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941.
随着现代工程专业化水平和复杂程度的日益增长,高质量的项目管理已经成为目前大型工程顺利建成的重要保障之一。本文以苏州河环境整治工程项目管理工作为基础,通过对现代工程项目管理特点和重要性进行梳理、分析,论述了项目管理对大型工程的重要性,并根据实际工作经验,从项目信息管理、工作量统计、文明施工管理、工程档案管理等方面入手,成功完成该项目建设任务。结合所得工作成果,提出下一阶段项目管理工作的改进建议,所得成果极具现实意义。  相似文献   
942.
某公司硫酸生产线针对生产过程中存在的原材料消耗高、产品转化率低等问题,通过开展清洁生产审核,分析生产过程能耗、物耗、废物产生量的现状,从原辅材料和能源、工艺、设备、过程控制、管理、员工、产品及废物八个方面提出14个清洁生产方案,通过方案的实施,提高了公司清洁生产水平,实现了预防污染、节能降耗减污增效的目的。  相似文献   
943.
凤眼莲对铜绿微囊藻生长及藻毒素与营养盐释放的影响   总被引:4,自引:3,他引:1  
针对目前我国凤眼莲治理富营养化水体技术的规模化应用现状,考虑到大面积控养的凤眼莲与暴发的水华蓝藻(尤其是产毒铜绿微囊藻)会在湖湾区短期内密集共存的情况,开展了凤眼莲对产毒铜绿微囊藻生长、生理特性、藻毒素生产与释放影响的研究,另外,也考察了短期共存下藻类营养盐释放与凤眼莲对藻毒素积累的情况.半连续共培养实验结果表明,凤眼莲能够有效抑制铜绿微囊藻的生长,促进藻细胞的衰亡.虽然凤眼莲未对铜绿微囊藻光合系统Ⅱ的电子传递产生影响,但减少了其光合系统中的藻蓝蛋白(PC)含量和藻蓝蛋白/别藻蓝蛋白(PC/APC)水平,10%和20%水体交换率处理的PC/APC水平第8 d时分别降至相应空白对照的54.93%±7.07%和55.81%±1.97%.凤眼莲对铜绿微囊藻形成了一定的氧化伤害,最终促进其抗氧化系统中超氧化物歧化酶比活显著下降,丙二醛含量显著提高,10%和20%水体交换率处理的丙二醛含量第8d时分别升至相应空白对照的2.95倍±0.074倍和2.22倍±0.086倍.凤眼莲通过促进蓝藻的衰亡和分解,加速了营养盐的释放.12 d内,可溶性总氮浓度回升到初始水平,而水体可溶性总磷的释放速度比氮营养盐更快.另一方面,凤眼莲并没有促进铜绿微囊藻毒素的生产,也没有使水体藻毒素含量显著提高.相反,和自然衰减不同,短期内显著促进了水体藻毒素的降解,第12 d时10%和20%水体交换率处理的水体藻毒素分别下降至12.07μg·L-1±0.63μg·L-1和11.36μg·L-1±0.04μg·L-1.而凤眼莲整株的藻毒素短期积累量(FW)仅为5.95 ng·g-1±0.76 ng·g-1.增加水体交换率能够在一定程度上减缓凤眼莲对铜绿微囊藻的伤害,减缓营养盐的释放速度,但对水体藻毒素消减的影响不显著.  相似文献   
944.
隋秀文  邵帅  张芸  张树深 《环境科学学报》2014,34(10):2592-2598
本文研究水泥熟料生产过程中各个生产系统的效率,并对余热发电前后每个系统的效率进行分析对比,从而得出各个系统的资源能源利用程度以及余热发电工程对每个系统能量利用率的影响,诊断水泥熟料生产过程的损失发生位置并发现系统的节能和余热回收利用的潜力,为管理者实施节能降耗的方案提供技术支持.研究表明,实施余热发电工程前,水泥熟料生产的原料制备系统、煤粉制备系统、回转窑系统的效率分别为4.5%、1.4%和33.7%;实施余热发电工程后,效率分别为7.8%、2.8%和38.1%.余热发电工程可回收回转窑系统总投入的3.7%,同时使原料制备系统、煤粉制备系统、回转窑系统的效率分别提高3.3%、1.4%和4.3%.  相似文献   
945.
