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2001—2019年湖南省叶面积指数时空变化动态研究

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测绘与空间地理信息 2024年第4期47卷 69-72,76页

作者：唐欲然郑文武龙岳红衡阳师范学院地理与旅游学院湖南衡阳421010 湖南城市学院市政与测绘工程学院湖南益阳413000

基于MODIS叶面积指数时序数据集,运用变异系数、Mann-Kendall趋势检验和相关分析等主要方法,对2001—2019年湖南省植被时空特征、变化趋势及其与气象因子的对应关系进行了研究。结果表明:1)湖南省叶面积指数保持在较高值,整体植被LAI呈... 详细信息

基于MODIS叶面积指数时序数据集,运用变异系数、Mann-Kendall趋势检验和相关分析等主要方法,对2001—2019年湖南省植被时空特征、变化趋势及其与气象因子的对应关系进行了研究。结果表明:1)湖南省叶面积指数保持在较高值,整体植被LAI呈增加趋势,速率为0.57%/10a;西部植被生长好于东部,高植被生长区及中高植被生长区占整个省域面积的80.5%;2)省内植被LAI与气象关系不显著,且与降水、气温呈正相关,与日照时数呈负相关。

关键词：时空动态典型植被气象因素叶面积指数湖南省

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橄榄仁抗氧化肽的分离鉴定及分子对接

食品与发酵工业 2024年第5期50卷 189-198页

作者：张迎阳董亚云邹平郑文武常州大学药学院/生物与食品工程学院江苏常州213164

该研究利用酶解法结合凝胶色谱柱从橄榄仁中分离纯化得到6个抗氧化肽,采用分子对接模拟6种抗氧化肽与超氧化物歧化酶(superoxide dismutase, SOD)的结合机制。采用酶解法从橄榄仁中提取抗氧化活性肽,以水解度、DPPH自由基清除率为指标,... 详细信息

该研究利用酶解法结合凝胶色谱柱从橄榄仁中分离纯化得到6个抗氧化肽,采用分子对接模拟6种抗氧化肽与超氧化物歧化酶(superoxide dismutase, SOD)的结合机制。采用酶解法从橄榄仁中提取抗氧化活性肽,以水解度、DPPH自由基清除率为指标,从6种商用酶中筛选出最适蛋白酶为木瓜蛋白酶,以底物浓度、酶底比、酶解时间、温度进行单因素试验,选取影响酶解反应的3个因素(酶底比>温度>时间)进行响应面法优化得出最佳工艺条件为底物质量浓度50 g/L、酶底比为3.3%(质量分数)、温度20℃、时间88 min。对最优条件下的粗肽液进行SephadexG-25和SephadexG-15分离纯化得到6个具有良好活性的抗氧化肽,分别为WLSF、TSVLR、LVYLVR、AGGKPFQ、YYPFKGFA、AFNVDERLAR。TSVLR显示出最高的DPPH自由基清除活性81.07%和羟自由基清除能力42.48%。分子对接研究表明,纯化的肽通过疏水效应和氢键与抗氧化相关的关键蛋白SOD有效结合。结果表明,橄榄仁可作为天然食物来源制取功能性食品的一个新的探究方向。

关键词：橄榄仁抗氧化肽响应面优化分离鉴定分子对接

Comprehensive optimization of piezoelectric coefficient and depolarization temperature in Mn-doped Bi_(0.5)Na_(0.5)TiO_(3)-Bi_(0.5)K_(0.5)TiO_(3)-BaTiO_(3)lead-free piezoceramics

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Journal of Materials Science & Technology 2024年第5期172卷 255-263页

作者： Huashan zheng Enwei Sun Huajie Luo Xiaoyu Zhang Yixiao Yang Bin Yang Rui Zhang Shantao Zhang wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania16802United States of America

Lead-free Bi_(_(0.5))Na_(_(0.5))TiO_(3)(BNT)piezoelectric ceramics have the advantages of large coercive fields and high Curie *** the improvement of piezoelectric coefficient(d 33)is usually accompanied by a huge sacrifice of depolarization temperature(T d).In this work,a well-balanced performance of d 33 and T d is achieved in MnO_(2)-doped 0.79(Bi_(_(0.5))Na_(_(0.5))TiO_(3))-0.14(Bi_(0.5)K_(0.5)TiO_(3))-0.07BaTiO_(3)ternary *** in-corporation of 0.25 mol%MnO_(2)enhances the d 33 by more than 40%,while T d remains almost unchanged(i.e.,d 33=181 pC/N,T d=184℃).X-ray diffraction(XRD)shows that an appropriate fraction of the small axis-ratio ferroelectric phase(pseudo-cubic,P c)coexists with the long-range ferroelectric phase(tetrag-onal,T)under this MnO_(2)*** force microscopy(PFM)has revealed a special domain configuration,namely large striped and layered macro domains embedded with small *** study provides a distinctive avenue to design BNT-based piezoelectric ceramics with high piezoelectric performance and temperature stability.

