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961.
自然选育酵母菌对不同废水处理及资源化研究   总被引:7,自引:0,他引:7  
从色拉油加工废水,味精废水、印染废水、钻井废水等4种特性各异的废水中筛选出酵母菌,并根据形态特征和生理生化特征对筛选到的12种酵母菌(包括2种耐氨酵母)进行了鉴定。结果表明:酵母菌处理工艺对色拉油加工废水和味精废水这两类高浓度有机废水具有较好的处理效率,如前者的TOC和后者的COD的去除率均在85%以上。但对人工合成物质含量较高的印染废水和钻井废水处理效果较差。这一结果可能与酵母菌原来所处的环境条件有关。  相似文献   
962.
The City of Austin, Texas, is one of the fastest growing metropolitan areas in the United States. It is also in one of the most biologically diverse terrestrial ecosystems in the world: the Balcones Canyonlands. Five cave invertebrates and two species of birds that inhabit the area are listed as threatened or endangered, two species of plants are candidates for listing, several others are considered rare and of concern, and a species of the salamander has also been proposed for listing. A habitat conservation plan, of national significance according to Secretary of Interior Bruce Babbit (Haurwitz 1996), has been under development for the last several years to conserve those endangered species through a 2400-ha system of preserves and to allow development to continue in more than 162,000 ha of surrounding area. The preserve system, comprising several units ranging in size from less than a hundred to several thousand hectares, would be bordered in many instances by developed areas. Development and maintenance of the infrastructure necessary for new and existing development, both commercial and residential, could have negated the biological value of the preserves (e.g., power-line corridors, water-treatment pipelines and facilities). The challenge of bringing this plan to fruition illustrates the complex biological, technical, and sociological context within which habitat conservation planning may occur. Resolving resource use conflicts of this nature have several commonalities that overarch these contexts. If recognized and addressed, one may move easily and foster positive results. These commonalities can be expressed as principles such as: relying on scientists to recognize, but not solve problems; acting before a scientific consensus is achieved; including human motivation and responses as part of the system to be studied and managed; and confronting uncertainty.  相似文献   
963.
Single-species listings under provisions of the federal Endangered Species Act (ESA) have caused, or have been accused of causing, significant regional economic impact. In an attempt to avoid such adverse effects on regional economic development, the state of California passed the Natural Communities Conservation Planning Act (NCCP) in 1991. It is a voluntary, consensus-based approach to balancing protection of sensitive biota and biodiversity with regional economic development. The pilot NCCP program for the conservation of several threatened, endangered, and category 1 species, plus an additional 35 coastal sage scrub-related species in southern California, was completed and submitted to the public for review and comment in December 1995. This program proposes the voluntary establishment of a 86,600-ha multispecies reserve system. Once completed, participating landowners will receive ESA Section 10(a) incidental take permits for present and identified future projects. Utility rights-of-way are incorporated into the program as important connective linkages between reserve units and other adjacent important habitat areas. All data and information regarding the proposed results of the NCCP are subject to change pending agency response to public comments on the draft Habitat Conservation Plan and joint EIR/EIS.  相似文献   
964.
研究离子色谱(IC)与石墨炉原子吸收光谱(GFAAS)联用测定水体中铁形态的方法。用Shim-pack阳离子交换柱分离Fe(Ⅲ)和Fe(Ⅱ),用石墨炉原子吸收法检测,Fe(Ⅱ)和Fe(Ⅲ)的检出限分别为3.8ng/ml和7.7ng/ml。本方法已用于检测自来水和河水的铁的价态,取得了令人满意的结果。  相似文献   
965.
甘肃省悬钩子属植物资源分布及其开发前景初探   总被引:8,自引:0,他引:8  
悬钩子属植物在甘肃共有34种、8变种,分布于南秦岭山地、北秦岭山地森林、甘南山地森林、东祁连山林区、陇西、陇东黄土高原区及甘南高山草原区。大多数具可食性,具开发利用价值。建立悬钩子的栽培试验基地是保证原料供应的重要措施。通过对悬钩子产品的市场需求量及产品属类的评估,可望将其潜在的野生价值转变为实际生产力。  相似文献   
966.
结合桐柏县的实例,对县域生态功能区划分的原则和方法进行初步探讨。综合利用3S技术对县域生态敏感性和生态服务功能重要性的分析和评价,提出桐柏县生态服务功能区划的初步方案。将桐柏县划分为生态支持区,产品供给区,生态调节区。简要分析了各功能区在桐柏县经济可持续发展中的地位和作用,指出各区协调发展的方向和途征。  相似文献   
967.
电子去离子净水技术   总被引:1,自引:0,他引:1  
概述了EDI净水技术的发展历程、原理、组件型式与性能  相似文献   
968.
Irradiation of carboxin (1) with a 500 W UV lamp (filter Pyrex) in CH3CN leads to the products 3, 5-8, 12-14 depending upon the reaction conditions. All photo-products were isolated and characterized. Photooxidation occurred even if unsensitized, while photoalteration was very slow in the absence of oxygen. The main oxygenated-products 3 and 13 were also recovered under biomimetic conditions by exposure of an aqueous solution of 1 to sunlight.  相似文献   
969.
外来入侵物种空心莲子草光合日变化初步研究   总被引:2,自引:0,他引:2  
外来入侵物种空心莲子草(Alternanthera philoxeroides)发生广、危害重的区域多为中国南方省市,2005年发现其已大面积入侵山东省济南市境内的小清河上游.测定了空心莲子草净光合速率、气孔导度和细胞间隙CO2浓度,并与同一生境的芦苇(Phragmites communis)和水芹(Oenanthe javanica)进行了比较.空心莲子草净光合速率日变化曲线为双峰型,最高峰值24.40μmol CO2/(m2·s)出现在10:00左右,第二峰值22.80 μmol CO2/(m2·s)出现在16:00左右,整个曲线明显高于对照植物芦苇和水芹.在16:00至16:30光强迅速下降阶段.其净光合速率仍能保持较高水平,为9.85 μmol CO2/(m2·s).  相似文献   
970.
Numerous organic compounds have been analyzed by coupled gas chromatography-mass spectroscopy (GC-MS) in flue gas after fluid bed combustion of four coal species from South Africa, Poland, Spitsbergen and Ruhr area (Germany). Polynuclear aromatic hydrocarbons, aliphatic hydrocarbons, chlorinated, heterocyclic and nitro compounds as well as phthalate esters are detected.  相似文献   
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