua University School of Mathematics and Systems Science Beihang University

Provider Portal for Applications(P4P) is a model aiming to incorporate(peer to peer) P2 P applications with Internet Service Providers(ISPs) and improve the performance of the both ISP and the P2 P applications. In this study, we have analyzed the relationship between the link traffic and the P-distance, which is the core interface of P4 P. In addition, the limitation of P4 P in dealing with network applications having bottleneck links is illustrated. Furthermore, taking link utility function as the optimization objective, we propose a Bottleneck-Free model for P4P(BFP), making the traffic produced by P2 P applications more homogeneous,which can reduce the peak link utilization, protect bottleneck links, and thereby improve both the network efficiency and the P2 P performance. We have built a simulation platform based on Bit Torrent and conducted extensive simulations. The simulation results demonstrate that BFP achieves a lower cost for ISPs and a better performance for P2 P applications than P4 P and native P2 P applications, both in intra-domain and inter-domain settings. BFP performs steadily in different topologies and swarm sizes, proving that it is scalable and easy to deploy.

关键词： subgradient method P2P traffic engineering cooperative model duality