期刊文献+
共找到384篇文章
< 1 2 20 >
每页显示 20 50 100
Micro Environmental Benefits of Water Resource Tax:Empirical Analysis from the Pilot Project in China(Part One)
1
作者 Wang Qiao Yuan Jiahui 《Belt and Road Initiative Tax Journal》 2025年第1期115-118,共4页
Water scarcity poses a significant challenge in China.While tax has emerged as a crucial policy mechanism for natural resource conservation,empirical evidence of its effectiveness at the firm level remains limited.Thi... Water scarcity poses a significant challenge in China.While tax has emerged as a crucial policy mechanism for natural resource conservation,empirical evidence of its effectiveness at the firm level remains limited.This study investigates the impact of China's pioneering water resource tax reform on corporate environmental performance by analyzing panel data from 456 water-intensive listed companies between 2012 and 2022.Using a difference-in-differences approach,our findings reveal that the introduction of water resource tax significantly enhances firms'environmental performance.Through mediation analysis,we identify green innovation as a key channel through which water resource tax influences environmental performance,with this relationship persisting across various innovation metrics.Our heterogeneity analysis uncovers that the policy's effectiveness varies substantially across firm characteristics:maturer,smaller,non-state-owned,and financially healthier firms exhibit stronger environmental improvements.This research contributes novel micro-level evidence to the environmental regulation literature and offers valuable insights for policymakers in developing economies grappling with water resource management.Our findings suggest that market-based environmental policies can effectively drive corporate environmental responsibility while promoting technological advancement in waterconservation. 展开更多
关键词 Water resource management micro environmental benefit Industrial sustainabletransition Tax policy Waterresourcetax
原文传递
Micro Environmental Benefits of Water Resource Tax:Empirical Analysis from the Pilot Project in China(Part Two)
2
作者 Wang Qiao Yuan Jiahui 《Belt and Road Initiative Tax Journal》 2025年第2期107-118,共12页
3.Methodology and Data 3.1 Baseline Estimation Model To mitigate endogeneity concerns and enhance the rigor of causal inference,this research employs a difference-in-differences(DID)approach to examine the environment... 3.Methodology and Data 3.1 Baseline Estimation Model To mitigate endogeneity concerns and enhance the rigor of causal inference,this research employs a difference-in-differences(DID)approach to examine the environmental performance implications of water resource tax. 展开更多
关键词 difference differences empirical analysis mitigate endogeneity concerns environmental performance implications water resource tax micro environmental benefits baseline estimation model enhance rigor causal inferencethis
