全文获取类型
收费全文 | 1139篇 |
免费 | 67篇 |
国内免费 | 227篇 |
专业分类
安全科学 | 161篇 |
废物处理 | 13篇 |
环保管理 | 109篇 |
综合类 | 717篇 |
基础理论 | 229篇 |
环境理论 | 1篇 |
污染及防治 | 68篇 |
评价与监测 | 39篇 |
社会与环境 | 47篇 |
灾害及防治 | 49篇 |
出版年
2024年 | 1篇 |
2023年 | 13篇 |
2022年 | 29篇 |
2021年 | 44篇 |
2020年 | 45篇 |
2019年 | 37篇 |
2018年 | 36篇 |
2017年 | 35篇 |
2016年 | 52篇 |
2015年 | 45篇 |
2014年 | 50篇 |
2013年 | 68篇 |
2012年 | 55篇 |
2011年 | 80篇 |
2010年 | 56篇 |
2009年 | 60篇 |
2008年 | 45篇 |
2007年 | 58篇 |
2006年 | 83篇 |
2005年 | 55篇 |
2004年 | 59篇 |
2003年 | 51篇 |
2002年 | 47篇 |
2001年 | 35篇 |
2000年 | 28篇 |
1999年 | 26篇 |
1998年 | 22篇 |
1997年 | 16篇 |
1996年 | 21篇 |
1995年 | 28篇 |
1994年 | 21篇 |
1993年 | 12篇 |
1992年 | 20篇 |
1991年 | 26篇 |
1990年 | 12篇 |
1989年 | 18篇 |
1988年 | 10篇 |
1987年 | 16篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1980年 | 1篇 |
排序方式: 共有1433条查询结果,搜索用时 15 毫秒
31.
A result that application of sodium selenite or fly ash to some of soilin loess plateau can increase Se content in wheat grain has been demonstrated by the pot and field experiments, and added Se in soil can last its availability for 3 years. So this is a good measure for improving the low Se soils and preventing the Kaschin-Beck disease. 相似文献
32.
Trung Pham Huu Yves Dumez Claude Marquetty Anne Durandy Joëlle Boue Jacques Hakim 《黑龙江环境通报》1987,7(4):253-260
Prenatal diagnosis of chronic granulomatous disease (CGD) was performed in four male high risk fetuses. The male sex was previously determined by an amniotic cell karyotype. Three kinds of test were performed on fetal blood obtained by umbilical venous puncture under fetoscopy at the 20th gestational week: nitroblue tetrazolium reduction (NBT) cytochemical test with phorbol myristate acetate (PMA) as activator; luminol enhanced chemiluminescence with activation by serum opsonized zymosan (STZ) or PMA; superoxide anion (0) production by measurement of the superoxide dismutase inhibitable reduction of cytochrome c with PMA as activator. Results were compared to those obtained in six fetuses investigated for other inherited diseases. In one case, absence of granulocyte defects was confirmed at birth. In three other cases, the tests showed deficient metabolic oxidative granulocytes. The pregnancy was terminated and the CGD diagnosis was confirmed on the products of abortion. The use of three different techniques performed on whole blood for CGD prenatal diagnosis is recommended instead of a single isolated test to ensure a higher confidence in the diagnosis. 相似文献
33.
34.
Isabella Delaroche Margherita Sabani Giuseppe Calabrese Rita Mingarelli Giandomenico Palka Professor Bruno Dallapiccola 《黑龙江环境通报》1995,15(3):278-281
An apparently balanced t(2q;21q) translocation was discovered in fetal blood and amniocytes of a 22-week fetus, monitored because of ultrasonographic evidence of a heart disease. FISH (fluorescence in situ hybridization) analysis disclosed a complex translocation between chromosomes 2q, 18q, and 21q, which was inherited from the healthy mother. This observation corroborates the usefulness of molecular cytogenetic techniques in raising the quality of prenatal diagnosis and detecting subtle rearrangements not resolved by standard cytogenetics. 相似文献
35.
Epidemiological survey of 573 families, clinical examination of 2593 persons, and X-ray examination of 1136 persons (in 16 typical endemic villages) were conducted, based on the classification of endemiology for KBD disease areas, i.e, mountain type, loess plateau type, plateau type, and flatlands type. It was revealed that the KBD disease areas exhibited the regular pattern of corming-into-being, development and passing-away and the characteristics of growth and decline. Further, it was found clinically that the disease areas may be divided into 4 types, i.e., recent onset, developing, stable, and historical. This division is simple and easy, practical, scientific, and reliable and can be applied by medical personnel at different levels. 相似文献
36.
37.
采用温锻制坯与冷摆辗相结合的复合成形工艺生产VE泵端面凸轮精密成形件,不仅材料利用率可达到95%左右;而且成形件的尺寸精度高,表面光洁度高,能有效地减少后续仿形磨削加工的余量,从而降低了生产成本,提高了生产效率。采用该工艺可以进行大批量生产,能满足我国轻型汽车VE泵的生产需要。 相似文献
38.
39.
L. Bovicelli M.D. F. M. Picchio G. Pilu G. Baccarani L. F. Orsini N. Rizzo G. Alampi P. M. Benenati J. C. Hobbins 《黑龙江环境通报》1984,4(1):67-72
In a case of fetal heart failure caused by endocardial fibroelastosis, prenatal echocardiography clearly demonstrated; a thickened endocardium. We therefore suggest that an abnormal endocardium may be detected in utero by ultrasound, thus representing an important clue in the differential diagnosis of fetal nonimmune hydrops and in the evaluation of pregnancies at risk for endocardial fibroelastosis. 相似文献
40.
本文论述了氢、氧同位素作为高岭土矿成因类型地球化学指标的意义.根据氢、氧同位素数据,我国浙闽沿海地区高岭土矿床主要可分为热液蚀变型和风化作用型两大类.其成矿溶液以大气降水为主. 相似文献