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521.
皮托管平行测速法烟气监测方法的改进 总被引:1,自引:0,他引:1
将《环境监测技术规范》第二册中含湿量的测量方法进行了改进,并推导或给出了计算烟气结果的公式,使烟气监测更加快捷,更加准确。 相似文献
522.
The impact of astaxanthin-enriched algal powder on auxiliary memory improvement was assessed in BALB/c mice pre-supplemented
with different dosages of cracked green algal (Haematococcus pluvialis) powder daily for 30 days. The supplemented mice were first tested over 8 days to find a hidden platform by swimming in a
Morris water maze. Then, for 5 days, the mice were used to search for a visible platform in a Morris water maze. After that,
the mice practised finding a safe place—an insulated platform in a chamber—for 2 days. During these animal experimental periods,
similar algal meals containing astaxanthin at 0, 0.26, 1.3 and 6.4 mg/kg body weight were continuously fed to each group of
tested mice. Profiles of latency, distance, speed and the direction angle to the platforms as well as the diving frequency
in each group were measured and analyzed. The process of mice jumping up onto the insulated platform and diving down to the
copper-shuttered bottom with a 36 V electrical charge were also monitored by automatic video recording. The results of the
Morris maze experiment showed that middle dosage of H. pluvialis meals (1.3 mg astaxanthin/kg body weight) significantly shortened the latency and distance required for mice to find a hidden
platform. However, there was no obvious change in swim velocity in any of the supplemented groups. In contrast, the visible
platform test showed a significant increase in latency and swim distance, and a significant decrease in swim speed for all
groups of mice orally supplemented with H. pluvialis powder compared to the placebo group (P < 0.05 or P < 0.01). Mice supplemented with the algal meal hesitantly turned around the original hidden platform, in contract to mice
supplemented with placebo, who easily forgot the original location and accepted the visible platform as a new safe place.
These results illustrate that astaxanthin-enriched H. pluvialis powder has the auxiliary property of memory improvement. The results from the platform diving test showed that the low and
middle dosage of H. pluvialis powder, rather that the high dosage, increased the latency and reduced the frequency of diving from the safe insulated platform
to the electrically stimulated copper shutter, especially in the low treatment group (P < 0.05). These results indicate that H. pluvialis powder is associated with dose-dependent memory improvement and that a low dosage of algal powder (≤middle treatment group)
is really good for improving the memory. 相似文献
523.
524.
The present paper presents a quantitative approach to evaluate organizational resilience in sudden-onset disasters considering preparedness actions (PAs). The resilience triangle concept is extended and gradual improvement of the level of functionality (LF) strategy is examined as PAs. Robustness and rapidity measures are considered as loss of LF and recovery time to indicate the overall disaster resilience. Besides, the resourcefulness and redundancy measures are considered pre-determined response plans and PAs aimed to improve disaster resilience. Two mathematical models are developed by applying these measures. Thereafter, graphical analytics are conducted to demonstrate the effectiveness of PAs and provide a better outlook for decision-makers. Then, mathematical analyses are conducted to show how the PAs affect resilience measures. It is mathematically proved that PAs exert considerable impacts on recovery time, loss of LF, and robustness. To illustrate the application of the proposed approach, it is applied to an upstream oil and gas company in the field of exploration and production. The results suggest that the approach is significantly effective in disaster response, planning, and mitigation. 相似文献
525.
PROBLEM: Given the public safety risk posed by violation and crash repeaters and the substantial costs for state driver improvement programs, it is important that their effectiveness be scientifically demonstrated and that intervention programs are based on sound research findings. METHOD: Crash and traffic violation standardized effect sizes (d) representing 106 individual interventions were coded from 35 methodologically sound studies and analyzed using meta-analysis. RESULTS: Driver improvement intervention in general was associated with small but significant reductions in both crashes (dw = 0.03) and violations (dw = 0.06). Significant effects were found on both measures for warning letters, group meetings, individual hearings, and license suspense/revocation. Of the driver improvement interventions studied, license suspension/revocation was by far the most effective treatment for both crashes and violations (dw = 0.11 and 0.19). Since one of the objectives of license suspension/revocation is to eliminate driving for the period of suspension, it is possible that much or all of the effect is due to reduced exposure and/or more careful driving during the suspension interval. Results were mixed for other types of interventions, although distributing educational or informational material was not associated with any reductions. Interventions associated with violation reduction tended to also be associated with crash reduction, although the relationship was not very strong (r = .30). DISCUSSION: Although interpretation of the effect size estimates was complicated by almost ubiquitous heterogeneity, the results do suggest an overall positive impact of driver improvement interventions in general. IMPACT ON INDUSTRY: The results support the continued use of driver improvement interventions, chiefly warning letters, group meetings, individual hearings, and especially license suspension/revocation. The results also suggest that court-triggered traffic violator programs are less effective than interventions triggered by drivers license agencies. 相似文献
526.
