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171.
Survival of children with congenital diaphragmatic hernia (CDH) is mainly dependent on the extent of lung hypoplasia and the presence of additional congenital anomalies or chromosomal aberrations. A chromosomal deletion 15q25-q26.2 in a fetus with prenatally diagnosed CDH and growth retardation is reported. Despite optimal pre- and neonatal management the baby died shortly after birth. There is increasing evidence that the long arm of chromosome 15, and especially the region 15q24 to 15q26, plays a crucial role in the development of the diaphragm. The finding of a deletion within 15q24-26 in a fetus with CDH has to be considered a predictor of poor prognosis. It is of utmost interest for proper parental counselling to search in fetuses with CDH for subtle chromosomal lesions paying special attention to chromosome 15q. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
172.
Kevin Spencer Adolfo W. Liao Charas Y. T. Ong Lut Geerts Kypros H. Nicolaides 《黑龙江环境通报》2001,21(9):718-722
Placenta growth factor (PIGF), an angiogenic factor belonging to the vascular endothelial growth factor family, pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotrophin (β-hCG) were measured in maternal serum from 45 pregnancies with trisomy 21, 45 with trisomy 18 and 493 normal controls at 10–13 completed weeks of gestation. In the normal pregnancies maternal serum PIGF levels increased exponentially with gestation. The median multiple of the median (MoM) PIGF concentration in the trisomy 21 group (1.26 MoM) was significantly higher (p<0.0001) than in the control group (1.00 MoM). In the trisomy 18 group the median PIGF was lower (0.889 MoM) but this did not quite reach significance (p=0.064). The corresponding median MoM values for PAPP-A were 1.00 MoM for the controls, 0.49 MoM for trisomy 21 and 0.16 MoM for trisomy 18. The median MoM values for free β-hCG were 1.00 MoM for the controls, 2.05 MoM for trisomy 21 and 0.38 MoM for trisomy 18. In the control group there was a small but significant correlation of PIGF with free β-hCG (r=+0.1024) and PAPP-A (r=+0.2288). In the trisomy 18 group there was a significant association between PIGF and free β-hCG (r=+0.2629) but not with PAPP-A (r=+0.0038). In the trisomy 21 group there was a small but significant association with PAPP-A (r=+0.1028) but not with free β-hCG (r=+0.0339). The separation of affected and unaffected pregnancies in maternal serum PIGF is small, and therefore it is unlikely that measurement of PIGF would improve screening for these abnormalities provided by the combination of fetal nuchal translucency and maternal serum PAPP-A and free β-hCG. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
173.
科技资源开发与区域经济增长研究--以河南为例 总被引:5,自引:0,他引:5
本文以河南为例,对科技资源的存量动态变化、配置效率及其对区域经济增长的推动作用进行了定量分析。结果表明。1991.2002年。河南科技资源存在总体上呈持续上升趋势。但是。科技资源的配置效率却呈现出下降趋势。在这个期间。科技资源开发对河南区域经济增长的贡献率为42.1%,达到了全国的平均水平。为了进一步发挥科技资源开发对河南经济增长的推动作用,建议河南继续加快科技资源的积累;重点提高科技资源配置的效率;特别重视大幅度提高对R&D的投入。 相似文献
174.
A. Bhagyalakshmi S. Venkata Reddy R. Ramamurthi P. S. Reddy 《Chemistry and Ecology》1995,11(2):97-104
Toxicity of an organochloride insecticide, hexachlorocyclohexane (HCH) on the alterations in the growth and silk qualities of silkworm, Bombyx mori L were investigated. HCH yielded higher growth constants (K), indicating impairment of growth of silkworms and silk gland. the decrement in fibroin content is significant. HCH treatment also resulted in considerable reduction in the cocoon, pupal and shell weights, survival and emergence of pupae and number of eggs laid and deterioration in quality and quantity of silk thread. 相似文献
175.
A case of confined placental mosaicism (CPM) and maternal uniparental isodisomy 14 identified after placental karyotype revealed trisomy 14 in a newborn with intrauterine growth restriction (IUGR) and minor dysmorphic features is reported. During the second trimester of the pregnancy, multiple marker screening revealed an increased risk for Down syndrome of >1 in 10. The maternal serum human chorionic gonadotrophin (MShCG) was markedly elevated at 4.19 MoM. Amniocentesis revealed a normal 46,XX karyotype. Fetal growth restriction has been associated with elevated MShCG and placental aneuploidy with CPM for chromosomes 2, 7, 9 and 16. The present case of CPM for chromosome 14 was also associated with fetal growth restriction and elevated second trimester MShCG, suggesting a common link. Further studies need to be done to determine if indeed elevation of second trimester MShCG is associated with increased risk of CPM. The present case again demonstrates the need to perform placental karyotype in unexplained fetal growth restriction. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
176.
