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Analysis of moisture diffusivity of larch timber during convective drying condition by using Crank＇s method and Dincer＇s method

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Journal of Forestry Research 2007年第3期18卷 199-202页

作者： zhan jian-feng gu ji-you cai ying-chun College of Material Science and Engineering Northeast Forestry University Harbin 150040 P. R. China

Two analytical procedures （Crank＇s method and Dincer＇s method） for porous solid materials were reevaluated and used to determine moisture diffusion coefficients and moisture transfer coefficients for larch lumber subjected to drying. A diffusion-like equation was used to describe drying process data. The lumber was idealized in the modeling as infinite plates. The moisture transport process inside the board was assumed to be one-dimensional. The macroscopic drying kinetics curves of larch timber at particular conditions were determined experimentally. Based on these data, calculation for both the moisture diffusion coefficients and moisture transfer coefficients by the Dincer＇s analytical procedure were made. The dynamic moisture diffusion coefficients by the traditional Crank＇s method were calculated. In general, diffusion coefficients calculated by the Dincer＇s method were all higher than those by Crank＇s method. These results could be due to the differences between two analytical methods and also different characteristics between solid moisture diffusion process and heat transfer process. Therefore the analysis and solution procedures of moisture diffusion differential equations need to be adapted in the future. With drying temperature＇s increasing moisture diffusion coefficient （D） and moisture transfer coefficient （k） increases accordingly. Also the relationships between diffusion coefficients and temperature as well as material moisture contents were analyzed by using Arrhenius equation and bound water transport theory.

关键词： Larch timber Wood dry Moisture diffusion coefficient Moisture transfer coefficient Mathematical model

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落叶松板材常规干燥过程的动态机械吸附特性

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北京林业大学学报 2009年第2期31卷 108-113页

作者：战剑锋顾继友蔡英春东北林业大学材料科学与工程学院

为探索木材常规干燥机械吸附蠕变的动态发展模式,该文在实验室条件下对50 mm厚兴安落叶松板材进行常规干燥,用切片法测定了沿厚度方向的横纹弦向干缩应变、弹性应变、黏弹性应变的一维分布情况与变化趋势,并测定了不同尺寸规格及不同预... 详细信息

为探索木材常规干燥机械吸附蠕变的动态发展模式,该文在实验室条件下对50 mm厚兴安落叶松板材进行常规干燥,用切片法测定了沿厚度方向的横纹弦向干缩应变、弹性应变、黏弹性应变的一维分布情况与变化趋势,并测定了不同尺寸规格及不同预处理工艺下木材试件的自由干缩变形。根据高聚物流变学理论与木材机械吸附蠕变理论,分析了干燥过程中木材厚度方向不同位置的机械吸附蠕变变形的变化规律及其主要影响因子,概括了木材表层与心层的机械吸附蠕变变形的典型发展模式。结论如下：可以采用线性函数与指数函数来分别描述含水率在低于20%和高于20%阶段的木材自由干缩率曲线,相关性较好;木材干燥机械吸附蠕变现象具有极大变异性,与干燥应力模式及应力发展间存在相互作用;在含水率低于特定温度对应下的纤维饱和点2%~4%时,木材表层的拉伸机械吸附蠕变应变与心层的压缩机械吸附蠕变应变均接近极大值;机械吸附蠕变在一定范围内的增大将有助于干燥应力松弛,机械吸附蠕变数值可作为木材干燥工艺调整的参考因子。

关键词：落叶松木材干燥干燥应力机械吸附蠕变

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落叶松板材常规干燥过程的动态黏弹性特性

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北京林业大学学报 2009年第1期31卷 125-129页

作者：战剑锋顾继友蔡英春东北林业大学材料科学与工程学院

为了研究木材常规干燥过程黏弹性应变的发展模式与相对数量级,并为准确区分黏弹性应变与机械吸附应变提供理论依据,该文在实验室条件下对50 mm厚兴安落叶松板材进行常规干燥,使用切片法测定沿厚度方向的横纹弦向干缩应变、弹性应变、黏... 详细信息

为了研究木材常规干燥过程黏弹性应变的发展模式与相对数量级,并为准确区分黏弹性应变与机械吸附应变提供理论依据,该文在实验室条件下对50 mm厚兴安落叶松板材进行常规干燥,使用切片法测定沿厚度方向的横纹弦向干缩应变、弹性应变、黏弹性应变的一维分布情况与变化趋势。基于高聚物与复合材料黏弹性理论,重点定性分析了木材干燥过程中干燥介质温度、蠕变恢复时间、干燥阶段等因子对木材厚度方向不同位置黏弹性应变特性的影响。结果表明:在环境平衡含水率保持在特定水平下,干燥介质温度水平与测定的拉伸弹性应变极值间具有一定正相关性;木材干燥过程中黏弹性应变的发展模式与弹性应变类似,经充分恢复后黏弹性应变的数值略大于弹性应变;木材表层、芯层在干燥过程中具有不同的黏弹性演化模式,干燥温度对木材表芯层黏弹性应变转换有一定影响,这种作用主要是由于不同温度条件下木材含水率梯度所导致的;根据试验测定的木材表层、芯层在3、62、4 h 3个应力释放时间内所达到的黏弹性应变极值,分别给出了干燥过程各阶段落叶松板材表层与芯层黏弹性应变恢复时间的推荐值。

