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Spatial impacts of climate factors on regional agricultural and forestry biomass resources in north-eastern province of China

Wenyan Wang, Wei Ouyang, Fanghua Hao, Yun Luan, Bo Hu

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0864-8

摘要： Dynamic analysis of biomass combined NPP modeling has been adopted. Temperature trends to warming and precipitation has periodic fluctuation. Regional distribution of agricultural and forestry biomass is mutual and divergent. Precipitation is significantly positive correlated with agricultural biomass. Temperature is negative on forestry biomass in Lesser Khingan & northern Changbai. Precipitation plays positive effect on biomass in southwestern Changbai Mountain. The dynamics of agricultural and forestry biomass are highly sensitive to climate change, particularly in high latitude regions. Heilongjiang Province was selected as research area in North-east China. We explored the trend of regional climate warming and distribution feature of biomass resources, and then analyzed on the spatial relationship between climate factors and biomass resources. Net primary productivity (NPP) is one of the key indicators of vegetation productivity, and was simulated as base data to calculate the distribution of agricultural and forestry biomass. The results show that temperatures rose by up to 0.37°C/10a from 1961 to 2013. Spatially, the variation of agricultural biomass per unit area changed from -1.93 to 5.85 t·km ·a during 2000–2013. More than 85% of farmland areas showed a positive relationship between agricultural biomass and precipitation. The results suggest that precipitation exerts an overwhelming climate influence on agricultural biomass. The mean density of forestry biomass varied from 10 to 30 t·km . Temperature had a significant negative effect on forestry biomass in Lesser Khingan and northern Changbai Mountain, because increased temperature leads to decreased Rubisco activity and increased respiration in these areas. Precipitation had a significant positive relationship with forestry biomass in south-western Changbai Mountain, because this area had a warmer climate and stress from insufficient precipitation may induce xylem cavitation. Understanding the effects of climate factors on regional biomass resources is of great significance in improving environmental management and promoting sustainable development of further biomass resource use.

关键词： Biomass resources     Net primary productivity (NPP)     Climate change     Heilongjiang Province     China     Climate     Energy systems/technology     Other sustainability (specify)     Statistical methods     GIS     Model flow     CFD    

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华北地区生态保护与恢复的水资源效应研究

孙思琦,陈永喆,王聪,胡庆芳,吕一河

《中国工程科学》 2022年 第24卷 第5期   页码 97-106 doi: 10.15302/J-SSCAE-2022.05.012

摘要：

近年来，华北地区实施了一系列生态保护与恢复工程，植被生态状况发生了显著变化；探究区域植被恢复对水循环过程及水资源供需平衡的影响，对于完善生态恢复策略、实现区域水资源可持续利用十分重要。本文采用皮尔逊相关系数和莫兰指数，结合多源水参量数据进行综合性分析，阐释了植被和不同水参量的时空变化情况，甄别了植被保育与恢复下的水资源变化响应，进而探讨了华北地区水资源与植被恢复的权衡关系。研究结果表明，华北地区的生态保护与恢复工程成效显著，植被净初级生产力的增速约为恢复工程区外的2.3 倍；植被的扩张与蒸散量表现出空间与时间上的强相关性；植被恢复引起的蒸散量提高是引起水储量赤字或显著降低的主要原因。为此建议，华北地区可完善生态恢复策略，在植被保育与恢复过程中考虑水资源的限制作用；以自然恢复方式为主，促进生态恢复的可持续性、水资源的可利用性。

关键词： 华北地区；生态恢复工程；蒸散发；水储量；植被净初级生产力；自然恢复    

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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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Modelling and analysis of FMS productivity variables by ISM, SEM and GTMA approach

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《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 218-232 doi: 10.1007/s11465-014-0309-7

