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101.
The mountains hold the key to global ecological and social stability by virtue of being centres of biological and cultural diversity and the storehouse for water and other resources. However, they are becoming unable to sustain the demands of the changing life style of the growing number of inhabitants as well as the population in the plains and, therefore, the resources are depleting rapidly. Inadequacy of research and development (R&D) projects undertaken in mountain ecosystems is, perhaps, a major factor that has not enabled us to evolve and introduce suitable interventions to replenish and restore the health of the degraded mountains. In this article, taking the Indian Himalayan region as a case study, an effort has been made to understand the adequacy and appropriateness of R&D projects in mountain ecosystems by analysing the research and development projects implemented in this region from 1985–86 to1998–99. The analysis revealed inadequacy in the number and budgets of R&D projects implemented in this mountain ecosystem as a whole as well as in specific subject areas; the number of R&D projects implemented during this period was only 5.28% of the total projects, with a fund allocation of 4.45% of the total R&D budget of India, which appears to be inadequate considering the geophysical and bio-social importance of the Himalaya. The finding suggests that national funding agencies of mountain nations need to increase the number of R&D projects in mountain regions as a priority, with the intention of developing scientific packages capable of restoring the degraded ecosystem of the mountains and ensuring their sustainable development.  相似文献   
102.
Three strains of halophilic bioemulsifier-producing bacteria; Bacillus sp. 2BSG-PDA-16, Bacillus sp. DV2-37 and Bacillus licheniformis ABRII6 were isolated from crude oil polluted water samples. Characteristics of exopolymers produced by these strains in media supplemented with various hydrocarbons instead of glucose were studied. Yield production, chemical composition, emulsifying, rheological and flocculating properties of exopolymers varied according to the strain and the carbon source. The highest amount of exopolymers synthesized by Bacillus sp. 2BSG-PDA-16, Bacillus sp. DV2-37 and B. licheniformis ABRII6 was 11, 18.5 and 12.4 g/l, respectively from media amended with glucose, while the most active emulsifiers were those obtained from media added with crude oil. Furthermore, all exopolymers produced were capable of emulsifying crude oil more efficiently than the three chemical surfactants tested as control (Tween 20, Tween 80 and Triton X-100). Respect to chemical composition, exopolymers produced on hydrocarbons always have lower content of carbohydrates and proteins than exopolymers produced in medium amended with glucose, however they showed higher amounts of uronic acids, sulfates and acetyl residues. The rheological study suggested that the exopolymers have characteristics of the pseudoplastic fluids. Efficiency of bacterial strains to remove PAH seems to agree with their potential applicability in oil bioremediation technology.  相似文献   
103.
104.
Optimal biogas production and sludge treatment were studied by co-digestion experiments and modeling using five different wastewater sludges generated from paper, chemical, petrochemical, automobile, and food processing industries situated in Ulsan Industrial Complex, Ulsan, South Korea. The biomethane production potential test was conducted in simplex-centroid mixture design, fitted to regression equation, and some optimal co-digestion scenarios were given by combined desirability function based multi-objective optimization technique for both methane yield and the quantity of sludge digested. The co-digestion model incorporating main and interaction effects among sludges were utilized to predict the maximum possible methane yield. The optimization routine for methane production with different industrial sludges in batches were repeated with the left-over sludge of earlier cycle, till all sludges have been completely treated. Among the possible scenarios, a maximum methane yield of 1161.53 m3 is anticipated in three batches followed by 1130.33 m3 and 1045.65 m3 in five and two batches, respectively. This study shows a scientific approach to find a practical solution to utilize diverse industrial sludges in both treatment and biogas production perspectives.  相似文献   
105.
There is a lack of information concerning human health risks due to exposure to mercury contained in shark fins, through dietary intake. Health risk assessment of shark fins, collected from 5 cities in China: Hong Kong (HK), Beijing, Shanghai (SH), Haikou (HN) and Wenzhou (WZ), was conducted, based on total mercury and methylmercury, and analyzed by a cold vapor atomic fluorescence spectrometry equipped with high-performance liquid chromatography, respectively. The results showed that 16.8 % samples from HK, 8.3 % from SH, 33.3 % from HN, and 16.8 % from WZ were regarded as unsafe for human consumption. Extremely high consumption rates of shark fins for an adult and a child (0.150 and 0.0807 kg/day, respectively), at 95th centile, samples from WZ demonstrated high non-cancer risks (adverse health effects) (Hazard Quotient = 16.0) on adults (aged 25–65), and samples from SH, HN and WZ also showed high non-cancer risks (Hazard Quotient = 12.9, 21.0, and 34.4, respectively) on children (aged 1–7). Consumption of shark fins may be detrimental to human health.  相似文献   
106.
