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121.
研究开发了基于Web的城市污水处理厂决策支持系统(模拟系统、专家系统、培训系统),实现了决策支持中心的思想。介绍了城市污水处理厂Web决策支持中心的设计思想,以及利用.NET技术,以单机版决策支持系统为基础进行软件开发的方法。同时讨论了开发城市污水处理厂决策支持中心的意义,以及在本研究基础上进行深入科研工作的前景。  相似文献   
122.
  总被引:2,自引:0,他引:2  
The selection of cadmium-excluding cultivars has been used to minimize the transfer of cadmium into the human food chain. In this experiment, five Chinese soybean plants were grown in three soils with different concentrations of Cd (0.15, 0.75 and 1.12 mg/kg). Variations in uptake, enrichment, and translocation of Cd among these soybean cultivars were studied. The results indicated that the concentration of Cd in seeds that grew at 1.12 mg/kg Cd in soils exceeded the permitted maximum levels in soybeans. Therefore, our results indicated that even some soybean cultivars grown on soils with permitted levels of Cd might accumulate higher concentrations of Cd in seeds that are hazardous to human health. The seeds of these five cultivars were further assessed for interactions between Cd and other mineral nutrient elements such as Ca, Cu, Fe, Mg, Mn and Zn. High Cd concentration in soil was found to inhibit the uptake of Mn. Furthermore, Fe and Zn accumulations were found to be enhanced in the seeds of all of the five soybean cultivars in response to high Cd concentration. Cultivar Tiefeng 31 was found to fit the criteria for a Cd-excluding cultivar under different concentrations of Cd in soils.  相似文献   
123.
我国的城市生活垃圾收运系统因其回收率低,监管难等问题,一直受到社会的广泛关注,而物联网技术因其可追溯性、动态性等特点,在解决该问题上表现出其显著优势。简要介绍了物联网技术的作用及其应用领域,总结了国内外基于物联网技术的城市生活垃圾收运情况,以我国上海市餐厨垃圾收运情况为案例,对其现状和目前存在的问题进行了总结,并结合物联网技术对餐厨垃圾信息化收运的管理方法进行了展望。  相似文献   
124.
有机食品的发展现状及趋势探讨   总被引:10,自引:0,他引:10  
介绍了有机食品的概念,分析了国际有机食品运动的发展方向、推动因素和市场潜力,预测今后几年内全球有机产品市场的年平均发展速率为15%-20%。同时,还分析了我国发展有机食品的国际环境、农业基础和发展模式,认为发展有机农业和有机食品是跨越绿色贸易壁垒的良策,国内的消费市场潜力和空间巨大,预测到2010年,我国有机食品占国内食品市场的比例可望达到1.0%-1.5%,占全球有机食品市场的份额则可望达到3.0%。  相似文献   
125.
生态小区建设中食物垃圾处理技术   总被引:1,自引:0,他引:1  
马静颖 《环境科技》2008,21(5):73-76
分析了食物垃圾的产量、特点。综述食物垃圾的常用处理方法,提出了生态小区建设中食物垃圾的合理解决方法.将食物垃圾的处理与生活污水的处理就近有机结合,为生态小区建设中废物资源化处理和利用提供有效的依据。  相似文献   
126.
秦芳  张和清 《交通环保》1999,20(5):39-40
在分析港口所属职工食堂及附近饭店的食品、餐具卫生状况及特点的基础上,根据港口及附近餐饮单位个人承包多,卫生经费投入少,食品卫生淡化的现状,对改善卫生状况提出意见和建议。  相似文献   
127.
Hydrothermal carbonization (HTC) is a thermal conversion technique that converts food wastes and associated packaging materials to a valuable, energy-rich resource. Food waste collected from local restaurants was carbonized over time at different temperatures (225, 250 and 275 °C) and solids concentrations to determine how process conditions influence carbonization product properties and composition. Experiments were also conducted to determine the influence of packaging material on food waste carbonization. Results indicate the majority of initial carbon remains integrated within the solid-phase at the solids concentrations and reaction temperatures evaluated. Initial solids concentration influences carbon distribution because of increased compound solubilization, while changes in reaction temperature imparted little change on carbon distribution. The presence of packaging materials significantly influences the energy content of the recovered solids. As the proportion of packaging materials increase, the energy content of recovered solids decreases because of the low energetic retention associated with the packaging materials. HTC results in net positive energy balances at all conditions, except at a 5% (dry wt.) solids concentration. Carbonization of food waste and associated packaging materials also results in net positive balances, but energy needs for solids post-processing are significant. Advantages associated with carbonization are not fully realized when only evaluating process energetics. A more detailed life cycle assessment is needed for a more complete comparison of processes.  相似文献   
128.
The rural economic situation in China-with a living standard mostly at subsistence level-lags far behind the prosperous development in the cities and coastal areas. To balance this disequilibrium, comprehensive concepts and endeavors are necessary keeping in view all-not just economic-interests and needs that contribute to lively rural identities. In this context the role of agriculture, where still 50% of the Chinese population are working, will be newly defined, and sustainability concepts can help to find a readjusted position within the Chinese economy focusing on environmental health and food safety as main targets of political and other supporting measures. Within the SUCCESS project, a Concept of Sustainable Agriculture was developed and it drafts one conceivable relation between the exposure to natural resources and economy and tries to find new answers to the broad range of rural challenges in China. It is a qualitative model and, therefore, not always fully applicable, but in the concrete situation of villages, it shows possible directions of sustainability-oriented development by considering the typical local potentials. In the Chinese context that means identifying the different functions of agriculture-the well-known and the hidden-to make them explicit for the Chinese public and therewith to give them new significance. The article is based on a 3-years study within the EU-China Project SUCCESS with field research in four Chinese rural communities. It analyzes the agricultural sustainability potential of these selected villages against the background of massive structural changes within the next 20 years in rural China. Starting from the current agricultural reality, based on a qualitative analysis of the actual situation, local potentials and needs towards sustainable production and marketing are identified, and possible functions of the Chinese agriculture are formulated for the future.  相似文献   
129.
重金属对食品的污染及其危害   总被引:6,自引:0,他引:6  
游勇  鞠荣 《环境》2007,(2):102-103
铅、砷、汞、镉、锡等有毒重金属通过各种途径污染食品,沿食物链进入人体后,给人体健康带来严重危害.本文综述了几种重金属对食品的污染及其来源,对人体的危害及其预防,以便提高人们的食品安全意识,加强环境保护,维护人体健康.  相似文献   
130.
A mathematical model of the individual budget of a spawning female of the copepod Acartia grani (Sars) has been used to simulate the time-scale of egg production over various external forcings (or inputs) of food fluctuation conditions. The budget matter in the body of the copepod females is distributed through four compartments: the whole digestive tract (globally named as gut), the hemolymph (which include the body fluid with available nutriments for the organs), the structural body weight, and the gonad. This small calanoid species does not carry lipid reserves but cumulate some labile reserves in its body, according to food availability. The model results show how the continuous spawning varies with food fluctuations, and suggest the mechanisms inducing the delay of response to starvation by using the metabolic reserves. Three different patterns in egg production response are observed: food fluctuations with frequencies below 12 h have no effect on egg production; food fluctuations of 12 h to 5 days induce synchronous egg production fluctuations; beyond 5 days the strong physiological changes induced by long starvation durations create delays in the responses to food replenishment. The available data of cultivated cohorts under laboratory conditions are used to validate the model. The properties underlined by the model, in particular its weak capacity to respond to starvation, allow explaining A. grani distribution in specific habitats. Different experimental protocols for complementary experiments are proposed to complete the model validation in other forcing conditions.  相似文献   
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