摘要：

Productivity has often been cited as a key factor in a flexible manufacturing system (FMS) performance, and actions to increase it are said to improve profitability and the wage earning capacity of employees. Improving productivity is seen as a key issue for survival and success in the long term of a manufacturing system. The purpose of this paper is to make a model and analysis of the productivity variables of FMS. This study was performed by different approaches viz. interpretive structural modelling (ISM), structural equation modelling (SEM), graph theory and matrix approach (GTMA) and a cross-sectional survey within manufacturing firms in India. ISM has been used to develop a model of productivity variables, and then it has been analyzed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are powerful statistical techniques. CFA is carried by SEM. EFA is applied to extract the factors in FMS by the statistical package for social sciences (SPSS 20) software and confirming these factors by CFA through analysis of moment structures (AMOS 20) software. The twenty productivity variables are identified through literature and four factors extracted, which involves the productivity of FMS. The four factors are people, quality, machine and flexibility. SEM using AMOS 20 was used to perform the first order four-factor structures. GTMA is a multiple attribute decision making (MADM) methodology used to find intensity/quantification of productivity variables in an organization. The FMS productivity index has purposed to intensify the factors which affect FMS.

关键词： FMS     ISM     EFA     SEM     GTMA    

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LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE -2020349

摘要：

Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

 

关键词： crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

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Grassland management practices in Chinese steppes impact productivity, diversity and the relationship

Yingjun ZHANG, Wenjie LU, Hao ZHANG, Jiqiong ZHOU, Yue SHEN

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 57-63 doi: 10.15302/J-FASE-2017192

摘要： Grasslands are crucial parts of the terrestrial ecosystem, with an extremely high differentiation of productivity and diversity across spatial scales and land use patterns. The practices employed to manage grassland, such as grazing, haymaking, fertilization or reseeding, can improve the grassland condition. This study focuses on the changes in productivity and diversity and the relationship between them as affected by management practices. Productivity and diversity have unequivocally been altered in response to different management practices. When grazing intensity of a typical steppe increased from 1.5 to 9 sheep per hectare, both productivity and diversity declined. Higher grazing intensity (6 to 9 sheep per hectare) accelerated loss of diversity because of lower productivity. Productivity was significantly improved but diversity was lost by fertilizing. N fertilization also reduced the sensitivity of diversity to productivity. A similar response was found in mown grassland with increased productivity and diversity but their relationship was negatively affected. Mowing also slowed down the decline in diversity as productivity increased. Reseeding purple-flowered alfalfa led to an increased diversity, while yellow-flowered alfalfa increased productivity significantly. The negative productivity-diversity relationship was transformed to a positive one by reseeding alfalfa. These results enhance understanding of how productivity, diversity and their relationships change in response to altered grassland management practices, and support an integrated approach for improving both productivity and diversity.

关键词： diversity     fertilizing     grassland management practice     grazing     mowing     productivity     reseeding    

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Research and industrialization of near-net rolling technology used in shaft parts

Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG

《机械工程前沿（英文）》 2018年 第13卷 第1期   页码 17-24 doi: 10.1007/s11465-018-0480-3

摘要：

Shaft part rolling is an efficient and green near-net shaping technology offering many advantages, including high production efficiency, high material utilization rate, high product quality, and excellent production environment. In this paper, the features of shaft part rolling are introduced along with the working principles of two main shaft part rolling technologies, namely, cross wedge rolling (CWR) and skew rolling (SR). In relation to this technology, some R&D achievements gained by the University of Science and Technology Beijing are summarized. Finally, the latest developments in shaft part rolling are presented, including SR steel balls, precise forming of camshaft blank by CWR, SR phosphorous copper balls at room temperature, and CWR hollow axle sleeve. Although the shaft part rolling technology has been widely used in China, it only accounts for about 15% of applicable parts at present. Nevertheless, this technology has broad application prospects.

关键词： cross wedge rolling     skew rolling     near-net rolling     shaft part    

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Evaluation of power regeneration in primary suspension for a railway vehicle

Ruichen WANG, Zhiwei WANG

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 265-278 doi: 10.1007/s11465-019-0571-9

摘要： To improve the fuel economy of rail vehicles, this study presents the feasibility of using power regenerating dampers (PRDs) in the primary suspension systems of railway vehicles and evaluates the potential and recoverable power that can be obtained. PRDs are configured as hydraulic electromagnetic-based railway primary vertical dampers and evaluated in parallel and series modes (with and without a viscous damper). Hydraulic configuration converts the linear behavior of the track into a unidirectional rotation of the generator, and the electromagnetic configuration provides a controllable damping force to the primary suspension system. In several case studies, generic railway vehicle primary suspension systems that are configured to include a PRD in the two configuration modes are modeled using computer simulations. The simulations are performed on measured tracks with typical irregularities for a generic UK passenger route. The performance of the modified vehicle is evaluated with respect to key performance indicators, including regenerated power, ride comfort, and running safety. Results indicate that PRDs can simultaneously replace conventional primary vertical dampers, regenerate power, and exhibit desirable dynamic performance. A peak power efficiency of 79.87% is theoretically obtained in series mode on a top-quality German Intercity Express track (Track 270) at a vehicle speed of 160 mile/h (~257 km/h).

