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1.
Tri(2-chloroethyl) phosphate (TCEP) with the initial concentration of 5 mg/L was degraded by UV/H2O2 oxidation process. The removal rate of TCEP in the UV/H2O2 system was 89.1% with the production of Cl? and PO43? of 0.23 and 0.64 mg/L. The removal rate of total organic carbon of the reaction was 48.8% and the pH reached 3.3 after the reaction. The oxidative degradation process of TCEP in the UV/H2O2 system obeyed the first order kinetic reaction with the apparent rate constant of 0.0025 min?1 (R2=0.9788). The intermediate products were isolated and identified by gas chromatography-mass spectrometer. The addition reaction of HO? and H2O and the oxidation reaction with H2O2 were found during the degradation pathway of 5 mg/L TCEP in the UV/H2O2 system. For the first time, environment risk was estimated via the “ecological structure activity relationships” program and acute and chronic toxicity changes of intermediate products were pointed out. The luminescence inhibition rate of photobacterium was used to evaluate the acute toxicity of intermediate products. The results showed that the toxicity of the intermediate products increased with the increase of reaction time, which may be due to the production of chlorine compounds. Some measures should be introduced to the UV/H2O2 system to remove the highly toxic Cl-containing compounds, such as a nanofiltration or reverse osmosis unit.  相似文献   
2.
A United Nations Framework Convention on Climate Change (UNFCCC) Joint Implementation (JI) host country has to make sure that JI projects are additional to avoid extra costs to generate the reductions necessary to cover the deduction of Emission Reduction Units (ERUs) from the country’s Kyoto Protocol emissions budget. A tender of ERUs by the government allows to generate additional reductions beyond the ERUs issued if it thoroughly checks project additionality. The government of New Zealand is running a tender for JI projects under the title “Projects to Reduce Emissions” since 2003. In two rounds, 10 million ERUs have been awarded and several projects have already entered into contracts with European buyers. The ratio of ERUs awarded to reductions achieved was 0.8 in the second tender. However it remains to be seen whether the additionality test of this tender is sufficient to exclude clearly non-additional projects.  相似文献   
3.
对情境意识的定义、活动机制、测量方法及强化方法等进行了述评。分析了关于情境意识研究的问题及趋势。  相似文献   
4.
Recent debates regarding the criteria for evaluating occupational health and safety interventions have focused on the need for incorporating qualitative elements and process evaluation, in addition to attempting to live up to the Cochrane criteria. Reflecting fundamental epistemological conflicts and shortcomings of the Cochrane criteria in evaluating intervention studies, the debate challenges the traditional (quasi-) experimental design and methodology, which are often used within safety research. This article discusses a revised ‘realistic evaluation’ approach as a way to meet these challenges.Evidence from the literature as well as examples from an integrated (leader-based/worker-based) safety intervention study (2008-2010) in a large wood manufacturing company are presented, with focus on the pros and cons of using randomised-controlled-trials and a revised realistic evaluation model.A revised realistic evaluation model is provided which includes factors such as role behaviour, leader and worker motivation, underreporting of accidents/injuries, production pressure, unplanned organisational change and accounting for multilayer effects. These can be attained through qualitative and/or quantitative methods, allowing for the use of realistic evaluation in both large and small scale studies, as well as in systematic reviews. The revised realistic evaluation model offers a promising new way of designing and evaluating occupational safety research. This model can help safety science move forward in setting qualitative and/or quantitative criteria regarding context, mechanisms and processes for single studies and for reviews. Focus is not limited to whether the expected results appear or not, but include suggestions for what works for whom, under what circumstances, in what respects and how.  相似文献   
5.
微生物絮凝剂   总被引:26,自引:0,他引:26  
综述了微生物絮凝剂的产生和培养条件 ,同时讨论了微生物絮凝剂的絮凝反应条件 ,反应机理和在废水处理中的应用 ,提供了今后的研究方向。  相似文献   
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The formation of covalent binding to DNA of a carcinogen is now widely accepted to represent a classical mechanism of tumour induction in mammals. This mechanism does not operate with metals since no covalent binding of these agents to DNA does occur. Nevertheless, somatic mutations as typical consequences of DNA‐damage have been reported to be induced by metals in various model systems. Beside DNA‐alkylation such damages can be caused by changes in the conformation of DNA or in the fidelity of DNA‐repair. The activity of the repair enzymes DNA‐polymerases is indeed impaired by many metal ions at least in vitro. It is not yet established whether these mechanisms are also important in the intact mammalian organism. Much evidence has accumulated during the last years that a disturbance of the balance of cations and especially metal ions represents another possible mechanism of tumour induction. The tumours found with high doses of chelating agents such as nitrilo‐triacetic acid (NTA) have to be discussed in this context. Since most—if not—all of the speculative mechanisms of metal carcinogenesis resemble classical pharmacological reactions the existence of a threshold level is likely. So metal carcinogenesis will not be a problem of the environmental contamination at trace levels but a problem of occupational medicine.  相似文献   
8.
文章通过对联合国环境署制订的用于工业废水处理项目中实施清洁发展机制(CDM)合格性识别的方法学进行分析,以及根据项目建议书和官方网站信息统计归纳的国外工业废水处理项目CDM开发的成功案例,并结合中国工业废水氧化塘处理法的现状情况,对中国工业废水尤其是高浓度有机废水处理中CDM项目开发机会进行了探索性的研究,提出在食品工业尤其是酒精废水、淀粉废水、酿酒废水的处理过程中开展CDM项目的可行性。以此对中国工业废水中CDM项目的未来开发情况进行了设想与建议。  相似文献   
9.
Pendulum impacts on the back were conducted to determine human head, neck and torso biomechanics. Eight unembalmed cadavers were subjected to 23.4 kg pendulum impacts at 4.4 m/s and 6.6 m/s at T1 and T6. Twenty-four tests were conducted with accelerometers on the pendulum, spine, torso, and head in the WSU 3-2-2-2 array. High-speed photography was taken. Impact displaces the torso forward, deflects the chest, displaces and rotates the head, and extends the neck. Average responses and corridors were determined for head kinematics and chest force-deflection. The head-neck response occurs in two phases. First, the head displaces upwards and rearwards 30—40 mm with respect to the torso along a 45° trajectory. Head rotation is 1O°-15° with essentially no neck moment, but high neck compression forces. Second, the head rotates from 10°-15° to 40°-55° starting with a rapid rise in neck moment and displaces 80–100 mm rearward. Anterior cervical fractures correlate with neck tension. Rib fractures correlate with impact force and chest deflection. This study provides chest bio-mechanical responses for rear impacts resulting in head displacement and rotation, neck extension and cervical-thoracic injury.  相似文献   
10.
宁镇山脉岩基中四个花岗岩类杂岩体具分带性。水平分带表现在单个杂岩体从边缘向核部的结晶顺序总是为:石英闪长岩→石英二长岩(花岗闪长岩)→二长花岗岩,斑晶含量随岩石酸度增加而降低,以致由斑状结构演化为等粒状结构,岩浆定位后的对流作用是这种水平分带的主要机理。与岩浆房内部对流结合起来的边界层环流作用使富钾流体在高位富集,导致晚期分异熔体从早期结晶外壳冲破出来移向高处而具垂直分带。认为每个杂岩体代表一批同源岩浆的演化系列或一个超单元。  相似文献   
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