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281.
伴随生态文明建设确立为国家战略,环境规制与绿色创新日益成为学术领域研究的热点,其中最具代表性的波特假说近年来逐渐成为多领域学者们关注的重点问题,并积累了丰硕的研究成果。本文以1995—2018年Web of Science数据库中波特假说领域相关研究的文献为样本,运用可视化分析软件,基于点-线-面三维框架整理了环境规制与绿色创新、竞争力等相关主题的关键文献、历史路径和关键词聚类等内容。首先,在关键词共被引网络分析的基础上探讨波特假说研究中存在的四个热点方向,即学者们热衷于对波特假说的强版本、狭义版本以及弱版本进行检验;学者们对环境政策的研究细分至具体的政策如能源政策;倾向于利用不同类型的环境规制对企业环境创新进行验证;探究环境规制和环境创新成因之间的关系。接着,运用文献共被引关系路径分析发现两种引证关系路径,即实证引证关系路径和理论引证关系路径。最后,通过对高被引文献的共被引关系进行模块化分析,显示出了五个重要热点聚类:环境绩效与财务绩效;环境管制与竞争力;企业环境行为与环境管理;环境管制与产业区位选择;环境管制与生产效率。从而,得出了未来需要加强波特假说研究的五个方向的建议:一是文献研究对象需要扩展比较,理论支撑有待继续挖掘;二是针对企业异质性进行环境政策特性设计,灵活创新政府政策工具;三是企业主动性加强,推动形成企业层面研究新视角;四是关注跨国贸易,强化环境规制对国际碳转移和污染倾销问题研究;五是拓宽研究方法的新视角,多关注政策工具间交互影响。 相似文献
282.
Eric D. Crandall Rachel H. Toczydlowski Libby Liggins Ann E. Holmes Maryam Ghoojaei Michelle R. Gaither Briana E. Wham Andrea L. Pritt Cory Noble Tanner J. Anderson Randi L. Barton Justin T. Berg Sofia G. Beskid Alonso Delgado Emily Farrell Nan Himmelsbach Samantha R. Queeno Thienthanh Trinh Courtney Weyand Andrew Bentley John Deck Cynthia Riginos Gideon S. Bradburd Robert J. Toonen 《Conservation biology》2023,37(4):e14061
Genetic diversity within species represents a fundamental yet underappreciated level of biodiversity. Because genetic diversity can indicate species resilience to changing climate, its measurement is relevant to many national and global conservation policy targets. Many studies produce large amounts of genome-scale genetic diversity data for wild populations, but most (87%) do not include the associated spatial and temporal metadata necessary for them to be reused in monitoring programs or for acknowledging the sovereignty of nations or Indigenous peoples. We undertook a distributed datathon to quantify the availability of these missing metadata and to test the hypothesis that their availability decays with time. We also worked to remediate missing metadata by extracting them from associated published papers, online repositories, and direct communication with authors. Starting with 848 candidate genomic data sets (reduced representation and whole genome) from the International Nucleotide Sequence Database Collaboration, we determined that 561 contained mostly samples from wild populations. We successfully restored spatiotemporal metadata for 78% of these 561 data sets (n = 440 data sets with data on 45,105 individuals from 762 species in 17 phyla). Examining papers and online repositories was much more fruitful than contacting 351 authors, who replied to our email requests 45% of the time. Overall, 23% of our email queries to authors unearthed useful metadata. The probability of retrieving spatiotemporal metadata declined significantly as age of the data set increased. There was a 13.5% yearly decrease in metadata associated with published papers or online repositories and up to a 22% yearly decrease in metadata that were only available from authors. This rapid decay in metadata availability, mirrored in studies of other types of biological data, should motivate swift updates to data-sharing policies and researcher practices to ensure that the valuable context provided by metadata is not lost to conservation science forever. 相似文献
283.
Claire A. Runge Ayesha I. T. Tulloch Ascelin Gordon Jonathan R. Rhodes 《Conservation biology》2017,31(6):1428-1438
The proliferation of linear infrastructure such as roads and railways is a major global driver of cumulative biodiversity loss. One strategy for reducing habitat loss associated with development is to encourage linear infrastructure providers and users to share infrastructure networks. We quantified the reductions in biodiversity impact and capital costs under linear infrastructure sharing of a range of potential mine to port transportation links for 47 mine locations operated by 28 separate companies in the Upper Spencer Gulf Region of South Australia. We mapped transport links based on least‐cost pathways for different levels of linear‐infrastructure sharing and used expert‐elicited impacts of linear infrastructure to estimate the consequences for biodiversity. Capital costs were calculated based on estimates of construction costs, compensation payments, and transaction costs. We evaluated proposed mine‐port links by comparing biodiversity impacts and capital costs across 3 scenarios: an independent scenario, where no infrastructure is shared; a restricted‐access scenario, where the largest mining companies share infrastructure but exclude smaller mining companies from sharing; and a shared scenario where all mining companies share linear infrastructure. Fully shared development of linear infrastructure reduced overall biodiversity impacts by 76% and reduced capital costs by 64% compared with the independent scenario. However, there was considerable variation among companies. Our restricted‐access scenario showed only modest biodiversity benefits relative to the independent scenario, indicating that reductions are likely to be limited if the dominant mining companies restrict access to infrastructure, which often occurs without policies that promote sharing of infrastructure. Our research helps illuminate the circumstances under which infrastructure sharing can minimize the biodiversity impacts of development. 相似文献
284.
