全文获取类型
收费全文 | 1284篇 |
免费 | 15篇 |
国内免费 | 15篇 |
专业分类
安全科学 | 32篇 |
废物处理 | 75篇 |
环保管理 | 122篇 |
综合类 | 191篇 |
基础理论 | 255篇 |
污染及防治 | 432篇 |
评价与监测 | 117篇 |
社会与环境 | 85篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 20篇 |
2022年 | 42篇 |
2021年 | 31篇 |
2020年 | 22篇 |
2019年 | 19篇 |
2018年 | 45篇 |
2017年 | 48篇 |
2016年 | 64篇 |
2015年 | 38篇 |
2014年 | 76篇 |
2013年 | 123篇 |
2012年 | 93篇 |
2011年 | 112篇 |
2010年 | 64篇 |
2009年 | 71篇 |
2008年 | 82篇 |
2007年 | 67篇 |
2006年 | 59篇 |
2005年 | 62篇 |
2004年 | 36篇 |
2003年 | 39篇 |
2002年 | 17篇 |
2001年 | 14篇 |
2000年 | 12篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 7篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1986年 | 3篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有1314条查询结果,搜索用时 218 毫秒
821.
822.
Valentina Ciardelli Nicola Rizzo Antonio Farina Marisa Vitarelli Paola Boni Luciano Bovicelli 《黑龙江环境通报》2001,21(7):586-588
The relationship between fetal renal function (FRF) and fetal serum beta2-microglobulin (B2MG) was investigated by comparing its value in 112 unaffected fetuses with that of 23 fetuses presenting with urinary tract malformations (UTM). Fetal serum level of B2MG was totally unrelated to gestational age; its value increased in cases of severe impairment of FRF but was similar to controls in all mild uropathies (p<0.05). Evaluating serum B2MG could be beneficial in fetuses with severe renal damage, but is of no use in unilateral UTM since only the global FRF is tested and not the function of each single kidney. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
823.
Laura Braida Sergio Crovella Michele Boniotto Ariella Luchesi Umberto de Vonderweid Bruno Casetta Antonio Amoroso 《黑龙江环境通报》2001,21(7):543-546
We describe a quantitative, rapid, sensitive and reproducible tandem mass spectrometry (MSMS) method for the one-step detection of aminoacid (AAs) and acylcarnitine (ACs) concentrations in amniotic fluid. This technology is quicker and more sensitive than other methods used to date since it is possible to determine very low AA and AC concentrations in samples simultaneously in a single run. The high degree of automation allows a large number of pregnancies to be screened for metabolic defects in a very short time. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
824.
In addition to heat production on the comb surface, honeybee workers frequently visit open cells (“gaps”) that are scattered
throughout the sealed brood area, and enter them to incubate adjacent brood cells. We examined the efficiency of this heating
strategy under different environmental conditions and for gap proportions from 0 to 50%. For gap proportions from 4 to 10%,
which are common to healthy colonies, we find a significant reduction in the incubation time per brood cell to maintain the
correct temperature. The savings make up 18 to 37% of the time, which would be required for this task in completely sealed
brood areas without any gaps. For unnatural high proportions of gaps (>20%), which may be the result of inbreeding or indicate
a poor condition of the colony, brood nest thermoregulation becomes less efficient, and the incubation time per brood cell
has to increase to maintain breeding temperature. Although the presence of gaps is not essential to maintain an optimal brood
nest temperature, a small number of gaps make heating more economical by reducing the time and energy that must be spent on
this vital task. As the benefit depends on the availability, spatial distribution and usage of gaps by the bees, further studies
need to show the extent to which these results apply to real colonies.
M. Fehler and M. Kleinhenz contributed equally to this work. 相似文献
825.
Arzarello M Marcolini F Pavia G Pavia M Petronio C Petrucci M Rook L Sardella R 《Die Naturwissenschaften》2007,94(2):107-112
Some flint lithic artifacts were discovered in the fissure fillings of the well-known Pirro Nord site (Apulia, Southern Italy).
The lithic industry, composed by three cores and some flakes, has been found to be associated to an Early Pleistocene vertebrate
fossil assemblage. The fossil association contains a wide range of micromammals, including Allophaiomys ruffoi and Episoriculus gibberodon and large mammals including Bison degiulii and Equus altidens together with African elements as the gelada baboon Theropithecus and the saber-toothed cat Megantereon whitei. It defines the latest Villafranchian chronological unit (Pirro Nord Faunal Unit) in the Western European mammal biochronology.
