云朝山雷达站10KV线路雷害分析与防雷措施的研究

该文对张家界云朝山雷达站的雷电活动规律、雷害事故和原有防雷措施进行了认真探讨.结合雷电活动选择性原理深入分析该雷达站雷害事故,指出沿10kv线路来的雷电侵入波是造成雷害的主因.针对原防雷措施在对线路入侵波保护、配电变压器防雷、低压电源保护、接地及等电位联接方面存在的薄弱环节,重点阐述高海拔地区10kv线路的防雷关键措施...     

17α-乙炔基雌二醇降解菌的分离鉴定及降解特性

从避孕药生产厂废水处理站的活性污泥中驯化、分离到1株能够以17α-乙炔基雌二醇(17-αethynylestradiol,EE2)为唯一碳源和能源生长的菌株JCR5.经过对其形态特征、生理生化以及16S rDNA序列分析,该菌株为鞘氨醇杆菌属(Sphingobacterium sp.).研究表明,菌株JCR5利用EE2生长的适宜温度为25～40℃,培养基初始pH为7～9.金属离子Ni²⁺、Mn²⁺、Cu²⁺、Fe³⁺能够促进菌株的生长,而Zn²⁺、Ag⁺、Pb²⁺、Ca²⁺和Al³⁺离子对菌株的生长具有不同程度的抑制作用.菌株JCR5在10d内对初始底物浓度为30mg·L^-1EE2的降解率可达到87%.     

Cu-Ag/海泡石催化还原NO的研究

以天然海泡石为原料,对其进行酸改性并与活性氧化铝混合后作为催化剂载体,采用浸渍法制备了用于CO还原NO的Cu-Ag复合金属催化剂.对不同Ag负载量催化剂催化还原NO的活性进行了评价,考察了载体对催化剂催化活性的影响,用BET、XRD、SEM等对催化剂进行了表征.结果表明,当Ag负载量不超过5%时,复合金属催化剂性能好于单一金属催化剂;Ag负载量为2%时催化剂性能最好;采用海泡石-氧化铝混合物为载体的催化剂的孔径分布得到改善,对NO催化还原反应有更高的活性.     

浅谈我国城市环境综合整治的途径

本文从我国城市环境的现状出发，阐述了我国城市环境保护的历程，并在理论分析的基础上，提出了我国目前城市综合整治的基本途径。     

Au/SnO2催化氧化CO性能的研究

以SnO2为载体,Au为活性组分,采用真空浸渍法、共沉淀法、沉积-沉淀法制备CO氧化的催化剂,同时还制备双金属体系催化剂Au-Pd/SnO2和Au-Pt/SnO2.用气相色谱对所制备的催化剂进行活性评价,运用DSC、SEM、XRD、BET等对催化剂进行表征.在本实验条件下,载体二氧化锡焙烧温度为500℃,催化剂成型温度为350℃,金负载量为3%(wt.)时,用沉积.沉淀法制备的Au/SnO2活性最好,在18℃,空速为24 000 h-1条件下就能将CO(浓度为4%)完全氧化为CO2;添加铂和钯可提高Au/SnO2对CO的催化活性.     

改性活性炭对苯的吸附性能

本文研究了用H_3PO_4,SN (以 NaNO_2为主的复盐) 等改性的活性炭对苯的吸附性能,在不同苯浓度和空述下,经适当改性的活性炭对苯的吸附容量大于活性炭本身,探讨了改性活性炭的表观比表面与其吸附性能的关系。     

Removal of petroleum tar from bird feathers utilizing magnetic particles

A previously reported acute temperature dependency for the effective removal of tarry residue from feather clusters, utilising magnetic particles, has also been demonstrated to occur for the plumage of whole birds, whereby a maximum removal of up to 96% may be achieved. The experimental design allows an approximate equilibrium constant, for the distribution of contaminant between the residue and the magnetic particles, to be estimated at each temperature. This allows the thermodynamics of the process to be examined via application of the van't Hoff equation, suggesting an explanation for the phenomenon.     

