期刊文献+
共找到945篇文章
< 1 2 48 >
每页显示 20 50 100
The transformation and concentration of environmental hazardous trace elements during coal combustion 被引量:1
1
作者 YAO Duo-xi ZHI Xia-chen 《Journal of Coal Science & Engineering(China)》 2010年第1期74-77,共4页
Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transf... Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transformations and concentration of 18 traceelements during different coal combustion were discussed.The results show that there aresome content distribution of 18 hazardous trace elements in every burnt product, but thelaw of concentration and dispersion of every trace element during different coal combustionis very different.Experiment results indicate that the transformation and concentrationof trace elements during coal combustion are related to the element contents and occur-rencesof trace elements in raw coal, but are also affected by some man-made factorssuch as the combustion method of boiler, combustion temperature and atmosphere, thetype of precipitators and so on. 展开更多
关键词 environmental hazardous trace elements transformation and concentration coal combustion
下载PDF
Recent Development in Simultaneous Multi-Element Determination of the Platinum Group Elements and Gold in Geological and Environmental Samples 被引量:1
2
作者 任曼 邓海琳 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期284-292,共9页
In recent years, the modern methods of multi-element analysis of precious metals have attracted wide attention in scientific research and industry. The application and development in the decomposition of samples, sepa... In recent years, the modern methods of multi-element analysis of precious metals have attracted wide attention in scientific research and industry. The application and development in the decomposition of samples, separation and enrichment, and modern instrumental analysis of the platinum-group elements (PGEs) and gold in geological and environmental samples have been reviewed. Finally, the tendency of analysis of precious metals is also prospected. 展开更多
关键词 铂同组元素 地质环境采样 试金分析法
下载PDF
Variations of nutrient elements and its effect on ecological environment off the Changjiang estuarine waters 被引量:2
3
作者 Lin Yi’ an, Tang Renyou, Pan Jianming, Jin Mingming ( Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第2期197-208,共11页
On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The trans... On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The transform mechanism of present species of nutrients and the of differrnt water masses, frontal area and thermohaline transition layer on convergence or divergence and the biogeochemical cycle of nutrient elements off the Changjiang Estuary are studied. Meanwhile, the environmental capaci- ty of nutrients is primarily estimated: they are 1.803 x 104t DIN and 6.18 x 102t PO43- -P in autumn, and 4.20x 102t PO43- -P in spring. 展开更多
关键词 Nutrient element biogeochemical cycle ecological environmental effect the Changjiang Estuary
下载PDF
Carrying capacity of water environment in public tourism resources based on matter-element model 被引量:6
4
作者 XU Zi-lin YAN Wei 《Ecological Economy》 2016年第3期296-300,共5页
When water environmental carrying capacity of public resource tourist attraction is studied, the two action subjects of tourists and local residents should be discussed, and comprehensive consideration must be given t... When water environmental carrying capacity of public resource tourist attraction is studied, the two action subjects of tourists and local residents should be discussed, and comprehensive consideration must be given to the influence of these two on water environment. On the basis of water resource carrying capacity and water quality carrying capacity, water environmental carrying capacity index of public resource tourist attraction was constructed, the model for the water environmental carrying capacity of public resource tourist attraction was established on the basis of matter-element model and analytical hierarchy process. By applying this method, water environmental carrying capacity situation of a certain public resource tourist attraction can be gained, moreover, situations about several aspects of water environmental carrying capacity can be evaluated. 展开更多
