全文获取类型
收费全文 | 1690篇 |
免费 | 16篇 |
国内免费 | 71篇 |
专业分类
安全科学 | 76篇 |
废物处理 | 186篇 |
环保管理 | 183篇 |
综合类 | 160篇 |
基础理论 | 277篇 |
环境理论 | 2篇 |
污染及防治 | 651篇 |
评价与监测 | 163篇 |
社会与环境 | 63篇 |
灾害及防治 | 16篇 |
出版年
2023年 | 20篇 |
2022年 | 37篇 |
2021年 | 36篇 |
2020年 | 15篇 |
2019年 | 29篇 |
2018年 | 44篇 |
2017年 | 58篇 |
2016年 | 81篇 |
2015年 | 42篇 |
2014年 | 71篇 |
2013年 | 140篇 |
2012年 | 105篇 |
2011年 | 119篇 |
2010年 | 96篇 |
2009年 | 109篇 |
2008年 | 123篇 |
2007年 | 108篇 |
2006年 | 101篇 |
2005年 | 87篇 |
2004年 | 83篇 |
2003年 | 57篇 |
2002年 | 62篇 |
2001年 | 47篇 |
2000年 | 21篇 |
1999年 | 12篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1777条查询结果,搜索用时 734 毫秒
431.
Un Bong Baek Kwon Sang Ryu Amkee Kim Seung Hoon Nahm 《Journal of Loss Prevention in the Process Industries》2009,22(6):971-974
Many researchers have been interested in the nondestructive measurement methods for estimating components damage in order to assure the safe service of steel structures. It is recognized that the evaluating techniques based on magnetic measurement can offer a great potential because of high susceptibility to the change of several metallurgical factors. Magnetic property such as coercive force was measured. The coercive force at room temperature monotonously increased with the increase of frequency. The correlation between the magnetic properties of used material and that of un-used material was studied. The coercive force gradient at room temperature increased with the increase of aging. Hence the estimating method using magnetic properties allows one to evaluate the extent of material aging for reactor pressure vessel. 相似文献
432.
Manila clams, Ruditapes philippinarum, removed from their natural environment and maintained for 9 weeks in continuously immersed conditions exhibited a clear
endogenous circatidal rhythm in oxygen consumption. The clams exhibited a semidiurnal rhythmicity in oxygen consumption after
showing a diurnal pattern in the first few days (5 to 7 d) of the experiment. The results of the present study indicate that
activity rhythms of clams are controlled not only by exogenous factors, but also by an endogenous circatidal periodicity.
Received: 8 April 1998 / Accepted: 1 February 1999 相似文献
433.
434.
Successful outcome following prenatal intervention in a female fetus with bladder outlet obstruction
Eui Jung Hye-Sung Won Jae-Yoon Shim Pil Ryang Lee Ahm Kim Kun Suk Kim 《黑龙江环境通报》2005,25(12):1107-1110
Bladder outlet obstructions are a diverse and heterogeneous group of developmental abnormalities that generally involve obstruction of the proximal urethra in the male fetus. Indications for prenatal intervention are few and are usually restricted to the male fetus because bladder outlet obstruction in female fetuses is usually caused by complex cloacal development anomalies. We report on a female fetus with an enlarged bladder and a dilated proximal urethra (known as typical keyhole sign). A vesicoamniotic shunt was performed despite non-reassuring prognostic factors, but the procedure resulted in a successful outcome. We propose that in selected cases of bladder outlet obstruction, fetal intervention should be considered even when the fetus is female. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
435.
436.