原文传递
Analysis of Micro Thermal Environment for Residential District Planning 被引量:1
3
作者 ZHANG Wei-jie QI Jing JIN Wen 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期51-54,共4页
This paper focused on residential district planning process.Using GIS and SketchUp software,a common digital relief map model of a residential district was created,and the air distribution(both velocity and temperatur... This paper focused on residential district planning process.Using GIS and SketchUp software,a common digital relief map model of a residential district was created,and the air distribution(both velocity and temperature)within this residential district was established by CFD simulation.So,the velocity and temperature of the air at any location within the residential district,as well as the worse flow area and overheat area can be clearly presented.An index of micro thermal environment for the air distribution evaluation was established.Depending on a certain residential district planning model,from the air parameters of the micro environment at any location within the residential district,such as air velocity and air temperature,the index of micro thermal environment was obtained by certain principles and data processing process.By this index,the residential district planning scheme was evaluated corresponding to the thermal characteristics of the residential district.If this index is not good enough or unsatisfied,the residential district planning idea and process can be changed or improved accordingly in order to get a better thermal characteristics of the residential district judged by the established evaluation index system. 展开更多
关键词 residential district planning micro thermal environment micro thermal environmental index CFD SKETCHUP
在线阅读 下载PDF
Study on the Promotion Strategy of College Students’ Reading and Writing Ability Under the Micro Network Environment
4
作者 LIU Xiao-zheng LIU Jin-feng 《Sino-US English Teaching》 2018年第6期317-324,共8页
Network media has become more and more involved in our daily life. It has become a part of modern life that cannot be stopped or rejected. Then, how to correctly face the changes in the Internet era is placed in fron... Network media has become more and more involved in our daily life. It has become a part of modern life that cannot be stopped or rejected. Then, how to correctly face the changes in the Internet era is placed in front of everyone. Students need to “learn how to use the media to get their all-round development, effectively prevent the foreign information pollution, and actively guide students to a truly rational attitude for WeChat, blog and micro-blog”. It is a kind of media literacy being confronted with the network’s ability to consciously resist the harmful information, but also to benefit their own development and firmly grasp the information, so as