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761.
762.
河南省甘薯产业化发展对策研究 总被引:1,自引:0,他引:1
甘薯高产稳产、抗逆性强、营养丰富又有保健功能,是入世后中国农产品参与国际竞争的强势作物。通过对河南省甘薯的生产现状与优势进行分析,针对生产中存在的主要问题,提出了河南省甘薯产业化发展的对策和建议。 相似文献
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766.
发制品行业是以人发、人造纤维等为原材料进行假发加工的行业。许昌市发制品的生产过程大致可分为两个阶段:漂染和前后处理。漂染过程用水量大,产生的废水难以处理。其中过酸、氧化、染色配置的溶液使用一次后直接排放,不符合清洁生产要求,且所排放的溶液可考虑中和多次利用。漂染过程水资源消耗量大,废水产生量大,没有考虑废水综合利用。按清洁生产的要求在以上环节可通过技术革新和设备改造得以改进。 相似文献
767.
吉向新 《中国环境管理干部学院学报》2010,20(1):19-21,26
由于对生态建设的艰巨性和长期性、资金需求、阻力估计不足,生态建设过于口号化,我国生态建设存在诸多问题。从环境承载力的定义入手,分析了生态建设与环境承载力的关系,提出了当前生态建设应采取发展生态农业、生态工业、生态旅游、倡导绿色消费、加强污染综合治理等措施。 相似文献
768.
Handong Yang 《Environmental pollution (Barking, Essex : 1987)》2010,158(7):2504-2510
A 5.3 m sediment core and soil samples were taken from Diss Mere and its catchment. The sediment core was dated and Hg analysed on the sediment and soil samples. The Hg record of the sediment core shows that Diss Mere has been contaminated for the past thousand years and the historical trends in sediment contamination are in good agreement with the development of the weaving industry in Diss and hemp cultivation in the region. Mercury contamination in Diss Mere has been significant and reached a peak in the mid-19th century with sediment Hg concentrations over 50 μg g−1. Elevated Hg concentrations were also found in contemporary soils in residential areas with former industrial land use. Although local hemp cultivation and the traditional weaving industry were abandoned a hundred years ago, Hg contamination caused by these activities still exists in the catchment, and affects the lake. 相似文献
769.
Heavy metal removal and cyanide destruction in the metal plating industry: an integrated approach from egypt 总被引:1,自引:0,他引:1
Wastewater produced from a metal plating is a major environmental problem. Industrial auditing revealed that the main source
of pollution mainly originated from rinsing water. The characterization of final effluent showed that it is highly contaminated
with hazardous heavy metals and cyanide. The concentration of copper, hexavalent chromium, nickel, and cyanide in the rinsing
water of metal plating department was 14.8, 40.9, 13.3, and 19 mg/l, respectively. The concentration of cyanide and zinc from
the galvanizing department reached 60 and 80 mg/l. The remediation scheme included the application of in-plant control measures
via changing the rinsing process followed by the destruction of cyanide and reduction of hexavalent chromium bearing wastes.
The pretreated wastes were then mixed with other industrial wastes prior to a combined chemical coagulation-sedimentation
using lime and/or lime in combination with ferric chloride. The results indicated that, after applying the waste minimization
measures alone at the source, prior to final treatment of industrial waste, removal rates of cyanide, copper, nickel, and
chromium concentrations were 23.2%, 14.9%, 32.3%, and 55.3%, respectively in the rinse water from metal plating department.
Furthermore, the removal rates of cyanide and zinc in the galvanizing department reached 59.7% and 24.3. The integrated control
measures and treatment scheme led to more than 99% removal of copper, nickel, chromium, and zinc, while the complete removal
of cyanide was achieved in the final effluent. 相似文献
770.
De Silva Sena S. Turchini Giovanni M. 《Journal of Agricultural and Environmental Ethics》2008,21(5):459-467
The status of wild capture fisheries has induced many fisheries and conservation scientists to express concerns about the
concept of using forage fish after reduction to fishmeal and fish oil, as feed for farmed animals, particularly in aquaculture.
However, a very large quantity of forage fish is being also used untransformed (fresh or frozen) globally for other purposes,
such as the pet food industry. So far, no attempts have been made to estimate this quantum, and have been omitted in previous
fishmeal and fish oil exploitation surveys. On the basis of recently released data on the Australian importation of fresh
or frozen fish for the canned cat food industry, here we show that the estimated amount of raw fishery products directly utilized
by the cat food industry equates to 2.48 million metric tonnes per year. This estimate, plus the previously reported global
fishmeal consumption for the production of dry pet food suggest that 13.5% of the total 39.0 million tonnes of wild caught
forage fish is used for purposes other than human food production. This study attempts to bring forth information on the direct
use of fresh or frozen forage fish in the pet food sector that appears to have received little attention to this date and
that needs to be considered in the global debate on the ethical nature of current practices on the use of forage fish, a limited
biological resource. 相似文献