青霉菌P－93对偶氮染料的降解特性研究

采用富集培养的方法，从土壤中分离得到一株对偶氮染料酸性大红（ＧＲ）和酸性黑（ＡＴＴ）有较强脱色能力的青霉菌Ｐ－９３（Ｐｅｎｉｃｉｌｌｉｕｍｓｐ．Ｐ－９３）。该菌以ＧＲ和ＡＴＴ作为唯一Ｃ源和唯一Ｎ源均能生长。Ｐ－９３在ｐＨ４．０─８．０的范围内对ＡＴＴ的脱色率都在８０％以上，在２８－３７℃的温度范围内对ＧＲ和ＡＴＴ的脱色率也都超过８０％。对降解产物的紫外─可见光光谱分析表明，对ＧＲ和ＡＴＴ在可见光区的吸收峰（４８７．１ｎｍ，４８６．２ｎｍ和５９６．５ｎｍ）明显消失，而在紫外区的光吸收有所加强。Ｐ－９３中降解ＧＲ和ＡＴＴ的酶主要存在于细胞内，其生物合成不受染料的诱导。     

试论高校图书馆的隐性教育

本文说明了隐性教育的概念, 指出了高校图书馆隐性教育的功能, 并从教育主体的自主性、教育内容的素质性、教育方位的开放性、教育方式的潜隐性、教育评价的非程序性以及教育管理的预期性等六个方面论述了高校图书馆隐性教育的特性, 最后提出了深化物质性隐性教育、行为性隐性教育以及制度性隐性教育等深化高校图书馆隐性教育的三大途径.     

水分和氧气对毛萼田菁茎瘤固氮作用的影响

水分剥夺引起毛萼田菁（Ｓｅｓｂａｎｉａｒｏｓｔｒａｔａ）茎瘤固氮活性的下降；水分剥夺还导致茎瘤类菌体固氮的最适Ｏ２分压（ｐＯ２）和呼吸强度的下降及茎瘤豆血红蛋白和细胞质可溶性蛋白含量的下降。测定水分剥夺的茎瘤在不同ｐＯ２下的固氮活性和茎瘤组织切片的显微观察，支持水分胁迫可使Ｏ２扩散阻力增大这一观点。测定不同ｐＯ２下离体茎瘤固氮活性以ｐＯ２为６０％最高；当把茎瘤切碎后，茎瘤皮层的扩散屏障作用降低或失去，最适ｐＯ２降至４０％，说明Ｏ２是茎瘤固氮作用的限制因子。     

亚铁催化声化学降解罗丹明B

比较了不同金属离子对罗丹明B的声化学降解作用,发现超声时加入Fe2 反应速率常数为单独超声波降解时的1.6倍,反应在前5 h内符合假一级动力学.研究了亚铁离子强化声化学对罗丹明B的降解作用,考察了Fe2 用量,溶液初始pH值,曝气,反应温度和超声功率等因素对脱色速率的影响.研究表明,酸性条件有利于染料的脱色;有曝气时的声化学脱色速率常数是单独超声时的6倍;声化学反应的活化能较低,反应在低温就可以进行;超声功率的改变对脱色速率的影响不大.UV-VIS扫描图谱显示,染料在225 nm和256 nm处的紫外吸收明显降低,初步探讨了罗丹明B的降解机理.     

Catalytic destruction of dichloromethane using perovskite-type oxide catalysts

Dichloromethane (DCM, also known as methylene chloride [CH2Cl2]) is often present in industrial waste gas and is a valuable chemical product in the chemical industry. This study addresses the oxidation of airstreams that contain CH2Cl2 by catalytic oxidation in a tubular fixed-bed reactor over perovskite-type oxide catalysts. This work also considers how the concentration of influent CH2Cl2 (Co = 500-1000 ppm), the space velocity (GHSV = 5000-48,000 1/hr), the relative humidity (RH = 10-70%) and the concentration of oxygen (O2 = 5-21%) influence the operational stability and capacity for the removal of CH2Cl2. The surface area of lanthanum (La)-cobalt (Co) composite catalyst was the greatest of the five perovskite-type catalysts prepared in various composites of La, strontium, and Co metal oxides. Approximately 99.5% CH2Cl2 reduction was achieved by the catalytic oxidation over LaCoO3-based perovskite catalyst at 600 degrees C. Furthermore, the effect of the initial concentration and reaction temperature on the removal of CH2Cl2 in the gaseous phase was also monitored. This study also provides information that a higher humidity corresponds to a lower conversion. Carbon dioxide and hydrogen chloride were the two main products of the oxidation process at a relative humidity of 70%.     