关键词 matter-element model public tourism resources water environmental carrying capacity
下载PDF
Human Exposure Assessment of Element Pollution for Environmental Health Implications: Teeth as a Biomonitoring Tool
5
作者 Athimoolam Sukumar 《Journal of Geoscience and Environment Protection》 2018年第3期37-53,共17页
Reference values reflecting the findings of natural concentrations of teeth in a well-defined group of individuals, are indispensable, if one is to interpret results generated for clinical utility. Hence, a comprehens... Reference values reflecting the findings of natural concentrations of teeth in a well-defined group of individuals, are indispensable, if one is to interpret results generated for clinical utility. Hence, a comprehensive compilation of literature survey is attempted to make available as a reference guideline for tooth element concentrations. Presently, the reference values are proposed for 19 elements. Several factors that are found influencing element levels, are common to any biosample and are broadly grouped under four categories namely, the factors of teeth, donor, environment and analytical methods. How best the influencing factors to be considered during analysis, are discussed. It is elucidated that standardized method of analysis with quality assurance and precision will reduce the ambiguity of comparison of inter-laboratory measurement. When the merits and demerits of element measurements are evaluated, it is recognized that except a hurdle of difficult specific sampling, many advantages make teeth an attractive material for environmental health monitoring of population and for assessment of element status of deficiency and excess due to differential exposure. The available data of tooth elements are lesser in comparison to data of blood and hair;further studies are required for reference values of others elements and for distribution pattern in different conditions, parts and types of teeth. 展开更多
关键词 environmental Health Monitoring elements Human Teeth REFERENCE VALUES element EXPOSURE
下载PDF
Application of closed-vessel microwave digestion method for the determination of multi-elements in environmental samples by sequential ICP-AES
6
作者 Xu Liqiang, Shen Wangxing and Zhu Jingfang Shanghai Institute of Metallurgy,Academia Sinica,Shanghai 200050,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第2期69-75,共7页
A closed-vessel microwave digestion method is described for the rapid dissolution of environmental samples such as foods, soils and sediments. Depending on the sample type, 0.1-0.2 g sample was decomposed with HNO3/H2... A closed-vessel microwave digestion method is described for the rapid dissolution of environmental samples such as foods, soils and sediments. Depending on the sample type, 0.1-0.2 g sample was decomposed with HNO3/H2O2 or HNO3 / H2O2/HF acid mixture in a PTFE digestion vessel by using microwave heating for 2-3 min at 500W of microwave power. The solution, or to which 0.5 g of boric acid was added, was diluted to 25-50 ml and directly determined by sequential ICP-AES. The accuracy of the procedure was validated by the analysis of six standard reference materials for 10 elements. Ail results were in a good agreements with the certified values. 展开更多
关键词 microwave digestion environmental sampl sequential ICP-AES elemental analysis.
下载PDF
