全文获取类型
收费全文 | 1673篇 |
免费 | 36篇 |
国内免费 | 153篇 |
专业分类
安全科学 | 34篇 |
废物处理 | 20篇 |
环保管理 | 245篇 |
综合类 | 515篇 |
基础理论 | 235篇 |
污染及防治 | 495篇 |
评价与监测 | 241篇 |
社会与环境 | 62篇 |
灾害及防治 | 15篇 |
出版年
2024年 | 5篇 |
2023年 | 14篇 |
2022年 | 19篇 |
2021年 | 35篇 |
2020年 | 53篇 |
2019年 | 27篇 |
2018年 | 46篇 |
2017年 | 33篇 |
2016年 | 51篇 |
2015年 | 58篇 |
2014年 | 50篇 |
2013年 | 121篇 |
2012年 | 91篇 |
2011年 | 184篇 |
2010年 | 106篇 |
2009年 | 186篇 |
2008年 | 164篇 |
2007年 | 132篇 |
2006年 | 76篇 |
2005年 | 46篇 |
2004年 | 36篇 |
2003年 | 50篇 |
2002年 | 36篇 |
2001年 | 26篇 |
2000年 | 36篇 |
1999年 | 20篇 |
1998年 | 16篇 |
1997年 | 16篇 |
1996年 | 20篇 |
1995年 | 11篇 |
1994年 | 16篇 |
1993年 | 28篇 |
1992年 | 19篇 |
1991年 | 3篇 |
1990年 | 8篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有1862条查询结果,搜索用时 500 毫秒
931.
介绍了大冶有色金属公司饮料厂汽水车间地基土发生胀害原因的调查及试验分析。揭示了该地基土因受化学污染发生膨胀的机理,为治理已有裂缝和防止裂缝进一步发展,确保该建筑物安全使用提供了依据。 相似文献
932.
933.
To investigate whether wind is a significant driving force in the diffusion of CO and CH4 from the atmosphere into soil, we measured the concentrations of these two gases at two heights above a temperate grass field in Japan and estimated their deposition velocities using micrometeorological techniques. The concentrations were inversely correlated with wind speed, indicating that the local concentrations were influenced by ground sources. The CO and CH4 concentrations at 0.33 m were usually lower than those at 1.3 m. Although nocturnal data are suspected to be non-stationary, by selecting several periods when the changes of the concentrations were small but larger than analytical precision, we obtained a CO velocity of 2.9 and 3.9×10−2 cms−1, agreeing with a CO deposition velocity, 3.4×10−2 cms−1, obtained by applying a method using CO2 as a tracer. The CH4 influx obtained by the method using CO2 as a tracer was 13 ngm−2 s−1. The ranges of the CO deposition velocity and CH4 influx were similar to those obtained in previous studies in grassfields and in a nearby arable field using a closed-chamber technique. This shows that light winds do not greatly accelerate CO and CH4 uptake by soil. 相似文献
934.
探究4种改良剂施用对酸性紫色土土壤肥力及活性碳组分特征影响,为紫色土养分管理及稳固碳库提供科学依据.采用田间试验,设置不施肥(CK)、单施化肥(F)、石灰+化肥(SF)、有机肥+化肥(OM)、生物炭+化肥(BF)及酒糟灰渣+化肥(JZ)这6个处理,研究不同处理土壤有机质、pH、速效养分、土壤综合肥力指数(IFI)、溶解性有机碳(DOC)、微生物量碳(MBC)、颗粒有机碳(POC)含量及各组分有效率和土壤碳库管理指数(CPMI),阐明其相互关系.结果表明:①施用改良剂显著提高了土壤pH及有机质、碱解氮、速效磷、速效钾含量(P<0.05),有机肥+化肥(OM)和酒糟灰渣+化肥(JZ)处理土壤综合肥力指数提高最为显著(P<0.05),较对照分别提高了1.96和0.77,增幅分别为170.43%和66.96%.②酒糟灰渣+化肥(JZ)和有机肥+化肥(OM)处理土壤POC、MBC和DOC含量较对照处理分别提高了110.30%和84.81%、61.08%和46.56%、195.87%和141.67%;改良剂的施用均显著提高了土壤碳库指数(CPI)和碳库管理指数(CMPI)(P<0.05),其中以有机肥+化肥(OM)处理提高最为显著,土壤CPI值和CMPI值较对照分别增加了107.34%和90.75%.③土壤有机碳及其活性组分与土壤综合肥力指数呈显著正相关(P<0.05),冗余分析表明施用改良剂各处理间分异性显著,土壤IFI、pH和速效钾对有机碳及其组分的解释率均达到显著水平,解释率顺序分别为:IFI(74.6%)>pH(11.7%)>AK(6.5%).酸性紫色土施用酒糟灰渣和有机肥提高土壤肥力和改良土壤质量效果最显著,同时有利于促进土壤碳组分的积累和活化. 相似文献
935.
