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The Impact of Human Resource Management on Regional Economic Development
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作者 Ruicheng Zhou 《Proceedings of Business and Economic Studies》 2024年第3期35-41,共7页
A company that does a good job in human resource management will promote the process of regional economic development,and related enterprises will develop rapidly as a result.In future work,enterprises should carefull... A company that does a good job in human resource management will promote the process of regional economic development,and related enterprises will develop rapidly as a result.In future work,enterprises should carefully study the relationship between the two,and innovate their human resource management and development methods while fully considering the needs of talent development and regional economic development,in order to fundamentally optimize the regional economic development status. 展开更多
关键词 Human resource management impact on regional economic development
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Impact of Plastic Waste on the Human Health in Low-Income Countries: A Systematic Review
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作者 Ramde Wendkoaghenda Sophie Gbandama Koffi Kouame Pacome +5 位作者 Gansore Aminata Camara Kelety Tolno Barthélemy Assogba Ange Wenceslas Vinciale Niare Boubacar Patrice Ngangue 《Journal of Environmental Protection》 2024年第5期572-595,共24页
Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pol... Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pollution poses significant threats to terrestrial and aquatic habitats and the wildlife that call them home, whether through ingestion, entanglement or exposure to the chemicals contained in the material. Unfortunately, there is a lack of documentation on the impact of plastic waste on human health in low- and middle-income countries (LMICs). Methods: We searched five electronic databases (PubMed, Embase, Global Health, CINAHL and Web of Science) and gray literature, following the preferred reporting elements for systematic reviews and meta-analyses (PRISMA), for the impact of plastic waste on human health in developing countries. We included quantitative and qualitative studies written in English and French. We assessed the quality of the included articles using the Mixed Methods Appraisal tool (MMAT). Results: A total of 3779 articles were initially identified by searching electronic databases. After eliminating duplicates, 3167 articles were reviewed based on title and abstract, and 26 were selected for full-text review. Only three articles were retained. The three articles dealt with practices likely to lead to oral exposure to plastic chemicals in human health, as well as the level of awareness of participants concerning the possible impact of plastic on human health, namely, the use of plastic baby bottles, the use of microwaves to cook food and reheat precooked food, the use of plastic bottles to store water in the refrigerator, water purifier containers with plastic bodies and plastic lunch boxes, the reuse of plastic bags and the inadequacy of treatment facilities. Conclusion: Plastic waste poses different risks to human health at every stage of its life cycle. Hence, strategies must be adopted to raise public awareness of the dangers of plastic waste to their health. Trial registration: The review protocol is registered in the PROSPERO international prospective register of systematic reviews (ID = CRD42023409087). 展开更多
关键词 Human Population Plastic Waste Health impact low-Income-Countries (Humans Iatrogenic Disease PLASTICS POLICY RECYCLING Waste Management)
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An overview of efficient development practices at low permeability sandstone reservoirs in China 被引量:1
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作者 Bingyu Ji Jichao Fang 《Energy Geoscience》 2023年第3期149-157,共9页
Low permeability sandstone reservoirs in China typically have more complicated geological conditions, pore structures, and flow characteristics as compared to medium-to-high-permeability sandstone reservoirs. Traditio... Low permeability sandstone reservoirs in China typically have more complicated geological conditions, pore structures, and flow characteristics as compared to medium-to-high-permeability sandstone reservoirs. Traditional geological and seepage theories, and engineering methods are not applicable to the development of these low permeability reservoirs, and wells drilled into them often produce oil and gas at very low rates. Recent breakthroughs in reservoir exploitation technology have greatly improved the productivity of low permeability reservoirs, making them the primary target for oil exploration and extraction in China. The development theories and practices applied to low permeability reservoirs in China are reviewed in this study— based on relevant geological and engineering practices, including drilling, fracturing, recovery, and surface engineering. A unique series of technological advances that aid the development of low permeability reservoirs in China are summarized here. This study may serve as a meaningful guide in achieving scale efficiency for the development of low permeability reservoirs. 展开更多