Distribution and concentrations of anthropogenic platinum group elements in the surface environment of Hong Kong 被引量:1
7
作者 Nurdan S. Duzgoren-Aydin Steve Edwards +3 位作者 Karen A. Hudson-Edwards Eveline de VOS Adnan Aydin John Malpas 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期108-108,共1页
关键词 白金 元素 地球化学 沉积物 地表环境
下载PDF
Environmental availability and profile characteristics of arsenic, cadmium, lead and zinc in metal-contaminated vegetable soils 被引量:7
8
作者 宋杰 郭朝晖 +2 位作者 肖细元 苗旭锋 王凤永 《中国有色金属学会会刊:英文版》 CSCD 2009年第3期765-772,共8页
Environmental availability and profile characteristics of arsenic (As), cadmium (Cd), lead (Pb) and zinc (Zn) were studied in contaminated vegetable soils from the Pb/Zn mining and smelting areas in Hunan Province of ... Environmental availability and profile characteristics of arsenic (As), cadmium (Cd), lead (Pb) and zinc (Zn) were studied in contaminated vegetable soils from the Pb/Zn mining and smelting areas in Hunan Province of China, and the potential environmental risks of these metals were also assessed. The results show that the concentrations of As, Cd, Pb and Zn in vegetable soils are higher than the levels of Soil Environmental Quality of China (GB15618—1995). The mobility of metals in soil profiles is mainly characterized by the low pH and organic matter content of soil. The major part of As, Cd, Pb and Zn is restricted to the upper soils and the contamination of these metals in soils is significantly influenced by the long-term Pb/Zn mining and smelting activities. Based on the results from the BCR sequential extraction, the fraction of Cd in the soil profiles is predominantly existed in the acid-extractable form and the large amount of Pb is closely associated with reducible fraction. The environmental availability of Cd and Pb is predominantly higher than that of As and Zn in the soil profiles, suggesting Cd and Pb have more huge potential risk for human health and surrounding environment. 展开更多
关键词 土壤环境质量 蔬菜土壤 金属污染 土壤剖面 土壤铅 可用性
下载PDF
Geochemical characteristics of illite clay rocks from the Shihezi Formation in the Hanxing mining area and its sedimentary environment
9
作者 Xu Bohui Ding Shuli +1 位作者 Wang Yu Liu Qinfu 《Mining Science and Technology》 EI CAS 2011年第4期495-500,共6页
We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrome... We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrometry. The results show that the amount of SiO2 is between 53.37% and 61.58% (by weight) and that of Al2O3 22.40% and 31.31% (by weight). The ratio of SiO2/Al2O3 lies between 1.71 and 2.75. The amount of K2O ranges from 1.11% to 2.56% (by weight). The amounts of Fe and Ti are higher than the theoretical values in illite clay rock would indicate. The amounts of some trace elements, such as Ga, As, Ba, Cu, Th and U are higher than their Clark values, while that of another 23 trace elements are found to be dose to their Clark values. The amounts of REE range from 22.59 to 570.54 μg/g, with an average of 163.23μg/g. The ratios of LREE/HREE range from 5.41 to 21.82, with an average of 8.87. These characteristics show that LREE are much richer in content than HREE. The REE distribution patterns of our samples were characterized by clearly negative Ce and Eu anomalies. We analyzed the sedimentary environment of the Hanxing mining area in Late Permian by the characteristic element ratio method. The ratios of Mn/Fe range from 0 to 0.0168, which are lower than those in a marine sedimentary environment. The ratios of Sr/Ba (0.20-0.41) are less than 1. These are all indications that the sediments of the Hanxing mining area in Late Permian form largely a continental sedimentary environment. The sedimentary water is freshwater, a conclusion reached on the basis of the ratios of Th/U (2.66-6.62) and of Ca/(Ca + Fe) (0.01-0.059); the average ratio of Fe2+/Fe3+ is 4.8. The sedimentary water condition is weakly acidic and weakly oxidative-weakly reductive, a conclusion reached on the basis of ratios of Fe2+/Fe3+ (4.8) and of Ceanom (-0.08). 展开更多
