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京津冀 5

D区 2

中国西北地区 2

拉压杆模型 2

生态环境 2

CDR 1

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京津冀地区；水安全；水资源高效利用；地下水位恢复；河湖生态保护 1

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Repeats in the transcribed regions: comprehensive characterization and comparison of

Manosh Kumar BISWAS, Christoph MAYER, Xiuxin DENG

《农业科学与工程前沿（英文）》 2017年 第4卷 第4期   页码 421-432 doi: 10.15302/J-FASE-2017160

摘要： A large number of expressed sequences tags are available for spp., which provides an opportunity to understand genomic organization of the transcribed regions. Here, we report a detailed analysis of repetitive elements including tandem repeats (TRs) and transposable elements (TEs) in the transcribed region of the spp. On average, 22% of the expressed sequence tags (ESTs) contain TRs. The relative density of TR classes is highly taxon-specific. For instance, has a high relative density of mononucleotide repeats, whereas dinucleotide repeats are rare. The proportions of 2–6, 7–30 and 31–50 bp repeats were almost identical in all studied species except for and . We found that<1% of the citrus ESTs have a similarity with transposable elements. Transcriptional activity of transposable element families varied even within the same class of elements. A high proportion of transcriptional activity was observed for -like TEs compare to other TE classes. While TEs are relatively rare, TRs are abundant elements in ESTs of citrus. The high proportion of TRs that have a unit size longer than 6 bp raises the question about a possible functional or evolutionary role of these elements.

关键词： Citrus spp.     tandem repeats     transcribed region     transposable elements    

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The comparative study of dwelling houses in the southwest multi-ethnic region, taking Fugong county for

Fang WANG, Jiaping LIU

《结构与土木工程前沿（英文）》 2010年 第4卷 第4期   页码 474-482 doi: 10.1007/s11709-010-0089-z

摘要： A number of ethnic minorities are being distributed in southwest China. Yunnan Province is an area inhabited by multi-ethnic groups. For a long time, the ethnic groups have been interacted by others in the cultural aspect, while retaining their own ethnic traditions. The performances of ethnic groups’ dwelling houses are similar as determined by natural and cultural elements of the same area. This paper mainly analyzes decisive factors behind similar appearances by the way of field research on two minorities, Nu ethnic group and Li-su ethnic group, in the Fugong county, Nujiang Li-su autonomous prefecture. Moreover, the paper tries to summarize the commonality and individuality of the minorities in order to provide useful theoretical reference for the minorities building of new socialist countryside in the future.

关键词： Nu ethnic group     Li-su ethnic group     mixed region     living culture     living mode     living acts    

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Protective roles of heat stress on the neurons in hippocampal CA1 region of mice

WANG Chunxu, WANG Hanxing

《医学前沿（英文）》 2007年 第1卷 第4期   页码 418-422 doi: 10.1007/s11684-007-0082-7

摘要： The effects of heat stress on the neurons in hippocampal CA1 region of brain ischemia/reperfusion were explored. The mice were pretreated with heat stress followed by ischemia/reperfusion by clipping bilateral cervical commo n arteries for 7 min. Mice were divided randomly into four groups as follows: (1) normal control group; (2) heat stress pretreated subsequent to ischemia/reperfusion group (HS/IR); (3) ischemia/reperfusion group (IR); and (4) heat stress group (HS). Animals in the last three groups were subdivided into three subgroups: 1 d, 4 d, 14 d respectively. The Morris water maze was used to test the ability of learning and memorizing, Nissl staining was used to count the average number of survived neurons in hippocampal CA1 region, and immunohistochemistry combined with image analysis system to detect the changes of Microtubule associated protein 2 (MAP-2) expression. The results showed that mice in IR group exhibited increased escape latency when compared with that of normal, HS and HS/IR groups (<0.01), and the mice in IR group adopted an inefficient search strategy, major in circling and restricted searching manners. Nissl staining results showed a significant reduction in the number of pyramidal neurons in hippocampal CA1 regions in HS/IR and IR groups, with a decrease in IR group (<0.01). Compared with normal group, the expression of MAP-2 in hippocampal CA1 region obviously decreased in IR group (<0.05). The present results indicate that heat stress pretreatment can improve the spatial learning and memorizing function through protection to hippocampal neurons.
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Bioaerosol emissions variations in large-scale landfill region and their health risk impacts

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1593-9

摘要：

● The airborne bacteria in landfills were 4–50 times higher than fungi.

