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晋西黄土区典型小流域不同土层土壤容重分布特征及其影响因素

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生态学杂志 2024年第3期43卷 609-615页

作者：王思敏张红丽张恒硕左启林查同刚北京林业大学水土保持学院北京100083 水利部水土保持监测中心北京100000 山西吉县森林生态系统国家野外科学观测研究站北京100083

为了解黄土区不同土层土壤容重分布特征及其影响因素,本研究以晋西黄土区蔡家川流域为对象,运用经典统计学和地统计学方法分析了蔡家川流域98个样点不同土层(0~20、20~40、40~60、60~80和80~100 cm)土壤容重的分布特征以及主要影响因子... 详细信息

为了解黄土区不同土层土壤容重分布特征及其影响因素,本研究以晋西黄土区蔡家川流域为对象,运用经典统计学和地统计学方法分析了蔡家川流域98个样点不同土层(0~20、20~40、40~60、60~80和80~100 cm)土壤容重的分布特征以及主要影响因子及其贡献率。结果表明:(1)土壤容重介于0.79~1.78 g·cm^(-3),在0~100 cm深的土层中随土层深度的增加而增加;土壤容重变异程度随土层深度的增加而减小,在0~40和40~100 cm处分别表现为中等和弱度变异。(2)土壤容重在0~40 cm土层的最佳拟合模型为高斯模型,在40~100 cm土层为指数模型;随土层增加土壤容重空间依赖性下降,在0~20、20~60和60~100 cm土层分别呈强度、中度和弱度空间依赖。(3)0~40 cm土层土壤容重主要受植被和土壤因素影响,而40~100 cm土层土壤容重主要受海拔和土壤因素的影响,表明30多年植被恢复对土壤容重的影响主要集中于表层。以上结果对深入认知植被恢复背景下区域土壤容重分布规律、科学评估区域植被恢复生态效益和生态服务具有重要参考价值。

关键词：土壤容重土层植被恢复黄土区

专利视角下全球谷物副产物加工产业技术发展态势与我国发展对策研究

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中国发明与专利 2024年第6期21卷 29-38页

作者：查宝萍李丹陈中伟唐恒江苏大学知识产权学院镇江212013 江苏大学食品与生物工程学院镇江212013

为给大食物观背景下我国谷物副产物加工产业的发展提供指导,通过incoPat专利数据库统计近30年全球相关专利,采用专利计量研究方法,从宏观、中观和微观层面对全球谷物副产物加工专利整体态势、技术领域、运营布局进行了解析。与发达国家... 详细信息

为给大食物观背景下我国谷物副产物加工产业的发展提供指导,通过incoPat专利数据库统计近30年全球相关专利,采用专利计量研究方法,从宏观、中观和微观层面对全球谷物副产物加工专利整体态势、技术领域、运营布局进行了解析。与发达国家相比,我国谷物副产物加工正处于快速发展期,创新优势积聚于制备技术和加工技术;技术储备主要在高校科研阶段,高价值专利相对较少,专利转化率相对较低,技术创新驱动产业发展能力尚不足。研磨、谷物膳食纤维是产业的重点发展方向。我国应积极推进高校与企业的产学研合作,大力培育在谷物副产物研磨粉碎技术、谷物膳食纤维、谷物油脂产品等方面的高价值专利,促进科技成果转化落地,助推谷物副产物增值加工产业的高质量发展。

关键词：谷物副产物专利分析技术发展方向增值加工大食物观

Assessing vegetation community distribution characteristics and succession stages in mountainous areas hosting coming Winter Olympics games

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Journal of Mountain Science 2021年第11期18卷 2870-2887页

作者： zha.g heng-shuo zha Tong-gang YU Yang JI Xiao-dong JESÚS Rodrigo-Comino School of Soil and Water Conservation Beijing Forestry UniversityQinghua East Road 35Beijing 100083China Jixian National Forest Ecosystem Research Network Station CNERNBeijing Forestry UniversityBeijing 100083China Departamento de Análisis geográfico Regional y geografía Física Facultad de Filosofía y LetrasCampus Universitario de CartujaUniversity of Granada18071 GranadaSpain