to make full use of the convenience of network self promotion. “Screen reading” network plays an important role in college students’ life, and the fragmentation, the text features of the writing ability of college students also have a strong impact; this paper focuses on the influence of college students in the network reading and writing patterns on their writing ability and influence. From the perspective of media literacy education for college students, writing ability and reading ability provide a feasible way. 展开更多
关键词 reading ability writing ability college students micro network environment
在线阅读 下载PDF
Effects of micro-environmental conditions and forest disturbance on the establishment of two Andean palms in Ecuador
5
作者 Diana Rodríguez-Paredes Rommel Montúfar-Galárraga Henrik Meilby 《Open Journal of Ecology》 2012年第4期233-243,共11页
The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore ... The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests. 展开更多
关键词 Andean FOREST Ceroxylon FOREST DISTURBANCE micro-environmental VARIABLES PALM ESTABLISHMENT Prestoea Sustainable Management
暂未订购
Micro-environmentally Restricted Yeast Cell Growth within Ca-alginate Microbeads
6
作者 Ivana Pajic-Lijakovic Branko Bugarski +4 位作者 Branko Bugarski Milenko Plavsic Steva Levic Ana Kalusevic Viktor Nedovic 《Engineering(科研)》 2012年第10期180-183,共4页
Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellula... Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellular clusters, (2) forces generated by cell growth inside the beads and (3) interactions between solvent, network parts and cells. The resulting effects are measured experimentally by estimating volume of microbeads and yeast cell concentration as function of time of cultivation. Comparative analysis of dynamics of cell growth and increase of microbead volume through four regimes indicates that reversible and irreversible local structural changes of Ca-alginate hydrogel induces micro-environmental restrictions to cell growth. The mechanism of restrictions includes both mechanical and electrostatic effects. 展开更多
关键词 YEAST Cells micro-environmental Restrictions CA-ALGINATE Hydrogel Matrix Structural Changes Pattern of VOLUMETRIC YEAST GROWTH
暂未订购
臭氧微纳米气泡技术在环境治理领域的研究进展
7
作者 杨静雯 刘松涛 +1 位作者 黄应清 陈传敏 《化工设计通讯》 2026年第1期91-94,共4页
臭氧微纳米气泡技术作为近年来环境领域的重要创新,通过结合臭氧的强氧化性与微纳米气泡的独特理化性质,有效克服了传统臭氧氧化技术的局限性。文章系统综述了臭氧微纳米气泡技术的作用机理、在各类环境领域中的应用进展以及未来发展方... 臭氧微纳米气泡技术作为近年来环境领域的重要创新,通过结合臭氧的强氧化性与微纳米气泡的独特理化性质,有效克服了传统臭氧氧化技术的局限性。文章系统综述了臭氧微纳米气泡技术的作用机理、在各类环境领域中的应用进展以及未来发展方向,旨在为研究人员全面了解臭氧微纳米气泡技术的最新进展提供参考,并为该技术的进一步优化与推广应用提供思路。 展开更多
关键词 臭氧微纳米气泡 微纳米气泡 应用 环境污染控制 特性
在线阅读 下载PDF
三种典型白酒环境微生物群落结构解析、酿造微生物溯源及功能特性
8
作者 唐家环 岳松 +1 位作者 张庆 潘强林 《中国酿造》 北大核心 2026年第1期13-20,共8页
