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251.
浙江省沿海地区农村房屋抗风情况调研 总被引:4,自引:0,他引:4
对浙江省沿海地区的农村房屋抗风情况进行了调研,总结了被破坏房屋的主要结构特点。在对现有房屋的统计中发现相对不富裕地区高达60%以上的房屋属于抗风能力差和较差的,而一些比较富裕且受过台风袭击有过惨痛教训地区的房屋抗风能力差和较差的仅在20%以下。进一步研究发现抗风能力较好的房屋大都是建造年代不久,多为混凝土现浇板屋盖,上部多为框架或砖混结构,而抗风能力较差和差的大都为建造年代已久,多为小青瓦屋面,上部结构多为砖木结构或构造措施较差的砖混结构。同时对当地村民传统的"砖头压瓦"防护措施进行理论验算,得出当风速超过台风界限风速时,屋面上的砖头将会飞起,该措施应该避免。 相似文献
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253.
基于矿井复杂环境对封孔水泥提出的要求,引入2-丙烯酰胺基-2-甲基丙磺酸(AMPS)并复合聚羧酸减水剂,三乙醇胺(TEA)作为有机组分,氯化钠(氯化钙)为无机组分,模拟井下高湿环境,通过正交试验,考察了两种有机无机复合早强剂的制备。并通过SEM,TG和XRD等手段着重研究了两种复合早强剂水化3d对封孔水泥抗压强度的影响。结果表明,当氯化钠复合早强剂组分为氯化钠3%,三乙醇胺0.05%,聚羧酸0.3%,AMPS1%时;氯化钙复合早强剂组分为氯化钙1.5%,三乙醇胺0.04%,聚羧酸0.2%,AMPS1%时早强效果最好,抗压强度比基准组分别提高了328%和217%。 相似文献
254.
研究了外加电压下电化学A/O-MBR的污染物去除效果和抗污染性能,分析了抗污染性能提高的原因.结果显示,外加2V电压时系统对COD和总氮的平均去除率分别为89.4%、92.2%,不加电压时COD和总氮的去除率分别为87.6%、77.3%,表明外加电压能够显著提高A/O-MBR的脱氮处理效果;研究同时发现,外加2V电压时,导电膜的平均运行周期为38d,相比不加电压时(平均26d),运行周期有所延长.污染物与导电膜之间的静电排斥作用和H2O2的原位清洗作用是系统抗污染性能提升的主要原因. 相似文献
255.
建筑企业安全文化对安全绩效影响的实证研究 总被引:1,自引:0,他引:1
王君玲 《中国安全生产科学技术》2014,(8):125-129
基于安全文化在建筑业安全管理中的重要性越来越突出,因此安全文化对于提高安全绩效,减少建筑业事故发生率的作用日益得到重视。文中进行实证研究,探讨建筑企业安全文化对安全绩效的影响。安全文化的维度为安全制度文化、安全物质文化和安全观念文化,研究结果表明,安全制度文化、安全物质文化和安全观念文化均有助于安全绩效提高,研究结果可在一定程度上促使建筑企业重视并自觉改善安全文化,有助于减少建筑业安全事故发生率,提升安全绩效。 相似文献
256.
加速溶剂萃取(ASE)-固相萃取(SPE)-高效液相色谱法(HPLC)测定土壤中青霉素钠 总被引:1,自引:0,他引:1
建立了一种加速溶剂萃取(ASE)-固相萃取(SPE)-高效液相色谱(HPLC)测定土壤中青霉素钠的简单、快速的方法.样品以超纯水为提取溶剂,50℃提取温度为ASE提取条件参数;HLB型固相萃取柱富集净化:6.0mL 5%甲醇淋洗、4.0mL乙腈-甲醇(1∶1)洗脱;高效液相色谱-紫外检测器(HPLC-PDA)测定,检测波长λ=191.1nm,柱温30℃,流动相为乙腈-0.1%甲酸/水(1∶1),采用等梯度洗脱程序,取得较好的检测分离效果.对0.5、2.0、8.0mg·kg-1等3个不同添加浓度水平的青霉素钠平均加标回收率范围为73.1%—89.7%,回收率相对标准偏差RSD范围为1.1%—2.9%(n=5),检出限可达235.0μg·L-1.结果表明,该方法操作简单,快速,准确度和精密度均符合质量控制要求,能够满足环境土壤样本中痕量青霉素钠检测分析的要求. 相似文献
257.
