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81.
Recent crises in regions where exclusive breastfeeding is not the norm have highlighted the importance of effective policies and guidelines on infant feeding in emergencies. In 1993, UNICEF compiled a collection of policy and guideline documents relating to the feeding of infants in emergency situations. In June 2000 Save the Children, UK, UNICEF and the Institute of Child Health undertook a review of those documents, updating the list and identifying the common ground that exists among the different policies. The review also analysed the consistency of the policy framework, and highlighted important areas where guidelines are missing or unclear. This article is an attempt to share more widely the main issues arising from this review. The key conclusions were that, in general, there is consensus on what constitutes best practice in infant feeding, however, the lack of clarity in the respective responsibilities of key UN agencies (in particular UNICEF, UNHCR and WFP) over issues relating to co-ordination of activities which affect infant-feeding interventions constrains the implementation of systems to support best practice. Furthermore, the weak evidence base on effective and appropriate intervention strategies for supporting optimal infant feeding in emergencies means that there is poor understanding of the practical tasks needed to support mothers and minimise infant morbidity and mortality. We, therefore, have two key recommendations: first that the operational UN agencies, primarily UNICEF, examine the options for improving co-ordination on a range of activities to uphold best practice of infant feeding in emergencies; second, that urgent attention be given to developing and supporting operational research on the promotion of optimal infant-feeding interventions. 相似文献
82.
采用淡水沉积物质量基准和微生物毒性试验方法,对疏浚前后五里湖沉积物提取液和全底泥沉积物的生态毒性进行了研究与分析.结果表明,疏浚后,沉积物中各重金属污染物的总体含量均显著降低,但是铬、铅和镍的含量仍然分布在阈值效应低值(TEL)和可能效应水平值(PEL)之间的灰色区域,仍可能对水体生态系统产生不良影响;疏浚后1个月,沉积物提取液中发光菌发光试验的EC50值降低约50%,毒性增加近1倍;与疏浚前相比,全底泥沉积物的细菌毒性试验的EC50值降低11%~30%;全底泥月芽藻毒性试验的EC50值也有显著降低. 相似文献
83.
Governments and industries have introduced regulatory measures requiring safety controls to limit asbestos exposure of the general public and asbestos workers. Although erionite is a more potent health hazard mineral than asbestos, it has received far less attention. Precise definition of erionite, types of these fibrous minerals, and most importantly, characterization requirements still raise questions and often lead to arguments and even legal disputes. Many bulk erionite samples used in animal and cell experiments for carcinogenicity are not mineralogically pure. To test this hypothesis, we characterized two erionite standards from Rome, Oregon, and Pine Valley, Nevada, USA. These standards were characterized quantitatively using modern analytical techniques, and one of them, the erionite standard from Rome, Oregon, passed the required tests for positive identification, but the other, the erionite standard from Pine Valley, Nevada, did not. Furthermore, we observed ambiguous definitions, incorrect identifications, and inaccurate reporting of clinical investigations. To address this problem, we established characterization guidelines for positive identification of erionite using a modified balance error formula, and we re-evaluated and re-classified published erionite data from the literature as erionite-Ca, erionite-Na, and erionite-K. If data did not pass either the E% or Mg-content test, then we propose that reference to them in the literature be disregarded. Erionite requires special attention from the mineralogical community to help establish its true carcinogenetic properties. We believe that the characterization guidelines established in this paper will contribute to setting up rules and regulations for evaluation of erionite by regulatory agencies. 相似文献
84.
目的 解决现有接口电路俘能效率低、开关控制电路模块结构复杂等问题。方法 基于电压翻转及电荷提取技术,提出一种自供电式同步翻转电荷提取的压电能量俘获电路(Self-Powered Optimized Synchronous Inversion and Charge Extraction Circuit,SP-OSICE)。该电路设计了2个电压峰值检测电路,检测压电换能器两端电压峰值,并在正峰值处进行一次电压翻转,然后在负峰值处采用同步电荷提取方法,提取压电换能器寄生电容上储存的电荷,提高能量的收集效率。结果 在低负载区,SP-OSICE电路的输出功率略低于SICE电路的输出功率,随着负载电压的增大,SP-OSICE电路的输出功率略高于SICE电路,且可达到全桥整流电路最大输出功率的6倍以上。结论 SP-OSICE电路优化了SICE电路中的开关控制策略,无需整流桥结构,提高了接口电路的输出功率。整体电路采用自供电设计,无需外部辅助电路控制晶体管通断,降低了电路结构的复杂性。仿真和实验结果均验证了SP-OSICE电路的优势。 相似文献
85.