浓香型、酱香型、大曲清香型作为3种典型白酒,均以粮谷为原料,大曲为糖化发酵剂在开放的环境中进行生产而成的蒸馏酒。开放式的生产模式使得3种典型白酒受环境微生物的影响不容忽视,随着扩增子测序、宏基因组学等技术的发展,环境微生物... 浓香型、酱香型、大曲清香型作为3种典型白酒,均以粮谷为原料,大曲为糖化发酵剂在开放的环境中进行生产而成的蒸馏酒。开放式的生产模式使得3种典型白酒受环境微生物的影响不容忽视,随着扩增子测序、宏基因组学等技术的发展,环境微生物对白酒酿造微生态的影响逐渐被深入探究。该文综述了3种典型白酒环境微生物群落分析方法、群落结构解析及其影响因素,对白酒酿造微生物进行溯源分析,并概述了酿造微生物的功能特性,旨在为解析发酵环境微生物种群结构,探讨环境微生物对白酒发酵过程的影响及塑造有利于白酒发酵的环境微生态提供参考。 展开更多
关键词 白酒 发酵 微生态 环境微生物 酿造微生物 溯源分析 功能特性
在线阅读 下载PDF
露天矿山环境治理中微地形复绿技术研探——以河北省滦州市椅子山示范区治理为例
9
作者 于帅 李万增 +1 位作者 夏慧洁 周颖 《黑龙江环境通报》 2026年第1期101-103,共3页
本文结合“燕山地区碳酸盐岩高陡边坡生态修复技术攻关与试验”项目,针对矿山微地形边坡治理,创新性提出“悬垂绿化”“锚杆套管”生态修复技术,在露天矿山椅子山综合治理试验区进行露天矿山生态修复技术攻关与试验。通过工程措施与植... 本文结合“燕山地区碳酸盐岩高陡边坡生态修复技术攻关与试验”项目,针对矿山微地形边坡治理,创新性提出“悬垂绿化”“锚杆套管”生态修复技术,在露天矿山椅子山综合治理试验区进行露天矿山生态修复技术攻关与试验。通过工程措施与植被恢复相结合的方法,对覆绿技术实施效果进行定期调查观测,并结合试验数据对微地形复绿技术的实施工艺、植被成活率、植被复绿效果等方面进行应用分析,以期丰富露天矿山生态修复治理技术方法,为今后同类型的矿山地质环境治理项目提供有力的技术支持。 展开更多
关键词 露天矿山 环境治理 微地形 复绿技术
在线阅读 下载PDF
水环境中微塑料与共污染物相互作用机制研究进展
10
作者 张力薇 罗志雄 +1 位作者 陆健刚 龚梓逸 《江西水利科技》 2026年第1期25-32,57,共9页
水环境中微塑料的广泛存在及其作为共污染物载体的潜在风险,正引发广泛关注。微塑料可通过静电吸附、疏水相互作用、氢键、π–π作用等机制与重金属、有机污染物、抗生素抗性基因等形成复杂复合污染体系,进而改变污染物的迁移转化行为... 水环境中微塑料的广泛存在及其作为共污染物载体的潜在风险,正引发广泛关注。微塑料可通过静电吸附、疏水相互作用、氢键、π–π作用等机制与重金属、有机污染物、抗生素抗性基因等形成复杂复合污染体系,进而改变污染物的迁移转化行为、生物可利用性与生态毒性。微塑料理化性质、环境因子与水动力过程等多因素共同调控其协同效应,机制间常呈现显著耦合性和非线性响应趋势。文章梳理了微塑料与共污染物的主要相互作用机制,比较了不同污染物类型的行为特征,归纳了影响机制的关键因素,并评述了具体的研究手段,旨在为水环境污染风险识别与治理策略制定提供机制基础与理论参考。 展开更多
关键词 污染物协同迁移 吸附机制 环境影响因子 分子模拟 微界面过程
在线阅读 下载PDF
Nanostructured Ternary Metal Tungstate-Based Photocatalysts for Environmental Purification and Solar Water Splitting:A Review 被引量:10
11
作者 Jun Ke M.Adnan Younis +4 位作者 Yan Kong Hongru Zhou Jie Liu Lecheng Lei Yang Hou 《Nano-Micro Letters》 SCIE EI CAS 2018年第4期201-227,共27页
Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including ... Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including low cost,eco-friendliness, and high stability under acidic and oxidative conditions. However, rapid recombination of photoinduced electron–hole pairs and a narrow light response range to the solar spectrum lead to low photocatalytic activity of MWO_4-based materials, thus significantly hampering their wide usage in practice. To enable their widespread practical usage, significant efforts have been devoted, by developing new concepts and innovative strategies. In this review, we aim to provide an integrated overview of the fundamentals and recent progress of MWO_4-based photocatalysts. Furthermore, different strategies, including morphological control, surface modification, heteroatom doping, and heterojunction fabrication, which are employed to promote the photocatalyticactivities of MWO_4-based materials, are systematically summarized and discussed. Finally, existing challenges and a future perspective are also provided to shed light on the development of highly efficient MWO_4-based photocatalysts. 展开更多
关键词 Ternary metal tungstates micro- and nanostructures PHOTOCATALYSIS environmental purification Water splitting
在线阅读 下载PDF
Micro Seasonal Fashion Impact in RMG Industry of Bangladesh
12
