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Mass and heat transfer mechanism in wood during radio frequency/vacuum drying and numerical analysis

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Journal of Forestry Research 2017年第1期28卷 205-213页

作者： xiaoran Jia Jingyao Zhao Yingchun Cai Northeast Forestry University Harbin 150040 People's Republic of China

The mass and heat transfer mechanisms during radio frequency/vacuum （RF/V） drying of square-edged timber were analyzed and discussed in detail, and a new one-dimensional mathematical model to describe the transport phenomena of mass and heat during continuous RF/V drying was derived from conservation equations based on the mass and heat transfer theory of porous materials The new model provided a relatively fast and efficient way to simulate vacuum drying behavior assisted by dielectric heating. Its advantages compared with the conventional models include：（1） Each independent vari- able has a separate control equation and is solved inde- pendently by converting the partial differential equation into a difference equation with the finite volume method; （2） The calculated data from different parts of the specimen can be displayed in the evolution curves, and the change law of the,parameters can be better described. After analyzing the calculated results, most of the important phenomena observed during RF/V drying were adequately described by this model.

关键词： Bulk flow Mathematical model Numerical analysis RF/V drying transfer mechanism

MdVQ37 overexpression reduces basal thermotolerance in transgenic apple by affecting transcription factor activity and salicylic acid homeostasis

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Horticulture Research 2021年第1期8卷 2892-2907页

作者： Qinglong Dong Dingyue Duan Wenqian zheng Dong Huang Qian Wang xiaoran Li Ke Mao Fengwang Ma State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F University712100 YanglingShaanxiChina

High temperature(HT)is one of the most important environmental stress factors and seriously threatens plant growth,development,and *** motif-containing proteins are transcriptional regulators that have been reported to regulate plant growth and developmental processes,including responses to biotic and abiotic ***,the relationships between VQ motif-containing proteins and HT stress have not been studied in depth in *** this study,transgenic apple(Malus domestica)plants overexpressing the apple VQ motif-containing protein-coding gene(MdVQ37)were exposed to HT stress,and the transgenic lines exhibited a heat-sensitive *** addition,physiological and biochemical studies revealed that,compared with WT plants,transgenic lines had lower enzymatic activity and photosynthetic capacity and lower amounts of nonenzymatic antioxidant system metabolites under HT *** analysis revealed 1379 genes whose expression differed between the transgenic lines and WT *** and KEGG pathway analyses showed that transcription factor activity and plant hormone signaling pathways were differentially influenced and enriched in the transgenic *** acid(SA)content analysis indicated that overexpression of MdVQ37 reduced the content of endogenous SA by regulating the expression of SA catabolism-related genes,which ultimately resulted in disruption of the SA-dependent signaling pathway under HT *** application of SA slightly increased the survival rate of the transgenic lines under HT *** together,our results indicate that apple MdVQ37 has a regulatory function in basal thermotolerance by modulating the activity of transcription factors and SA ***,this study provides novel insights that improve our understanding of the various functions of VQ motif-containing proteins.

关键词： homeostasis slightly expressing

中国北方甜菜土壤碱解氮丰缺指标与适宜施氮量研究

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中国糖料 2019年第2期41卷 14-17页

作者：孙洪仁张吉萍吕玉才郑笑冉张利霞宋琼林柏森中国农业大学草地研究所北京100193 北京六凯农业科技有限公司北京100095 凯风新农(北京)科技有限公司北京100095 赤峰众益糖业有限公司内蒙古赤峰024000 呼伦贝尔包商银行内蒙古海拉尔021000 赤峰绿璐种业有限公司内蒙古赤峰024000

为了给甜菜测土施肥提供科学依据,采用零散实验数据整合法、土壤养分含量与缺素处理相对产量回归方程法和"养分平衡—地力差减法"确定适宜施肥量新应用公式,开展了我国北方甜菜土壤碱解氮丰缺指标与适宜施氮量研究。结果表明,中国北方... 详细信息

为了给甜菜测土施肥提供科学依据,采用零散实验数据整合法、土壤养分含量与缺素处理相对产量回归方程法和"养分平衡—地力差减法"确定适宜施肥量新应用公式,开展了我国北方甜菜土壤碱解氮丰缺指标与适宜施氮量研究。结果表明,中国北方甜菜土壤碱解氮第2～6级丰缺指标依次为>429、115～429、31～115、9～31和≤9 mg/kg。当氮肥当季利用率40%、目标产量30～90 t/hm^2时,土壤碱解氮丰缺级别第2～6级的适宜施氮量范围依次为34～101、68～203、101～304、135～405和169～506 kg/hm^2。

