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231.
For prevention and treatment of Kaschin-Beck disease by applying Se fertilizer to soil to increase Se up to normal level for the wheat grains is introduced in this paper. After use this measure the intake of Se by the residents in the exemplary area increased from 10.4μg to 33.6 μg per day in average. After supplementing Se to human body one year, there is no new patient found among 300 healthy children in the exemplary area but 4 patients found among 264 healthy children in the control area. It is shown that by applying Se fertilizer to KBD area is a effective way for preventing and cure this disease.  相似文献   
232.
水质污染总量的合理分配研究   总被引:1,自引:0,他引:1  
水质污染总量削减分配的目的应该是实现各种资源的合理组合和高效利用.本文利用运筹学中的DEA方法,对企业的经济、管理及排污三个方面的素质进行了评价,进而形成企业素质综合指数.企业素质综合指数为我们确定总量控制对象和总量削减分配权重提供了必要的依据.  相似文献   
233.
Water pollution from the pulp and paper industry is one of the most serious environment problems in China. In order to prevent and treat pollution of the pulp and paper industry, the following works have been done in recent years: 1. Making necessary policies, measures and regulations; 2. Making overall planning and rational layout; 3. Relying mainly on internal treatment developing external treatment as supplement; 4. Improving the technology of treating wastewater of the pulp and paper industry.  相似文献   
234.
Before 1970s the Second Songhua River and Ji Canal of China had been polluted seriously by mercury. During peak pollution period, mercury levels in water, sediment and fish body of these rivers were close to or even higher than that of famous Minamata Bay of Japan. Some residents who live near to the polluted rivers were affected and the methyl mercury values in their blood, hair and urine were higher than normal people obviously . Since the fish had decreased even vanished in these rivers, so the food chain that transfers mercury to human also was out off almostly. However, nervous symptoms of Minamata disease were discovered among fisherman who had eaten more fishes. This report relates the stories about the mercury pollution of the Second Songhua River and Ji Canal.  相似文献   
235.
Effects of cycling and constant temperature on development and reproduction of the armyworm, Mythimna separata (Walker) were investigated by rearing the insects on the artificial diet under temperatures covering low(16-24℃ vs. 20 ℃ ), medial(20-28℃ vs. 24℃ ) and high(24-32 ℃ vs. 28 ℃) regions. In the low region, all the immature stages of the insect developed significantly faster under alternating temperatures than at corresponding constant temperatures. For the medial region, their development was little affected by variable temperatures. For the high region, developmental durations tended to be longer under cycling temperatures except egg stage.Mean fecundities of the adult moths markedly increased under cycling temperatures as compared with those at respective constant temperature in all regions.Possible reasons for effect of alternating temperatures on insect development are discussed in some details.  相似文献   
236.
Species analysis methods for hydrolysis polymerization of aluminum   总被引:2,自引:0,他引:2  
SpeciesanalysismethodsforhydrolysispolymerizationofaluminumFengLi,LuanZhaokun,TangHongxiaoResearchCenterforEcoEnvironmenta...  相似文献   
237.
China’senvironmentalscientificresearchandtechnologydevelopment:reviewandenvisageLiuJianBureauofS&TforResourcesandEnvironment,...  相似文献   
238.
1IntroductionLandcoverchangehasanincreasingimpactonforestecosystemsworldwide.Thedestructionofnativehabitatsisrecognizedasoneo...  相似文献   
239.
The synchronous fluorescence spectroscopy of three polymiclear aromatic hydrocarbons was studied. It was shown that the specific Δλ of the spectra were 10nm for benzo(k) fluoranthene, 25 nm for benzo(a) pyrene, and 40 nm for pyrene. The peaks of the spectra were at 407, 404, and 373 nm for the three chemicals, respectively. Benzo(k) fluoranthene, benzo(a) pyrene, and pyrene in the urine samples from smokers were identified by high pressure liquid chromatography combined with the synchronous fluorescence spectroscopy.  相似文献   
240.
On Peak Namjagbarwa (Tibet Plateau), Lushan Mountain (Province Jiangxi), Flower Mountain and Shangdianzi (Beijing, near Great Wall) aerosol samples have been collected by cascade samplers. For comparison aerosol samples from Beijing City, Pacific Ocean and South Pole also have been collected. Samples were analyzed with PIXE or XFA instruments. Factor analysis and enrichment factor calculation were performed to process the data.  相似文献   
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