作者 Mohammed Shamsul Alam Md. Ahshan Habib +3 位作者 Nabinur Rahman Adnan Arifin Himel Md. Yeasin Ullah Resvy Mohammad Mainul Hasan 《Journal of Textile Science and Technology》 2023年第4期258-272,共15页
The Ready-Made Garments (RMG) industry is a major contributor to the economy of Bangladesh, accounting for over 80% of the country’s total exports. In recent years, the industry has faced challenges due to changing g... The Ready-Made Garments (RMG) industry is a major contributor to the economy of Bangladesh, accounting for over 80% of the country’s total exports. In recent years, the industry has faced challenges due to changing global fashion trends and increasing competition from other manufacturing countries. One of the latest trends in the fashion industry is micro seasonal fashion, which has significant impacts on the RMG industry of Bangladesh. The purpose of this study is to examine the impact of micro seasonal fashion on the RMG industry of Bangladesh. It will examine the changes in buyer and consumer behavior and demand patterns, the implications for manufacturers and suppliers, and the strategies adopted by industry players to adapt to this trend. The emergence of micro seasonal fashion has disorderly the traditional seasonal cycle of the fashion industry. Consumers are no longer satisfied with the two-season model of spring/summer and fall/winter, but instead demand new styles and trends every few weeks. This trend has created opportunities for the RMG industry of Bangladesh to cater to the fast-changing demands of consumers. Micro Seasonal Fashion also poses significant challenges for the industry. Manufacturers and suppliers must be able to produce and deliver garments quickly and efficiently, while ensuring high quality and sustainability standards. This requires investments in technology, supply chain management, and training of workers. To address these challenges, industry players in Bangladesh have adopted several strategies, such as diversifying product offerings, investing in technology and innovation, and enhancing sustainability practices. These strategies have helped the industry to remain competitive and meet the demands of fast-changing consumer preferences. The industry must be able to adapt quickly to the changing demands of consumers and invest in technology and sustainability practices to remain competitive. With the right strategies and investments, the RMG industry of Bangladesh can control the opportunities presented by micro seasonal fashion and continue to be a major player in the global fashion industry. 展开更多
关键词 micro-Session environmental RMG Consumers Demand Fashion Impact
在线阅读 下载PDF
个性特质与群体共相:弘扬教育家精神的内在机理与实践张力
13
作者 陈晓雨 王磊 《教育理论与实践》 北大核心 2026年第4期3-10,共8页