关键词： BNT-BKT-BT ceramics Mn doping Piezoelectric Depolarization temperature Phase structure

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历史文化村镇数字化保护与应用

国土资源导刊 2024年第1期21卷 34-42页

作者：杨立国宁旺芬刘沛林邓运员胡最郑文武李伯华衡阳师范学院地理与旅游学院湖南衡阳421002 古村古镇文化遗产数字化传承湖南省协同创新中心湖南衡阳421002

数字技术越来越广泛应用于文化遗产的保护与发展,为历史文化村镇的保护与利用提供了新途径。针对历史文化村镇创新性保护和发展的新需求,本文将数字技术赋能于历史文化村镇的保护与开发,阐释了历史文化村镇数字化保护的基本概念,构建历... 详细信息

数字技术越来越广泛应用于文化遗产的保护与发展,为历史文化村镇的保护与利用提供了新途径。针对历史文化村镇创新性保护和发展的新需求,本文将数字技术赋能于历史文化村镇的保护与开发,阐释了历史文化村镇数字化保护的基本概念,构建历史文化村镇数字化保护的理论体系,全面总结了历史文化村镇的数字化方法和数字化内容在多领域的具体应用。具体而言:景观基因信息、景观基因图谱和地图符号等为历史文化村镇的数字化保护与应用提供了强有力的理论支撑;通过多样的数字技术可以对历史文化村镇信息进行全方位记录和永久性保存,并对采集和记录的信息进行数字化展示与传播;在历史文化村镇数字化应用上,其数字化内容能够为城乡规划和智慧管理提供有效指导,与多元产业融合实现产业化拓展和延伸。总之,数字技术为历史文化村镇的文化保护和传承提供了无限的活力与动力,需要持续推进历史文化村镇的数字化转型,丰富中国乡村地理数字化的理论研究。

关键词：历史文化村镇数字化保护数字化应用

Study on Plugging Technology in Oil Test

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Open Journal of Yangtze Oil and Gas 2022年第4期7卷 240-252页

作者： Xiong Wang Lejun Liao Ru Bai Fu Liu wenwu zheng Song Wang College of Chemistry and Environmental Engineering Yangtze University Jingzhou China Xianyang Chuanqing Xinyuan Co. Ltd Xianyang China Sinopec North China Petroleum Engineering Co. Ltd Zhengzhou China

In view of the shortcomings of poor temperature resistance, poor pumpability and poor pressure-bearing capacity of commonly used gel plugging materials, polyacrylamide (HPAM) and N,N-methylene bisacrylamide (BIS) were selected for crosslinking and compounding to make a new type of gel plugging material with high temperature and pressure resistance. The compressive strength and yield stress were measured by inverted observation method to evaluate the gel strength. The anti-temperature, anti-pressure, anti-dilution and gel-breaking properties of the gel were evaluated. Finally, 71 type high temperature and high pressure water loss instrument and high temperature and high pressure filter with slit plate were used to evaluate the plugging capacity of gel plugging agent. The experimental results show that the new gel plugging system between 100°C - 120°C, gelation time can be controlled at about 5 h;it has strong temperature resistance, compression resistance, dilution resistance and gel breaking performance. In the face of permeability and fracture leakage simulation experiments, when the ambient temperature below 120°C, pressure within 5 MPa, the filter loss of gel plugging agent is far less than the market two conventional plugging agent, has excellent plugging performance.

关键词： Changqing Oilfield Leakage New Gel Plugging Agent Gel Strength Temperature and Salt Resistance Plugging Performance

Progress toward the sustainable development of world cultural heritage sites facing land-cover changes

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The Innovation 2023年第5期4卷 87-95页

作者： Huadong Guo Fulong Chen Yunwei Tang Yanbin Ding Min Chen Wei Zhou Meng Zhu Sheng Gao Ruixia Yang wenwu zheng Chaoyang Fang Hui Lin Ana Pereira Roders Francesca Cigna Deodato Tapete Bing Xu International Research Center of Big Data for Sustainable Development Goals Beijing 100094China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijng 100094China International Centre on Space Technologies for Natural and Cultural Heritage Under the Auspices of UNESCO Beijing 100094China Cooperative Innovation Center for Digitalization of Cultural Heritage in Traditional Vllages and Towns Hengyang Normal UniversityHengyang 421010China School of Geography Nanjing Normal UniversityNanjing 210023China Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education&School of Geography and EnvironmentJiangxi Normal UniversityNanchang 330022China Faculty of Architecture and the Built Environment Delft University of Technology2600 AA Delftthe Netherlands Instiute of Atmospheric Sciences and Climate(SAC) National Research Council(CNR)Via del Fosso del Cavaliere 10000133 RomeItaly Italian Space Agency(ASI) Via del Politecnico snc00133 RomeItaly Department of Earth System Science Tsinghua UniversityBeijing 100084China