关键词： Microbial aerosols     Landfill sites     Health risk assessment     CALPUFF    

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Carbon payments in the Guanzhong–Tianshui region to control land degradation

Zixiang ZHOU, Yufeng ZOU

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 246-253 doi: 10.15302/J-FASE-2017144

摘要： Carbon trading and carbon offset markets are potential policy options for mitigating greenhouse gas emissions and climate change. A price on carbon is expected to generate demand for carbon offsets. In a market-based framework, the carbon price should be high enough to compensate for opportunity costs. We studied a highly-modified agricultural system in the Guanzhong–Tianshui economic region of China that is typical of many temperate agricultural zones in western China. We quantified the economic returns from agriculture and from carbon plantings (both monoculture and ecological plantings) under five carbon-price scenarios. The mean carbon sequestration is 34 Mg·hm ·a , and the average annual payment increased to 1146 CNY·hm at a medium carbon price of 50 CNY·Mg CO . Thus, areas of high priority for conservation and restoration may be restored relatively cheaply in the presence of a carbon market. Overall, however, less carbon is sequestered by ecological plantings (i.e., mixed native trees and shrubs) compared to agriculture.

关键词： carbon-price     carbon sequestration     economic returns     Guanzhong–Tianshui economic region     net present value    

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基于Voronoi区的GIS中方向关系的描述与计算

李成名

《中国工程科学》 2013年 第15卷 第5期   页码 25-29

摘要：

方向关系在地理信息系统（GIS）中占据着十分重要的地位，由于它的模糊性和依赖空间实体形状的特性，使得它的形式化描述和判断比较困难。本文在三角形模型（CDR）方法的基础上，利用最小矩形（MBR）四边的Voronoi多边形及其边界，形式化描述了方向关系，进而将方向关系分为主方向关系和次方向关系，并分别给出了两者利用MBR四边Voronoi多边形及其边界判断的算法。

关键词： 方向关系     Voronoi区     CDR     MBR    

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SOIL NITROGEN CYCLING AND ENVIRONMENTAL IMPACTS IN THE SUBTROPICAL HILLY REGION OF CHINA: EVIDENCE FROM

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 407-424 doi: 10.15302/J-FASE-2022448

摘要：

● Soil nitrogen fluxes and influencing factors were reviewed in the subtropical hilly regions.

关键词： nitrogen cycling     soil nitrogen     nitrogen deposition     greenhouse gases emission     non-point source pollution     nitrogen use efficiency    

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过渡区提取方法综述

刘锁兰,杨静宇

《中国工程科学》 2007年 第9卷 第9期   页码 89-96

摘要：

图像分割是图像理论发展的瓶颈， 过渡区是指图像中介于目标和背景之间的 特殊区域，借助于过渡区的确定进行图像 分割。主要介绍了过渡区提取的两大类方法 ：基于梯度的方法和基于非梯度的方法， 并对提取效果以及存在的问题做了简要分析。

关键词： 过渡区     提取     图像分割     梯度法     非梯度法    

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Robust optimization of the billet for isothermal local loading transitional region of a Ti-alloy rib-web

