不同配比安全点火药B/KNO_3的研究

为研究可靠点燃主装药,性能稳定的B/KNO3点火药,对不同配比的B/KNO3进行配制并对其性能进行测试。不同配比B/KNO3在火焰感度、静电火花感度、撞击感度、摩擦感度4项外界刺激中,除了对撞击非常钝感之外,对其他3项外界刺激敏感。在不同比例的药中,以B/KNO3比例为50:50,粘结剂为X的药火焰感度最高,稳定性好;静电火花感度随B/KNO3中B比例提高而降低,摩擦感度随B/KNO3中B比例提高而提高,但当中B比例从40%提高到50%时,这两感度改变不多。分析得出B/KNO3比例为50:50,粘结剂为X的药满足对主装药点火可靠,稳定性好。     

有机粘土矿物对水中菲蒽混合物的吸附

选用长碳链季铵盐阳离子型表面活性剂十六烷三甲基溴化铵(HDTMA-Br)作为改性剂对天然粘土矿物进行改性。利用改性后的粘土矿物对混合污染物进行吸附/解吸实验,结果显示:HDTMA改性粘土矿物对混合溶液中菲、蒽及混合物的吸附等温线均呈线性,是分配作用结果;随着改性土用量的增加,其吸附量逐渐减小,对污染物的去除率逐渐增大,最后趋于平衡;有机粘土矿物吸附混合污染物后解吸率均在5%以下;将改性土对混合污染物的吸附与对单体污染物的吸附进行对照,改性土总的吸附量大大增加,基本是对单体污染物的吸附量之和。     

Effect of a heavy metal model mixture on biological parameters of rainbow trout <Emphasis Type="Italic">oncorhynchus mykiss</Emphasis>

The effects of a model mixture (HMMM) of seven heavy metals (Cu, Zn, Ni, Cr, Pb, Cd, Mn) on the rainbow trout Oncorhynchus mykiss at all stages of development (embryos, larvae, adults) were investigated based on the annual average concentrations of these metals in cooling waste waters discharging from Ignalina Nuclear Power Plant (Lithuania) into the Drūk?iai lake. According to mortality parameters, the most sensitive to HMMM were larvae, although no significant differences between the sensitivity of embryos and adult fish to HMMM were found. Maximal toxic effect of HMMM was observed during the hatching period. Long-term exposure to sublethal concentrations of HMMM affected embryo development, growth of larvae, their cardio-respiratory and behavioural responses, induced significant changes in morphological, morpho-physiological, physiological and haematological parameters of adult fish. Respiratory responses and growth parameters of fish were found to be the most sensitive to low concentrations of HMMM. Adult fish were capable of detecting and avoiding low, sublethal concentrations of HMMM. Heavy metals in a mixture at low concentrations were more toxic than single ones. According to the background of the damages induced by HMMM, after-effects in a fish organism, as well as in a whole population, can be predicted.     

煤吸附硫化氢混合气体的试验研究*

为研究煤层硫化氢（H2S）吸附特性,厘清煤层H2S赋存规律及改善H2S防治效果,采用分压测试法研究煤对H2S的吸附规律。以山西保利铁新煤业有限公司9#煤为研究对象,分别使用N2,He/H2S,N2/H2S为吸附介质开展等温吸附试验,分析煤对H2S及含H2S混合气体的吸附特性及影响因素。结果表明:煤对H2S的吸附量随压力升高而增加,随温度升高而降低,且温度对煤吸附H2S吸附量影响较大;H2S及N2/H2S混合气体的吸附曲线均符合Langmuir吸附模型,煤吸附N2/H2S混合气体时,H2S和N2存在竞争吸附,且N2吸附能力优于H2S;等温条件下,N2竞争吸附量随吸附压力的增加而增大,等压条件下,N2的竞争吸附量受温度影响较小。     

多种环境雌激素对淡水鱼联合毒性作用的预测和评价

为预测和评价多种环境激素对生物的联合毒性效应,通过对雄性鲫鱼卵黄蛋白原诱导作用探讨了17β-雌二醇、17α-乙炔基雌二醇、双酚A、辛基苯酚等几种环境雌激素联合作用的环境影响.确定了每种化合物的剂量-效应曲线,混合物由单个化合物等毒性固定浓度比例混合而成,实验得出的混合物效应与通过浓度相加或反应相加作用模型计算得出的混合物效应比较.结果有很好的一致性.上述结果证明了类雌激素化合物呈现相加作用方式,即使在单独作用无显著效应的较低浓度下也可产生显著的混合物效应,混合物效应可通过两类模型预测.由于环境污染物组成往往不明确,通过浓度相加作用模型预测的结果较为保守,在环境风险评价中更加实用.     

Human dietary intake and hazard characterization for residues of neonicotinoides and organophosphorus pesticides in Egyptian honey

In two recently published reports, hazards posed by dietary exposure to organophosphate and neonicotinoid plant protection products on the European honey bee (Apis mellifera L.) in Egypt were investigated. Using concentrations reported in those studies, an assessment of hazards posed by these two classes of insecticides to humans due to consumption of Egyptian honey from the Nile Delta during both spring and summer was performed. Twenty-eight compounds including metabolites were assessed for exposure of adult Egyptians based on the best- and worst-case scenarios. Even for the worst-case scenario, exposure to these two classes of pesticides in honey was 15-fold less than hazard index value of 1.0 for adverse effects on humans. Based upon this analysis, people exposed to these insecticides through consumption of honey products would be unlikely to exhibit adverse health outcomes.     

