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141.
李创 《资源开发与保护》2013,(12):1295-1297
介绍了河南省产业集聚区的基本现状,包括规模现状、基础设施情况、招商引资情况和特色产业集聚区现状等,从产业集聚区自身的不足、产业集聚区内外部环境的约束和挑战、地方政府行为误区三个方面深度挖掘河南省产业集聚区面临的主要问题,提出相关对策建议.  相似文献   
142.
143.
Inkjet printing of metal nanoparticles is an attractive method for front-side metallization of silicon solar cells. It is owing to noncontact, low-cost, low-waste, and simple process. In this work, we proposed the ink-jet printing and electroless technology to fabricate the seed layer and electrode layer, respectively. Furthermore, we used electroplating method to increase the electrode conductivity. In this way, the energy conversion efficiency up to 12.22% without AR coating can be obtained on 100?×?100 mm c-Si cell.  相似文献   
144.
Since 1986, when green oysters occurred due to the copper and organic pollution in the Charting coastal area, the government banned all maricultural activity. It has been claimed that growing algae in a polluted environment may clean the water of pollutants and restore the marine ecosystem. to test this hypothesis, in the Charting coastal area a three-year programme (from August 1992 to July 1995) was carried out. the survey programme included environmental components such as salinity, temperature, pH, dissolved oxygen, biological oxygen demand (BOD), particulate organic carbon (POC), heavy metals and ecological indicators such as nutrients, chlorophyll-a, primary productivity. in the first year study, the environmental background data collected was used to select the suitable season and locations for growing large algae transferred from the laboratory to the field study area. Since September 1993, various species of large algae have been cultured. Although some of the growing algae were damaged by a typhoon in August 1994, the impact of the growing algae on the environmental conditions in the area has been monitored throughout. Elsewhere, we have reported that in the algae growing area higher dissolved oxygen with lower values of BOD and POC were found, and the concentrations of heavy metals in both water and sediments decreased. the purpose of this paper is to evaluate the possible impact of growing large algae on the ecological conditions in Charting coastal waters through the period from August 1983 to May 1995. As a result of the positive results obtained, large amounts of algae have again been cultured in the same area during the period from April 29 to May 25, 1995. We expect that inorganic and organic pollutants will be reduced by the algal growth, oyster mariculture will be restored and finally, the fishery resources potential will be increased.  相似文献   
145.
Metal capture experiments were carried out in an atmospheric fluidized bed incinerator to investigate the effect of sulfur and chlorine on metal capture efficiency and the potential for simultaneous capture of metal, sulfur and chlorine by sorbents. In addition to experimental investigation, the effect of sulfur and chlorine on the metal capture process was also theoretically investigated through performing equilibrium calculations based on the minimization of system free energy. The observed results have indicated that, in general, the existence of sulfur and chlorine enhances the efficiency of metal capture especially at low to medium combustion temperatures. The capture mechanisms appear to include particulate scrubbing and chemisorption depending on the type of sorbents. Among the three sorbents tested, calcined limestone is capable of capturing all the three air pollutants simultaneously. The results also indicate that a mixture of the three sorbents, in general, captures more metals than a single sorbent during the process. In addition, the existence of sulfur and chlorine apparently enhances the metal capture process.  相似文献   
146.
环境监测在处置气田的泄漏和火灾爆炸等事故中尤为重要,为应急决策提供科学依据。环境应急监测应针对气田特点选择监测仪器设备,确定监测内容和监测方案编制依据,做好应急监测准备工作,确保紧急情况下迅速、准确地完成监测任务,满足气田突发性事故应急救援工作的需要。  相似文献   
147.
In order to evaluate the association between placental thickness (PT) and fetal homozygous alpha-thalassaemia 1 before the appearance of classic ultrasound findings of haemoglobin (Hb) Bart's hydrops fetalis, a total of 473 pregnancies were collected. The control group included 422 normal pregnancies with a gestational age from 14 to 23 weeks and the study group included 51 affected fetuses in the same gestational period. Fetal biparietal diameter (BPD) and PT were measured by high-resolution ultrasound. PT was evaluated against BPD. In the control group, the PT generally increased in parallel with the advancement of gestational age. All PT measurements in the study group were above the mean PT of their respective gestational week in the control group. Forty-six (90 per cent) of the pregnancies in the study group had PT larger than the mean plus two standard deviations of the control group. This study suggests that ultrasound measurement of PT may be a useful aid in the prenatal diagnosis of Hb Bart's hydrops fetalis before its classic findings become apparent in the late second trimester or third trimester.  相似文献   
148.
采用酸、碱和金属盐表面修饰处理,影响氧化铝表面结构和成份分布,以达到提高吸附性能的目的。研究表明,经酸处理和酸性条件下的钙镁修饰处理的氧化铝,其对腐殖酸的吸附能力比Al-500分别提高32.3%和23.8%。同时,就改性氧化铝去除腐殖酸的影响条件、动力学、热力学性能进行了讨论。  相似文献   
149.
不同等级清洁生产评价指标的选择及在具体项目中应用   总被引:1,自引:0,他引:1  
在环境影响评价中,清洁生产分析是主要的组成部分,本文论述了清洁生产评价的主要内容,给出了不同评价等级中评价指标的选取方法,使清洁生产评价部分更加细致,精确.并将其应用于某实木复合地板环境影响评价中,实例证明清洁生产评价是使经济效益、社会效益和环境效益三赢的一个行之有效的方法.  相似文献   
150.
特种生物标志物作为溢油指示物(或指标)的研究   总被引:4,自引:1,他引:4  
用毛细管GC-MS对不同水环境中不同油类的特种生物标志物进行检测,结果表明,异戊二烯烷烃类姥鲛烷与植烷的比值在两个多月的风化过程中不受风化的影响;萜烷和甾烷的某些比值参数在一年的风化过程中(或室内自然放置4年)不受风化的影响。姥鲛烷与植烷的比值可以作为风化两个多月的溢油指示物(或指标);萜烷和甾烷比值可以作为风化一年(或室内自然放置4年)的溢油指示物(或指标)。  相似文献   
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