以教育家精神引领高素质教师队伍建设,有力支撑基础教育扩优提质,是教育强国建设进程中必须回答好的时代命题。教育家精神是教师队伍“群体共相”与教师个体“个性特质”的辩证统一。从理念提炼历程来看,“教育家精神”是从教育家和优... 以教育家精神引领高素质教师队伍建设,有力支撑基础教育扩优提质,是教育强国建设进程中必须回答好的时代命题。教育家精神是教师队伍“群体共相”与教师个体“个性特质”的辩证统一。从理念提炼历程来看,“教育家精神”是从教育家和优秀教师的“个性特质”中逐步抽象概括出来,并被期待能够为广大教师普遍展现的“群体共相”;从实践生成过程来看,弘扬教育家精神旨在把这一理想的“群体共相”转化并融入每个教师现实的“个性特质”中,实现广大教师精神境界的丰富与提升。个性特质与群体共相的交织转化构成了弘扬教育家精神的基本主线,并在这一过程中延展出宏大叙事与微观实践、共性涌现与个性彰显、环境塑造与主体建构、群体共生与少数引领等多维张力结构。弘扬教育家精神需以系统思维准确把握这些张力关系,在动态平衡中形成统一进路。 展开更多
关键词 个性特质 群体共相 教育家精神 宏大叙事 微观实践 共性涌现 个性彰显 环境塑造 主体建构
在线阅读 下载PDF
原位Fenton耦合微纳米气泡降解酸性矿山废水有机物特性研究 被引量:2
14
作者 杨超 李福星 +4 位作者 杨丽静 武栋平 杨亮亮 李丹 卜显忠 《安全与环境学报》 北大核心 2025年第2期706-713,共8页
针对酸性矿山废水(Acid Mine Drainage,AMD)中有机物威胁生态环境的问题,研究基于AMD自身呈酸性和Fe^(2+)含量高的特点,仅在外加H_(2)O_(2)和微纳米气泡(Micro Nano Bubbles,MNBs)的条件下构建原位Fenton耦合MNBs(FT+MNBs)反应体系,以处... 针对酸性矿山废水(Acid Mine Drainage,AMD)中有机物威胁生态环境的问题,研究基于AMD自身呈酸性和Fe^(2+)含量高的特点,仅在外加H_(2)O_(2)和微纳米气泡(Micro Nano Bubbles,MNBs)的条件下构建原位Fenton耦合MNBs(FT+MNBs)反应体系,以处理AMD中的有机物。此外,对反应时间、Fe^(2+)与H2O_(2)物质的量比、pH值、进气流量等操作条件进行优化,并探究体系对有机物的去除效果及机理。结果显示:当反应时间为15 min,Fe^(2+)与H_(2)O_(2)物质的量比为1∶7,pH值为4,进气流量为60 mL/min时,原位FT+MNBs对AMD中总有机碳(Total Organic Carbon,TOC)的去除率为66.03%。通过机理分析可知,原位Fenton耦合MNBs体系对类溶解性微生物代谢产物的降解效果明显优于单独原位FT和单独MNBs,原因在于原位Fenton耦合MNBs体系可以产生更多的·OH,并将有机物中的C—C、C—H、C—N以及C—O键断裂,增加C—O、O—CO等含氧官能团含量,进而将其进一步分解后矿化为CO_(2)和H_(2)O后去除。 展开更多
关键词 环境工程学 芬顿 微纳米气泡 酸性矿山废水 有机物
原文传递
Structure Characterization and Dephosphorization Effect Analysis of Oyster Shell-silica Micropowder Waste Water Dephosphorization Materials 被引量:2
15
作者 赖寿莲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第1期33-38,共6页
In this work,the effects of pH value of waste water and initial concentration of phosphorus on dephosphorization materials were investigated.The materials were prepared by shaping,sintering and hydrothermal reshaping ... In this work,the effects of pH value of waste water and initial concentration of phosphorus on dephosphorization materials were investigated.The materials were prepared by shaping,sintering and hydrothermal reshaping oyster shell and silica micro-powder.Different concentrations of phosphorus-contained waste water were simulated with potassium dihydrogen phosphate solution,the effect of dephosphorization was tested with phosphomolybdenum blue spectrophotometer method,and the crystal phase and microstructure of materials were characterized by XRD and SEM methods. It was indicated that dephosphorization was completed in 6 h when the initial phosphorus concentration in waste water was lower than 15 mg/L, and the dephosphorization time prolonged as the increase of phosphorus concentration. It was observed that the pH value of waste water influenced dephosphorization significantly, and neutral subalkalic environment favored dephosphorization. When the pH value was 11, the efficiency of dephosphozation was the greatest. For waste water with an initial concentration of 20 mg/L, the dephosphozation rate is close to 100% in8 h. 展开更多
关键词 oyster shell silica micro-powder hydrothermal reaction waste water dephosphorization materials environmental-friendly material
在线阅读 下载PDF