氧化铁光催化降解活性染料的研究

用NaOH和Fe(NO3)3·9H2O共沉淀法制备Fe2O3的前驱体,分别在350℃,550℃,700℃烧结得到α-Fe2O3催化剂.通过对3种活性染料的降解实验,探讨了光照和光照时间的影响,比较了不同烧结温度下所得催化剂光催化活性的大小,得出350℃烧结的催化剂光催化活性最好.     

Case study I: application of the divalent cation bridging theory to improve biofloc properties and industrial activated sludge system performance-direct addition of divalent cations.

The objectives of this study were to examine the application of the divalent cation bridging theory (DCBT) to improve settling, dewatering, and effluent quality in pilot-scale reactors and a full-scale system treating an industrial wastewater. This was accomplished by lowering the monovalent-to-divalent (M/D) cation ratio by direct divalent cation addition. Research has shown that the M/D ratio is a potential indicator for settling and dewatering problems at wastewater treatment plants, and M/D ratios above 2 have been associated with poor settling, dewatering, and effluent quality. The M/D ratio of the wastewater in this study ranged from 6 to 20. The cations studied were calcium and magnesium. Results showed that the addition of calcium improved floc properties compared to control reactors with no calcium addition. The reductions in sludge volume index, effluent chemical oxygen demand (COD), and effluent total suspended solids (TSS) were approximately 35, 34, and 55%, respectively, when the M/D ratio was decreased to approximately 2:1. In addition, the cake solids from a belt filter press simulator increased by 72% and the optimum polymer dose required for conditioning was reduced by 70% in the reactor fed the highest calcium concentration when compared to control reactors with no calcium addition. The addition of calcium also decreased the negative effect of high filamentous organism numbers. In general, the addition of magnesium (Mg2+) had similar effects on effluent quality and dewatering properties, although some differences were measured. A full-scale test using calcium addition was performed. Measurements of effluent quality and floc properties were performed before, during, and after the calcium (Ca2+) addition period. The average M/D ratio during these periods was 6.2, 4.6, and 14.0, respectively. The addition of Ca2+ decreased the effluent five-day biochemical oxygen demand, effluent TSS, and effluent COD. The increased Ca2+ concentration also improved dewatering measured by a decrease in specific resistance to filtration and capillary suction time. Overall, the addition of divalent cations to the pilot- and full-scale activated sludge systems improved floc properties and the data fit well with the DCBT.     

Observation-based sources evolution of non-methane hydrocarbons (NMHCs) in a megacity of China

Both concentrations and emissions of many air pollutants have been decreasing due to implement of control measures in China, in contrast to the fact that an increase in emissions of non-methane hydrocarbons (NMHCs) has been reported. This study employed seven years continuous NMHCs measurements and the related activities data of Shanghai, a megacity in China, to explore evolution of emissions and effectiveness of air pollution control measures. The mixing ratio of NMHCs showed no statistical interannual changes, of which their compositions exhibited marked changes. This resulted in a decreasing trend of ozone formation potential by 3.8%/year (p < 0.05, the same below), which should be beneficial to ozone pollution mitigation as its production in Shanghai is in the NMHCs-limited regime. Observed alkanes, aromatics and acetylene changed by +3.7%/year, -5.9%/year and -7.4%/year, respectively, and alkenes showed no apparent trend. NMHCs sources were apportioned by a positive matrix factorization model. Accordingly, vehicular emissions (-5.9%/year) and petrochemical industry emissions (-7.1%/year) decreased significantly, but the decrease slowed down; significant reduction in solvent usage (-9.0%/year) appeared after 2010; however, emissions of natural gas (+12.6%/year) and fuel evaporation (with an increasing fraction) became more important. The inconsistency between observations and inventories was found in interannual trend and speciation as well as source contributions, emphasizing the need for further validation in NMHCs emission inventory. Our study confirms the effectiveness of measures targeting mobile and centralized emissions from industrial sources and reveals a need focusing on fugitive emissions, which provided new insights into future air policies in polluted region.     

罩壳锥面侧向冲孔模

介绍了锥面上冲孔用斜楔块代替立式凸模；中JL．改善了凸模的受力状况．并提高了模具寿命。     

CAF空穴气浮—生物接触氧化工艺在制革废水处理中的应用

介绍了一种皮革废水处理新工艺，即ＣＡＦ空穴气浮—接触氧化工艺。经预处理的制革综合污水采用ＣＡＦ系统混凝气浮，生物接触氧化工艺处理后，ＣＯＤＣｒ、ＢＯＤ５、ＴＳＳ、ＦＯＧ、硫化物以及总铬的去除率均在９５％以上，可达到回用标准。