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981.
介绍了隆回县金银花资源培育和加工利用现状,综合分析了金银花的综合价值和发展前景,针对当前金银花产业发展中存在的经营方式落后、加工粗放、销售不畅等问题,提出了金银花产业发展的对策. 相似文献
982.
Zhengyan Li Mark Gibson Chang Liu Hong Hu 《Environmental monitoring and assessment》2013,185(6):5221-5230
Nonylphenol is an endocrine disruptor with harmful effects including feminization and carcinogenesis on various organisms. This study aims to investigate the distribution and ecological risks of nonylphenol in the Daliao River Estuary, China. Nonylphenol, together with other phenolic endocrine disruptors (bisphenol A, 4-t-butylphenol, 4-t-octylphenol, and 2,4-dichlorophenol), was detected in surface water and sediment on three cruises in May 2009, June 2010, and August 2010, respectively. A large flooding occurred during our sampling campaign in August and its effect on nonylphenol concentrations and fluxes in the estuary was therefore evaluated. The results showed that nonylphenol with a concentration range between 83.6–777 ng l?1 and 1.5–456 ng?g?1 dw in surface water and sediment was the most abundant among the phenolic compounds, accounting for 59.1–81.0 and 79.9–92.1 % of the total phenolic concentration in surface water and sediment, respectively. The concentrations recorded in May and June were comparable, whereas those in August were considerably higher, mainly due to the flush of flooding. The flooding also caused a 50 times increase in nonylphenol flux from the estuary into the adjacent Bohai Sea. Nonylphenol concentrations in the estuary have exceeded the threshold level of undesirable effects with a potential risk of harm to local species, especially benthic organisms. 相似文献
983.
It is significant to design best management practices (BMPs) and determine the proper BMPs placement for the purpose that
can not only satisfy the water quantity and water quality standard, but also lower the total cost of BMPs. The spatial rainfall
variability can have much effect on its relative runoff and non-point source pollution (NPSP). Meantime, the optimal design
and placement of BMPs would be different as well. The objective of this study was to discuss the relationship between the
spatial variability of rainfall and the optimal BMPs placements. Three synthetic rainfall storms with varied spatial distributions,
including uniform rainfall, downstream rainfall and upstream rainfall, were designed. WinVAST model was applied to predict
runoff and NPSP. Additionally, detention pond and swale were selected for being structural BMPs. Scatter search was applied
to find the optimal BMPs placement. The results show that mostly the total cost of BMPs is higher in downstream rainfall than
in upstream rainfall or uniform rainfall. Moreover, the cost of detention pond is much higher than swale. Thus, even though
detention pond has larger efficiency for lowering peak flow and pollutant exports, it is not always the determined set in
each subbasin. 相似文献
984.
Role of Geographic Information System (GIS) in Watershed Simulation By Winvast Model 总被引:2,自引:0,他引:2
The uncertainty of modeling input will increase the simulation error, and this situation always happens in a model without user-friendly interface. WinVAST model, developed by the University of Virginia in 2003, treats an entire multi-catchment by a tree-view structure. Its extra computer programs can connect geographic information system (GIS). Model users can prepare all the necessary information in ArcGIS. Extracting information from GIS interface can not only decrease the inconvenience of data input, but also lower the uncertainty due to data preparation. The Daiyuku Creek and Qupoliao Creek in the Fei-tsui reservoir watershed in Northern Taiwan provided the setting for the case study reported herein. The required information, including slope, stream length, subbasin area, soil type and land-use condition, for WinVAST model should be prepared in a Microsoft Access database, which is the project file of WinVAST with extension mdb. In ArcGIS interface, when the soil layer, land-use layer, and Digital Elevation Model (DEM) map are prepared, all the watershed information can be created as well. This study compared the simulation results from automatically generated input and manual input. The results show that the relative simulation error resulting from the rough process of data input can be around 30% in runoff simulation, and even reach 70% in non-point source pollution (NPSP) simulation. It could conclude that GIS technology is significant for predicting watershed responses by WinVAST model, because it can efficiently reduce the uncertainty induced by input errors. 相似文献
985.
Lin Kang Pao-Lin Kuo Ko-Hung Lee Yu-Chuan Liu Chiung-Hsin Chang Fong-Ming Chang Shio-Jean Lin 《黑龙江环境通报》2005,25(2):159-162
Galloway–Mowat syndrome (GMS) is a rare autosomal recessive disorder and is characterized by marked intrauterine growth retardation, central nervous system anomalies, and early onset nephrotic syndrome. Of the reported cases in the literature, all were diagnosed postnatally. We describe a case of GMS in which only late-onset intrauterine growth restriction was detected by prenatal ultrasound. In her fourth pregnancy, the mother had delivered a male baby with clinical features of GMS who died at seven months of age due to early onset of nephrotic syndrome. In her fifth pregnancy, serial ultrasound examinations were normal during the first and second trimester of pregnancy. Growth restriction and microcephaly were not detectable until 28 to 32 weeks' gestation. At 40 weeks' gestation, a female baby was born with dysmorphic features of GMS. Nephrotic syndrome developed after birth and renal biopsy revealed minimal change nephrotic syndrome. The prenatal course of this case suggests GMS may not be diagnosed in early pregnancy and the only abnormality detected before birth was intrauterine growth restriction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
986.