关键词 Well pattern FRACTURING development model Reservoir description low permeability reservoir
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Construction Approaches of Urban Spongy Park Based on Low Impact Development 被引量:4
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作者 CHEN Xiaogang YANG Qinliang YANG Kun 《Journal of Landscape Research》 2016年第3期27-30,共4页
Rapid urbanization has brought various water-concerning problems to cities, such as water source scarcity, water pollution, fl ood disaster, and habitat loss of aquatic life, Low Impact Development(LID) is a signifi c... Rapid urbanization has brought various water-concerning problems to cities, such as water source scarcity, water pollution, fl ood disaster, and habitat loss of aquatic life, Low Impact Development(LID) is a signifi cant approach of solving these problems. Through sorting out causes and connotations of LID and urban spongy park, this proposed that fl exible design is the core content of spongy park construction, and on this basis analyzed objectives, contents and approaches of urban spongy park construction, put forward strategies suitable for the construction of urban spongy parks in China, in order to instruct future construction of domestic urban spongy parks and promote the development of ecological civilization. 展开更多
关键词 low impact development Spongy park Rainwater management
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Multi-Objective Optimization of Low Impact Development Designs in an Urbanizing Watershed 被引量:1
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作者 Guoshun Zhang James M. Hamlett +1 位作者 Patrick Reed Yong Tang 《Open Journal of Optimization》 2013年第4期95-108,共14页
Multi-objective optimization linked with an urban stormwater model is used in this study to identify cost-effective low impact development (LID) implementation designs for small urbanizing watersheds. The epsilon-Non-... Multi-objective optimization linked with an urban stormwater model is used in this study to identify cost-effective low impact development (LID) implementation designs for small urbanizing watersheds. The epsilon-Non-Dominated Sorting Genetic Algorithm II (ε-NSGAII) has been coupled with the US Environmental Protection Agency’s Stormwater Management Model (SWMM) to balance the costs and the hydrologic benefits of candidate LID solutions. Our objective in this study is to identify the near-optimal tradeoff between the total LID costs and the total watershed runoff volume constrained by pre-development peak flow rates. This study contributes a detailed analysis of the costs and benefits associated with the use of green roofs, porous pavement, and bioretention basins within a small urbanizing watershed inState College,Pennsylvania. Beyond multi-objective analysis, this paper also contributes improved SWMM representations of LID alternatives and demonstrates their usefulness for screening alternative site layouts for LID technologies. 展开更多
关键词 MULTI-OBJECTIVE Optimization ε-NSGAII low impact development SWMM STORMWATER
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Research on the Development of Green Hotels in the Context of Low Carbon Tourism
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作者 Ze Hui Fan Fang Huang Jiang Tao Li 《Proceedings of Business and Economic Studies》 2023年第5期59-65,共7页
With the continuous implementation of national measures related to carbon neutrality strategy,the concept of a low-carbon economy has been deeply rooted in people’s hearts.Low-carbon tourism has gradually become an i... With the continuous implementation of national measures related to carbon neutrality strategy,the concept of a low-carbon economy has been deeply rooted in people’s hearts.Low-carbon tourism has gradually become an inevitable trend,and the tourism industry is also undergoing orderly transformation and upgrading.To promote the sustainable development of the tourism industry,the tourism and hotel industry should also shift towards a low-carbon and green model.Hotel activities can easily bring related environmental issues,such as energy consumption,garbage generation,ecological pollution,etc.Therefore,building a green hotel will bring huge social and economic benefits to the low-carbon tourism industry.This article will address the above issues and take a low-carbon economy as the starting point,proposing sustainable development strategies and suggestions for green hotels from both the internal and external environment of the hotel,creating a low-carbon management atmosphere,and promoting the low-carbon operation of the green hotel industry. 展开更多
关键词 low carbon tourism Green hotels Sustainable development
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Low-Impact Development(LID) of the Water Ecological Environment in Rural Areas: A Case Study of the Wei River Wetland in Fengxi New City of Xixian New Area
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作者 LIU Linggui SUN Xueyang 《Journal of Landscape Research》 2019年第4期35-38,共4页