Carmen E. Carrión-Flores Robert Innes Abdoul G. Sam 《Journal of Environmental Economics and Management》2013
We study whether a government-sponsored voluntary pollution reduction program (VPR) promotes or deters the development of new environmental technologies that yield future emission reduction benefits. Using a panel of 127 U.S. manufacturing industries defined by 3-digit SIC classifications over the 1989–2004 period, we estimate impacts of industry-level participation in the 33/50 program, a VPR initiated by government regulators in 1991, on industry-level rates of environmental patenting. We find that higher rates of 33/50 program participation are associated with significant reductions in the number of successful environmental patent applications five to nine years after the program ended. 相似文献
285.
P.S. Akhil 《毒物与环境化学》2013,95(9):1718-1725
The Kasargod District is the northernmost district of Kerala State and is bound between the north latitudes 12°02′27″ and 12°47′35″ and east longitudes 74°51′54″ and 75°25′25″. The present study highlights the contamination levels of organochlorine pesticides in open wells of the Kasargod District from 2010 to 2011. Maximum contamination of organochlorine pesticides (OCP's) was observed for endosulfan followed by hexachlorobenzene (BHC). Contamination levels of α-endosulfan were higher at Panathur (58?µg?L?1) and next to Periya (37?µg?L?1) in the postmonsoon season of 2010. During premonsoon 2011, the residue levels of α-endosulfan were higher at Panathady (56?µg?L?1) followed by Rajapuram (40?µg?L?1). Contamination levels of the BHC isomers exhibit the order of γ-BHC?>?α-BHC?>?β‐BHC, showing that γ-BHC represents 62% of the total OCP residues in premonsoon 2010. Among the studied OCP's, concentration levels of DDT were below detection limit. Maximum concentrations of the sum of all OCP residues were observed at Mulleria and Cheemeni (premonsoon 2010), followed by Panathur and Periya (postmonsoon 2010), and lowest in Panathady and Rajapuram (premonsoon 2011). Residues of OCP's were lowest in Paettikundu and Cheravatur in all the three seasons. 相似文献
286.
Hector P. Madrid Malcolm G. Patterson Kamal S. Birdi Pedro I. Leiva Edgar E. Kausel 《组织行为杂志》2014,35(2):234-256
This article proposed and tested a multilevel and interactional model of individual innovation in which weekly moods represent a core construct between context, personality, and innovative work behavior. Adopting the circumplex model of affect, innovative work behavior is proposed as resulting from weekly positive and high‐activated mood. Furthermore, drawing on the Big Five model of personality and cognitive appraisal theory, openness to experience and support for innovation are proposed as individual and contextual variables, respectively, which interplay in this process. Openness to experience interacts with support for innovation leading to high‐activated positive mood. Furthermore, openness interacts with these feelings leading to greater levels of innovative work behavior. Overall, the model entails a moderated mediation process where weekly high‐activated positive mood represents a crucial variable for transforming contextual and individual resources into innovative outcomes. These propositions were tested and supported using a diary methodology and multilevel structural equation modeling, on the basis of 893 observations of innovative work behavior and moods nested in 10 weekly waves of data. This information was collected from 92 individuals of diverse occupations employed in 73 distinct companies. Theoretical and practical implications are discussed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
287.
针对某露天矿山实际情况,结合粉尘污染扩散理论,应用函数拟合与数值计算的方法,对该露天矿钻孔、爆破、铲装、汽车运输、倾倒作业产尘点的源强进行测定与分析,研究不同粉尘源对总产尘量的贡献率。分析得到爆破作业的产尘贡献率最大为98.145%,除爆破以外汽车扬尘为最主要设备产尘源。 相似文献
288.
通过搭建长为20m、截面为0.08m×0.08m的非绝热开口钢管,研究了甲烷与空气预混气体发生爆炸后的火焰和压力发展特征。实验结果表明:火焰信号最强的时刻对应于火焰前锋反应区内某时刻,而火焰信号起始上升时刻与火焰前锋预热区起始时刻接近,应选择某点火焰信号起始上升时刻作为该点的火焰到达时间。随着远离点火源距离的增加,火焰厚度呈现先变薄后变厚的变化趋势,最大超压呈现先减小、后增大、再减小的趋势,火焰传播速度则呈先增大后减小的变化过程。非绝热开口钢管的实验条件对爆炸超压和火焰传播速度的影响较大。研究成果可为甲烷爆炸致灾机制及防控的研究提供参考。 相似文献
289.
为了研究油气浓度对半开口管道爆炸超压特性与火焰行为的影响,建立半开口透明管道实验台架,采用5种不同初始油气浓度,进行了一系列油气爆炸对比实验。研究结果表明:油气浓度对油气爆炸超压峰值以及升压速率有显著影响,二者都呈现随浓度的增加先增大后减小的变化规律;油气浓度对火焰锋面传播速度有着显著影响,在当量浓度比下,火焰锋面的传播速度最大,并且火焰锋面的传播距离也最远;管道内的火焰行为可以分为4个阶段;油气浓度对火焰传播形态以及传播速度有明显的影响,对火焰传播形态的影响主要体现在破坏变形以及管道外爆炸阶段,随着浓度增加,爆炸半径先增大后减小,火焰传播速度呈现相同的变化规律。 相似文献
290.
Energy efficiency plays an important role in reducing the carbon externality from buildings, but economic analyses of more efficient, green building have thus far ignored input costs. This paper finds that the average marginal cost of green-labeled construction projects is smaller than the value premiums documented in the literature. However, design fees, representing just a fraction of development costs but paid largely up-front, are significantly higher for green construction projects. These projects also take longer to complete. The results provide some insight into the market barriers and market failures that may explain the relatively slow adoption of otherwise economically rational green construction practices. 相似文献