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Search Results: 1 - 10 of 325185 matches for " 罗　菲<br>ZHANG Hongqi "
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蛇菰内生菌Aspergillus sp. SHG-7 代谢产物研究
Study on secondary metabolites from endophytic fungus Aspergillus sp. SHG-7 isolated from Balanophora henryi Hesml
张宏岐,柳　蔚,高星星,郑倩倩,罗　菲<br>ZHANG Hongqi,LIU Wei,GAO Xingxing,ZHEN Qianqian,LUO Fei
- , 2018,
Abstract: 从药用植物宜昌蛇菰(Balanophora henryi Hesml.)中分离得到一株内生真菌Aspergillus sp. SHG-7，通过固体发酵，乙酸乙酯萃取得浸膏，其浸膏经硅胶柱层析、Sephadex LH-20、半制备型HPLC等分离手段分离得到6个化合物，经核磁共振、质谱等手段鉴定其结构分别为灰黄霉素(1)，麦角甾醇(2)，麦角甾-7， 22-二烯-3， 6-二酮(3)，麦角甾-7， 22-二烯-3， 5， 6-三醇(4)，软脂酸-1-甘油酯(5)，肉豆蔻酸(6).化合物1对MCF-7、A549及Hela细胞具有一定的细胞毒活性，IC50分别为18.36 ± 2.32 μM、26.58 ± 1.62 μM 和74.29 ± 1.34 μM，化合物2～化合物6对以上肿瘤细胞无明显活性.
Research on a case-based reasoning method using cost-sensitive learner and its applications
一种基于代价敏感学习的范例推理方法及其应用研究
LUO Fei-fei,LIU Gui-quan,AN Jing-qi,ZHANG Ting-hui,<br>罗菲菲,刘贵全,安景琦,等
计算机应用 , 2005,
Abstract: This paper proposed a case-based reasoning method using cost-sensitive learning that can classify and forecast large-scale and high dimension data. While classifying, this method adjust attribute weight constantly, in order to reduce the misclassification cost. The method has made a better result on some intrusion detection research.
Kinetics of photocatalytic degradation of humic acid by nano-TiO2 loaded on granular activated carbon
活性炭负载纳米TiO2对腐殖酸光催化降解动力学
LIU Huanhuan,KE Yujuan,CHEN Quanyuan,ZHANG Lina,LUO Zhou,WANG Lu,DU Feifei,<br>柳欢欢,柯玉娟,陈泉源,张立娜,罗周,王璐,杜菲菲
环境科学学报 , 2009,
Abstract: A nano-TiO2/activated carbon composite photocatalyst was prepared by loading nano-TiO2 on the surfaces of granular activated carbon by a sol-gel method. The catalyst was then applied to the photocatalytic degradation of humic acid (HA). The kinetics of HA degradation can be expressed by the Langmuir-Hinshelwood (L-H) equation. The reaction rate constant KLH was 0.1124 mg·L-1·min-1, and the superficial adsorption equilibrium constant K* was 0.3402 L·mg-1. The photocatalytic degradation of humic acid by the nano-TiO2/activated carbon composite photocatalyst exhibited a synergetic effect. The adsorption of granular activated carbon greatly enhanced the photocatalysis of humic acid.
Effects of Land Use and Topographic Factors on the Variability of Soil Nutrients in Newly Reclaimed Area in Yili
伊犁新垦区土地利用和地形对表层土壤养分变异性的影响
LIU Fang,ZHANG Hongqi,<br>刘芳,张红旗
资源科学 , 2012,
Abstract: The spatial variability of soil nutrient may be influenced by environmental factors. Based on the data of measured section in the field and laboratory analysis, this study has explored the effects of land use and topographic factors on the distribution characteristics of surface soil nutrients on the scale of sampling points with the mathematical statistics method. The results show that: 1) Land use types have significant effects on the organic matter, total nitrogen and total phosphorus of the surface soil but have slight effects on total potassium. Saline land contains the most organic matters while sand contains the least. Total nitrogen in wasteland is less than that in farmland. As for the total phosphorus, saline land has the highest average content and moderate coverage grassland has the largest coefficient of variation; 2) Different topographic factors affect the soil nutrients to different degrees. The four soil nutrients are positively correlated with altitude, they have the lowest average content at the altitude gradient of 500～600m and the largest fluctuation range at the altitude gradient of 600～700m. The average content of organic matter, total nitrogen and total potassium at high altitude gradient is higher than that at low altitude gradient. Nevertheless, the average content of total phosphorus presents inverted-U distribution with the rise of the altitude; 3) Organic matter and total nitrogen included in the soil are positively correlated with slope. The average content of them above the slope of 3° is obviously higher than that under the slope of 3°. When the slope gradient is less than 1.82°, the average content of the four soil nutrients shows the largest fluctuation range. 4) Total phosphorus is negatively correlated with the slope direction. The average content of the soil nutrients on the shady slope is higher than that on the sunny slope. However, except total potassium, the other three soil nutrients have larger fluctuation ranges on the sunny slope than they do on the shady slope; 5) The interaction between land use types and topographical factors has effect on the nutrients content of surface soil. Soil organic matter content of moderate coverage grassland is obviously higher than that of farmland and low coverage grassland at places with higher altitude, sharper slope and shady slope, but it is the opposite at places with lower altitude, gentler slope and sunny slope.