The quantification of the extent and dynamics of land-use changes is a key metric employed to assess the progress toward several Sustainable Development Goals(SDGs)that form part of the United Nations 2030 Sustainable Development *** terms of anthropogenic factors threatening the conservation of heritage properties,such a metric aids in the assessment of achievements toward heritage sustainability solving the problem of insufficient data ***,in this study,589 cultural World Heritage List(WHL)properties from 115 countries were analyzed,encompassing globally distributed and statistically significant samples of“monuments and groups of buildings”(73.2%),“sites”(19.3%),and“cultural landscapes”(7.5%).Land-cover changes in the WHL properties between 2015 and 2020 were automatically extracted from big data collections of high-resolution satellite imagery accessed via Google Earth Engine using intelligent remote sensing *** indexes(SIs)were estimated for the protection zones of each property,and the results were employed,for the first time,to assess the progress of each country toward SDG Target *** the apparent advances in SIs(10.4%),most countries either exhibited steady(20.0%)or declining(69.6%)SIs due to limited cultural investigations and enhanced negative anthropogenic *** study confirms that land-cover changes are among serious threats for heritage conservation,with heritage in some countries wherein the need to address this threat is most crucial,and the proposed spatiotemporal monitoring approach is recommended.

关键词： landscape heritage Engine

Study on a Polyamine-Based Anti-Collapse Drilling Fluid System

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Open Journal of Yangtze Oil and Gas 2022年第3期7卷 203-212页

作者： wenwu zheng Fu Liu Jing Han Binbin He Shunyuan Zhang Qichao Cao Xiong Wang Xintong Li Sinopec Group North China Petroleum Engineering Co Ltd. Zhengzhou China Overseas Institute of China Petroleum Corporation Engineering Technology Research Institute Beijing China Yangtze University Jingzhou China

In complex strata, oil-based drilling fluid is the preferred drilling fluid system, but its preparation cost is high, and there are hidden safety risks. Therefore, the new progress of high-performance anti-collapse water-based drilling fluid at home and abroad is analyzed. It is difficult to prevent and control the well collapse. Once the well wall instability problem occurs, it will often bring huge economic losses to the enterprises, and the underground safety accidents will occur. In order to ensure the stability of the well wall and improve the downhole safety, the key treatment agent of water-based collapse drilling fluid is selected, the anti-collapse drilling fluid system is formulated, the evaluation method of drilling fluid prevention performance is established, and a set of water-based drilling fluid system suitable for easy to collapse strata in China is selected to ensure the downhole safety. The development trend of high performance anti-collapse water-based drilling fluid is expected to provide a reference for the research of high performance anti-collapse water-based drilling fluid system and key treatment agent.

关键词： Well Wall Stability Anti-Collapse Water-Based Drilling Fluid Evaluation Method High Temperature Resistance Salt Resistance

Isolation, Purification, and Identification of a Novel HX-Producing Strain and Optimization of Its Fermentation Medium

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Food and Nutrition Sciences 2018年第5期9卷 447-463页

作者： zhengkai Xue wenwu zheng School of White Liquor Luzhou Vocational and Technical College Luzhou China Department of Cardiology The Affiliated Hospital of Southwest Medical University Luzhou China

Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol.

关键词： Isolation Identification Hexanoic Acid-Producing Strain Fermentation Medium Optimization

UAV Laser scanning technology:a potential cost-effective tool for micro-topography detection over wooded areas for archaeological prospection

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International Journal of Digital Earth 2020年第11期13卷 1279-1301页

作者： Wei Zhou Fulong Chen Huadong Guo Mingyuan Hu Qi Li Panpan Tang wenwu zheng Jian’an Liu Rupeng Luo Kaikai Yan Ru Li Pilong Shi Sheng Nie Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China International Centre on Space Technologies for Natural and Cultural Heritage(HIST)Under the auspices of UNESCO BeijingPeople’s Republic of China Hengyang Base of International Centre on Space Technologies for Natural and Cultural Heritage under the auspices of UNESCO HengyangPeople’s Republic of China Institute of Space and Earth Information Science the Chinese University of Hong KongHong KongPeople’s Republic of China Airborne Remote Sensing Center Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China Zhejiang Provincial Institute of Cultural Relics and Archaeology HangzhouPeople’s Republic of China

Airborne laser scanning(ALS)has recently been identified as a potential tool in topographic mapping for archaeological ***,most existing applications in this field refers to manned ALS systems,for which the high operation and maintenance costs limits its application in small-scale archaeological *** this paper,we conducted an exploratory study on the application of the unmanned aerial vehicle(UAV)laser scanning(ULS)system in ancient micro-topography detection over wooded *** with manned ALS technology,we analyzed the advantages and potentials of ULS technology for archaeological *** we outlined existing mainstream survey-grade UAV-based laser scanners,data processing and visualization ***,we performed case studies in three cultural heritage sites in Zhejiang Province,China using two representative mainstream survey-grade ULS *** were then verified by an in-site ***,the correct selection of ULS devices,the planning of data acquisition missions and the use of appropriate data processing methods specifically for archaeological prospection were *** paper provides a cost-effective and flexible solution for micro-topography detection in wooded *** technology,as demonstrated here,can be an important supplement to existing archaeological investigation methods,particularly for small-scale areas,and has promising prospects in archaeological applications.

关键词： Unmanned aerial vehicle(UAV) light detection and ranging(LiDAR) archaeological prospection micro-topography mapping forest