The problem of rural water ecological environment is becoming growingly prominent, and its ecological management is of great significance. From sponge cities to sponge villages, it is an effective way to use the low-i... The problem of rural water ecological environment is becoming growingly prominent, and its ecological management is of great significance. From sponge cities to sponge villages, it is an effective way to use the low-impact development (LID) technology to solve rural water ecological environment problems. Through the investigation and analysis of the hydrology, soil, runoff, vegetation and other factors in the Wei River wetland of Fengxi New City of Xixian New Area, this study attempts to construct a LID route suitable for managing the rural water ecological environment in the northwest, so as to provide a reference for the construction of green infrastructure and sponge cities of rural areas in the northwest. 展开更多
关键词 Rural landscape Water ecological environment low impact development SPONGE city
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Impact of Low-Impact Development Technologies from an Ecological Perspective in Different Residential Zones of the City of Atlanta, Georgia 被引量:2
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作者 Zackery B. Morris Stephen M. Malone +2 位作者 Abigail R. Cohen Marc J. Weissburg Bert Bras 《Engineering》 2018年第2期30-35,共6页
低影响开发(LID)技术在减少水的使用和雨水径流方面有很大的应用潜力,因此被认为在对传统的水利基础设施的改善方面起到可持续性的作用。这些技术包括生物凝集区、雨水收集和干湿法,所有这些都可以在居住区使用。在亚特兰大市,居民用水... 低影响开发(LID)技术在减少水的使用和雨水径流方面有很大的应用潜力,因此被认为在对传统的水利基础设施的改善方面起到可持续性的作用。这些技术包括生物凝集区、雨水收集和干湿法,所有这些都可以在居住区使用。在亚特兰大市,居民用水占总用水量的53%,因此,居住区对LID技术的实施具有重要的潜在影响力。本研究通过对自然生态系统的类比,从生态学角度分析了亚特兰大城市不同居住区内LID策略的使用情况。分析表明这些技术,特别是随着灰水系统的加入,在这些生态指标的基础上,改进了传统的住宅水网。较高的指标表明,改进后的指标与健康的自然生态系统的平衡程度更高。 展开更多
关键词 可持续改进 水基础设施 施工方案 施工管理
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The Impacts of Lower Population Growth on the Quality of Life and Economic Development:China's Experience
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作者 Jiang Zhenghua & Zhang Lingguang 《China Population Today》 1994年第1期4-7,1,共5页
China is the most populous country in the world.The total Population on the mainland of China has in-creased from 540 million in 1949 to 1.18 billion by the end of 1993.China adopted a population policy by namc of&quo... China is the most populous country in the world.The total Population on the mainland of China has in-creased from 540 million in 1949 to 1.18 billion by the end of 1993.China adopted a population policy by namc of"controlling population growth and im-proving the quality of the human resources',which has been deeply rooted in the hearts of the Chinese pcoplc.The overw helming majority of the Chinese people have recognized the necessity for implementing the family planning programme not only for the sustained devel-opment of the country,but also for the benefits of their own familie cs. 展开更多
关键词 lowER POPULATION ECONOMIC EXPERIENCE Growth impactS LIFE China development Quality
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Critical Success Factors for Citizen Development
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作者 Natalie Callinan Martin Perry 《Open Journal of Applied Sciences》 2024年第4期1121-1149,共29页
The purpose of the research was to assess the impact of Citizen Development activities on digital transformation. The research identified eight categories that contribute to the success of Low-code No-code (LCNC) proj... The purpose of the research was to assess the impact of Citizen Development activities on digital transformation. The research identified eight categories that contribute to the success of Low-code No-code (LCNC) projects: 1) Strategy;2) Infrastructure;3) Technology;4) Processes & Procedures;5) Governance;6) Culture;7) People;8) Goals & Metrics and selected six critical success factors from these categories: 1) Operational Efficiency;2) Time Savings;3) Timeframe to Realize Value;4) Employee Engagement;5) Participation;6) Number of Sponsored Ideas. End users of the digital transformation efforts through Citizen Development were asked to assess the six critical success measures in terms of performance and importance criteria. The research results identified that focus should be applied to improving “Timeframe to Realize Value”, on “Operational Efficiency”, and on “Time Savings” to deliver success. 展开更多
关键词 Citizen development low-Code No-Code Application development Digital Transformation Timeframe to Realize Value Employee Engagement
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Low impact development technologies for mitigating climate change:Summary and prospects
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作者 Zhonghao Zhang Caterina Valeo 《National Science Open》 2024年第1期75-99,共25页