The lithic industry of Pirro Nord represents the oldest occurrence of the genus Homo in Europe as it is attributable to a chronological interval between 1.3 and 1.7 Ma. This supports the hypothesis that the
genus Homo, with Oldowaian technology, extended its range in Europe, probably from western Asia, during the first half of the Early
Pleistocene. The new discovery from Pirro Nord changes the chronology of the first arrival of hominids in Europe and offers
new perspectives in the debate about the human dispersal in the Early Pleistocene. 相似文献
826.
827.
Vulnerability of Soil and Its Associated Organic Matter to Degradation in a Subtropical Region: A Study From São Paulo State,Brazil
下载免费PDF全文
![点击此处可从《环境质量管理》网站下载免费的PDF全文](/ch/ext_images/free.gif)
828.
Sabrina Portofino Antonio Donatelli Pierpaolo Iovane Carolina Innella Rocco Civita Maria Martino Domenico Antonio Matera Antonio Russo Giacinto Cornacchia Sergio Galvagno 《Waste management (New York, N.Y.)》2013,33(3):672-678
An experimental survey of waste tyre gasification with steam as oxidizing agent has been conducted in a continuous bench scale reactor, with the aim of studying the influence of the process temperature on the yield and the composition of the products; the tests have been performed at three different temperatures, in the range of 850–1000 °C, holding all the other operational parameters (pressure, carrier gas flow, solid residence time). The experimental results show that the process seems promising in view of obtaining a good quality syngas, indicating that a higher temperature results in a higher syngas production (86 wt%) and a lower char yield, due to an enhancement of the solid–gas phase reactions with the temperature. Higher temperatures clearly result in higher hydrogen concentrations: the hydrogen content rapidly increases, attaining values higher than 65% v/v, while methane and ethylene gradually decrease over the range of the temperatures; carbon monoxide and dioxide instead, after an initial increase, show a nearly constant concentration at 1000 °C. Furthermore, in regards to the elemental composition of the synthesis gas, as the temperature increases, the carbon content continuously decreases, while the oxygen content increases; the hydrogen, being the main component of the gas fraction and having a small atomic weight, is responsible for the progressive reduction of the gas density at higher temperature. 相似文献
829.
Vincenzo Torretta Marco Ragazzi Irina Aura Istrate Elena Cristina Rada 《Waste management (New York, N.Y.)》2013,33(1):117-122
The paper presents some data regarding waste electrical and electronic (WEEE) management in one of the founding countries of the EU, Italy, and in a recent entry into the EU, Romania. The aim of this research was to analyze some problems that countries entering the EU will have to solve with respect to WEEE management. The experiences of Italy and Romania could provide an interesting reference point. The strengths and weaknesses that the two EU countries have encountered can be used in order to give a more rational plan for other countries. In Italy the increase of WEEE collection was achieved in parallel with the increase of the efficiency of selective Municipal Solid Waste collection. In Romania, pilot experiences were useful to increase the awareness of the population. The different interests of the two populations towards recyclable waste led to a different scenario: in Romania all types of WEEE have been collected since its entrance into the EU; in Italy the “interest” in recycling is typically related to large household appliances, with a secondary role of lighting equipment. 相似文献
830.
Marco Ferretti Enrico Cenni Filippo Bussotti Paolo Batistoni 《Chemistry and Ecology》2013,29(4):213-228
Lead and cadmium concentrations in spontaneous vegetation and in soil sampled at various distances (0–208 m) from several motorways throughout Italy were measured. Lead and cadmium concentrations appear to be correlated to distance from the motorway and to traffic levels. A comparison with data from a remote and unpolluted site shows that foliar lead concentrations can be up to 40 times higher, and foliar cadmium concentrations up to 3 times higher. Plants behave differently in their accumulation of lead and cadmium; conifers present the highest levels. Also the various receptors and compartments of the roadside ecosystem differ in their accumulation of lead and cadmium; soil and bark have consistently higher concentrations, while the leaves and twigs of trees have consistently lower levels. the data recorded by ad hoc introduced bio-accumulating plants (Lolium multiflorum L.) are consistent with those of the spontaneous vegetation. the concentrations of both lead and cadmium in Lolium vary from June to November, following in part the fluctuation in traffic density. 相似文献