In vitro evaluation of the mutagenic and cytostatic effect of Tamaron,Lannate and Manzate alone and in mixture

Pesticides are often used in agriculture, especially in floriculture. They are frequently applied in binary or ternary mixtures. Nevertheless, their impact on the genetic material has been scarcely explored. In this study, the mutagenic and cytostatic effect of three widely used pesticides, alone and combined, were analyzed. Briefly, lymphocytes cultures were obtained from peripheral blood samples of five healthy donors to determine the sister chromatid exchange and the replicative index (RI). Then, lymphocytes were exposed to Tamaron (100 ppm), Lannate (200 ppm) and Manzate (300 ppm) alone and combined. For the binary mixtures, the concentrations used were 50 ppm of Tamaron, 100 ppm of Lannate and 150 ppm of Manzate. For the ternary mixtures the following concentrations were used: Tamaron (33 ppm), Lannate (70 ppm) and Manzate (100 ppm). Finally, differential staining was performed. It was found that the frequency of SCE/cell showed a significant difference (P ≤ 0.05) between the control (2.66) and the individual treatments of Tamaron (4.87), Lannate: (5.12) and Manzate (4.23). Also, the values of the SCE in the binary mixture of Tamaron+Lannate (5.57), Tamaron+Manzate (6.06) and Lannate+Manzate (6.22) and the ternary mixture (6.63) were statistically different compared to the control. In the RI there was a significant difference between the control (1.98) and the Manzate (1.87). RI differences were also statistically significant (P ≤ 0.05) in mixtures of Tamaron+Lannate (1.64), Tamaron+Manzate (1.63), Lannate+Manzate (1.69) and total mixture (1.53). Therefore, it is suggested that these pesticides alone and in mixtures have both mutagenic and cytostatic synergistic effect in human lymphocytes in vitro.     

Sodium bisulfate and a sodium bisulfate/tannin mixture decreases pH when added to an in vitro incubated poultry cecal or fecal contents while reducing Salmonella Typhimurium marker strain survival and altering the microbiome

The objective of the present study was to investigate the ability of animal feed-grade sodium bisulfate (SBS) and a mixture of sodium bisulfate/tannin to inhibit the growth of Salmonella using an anerobic in vitro mixed cecal culture to mimic the conditions within the chicken cecum. An initial inoculum of Salmonella Typhimurium was introduced to an anerobic dilution solution containing 1/3000 diluted cecal bacteria and solids consisting of ground chicken feed and different percentages of solid SBS or SBS/tannin, and surviving organisms were enumerated. Two different experimental designs were employed. In the “unadapted” treatment, the S. Typhimurium was added at the beginning of the culture incubation along with cecal bacteria and chicken feed/SBS or chicken feed/SBS/tannin. In the “adapted” treatment, S. Typhimurium was added after a 24 hour pre-incubation of the cecal bacteria with the chicken feed/SBS or chicken feed/SBS/tannin. Adding SBS resulted in reduction of pH in the cultures which paralleled with the reduction of S. Typhimurium. The SBS alone was found to be inhibitory to S. Typhimurium in the adapted treatment at all concentrations tested (0.25, 0.5, and 0.75%), and the degree of inhibition was concentration-dependent. Salmonella Typhimurium was completely killed in the adapted culture with 0.5% SBS after 24 and 48 h. The SBS/tannin mixture was less inhibitory than SBS alone at the same concentrations in side-by-side comparisons. Testing at a 0.5% SBS concentration, chicken age had little or no effect on log reduction of S. Typhimurium relative to age-matched control cultures without SBS, but age did affect the absolute number of S. Typhimurium surviving, with the greatest decreases occurring at 2 and 4 weeks of age (approx. 10³ S. Typhimurium surviving) compared to 6 weeks of age (approx. 10⁵ Salmonella surviving). Microbiome analysis with an Illumina MiSeq platform was conducted to investigate bacterial compositional changes related to the addition of SBS. The relative abundance of Firmicutes (at the phylum level) was decreased, and genera Lactobacillus and Faecalibacterium were increased when SBS was added to the anaerobic mixed culture containing either fecal or cecal material. The antimicrobial action of feed-grade SBS may represent a potential pre-harvest control measure for Salmonella in poultry production.     

自然通风房间内细水雾与油池火作用的数值模拟

采用大涡模拟、混合物分数燃烧模型和欧拉-拉格朗日粒子运动描述法,对自然通风房间内细水雾与油池火焰作用过程进行数值模拟;探讨细水雾在火羽流的不同区域内的灭火机理;分析雾滴直径在自然通风条件下对细水雾灭火效果的影响。模拟结果表明:细水雾冷却热烟气层分为温度迅速降低和缓慢下降两个阶段;在间歇火焰区和浮力羽流区以及热烟气层主要发挥细水雾的蒸发冷却作用,在恒定火焰区则是蒸发冷却和隔氧窒息共同作用;着火区域封闭性较差时,直径较小的水雾系统的灭火效果较低。     

无缝钢管厂外排废水治理方案

针对无缝钢管厂酸洗废水pH值低、氧化铁含量高等特殊性，采用分散治理回收与集中处理回收相结合的技术方案。使处理后的水回用于生产，并采用一水多用、重复利用和循环利用的技术，提高了重复用水率，基本上实现“零排放”。