关键词： railway vehicle     primary damper     power regeneration     ride comfort     running safety    

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Dynein axonemal heavy chain 10 deficiency causes primary ciliary dyskinesia in humans and mice

《医学前沿（英文）》   页码 957-971 doi: 10.1007/s11684-023-0988-8

摘要： Primary ciliary dyskinesia (PCD) is a congenital, motile ciliopathy with pleiotropic symptoms. Although nearly 50 causative genes have been identified, they only account for approximately 70% of definitive PCD cases. Dynein axonemal heavy chain 10 (DNAH10) encodes a subunit of the inner arm dynein heavy chain in motile cilia and sperm flagella. Based on the common axoneme structure of motile cilia and sperm flagella, DNAH10 variants are likely to cause PCD. Using exome sequencing, we identified a novel DNAH10 homozygous variant (c.589C > T, p.R197W) in a patient with PCD from a consanguineous family. The patient manifested sinusitis, bronchiectasis, situs inversus, and asthenoteratozoospermia. Immunostaining analysis showed the absence of DNAH10 and DNALI1 in the respiratory cilia, and transmission electron microscopy revealed strikingly disordered axoneme 9+2 architecture and inner dynein arm defects in the respiratory cilia and sperm flagella. Subsequently, animal models of Dnah10-knockin mice harboring missense variants and Dnah10-knockout mice recapitulated the phenotypes of PCD, including chronic respiratory infection, male infertility, and hydrocephalus. To the best of our knowledge, this study is the first to report DNAH10 deficiency related to PCD in human and mouse models, which suggests that DNAH10 recessive mutation is causative of PCD.

关键词： DNAH10     mice     motile cilia     mutation     primary ciliary dyskinesia    

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Approach for natural gas to be a primary energy source in China

Weihe HUANG, Jindian CHEN, Chuan FU, Yan HUANG

《工程管理前沿（英文）》 2019年 第6卷 第4期   页码 467-476 doi: 10.1007/s42524-019-0068-6

摘要： This work reveals the positioning of natural gas in the evolution of world energy and the general law of its development. In the long-term adjustment of energy structure, natural gas has gradually become the primary energy source because of five factors: policy, resources, technology, facilities, and market. To expedite the revolution of energy production and consumption, China must urgently expand the use of natural gas toward a more positive role in complementing coal and renewable energy and prioritize its usage in three areas, namely, urban gas, power generation, and industrial fuel. Natural gas is expected to account for approximately 15% of China’s total energy consumption in the future. For natural gas to be the primary energy, the exploitation of gas resources must be expanded, resource access must be improved, a flexible trade system must be set up, infrastructure investment must be increased, and the security system must be enhanced.

关键词： natural gas     energy revolution     primary energy     utilization areas     approaching means    

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Strain and process engineering toward continuous industrial fermentation

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1336-1353 doi: 10.1007/s11705-022-2284-6

摘要： Most current biotechnology industries are based on batch or fed-batch fermentation processes, which often show low productivity and high production costs compared to chemical processes. To increase the economic competitiveness of biological processes, continuous fermentation technologies are being developed that offer significant advantages in comparison with batch/fed-batch fermentation processes, including: (1) removal of potential substrates and product inhibition, (2) prolonging the microbial exponential growth phase and enhancing productivity, and (3) avoiding repeated fermentation preparation and lowering operation and installation costs. However, several key challenges should be addressed for the industrial application of continuous fermentation processes, including (1) contamination of the fermentation system, (2) degeneration of strains, and (3) relatively low product titer. In this study, we reviewed and discussed metabolic engineering and synthetic biology strategies to address these issues.

