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501.
The decision gym: decision insurance for organizations 总被引:1,自引:1,他引:0
Conducting decision calisthenics can help an organization win competitive advantage through harnessing its tremendous knowledge, imagination, and staff experience. The paper explores how knowledge and experience mined and refined through innovative approaches like scenarios and war gaming can turn visionary ideas into successful, working realities. To fully appreciate the value of novel frameworks requires contextualizing their utility in what can be called the decision gym. The decision gym offers a way to build powerful consensus and commitment to decisions, methods to optimize processes, and a way to create, evaluate, and execute critical strategies in the face of heuristics and biases that can distort decision making. 相似文献
502.
503.
Epidemiological studies have shown that particulate matter 2.5 (PM2.5) not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering that PM2.5 is highly heterogeneous with regional disparity and seasonal variation, we investigated whether PM2.5 exposure induced neuronal apoptosis and synaptic injuries in a season-dependent manner. The results indicated that PM2.5 altered the expression of apoptosis-related proteins (mainly bax and bcl-2), activated caspase-3 and caused neuronal apoptosis. Additionally, PM2.5 decreased the levels of synaptic structural protein postsynaptic density (PSD-95) and synaptic functional protein N-methyl-D-aspartate (NMDA) receptor subunit (NR2B) expression. These effects occurred in a season-dependent manner, and PM2.5 collected from the winter showed the strongest changes. Furthermore, the effect was coupled with the inhibition of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and phosphorylated cAMP-response element binding protein (p-CREB). Based on the findings, we analyzed the correlations between the chemical composition of PM2.5 samples and the biological effects, and confirmed that winter PM2.5 played a major role in causing neuronal apoptosis and synaptic injuries among different season samples. 相似文献
504.
An insight into the removal of fluoroquinolones in activated sludge process: Sorption and biodegradation characteristics 总被引:2,自引:0,他引:2
The detailed sorption steps and biodegradation characteristics of fluoroquinolones(FQs)including ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and ofloxacin were investigated through batch experiments. The results indicate that FQs at a total concentration of 500 μg/L caused little inhibition of sludge bioactivity. Sorption was the primary removal pathway of FQs in the activated sludge process, followed by biodegradation, while hydrolysis and volatilization were negligible. FQ sorption on activated sludge was a reversible process governed by surface reaction. Henry and Freundlich models could describe the FQ sorption isotherms well in the concentration range of 100–300 μg/L. Thermodynamic parameters revealed that FQ sorption on activated sludge is spontaneous, exothermic, and enthalpy-driven. Hydrophobicity-independent mechanisms determined the FQ sorption affinity with activated sludge. The zwitterion of FQs had the strongest sorption affinity, followed by cation and anion, and aerobic condition facilitated FQ sorption. FQs were slowly biodegradable, with long half-lives( 100 hr). FQ biodegradation was enhanced with increasing temperature and under aerobic condition,and thus was possibly achieved through co-metabolism during nitrification. This study provides an insight into the removal kinetics and mechanism of FQs in the activated sludge process, but also helps assess the environmental risks of FQs resulting from sludge disposal. 相似文献
505.
Sulfur dioxide(SO_2) pollution in the atmospheric environment causes brain inflammatory insult and inflammatory-related microvasculature dysfunction.However,there are currently no effective medications targeting the harmful outcomes from chemical inhalation.Endocannabinoids(eCBs) are involved in neuronal protection against inflammation-induced neuronal injury.The 2-arachidonoylglycerol(2-AG),the most abundant eCBs and a full agonist for cannabinoid receptors(CB1 and CB2),is also capable of suppressing proinflammatory stimuli and improving microvasculature dysfunction.Here,we indicated that endogenous 2-AG protected against neuroinflammation in response to SO_2 inhalation by inhibiting the activation of microglia and astrocytes and attenuating the overexpression of inflammatory cytokines,including tumor necrosis factor alpha(TNF-a),interleukin(IL)-1β,and inducible nitric oxide synthase(iNOS).In addition,endogenous 2-AG prevented cerebral vasculature dysfunction following SO_2 inhalation by inhibiting endothelin 1(ET-1),vascular cell adhesion molecule-1(VCAM-1) and intercellular adhesion molecule 1(ICAM-1) expression,elevating endothelial nitric oxide synthase(eNOS) level,and restoring the imbalance between thromboxane A2(TXA2) and prostaglandin 12(PGI2).In addition,the action of endogenous 2-AG on the suppression of inflammatory insult and inflammatory-related microvasculature dysfunction appeared to be mainly mediated by CB1 and CB2 receptors.Our results provided a mechanistic basis for the development of new therapeutic approaches for protecting brain injuries from SO_2 inhalation. 相似文献
506.