Many cities are adopting low impact development(LID)technologies(a type of nature-based solution)to sustainably manage urban stormwater in future climates.LIDs,such as bioretention cells,green roofs,and permeable pave... Many cities are adopting low impact development(LID)technologies(a type of nature-based solution)to sustainably manage urban stormwater in future climates.LIDs,such as bioretention cells,green roofs,and permeable pavements,are developed and applied at small-scales in urban and peri-urban settings.There is an interest in the large-scale implementation of these technologies,and therefore assessing their performance in future climates,or conversely,their potential for mitigating the impacts of climate change,can be valuable evidence in support of stormwater management planning.This paper provides a literature review of the studies conducted that examine LID function in future climates.The review found that most studies focus on LID performance at over 5 km2scales,which is quite a bit larger than traditional LID sizes.Most paper used statistical downscaling methods to simulate precipitation at the scale of the modelled LID.The computer model used to model LIDs was predominantly SWMM or some hybrid version of SWMM.The literature contains examples of both vegetated and unvegetated LIDs being assessed and numerous studies show mitigation of peak flows and total volumes to high levels in even the most extreme climates(characterized by increasing rainfall intensity,higher temperatures,and greater number of dry days in the inter-event period).However,all the studies recognized the uncertainty in the projections with greatest uncertainty in the LID’s ability to mitigate storm water quality.Interestingly,many of the studies did not recognize the impact of applying a model intended for small-scale processes at a much larger scale for which it is not intended.To explore the ramifications of scale when modelling LIDs in future climates,this paper provides a simple case study of a large catchment on Vancouver Island in British Columbia,Canada,using the Shannon Diversity Index.PCSWMM is used in conjunction with providing regional climates for impacts studies(PRECIS)regional climate model data to determine the relationship between catchment hydrology(with and without LIDs)and the information loss due to PCSWMM’s representation of spatial heterogeneity.The model is applied to five nested catchments ranging from 3 to 51 km2and with an RCP4.5 future climate to generate peak flows and total volumes in 2022,and for the period of 2020–2029.The case study demonstrates that the science behind the LID model within PC stormwater management model(PCSWMM)is too simple to capture appropriate levels of heterogeneity needed at larger-scale implementations.The model actually manufactures artificial levels of diversity due to its landuse representation,which is constant for every scale.The modelling exercise demonstrated that a simple linear expression for projected precipitation vs.catchment area would provide comparable estimates to PCSWMM.The study found that due to the spatial representation in PCSWMM for landuse,soil data and slope,slope(an important factor in determining peak flowrates)had the highest level of information loss followed by soil type and then landuse.As the research scale increased,the normalized information loss index(NILI)value for landuse exhibited the greatest information loss as the catchments scaled up.The NILI values before and after LID implementation in the model showed an inverse trend with the predicted LID mitigating performance. 展开更多
关键词 low impact development climate change stormwater management models stormwater runoff volumes peak flowrates SCALING
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Effect of Low Light on the Characteristics of Photosynthesis and Chlorophyll a Fluorescence During Leaf Development of Sweet Pepper 被引量:23
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作者 SUI Xiao-lei MAO Sheng-li +2 位作者 WANG Li-hao ZHANG Bao-xi ZHANG Zhen-xian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1633-1643,共11页
Low light stress is one of the main limiting factors which influence the production of sweet pepper under protected cultivation in China. In this experiment, two genotypes of sweet pepper, ShY (low light-tolerant gen... Low light stress is one of the main limiting factors which influence the production of sweet pepper under protected cultivation in China. In this experiment, two genotypes of sweet pepper, ShY (low light-tolerant genotype) and 20078 (low light-sensitive genotype), were used to study the effects of low light (photosynthetic photon flux density, PPFD was 75- 100 umol m-2 s-1, control 450-500 umol m-2 s-1) on photosynthesis during leaf development. The result indicated that under low light chlorophyll content, net photosynthetic rate (PN), photosynthetic apparent quantum efficiency (Фi) and carboxylation efficiency (CE) of sweet pepper leaves increased gradually and decreased after reaching the maximum levels. The time to reach the peak values for all the above parameters was delayed, whereas the light compensation point (LCP) decreased gradually along with leaf expansion. The decrease in maximum quantum yield of PS II (Fv/Fm) was not observed at any stages of the leaf development under low light condition, but the actual PS II efficiency under irradiance (ФPS II) was lower accompanied by an increased non-photochemical quenching (NPQ) in young and/or old leaves compared with mature leaves. The antenna thermal dissipation (D) was a main way of heat dissipation when young leaves received excessive light energy, while the decline in photosynthetic function in senescence leaf was mostly owing to the decrease in carbon assimilation capacity, followed by a significantly increased allocation of excessive energy (Ex). Compared with 20078, ShY could maintain higher PN, ФPS II and lower QA reduction state for a longer time during leaf development. Thus, in ShY photosynthetic efficiency and the activity of electron transport of PS II were not significantly affected due to low light stress. 展开更多