Ke WEI, Xiaoguang FAN, Mei ZHAN, Miao MENG

《机械工程前沿（英文）》 2018年 第13卷 第3期   页码 376-384 doi: 10.1007/s11465-018-0500-3

摘要：

Billet optimization can greatly improve the forming quality of the transitional region in the isothermal local loading forming (ILLF) of large-scale Ti-alloy rib-web components. However, the final quality of the transitional region may be deteriorated by uncontrollable factors, such as the manufacturing tolerance of the preforming billet, fluctuation of the stroke length, and friction factor. Thus, a dual-response surface method (RSM)-based robust optimization of the billet was proposed to address the uncontrollable factors in transitional region of the ILLF. Given that the die underfilling and folding defect are two key factors that influence the forming quality of the transitional region, minimizing the mean and standard deviation of the die underfilling rate and avoiding folding defect were defined as the objective function and constraint condition in robust optimization. Then, the cross array design was constructed, a dual-RSM model was established for the mean and standard deviation of the die underfilling rate by considering the size parameters of the billet and uncontrollable factors. Subsequently, an optimum solution was derived to achieve the robust optimization of the billet. A case study on robust optimization was conducted. Good results were attained for improving the die filling and avoiding folding defect, suggesting that the robust optimization of the billet in the transitional region of the ILLF was efficient and reliable.

关键词： isothermal local loading forming     rib-web component     transitional region     robust optimization     dual response surface method    

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Tracking in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1533-8

摘要：

• Cryptosporidium in WWTPs in a cold region was investigated in different seasons.

关键词： WWTPs     Cryptosporidium     Occurrence     Species     Infectivity     Low temperature    

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Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

Jie LIU, Fan CHEN, Haiqing GENG, Xinxin QIU, Binbin CAI,

《环境科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 349-360 doi: 10.1007/s11783-010-0027-2

摘要： The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.

关键词： range of impact     quantitative analysis     highway construction     Longitudinal Range-Gorge Region    

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land use and land cover change on soil erosion and the spatio-temporal variation in Liupan Mountain Region

Bin QUAN, M. J. M. R?MKENS, Rui LI, Fang WANG, Jie CHEN

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 564-572 doi: 10.1007/s11783-011-0348-9

摘要： The Liupan Mountains are located in the southern Ningxia Hui Autonomous Region of China, that forms an important divide between landforms and bio-geographic regions. The populated part of the Liupan Mountain Region has suffered tremendous ecological damage over time due to population pressure, excessive demand and inappropriate use of agricultural land resources. To present the relationship between land use/cover change and spatio-temporal variation of soil erosion, data sets of land use between the late 1980s and 2000 were obtained from Landsat Thematic Mapper (TM) imagery, and spatial models were used to characterize landscape and soil erosion conditions. Also, soil erosion in response to land use and land cover change were quantified and analyzed using data from geographical information systems and remote sensing. Soil erosion by water was the dominant mode of soil loss, while soil erosion by wind was only present on a relatively small area. The degree of soil erosion was classified into five severity classes: slight, light, moderate, severe, and very severe. Soil erosion in the Liupan Mountain Region increased between the late 1980s and 2000, both in terms of acreage and severity. Moderate, severe, and very severe eroded areas accounted for 54.86% of the total land area. The lightly eroded area decreased, while the moderately eroded area increased by 368817 ha (22%) followed by severe erosion with 146552 ha (8.8%), and very severe erosion by 97067.6 ha (5.8%). Soil loss on sloping cropland increased with slope gradients. About 90% of the cropland was located on slopes less than 15°. Most of the increase in soil erosion on cropland was due to conversion of steep slopes to cropland and degradation of grassland and increased activities. Soil erosion was severe on grassland with a moderate or low grass cover and on dry land. Human activities, cultivation on steep slopes, and overgrazing of pastures were the main reasons for the increase in erosion severity.

