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1.
讨论分析了我国野生动物资源现状和《野生动物保护法》制订的历程、实质及贯彻实例的措施。  相似文献   
2.
复杂人——机系统中的人因失误   总被引:26,自引:12,他引:26  
随着人——机系统变得越来越多,装置的可靠性越来越高,人因失误已成为重要的潜在事故源。本文描述了复杂人——机系统的特征,探讨了该系统中人因失误的定义、分类、数据采集和事故模型。这些研究有助于对人因失误的预测、预防和减少。  相似文献   
3.
用缺氧生物滤池与UASB相串联的工艺对杭州市天子岭垃圾填埋场惨滤液进行了中试试验。通过实验,总结了缺氧生物滤池的挂膜特性及UASB起动的成功经验。最终的试验结果表明:出水COD、BOD、SS分别稳定在900mg/L、150mg/L、250mg/L以下,缺氧生物滤池对渗滤液具有很好的预处理效果,不仅能脱吸部分NH3、CO2、H2S,而且能提高它的可生化性,为UASB的高效运行创造了良好的条件。  相似文献   
4.
应用灰色系统理论,根据江苏省地震工程研究院的地震科技开发资料,分别以项目负责人的年龄、学历、职称、职务、学科作为比较数列,对年度内完成的实际合同额进行了多因素灰色关联分析,排出了关联序。研究结果客观地揭示了开发能力与人的各种因素——年龄、学历、职称、职务、学科之间的相互关系,为市场经济条件下,地震科技人才的开发、培养和应用,提供了科学依据。  相似文献   
5.
To characterize Streptomyces isolated from cattle feces for converting lignocellulose into reducing sugars, five Streptomyces strains were screened. All the strains could convert lignocellulose into reducing sugars. The strain A16 accumulate 3.3-folds more reducing sugars on cottonseed shells treated with ethanol than without the treatment (P?<?0.05). The five strains did not accumulate more reducing sugars on rice straws and wheat brans than those on cottonseed shells. Compared with A10 alone, the microbial combination of F1 + A10 accumulated 19, 61, and 25 % less reducing sugars on cottonseed shell, rice straw, and wheat bran than those by A10 solely, respectively (P?<?0.05). Further studies indicated that the activities of avicelase and xylanase were not correlated with the reducing sugar amount accumulated by the test strains. Strain A7 could produce more cellular lipids with xylose and glucose as the sole carbon sources. This study shows the potential for Streptomyces strains from herbivore feces to convert lignocelluloses into lipids and reducing sugars for fuel production.  相似文献   
6.
采用滤纸片法和混合法对野外环境生长的薰衣草精油的抑菌作用进行了研究,并对两种试验方法进行了比较,测定了最小抑菌浓度(MIC)与最小杀菌浓度(MBC),以期充分发挥薰衣草精油的抑菌作用.滤纸片法结果表明:薰衣草精油对多数实验菌都有抑菌作用,对枯草杆菌则未表现出抑制作用;混合法实验显示:薰衣草精油对实验菌均有抑菌作用,精油浓度与抑菌作用成线性相关,抑菌作用较滤纸片法效果更好.在使用时,可用于表面喷涂、熏蒸,还可将精油作为安全的食品添加剂,提高食品的保鲜效果,保证其品质.  相似文献   
7.
To investigate the variation of Zn and Cd accumulation and tolerance of Sedum alfredii (a newly reported Zn/Cd hyperaccumulator), field surveys and hydroponic experiments were conducted among three populations of this species: two originating from old Pb/Zn mines in Zhejiang (ZJ) and Hunan (HN) Provinces and one from a "clean" site in Guangdong (GD) Province, China. Under field conditions, up to 12,524 and 12,253 mg kg(-1) Zn, and 1400 and 97 mg kg(-1) Cd in shoots of ZJ and HN plants were recorded respectively. Under hydroponic conditions, ZJ and HN plants accumulated significantly higher Zn and Cd in their leaves and stems, and possessed significantly higher Zn and Cd tolerance than GD plants. Among the two contaminated populations, ZJ plants showed higher Cd tolerance and accumulation (in leaves) than HN plants. The present results indicate that significant differences in Zn and Cd accumulation and tolerance exist in populations of S. alfredii.  相似文献   
8.
三种偶氮染料降解历程在紫外-可见光谱上的表现   总被引:20,自引:2,他引:18  
吴峰  华河林  邓南圣 《环境化学》2000,19(4):348-351
本文对基本结构相似的三种偶氮染料橙黄Ⅱ、活性艳红X-3B和活性黑K-BR水溶液在铁粉还原-光氧化两步法处理中的紫外-可见光谱图作对比分析,依据其结构与特征吸收的关系,初步推测还原铁粉-光氧化法降解染料的历程。  相似文献   
9.
Fluorine or fluoride can have toxic effects on bone tissue and soft tissue at high concentrations. These negative effects include but not limited to cytotoxicity, immunotoxicity, blood toxicity, and oxidative damage. Apoptosis plays an important role in fluoride-induced toxicity of kidney, liver, spleen, thymus, bursa of Fabricius, cecal tonsil, and cultured cells. Here, apoptosis activated by high level of fluoride has been systematically reviewed, focusing on three pathways: mitochondrion-mediated, endoplasmic reticulum (ER) stress-mediated, and death receptor-mediated pathways. However, very limited reports are focused on the death receptor-mediated apoptosis pathways in the fluoride-induced apoptosis. Therefore, understanding and discovery of more pathways and molecular mechanisms of fluoride-induced apoptosis may contribute to designing measures for preventing fluoride toxicity.  相似文献   
10.

Purpose

Feathers are one of the most abundant bioresources. They are discarded as waste in most cases and could cause environmental pollution. On the other hand, keratin constituted by amino acids is the main component of feathers. In this article, we reported on biorefined feathers and integrants and application of degraded products.

Materials and methods

The fermentation of whole chicken feathers with Stenotrophomonas maltophilia DHHJ in a scale-up of a 5-L bioreactor was investigated in this article. The fermentation process was controlled at 0.08 MPa pressure, 2.5 L/min airflow, and 300 rpm as 100% oxygen saturation level, 40°C, and pH 7.8.

Results

Feathers were almost completely degraded in the tested fermentation reaction with the following conditions: 80 g of whole feathers in 3 L fermentation broth for 72 h, seed age of 16 h, 100 mL inoculation amount, and 50% oxygen saturation level. The degraded products contain 397.1 mg/L soluble protein that has mass weight ranging from 10 to 160 kD, 336.9 mg/L amino acids, and many kinds of metal ions. The fermentation broth was evaluated as leaf fertilizer and found to increase plant growth to 82% or 66% for two- or fourfold dilutions, respectively. In addition, in a hair care assay, the broth showed a hair protective function by increasing weight, flexibility, and strength of the treated hair.

Conclusions

The whole feathers were degraded completely by S. maltophilia DHHJ. The degraded product includes many factors to life, such as peptides, amino acids, and mineral elements. It could be applied as leaf fertilizer and hair care product.  相似文献   
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