Kirk Hamilton 《Environment, Development and Sustainability》2003,5(3-4):419-436
Genuine saving measures the real change in0 total wealth, factoring in the depreciation of produced assets, depletion of natural resources, pollution damages, and expenditures on education. This paper presents a theoretical framework for measuring changes in wealth in total and per capita terms, establishes the link between savings measures and prospects for social welfare, and provides summary empirical estimates of the savings measures. China excepted, the majority of countries below median income are distinguished by apparent declines in total wealth per capita. 相似文献
177.
The variations of the biochemical composition of Tetraselmis suecica and Isochrysis galbana during growth and decay were determined. the content of chlorophyll a (Chl-a) of the cultures, as expected, slowly degraded into phaeopigments during decay, confirming that chlorophyll measurements do not always provide an accurate estimate of phytoplanktonic biomass and, consequently, may fail if used to measure the food availability of particulate matter for consumers. Measurements of total amounts of proteins, carbohydrates and lipids, related to the nutritional value of particles in terms of caloric content, are shown to provide information on the readily available food for consumers, particularly during the blooms. the protein/carbohydrate, C/N and POC/Chl-a ratios were used to evaluate the differences between these two species during the growth and the decomposition processes. A comparison between experimental and field conditions was undertaken to implement our understanding of the growth and degradation processes of particulate organic matter of phytoplanktonic origin in the sea and its role on natural systems, during and after phytoplankton blooms. 相似文献
178.
中国经济增长对碳排放的影响分析 总被引:44,自引:1,他引:43
通过相关分析探讨了中国国内生产总值(GDP)的增长与碳排放量的关系.结果表明,二者有明显的相关性(R2=0.958 1).进一步研究认为,由于中国投资率在35%~40%以上,且工业增加值占GDP的比重超过50%,因此中国过分依赖投资的经济增长方式和以第二产业(工业)为主的经济结构在很大程度上是导致温室气体排放量增加的主要原因.未来在全球化背景下,经济增长可转变为更多地依靠科技创新、技术进步和制度的改进,因此,调整经济增长方式和产业结构,可以在保持发展经济的同时,使碳排放强度呈逐渐下降的趋势. 相似文献
179.
E. Vartiainen M. Kulmala T.M. Ruuskanen R. Taipale J. Rinne H. Vehkamki 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):7882-7892
Oxidation of d-limonene, which is a common monoterpene, can lead to new aerosol particle formation in indoor environments. Thus, products containing d-limonene, such as citrus fruits, air refresheners, household cleaning agents, and waxes, can act as indoor air aerosol particle sources. We released d-limonene into the room air by peeling oranges and measured the concentration of aerosol particles of three different size ranges. In addition, we measured the concentration of d-limonene, the oxidant, and the concentration of ozone, the oxidizing gas. Based on the measurements we calculated the growth rate of the small aerosol particles, which were 3–10 nm in diameter, to be about , and the losses of the aerosol particles that were due to the coagulation and condensation processes. From these, we further approximated the concentration of the condensable vapour and its source rate and then calculated the formation rate of the small aerosol particles. For the final result, we calculated the nucleation rate and the maximum number of molecules in a critical cluster. The nucleation rate was in the order of and the number of molecules in a critical-sized cluster became 1.2. The results were in agreement with the activation theory. 相似文献
180.
J. W. Lee 《国际发展与全球生态学杂志》2019,26(1):69-78
This paper examines long-run and short-run dynamics of renewable energy consumption on carbon dioxide (CO2) emissions and economic growth in the European Union. This study employs cointegration tests, Granger causality tests and vector error correction estimates to examine the direction of Granger causality, the long-run dynamics of economic growth and energy variables on carbon emissions. This study analyses time series data from the World Development Indicators over the period from1961 to 2012. The results of this study support a link between renewable energy consumption, economic growth, industrialization, exports and CO2 emissions in the long-run and short-run. The results support that the sign of the long-run dynamics from the endogenous variables to the CO2 emissions variable is negative and significant, which implies that the energy and environmental policies of the European Union aimed at curbing CO2 emissions must have been effective in the long-term. Furthermore, renewable energy consumption and exports have significant negative impact on CO2 emissions in the short-run. However, industrialization and economic growth have positive impact on CO2 emissions in the short-run. The results suggest that both economic growth and industrialization must have been achieved at the cost of harming the environment. The finding suggests that the increasing consumption of renewable energy tends to play an important role in curbing carbon emissions in the region. 相似文献