关键词： continuous fermentation     productivity     contamination     strain degeneration     metabolic engineering    

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Effect of traditional Chinese medicine combined with Western therapy on primary hepatic carcinoma: a

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《医学前沿（英文）》 2017年 第11卷 第2期   页码 191-202 doi: 10.1007/s11684-017-0512-0

摘要：

Primary hepatic carcinoma (PHC) is a common malignant tumor in China. Cancer is comprehensively treated with various therapeutic regimes, including traditional Chinese medicine (TCM). TCM has been widely used to improve the quality of life, delay the time of cancer progression, and prolong the median survival time. This systematic review with meta-analysis aimed to assess the effect of TCM combined with Western therapy on primary hepatic carcinoma. A comprehensive literature search was conducted in six databases, including CNKI, VIP, Wan-Fang Database, CBM, PubMed, and Cochrane library. A total of 44 randomized controlled trials (RCTs) involving 3429 participants suffering from PHC were selected. Meta-analysis results indicated that the overall effect of TCM and Western integrative treatment on PHC was higher than that of Western intervention alone, which can postpone tumor recurrence and metastasis and prolong the overall survival time of patients with PHC. Although the obtained evidence remained weak because of the poor methodological quality of the included studies, this review provided relevant data supporting the efficacy and safety of TCM combined with Western therapies. In future research, individual RCT studies should incorporate accepted standards for trial design and reporting, proper outcome indicators according to international standards, blinding in allocation concealment, and valid follow-up periods.

关键词： traditional Chinese medicine     primary hepatic carcinoma     meta-analysis    

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LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE-2020349

摘要： Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

关键词： crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

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Tuning the primary selective nanochannels of MOF thin-film nanocomposite nanofiltration membranes for

《环境科学与工程前沿（英文）》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1474-7

摘要：

• PA layer properties tune the primary nanochannels in MIL-101(Cr) TFN NF membranes.

关键词： Porous metal organic framework     Thin-film nanocomposite membrane     Primary selective nanochannels     Nanofiltration     Endocrine disrupting compounds    

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Primary hypertrophic osteoarthropathy: an update

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《医学前沿（英文）》 2013年 第7卷 第1期   页码 60-64 doi: 10.1007/s11684-013-0246-6

摘要：

Digital clubbing, which has been recognized as a sign of systemic disease, is one of the most ancient diseases. However, the pathogenesis of clubbing and hypertrophic osteoarthropathy has hitherto been poorly understood. The study of a clinically indistinguishable idiopathic form (primary hypertrophic osteoarthropathy, PHO) provides an opportunity to understand the pathogenesis of hypertrophic osteoarthropathy. Current advances in the study of PHO are discussed. The impaired metabolism of prostaglandin E2 (PGE2) plays a central role in its pathogenesis.

关键词： digital clubbing     primary hypertrophic osteoarthropathy     prostaglandin E2 (PGE2)    

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标题 作者 时间 类型 操作

Spatial impacts of climate factors on regional agricultural and forestry biomass resources in north-eastern province of China

Wenyan Wang, Wei Ouyang, Fanghua Hao, Yun Luan, Bo Hu

期刊论文

华北地区生态保护与恢复的水资源效应研究

孙思琦,陈永喆,王聪,胡庆芳,吕一河

期刊论文

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

Modelling and analysis of FMS productivity variables by ISM, SEM and GTMA approach

null

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

期刊论文

Grassland management practices in Chinese steppes impact productivity, diversity and the relationship

Yingjun ZHANG, Wenjie LU, Hao ZHANG, Jiqiong ZHOU, Yue SHEN

期刊论文

Research and industrialization of near-net rolling technology used in shaft parts

Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG

期刊论文

Evaluation of power regeneration in primary suspension for a railway vehicle

Ruichen WANG, Zhiwei WANG

期刊论文

Dynein axonemal heavy chain 10 deficiency causes primary ciliary dyskinesia in humans and mice

期刊论文

Approach for natural gas to be a primary energy source in China

Weihe HUANG, Jindian CHEN, Chuan FU, Yan HUANG

期刊论文

Strain and process engineering toward continuous industrial fermentation

期刊论文

Effect of traditional Chinese medicine combined with Western therapy on primary hepatic carcinoma: a

null

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

期刊论文

Tuning the primary selective nanochannels of MOF thin-film nanocomposite nanofiltration membranes for

期刊论文

Primary hypertrophic osteoarthropathy: an update

null

期刊论文