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71.
张桂华 《湖南环境生物职业技术学院学报》2006,12(3):328-331
围绕文化差异与跨文化营销的主要研究成果,分析文化差异与跨文化营销研究的兴起情况以及国内外学者对文化差异和跨文化营销的研究的现状. 相似文献
72.
In recent decades numerous diversity indices have been introduced. Among them the quadratic entropy index Q expresses the mean difference between two individuals chosen from the community at random. Differing from diversity indices habitually employed, Q does not satisfy a property postulated earlier for those measures. Namely, the uniform distribution of species does not necessarily yield the maximal index value. Q is based on the difference matrix of species. For a given matrix one can seek for the vector yielding the maximum quadratic entropy. This task leads to a quadratic programming problem. Using the appropriate program of a program package, we determined the maximum vector for a genetic difference matrix of crane species, as published in the literature. We discovered that some components (frequencies) in the maximum vector are equal to zero. That is, by maximizing the quadratic diversity some species can be eliminated. We discuss briefly the possible implications of this observation. Moreover, even if all elements in the maximum vector are positive, the elements can differ. 相似文献
73.
Size assessment via a visual signal in snapping shrimp 总被引:2,自引:0,他引:2
Melissa Hughes 《Behavioral ecology and sociobiology》1996,38(1):51-57
Snapping shrimp are highly aggressive decapod crustaceans, with large, asymmetric chelae. Body size determines the outcome
of both inter- and intrasexual interactions. Both the body and chela sizes of mated pairs are correlated, but the body size
correlation is significantly stronger. In competitive interactions between individuals of the same sex, larger individuals
usually win. Because the size of the major chela is a function of body size in both males and females, chela size could be
used to assess body size early in interactions, before engaging in more high risk behaviors. To determine whether the major
chela is used in size assessment, I presented shrimp with isolated chelae. Male snapping shrimp responded aggressively to
isolated chelae when they were fixed open in a display posture, and the degree of aggressive response depended on the relative
size of the chela. These data provide direct experimental evidence for the use of a visual signal in size assessment. Females,
in contrast, responded aggressively to both the open and closed chela, and their responses did not depend on relative size.
This sex difference in response may be due to differences in the value of certain resources, such as shelters, to males and
females: females may be more willing to respond aggressively regardless of the apparent size of their opponent, in order to
acquire more reliable information regarding size, motivation or fighting ability.
Received: 30 December 1994/Accepted after revision: 14 August 1995 相似文献
74.
为揭示碳氮比(C/N)对硝化过程影响的机理本质,试验以人工模拟废水为研究对象,采用4组平行的SBR(R0、R5、R10、R15)反应器,基于16S rRNA基因-Illumina MiSeq高通量测序技术,考察了4种C/N(0、5、10、15)对硝化过程功能微生物组成和结构特征的影响.结果表明:4种C/N条件下,系统均获得了较好的去除氨氮(去除率>95%)和COD(去除率>90%)效果,TN也有不同程度的降低.此外,C/N会显著影响系统内微生物的多样性、种群结构和功能.R0系统Chao1指数(922)、ACE指数(1232.4)、Shannon指数(6.76)和Simpson指数(0.96)均最大,故微生物多样性最丰富,而R5的物种丰富度最低.在微生物门水平上,变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、蓝细菌门(Cyanobacteria)等9个相对丰度较高的门是重要的微生物门,其中变形菌门(Proteobacteria)约全部微生物的40.7%~65.2%,是4个系统中最优势的菌门.硝化过程的关键菌群亚硝化单胞菌科(Nitrosomonadaceae)及硝化螺旋菌属(Nitrospira)的相对丰度表现出随着C/N升高而急剧降低的趋势.基于LEfSe分析共获得了34组具有显著差异的微生物,从而得到了每种C/N条件下在微生物学分类水平上的菌群关键生物标记物. 相似文献
75.
为了解河北省涞水县颗粒物污染特征,采用单颗粒分析技术扫描电镜-X射线能谱法和气团后向轨迹分析技术对该县2015年3个典型污染时段〔即正常管控、严格管控(2015年阅兵期间)及发生严重颗粒物染污〕采集的7个大气颗粒物样品进行了分析表征和来源解析.共测量了1 506个粒径≥0.5 μm的单颗粒,其中粒径小于2.5 μm的颗粒占98%以上,测量结果揭示了细颗粒污染特征.结果表明:①碳质颗粒为主要颗粒物种类,其检出数目占比在90%以上.②非供暖期严格管控时段,当地居民日常生活产生的球形碳质颗粒检出数目占比最高.③非供暖期正常管控时段,机动车排放的碳质集合体颗粒检出数目占比最高,交通污染贡献最大.④供暖期球形碳质颗粒检出数目占比最高,含硫颗粒检出数目占比相对增加,燃煤的贡献最大.3个采样时段48 h气团后向轨迹分析结果表明,在空气质量良好、颗粒物污染水平较低的情况下,影响研究区域空气质量的主要是本地源;雾霾天气(处于严重颗粒物污染时段)时,西南方向外来源和本地源共同构成研究区域的颗粒物污染状态. 相似文献
76.