关键词 sweet pepper low light photosynthetic efficiency chlorophyll fluorescence leaf development
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Innovation of China's Circular Agricultural Development in the Perspective of Low Carbon Economy 被引量:7
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作者 LI Yan-yan 《Asian Agricultural Research》 2011年第6期5-8,共4页
On the basis of the concept and characteristics of circular economy, this paper analyzes the restraining factors of China's circular agricultural development as follows: issues concerning agriculture, countryside ... On the basis of the concept and characteristics of circular economy, this paper analyzes the restraining factors of China's circular agricultural development as follows: issues concerning agriculture, countryside and farmers are outstanding; the problems of agricultural resources and agricultural ecological environment are serious; the quality of agricultural products cannot meet the demand of domestic and international market for food. Based on the internal requirements of low carbon economic development, this paper advances four innovative models concerning China's circular agricultural development as follows: the model of combining planting and breeding of agriculture, the developmental model of leisure and sightseeing, ecological integration model, and the developmental model of reusing agricultural byproducts. Every region should choose or create different circular agricultural model in different domains, in order to better use agricultural resources, reduce the consumption of agricultural energy inputs, reduce the emission of agricultural greenhouse gas, develop low carbon agriculture, and make great contribution for meeting the international challenges and promoting China's agricultural development. 展开更多
关键词 New village development Circular agriculture low carbon economy China
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Prediction of the Charpy V-notch impact energy of low carbon steel using a shallow neural network and deep learning 被引量:7
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作者 Si-wei Wu Jian Yang Guang-ming Cao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1309-1320,共12页
The impact energy prediction model of low carbon steel was investigated based on industrial data. A three-layer neural network, extreme learning machine, and deep neural network were compared with different activation... The impact energy prediction model of low carbon steel was investigated based on industrial data. A three-layer neural network, extreme learning machine, and deep neural network were compared with different activation functions, structure parameters, and training functions. Bayesian optimization was used to determine the optimal hyper-parameters of the deep neural network. The model with the best performance was applied to investigate the importance of process parameter variables on the impact energy of low carbon steel. The results show that the deep neural network obtains better prediction results than those of a shallow neural network because of the multiple hidden layers improving the learning ability of the model. Among the models, the Bayesian optimization deep neural network achieves the highest correlation coefficient of 0.9536, the lowest mean absolute relative error of 0.0843, and the lowest root mean square error of 17.34 J for predicting the impact energy of low carbon steel. Among the variables, the main factors affecting the impact energy of low carbon steel with a final thickness of7.5 mm are the thickness of the original slab, the thickness of intermediate slab, and the rough rolling exit temperature from the specific hot rolling production line. 展开更多
关键词 PREDICTION shallow neural network deep neural network impact energy low carbon steel
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Low temperature impact toughness and fracture mechanism of cast QT400-18L ductile iron with diferent Ni additions 被引量:2
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作者 Zhang Xinning Qu Yingdong +1 位作者 Yang Hongwang Li Rongde 《China Foundry》 SCIE CAS 2013年第5期310-314,共5页