四川省中低产田土的综合治理 总被引:1,自引:0,他引:1
本文以四川中低产田土综合治理实况为例,着重论述了自然灾害对农业生态系统的严重危害,从而阐明了改造中低产田土对提高经济、生态、社会三大效益的重要性和紧迫性,并从省情出发,总结提出当前乃至今后相当一个时期,农业部门所应采取的几项行之有效的措施,展望了2000年前景。 相似文献
527.
北运河是北京市重要的绿色生态走廊,贯穿联络京津冀协同发展多个关键节点.北运河主要由来自于城市污水处理厂排水等非常规水源补给,其水环境治理和水生态修复不仅是支撑京津冀生态文明建设的核心,而且是支撑北京城市副中心等重点区域水生态环境改善的重要环节.本专刊是国家水专项"北运河项目"团队近年来科研成果的总结,从"源-流-汇"全过程污染防控的角度出发,在"源削减"-多源污染防控、"流改善"-河流水质改善与生态修复、"汇景观"-库区水质改善与生态修复三个方面对研究和实践进行了梳理总结,以期为北运河流域绿色生态廊道构建提供科技支撑. 相似文献
528.
我国环境禁止令制度是当前禁令本土化的特殊表现,但面临着适用率畸低的制度虚置风险。制度成因是行为保全框架下的环境禁止令对实体权利救济关注不足,无法满足环境预防性保护的功能需求。我国环境预防性救济机制尚不完整,环境私益的保障强度不足。本文建议,应明确我国环境禁令的应然司法功能和社会功能。以完善环境禁令制度为依托,建立贯穿事前、事中、事后的风险预防性环境侵害救济机制。在公私法领域完善实体法依据并将环境禁令制度纳入民事诉讼法的特别程序。强化禁令适用中的法院职权,建立行政与司法衔接配合的执行保障机制。 相似文献
529.
河岸混合植物带处理受污染河水中试研究 总被引:21,自引:0,他引:21
利用2种混合植物带(香根草+沉水植物、湿生植物+香蒲+芦苇)对受污染河水进行中试研究,并与无植物空白带进行了对比.结果表明,混合植物带对污染物的降解效果优于无植物空白带,其中香根草+沉水植物带效果最好,它在整个运行期间对COD、NH4+-N和TP的去除率分别为43.5%、71.1%和69.3%.对出水溶解氧及水温进行了考察,结果表明混合植物带水域中水的溶解氧比无植物带稳定,且在夏季水温低于无植物带水域的水温.说明在河道修复中植物带对平衡河岸带环境条件、改善河流局部小气候有重要作用. 相似文献
530.
如何有效激活农民主体性,激发人居环境整治中的群众参与是实现农村环境善治的重要议题。村庄调研发现,在当前国家资源向村庄密集输入的情况下,自上而下的单一环境供给方式既浪费资源,又难以满足居民诉求。动员村庄女性群体组织化参与是农村人居环境整治自下而上的群众动员和需求整合的有效方式。一方面,女性群体因其身份在村、关系在村,市场参与不足,成为村庄环境整治的潜在力量,与环境治理事务具有耦合性。另一方面,组织化参与为女性社会性身份的展演提供长效机制,利益吸纳成为激发女性参与的直接诱因。女性群体参与人居整治实践机制反映的是以农民为主体的农村环境治理需要抓住核心力量,对积极分子进行识别、激活和组织。 相似文献