Acute temperature dependency in the cleansing of tarry feathers utilizing magnetic particles

We have conducted temperature-dependent studies on the removal of a solidified tarry residue from feathers using magnetic particles. These studies demonstrate an acute temperature dependency whereby no contaminant at all is removed below a certain temperature but, at and above this temperature, the removal rapidly approaches 100%. Significantly, this temperature is well below the temperature at which the tarry residue becomes a flowing liquid. This demonstrates that it is possible for magnetic cleansing to remove up to 100% of tarry residue from feathers under temperature conditions that would be benign to a bird.     

Phosphorus extractability of soils amended with stockpiled and composted cattle manure

Managing fertilizer applications to maintain soil P below environmentally unacceptable levels should consider the contribution of manure and synthetic fertilizer sources to soluble and extractable forms of P. Our objective was to evaluate soil and manure characteristics and application rates on P extractability in recently amended soils. Five soils of the U.S. southern High Plains were amended with beef cattle manures, composted beef manure, and inorganic fertilizers [Ca(H(2)PO(4))(2) or KH(2)PO(4)] at five rates and incubated under controlled conditions. Mehlich 3-, Olsen (NaHCO(3))-, Texas A&M extractant (TAM)-, and water-extractable P were determined for the soils after selected incubation periods. Except for TAM and some water extractions, P extractability as a function of total P applied was linear (P < 0.001) for a wide range of application rates. Mehlich-3, NaHCO(3), and water P extraction efficiencies of KH(2)PO(4)-amended soils averaged 22, 34, and 115% greater (P < or = 0.036), respectively, than efficiencies of soils amended with manures except for the Texline (calcareous) loam and Pullman clay loam soils. Phosphorus extraction efficiencies decreased with time for KH(2)PO(4)-amended soils (P < 0.05) but remained stable or increased for manure-amended soils during the 8-wk incubation period. Across all soils and manure sources, changes in water-extractable P per unit increase in Mehlich 3-, NaHCO(3)-, and TAM-extractable P averaged 100, 85, and 125% greater, respectively, for inorganic as compared with manure-amended soils. These source-dependent relationships limit the use of agronomic soil extractants to make correct inferences about water-extractable P and dissolved P in runoff.     

Particulate and dissolved phosphorus chemical separation and phosphorus release from treated dairy manure

In confined animal feeding operations, liquid manure systems present special handling and storage challenges because of the large volume of diluted wastes. Water treatment polymers and mineral phosphorus (P) immobilizing chemicals [AI2(SO4)3 x 18H2O, FeCl3-6H2O, and Class C fly ash] were used to determine particulate and dissolved reactive phosphorus (DRP) reduction mechanisms in high total suspended solid (TSS) dairy manure and the P release from treated manure and amended soils. Co-application exceeded the aggregation level achieved with individual manure amendments and resulted in 80 and 90% reduction in metal salt and polymer rates, respectively. At marginally effective polymer rates between 0.01 and 0.25 g L(-1), maximal aggregation was attained in combination with 1 and 10 g L(-1) of aluminum sulfate (3 and 30 mmol Al3+ L(-1)) and iron chloride (3.7 and 37 mmol Fe3+ L(-1)) in 30 g L(-1) (TSS30) and 100 g L(-1) TSS (TSS100) suspensions, respectively. Fly ash induced particulate destabilization at rates > or = 50 g L(-1) and reduced solution-phase DRP at all rates > or = 1 g L(-1) by 52 and 71% in TSS30 and TSS100 suspensions, respectively. Aluminum and Fe salts also lowered DRP at rates < or = 10 g L(-1) and higher concentrations redispersed particulates and increased DRP due to increased suspension acidity and electrical conductivity. The DRP release from treated manure solids and a Typic Paleudult amended with treated manure was reduced, although the amendments increased Mehlich 3-extractable P. Therefore, the synergism of flocculant types allowed input reduction in aggregation aid chemicals, enhancing particulate and dissolved P separation and immobilization in high TSS liquid manure.