太阳能耦合微型燃气轮机联合循环系统性能
16
作者 张小桃 王琪贤 +1 位作者 李可欣 王爱军 《洁净煤技术》 北大核心 2025年第5期145-153,共9页
太阳能耦合燃气轮机发电能够提高燃气轮机联合循环系统的运行性能。搭建了微型燃气轮机联合循环模型,并基于C200型微型燃气轮机的设计数据,以天然气为燃料,验证模型的合理性。在联合循环系统的基础上,增加了太阳能集热器,选取天然气和... 太阳能耦合燃气轮机发电能够提高燃气轮机联合循环系统的运行性能。搭建了微型燃气轮机联合循环模型,并基于C200型微型燃气轮机的设计数据,以天然气为燃料,验证模型的合理性。在联合循环系统的基础上,增加了太阳能集热器,选取天然气和沼气为燃料,研究集热器布置位置与环境条件变化对太阳能耦合燃气轮机联合循环系统运行性能的影响。结果表明:在机组相同输出功率条件下,无集热器的沼气系统与天然气系统相比,燃料流量增大了近1倍,但燃气流量差别较小,联合循环系统性能接近,燃气轮机电效率约为30%,余热效率达到33%。加装太阳能集热器可以减小燃料流量,提高机组运行性能。集热器前置时系统的电效率稍有增加,而余热效率升高到50%以上;集热器后置时,燃料流量明显减小,而电效率可达到39%以上,余热效率达到42%。在相同的输出功率条件下,随着太阳辐射强度和环境温度的变化,天然气和沼气系统,在10时到12时之间,系统性能最好,燃料流量最大减少了39.48%、37.88%,电效率最多提高了19.41%、17.91%,余热效率最多提高了40.13%、40.16%。集热器前置时系统余热量增加较多;集热器后置时燃气轮机电效率升高较多,同时余热量也有增加。 展开更多
关键词 微型燃气轮机 沼气 太阳能集热器 环境条件 系统性能
在线阅读 下载PDF
水杨酸分子印迹聚合物整体柱合成及其固相微萃取应用
17
作者 王岩 《化肥设计》 2025年第1期36-39,共4页
以水杨酸为模板、4-乙烯吡啶为单体,通过原位聚合(遵循模板分子∶功能单体∶交联剂=1∶4∶18)合成新型高分子材料,并用于色谱柱填充,实现高效固相微萃取。经细致优化萃取参数,构建了高效液相微萃取联用技术,该技术检测下限为1.2 ng/mL,... 以水杨酸为模板、4-乙烯吡啶为单体,通过原位聚合(遵循模板分子∶功能单体∶交联剂=1∶4∶18)合成新型高分子材料,并用于色谱柱填充,实现高效固相微萃取。经细致优化萃取参数,构建了高效液相微萃取联用技术,该技术检测下限为1.2 ng/mL,回收率为92.1%~105.8%,操作简便,选择性高。实验证明:本法灵敏度高,适用于环境样品中水杨酸测定,为相关研究与监测提供有力支持。通过精确调控溶液体积、pH值、去垢剂种类与用量及萃取速度,确保了技术的准确性和可靠性。 展开更多
关键词 水杨酸 固相微萃取 环境水
在线阅读 下载PDF
微锥型滤筒清灰性能研究与优化
18
作者 林龙沅 赵云菲 +2 位作者 朱广春 朱炫昱 庞浩 《安全与环境学报》 北大核心 2025年第11期4437-4445,共9页
为了提高真空上料机微锥型滤筒的清灰均匀性,优化微锥型滤筒清灰性能,研究开展了不同喷吹孔径、喷吹压力、喷吹距离和喷吹型式等多喷吹参数的冷态脉冲喷吹试验,并以微锥型各个部分测得的侧壁压力峰值作为评价喷吹性能的指标,系统分析了... 为了提高真空上料机微锥型滤筒的清灰均匀性,优化微锥型滤筒清灰性能,研究开展了不同喷吹孔径、喷吹压力、喷吹距离和喷吹型式等多喷吹参数的冷态脉冲喷吹试验,并以微锥型各个部分测得的侧壁压力峰值作为评价喷吹性能的指标,系统分析了喷吹参数对微锥型滤筒清灰效果的影响。研究结果显示:随着喷吹距离的增加,锥型滤筒上部侧壁的压力峰值增大,清灰效果获得改善。随着喷吹压力的增加,锥形滤筒整体侧壁压力峰值增大,但降低了喷吹压力峰值分布的均匀性,增大了滤筒损伤的风险。与12 mm喷吹口径相比,15 mm喷吹口径能够提高40%喷吹侧壁压力峰值,尤其对滤筒上部清灰效果改善明显,但其清灰均匀性会降低74%。相比于直管喷吹,采用涡旋喷吹时的锥型滤筒的清灰均匀性显著提升50%以上,粉尘残余量均匀性提升了22%。考虑到能耗和滤筒损耗因素,涡旋喷吹对微锥型滤筒清灰是一个更经济实用的选择。 展开更多
关键词 环境工程学 微锥型滤筒 喷吹孔 孔径 侧壁压力峰值
原文传递
塑料老化过程及其环境危害研究进展 被引量:2
19
作者 杨妮娜 左剑恶 +1 位作者 张艳艳 门聪 《环境科学》 北大核心 2025年第3期1850-1860,共11页
塑料污染已成为全球性的环境问题,对生态系统和人类健康构成了显著威胁.塑料老化是一个持续的动态过程,此过程中会有各种尺寸级别的塑料产生与存在,如:大型塑料、微塑料及纳米塑料.无论哪个尺寸级别的塑料,其都会持续破碎并释放塑料添... 塑料污染已成为全球性的环境问题,对生态系统和人类健康构成了显著威胁.塑料老化是一个持续的动态过程,此过程中会有各种尺寸级别的塑料产生与存在,如:大型塑料、微塑料及纳米塑料.无论哪个尺寸级别的塑料,其都会持续破碎并释放塑料添加剂及其他溶解性产物.此外,由于分子组成与结构相同,微纳米塑料与宏观塑料的老化机制及呈现的老化特性相似,但颗粒的尺寸越小危害越大.为加深对塑料环境效应的了解,聚焦于塑料从初始形态到老化降解的整个动态过程,综述了塑料在此过程中所涉及的老化机制、特性变化及释放产物.以上产物包括大型塑料、微纳米塑料、塑料添加剂及其他溶解性产物.同时,归纳了塑料老化实验的相关研究及主要结论,并进一步探讨了影响塑料添加剂浸出和微纳米颗粒释放的因素.最后,总结了塑料老化产物可能造成的环境危害. 展开更多
关键词 塑料 老化 环境危害 微纳米塑料 添加剂
原文传递
LPCVD制备二氧化硅薄膜工艺中防颗粒污染技术 被引量:1
20
作者 樊坤 黄志海 +2 位作者 王理正 王志伟 苏子懿 《电子工艺技术》 2025年第2期52-55,共4页
二氧化硅(SiO_(2))薄膜制备作为集成电路制造工艺中重要的一个步骤,在芯片的制造过程中具有多种用途,但易受颗粒污染造成产品不良。对采用TEOS源LPCVD法沉积SiO_(2)膜颗粒污染的方法进行了探索,设计了一种用于防颗粒污染的机构,该机构... 二氧化硅(SiO_(2))薄膜制备作为集成电路制造工艺中重要的一个步骤,在芯片的制造过程中具有多种用途,但易受颗粒污染造成产品不良。对采用TEOS源LPCVD法沉积SiO_(2)膜颗粒污染的方法进行了探索,设计了一种用于防颗粒污染的机构,该机构主要包括微环境系统和温度控制系统,重点介绍了立式LPCVD设备工艺颗粒来源、微环境系统和温度控制系统结构组成,以及微环境系统和温度控制系统的应用效果。 展开更多
关键词 半导体 CVD 温度控制 微环境 颗粒污染 二氧化硅
在线阅读 下载PDF
上一页 1 2 20 下一页 到第
使用帮助 返回顶部