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1.
本发明采用花生作原料,经物理方法处理,再经生物酶工程提取花生的有效成分———双岐因子,然后将双岐因子按比例加入奶粉、蔗糖、香精和水,经水溶解,搅拌,冷却,装瓶,形成规模化生产。花生双岐杆菌饮料对增强人体免疫、防病、抗衰老及抗肿瘤方面具有很好的作用。(CN1224...  相似文献   

2.
废钻井液污染分析及处理方法的探讨   总被引:7,自引:2,他引:5  
为解决废钻井液对周围环境的污染,介绍了废钻井液的成分及对环境的影响,分析了国内外废钻井液处理方法的优缺点,详细阐述了中原油田结合本单位情况,用无害化处理技术处理废钻井液的方法和效果。试验表明:无害化处理剂中的各组分与废钻井液中各污染因子发生化学和物理作用,经3~5个月固化后可以达到无害化处理的目的。分析认为:中原油田钻井废弃物无害化处理技术是切实可行的。  相似文献   

3.
陈泽民 《四川环境》1990,9(2):46-52
传统的生化处理印染废水的脱色效果很不理想,但本试验通过对已驯化的活性污泥脱色有效菌株进行诱变、筛选、培养和优化,使生化法处理印染废水的脱色效果得到明显的提高。  相似文献   

4.
<正> 微生物处理在有害废物处理领域中有着广阔的应用前景,它提供了一个廉价、有效的清除方法,对污染物所进行的是最终的清除。从微生物学原理出发,已经有很多混合培养系统和一系列新的培养法适用于处理有害物。多数情况下,生物处理最有利于与其它技术结合使用,如热力学去除或物理、化学预处理。许多已被封存的有害废物可用微生物来处理。微生物处理是多方面的,处理系统所用的微生物可回收利用。污染物去除的结果已表明,用可靠的工程原理是适宜的,各种生物处理方法所获得的经验越来  相似文献   

5.
对固体废物有毒有害物质进行处理或处置的方法有掩埋法、焚烧法及高温热解、溶剂洗涤等方法。文中介绍了一种化学处理方法,在脱水、固化、稳定、中和、钝化的系统处理过程中,同时交叉进行物理、化学和热分解反应。利用这种方法处理含油及碳氢化合物污泥,能降低碳氢化合物废物中有毒有害成分的含量,使其毒性、危险性得到有效控制。该方法主要应用于石油化工、油田开发工业、煤加工工业、冶金工业等领域。  相似文献   

6.
随着电子废弃物数量的日益增加和对电子废弃物资源化利用要求的提高,电子废弃物经历了由堆存到资源化利用的发展过程.目前电子废弃物资源化技术主要包括物理处理法、化学处理法和热处理法等方法,实现电子废弃物的资源化.  相似文献   

7.
生物炭因其具有含碳量高、孔隙发达、官能团丰富等特点,被广泛应用于改良土壤、增加碳汇、修复环境污染等农业和环境保护领域。近年来,研究发现利用物理、化学或生物方法对生物炭进行改性处理制备具有新性能、新结构的功能性生物炭材料,可以显著提高其吸附能力。本文综述了制备功能性生物炭常用的化学改性处理方法,阐述了功能性生物炭与土壤重金属之间可能存在相互作用机制及功能性生物炭在土壤重金属污染修复中的应用,对功能性生物炭在土壤重金属污染领域今后的研究方向做出了展望。  相似文献   

8.
福建省旅游产业影响因素的灰色关联分析   总被引:2,自引:0,他引:2  
当前,灰色关联度已广泛应用于不同领域内相关因子的分析与预测.借助该法分析和比较了1997-2001年和2002-2006年两个时间段内影响福建省旅游业发展的内外因子.研究结果表明,福建省的旅游业在很大程度上受制于经济发展水平、交通可达性、产业化水平、旅游品牌等因素.建议福建省通过加快旅游支撑体系建设,实行集群式发展战略,培育和壮大海峡旅游品牌来实现旅游业的快速发展.  相似文献   

9.
铬渣的危害与解毒技术   总被引:1,自引:0,他引:1  
本文介绍了铬渣的产生过程和主要成分,以及我国铬渣的产生和污染现状;介绍了化学处理法、物理/化学法、熔烧法和固化/稳定化处理法等铬渣解毒技术原理;概括了目前国内主要的铬渣综合利用方式.  相似文献   

10.
贾滨洋  刘宜 《四川环境》2008,27(1):81-86
人工湿地法处理废水的技术是目前国际污水处理研究领域的热点,该方法利用生态系统中物质循环的原理,使用生物方法去除污染物质.本文对人工湿地处理污水的机理研究现状进行了总结,并讨论了人工湿地处理污水应用的适应性.  相似文献   

11.
Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.  相似文献   

12.
ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m2) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft3/sec (0.085 to 3.34 m3/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.  相似文献   

13.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

14.
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.  相似文献   

15.
In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.  相似文献   

16.
Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.  相似文献   

17.
Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.  相似文献   

18.
The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.  相似文献   

19.
Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.  相似文献   

20.
The SPARROW (SPAtially Referenced Regression on Watershed attributes) model was used to simulate annual phosphorus loads and concentrations in unmonitored stream reaches in California, U.S., and portions of Nevada and Oregon. The model was calibrated using de‐trended streamflow and phosphorus concentration data at 80 locations. The model explained 91% of the variability in loads and 51% of the variability in yields for a base year of 2002. Point sources, geological background, and cultivated land were significant sources. Variables used to explain delivery of phosphorus from land to water were precipitation and soil clay content. Aquatic loss of phosphorus was significant in streams of all sizes, with the greatest decay predicted in small‐ and intermediate‐sized streams. Geological sources, including volcanic rocks and shales, were the principal control on concentrations and loads in many regions. Some localized formations such as the Monterey shale of southern California are important sources of phosphorus and may contribute to elevated stream concentrations. Many of the larger point source facilities were located in downstream areas, near the ocean, and do not affect inland streams except for a few locations. Large areas of cultivated land result in phosphorus load increases, but do not necessarily increase the loads above those of geological background in some cases because of local hydrology, which limits the potential of phosphorus transport from land to streams.  相似文献   

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