关键词：甜菜中国北方测土施肥土壤碱解氮丰缺指标氮肥施用量

中国北方甜菜土壤速效钾丰缺指标与适宜施钾量研究

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中国糖料 2020年第1期42卷 45-49页

作者：孙洪仁张吉萍吕玉才郑笑冉张利霞宋琼林柏森中国农业大学草业科学与技术学院北京100193 北京六凯农业科技有限公司北京100095 凯风新农(北京)科技有限公司北京100095 赤峰众益糖业有限公司内蒙古赤峰024000 呼伦贝尔包商银行内蒙古海拉尔021000 赤峰绿璐种业有限公司内蒙古赤峰024000

为了给甜菜测土施肥提供科学依据,采用零散实验数据整合法、缺素处理相对产量与土壤养分含量回归方程法和“养分平衡—地力差减法”确定适宜施肥量新应用公式,开展了我国北方甜菜土壤速效钾丰缺指标与适宜施钾量研究。结果表明,中国北... 详细信息

为了给甜菜测土施肥提供科学依据,采用零散实验数据整合法、缺素处理相对产量与土壤养分含量回归方程法和“养分平衡—地力差减法”确定适宜施肥量新应用公式,开展了我国北方甜菜土壤速效钾丰缺指标与适宜施钾量研究。结果表明,中国北方甜菜土壤速效钾(NH4OAc-K)第1~5级丰缺指标依次为>409、224~409、123~224、68~123和≤68 mg/kg。当钾肥当季利用率40%、目标产量30~90 t/hm^2时,土壤速效钾丰缺级别第1~5级的适宜施钾量范围依次为0~0、41~124、83~248、124~371和165~495 kg/hm^2。

关键词：甜菜中国北方测土施肥土壤速效钾丰缺指标钾肥施肥量

Spatiotemporal changes of typical glaciers and their responses to climate change in Xinjiang,Northwest China

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Journal of Arid Land 2022年第5期14卷 502-520页

作者： HUANG xiaoran BAO Anming GUO Hao MENG Fanhao ZHANG Pengfei zheng Guoxiong YU Tao QI Peng Vincent NZABARINDA DU Weibing State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan School of Geography and Tourism Qufu Normal UniversityRizhao 276800China College of Geographical Science Inner Mongolia Normal UniversityHohhot 010022China Xuchang University Xuchang 461000China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuo 454000China

Glaciers are highly sensitive to climate change and are undergoing significant changes in *** this study,we analyzed the spatiotemporal changes of typical glaciers and their responses to climate change in the period of 1990-2015 in 4 different mountainous sub-regions in Xinjiang Uygur Autonomous Region of Northwest China:the Bogda Peak and Karlik Mountain sub-regions in the Tianshan Mountains;the Yinsugaiti Glacier sub-region in the Karakorum Mountains;and the Youyi Peak sub-region in the Altay *** standardized snow cover index(NDSI)and correlation analysis were used to reveal the glacier area changes in the 4 sub-regions from 1990 to *** areas in the Bogda Peak,Karlik Mountain,Yinsugaiti Glacier,and Youyi Peak sub-regions in the period of 1990-2015 decreased by 57.7,369.1,369.1,and 170.4 km^(2),*** of glacier area center of gravity showed that quadrant changes of glacier areas in the 4 sub-regions moved towards the *** area on the south aspect of the Karlik Mountain sub-region was larger than that on the north aspect,while glacier areas on the north aspect of the other 3 sub-regions were larger than those on the south *** precipitation in the Karlik Mountain sub-region inhibited the retreat of glaciers to a certain ***,glacier area changes in the Bogda Peak and Youyi Peak sub-regions were not sensitive to the increased *** a seasonal time scale,glacier area changes in the Bogda Peak,Karlik Mountain,Yinsugaiti Glacier,and Youyi Peak sub-regions were mainly caused by accumulated temperature in the wet season;on an annual time scale,the correlation coefficient between glacier area and annual average temperature was-0.72 and passed the significance test at P<0.05 level in the Karlik Mountain *** findings of this study can provide a scientific basis for water resources management in the arid and semi-arid regions of Northwest China in the context of global warmin

关键词： glacier area change normalized snow cover index(NDSI) climate change remote sensing Altay Mountains Tianshan Mountains Karakorum Mountains

Study on the effect of pressure on the equilibrium and stability of the solid-liquid interface in solidification of binary alloys

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Science China(Technological Sciences) 2011年第2期54卷 479-483页

作者： HUANG xiaoran HAN ZhiQiang LIU BaiCheng Key Laboratory for Advanced Materials Processing Technology Ministry of Education Tsinghua University Beijing 100084 China State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

The equilibrium of the solid-liquid interface in pressurized solidification process of binary alloys was studied using the Gibbs theory, and the stability of the solid-liquid interface was discussed based on the consideration of the effects of pressure on the diffusion coefficient, the interface growth rate and tile equilibrium liquid composition. A mathematical description of the equi- librium status, the relationship of temperature, pressure, composition and interfacial tension was obtained, and further, a mathematical representation of the curvature radius of solid-liquid interface was developed, which facilitates a thorough understanding of the controlled variables of the interfacial stability.