Alpine mountain ecosystem shows strong interactions between abiotic and biotic *** also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturbance risk areas in alpine mountains are increasing,it is necessary to understand the relationship between environmental factors and plant *** is also the key consideration for the coming international events such as the Winter Olympic games,which could generate uncontrolled ecosystem issues not previously *** Yin Mountains in Chongli district,zha.gjiakou City,Hebei Province,China will be the core area of the 2022 Winter Olympic *** hypothesize that disturbances will be caused,therefore,the previous relationships between the habitat factors and plant community and the main environmental limiting factors before hosting them must be assessed to design future restoration ***,we used the two-way indicator species analysis(TWINSPAN)and market basket analysis(MBA)for vegetation classification in 91 sampling *** community and relationships among environmental variables(altitude,slope position,aspect,direction,inclination,soil porosity,soil bulk density,organic matter content and soil pH)were investigated through the trend correspondence(DCA)and canonical correspondence analyses(CCA).Also,the TWINSPAN was used to classify the vegetation into 6 different *** analysis showed that i)the spatial variation of soil moisture and the content of soil organic matter are the main factors limiting the development of shrub and herb communities;ii)the distribution of different forest communities was mainly affected by terrain factors(altitude,aspect and slope position);iii)the dynamic changes of vegetation communities in different altitudes were affected by the fluctuation of environmental factors and human disturbance,and the shrubs and herbaceous plants in mid-to-high altitude areas(above 1400 m)generally show the process o

关键词： Vegetation classification Topographic factors Community distribution Winter Olympic games

Research on Embedding Capacity and Efficiency of Information Hiding Based on Digital Images

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International Journal of Intelligence Science 2013年第2期3卷 77-85页

作者： Yanping zha.g Juan Jiang Yongliang zha heng zha.g Shu zhao School of Computer Science and Technology Anhui University Hefei China

generally speaking, being an efficient information hiding scheme, what we want to achieve is high embedding capacity of the cover image and high visual quality of the stego image, high visual quality is also called embedding efficiency. This paper mainly studies on the information hiding technology based on gray-scale digital images and especially considers the improvement of embedding capacity and embedding efficiency. For the purpose of that, two algorithms for information hiding were proposed, one is called high capacity of information hiding algorithm (HCIH for short), which achieves high embedding rate, and the other is called high quality of information hiding algorithm (HQIH for short), which realizes high embedding efficiency. The simulation experiments show that our proposed algorithms achieve better performance.

关键词： Information Hiding Embedding Capacity Embedding Efficiency Security Peak-Signal-to-Noise-Rate(PSNR)

Fabrication of High-Quality Niobium Superconducting Tunnel Junctions

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Chinese Physics Letters 2011年第8期28卷 289-292页

作者： XU Qin-Yin CAO Chun-Hai LI Meng-Yue JIANg Yi zha Shi-Tong KANg Lin XU Wei-Wei CHEN Jian WU Pei-heng Research Institute of Superconductor Electronics(RISE) Nanjing UniversityNanjing 210093

For high-quality superconducting tunnel junctions(STJs),it is necessary to reduce leakage current as much as *** describe the fabrication of niobium STJs using the selective niobium(Nb)etching process and various ways to minimize the leakage *** experiment shows that the leakage current mainly comes from shorts in the tunnel barrier layer rather than those around the junction *** systematic analysis of the thin film stress,surface morphology and modified junction structures,we fabricate high-quality Nb STJs with a gap voltage of 2.8 mV and a leakage current at 1 mV as low as 8.1%and 0.023%at 4.2 K and 0.3 K,respectively.

关键词： leakage tunnel film

In-Situ SRPES Study on the Band Alignment of (0001)CdS/CdTe Heterojunction

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Chinese Physics Letters 2012年第5期29卷 201-204页

作者： gAO Jun-Ning JIE Wan-Qi YUAN Yan-Yan zha.gang-Qiang XU Ling-Yan WU heng WANg Ya-Bin YU Hui ZHU Jun-Fa State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029

The band alignment of a (0001)CdS/CdTe heterojunction is in situ studied by synchrotron radiation photoemission spectroscopy (SRPES).The heterojunction is formed through stepwise deposition of a CdTe film on a wurtzite (0001)CdS single crystalline substrate via molecular beam *** shows an upward band bending of 0.55 eV,the valence band offset △Ev is calculated to be 0.65 e V and the conduction band offset △ Ec is 0.31 *** interracial band alignment is sketched to display type-Ⅰ band alignment.