In the indoor environment, settled surface dust often functions as a reservoir of hazardous particulate contaminants. In many
circumstances, a major contributing source to the dust pool is exterior soil. Young children are particularly susceptible
to exposure to both outdoor derived soil and indoor derived dust present in the indoor dust pool. This is because early in
life the exploratory activities of the infant are dominated by touching and mouthing behavior. Inadvertent exposure to dust
through mouth contact and hand-to-mouth activity is an inevitable consequence of infant development. Clean-up of indoor dust
is, in many circumstances, critically important in efforts to minimize pediatric exposure. In this study, we examine the efficiency
of vacuum cleaner removal of footwear-deposited soil on vinyl floor tiles. The study utilized a 5 × 10 foot (c. 152.5 × 305 cm)
test surface composed of 1-foot-square (c. 30.5 × 30.5 cm) vinyl floor tiles. A composite test soil with moderately elevated
levels of certain elements (e.g., Pb) was repeatedly introduced onto the floor surface by footwear track-on. The deposited
soil was subsequently periodically removed from randomly selected tiles using a domestic vacuum cleaner. The mass and loading
of soil elements on the tiles following vacuuming were determined both by wet wipe collection and by subsequent chemical analysis.
It was found that vacuum cleaner removal eliminated much of the soil mass from the floor tiles. However, a small percentage
of the mass was not removed and a portion of this residual mass could be picked up by moistened hand-lifts. Furthermore, although
the post-vacuuming tile soil mass was sizably reduced, for some elements (notably Pb) the concentration in the residual soil
was increased. We interpret this increased metal concentration to be a particle size effect with smaller particles (with a
proportionately higher metal content) remaining in situ after vacuuming. 相似文献
936.
In this work a two-stage process combining soil electrokinetic remediation and liquid electrochemical oxidation for the remediation
of polluted soil with organic compounds has been developed and evaluated using phenanthrene-spiked kaolinite. Application
of an unenhanced electrokinetic process resulted in negligible removal of phenanthrene from the kaolinite sample. Addition
of co-solvents and electrolyte to the processing fluid used in the electrode chambers enhanced phenanthrene desorption from
the kaolinite matrix and favoured electro-osmotic flow. Near-complete removal of phenanthrene was achieved using Na2SO4 and ethanol in the processing fluid. Phenanthrene was transported towards the cathode chamber where it was collected. The
cathodic solution containing the pollutant was treated by electrochemical oxidation; complete degradation of phenanthrene
occurred after 9 h using Na2SO4 as electrolyte. 相似文献
937.
Nieto Castillo AM Soriano JJ García-Delgado RA 《Environmental geochemistry and health》2008,30(2):153-157
A laboratory study has been carried out to determine the feasibility of in situ remediation of chromium (VI)-contaminated
soil using electrodialysis in relation to its speciation in soil. This technique is best suited for low-permeability soils
or sediments, which may be difficult to remediate by other means and implies the application of a low-intensity direct current
to the soil, which is separated from the electrode compartments by ion-exchange membranes. A clayey soil was prepared for
use in the experiments and was characterized before being mixed with a solution of potassium dichromate for several days to
produce a final Cr content of 4,056 mg/kg of soil dry wt. Remediation tests were carried out under constant-voltage conditions
for periods of 7–14 days and the evolution of applied current to the cell, pH, and conductivity of the electrolytes were recorded
periodically. Fractionation of chromium was determined for soil samples before and after remediation using a standardized
four-step sequential extraction procedure (SEP) with acetic acid, hydroxylamine, hydrogen peroxide, and aqua regia solutions.
Results show that chromium is mobilized from the most labile phases (soluble/exchangeable/carbonate). In a 15 V test, SEP
results show that the amount of chromium extracted in the first step drops from 80% to 9%, but also that changes in the total
chromium distribution occur during the treatment with some transferred to other soil phases that are more difficult to mobilize. 相似文献
938.
本文以某化肥厂场地为例,经过现场分析与场地污染识别分区结果,该区域内的地下水埋深在47m左右,本次调查中场地未揭露地下水。调查共分6个区域对样品的重金属类、石油烃类、VOC类、VOCs类、氰化物、硝酸盐及亚硝酸盐、氨氮及游离氨类进行了初步筛查;场地内的氨氮及游离氨有大量检出,在超标区域及附近区域需进行详细调查,增加点位,针对氨氮及游离氨进行采样分析。 相似文献
939.
940.
土壤环境污染问题一直是困扰我国社会经济发展的重要难题,随着科学技术的不断进步,土壤环境污染修复技术也取得了创新与进步。化学修复是土壤环境污染修复的重要举措,同时多样化的化学修复技术为土壤环境污染问题提供了更加科学与合理的修复途径,因此化学修复具有较强的适用性。本文就土壤环境污染化学及化学修复技术进行全面探讨和研究,希望推动相关领域的创新发展。 相似文献