An alternating mesophilic and thermophilic two stage anaerobic digestion(AD) process was conducted. The temperature of the acidogenic(A) and methanogenic(M) reactors was controlled as follows: System 1(S1) mesophilic A-mesophilic M;(S2) mesophilic A-thermophilic M; and(S3)thermophilic A-mesophilic M. Initially, the AD reactor was acclimatized and inoculated with digester sludge. Food waste was added with the soluble chemical oxygen demand(SCOD) concentrations of41.4–47.0 g/L and volatile fatty acids of 2.0–3.2 g/L. Based on the results, the highest total chemical oxygen demand removal(86.6%) was recorded in S2 while S3 exhibited the highest SCOD removal(96.6%). Comparing S1 with S2, total solids removal increased by 0.5%; S3 on the other hand decreased by 0.1 % as compared to S1. However, volatile solids(VS) removal in S1, S2, and S3was 78.5%, 81.7%, and 79.2%, respectively. S2 also exhibited the highest CH4 content, yield, and production rate of 70.7%, 0.44 L CH4/g VSadded, and 1.23 L CH4/(L·day), respectively. Bacterial community structure revealed that the richness, diversity, evenness, and dominance of S2 were high except for the archaeal community. The terminal restriction fragments dendrogram also revealed that the microbial community of the acidogenic and methanogenic reactors in S2 was distinct. Therefore,S2 was the best among the systems for the operation of two-stage AD of food waste in terms of CH4production, nutrient removal, and microbial community structure.  相似文献   
946.
Previous measurements of peroxyacetyl nitrate(PAN) in Asian megacities were scarce and mainly conducted for relative short periods in summer. Here, we present and analyze the measurements of PAN, O3, NOx, etc., made at an urban site(CMA) in Beijing from 25 January to 22 March 2010. The hourly concentration of PAN averaged 0.70 × 10 9mol/mol(0.23 × 10 9–3.51 × 10 9mol/mol) and was well correlated with that of NO2but not O3, indicating that the variations of the winter concentrations of PAN and O3in urban Beijing are decoupled with each other. Wind conditions and transport of air masses exert very significant impacts on O3, PAN, and other species. Air masses arriving at the site originated either from the boundary layer over the highly polluted N-S-W sector or from the free troposphere over the W-N sector. The descending free-tropospheric air was rich in O3, with an average PAN/O3ratio smaller than 0.031, while the boundary layer air over the polluted sector contained higher levels of PAN and primary pollutants, with an average PAN/O3ratio of 0.11. These facts related with transport conditions can well explain the observed PAN-O3decoupling. Photochemical production is important to PAN in the winter over Beijing. The concentration of the peroxyacetyl(PA) radical was estimated to be in the range of 0.0014 × 10 12–0.0042 × 10 12 mol/mol. The contributions of the formation reaction and thermal decomposition to PAN's variation were calculated and found to be significant even in the colder period in air over Beijing, with the production exceeding the decomposition.  相似文献   
947.
Greater emphasis is being placed on indicators of agri-environmental efficiency of organic production systems. Linking environmental measures with profitability measures based on net income is the only way to develop such indicators. A stochastic production frontier model that explicitly incorporates farm decisions about acquiring and managing organic soil-improving inputs is used to measure efficiency. The results confirm that on-farm self-sufficiency in soil-improving inputs is positively related to farm-level efficiency.  相似文献   
948.
基于模糊综合评价法的建筑企业安全管理   总被引:5,自引:1,他引:4  
由于行业的自身特点,建筑企业安全管理一直是企业管理中的重点和难点。安全评价是企业进行安全管理的基础和依据,传统的安全评价方法,多为一些专家及安全管理人员凭经验得出的定性的结论,既缺乏系统科学的严谨性,在实践中又有很大的局限性。笔者在综合目前的安全评价技术的基础上,结合建筑行业特点,以《施工企业安全生产评价标准》(JGJ/T77—2003)为基础,提出了基于模糊综合理论的安全评价方法,并对该评价模型的的原理、方法进行了研究。该方法可以对不同企业或者同一企业的不同项目之间的安全现状做出量化评价,对促进企业安全管理工作的科学化、规范化、程序化有积极的现实意义。  相似文献   
949.
浅议建立清洁生产审核内审员制度   总被引:1,自引:1,他引:0  
阐述了建立内审员制度的必要性与意义.探讨了内审员的工作职能和管理与培训方法,为建立内审员制度提供了参考模式.  相似文献   
950.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   
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