107.
采用PDA、NA以及高氏一号培养基,分别从毛白杨、绦柳、荻以及二穗短柄草植株内分离、纯化出37株内生菌,其中34株为细菌,3株为放线菌.以分离纯化得到菌株各自对应的营养培养基并添加不同浓度的污染物对获得的37株内生菌进行污染物的耐受筛选,发现24株分别对20 mg·L-1的aroclor1254和BDE209具有一定的耐受性.利用无机盐培养基并添加污染物作为微生物唯一碳源筛选,发现菌株CPY-4和菌株SGL-1可以在只提供4-BDE的无机盐培养基中存活,菌株CPY-4,SGL-1、菌株4、菌株13可以在提供BDE209和aroclor1254的无机盐培养基中存活.形态学观察和16Sr DNA序列同源性分析,初步确定菌株SGL-1为克雷伯氏菌属,菌株CPY-4为地衣芽胞杆菌,菌株4和菌株13为肠杆菌属.  相似文献   
108.
Volatile organic compounds (VOCs) are crucial to control air pollution in major Chinese cities since VOCs are the dominant factor influencing ambient ozone level, and also an important precursor of secondary organic aerosols. Vehicular evaporative emissions have become a major and growing source of VOC emissions in China. This study consists of lab tests, technology evaluation, emissions modeling, policy projections and cost-benefit analysis to draw a roadmap for China for controlling vehicular evaporative emissions. The analysis suggests that evaporative VOC emissions from China's light-duty gasoline vehicles were approximately 185,000 ton in 2010 and would peak at 1,200,000 ton in 2040 without control. The current control strategy implemented in China, as shown in business as usual (BAU) scenario, will barely reduce the long-term growth in emissions. Even if Stage II gasoline station vapor control policies were extended national wide (BAU + extended Stage II), there would still be over 400,000 ton fuel loss in 2050. In contrast, the implementation of on-board refueling vapor recovery (ORVR) on new cars could reduce 97.5% of evaporative VOCs by 2050 (BAU + ORVR/BAU + delayed ORVR). According to the results, a combined Stage II and ORVR program is a comprehensive solution that provides both short-term and long-term benefits. The net cost to achieve the optimal total evaporative VOC control is approximately 62 billion CNY in 2025 and 149 billion CNY in 2050.  相似文献   
109.
在全球节能减排的宏观政策之下,我国洗涤行业的逐步发展与壮大应符合国家节能减排的整体方向和目标,加强节能减排意识,实施有关节能减排的措施,走可持续发展的道路.本文通过对国外发达国家洗涤行业节能减排的政策、方法和经验的了解和学习,结合我国洗涤行业的实际特点,旨在找到适合我国洗涤行业的可持续发展道路.研究表明,虽然我国洗涤行业还处于快速扩大发展的初期,但我国可以根据自身的具体情况有选择性地借鉴国外发展和节能减排的经验和方法,在此基础上,结合具体实际特点,开拓创新,开发出适合我国洗涤行业的可持续发展道路,在快速扩大发展的同时,与其他行业和领域一同为实现我国的节能减排目标而努力.  相似文献   
110.
三峡库区库中干流及支流水体夏季二氧化碳分压及扩散通量   总被引:16,自引:10,他引:6  
以三峡库区库中干流以及主要支流——梅溪河为研究区,于2013年5月对该区域水体中溶解二氧化碳分压(pCO2)进行了走航观测.结果表明,夏季梅溪河表层pCO2为6.8~7.5 Pa,三峡库区库中长江干流表层pCO2为201.4~210.2 Pa.在库区干、支流交汇的过渡区水体剖面上,表层水体pCO2最低为53.5 Pa,随着水深增加,pCO2急剧增大,在3 m处达到约210Pa后基本保持不变.通过计算,库区支流梅溪河和库区干流表层水体的CO2释放通量分别为-7.48 mmol·(m2·d)-1和39.58 mmol·(m2·d)-1.结果表明,库区支流梅溪河表现为大气中CO2的"汇",而库区干流表现为CO2的"源",库区干、支流水体在CO2的释放上有显著差异.  相似文献   
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