低剂量浓缩铀对脾淋巴细胞DNA合成和UDS效应

研究机体摄入浓缩铀²³⁵UO₂F₂时,对外周免疫器官脾淋巴细胞DNA合成和UDS的影响。观察发现,当摄入低剂量浓缩铀0.1μg/kg体重时,可刺激T淋巴细胞的转化增殖,刺激指数增升。低剂量位缩铀摄入水平在0.1～20μg/kg体重时,可使紫外线诱导的脾淋巴细胞UDS呈现明显刺激效应,增强对脾淋巴细胞DNA切除修复能力。当浓缩铀内污染水平进一步加大时,可使脾T、B淋巴细胞的DNA合成以及UDS都呈现明显抑制。     

Co/Al2O3催化剂上CH4的CO2重整反应研究

通过研究不同Ｃｏ负载量的Ｃｏ／Ａｌ２Ｏ３催化剂对ＣＨ４的ＣＯ２重整剂合成气活性的影响,发现Ｃｏ负载量为１３％（Ｗｔ）的Ｃｏ／Ａｌ２Ｏ３活性最好,考察了反应温度,空速,还原温度等对催化剂活性和产物中ＣＯ／Ｈ２比例的影响,结果表明反应温度升高,ＣＨ４的ＣＯ２的转化率均增加,但随空速的增加而降低,还原温度在４００℃时催化剂显示出活性最好,产物中ＣＯ／Ｈ２的比例,随反应条件不同而略有增减。     

半导体材料生产废水中的GaAs、Ga3+和Ge4+对活性污泥核酸和氨基酸的影响

研究了GaAs、Ga³⁺、Ge⁴⁺、Hg²⁺和Cr⁶⁺对活性污泥脱氧核糖核酸(DNA)和核糖核酸(RNA)的影响,以及GaAs对活性污泥氨基酸的影响。结果表明,Hg²⁺和Cr⁶⁺主要使活性污泥中核酸的DNA含量减少,GaAs则主要使RNA含量减少,Ge⁴⁺浓度达到300ppm/g MLSS对,无论对DNA还是RNA的合成都有较强的抑制影响。低浓度的GaAs对活性污泥氨基酸含量影响不大,而GaAs浓度达360ppm/g MLSS时则使活性污泥中氨基酸含量明显减少。     

Improved utilization of active sites for phosphorus adsorption in FeOOH/anion exchanger nanocomposites via a glycol-solvothermal synthesis strategy

Metal oxide/hydroxide-based nanocomposite adsorbents with porous supporting matrices have been recognized as efficient adsorbents for phosphorus recovery. Aiming at satisfying increasingly restrictive environmental requirements involving improving metal site utilization and lowering metal leakage risk, a glycol-solvothermal confined-space synthesis strategy was proposed for the fabrication of Fe OOH/anion exchanger nanocomposites（Fe/900s）with enhanced metal site utilization and reduced metal lea...     

有机磷农药通用人工抗原的合成与鉴定

用O,O-二乙基硫代磷酰氯与4-氨基丁酸反应,合成了新型有机磷农药通用半抗原O,O-二乙基-N-(3-羧基丙基)硫逐磷酰胺酯(DENP),并进行了结构鉴定.然后采用碳二亚胺法将DENP与牛血清白蛋白(BSA)进行偶联,制备了通用人工抗原DENP-BSA,经鉴定,DENP-BSA结合比为12:1,适合进行动物免疫试验。     

Numerical validation of a Eulerian hydrochemical code using a 1D multisolute mass transport system involving heterogeneous kinetically controlled reactions