Spatial Difference of Agricultural Productivity in China at County Level
基于县域单元的中国农业生产率空间分异规律研究
YANG Yang,ZHANG Hongqi,<br>杨阳,张红旗
资源科学 , 2009,
Abstract: With the support of Geographic Information System (GIS), we aim to present and analyze spatial difference of agricultural productivity in China at county level in this paper. First, we calculate agricultural land productivity, which is composed of two indicators, by using data of 2014 counties, including grain production, labor, agricultural added value and so on. By employing GIS, spatial attributes are applied to agricultural labor productivity, which indicates that every county possesses two unique indicators. Based on previously constructed database, we integrate two indicators into agricultural labor productivity, which are sorted into three categories by their value and simultaneously display and map the spatial distribution within the GIS system. Furthermore, these differences are analyzed with specific data on agricultural input, such as mechanical power and fertilizer. Similarly, we calculate agricultural land productivity at county level, divide them into three categories and obtain the spatial difference in China. The results indicate that the spatial difference of agriculture productivity in China is distinct. There are 229 counties with high agricultural labor productivity, which are mainly located in Sanjiang plain, the piedmont plain of Yanshan and Taihang Mountain, Jiaodong Peninsula, Hebei-Shandong-Henan lower plain, Dongtinghu plain, eastern part of Jianghuai plain, western part of Fujian province, and most part of Xinjiang. The high agricultural labor productivity is due to high agricultural mechanization, as well as high level of multiple-cropping index. There are 201 counties with low agricultural labor productivity, which are distributed in Losses plateau, Sichuan and Yunnan plateau, Qingling and Daba mountain area, Inner Magnolia and the area long the Great Wall, southern part of Guangdong, Western part of Yunnan, and southern part of Tibet. It can be indicated from the results that China should enhance agricultural investment in these areas to change the poor agricultural resource and low agricultural input. The number of counties with high agricultural land productivity is 197, most of which are located in Jiang-Han plain, Dongtinghu plain, Poyanghu plain, Su-Wan plain, and Yangtze River delta, where level of agricultural input is high and cropping structure decides the high productivity. By contrast, 277 counties with low agricultural land productivity are clustered in western part of Songnen plain, Sanjiang plain, eastern part of Inner Magnolia, Losses plateau, Qingling and Daba mountain area, Sichuan and Yunnan plateau. In these areas, low land productivity is accompanied by poor agricultural facilities and low agricultural input.