关键词： land use/land cover change     soil erosion     geographical information system     remote sensing     Liupan Mountain Region    

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我国西北地区水资源开发利用对策的建议

赵文津

《中国工程科学》 2004年 第6卷 第8期   页码 21-27

摘要：

淡水资源是人类生存与经济社会发展的物质基础。我国西北地区的经济开发与发展，水资源问题特别突出。文章就西北地区开发中贯彻“人与自然和谐共存的方针”问题作了进一步讨论，提出在开发利用西北水资源过程中，必须从西北地区水资源总量不大，年蒸发量特别大，年降水量又很小的情况出发，积极节流开源，节约用水，防止水资源浪费，提高用水效益，减少水的污染，回收水资源，改善环境。建议积极走“藏水于地下”，扩大地下水与合理开发地下水之路。同时坚持不断地扩大可用的淡水资源。

关键词： 水资源     开发利用     中国西北地区    

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Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

《能源前沿（英文）》 2008年 第2卷 第4期   页码 514-518 doi: 10.1007/s11708-008-0076-4

摘要： A study of the chaotic behavior of liquefied natural gas (LNG) after stratification in the main stream region of a storage tank was conducted. Based on non-linear dynamics, a 2-dimensional Rayleigh-Benard convection model was developed to simulate the convection, Lorenz equations of LNG convection were deduced from conservation equations, and the Runge-Kutta method was used to solve the equations. The results showed that when = 1.33, 106 < < 1470, chaos was obtained, which meant that the velocity field and the temperature field were highly unsteady. In addition, the influence of temperature and scale factor on the solutions and the corresponding range of parameters were studied. The results revealed that the chaos in LNG convection resulted from the interaction of buoyancy and viscid forces. A small quantity of heat impacting the storage tank would lead to a strong and unstable convection of LNG in the main stream region.

关键词： Runge-Kutta     non-linear     corresponding     temperature     addition    

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“川气东送”工程资源基础与前景

马永生,蔡勋育,赵培荣,罗毅

《中国工程科学》 2010年 第12卷 第5期   页码 73-77

摘要：

2007年，国家“十一五”重大工程“川气东送”工程正式启动，该项目对改善沿线六省两市能源结构和生态环境具有重大意义。3年后，勘探开发情况表明，川气东送的资源基础——普光气田是一个高产优质的大型气田，同时元坝、通南巴气田规模不断扩大，南江、镇巴地区显示良好油气勘探潜力。“川气东送”的资源基础是可靠的，其资源规模正不断扩大，具有良好的资源前景。

关键词： 川气东送     天然气     资源    

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标题 作者 时间 类型 操作

Repeats in the transcribed regions: comprehensive characterization and comparison of

Manosh Kumar BISWAS, Christoph MAYER, Xiuxin DENG

期刊论文

The comparative study of dwelling houses in the southwest multi-ethnic region, taking Fugong county for

Fang WANG, Jiaping LIU

期刊论文

Protective roles of heat stress on the neurons in hippocampal CA1 region of mice

WANG Chunxu, WANG Hanxing

期刊论文

Bioaerosol emissions variations in large-scale landfill region and their health risk impacts

期刊论文

Carbon payments in the Guanzhong–Tianshui region to control land degradation

Zixiang ZHOU, Yufeng ZOU

期刊论文

基于Voronoi区的GIS中方向关系的描述与计算

李成名

期刊论文

SOIL NITROGEN CYCLING AND ENVIRONMENTAL IMPACTS IN THE SUBTROPICAL HILLY REGION OF CHINA: EVIDENCE FROM

期刊论文

过渡区提取方法综述

刘锁兰,杨静宇

期刊论文

Robust optimization of the billet for isothermal local loading transitional region of a Ti-alloy rib-web

Ke WEI, Xiaoguang FAN, Mei ZHAN, Miao MENG

期刊论文

Tracking in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

期刊论文

Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

Jie LIU, Fan CHEN, Haiqing GENG, Xinxin QIU, Binbin CAI,

期刊论文

land use and land cover change on soil erosion and the spatio-temporal variation in Liupan Mountain Region

Bin QUAN, M. J. M. R?MKENS, Rui LI, Fang WANG, Jie CHEN

期刊论文

我国西北地区水资源开发利用对策的建议

赵文津

期刊论文

Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

期刊论文

“川气东送”工程资源基础与前景

马永生,蔡勋育,赵培荣,罗毅

期刊论文