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The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要： The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词： ecological footprint     equivalence factor     net primary production     biological capacity     land types    

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Nucleate boiling in two types of vertical narrow channels

Lei GUO, Shusheng ZHANG, Lin CHENG

《能源前沿（英文）》 2011年 第5卷 第3期   页码 250-256 doi: 10.1007/s11708-010-0128-4

摘要： To explore the mechanism of boiling bubble dynamics in narrow channels, we investigate 2-mm wide I- and Z-shaped channels. The influence of wall contact angle on bubble generation and growth is studied using numerical simulation. The relationships between different channel shapes and the pressure drop are also examined, taking into account the effects of gravity, surface tension, and wall adhesion. The wall contact angle imposes considerable influence over the morphology of bubbles. The smaller the wall contact angle, the rounder the bubbles, and the less time the bubbles take to depart from the wall. Otherwise, the bubbles experience more difficulty in departure. Variations in the contact angle also affect the heat transfer coefficient. The greater the wall contact angle, the larger the bubble-covered area. Therefore, wall thermal resistance increases, bubble nucleation is suppressed, and the heat transfer coefficient is lowered. The role of surface tension in boiling heat transfer is considerably more important than that of gravity in narrow channels. The generation of bubbles dramatically disturbs the boundary layer, and the bubble bottom micro-layer can enhance heat transfer. The heat transfer coefficient of Z-shaped channels is larger than that of the I-shaped type, and the pressure drop of the former is clearly higher.

关键词： nucleate boiling     narrow channel     numerical simulation     bubble dynamics    

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核电先进堆型与我国核电发展

胡亚蕾

《中国工程科学》 2005年 第7卷 第11期   页码 98-102

摘要：

介绍了核电堆型发展的四个阶段和第一、二代核电堆型的发展历史；论述了第三代先进堆型的发展、设计特点和第四代先进堆的开发目标。

关键词： 核电     先进堆型     中国核电    

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Effects of different types of biochar on the properties and reactivity of nano zero-valent iron in soil

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-021-1388-4

摘要：

• Biochar enhanced the mobility and stability of zero-valent iron nanoparticles.

关键词： Nano zero-valent iron     Biochar     BDE209     Transport     Soil    

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Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 411-434 doi: 10.1007/s11709-019-0602-y

摘要： It is remarkable, the recent advances concerning the development of numerical modeling frameworks to simulate the infill panels’ seismic behavior. However, there is a lack of experimental data of their mechanical properties, which are of full importance to calibrate the numerical models. The primary objective of this paper is to present an extensive experimental campaign of mechanical characterization tests of infill masonry walls made with three different types of masonry units: lightweight vertical hollow concrete blocks and hollow clay bricks. Four different types of experimental tests were carried out, namely: compression strength tests, diagonal tensile strength tests, and flexural strength tests parallel and perpendicular to the horizontal bed joints. A total amount of 80 tests were carried out and are reported in the present paper. The second objective of this study was to compare the mechanical properties of as-built and existing infill walls. The results presented and discussed herein, will be in terms of strain-stress curves and damages observed within the tests. It was observed a fragile behavior in the panels made with hollow clay horizontal bricks, without propagation of cracks. The plaster increased the flexural strength by 57%.

关键词： masonry infill walls     experimental characterization     compression strength     shear diagonal strength     flexural strength    

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Exploring differentiated improvement strategies of cultivated land quality in China

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023523

摘要：

● Cultivated land quality can be considered in four dimensions: suitability, contiguity, resistance, and ecological stress.

关键词： China     cultivated land quality     differentiated improvement     food security    

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Effect of land use and land cover change on soil erosion and the spatio-temporal variation in Liupan

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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Vehicle-bridge coupled vibrations in different types of cable stayed bridges

Lingbo WANG,Peiwen JIANG,Zhentao HUI,Yinping MA,Kai LIU,Xin KANG

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 81-92 doi: 10.1007/s11709-015-0306-x

摘要： Numerical analyses of the coupled vibrations of vehicle-bridge system and the effects of different types of cable stayed bridges on the coupled vibration responses have been presented in this paper using ANSYS. The bridge model and vehicle model were independently built which have no internal relationship in the ANSYS. The vehicle-bridge coupled vibration relationship was obtained by using the APDL program which subsequently imposed on the vehicle and bridge models during the numerical analysis. The proposed model was validated through a field measurements and literature data. The judging method, possibility, and criterion of the vehicle-bridge resonance (coupled vibrations) of cable stayed bridges (both the floating system and half floating system) under traffic flows were presented. The results indicated that the interval time between vehicles is the main influence factor on the resonance excitation frequency under the condition of equally spaced traffic flows. Compared to other types of cable stayed bridges, the floating bridge system has relatively high possibility to cause vehicle-bridge resonance.