关键词：落叶松木材干燥干燥应力弹性应变黏弹性应变

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Effects of the total physical activity and its changes on incidence, progression, and remission of hypertension

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Journal of Geriatric Cardiology 2021年第3期18卷 175-184页

作者： Can cai Fang-Chao LIU jian-Xin LI Ke-Yong HUANG Xue-Li YANG ji-chun CHEN Xiao-Qing LIU jie CAO Shu-feng CHEN Chong SHEN Ling YU Fang-Hong LU Xian-Ping WU Lian-Cheng ZHAO ying LI Dong-Sheng HU jian-feng HUANG Xiao-Yang ZHOU Xiang-feng LU Dong-feng gu Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060China Key Laboratory of Cardiovascular Epidemiology&Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Tianjin Key Laboratory of Environment Nutrition and Public HealthDepartment of Occupational and Environmental HealthSchool of Public HealthTianjin Medical UniversityTianjin 300070China Division of Epidemiology Guangdong Provincial People’s Hospital and Cardiovascular InstituteGuangzhou 510080China Department of Epidemiology and Biostatistics School of Public HealthNanjing Medical UniversityNanjing 211166China Department of Cardiology Fujian Provincial HospitalFuzhou 350014China Cardio-Cerebrovascular Control and Research Center Institute of Basic MedicineShandong Academy of Medical SciencesJinan 250062China Sichuan Center for Disease Control and Prevention Chengdu 610041China Department of Epidemiology and Health Statistics School of Public HealthShenzhen University Health Science CenterShenzhen 518060China

OBJECTIVES Moderate to vigorous physical activity is recommended to prevent hypertension according to the current ***,the degree to which the total physical activity(TPA)and its changes benefit normotensives and hypertensives is *** aimed to examine the effects of TPA and its changes on the incidence,progression,and remission of hypertension in the large-scale prospective *** A total of 73,077 participants(55,101 normotensives and 17,976 hypertensives)were eligible for TPA *** a mean follow-up of 7.16 years(394,038 person-years),12,211 hypertension cases were *** was estimated as metabolic equivalents and categorized into *** proportional hazards regression and multivariable logistic regression were used to estimate associations of TPA and changes in TPA with incident hypertension and progression/remission of *** Compared with the lowest quartile of TPA,normotensives at the third and the highest quartile had a decreased risk of incident hypertension,with hazard ratios(HRs)of 0.86[95%confidence interval(CI):0.81−0.91]and 0.81(95%CI:0.77−0.86),*** at the highest quartile of TPA demonstrated a decreased risk of progression of hypertension[odds ratio(OR)=0.87,95%CI:0.79−0.95],and an increased probability of hypertension remission(OR=1.17,95%CI:1.05−1.29).Moreover,getting active from a sedentary lifestyle during the follow-up period could reduce 25%(HR=0.75,95%CI:0.58−0.96)risk of incident hypertension,whereas those becoming sedentary did not achieve benefit from initially being *** Our findings indicated that increasing and maintaining TPA levels could benefit normotensives,whereas higher TPA levels were needed to effectively control progression and improve remission of *** activity played undoubtedly an essential role in both primary and secondary prevention of hypertension.

关键词： hypertension remission prevention

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落叶松板材干燥过程的结合水扩散系数

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南京林业大学学报（自然科学版） 2008年第4期32卷 6-10页

作者：战剑锋顾继友蔡英春东北林业大学材料科学与工程学院黑龙江哈尔滨150040

采用3种扩散偏微分方程求解方法研究了落叶松干燥结合水扩散系数;分析不同干燥介质条件下,10 mm、20 mm厚落叶松板材的一维径向非稳态扩散试验数据,确定干燥动力学曲线;对不同求解方法的水分扩散系数进行比较分析,研究干燥介质温度、湿... 详细信息

采用3种扩散偏微分方程求解方法研究了落叶松干燥结合水扩散系数;分析不同干燥介质条件下,10 mm、20 mm厚落叶松板材的一维径向非稳态扩散试验数据,确定干燥动力学曲线;对不同求解方法的水分扩散系数进行比较分析,研究干燥介质温度、湿度、试件厚度、含水率阶段等因素对水分扩散系数的影响机制。结果表明:在特定的环境湿度条件下,扩散系数随温度升高而增大,在3种分析求解方法中,Crank方法的扩散系数与温度间具有的线性关系最为显著;在温度为80℃的干燥试验中,随平衡含水率(EMC)降低,3种方法的扩散系数均呈现出显著增大趋势;相同干燥介质条件下,厚度为20 mm试件的扩散系数均明显高于10 mm试件扩散系数,这种趋势随温度的升高而愈显突出;纤维饱和点以下,木材结合水扩散系数随含水率降低呈指数规律降低。