The promotion of development projects based on the commercialization of non‐timber forest products has increased in recent decades, showing a positive contribution to rural development; yet it has led to controversial approaches in resource preservation. This paper examines the case of Candelilla wax from the Chihuahuan Desert in northern Mexico, identifying its potential contribution to poverty alleviation in marginal areas, and its unique opportunity to access potential markets of a wide variety of industries all around the world. In this paper, the authors base their analysis on three main aspects: social, economic and environmental. Potential benefits that could be obtained from the collaboration of private institutions, development organizations, policymakers and rural producers through integrated rural development projects are featured. 相似文献
86.
长江口沉积物重金属赋存形态及风险特征 总被引:7,自引:1,他引:6
基于长江口沉积物8种重金属(As、Cd、Cr、Cu、Hg、Ni、Pb、Zn)总量与形态在丰、平、枯水期以及14个典型点位的分布特征,通过平衡分配法建立了长江口沉积物质量基准(SQGs),并以此评价长江口沉积物重金属生态风险,揭示重金属生态风险与其形态特征间的相关关系.结果表明,除Cd之外,长江口沉积物重金属以残渣态为主导形态,尤其是As、Cr、Hg,其残渣态含量均为90%以上.长江口As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的沉积物质量基准分别为43.29、0.672、79.65、19.08、0.569、339.09、30.87、411.36μg·g~(-1).Cu的生态风险程度最高,对水生生物具有较大的毒性影响,应当引起重视.河口上游受到长江径流影响大,在丰水期风险较高,在平水期和枯水期则风险偏低;而下游受上海等城市排污影响较大,风险较高(尤其在平水期和枯水期).8种重金属的生态风险与赋存形态之间表现出3种不同的相关关系. 相似文献
87.
88.
在中国农村劳动力非农就业不断加速的背景下,探讨非农就业对集体林区不同规模林农营林轮伐期的影响机制,有助于明确不同规模经营主体今后的用材林营林目标和林业在山区未来的经营发展模式,同时为林业规模化经营的合理性提供客观依据。基于劳动力转移新经济学理论,通过对浙江、江西和福建三省450户林农的调查,收集杉木营林的地块投入产出数据,在此基础上,运用Faustmann模型计算规模户与普通户的理论最优轮伐期,运用计量模型分析非农就业对集体林区不同规模林农采伐轮伐期的影响机制。研究结果发现,普通户和规模户的理论最优轮伐期趋同;非农就业的劳动力流失效应造成普通户营林的预期主伐时间显著短于理论最优轮伐期,而规模户非农就业带来的收入效应造成其采伐决策接近于理论最优轮伐期。在农村非农就业不断增加背景下,南方集体林区规模化经营的方式有利于接近最优采伐决策,更适合于培育大径材,增加林业生态和经济效益。 相似文献
89.
Edwards NC 《Journal of Safety Research》2011,42(6):537-541
There is a growing body of research about the etiology and prevention of falls. However, the persistently high incidence of falls among seniors calls for renewed efforts to develop, test, implement, and scale-up fall prevention strategies for older adults. This paper considers advances in the field and describes three priority areas for generating research and translating knowledge on fall prevention. Clinical practice guidelines, systems change approaches and environmental risk factors are discussed. Recommendations include transcending our health sector view of the fall prevention problem, supporting comparative research on system-oriented approaches to fall prevention, and examining ways to sustain and scale-up fall prevention efforts. 相似文献
90.
Progress in formulating and implementing effective adaptation policies is often hampered by a wide variety of barriers that are well documented in the literature. Among the barriers are lack of awareness, certainty, resources and political commitment. Since these and other barriers can be overcome (e.g., by raising awareness, closing knowledge gaps, and increasing resources), numerous decision‐support frameworks (mainly written guidelines) have been developed for this purpose. The present paper takes stock of both the barriers in adaptation policymaking, as documented in the literature, and the guidelines that aim to facilitate public policies on climate change adaptation. It then compares to what degree selected adaptation guidelines serve as knowledge‐brokerage tools that provide guidance on how to overcome the barriers addressed in the scientific literature. The comparison shows that adaptation guidelines address barriers of adaptation policymaking neither comprehensively nor systematically. Since most adaptation guidelines focus on (subjective) experiences with good practices than on empirical research findings, we conclude that they represent a missed opportunity of scientific knowledge‐brokerage in climate change adaptation. 相似文献