关键词： vehicle-bridge coupled vibration     cable stayed bridge     resonances of vehicle-bridge system    

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Evaluating heavy metal contamination of riverine sediment cores in different land-use areas

Wenzhong Tang, Liu Sun, Limin Shu, Chuang Wang

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1283-4

摘要： Abstract • Metal pollution was studied in riverine sediments from different land-use areas. • Cd was the most serious heavy metal contaminant in riverine sediment cores. • Riverine sediment cores from industrial area were most polluted by heavy metals. • B1 fraction determined metal pollution, risk and toxicity in riverine sediments. Anthropogenic activities are regarded as the main sources of heavy metal pollution, yet few studies have investigated the effects of land-use setting on heavy metal accumulation in riverine sediments. Based on both total contents and geochemical fractions, heavy metal pollution, risk and toxicity were determined in riverine sediment cores from different land-use areas (mountain area- MA, farm area- FA, city area- CA, and industrial area- IA) of the Yang River Basin in North China. The results showed that FA had higher contents of riverine sedimentary Cu; CA had higher contents of Cd; IA had higher contents of both Cd and Zn. Most riverine sediments from FA and IA were contaminated with the investigated metals, although these concentrations were evaluated to have low potential ecological risk and no toxicity to benthic organisms. However, a high proportion of Cd in the B1 fraction of riverine sediments in IA indicating high risk should receive more attention. The B1 fraction largely determined the contamination, risk and toxicity levels associated with heavy metals in the riverine sediments of the Yang River Basin.

关键词： Heavy metals     Riverine sediments     Pollution     Land-use    

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Field scale measurement of greenhouse gas emissions from land applied swine manure

Devin L. Maurer, Jacek A. Koziel, Kelsey Bruning

《环境科学与工程前沿（英文）》 2017年 第11卷 第3期 doi: 10.1007/s11783-017-0915-9

摘要： Greenhouse gas emissions (GHGs) from swine production systems are relatively well researched with the exception of emissions from land application of manure. GHGs inventories are needed for process-based modeling and science-based regulations. Thus, the objective of this observational study was to measure GHG fluxes from land application of swine manure on a typical corn field. Assessment of GHG emissions from deep injected land-applied swine manure, fall and reapplication in the spring, on a typical US Midwestern corn-on-corn farm was completed. Static chambers were used for flux measurement along with gas analysis on a GC-FID-ECD. Measured gas concentrations were used to estimate GHGs flux using four different models: linear regression, nonlinear regression, first order linear regression and the revised Hutchinson and Mosier (HMR) model, respectively for comparisons. Cumulative flux estimates after manure application of 5.85 × 10 g·ha (1 ha= 0.01 km ) of CO , 6.60 × 10 g·ha of CH , and 3.48 × 10 g·ha N O for the fall trial and 3.11 × 10 g·ha of CO , 2.95 × 10 g·ha of CH , and 1.47 × 10 g·ha N O after the spring reapplication trial were observed. The N O net cumulative flux represents 0.595% of nitrogen applied in swine manure for the fall trial.

关键词： Climate change     Emissions     Greenhouse gases     Land application     Swine manure    

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A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 332-341 doi: 10.1007/s11465-019-0540-3

摘要： This study focuses on establishing non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems when the dual boundary element method is applied. The asymptotic behavior of the physical variables in the area near the crack front is fully considered in the construction of the shape function. In the developed quadrilateral and triangular crack front elements, the asymptotic term, which captures the asymptotic behavior of the physical variable, is multiplied directly by the conventional Lagrange shape function to form a new crack front shape function. Several benchmark numerical examples that consider penny-shaped cracks and straight-edge crack problems are presented to illustrate the validity and efficiency of the developed crack front elements.

关键词： Taylor expansion     crack front elements     stress intensity factors     dual boundary element method    

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Optimization of Land-use Based on the Theory of Cellular Automata and Value of Ecosystem Services

Lian-fu Jiang,Guo-xian Xu,Hao Jiang

《工程管理前沿（英文）》 2014年 第1卷 第4期   页码 395-401 doi: 10.15302/J-FEM-2014058

摘要： The main objective of the study was to confirm the location and configuration of “Habitat Conservation Area” in Dongguan City. The land utilization condition in the target city was simulated using Arc GIS and Geo SOS software basing on multi-criteria decision model of Cellular Automata (CA). Both the simulation result and accuracy satisfied well the basic requirements. In addition to multi-criteria decision model, space optimization technique was used as well in simulation experiments.

关键词： Ecosystem service function     optimization of land use     Cellular Automata (CA)    

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Simulation of soil carbon changes due to land use change in urban areas in China

Cui HAO, Jo SMITH, Jiahua ZHANG, Weiqing MENG, Hongyuan LI

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 255-266 doi: 10.1007/s11783-013-0485-4

摘要： Land use change can have a strong impact on soil carbon dynamics and carbon stocks in urban areas. Due to rapid urbanization, large areas of land have been paved, and other areas have undergone rapid land use change. Evaluation of the impact of urbanization on carbon dynamics and carbon stock (30 cm) has become an issue of urgent concern. The soil carbon dynamics, due to rapid land use change in Tianjin Binhai New Area of China, have been simulated in this paper using the RothC model. Because this area is saline, a modified version of RothC that includes a salt rate modifier provided more accurate simulations than the original model. The conversion to urban green land was not accurately simulated by either of the models because of the undefined changes in soil and plant conditions. According to the model, changes of arable to grassland resulted in a decline in soil carbon stocks, and changes of grassland to forest and grassland to arable resulted in increased soil carbon stocks in this area. Across the whole area simulated, the total carbon stocks in 2010 had decreased due to land use change by 6.5% from the 1979 value. By 2050, a further decrease of 21.9% is expected according to the 2050 plan for land use and the continuing losses from the soils due to previous land use changes.