为了评价油品储运过程中的流淌火灾风险,提出1种基于FERC模型的油品流淌火灾定量风险评估方法。以某汽油管道为例,分析大孔泄漏、中孔泄漏、小孔泄漏3种模式下流淌火各参数的动态变化过程,计算管道周边不同位置处的个人风险值。研究结果表明:流淌火燃烧面积的最大值随泄漏速率的增加而增大,对于给定的算例条件,大孔泄漏情景下的最大燃烧半径较小孔泄漏增大了18.4倍;相较小孔泄漏,大孔泄漏下安全距离增大了6.7倍;在距离泄漏点100 m的位置,小孔泄漏、中孔泄漏和大孔泄漏条件下的辐射热流密度值分别为0.13,1.34,8.02 kW/m2;距离泄漏点34 m处时,大孔泄漏已经占总个人风险的99%;在开展风险评价时,应着重分析大孔泄漏的情景。 相似文献
77.
A multilevel study of group‐focused and individual‐focused transformational leadership,social exchange relationships,and performance in teams
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Using matched reports from 73 team leaders and 359 of their members across 23 companies in Korea, we examined a multilevel model where group‐ and individual‐focused transformational leadership and their influence processes operate at the team and dyadic levels independently and interactively to be associated with team and member performance. Results indicated that group‐focused transformational leadership was positively associated with team performance through team member exchange (TMX), whereas individual‐focused transformational leadership positively related to team members' in‐role and extra‐role performance through leader–member exchange (LMX). TMX not only positively mediated the relationships between group‐focused transformational leadership and member performance after controlling for LMX but also positively moderated LMX–performance relationships. Moreover, the indirect effect of individual‐focused transformational leadership through LMX on member performance was contingent upon the level of TMX. Theoretical and applied implications are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
78.
在前人研究成果的基础上,选择认知水平、同事顾虑、上级领导抵触、利己考虑、集体考虑、系统本身、安全文化7个影响因素,并依据SCASS分类标准,将上报意愿分为6个维度(报告提交经验、航空器不良运行或设备缺陷报告提交意愿、自身违规差错报告提交意愿、空防安全事件或隐患报告提交意愿、执行标准或飞行程序困难事件报告提交意愿、同事发生此类事件报告提交意愿),构建并验证个体自愿上报意愿的影响因素模型。研究发现,各类事件上报意愿分别受到不同的因素影响,其中,认知水平和安全文化对上报意愿起到正向影响,其他影响因素起到负向影响。本研究为民航单位针对性提高员工上报意愿提供理论指导。 相似文献
79.
A multilevel perspective of interpersonal trust: Individual,dyadic, and cross‐level predictors of performance
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While it is generally known that interpersonal trust facilitates individual functioning, few studies have examined the role of specific features of the interpersonal trust network — individual, dyadic, third‐party, and network‐level features — on individual performance. We adopt a multilevel perspective of interpersonal trust to examine how individuals' performance is not only predicted by their individual‐level centrality in the interpersonal trust network but also moderated, at the network level, by the overall centralized nature of that network. Further, we examine whether mutual trust relationships at the dyadic level, as well as shared trust ties to common third parties, can predict individuals' performance. We test our hypotheses with 206 members in 15 professional networking groups and find that interpersonal trust operates at multiple levels to predict members' performance in terms of generating income from business referrals. These findings provide theoretical and practical implications on how interpersonal trust relationships operate and can be managed for performance gains. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
80.
Leaders face a challenge to simultaneously motivate workgroups and the individuals within them. Recent criticisms highlight the need to deconstruct broad leadership constructs to offer better theoretical insight into the effects of specific leadership behaviors on groups versus individuals. We address this call by exploring the effects of group‐focused and individual‐focused aspects of transformational leadership. Applying social identity theory, we theorize that group‐focused transformational leadership is key to fostering felt obligation, motivating helping behavior, and enhancing group performance, whereas individual‐focused leadership may only foster helping when individuals also feel a sense of obligation toward their workgroup. In a field study of 260 employees reporting to 36 supervisors in a skilled trade company, we find support for these predictions using multilevel structural equation modeling and multilevel mixed effects modeling. Thus, group‐focused (vs. individual‐focused) transformational leadership and subsequent felt obligation are important antecedents for encouraging helping and, in turn, workgroup performance. 相似文献