关键词：落叶松木材干燥结合水扩散扩散系数

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Microbial Community Changes Along a Land-Use Gradient of Desert Soil Origin

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Pedosphere 2012年第5期22卷 593-603页

作者： WANG Bao-zhan zhanG cai-Xia LIU ji-Liang ZENG Xiao-Wei LI feng-Rui WU Yu-Cheng LIN Xian-gui XIONG Zheng-Qin XU jian jiA Zhong-Jun Institute of Soil Science Chinese Academy of SciencesNanjing 210008(China) Nanjing Agricultural University Nanjing 210095(China) Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000(China) Qingdao Institute of BioEnergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101(China)

Soil harbors remarkably stabilize bacterial communities at the phylum level. However, no two soils have exactly the same structure of bacterial phyla. The structure of microbial community is strongly influenced by the type of land-use through changes in soil attributes. Using high-throughput pyrosequencing and quantitative polymerase chain reaction techniques, soil microbial community structures were investigated along a land-use gradient of 100- and 27-year farmlands, a 33-year Pinus forest, a 28-year poplar forest, and a 21-year shrubland, as well as a native desert from which all cultivated systems were converted. The results revealed that the dominant phylotypes in the native soil comprised primarily of Alphaproteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes, accounting for 〉 71.4% of the total bacterial 16S rRNA sequence reads. Changes in land-use led to a significant decrease in these dominant phylotypes down to 33.4%. In contrast, the phylotypes with low abundance, such as Acidobaeteria, Chloroflexi, Nitrospira, and Gammaproteobaeteria, increased sharply from 4.5%-5.9% in the native soil to 20.9% 30.2% of the total 16S rRNA gene sequences in the cultivated soils except for the soil from the shrubland. These contrasting changes in the major taxa appear to be correlated with the changes in soil attributes. For instance, bacterial and archaeal amoA genes were found to be 960- and 3 800-fold more abundant in the soil from the 100-year farmland than the native soil. The changes in numerically less dominant nitrifying phylotypes are consistent with soil inorganic nitrogen dynamics. Quantification of the 16S rRNA genes demonstrated that bacteria and archaea were about two to three orders of magnitude more abundant in the cultivated soil than in the native soil. Hence, land-use type affects the soil bacterial community structure, which has profound consequences on ecosystem function.

关键词： amoA ecosystem functions land-use type polymerase chain reaction pyrosequencing

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Urinary Creatinine Concentrations and Its Explanatory Variables in General Chinese Population:Implications for Creatinine Limits and Creatinine Adjustment

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Biomedical and Environmental Sciences 2022年第10期35卷 899-910页

作者： ji Sai Sai LYU Yue Bin QU ying Li HU Xiao jian LU Yi Fu cai Jun Fang SONG Shi Xun zhanG Xu LIU ying chun YANG Yan Wei zhanG Wen Li LI Ya Wei zhanG Ming Yuan CHEN Chen LI Cheng Cheng LI Zheng gu Heng LIU Ling cai jia Yi QIU Tian FU Hui ji S.John ZHAO feng ZHU ying CAO Zhao jin SHI Xiao Ming China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China School of Public Health Jilin UniversityChangchun 130021JilinChina Vanke School of Public Health Tsinghua UniversityBeijing 100084China

Objective The study aimed to analyze the applicability of the World Health Organization’s exclusionary guidelines for Urinary creatinine(Ucr)in the general Chinese population,and to identify Ucr related *** We conduct a cross-sectional study using baseline data from 21,167 participants in the China National Human Biomonitoring *** linear models and restricted cubic splines(RCS)were used to analyze the associations between explanatory variables and Ucr *** The geometric mean and median concentrations of Ucr in the general Chinese population were 0.90 g/L and 1.01 g/L,*** 9.36%samples were outside 0.3-3.0 g/L,including 7.83%below the lower limit and 1.53%above the upper *** age,male,obesity,smoking,higher frequency of red meat consumption and chronic kidney disease were associated significantly with higher concentrations of *** of the RCS showed Ucr was positively and linearly associated with body mass index,inversely and linearly associated with systolic blood pressure,diastolic blood pressure,triglycerides level,and glomerular filtration rate,and were non-linearly associated with *** The age-and gender-specific cut-off values of Ucr that determine the validity of urine samples in the general Chinese population were *** avoid introducing bias into epidemiologic associations,the potential predictors of Ucr observed in the current study should be considered when using Ucr to adjust for variations in urine dilution.