关键词 Hanxing mining arealllite Trace elements Geochemical Sedimentary environment
下载PDF
The identification and comparison of the bio-elements of the penguin ornithogenic sediments sample from Davis Station and Great Wall Station
10
作者 黄涛 孙立广 +1 位作者 王玉宏 朱仁斌 《Chinese Journal of Polar Science》 2008年第1期36-44,共9页
During CHINARE-22 in austral summer of 2005-2006, a lake sediment core named DG4, which is impacted by penguin droppings, was retrieved from a lake catchment in Gardner Island of Vestfold Hills, East Antarctica. In th... During CHINARE-22 in austral summer of 2005-2006, a lake sediment core named DG4, which is impacted by penguin droppings, was retrieved from a lake catchment in Gardner Island of Vestfold Hills, East Antarctica. In this study, the concentrations of characteristic elements in the core, local bedrocks and fresh penguin guanos were determined. P, Se, F, S, As, Sr and Cu in DG4 were identified as the bio-element assemblage by R-clustering analysis and compared with those in the local bedrocks and fresh guanos, the results are similar to Y2 in Ardley Island, Antarctic Peninsula. On this basis, P and Se were identified as the optimum bio-elements in DG4 and F, P and S were identified in Y2, respectively. This work will provides the foundation for reconstructing the past penguin populations in Gardner Island of Vest- fold Hills, East Antarctica and comparing the penguin population dynamics between East Antarctica and Antarctic Peninsula. 展开更多
关键词 ornithogenic sediment bio-element environmental background pen-guin diet. Vestfold Hills. Antarctic Peninsula.
下载PDF
Sedimentary Records and Environmental Analysis of the Ximencuo Lake in Northeast Qinghai-Tibet Plateau in the Past 1,700 Years
11
作者 SHEN Defu LI Shijie JIANG Yongjian 《Journal of Landscape Research》 2016年第1期44-48,共5页
Lake sediment is the recorder of historical climate fluctuation and basin environment change. This study collected the Ximencuo Lake sediment in source area of the Yellow River, analyzed organic matters and geochemica... Lake sediment is the recorder of historical climate fluctuation and basin environment change. This study collected the Ximencuo Lake sediment in source area of the Yellow River, analyzed organic matters and geochemical elements of the core, obtained nearly environment changes of the past 1,720 years. The results showed the environment evolution process of the 47-cm columnar core can be divided into four stages: below 32 cm(before 900 A.D.), corresponding to the cool and wet climate; 32–20 cm(900 A.D–1300 A.D.), corresponding to the warming temperature and decreasing precipitation; between 20–3.5 cm(1300–1900 A.D.), the stage is more consistent with the Little Ice Age, and precipitation gradually reduced; 3.5–0 cm(since 1900 A.D.), this is the twentieth Century warming period with increasing temperature and reduced precipitation. Phosphorus content increased rapidly in the last 20 years, reflecting the continuously increasing human interventions, but before this period, the P content was low and stable, indicating the natural background of regional phosphorus content. 展开更多
关键词 The Ximencuo Lake Sediment core element geochemistry environmental change
下载PDF
The System Environment Analysis of Teaching Model for Training English Guides of Stone Inscription Relics
12
作者 李慧 《海外英语》 2018年第2期252-254,共3页