关键词： land use change     soil carbon     RothC     urban area    

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海陆关联工程科技发展战略

“中国海洋工程与科技发展战略研究”海陆关联课题组

《中国工程科学》 2016年 第18卷 第2期   页码 49-54 doi: 10.15302/J-SSCAE-2016.02.005

摘要：

海陆关联工程是指在建设和运行中同时涉及陆域和海域并发挥显著作用或产生重大影响的工程项目，主要包括港口、跨海桥梁、海底隧道、填海工程等。近年来，我国海陆关联工程的建设快速发展，工程技术的总体水平得到了提高，在沿海经济发展中发挥了显著的作用，但也存在发展不平衡、协调性较差、环境和安全管理相对薄弱等问题。未来我国应逐步推进从沿海到深海大洋、从示范试点到全面铺开、从单一工程到复合工程的海陆关联工程体系的建设，重点在沿海产业涉海工程布局、海陆物流联运工程、海岛开发与保护工程、沿海重大防灾减灾工程等领域强化海陆关联工程的建设。

关键词： 海陆关联工程     海岸带     海洋工程     陆海统筹    

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Effects of land use change on hydrological cycle from forest to upland field in a catchment, Japan

Chuan ZHANG, Keiji TAKASE, Hiroki OUE, Nobuhiro EBISU, Haofang YAN

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 456-465 doi: 10.1007/s11709-013-0218-6

摘要： Understanding the effects of land use change on the hydrological cycle is very important for development of sustainable water resource in an upland field catchment. In this study, soil and hydrological properties in an upland field catchment, which was reclaimed partially from a forest catchment, were compared with another forest catchment. The soil properties of surface and subsurface layers were investigated in the two catchments. The soil was compacted and water-holding capacity of soil in the upland field catchment became smaller after the reclamation from forest to upland field, which decreased infiltration rate and water storage in the soil layers. We found that peak discharge and direct runoff in the upland field catchment increased compared with the forest catchment. Annual evapotranspiration from the upland field catchment tended to be lower due to the change in vegetation type and soil properties. Furthermore, a semi-distributed hydrological model was applied in the upland field catchment to understand the integrated effects of reclamation on the hydrological cycle. The model parameters, which were determined using a nonlinear optimization technique—the Shuffled Complex Evolution method (SCE), were compared between the two catchments. The Nash and Sutcliffe coefficient was used to evaluate the model performance. The simulated results indicated that evapotranspiration was decreased and change in discharge was more obvious in the surface layer. We considered that declined infiltration and water storage and increased peak discharge and direct runoff have a negative impact on water resources in the upland field catchment. This study will provide information for forest managers in planning and making decisions for land and water resource management.

关键词： land-use change     hydrological processes     upland field catchment     forest catchment     semi-distributed hydrological model    

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标题 作者 时间 类型 操作

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

期刊论文

Nucleate boiling in two types of vertical narrow channels

Lei GUO, Shusheng ZHANG, Lin CHENG

期刊论文

核电先进堆型与我国核电发展

胡亚蕾

期刊论文

Effects of different types of biochar on the properties and reactivity of nano zero-valent iron in soil

期刊论文

Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

期刊论文

Exploring differentiated improvement strategies of cultivated land quality in China

期刊论文

Effect of land use and land cover change on soil erosion and the spatio-temporal variation in Liupan

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

期刊论文

Vehicle-bridge coupled vibrations in different types of cable stayed bridges

Lingbo WANG,Peiwen JIANG,Zhentao HUI,Yinping MA,Kai LIU,Xin KANG

期刊论文

Evaluating heavy metal contamination of riverine sediment cores in different land-use areas

Wenzhong Tang, Liu Sun, Limin Shu, Chuang Wang

期刊论文

Field scale measurement of greenhouse gas emissions from land applied swine manure

Devin L. Maurer, Jacek A. Koziel, Kelsey Bruning

期刊论文

A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

期刊论文

Optimization of Land-use Based on the Theory of Cellular Automata and Value of Ecosystem Services

Lian-fu Jiang,Guo-xian Xu,Hao Jiang

期刊论文

Simulation of soil carbon changes due to land use change in urban areas in China

Cui HAO, Jo SMITH, Jiahua ZHANG, Weiqing MENG, Hongyuan LI

期刊论文

海陆关联工程科技发展战略

“中国海洋工程与科技发展战略研究”海陆关联课题组

期刊论文

Effects of land use change on hydrological cycle from forest to upland field in a catchment, Japan

Chuan ZHANG, Keiji TAKASE, Hiroki OUE, Nobuhiro EBISU, Haofang YAN

期刊论文