In studying the effect of employment‐relationship practices on employees, research has largely ignored individual differences, both cross‐culturally and within cultures. In this study, the authors examine the moderating effect of middle managers' traditionality, a within‐culture value orientation regarding submission to authority and endorsement of hierarchical role relationships, on their responses to an organization's employee–organization relationship practices. Based on social learning and social exchange theories, the authors expect the more traditional middle managers to respond less positively in terms of their performance and commitment to high levels of expected contributions and the associated psychological empowerment but respond more positively to high levels of offered inducements. Using a sample of 535 middle managers from 40 companies in China, the authors find support for all hypotheses except the moderating effect of traditionality on the relationship between offered inducements and performance. Additional analysis reveals that less‐traditional managers responded to economic rewards (but not developmental rewards) with higher job performance. The paper concludes with a discussion of implications for research and the practice of employment relationships. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
258.
Jan Alexander Häusser Stefan Schulz‐Hardt Thomas Schultze Anne Tomaschek Andreas Mojzisch 《组织行为杂志》2014,35(5):705-721
People frequently have to work in high repetitive jobs. Previous research has focused exclusively on the effects of task repetitiveness on well‐being, while neglecting effects on work performance. In the present study, we aimed to fill this void by conducting two workplace simulations with experimental manipulations of task repetitiveness. Participants worked for about 5 hours at either a computer workstation, compiling computer hardware packages according to customer requests (Experiment 1, N = 160), or at an assembly line, piecing together equipment sets for furniture (Experiment 2, N = 213). Both experiments provide consistent evidence that high repetitiveness has a detrimental effect on well‐being, whereas work performance increases under conditions of high repetitiveness. On a practical level, our study hence shows that high task repetitiveness is a double‐edged sword for both employees and organizations. On a conceptual level, our findings emphasize the necessity to account for both mental strain and work performance when examining the effects of task repetitiveness. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
259.
Jennifer A. Chatman David F. Caldwell Charles A. O'Reilly Bernadette Doerr 《组织行为杂志》2014,35(6):785-808
The relationship between organizational culture and financial performance remains elusive even though researchers have studied it for some time. Early research suggested that a strong culture that aligns members' behavior with organizational objectives boosts financial performance. A more recent view is that, because strong cultures promote adherence to routines and behavioral uniformity, they are less effective in dynamic environments. We suggest that the relationship between culture and performance can be reconciled by recognizing that culture encompasses three components: (1) the content of norms (norm content); (2) how widely members agree about norms (culture consensus); and (3) how intensely organizational members hold particular norms (norm intensity). We hypothesize that “strong cultures”—where a high consensus exists among members across a broad set of culture norms—can contribute to better financial performance even in dynamic environments if norm content intensely emphasizes adaptability. We test this hypothesis in a sample of large firms in the high‐technology industry. Firms characterized by higher culture consensus and intensity about adaptability performed better three years later than did those characterized by lower consensus, lower intensity about adaptability, or both. We discuss how parsing culture into content, consensus, and intensity advances theoretical and empirical understanding of the culture–performance relationship. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
260.
Amy L. Kristof‐Brown Jee Young Seong David S. Degeest Won‐Woo Park Doo‐Seung Hong 《组织行为杂志》2014,35(7):969-989
This study describes a multilevel examination of person–group (PG) fit perceptions in a sample of 1023 individuals working in 92 teams at a private sector R&D firm. Using confirmatory factor analysis and multilevel random coefficient modeling, we provide evidence that perceptions of team‐level collective fit are unique from aggregated individual‐level PG fit perceptions at the individual and team levels. We demonstrate that collective values‐based and abilities‐based fit perceptions showed unique and positive relationships with team cohesion, team efficacy, and team performance, after accounting for aggregated individual perceptions of PG fit. Results also demonstrate that cohesion partially mediates the relationship between collective fit and team performance. Cross‐level effects were also supported, indicating that collective fit explains additional variance in individual‐level outcomes, beyond individual‐level PG fit perceptions. The usefulness of employing a multilevel approach to studying PG fit is discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献