Land Use Structure and Temporal-Spatial Variation Analysis in Eight Main Agricultural Regions in China
中国八个重要农业区土地利用结构及时空变化分析
LIU Fang,ZHANG Hongqi,<br>刘芳,张红旗
资源科学 , 2011,
Abstract: 本文对我国8个重要农业区1980s末至2005年间土地利用结构及其时空变化进行研究。结果表明：①我国耕地和城乡工矿及居民用地集中分布在黄淮海平原、长江中游及江淮地区、四川盆地和松嫩平原，草地、林地和未利用地则积聚在新疆、内蒙古东部区和华南蔗果区；②1980s末至2005年间8区耕地总量上升，其中内蒙古东部区、新疆和三江平原增量显著，长江中游平原及江淮地区、四川盆地和黄淮海平原减少，耕地空间重心由我国东部、中部复种指数较高的传统农业核心区向西北、东北等复种指数较低且生态相对脆弱地区迁移，整体土地生产能力有所下降；③各区草地面积皆下降，其中内蒙古东部区和新疆为减量主体；各区城乡工矿及居民用地面积快速上升，其中黄淮海平原和松嫩平原面积增量占8区总增量的70%；林地面积总体增加，其中内蒙古东部区占8区林地净增总量的90%，而三江平原和黄淮海平原林地略降；④未利用地面积总体增加，增量主要分布在内蒙古东部区、新疆和松嫩平原，构成多为沙地、裸土地和盐碱地，表明局部地区存在土地退化现象；黄淮海平原、长江中游及江淮地区和四川盆地因工业化、城市化进程加快导致未利用地进一步减少，后备土地资源日趋紧张。
Assessment of Limiting Factors of Undeveloped Agricultural Land over Newly Reclaimed Areas in Yili, Xinjiang
伊犁新垦区未开发农业土地资源限制性因素评价
ZHANG Hongqi,YANG Yang,<br>张红旗,杨 阳
资源科学 , 2009,
Abstract: The Yili River watershed is considered a potential area for agricultural development with desirable land and water resources. Recently the Ministry of Land and Resource of China has initiated national land consolidation and rehabilitation projects, for which the newly reclaimed area in Yili, Xinjiang Uygur Autonomous Region, was selected. However, due to continued development in the past, a majority of the land has been converted into arable land, leading undeveloped land to bear certain characteristics, like relatively thin soil, steep slope, low soil fertility, and sandy texture. If irrational development modes continued, it would inevitably cause a series of eco-environmental problems, such as soil erosion, land desertification and salinization. Therefore, it is particularly urgent to assess different types of constraints associated with agricultural land resources as well as to investigate their spatial distributions for providing meaningful reference for optimal allocation of crops and eventually realizing sustainable development over the study area. Based on GIS, RS and GPS techniques and field investigations , the authors examined in detail current agricultural land resources over newly reclaimed areas in Yili, quantitatively evaluated its limiting factors, i.e., the type, level and spatial distribution, and explored its future scenarios within a framework of sustainable development. Results indicated that the potential area for development is around 29.05×104 hm2 over the study area, with showing poor quality and 55.86% area of land primarily constrained by severe level limiting factors. It was suggested that future agricultural development of this newly reclaimed area consist of agriculture and husbandry. The dominant limiting factors of Nan-an canal irrigation region are soil depth and gully density. Over the area with thin soil and dense gully, it is proper to grow perennial grass and feed, while over high quality land, early ripening of cotton, wheat, maize and sugar beet would be good choices. It was found that in the Yili River northern irrigation, the dominant factors are dune, soil texture and soil organic where grapes, corns, lavender and fruits could be planted. However, over the dense dune area, the current land use should be converted back into pasture land or bushes. In the Chabuchaer Yili River irrigation region, the dominant limiting factors are ground water, drainage and salinization. Therefore proper development of rice and alfalfa could be a good way to prevent and mitigate salinization. In the Tuan-jie irrigation region and Yue-jing irrigation region, the dominant factors are groundwater and drainage. Over the area along the Nan-an Ditch, grains and economic crops could be planted. However, it was indicated that wetland here should be protected and reclamation should be forbidden.
Analysis of Land Use and Land Cover Change in the Yili Newly Reclaimed Area in Recent 20 Years
近20年来伊犁新垦区土地利用/覆被变化分析
YANG Yang,ZHANG Hongqi,<br>杨 阳,张红旗
资源科学 , 2009,
Abstract: The Yili newly reclaimed area is located in the Yili River valley, which is a main distribution area for undeveloped agricultural land in western China. Therefore, it is considered a potential area with suitable land and water resources for agricultural development, where a land consolidation and rehabilitation project supported by the Ministry of Land and Resource of China is carried out. However, due to the rapid expansion of agricultural land reclamation during past years, the land use and land cover here has been changed dramatically, resulting in a series of environment problems, such as soil erosion, land desertification and salinization. In order to provide meaningful reference for optimal land use allocation as well as environmental protection, the authors examined spatial and temporal patterns of land use over the Yili newly reclaimed area from 1985 to 2008, and further explored the major changing land use types and their transfer between each other. Remote sensing imagery, land use maps and fieldwork data were utilized in this study. Results show that from 1985 to 2008, arable land increased to 4.99×104hm2, with an increase in area percentage from 38% to 57% over the area, the largest increased amount compared with other land cover types. Unused land increased to 1.07×104hm2 in the same period, the land cover type with the second largest increase amount. It was found that among the unused land, the sandy land increased from 2.86×104 hm2 to 2.95×104hm2, and the saline-alkali land increased from 0.21×104 hm2 to 1.56×104 hm2, respectively, while marsh land deceased from 1.2×104hm2 to 0.83× 104 hm2. Water bodies, woodland and land for construction were showing increasing trend. The land use type with the most decreasing trend was grassland. It decreased to 7.02×104hm2, and is now just contributing 36% area of the study area, while contributing 49% in the year 1985. The transfer pattern among land use types during last 23 years were shown to be dramatic. The grassland is the main source for increases in other land use types. It was also found that the arable land is the land use type with the largest increasing area in the Yili newly reclaimed area, following by the land for construction. Increased sandy land primarily resulted from decreases in grassland and arable land while increased saline-alkali land was basically transferred from marsh, grassland and arable land. It was indicated that at some land use level agricultural land reclamation was the most influencing factor driving the land use change over the Yili newly reclaimed area. Thus, these changes leaded to some negative impacts on the environment. The increase in saline-alkali land and the decrease in marsh essentially reflected environment deterioration caused by an irrational development way.