It is demonstrated that at steady state, the 1D thermo-kinetic hydrochemical Eulerian mass balance equations in pure advective mode are indeed identical to the governing mass balance equations of a single reaction path (or geochemical) code in open system mode. Thus, both calculated reaction paths should be theoretically identical whatever the chemical complexity of the water-rock system (i.e., multicomponent, multireaction zones kinetically and equilibrium-controlled). We propose to use this property to numerically test the thermo-kinetic hydrochemical Eulerian codes and we employ it to verify the algorithm of the 1D finite difference code KIRMAT. Compared to the other methods to perform such numerical tests (i.e., comparisons with analytical, semi-analytical solutions, between two Eulerian hydrochemical codes), the advantage of this new method is the absence of constraints on the chemical complexity of the modelled water-rock systems. Moreover, the same thermo-kinetic databases and geochemical functions can be easily and mechanically used in both calculations, when the numerical reference comes from the Eulerian code with no transport terms (u and D = 0) and modify to be consistent with the definition of the open system mode in geochemical modelling. The ability of KIRMAT to treat multicomponent pure advective transport, subjected to several kinetically equilibrium-controlled dissolution and precipitation reactions, and to track their boundaries has been successfully verified with the property of interest. The required numerical validation of the reference calculations is bypassed in developing the Eulerian code from an already checked single reaction path code. A forward time-upstream weighting scheme (a mixing cell scheme) is used in this study. An appropriate choice of grid spacing allows to calculate within the grid size uncertainty the correct mineral reaction zone boundaries, despite the presence of numerical dispersion. Its correction enables us to improve the convergence and to extend the numerical test to mixed advective-dispersive mass transport. However, the skewness factor involves numerical oscillations that prevent to compute different grid spacing. The use of a different chemically controlled time step constraint in both calculations induces some inconsistencies into the validation tests. This numerical validation method may be applied as well as to check a thermo-kinetic hydrochemical finite element based code, from a 1D heterogeneous systems, and 2D-3D systems provided that they are designed so as to be 1D equivalent. A one-step algorithm and the use of a numerical reference coming from the Eulerian code to be tested ensure the potential success (accuracy) of the numerical validation method.     

环保型脲醛树脂胶粘剂的合成研究

介绍了聚乙烯醇(PVA)、三聚氰胺在脲醛树脂胶粘剂合成过程中所起的改性作用,研究了反应温度、反应体系pH、甲醛与尿素摩尔比、PVA和三聚氰胺用量对脲醛树脂胶粘剂性能的影响。试验结果表明,在反应温度为80℃、反应体系pH为5．0、甲醛与尿素摩尔比为1．5、PVA和三聚氰胺用量分别为尿素与甲醛溶液总质量的1．0％和5％的条件下,合成的脲醛树脂胶粘剂的剪切强度为2．99MPa,游离甲醛的质量分数由传统工艺生产产品的0．6％～0．8％降低至0．063％,耐沸水时间为108min,且贮存稳定性好,达到了HJBZ-1998国家环境标志产品技术要求。     

PFS-PS硅铁絮凝剂的合成形态及应用研究

实验采用活化硅酸 ,自制聚合硫酸铁为原料 ,在不同碱化度和Si/Fe摩尔比条件下 ,制备出聚合硅酸硫酸铁 (PFS PS)无机高分子絮凝剂。考察影响产品稳定性的因素 ,分析了产品Fe(Ⅲ ) ,Si(Ⅳ )的形态分布特征。并以炼油厂浮渣为处理对象 ,对影响硅铁絮凝剂絮凝性能的合成因素进行了考察。     

(S)-2-Methyl-1-hexanol,characteristic mandibular gland substance of ants of theCataglyphis bicolor group

Summary In all the species of theCataglyphis bicolor group examined yet, i.e.C. bicolor, C. diehli, C. isis, C. nodus, andC. viaticus, 2-methyl-1-hexanol is the characteristic substance and almost the only substance found in the mandibular glands. Its chirality has been determined inC. bicolor and shown to be exclusively (S)-2-methyl-1-hexanol.     

Toxicity of new pyrethroid in pest insects Asciamonuste and Diaphania hyalinata,predator Solenopsis saevissima and stingless bee Tetragonisca angustula

There is increasing demand for new products for vegetable pest management. Thus, the aim of this study was to assess the toxicity of pyrethroids with acid moiety modifications to measure the insecticidal activity of these compounds on the lepidopteran vegetable pests Diaphania hyalinata (L.) (Lepidoptera: Pyralidae) and Asciamonuste (Latreille) (Lepidoptera: Pieridae) and evaluate their selectivity for the predatory ant Solenopsis saevissima (F. Smith) (Hymenoptera: Formicidae) and pollinator Tetragonisca angustula (Latreille) (Hymenoptera: Apidae: Meliponinae). Racemic mixtures of five new pyrethroids (30 µg molecule mg^?1 insect body weight) resulted in high (100%) and rapid (stable LD₅₀ after 12 h) mortality in D. hyalinata and A. monuste. In A. monuste, the trans-pyrethroid [12] isomer showed similar toxicity to permethrin. For D. hyalinata, the trans-pyrethroid [9] isomer and cis-pyrethroid [10] isomer were as toxic as permethrin. Due to their low selectivity, these new pyrethroids should be applied on the basis of ecological selectivity principles to minimize impacts on nontarget organisms S. saevissima and T. angustula.