Composting of spent pig litter at different seasonal temperatures in subtropical climate 总被引:1,自引:0,他引:1
To investigate the effects of seasonal temperatures on the composting of spent pig-manure sawdust litter (spent litter), two sets of experiments were carried out: one during winter, the other during summer. Physicochemical and microbial parameters including temperature, pH, inorganic N, humification indicators (HA and FA), heavy metals (Cu and Zn), total aerobic heterotrophs, ATP content and dehydrogenase activity were measured to understand changes in the spent litter during composting. Results demonstrated that the composting was faster during summer than winter. The spent litter during the summer trial reached maturity at day 56 whereas that of the winter trial was still immature at the end of composting (days 91). Microbial activities during the thermophilic stage of composting were much lower in the winter trial. Values began to increase during the latter part of composting, indicating that the spent litter in this winter trial was biologically unstable and must be further composted to reach full maturity. The changes in the microbial activities of the spent litter during summer or winter reflected the changes in their temperatures and chemical properties. The maturation of the spent litter during summer was accompanied by stabilization of the microbial and chemical properties and a drop in temperature to ambient level. Results of correlation analysis showed that temperature correlated not only with the microbial parameters but also with most of the chemical parameters. These parameters also correlated with each other. Among all the parameters measured, the trend of temperature changes is the simplest and most rapid parameter that can be used to evaluate the maturity of spent litter. 相似文献
507.
气提式循环反应器处理污水试验研究 总被引:5,自引:0,他引:5
主要探讨了气提式循环反应器处理污水的几个有关问题 :载体选择 ,提升区的截面大小选择 ,载体生物膜和游离活性污泥的特点。试验结果表明 :载体材料中 ,焦炭稍优于炉渣 ,塑料效果最差 ;提升区应该存在最优截面尺寸 ,使载体的提升循环量最高 ;载体生物膜的存在 ,增加了生物量 ,提高了处理效率 ,而且是促进硝化作用的主要因素 相似文献
508.
Beth E. Waller Casey W. Hoy Janet L. Henderson Ben Stinner Celeste Welty 《Agriculture, ecosystems & environment》1998,70(2-3)
Through interviews and mail surveys, Ohio potato (Solanum tuberosum) growers were surveyed concerning their willingness to adopt three cultural controls being developed for management of the Colorado potato beetle, Leptinotarsa decemlineata (Say), which had become increasingly difficult to control. The principal objective of the research was to obtain a deeper understanding of how farmers make decisions to adopt or not adopt new techniques and how these decisions are related to farmers' educational backgrounds and the way they currently manage their farms. The three cultural management options emphasized ecological approaches to habitat management rather than ecologically disruptive chemical control: (1) using host plants in overwintering sites to slow the spring movement of the beetles to potato fields, (2) using larger potato plants at field borders than in the center of the field as a spring trap crop, and (3) concentrating beetles in relatively small undefoliated areas to be killed with heat in late summer. Most respondents would not adopt these alternative pest management strategies, mainly because they perceived an unsatisfactory trade-off between logistic difficulties and expenses and population suppression they would achieve compared with traditional chemical control measures. Education correlated positively and experience in farming negatively with the willingness to try new pest management techniques. Additionally, growers responding more negatively to questions regarding integrated pest management strategies were more willing to experiment with the alternative techniques, a result attributed to either the survey design or an indication of experience with the more intensive management effort required for integrated pest management. This profile of potential innovators should be used by researchers to establish partnerships with farmers that could assist with both the research and development of new farming techniques and the adoption of successful systems by other farmers. 相似文献
509.
The brown shrimp, Penaeus aztecus, in the northern Gulf of Mexico is faced with dual stresses of environmental hypoxia, which occurs as a result of oxygen depletion from microbial decomposition of organic materials from algal blooms, and pollution from polycyclic aromatic hydrocarbons (PAHs) from petroleum and gas production on the continental shelf of the northern Gulf of Mexico. This study investigated the effect of naphthalene, a PAH, on oxyregulating capacity of P. aztecus, when shrimps were subjected to progressive hypoxia. It was found that P. aztecus is an oxyregulator with a critical oxygen concentration of 2.53 mg/l at 19–21°C, below which the animal becomes an oxyconformer. Acute exposure to naphthalene at 2.0 mg/l significantly reduced the oxyregulating capacity by 112%. This is the first report on the alteration of an aquatic animal’s oxyregulating capacity by a PAH. Possible mechanism for the impaired oxyregulation in the presence of naphthalene was discussed. 相似文献
510.