Assessment of the Land Desertification Sensitivity of Newly Reclaimed Area in Yili,Xinjiang
新疆伊犁新垦区土地荒漠化敏感性评价
KANG Lei,ZHANG Hongqi,<br>康蕾,张红旗
资源科学 , 2012,
Abstract: Xinjiang,located in the northwestern border of China,is the largest area of land desertification in China and also affected most by sand.In this study,based on field investigations,we have built an evaluation index system of land desertification sensitivity of Xinjiang Newly reclaimed area with the information of soil texture,soil organic matter content,groundwater,dune,gully density and sand transfer and change,saline expansion rate and grass reduce rate.According to the evaluation index system,we completed the comprehensive assessment of land desertification sensitivity in the study area with the supports of proper assessment units and GIS.The research results show that:the types of land desertification sensitivity are various in Xinjiang Newly reclaimed area,including the sensitivity of soil erosion,sandy desertification and land salinization;more than 70%of the land show varying degrees of desertification sensitivity,with mildly sensitive desertified land accounting for more than half of the total land area,moderately sensitive and highly sensitive desertified land making up 14.31%and 6.90%respectively.These data indicate that the overall ecological environment of newly reclaimed area is relatively fragile so that land desertification is easy to happen during the land development and utilization.From the points of view of spatial distribution and types of desertification sensitivity,Nan’an Canal Irrigated Area is mainly affected by the water erosion desertification,with nearly 80%of the land showing land desertification sensitivity and highly sensitive desertified land accounting for more than 10%.North Riverside Irrigated Area of the Yili River is a region of the strongest sandy desertification sensitivity,with more than 70%of the land threatened by desertification.Chabuchar Irrigated Area and Tuanjie Irrigated Area are mainly affected by secondary salinization,with over 60%of mild-sensitive land.58.28%of the land in Yuejin Irrigated Area is free of desertification sensitivity and the area is mainly distributed by mildly sensitive desertified land,so the environment there is relatively good.Therefore,improving the irrigation and drainage system and preventing the secondary soil salinization are the key points in future land resources development of the last three irrigated areas.
Design and Implementation of the Agricultural LandUse Optimal Allocation System
农业土地利用优化配置系统的研建
ZHANG Ying,ZHANG Hongqi,NI Dongying,<br>张 英,张红旗,倪东英
资源科学 , 2009,
Abstract: 本文依据农业土地利用优化配置的基本技术流程，基于.NET 2005平台、C#语言和ArcGIS Engine 9.2组件，设计开发了具有统一用户界面和运行环境，包括数据预处理、土地适宜性评价、面积最优计算、空间配置和结果输出等五大功能模块的农业土地利用优化配置系统（ALUOA）。ALUOA系统的突出贡献是将土地适宜性评价、土地利用结构优化和空间配置三大过程有机整合，实现了功能模块之间特别是GIS与优化模型间的有效联接。以伊犁新垦区为案例进行系统验证研究的结果表明：ALUOA操作界面简单，交互性良好，方便用户参与研究、决策过程；具有较强的空间、属性数据分析、决策推理和信息可视化能力。可为区域农业土地利用优化配置研究提供更为全面、规范和自动化的服务。
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