Different contents of Ni(0.3wt.%to 1.2wt.%)were added to the QT400-18L ductile iron to investigate the effect of Ni addition on the impact toughness of cast ductile irons at low temperatures.The impact toughnesses of ... Different contents of Ni(0.3wt.%to 1.2wt.%)were added to the QT400-18L ductile iron to investigate the effect of Ni addition on the impact toughness of cast ductile irons at low temperatures.The impact toughnesses of the samples at room and low temperatures were tested.The microstructures and fractographs were observed.Results show that with the increase of Ni addition there is a general trend of refinement of the ferrite matrix while the nodule density shows no obvious change.When the Ni content is 0.7wt.%,the matrix structure is the refined ferrite with a very small fraction(about 2%)of pearlite near the eutectic cell boundaries.When the Ni content is further increased,the fraction of pearlite increases significantly and reaches more than 5%when 1.2wt.%Ni is added.The impact toughness at room temperature increases as the content of Ni increases from 0.3 wt.%to 0.7 wt.%,but decreases as the Ni content further increases to 1.2wt.%due to the increase of pearlite fraction.The maximum value of the impact work is 18.5 J at room temperature with 0.7wt.%Ni addition.The average value of the impact work is still more than 13 J even at-30℃.In addition,the fracture mechanism changes from ductile manner to brittleness as the testing temperature decreases from 20℃to-60℃. 展开更多
关键词 NI ductile iron low temperature impact toughness fracture morphology
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Influence of Cr element on impact fracture process of ductile Ni-resistant alloyed iron at low temperature 被引量:1
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作者 Ke Jiang Ying-dong Qu +3 位作者 Jun-hua You Rong-de Li Qing-chun Xiang Yu-xiong Zhou 《China Foundry》 SCIE 2016年第1期42-46,共5页
In this study, in order to investigate the influence of Cr element on the impact fracture process of ductile Ni-resistant alloyed iron at low temperature, different contents of Cr element were added to ductile Ni-resi... In this study, in order to investigate the influence of Cr element on the impact fracture process of ductile Ni-resistant alloyed iron at low temperature, different contents of Cr element were added to ductile Ni-resistant(DNR) austenitic alloyed iron. The experimental results show that Cr addition can increase the hardness of the DNR alloyed iron, but it has an destructive effect on low-temperature impact properties. Through the analysis of the dynamic load and absorbed energy of samples with different Cr contents in the impact fracture process, and the comparison of the impact fracture process at room and low temperatures, it reveals that Cr addition into the DNR alloyed iron can facilitate the formation of the carbide mixture in Mn23C6 and Cr23C6 with homogeneous and discontinuous distribution. Meanwhile, Cr addition also can improve the the maximum dynamic load and crack initiation energy at low temperature, but has no obvious effect on the yield behavior of the DNR alloyed iron in the impact fracture process. Compared with the impact crack propagation process at room temperature, the metastable propagation energy at low temperature declines significantly with an increase in Cr content. This is because the micro-cracks that caused by the carbides weaken the matrix, resulting in the decline of impact crack propagation resistance. The fracture analysis results also show that the impact fracture mechanism gradually transforms from ductile to brittle with an increase in Cr content at low temperature. It explains that too much Cr addition can lead to brittle fracture even though the austenitic matrix has a good toughness at low temperature. 展开更多
关键词 Ni-resistant alloyed iron CARBIDE impact fracture low temperature Cr addition
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Effect of Ti,Zr and Mg addition on inclusions and the impact toughness of heat affected zone in low carbon steel 被引量:1
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作者 JIANG Zhouhua,MA Jianghua,ZHAN Dongping,HE Jicheng and YU Jin School of Materials & Metallurgy,Northeastern University,Shenyang 110004,China 《Baosteel Technical Research》 CAS 2010年第S1期21-,共1页
In order to understand the effects of titanium,zirconium and magnesium on inclusions and the impact toughness of heat affected zone(HAZ) of steel,four low carbon steels deoxidized by titanium,zirconium and magnesium w... In order to understand the effects of titanium,zirconium and magnesium on inclusions and the impact toughness of heat affected zone(HAZ) of steel,four low carbon steels deoxidized by titanium,zirconium and magnesium were obtained.After melting,forging,rolling and welding simulation,the inclusion characteristics (size,distribution,morphology and chemistry) analysis,Charpy-type test and the fracture observation of the specimens after the Charpy-type test were carried out respectively.The following results were found.A linear relationship exists between inclusions density and Ti content when Ti content ranges from 0.004%to 0.032% without Mg,and the proportion of inclusions in diameter less than 0.5μm decreases with the increasing of Ti content in steel.The density of inclusion increases rapidly when adding Ti-Zr-Mg deoxidant.The addition of Ti-Zr-Mg can enhance the impact toughness of HAZ after welding simulation.The maximal impacting energy after welding simulation is 249 J at 253 K.The complex particles of MgO-ZrO_2-TiO_x-MnS are most benefit to enhance impact toughness. 展开更多
关键词 impact toughness HAZ low carbon steel titanium ZIRCONIUM MAGNESIUM