关键词： alignment sketch bending

Individual and joint effects of borderline ankle-brachial index and high plasma total homocysteine on all-cause death in hypertensive adults

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Journal of geriatric Cardiology 2022年第7期19卷 522-530页

作者： Jun-Pei LI Tian-Yu CAO Xiao-Yuan zha Yun YU Zi-heng TAN Zai-Hua Cheng Hua-Bo YINg Wei ZHOU Lin-Juan ZHU Tao WANg Li-Shun LIU Hui-Hui BAO Xiao HUANg Xiao-Shu Cheng Department of Cardiology the Second Affiliated Hospital of Nanchang UniversityNanchangChina University of California Santa BarbaraCAUSA Rancheng Community Health Service Center WuyuanChina Center for Prevention and Treatment of Cardiovascular Diseases the Second Affiliated Hospital of Nanchang UniversityNan-changChina graduate School at Shenzhen Tsinghua UniversityShenzhenChina

BACKgROUND The cardiovascular hazards of total homocysteine(tHcy)are long *** addition,despite the acknow-ledgment on the importance of low ankle-brachial index(ABI)(<0.9),borderline ABI(0.91-0.99)was once commonly **... 详细信息

BACKgROUND The cardiovascular hazards of total homocysteine(tHcy)are long *** addition,despite the acknow-ledgment on the importance of low ankle-brachial index(ABI)(gistry *** was described into two groups:normal ABI(1.00-1.40)and borderline *** level was also divided into two groups:groups were analyzed,using COX proportional hazard regression model,separately and pairwise to observe the independ-ent and joint effect on all-cause *** A total of 126(1.2%)deaths were observed in the 1.7 years follow-up *** ABI has a higher predicted risk of death than normal ABI(HR=1.87,95%CI:1.17-3.00)after adjusting for potential *** with tHcy levelgh tHcy)had higher risk to event outcome(HR=1.99,95%CI:1.30-3.05).According to the cumulative hazard curve,group with borderline ABI and high tHcy level has significantly higher altitude and larger increasing rate over follow-up period compare to other *** those with borderline ABI,participants with high tHcy had higher death risk than those with low tHcy,nevertheless,no significant different between borderline and normal ABI among those with low tHcy *** Borderline ABI and tHcy level both have independent predictive value on all-cause *** combined group of borderline ABI and high tHcy has highest risk factor of outcomes,which suggested the mutual additive value of border-line ABI and *** attention should be given to the importance of borderline ABI in hypertensive population,especially with elevated tHcy level.

关键词： hypertensive death ankle

Theoretical analysis and experimental verification of thermal decomposition mechanism of CuSe

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Transactions of Nonferrous Metals Society of China 2022年第10期32卷 3478-3486页

作者： Huan LUO heng XIONg Wen-long JIANg Lang LIU guo-zheng zha Tian-tian ZHEN Bin YANg Bao-qiang XU National Engineering Research Center of Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Yunnan Provincial Key Laboratory for Nonferrous Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Non-Ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China

Experiments on the thermal decomposition of CuSe were carried out by using a thermogravimetric analyzer(TgA)at different heating *** kinetic parameters and mechanisms were discussed based on model-free and model-based *** decomposition rate and decomposition behavior of CuSe were investigated by using a vacuum thermogravimetric *** results showed that the R3 model was identified as the most probable mechanism function under the present experimental *** average values of activation energy and the pre-exponential factor were 12.344 J/mol and 0.152 s^(−1),*** actual decomposition rate of CuSe was found to be 0.0030 g/(cm^(2)·min).

关键词： CuSe thermal decomposition non-isothermal kinetics mechanism

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中国东部油气区的资源潜力

石油学报 2003年第5期24卷 1-3,9页

作者：查全衡何文渊中国石油天然气集团公司咨询中心北京100724

东部油气区是中国最重要的石油生产基地。经过 40多年的勘探开发后 ,其生产潜力是一个备受关注的问题。对东部油气区钻探程度、储量年增长曲线、储量发现率曲线和资源探明率 4项指标进行了分析 ,充分考虑了本区实际存在的勘探目标和资... 详细信息

东部油气区是中国最重要的石油生产基地。经过 40多年的勘探开发后 ,其生产潜力是一个备受关注的问题。对东部油气区钻探程度、储量年增长曲线、储量发现率曲线和资源探明率 4项指标进行了分析 ,充分考虑了本区实际存在的勘探目标和资源潜力 ,初步提出了适合我国国情的勘探分期标准。依据 4项指标将本区勘探领域分为老区生产层系和新区与老区新层系两大类。研究结果表明 ,前一类处于勘探中期 ,储量可以持续稳定增长 ;后一类处于勘探早期。

关键词：中国东部油气区资源潜力勘探目标勘探阶段分期指标