This study proposes a teaching system environment for the training of English guides of stone inscription relics based on analysis and describes the roles played by each element in this system environment. The element... This study proposes a teaching system environment for the training of English guides of stone inscription relics based on analysis and describes the roles played by each element in this system environment. The elements listed in the system environment can contribute themselves only under the support of the whole system environment. Therefore, the effect of the meaning construction is really the coordination result between the elements of the system environment. It can effectively improve the training efficiency of the training of English guides of stone inscription relics. 展开更多
关键词 system environment environment elements teaching model meaning construction
下载PDF
环境法典污染控制制度的二元结构与体系整合 被引量:1
13
作者 刘长兴 柯泉 《西北大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第3期103-112,共10页
污染控制制度是环境法典的最主要内容,需要在现行污染防治单行法律法规的基础上进行体系化整合。现行立法分为两大基本类型,环境要素污染防治法围绕环境要素的污染排除进行制度设计,污染物质和能量污染防治法围绕污染物质和能量的减量... 污染控制制度是环境法典的最主要内容,需要在现行污染防治单行法律法规的基础上进行体系化整合。现行立法分为两大基本类型,环境要素污染防治法围绕环境要素的污染排除进行制度设计,污染物质和能量污染防治法围绕污染物质和能量的减量和管制进行制度设计。在整合进入环境法典污染控制编时,两类污染防治制度的共通性制度要提炼出来进入污染控制编的基本规定,环境要素污染控制制度仍然围绕水、海洋、大气、土壤的污染控制展开,规定与环境要素相对应的具体污染控制制度。污染物质控制制度包括固体废物污染控制、有毒有害物质污染控制和放射性污染控制几个方面,应规定污染物质的全过程管控制度。能量污染控制制度以噪声污染控制为重心,振动、电磁辐射和光辐射污染控制应在法典中有基本规定。在协调不同类型污染控制制度的基础上,对现行污染防治规定进行归类、精简、合并、调整,并补充重要的污染控制规则,以完成环境法典污染控制编的制度设计和编排。 展开更多
关键词 环境法典 污染控制 环境要素 污染物质 制度体系
下载PDF
环境规制、数据要素配置水平与产业结构调整 被引量:7
14
作者 范德成 肖文雪 《统计与决策》 CSSCI 北大核心 2024年第2期105-110,共6页
文章基于数字经济、绿色经济发展深刻影响产业结构转型升级进程这一背景,首先在理论分析的基础上构建了数据要素配置水平综合评价指标体系;然后采用Dagum基尼系数对数据要素配置水平的空间差异及主要来源进行分解测算;最后,基于2012—2... 文章基于数字经济、绿色经济发展深刻影响产业结构转型升级进程这一背景,首先在理论分析的基础上构建了数据要素配置水平综合评价指标体系;然后采用Dagum基尼系数对数据要素配置水平的空间差异及主要来源进行分解测算;最后,基于2012—2019年省级面板数据探讨了环境规制的结构调整红利及数据要素有效配置的渠道效应。研究结果显示,我国数据要素配置水平总体空间差异明显,且区域间差异为主要来源,区域内差异次之。环境规制对产业结构升级存在先促进后抑制的“倒U”型影响,数据要素配置也有显著促进作用。动态边际效应结果显示,在研究期内环境规制所带来的产业结构“调整红利”正在逐渐弱化,数据要素优化配置可充当环境规制促进产业结构升级的有效路径,且从子维度来看,数据传播共享的渠道效应最为显著。数据要素配置的网络外部性特征对环境规制和产业结构优化的调节作用在不同地区所呈现的阶段性特征不同。 展开更多
关键词 环境规制 数据要素配置 Dagum基尼系数 产业结构优化 门槛回归
下载PDF
某FAB厂房结构微振动有限元计算与分析
15
作者 万曦 代剑英 吴芳 《科学技术创新》 2024年第22期173-176,共4页
为研究电子厂房防微振结构设计方法,在对该厂区进行场地环境振动实测后,采用了有限元软件建模计算并分析了半导体厂房结构的微振动水平。结果发现:厂房二层各区域的振动预测均满足微振要求VC-B和VC-C标准;各测点的振动峰值主要集中在2 H... 为研究电子厂房防微振结构设计方法,在对该厂区进行场地环境振动实测后,采用了有限元软件建模计算并分析了半导体厂房结构的微振动水平。结果发现:厂房二层各区域的振动预测均满足微振要求VC-B和VC-C标准;各测点的振动峰值主要集中在2 Hz、12.5 Hz、25 Hz三个频段附近。分析预测结果可为类似的项目提供经验并指导结构设计。 展开更多
关键词 有限元仿真 环境振动 电子厂房
下载PDF
Discrimination of Wild and Hatchery-Reared Black Porgy <i>Acanthopagrus schlegelii</i>Using Otolith Elements Analysis of Magnesium and Manganese
16
作者 Weiche Chang Chunhan Shih +3 位作者 Huangan Lin Chiahui Wang Pinghung Chang Yingchou Lee 《Open Journal of Marine Science》 2019年第1期18-32,共15页
Due to the decreasing resources of both inshore and offshore fisheries, many organizations have released fry to enhance their stock in recent years. The discrimination between wild and hatchery-reared individuals must... Due to the decreasing resources of both inshore and offshore fisheries, many organizations have released fry to enhance their stock in recent years. The discrimination between wild and hatchery-reared individuals must be performed to assess the efficiency of the release. Fresh groundwater is generally used by hatchers in southwesternTaiwanto decrease salinity and to promote the growth of larvae prior to feeding;thus, the elemental composition of the otolith may be different in stocks, and this difference may be used for identification. This study used Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) to analyze the trace elements in the nuclei of otoliths from black porgy Acanthopagrus schlegelii, including six hatchery reared specimens from the Tainan County, three recaptured marked and ten captured unmarked specimens from the Miaoli County in Northwestern coast of Taiwan. Among the six hatchery and three recaptured marked specimens, which ranged from 4.9 to23.4 