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Effect of Cycling Low Velocity Impact on Mechanical and Wear Properties of CFRP Laminate Composites 被引量:1
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作者 Yang Sun Zhen-Bing Cai +2 位作者 Song-Bo Wu Jian-Hua Liu Jia-Xin Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第6期45-54,共10页
The mechanical and wear properties of CFRP laminate were investigated using a method of cycling low velocity impact, to study the trend and mechanism of impact resistance of the CFRP laminate under repeated impact dur... The mechanical and wear properties of CFRP laminate were investigated using a method of cycling low velocity impact, to study the trend and mechanism of impact resistance of the CFRP laminate under repeated impact during its service process. The interface responses of CFRP laminate under di erent impact kinetic energy during the cycling impact process were studied were studied experimentally, such as impact contact duration, deformation and energy absorption. The worn surface morphologies were observed through optical microscopy and a 3?D surface profiler and the cross?sectional morphologies were observed through SEM to investigate the mechanism of impact material dam?age. Based on a single?degree?of?freedom damping vibration model, the normal contact sti ness and contact damp?ing of the material in di erent wear stages were calculated. It shows the failure process of CFRP laminate damaged by accumulated absorption energy under the cycling impact of di erent initial kinetic energy. The results indicate that the sti ness and damping coe cients will change at di erent impact velocities or cycle numbers. The damage mechanism of CFRP laminates under cycling low kinetic energy is delamination. After repeated experiments, it was found that there was a threshold value for the accumulated absorption energy before the failure of the CFRP laminate. 展开更多
关键词 CFRP laminate low velocity impact impact resistance Accumulated absorption energy threshold DELAMINATION
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Cytological and molecular characteristics of delayed spike development in wheat under low temperature in early spring 被引量:1
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作者 Xurun Yu Yufei Jiang +3 位作者 Huihui Yao Liping Ran Yong Zang Fei Xiong 《The Crop Journal》 SCIE CSCD 2022年第3期840-852,共13页
Low temperature in early spring impairs wheat growth and grain yield.However,little is known about the cytological and molecular mechanisms underlying low temperature regulation of wheat spike development.Microstructu... Low temperature in early spring impairs wheat growth and grain yield.However,little is known about the cytological and molecular mechanisms underlying low temperature regulation of wheat spike development.Microstructure observation and transcriptome sequencing of wheat spikes under low temperature were conducted.Low temperature slowed spike development,reduced the yield-component parameters of wheat spikes at the harvest stage,delayed the formation of lateral spikelets and tissue development,and induced the early differentiation of terminal spikelets.Low temperature increased the content of abscisic acid and caused the upregulation of genes in the abscisic acid signaling pathway,including those encoding PP2 Cs,Sn RK2 s,and b ZIP transcription factors.Low temperature also induced the upregulation of 33 cold-responsive genes involved in wheat response to low-temperature stress and regulation of abscisic acid biosynthesis and metabolism of other substances.The wheat spike adapted to cold conditions by changing the expression levels of genes involved in spike morphogenesis,including the transcription-factor genes MADS6,ERF4,ERF78,WOX6,and NAC48.These findings suggest that low temperature in early spring delays wheat spike development by increasing abscisic acid content or affecting the expression of genes involved in morphogenesis. 展开更多
关键词 development low temperature SPIKE TRANSCRIPTOME WHEAT
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The Use of Prunus mume in the Development of Low Chill Apricot Varieties:the Status of Work in the United States 被引量:1
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作者 David H.Byrne (Department of Horticultural Sciences,Texas A&M University,College Station,TX 77843-2133,Email:d-byrne@tamu.edu) 《北京林业大学学报》 CAS CSCD 北大核心 2003年第S2期15-16,共2页
Several groups in the USA have been working to de-velop a low chill apricot that would ripen its fruits veryearly in the season. Unfortunately, the cultivatcd apricothas been developed mainly from the high chilling Eu... Several groups in the USA have been working to de-velop a low chill apricot that would ripen its fruits veryearly in the season. Unfortunately, the cultivatcd apricothas been developed mainly from the high chilling Euro-pean group within the species Prunus armeniaca. Amongthe five groups within the apricot species, this is the mostrecently evolved and least variable (Bailey and 展开更多
关键词 in on et as for of The Use of Prunus mume in the development of low Chill Apricot Varieties been WORK
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