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排序方式: 共有1441条查询结果,搜索用时 281 毫秒
881.
882.
Angsumita Pramanick Abhiram Kanneganti Jing Lin Jeslyn Wong Sarah Weiling Li Pooja Sharma Dimri Aniza Puteri Mahyuddin Sailesh Kumar Sebastian Enrique Illanes Jerry Kok Yen Chan Lin Lin Su Arijit Biswas Paul Anantharajah Tambyah Ruby Yun-Ju Huang Citra Nurfarah Zaini Mattar Mahesh Choolani 《黑龙江环境通报》2021,41(8):1018-1035
There are over 50 SARS-CoV-2 candidate vaccines undergoing Phase II and III clinical trials. Several vaccines have been approved by regulatory authorities and rolled out for use in different countries. Due to concerns of potential teratogenicity or adverse effect on maternal physiology, pregnancy has been a specific exclusion criterion for most vaccine trials with only two trials not excluding pregnant women. Thus, other than limited animal studies, gradually emerging development and reproductive toxicity data, and observational data from vaccine registries, there is a paucity of reliable information to guide recommendations for the safe vaccination of pregnant women. Pregnancy is a risk factor for severe COVID-19, especially in women with comorbidities, resulting in increased rates of preterm birth and maternal morbidity. We discuss the major SARS-CoV-2 vaccines, their mechanisms of action, efficacy, safety profile and possible benefits to the maternal-fetal dyad to create a rational approach towards maternal vaccination while anticipating and mitigating vaccine-related complications. Pregnant women with high exposure risks or co-morbidities predisposing to severe COVID-19 infection should be prioritised for vaccination. Those with risk factors for adverse effects should be counselled accordingly. It is essential to support patient autonomy by shared decision-making involving a risk-benefit discussion with the pregnant woman. 相似文献
883.
Coordination Degree of Urban Population, Economy, Space, and Environment in Shenyang Since 1990 总被引:1,自引:0,他引:1
In the background of China's rapid urbanization, the conflicts between urban population, economy, space, and environment are intensified and complicated. This article aims to establish a coordinate assessment method for studying urban population, economy, space, and environment interactions in city scale by principal component analysis and regression analysis. On the basis of the case study on Shenyang city, the results indicated that the integrated development of urban population, economic, and space was in a poor situation from 1993 to 1999, whereas it turned better after 2000, and the urban environment improved steadily after 1998. The static coordination degree of urban integrated development and environment showed obvious periodical and fluctuant characteristics. Compared with the static coordination degree, the dynamic coordination degree appeared to be smooth and lag. The static coordination degree was elementary discoordinative in 1993, 1994, and 1999; whereas it turned to be elementary coordinative between 1995 and 2005. The dynamic coordination degree was elementary discoordinative from 1993 to 1996, whereas it became elementary coordinative overall after 1997. 相似文献
884.
安徽沿江地带投资环境综合研究 总被引:1,自引:0,他引:1
苏勤 《长江流域资源与环境》1997,6(4):302-307
改善投资环境吸引外资是经济发展的重要内容。安徽沿江地带是长江经济带重要的组成部分,对安徽沿江地带投资环境进行了分析与评价,并就进一步完善沿江地带宏观投资环境,推动经济联合发展提出了建议与措施。 相似文献
885.
乌鲁木齐市医院污水处理水平现状分析 总被引:4,自引:0,他引:4
乌鲁木齐地区共有29家大中型医院,建立污水处理设施的共有15家,占51.7%,其中处理后达标排放的占31.6%。从处理方法及效果来看,经一级处理的医院排水,主要监测指标仍有不同程度的超标,采用二级处理的效果则比较显著。为确保2000年达标排放,有关部门应采用相应的措施督促大中型医院尽早用二级处理方法处理其排水。 相似文献
886.
Aviation’s highest priority is safety. The primary risk to safety derives not from automated systems but from human factors, most notably air traffic control. We present results from development of a flight case learning system designed to operate on mobile phones used by air traffic controllers (ATCs). Our system takes advantage of key Ontology concepts, a case-based system development procedure, human-centered design (HCD) strategies, and appropriate small-screen interface design protocols. A questionnaire to assess user interaction satisfaction (QUIS) was deployed for subsequent usability testing and to verify acceptance of, and satisfaction with, the system. Twelve subjects participated in the questionnaire-based evaluation of subjective satisfaction. In addition, two flight experts served on a review panel for domain knowledge verification and acceptance of the interface design. Our results confirm that the system is a suitably designed mobile learning system that can accelerate self-learning for ATCs. 相似文献
887.