cmin body length, the nucleus zone (relative to within5 cmin size growth) of the otoliths showed higher magnesium concentrations than that observed on both edges. The distribution was similar to an inverse “V” shape. The otoliths also showed lower manganese concentrations near the nucleus and had higher values near the edges, resulting in a distribution similar to a “U” shape. According to the appeared shape of Mg2+/Ca2+ and Mn2+/Ca2+ ratio in the central area of the nucleus zone, this study determined six specimens which were from hatchery reared and three specimens were from wild among ten unmarked specimens captured from the Northwestern coast of Taiwan. Under the conditions used in this study, the absorption of calcium into the otolith was active and required energy in the seawater and freshwater, while the incorporation of magnesium and manganese was passive and was primarily affected by diffusion. 展开更多
关键词 Black Porgy Hatchery-Reared OTOLITH environmental Growth MARKS Trace element LA-ICPMS
下载PDF
ON THE INFORMATION OF MIRE DEPOSITIONAL ENVIRONMENT
17
作者 马学慧 王荣芬 《Chinese Geographical Science》 SCIE CSCD 1992年第2期70-78,共9页
Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis, 14C dating, mire plant determination for mire ... Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis, 14C dating, mire plant determination for mire sediment, and the study on hierarchy relation of mire sediment, can provide a lot of information for restoring paleogeography, paleoclimate and environmental change. So some people called mire sediment-peat as 'database of environment'. 展开更多
关键词 MIRE SEDIMENT chemical elements ANALYSIS spore-pollen ANALYSIS 14C DATING environmentAL information
下载PDF
寒地滨水公园环境要素对体力活动的影响机理研究--以沈阳市奥林匹克生态公园为例
18
作者 袁敬诚 安天一 周玥琦 《城市学报》 2024年第1期60-66,共7页
城市滨水公园是承载市民体力活动的核心场所,也是促进公共健康的重要媒介。寒地城市气候条件造就了独特的地域滨水环境特征,使环境要素对体力活动的影响呈现一定分异性,因此在寒地城市视域下系统审视与研判滨水公园环境要素对体力活动... 城市滨水公园是承载市民体力活动的核心场所,也是促进公共健康的重要媒介。寒地城市气候条件造就了独特的地域滨水环境特征,使环境要素对体力活动的影响呈现一定分异性,因此在寒地城市视域下系统审视与研判滨水公园环境要素对体力活动的影响具有深刻意义。文章以沈阳市奥林匹克生态公园为例,围绕面域与线域两类空间单元展开探索;建立由空间联系、场地空间、环境质量、基础设施四个方面构成的环境要素体系;结合体力活动与环境要素测度数据,解析环境要素与体力活动密度的关联关系,解析夏、冬两季面域单元与线域单元环境要素对体力活动密度的影响程度及影响差异,并尝试性提出各类环境要素的底线取值标准和适宜取值标准,以期为滨水公园健康效益促升、人居环境品质改善提供有力支持与有效建议。 展开更多
关键词 寒地城市 滨水公园 体力活动密度 环境要素
下载PDF
低碳城市建设能成为企业数字化转型的新动能吗?——来自低碳城市试点的经验证据
19
作者 赵振智 程振 吕德胜 《商业研究》 CSSCI 北大核心 2024年第3期80-91,共12页
数字化转型是企业进行数字技术创新、响应低碳城市试点政策及实现绿色低碳发展的重要路径。本文以低碳城市试点的开展作为“准自然实验”,采用2008-2021年沪深A股上市企业为研究样本,运用多期双重差分模型评估了该政策对企业数字化转型... 数字化转型是企业进行数字技术创新、响应低碳城市试点政策及实现绿色低碳发展的重要路径。本文以低碳城市试点的开展作为“准自然实验”,采用2008-2021年沪深A股上市企业为研究样本,运用多期双重差分模型评估了该政策对企业数字化转型的影响。结果表明:低碳城市试点能够促进试点地区企业数字化转型。机制分析表明,低碳城市试点通过创新能力要素集成、决策制约与治理改善、机会识别驱动等路径促进企业数字化转型。低碳城市试点促进企业数字化转型的结果具有条件异质性,企业ESG软监管绩效评级、公众环境关注度和政府环境关注度对低碳城市试点政策的实施成效存在不同的调节作用。此外,低碳城市试点对企业数字化转型的促进效果对位于高城市数字化环境水平、处于业绩逆差、 CEO具有信息技术背景的企业中更为明显。低碳城市试点产生了促进企业间数字化转型的追赶效应,通过促进企业数字化转型可以推动企业朝着“专精特新”化方式发展。 展开更多
关键词 低碳城市试点 企业数字化转型 创新能力要素 机会识别 环境关注度
下载PDF
黏土矿物-微生物相互作用机理以及在环境领域中的应用
20
作者 董海良 曾强 +12 位作者 刘邓 盛益之 刘晓磊 刘源 胡景龙 李扬 夏庆银 李润洁 胡大福 张冬磊 张文慧 郭东毅 张晓文 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期467-485,共19页
黏土矿物与微生物在自然环境中广泛共存。二者之间的相互作用影响着环境中的能量流动与元素循环。黏土矿物能够给微生物提供物理或化学保护,提高微生物对外界胁迫和干扰的抵抗能力。黏土矿物同时还能给微生物提供营养元素,促进其新陈代... 黏土矿物与微生物在自然环境中广泛共存。二者之间的相互作用影响着环境中的能量流动与元素循环。黏土矿物能够给微生物提供物理或化学保护,提高微生物对外界胁迫和干扰的抵抗能力。黏土矿物同时还能给微生物提供营养元素,促进其新陈代谢过程。黏土矿物中的结构铁是微生物铁氧化还原循环的重要电子供/受体。在氧化还原的环境中,多种铁还原/铁氧化细菌可以通过还原氧化黏土矿物中的结构Fe(Ⅲ)/Fe(Ⅱ),进而获得能量进行生长。在氧化还原过程中,微生物也可以通过溶解、转化、沉淀等作用改变黏土矿物的晶格结构及物相,或是产生新的次生矿物。黏土矿物-微生物相互作用在碳、氮、硅、磷等重要生命元素的地球化学循环中扮演着重要角色。黏土矿物可以通过吸附有机碳,降低有机碳的生物可利用性,减缓其矿化速率。在氧化还原波动的环境中,黏土矿物还可以通过活化分子氧,产生强氧化性自由基氧化降解有机质,提高其生物可利用性。黏土矿物还会吸附生物胞外酶,影响胞外酶降解有机质的效率。微生物通过耦合黏土矿物中铁氧化与硝酸盐还原,铁还原与氨氧化等过程影响氮循环。黏土矿物对磷的吸附以及风化过程中硅的释放影响着微生物的代谢活性。黏土矿物-微生物相互作用在重金属固化稳定、有机污染物降解、杀死病原菌等方面也有广泛的应用。 展开更多
关键词 黏土矿物 微生物 相互作用 元素循环 能量 电子传递 氧化还原 环境治理
下载PDF
上一页 1 2 48 下一页 到第
使用帮助 返回顶部