Eben Goodale Edward Kim Annika Nabors Sara Henrichon James C. Nieh 《Die Naturwissenschaften》2014,101(6):523-526
Nectar guides can enhance pollinator efficiency and plant fitness by allowing pollinators to more rapidly find and remember the location of floral nectar. We tested if a radiating nectar guide around a nectary would enhance the ability of naïve bumble bee foragers to find nectar. Most experiments that test nectar guide efficacy, specifically radiating linear guides, have used guides positioned around the center of a radially symmetric flower, where nectaries are often found. However, the flower center may be intrinsically attractive. We therefore used an off-center guide and nectary and compared “conjunct” feeders with a nectar guide surrounding the nectary to “disjunct” feeders with a nectar guide separated from the nectary. We focused on the innate response of novice bee foragers that had never previously visited such feeders. We hypothesized that a disjunct nectar guide would conflict with the visual information provided by the nectary and negatively affect foraging. Approximately, equal numbers of bumble bees (Bombus impatiens) found nectar on both feeder types. On disjunct feeders, however, unsuccessful foragers spent significantly more time (on average 1.6-fold longer) searching for nectar than any other forager group. Successful foragers on disjunct feeders approached these feeders from random directions unlike successful foragers on conjunct feeders, which preferentially approached the combined nectary and nectar guide. Thus, the nectary and a surrounding nectar guide can be considered a combination of two signals that attract naïve foragers even when not in the floral center. 相似文献
437.
Recovery of iron oxide and calcium chloride from an iron-rich chloride waste using calcium carbonate
Yang Hee Jung Yoon Seok Won Kim You Jin Park Hee Sun Huh Seok Hur Nam Hwi 《Journal of Material Cycles and Waste Management》2021,23(1):222-230
Journal of Material Cycles and Waste Management - The ilmenite-chloride process has used for the production of TiCl4 from the ilmenite (FeTiO3) ore, which produces cyclone dust containing mostly... 相似文献
438.
Liem T. Tran Ryan McManamay Hyun Kim 《Journal of Environmental Planning and Management》2019,62(5):766-778
The paper presents a multivariate measure useful for integrated environmental assessments. It is a weighted distance measure applied to metric data but based on nonparametric statistical procedures. The proposed measure allows all environmental indicators to be used directly without any reduction in dimension (e.g. as in principal component analysis) nor losing variance while being able to tolerate possible non-normality of the indicators, as well as non-linear relationships among them. Results of the hypothetical example and the Mid-Atlantic case study show that the proposed measure is suitable and valuable for integrating multiple indicators into a single index, an important task in integrated environmental assessment. 相似文献
439.
K. W. Kim 《Behavioral ecology and sociobiology》2000,48(3):182-187
This study investigates proximate factors influencing dispersal behaviour in the subsocial spider Amaurobius ferox. Dispersal of spiderlings from the natal web occurred as a progressive sigmoidal function (mean duration of dispersal period=31
days), with considerable individual variability in developmental instar and body mass within the clutch at the time of dispersal.
The spiderlings showed a significant decrease in group cohesion on the 6th day after their second moult, which corresponded
to the beginning of the dispersal period. Mutual aggressiveness appeared when the spiderlings began to show predatory behaviour
(4th day post-second moult) and increased over the course of the dispersal period. While lack of prey in the maternal nest
accelerated dispersal behaviour, the addition of prey items lengthened the dispersal period in previously non-fed clutches.
Individuals that dispersed were smaller than the remaining individuals when measured on the day 50% of the clutch had dispersed.
Timing of the appearance of the developmental characters (second moult, predation activity, agonistic behaviour against siblings,
reduction of group cohesion, dispersal) suggests that the dispersal trait might have evolved in consequence of these different
functional behaviours.
Received: 10 August 1999 / Received in revised form: 15 March 2000 / Accepted: 1 April 2000 相似文献
440.
Tai-Yoo Kim Seung-Jun Kwak Seung-Hoon Yoo 《Journal of Environmental Planning and Management》1998,41(5):597-609
This paper applies the multi-attribute utility theory (MAUT) to obtaining value judgments concerning the significance of environmental impacts to achieve integration of environmental concerns at an early stage of planning, using the electric utility of Korea as a specific case study. An environmental multi-attribute index is constructed as a multi-attribute utility function, based on value judgments provided by a group of experts related to electric utility and a decision maker from Korea Electric Power Corporation (KEPCO). The societal values are derived from examining trade-offs between environmentalindex and money. The implications of the results for KEPCO are also discussed. We found that the work and results can provide valuable insights and decision opportunities for major decision making in environmental planning facing KEPCO. 相似文献