Tongwan City is one of the most famous and best-researched archaeological sites in China. By using palaeoclimatology proxy records from China over the last 2,000 years and archaeological/historical documents, we analyse the possible effect of climate on the collapse of Tongwan City, an ancient urban city of the Daxia state (AD 407–427). During Tongwan City’s existence (AD 413–994), two severe cold and drought stages were recorded by both natural proxy data and the synthesis compiled from the historical documents. The first cold and drought stage occurred at about AD 420–550, with the lowest point centred at about AD 500. The second cold and drought stage occurred at about AD 780–950. These periods correspond to the times of climate deterioration, especially weak summer monsoons, which eventually resulted in the intensive desertification and collapse of Tongwan City. 相似文献
987.
Siti Hafsyah Idris Lee Wei Chang Azizan Baharuddin 《Journal of Agricultural and Environmental Ethics》2013,26(4):747-757
Despite the (serious) global concerns about the safety and genetic stability of genetically modified organisms, the Malaysian National Biosafety Board (NBB) has recently approved the field testing for genetically modified (GM) male mosquitoes. With this development, bioethical issues, which in some respect could adversely impinge on the social, economic and environmental aspects of the society, have surfaced, and these concerns must be addressed by the authorities concerned. In reviewing this application, the National Biosafety Board has followed the requirements of the Biosafety Act 2007, which was created to strike a balance between promoting biotechnology and at the same time protecting against its potential environmental and human health risks in Malaysia. However, the 2007 Act fails to adequately take into account any bioethical issues in spite of the inclusion of a provision on socio-economic consideration. As part of an ongoing doctoral research project, and by way of an instrumental critique of the 2007 Act, the present paper attempts to address the role and function of the Malaysia biosafety legal framework in governing bioethical concerns relating to Genetically Modified Organisms (GMOs) within the current biotechnology background in Malaysia. Additionally, the paper suggests that the ambiguity of the provisions contained within the 2007 Act in governing such concerns, representing wider societal interests and welfare, in some ways might defeat the balancing role that this act was originally intended to fulfil. 相似文献
988.
Wang Wei Wang Shiyi Vakili Mohammadtaghi Wang Yan Sun Chang Yang Haoru Xiao Guotao Gong Minjuan Zhou Shuangxi 《Environmental science and pollution research international》2022,29(48):72545-72555
Environmental Science and Pollution Research - Herein, novel composite materials were prepared by intercalating functional pillars, i.e., pentafluorobenzene (PFB) and sodium... 相似文献
989.
Tsai CJ Chang CT Huang CH 《Journal of the Air & Waste Management Association (1995)》2006,56(6):834-840
The effect of ambient relative humidity (RH) on hourly particulate matter (PM10) readings of beta-gauge monitors has been studied using two collocated monitors in the field. The inlet air of monitor 1 was conditioned with water vapor to increase its RH, whereas monitor 2 operated normally in ambient conditions. Experimental data showed that PM10 readings of monitor 1 were nearly the same as monitor 2, as long as the RH of its conditioned incoming air did not exceed approximately 80-85%. However, when the RH exceeded approximately 80-85%, PM10 readings of monitor 1 became higher than monitor 2, and the difference increased with increasing RH. The measurement of pressure drop across the filter was also conducted, and the data revealed that the increase of pressure drop per unit of PM10 concentration decreased when RH was higher than approximately 80-85%, as compared with the case when RH was lower than 80-85%. This is perhaps because of more porous structure of deposited particles in the beta-gauge monitor when RH is greater than approximately 80-85%. The theoretical calculation using an evaporation model and a thermodynamic model has been conducted to simulate the beta-gauge readings. The results show that the theoretical PM10 concentrations using the evaporation model are in better agreement with the actual beta-gauge readings than those using the thermodynamic equilibrium model. 相似文献
990.
植物对二氧化硫的反应和抗性研究 Ⅷ.自由基清除剂对SO2伤害的保护作用 总被引:9,自引:0,他引:9
应用了五种自由基清除剂——苯甲酸钠、二苯胺,2.6二叔丁基对羟甲苯、生育醇(维生素E)和没食子酸丙酯来喷洒植株或涂抹叶片,然后接触致害浓度的SO_2。供试植物为芝麻、烟草、小麦、紫花苜蓿和辣椒五种。试验结果表明,预先经过这些药剂处理的植物,伤害有所减轻,外渗K+减少,与此同时,乙烷、丙二醛和荧光物质的产生也相应降低。自由基清除剂对SO_2伤害的保护作用说明在伤害过程中有自由基参与,它们引起膜类脂的过氧化作用。这些结果对膜类脂的过氧化是SO_2伤害过程的一个重要环节的假设提供了又一个证据。 相似文献