关键词： pressurized solidification binary alloy interfacial equilibrium interfacial stability

IL-21 accelerates xenogeneic graft-versus-host disease correlated with increased B-cell proliferation

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Protein & Cell 2013年第11期4卷 863-871页

作者： xiaoran Wu Yi Tan Qiao Xing Shengdian Wang Key Laboratory of Infection and Immunity Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China

Graft-versus-host disease(GVHD)is a prevalent and potential complication of hematopoietic stem cell *** animal model,xenogeneic GVHD(X-GVHD),that mimics accurately the clinical presentation of GVHD would provide a tool for investigating the mechanism involved in disease *** models indi-cated that inhibiting IL-21 signaling was a good therapy to reduce GVHD by impairing T cell *** sought to investigate the effect of exogenous human IL-21 on the process of *** this study,human IL-21 was expressed by hydrodynamic gene delivery in BALB/c-Rag2−/−IL-2Rγc−/−(BRG)immunodeficient mice which were intravenously transplanted human peripheral blood mononuclear cells(hPBMCs).We found that human IL-21 exacerbated X-GVHD and resulted in rapid *** early as 6 days after hPBMCs transplanted to BRG mice,a marked expansion of human CD19+B cells,but not T cells,was observed in spleen of IL-21-treated ***-pared with control group,IL-21 induced robust immuno-globulin secretion,which was accompanied by increased accumulation of CD19+CD38high plasma cells in *** addition,we demonstrated that B-cell depletion was able to ameliorate *** results are the fi rst to fi nd in vivo expansion and differentiation of human B cells in response to IL-21,and reveal a correlation between the expansion of B cells and the exacerbation of xenogeneic *** fi ndings show evidence of the involvement of B cells in X-GVHD and may have implications in the treat-ment of the disease.

关键词： IL-21 B cell xenogeneic GVHD immunode-fi cient mice immunoglobulin

Multiphase Flow Simulation of New Vapor Distributor in Dividing Wall Column and Control Mechanism

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China Petroleum Processing & Petrochemical Technology 2020年第3期22卷 109-118页

作者： Hu Yuqi Li xiaoran Li Chunli National-Local Joint Engineering Laboratory for Energy Conservation of Chemical Process Integration and Resources Utilization School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130

A new vapor distributor based on the Coanda effect is added to the Dividing Wall column(DWC),and the multiphase flow simulation is performed using ANSYS Fluent by this *** results show that with the addition of the liquid phase,the new vapor distributor still follows the Coanda ***,the vapor is ejected from the slits of the distributor to take away the surrounding vapor,and a negative pressure is formed under the distributor,so as to achieve the purpose of regulating *** to the working principle of vapor distributor,a certain amount of vapor is drawn out from a position of prefractionator,which is equivalent to the vapor ejected by the *** same amount of vapor is fed into the main column,which corresponds to the gas phase at the inlet of the *** Rv is adjusted by changing the speed of the input or output *** results show that adding this control mechanism on the basis of temperature or concentration control structure can better achieve the effect of vapor distribution.

关键词： Aspen Plus ANSYS fluent DWC simulation optimization control mechanism

Heritage tourism evolution in Guangfu Ancient City,Hebei Province,China:an analysis with the improved creative destruction model

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Built Heritage 2022年第3期6卷 28-42页

作者： Menghan Wang xiaoran Bai Mingming Su School of Environment&Natural Resources Renmin University of ChinaBejing 100872China

Ancient cities and towns are popular tourism destinations *** this paper,Guangfu Ancient City in Yongnian County,Hebei Province,China,is taken as the case study and the modifed creative destruction model is applied as the analytical framework to evaluate the multiactor dynamics of heritage tourism development.A mixed method approach is adopted,including a local resident survey,in-depth interviews with staf of the Guangfu Ancient City tourism site and government ofcials responsible for the heritage conservation and tourism development of the site,and a review of online tourist reviews,relevant government documents and *** on the modifed creative destruction model,local residents’attitudes towards tourism development,changes in tourist numbers,the level of business and government investments,and the motivations of diferent stakeholders in tourism development are assessed by synthesising on-site research,historical data and other ***,the tourism development stages for Guangfu Ancient City are identifed as the precommodifcation stage before 2006,the early commodifcation stage from 2006 to 2011 and the advanced commodifcation stage from 2012 to *** fndings indicate that with rapid increases in investments from both corporate and government sources and in the number of tourists,the attitude of local residents towards tourism development remained *** results show that instead of entering the initial destruction stage,Guangfu Ancient City is in the transition stage from advanced commodifcation to creative enhancement given the government’s dominant role in tourism development,the heritage conservation motives of tourism entrepreneurs,the benefts to residents from tourism development ensured by government policies,and the shift in tourist type to postmodern tourists with double *** applicability of the modifed creative destruction model is further discussed,and policy and management recommendations are generated to support

关键词： Creative destruction Creative enhancement Heritage tourism Tourism commercialisation Stakeholder Guangfu Ancient City