Yu-Jen Shih Hsiao-Ting Su Yao-Hui Huang 《Environmental science and pollution research international》2013,20(9):6184-6190
The degradation of phenol in acidic solution at pH 3 has been investigated under various photo- and electrochemical conditions. A laboratory-scale reactor on which were mounted net electrodes (RuO2/IrO2-coated Ti anodes (DSA) and stainless steel cathodes) and 254 nm UV lamps was established to effectively reduce ferric reagents. The experimental results of the photoelectron-chemical reaction suggested that the current efficiency of reducing ferric ion was improved by increasing the number of electrodes used, and the UV lamps were important to inducing the reduction of ferric carboxylates, which were the major intermediates that were formed upon a particular degree of phenol oxidation. Accordingly, the addition of an initial concentration of 400 ppm ferrous salt and 10,200 ppm hydrogen peroxide (in a continuous mode) resulted in the removal of over 92 % of TOC (initial phenol?=?2,000 ppm, TOC?=?1,532 ppm) by 4 h of the photoelectro-Fenton and the sequential 2 h of the photo-Fenton processes. HPLC was utilized to monitor the formation of aromatic and carboxylate byproducts, and revealed that the aid of photo irradiation eliminated most of the oxalate residue from the final solution, which would have contributed to the 25 % of the TOC that was inactive in the electrolytic system. 相似文献
888.
In 2005 a pollution accident occurred in the Songhua River, which is geographically located next to groundwater supply plants. This caused public concern about the transport and fate of nitrobenzene (NB) in the groundwater. This paper discusses the mechanisms and effects of the transport and fate of NB in groundwater based on pilot scale experiments conducted in the laboratory, including a simulation experiment, bench-scale batch tests and a one-dimensional numerical model. Parallel batch tests showed that the adsorption of NB to the clay and sand followed the Langmuir-type isotherm, and clay had a greater NB adsorption capacity than sand. NB biodegradation in different conditions was well fitted by the Monod equation and the qmax values varied from 0.018 to 0.046 h?1. Results indicated that NB’s biodegradation was not affected by the initial NB concentration. Numerical modeling results indicated a good match between computed and observed data, and in the prediction model NB entered the groundwater after the pollution accident. However, the highest concentration of NB was much lower than the allowable limit set by the national standard (0.017 mg/L). 相似文献
889.
黄山贫困山区资源特点与治贫开发对策 总被引:1,自引:0,他引:1
苏勤 《长江流域资源与环境》1996,(4)
黄山是我国十大风景名胜区之一,但全区经济发展水平十分落后,属安徽省贫困地区之一。本文对黄山贫困山区的资源特点与存在问题进行了综合分析,指出了本区贫困落后的主要原因,并就治贫开发提出了相应对策。 相似文献
890.
Aniza P. Mahyuddin Abhiram Kanneganti Jeslyn J.L. Wong Pooja S. Dimri Lin L. Su Arijit Biswas Sebastian E. Illanes Citra N. Z. Mattar Ruby Y.-J. Huang Mahesh Choolani 《黑龙江环境通报》2020,40(13):1655-1670
There remain unanswered questions concerning mother-to-child-transmission of SARS-CoV-2. Despite reports of neonatal COVID-19, SARS-CoV-2 has not been consistently isolated in perinatal samples, thus definitive proof of transplacental infection is still lacking. To address these questions, we assessed investigative tools used to confirm maternal-fetal infection and known protective mechanisms of the placental barrier that prevent transplacental pathogen migration. Forty studies of COVID-19 pregnancies reviewed suggest a lack of consensus on diagnostic strategy for congenital infection. Although real-time polymerase chain reaction of neonatal swabs was universally performed, a wide range of clinical samples was screened including vaginal secretions (22.5%), amniotic fluid (35%), breast milk (22.5%) and umbilical cord blood. Neonatal COVID-19 was reported in eight studies, two of which were based on the detection of SARS-CoV-2 IgM in neonatal blood. Histological examination demonstrated sparse viral particles, vascular malperfusion and inflammation in the placenta from pregnant women with COVID-19. The paucity of placental co-expression of ACE-2 and TMPRSS2, two receptors involved in cytoplasmic entry of SARS-CoV-2, may explain its relative insensitivity to transplacental infection. Viral interactions may utilise membrane receptors other than ACE-2 thus, tissue susceptibility may be broader than currently known. Further spatial-temporal studies are needed to determine the true potential for transplacental migration. 相似文献