关键词： Biomonitoring Urine Hydration correction Creatinine

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Epitaxial growth and transport properties of compressively-strained Ba_(2)IrO_(4) films

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Chinese Physics B 2021年第8期30卷 492-495页

作者： Yun-Qi Zhao Heng zhang Xiang-Bin cai Wei guo Dian-Xiang ji Ting-Ting zhang Zheng-Bin gu jian Zhou Ye Zhu Yue-feng Nie National Laboratory of Solid State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Applied Physics Research Institute for Smart EnergyThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Ba_(2)IrO_(4) is a sister compound of the widely investigated Sr_(2)IrO_(4) and has no IrO_(6) octahedral rotation nor net canted antiferromagnetic moment,thus it acts as a system more similar to the high-T_(c) *** this work,we synthesize the Ba_(2)IrO_(4) epitaxial films by reactive molecular beam epitaxy and study their crystalline structure and transport properties under biaxial compressive *** resolution scanning transmission electron microscopy and x-ray diffraction confirm the high quality of films with partial strain *** compressive epitaxial strain,the Ba_(2)IrO_(4) exhibits the strain-driven enhancement of the conductivity,consistent with the band gap narrowing and the stronger hybridization of Ir-t_(2g) and O-2p orbitals predicted in the first-principles calculations.

关键词： molecular beam epitaxy iridate oxides epitaxial strain transport properties

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Advanced Space-based Solar Observatory(ASO-S):an overview

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Research in Astronomy and Astrophysics 2019年第11期19卷 3-10页

作者： Wei-Qun Gan Cheng Zhu Yuan-Yong Deng Hui Li Yang Su Hai-ying zhang Bo Chen Zhe zhang jian Wu Lei Deng Yu Huang jian-feng Yang ji-Jun Cui jin Chang Chi Wang ji Wu Zeng-Shan Yin Wen Chen Cheng Fang Yi-Hua Yan Jun Lin Wei-Ming Xiong Bin Chen Hai-Chao Bao cai-Xia Cao Yan-Ping Bai Tao Wang Bing-Long Chen Xin-Yu Li Ye zhang Li feng jiang-Tao Su ying Li Wei Chen you-Ping Li ying-Na Su Hai-Yan Wu Mei gu Lei Huang Xue-Jun Tang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201203China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China Changchun Institute of Optics Fine Mechanics and PhysicsChangchun 130033China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650011China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China Beijing Special Engineering and Design Institute Beijing 100028China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China Shanghai Academy of Spaceflight Technology Shanghai 201109China

The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed for the 25 th solar maximum by the Chinese solar *** scientific objectives are to study the relationships between the solar magnetic field,solar flares and coronal mass ejections(CMEs).Three payloads are deployed:the Full-disk vector Magneto Graph(FMG),the Lyman-αSolar Telescope(LST)and the Hard X-ray Imager(HXI).ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field,non-thermal imaging of solar flares,and the initiation and early propagation of CMEs on a single ***-S is scheduled to be launched into a 720 km Sun-synchronous orbit in *** paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.

关键词： space vehicles instruments-Sun magnetic fields-Sun flares-Sun CMEs-Sun UV radiation-Sun X-ray,gamma-rays

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Total Reaction Cross Section Measurements at Intermediate Energy for the Proton Halo Candidate ^(23)Al and Its Neighbours

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Chinese Physics Letters 2001年第9期18卷 1189-1191页

作者： cai Xiang-Zhou SHEN Wen-Qing feng Jun FANG De-Qing ZHU Zhi-Yuan jianG Wei-Zhou MA Yu-Gang zhanG Hu-Yong ZHONG Chen YU Li-Ping zhan Wen-Long guO Zhong-Yan XIAO gu-Qhig WANG jian-Song ZHU Yong-Tai WANG jin-Chuan LI jia-Xing WANG Meng WANG jian-feng NING Zhen-jiang WANG Quan-jin CHEN Zhi-Qiang Shanghai Institute of Nuclear Research Chinese Academy of SciencesShanghai 201800 CCAST World Laboratory P.O.Box 8730 Beijing 100080 Institute of Modern Physics Chinese Academy of SciencesLanzhuo 730000 Department of Physics Ningbo UniversityNingbo 315211

Total reaction cross sections σR for some proton-rich isotones (N = 10) near ^(23)Al on a carbon target have been measured at intermediate energies in the experiment performed at the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou. The Z-dependence of σR shows a remarkable enhancement for ^(23)Al relative to its neighbours. The difference factor d has been deduced from the measured σR by using the Glauber or Boltzmann-Uehling-Uhlenbeck models. From the above analysis, a possible one-proton halo structure is suggested for ^(23)Al.

关键词： deduced Total Boltzmann

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