KZNJ-1型高效口罩效率检测装置的研制

本文详细介绍了KZM-1型高效口罩效率检测装置的研制背景、检测原理和装置性能，实验研究结果表明：此检测装置的各项性能指标均达到国家标准GB19083和GB2626的要求。     

Chronic Toxicity of 1080 and its Implications for Conservation Management: A New Zealand Case Study

Sodium monofluoroacetate (1080) is a mammalian pesticide used in different parts of the world for the control of mammalian pest species. In New Zealand it is used extensively and very successfully as a conservation management tool for the control of brushtail possums (Trichosurus vulpecula) – an introduced marsupial that has become a substantial agricultural and conservation management pest. Possums pose a threat to cattle farming in New Zealand as they are a vector for bovine tuberculosis. In protected natural areas, possum browsing is responsible for large scale defoliation of native vegetation. As with many other pesticides, there has been some degree of popular concern about the use of this toxin and its safety, with particular reference to non-target effects. These concerns have been associated with potential non-target effects on human health, and the health of animals of recreational value (e.g., hunting dogs and game animals). This has led to the development of a strong “anti-1080” lobby in New Zealand. In contrast, this study encompasses a science-based risk analysis focusing on the potential risks to non-target native wildlife with a particular focus on chronic toxicity. It finds that there is evidence that 1080 may have endocrine disrupting capabilities (with potential relevance for non-target wildlife) but that this still needs more detailed investigation. This can be clarified by further targeted research. Further research is also needed to test the degradation rates of 1080 and its breakdown products at ecologically-relevant temperatures (i.e., winter stream temperatures – below 11 °C). Such research may demonstrate that some adjustment to 1080 risk management is warranted in New Zealand, or it may help to put to rest the current controversy over the use of this cost effective conservation management tool.     

Suppression of male reproduction in rats after exposure to sodium fluoride during early stages of development

Sodium fluoride (NaF), a widespread natural pollutant was given to sperm-positive female rats throughout gestation and lactation at a dose of 4.5 and 9.0 ppm via drinking water. The neonates were allowed to grow up to 90 days on tap water, and then sperm parameters, testicular steroidogenic marker enzyme activity levels, and circulatory hormone levels were studied. The sperm count, sperm motility, sperm coiling (hypoosmotic swelling test), and sperm viability were decreased in experimental rats when compared with controls. The activity levels of testicular steroidogenic marker enzymes (3β hydroxysteroid dehydrogenase and 17β hydroxysteroid dehydrogenase) were significantly decreased in experimental animals indicating decreased steroidogenesis. The serum testosterone, follicle stimulating hormone and luteinizing hormone levels were also significantly altered in experimental animals. Our data indicate that exposure to NaF during gestation and lactation affects male reproduction in adult rats by decreasing spermatogenesis and steroidogenesis.     

Effect of sodium alginate on phosphorus recovery by vivianite precipitation

There are good prospects for phosphorus recovery from excess sludge by vivianite crystallization while a large number of extracellular polymeric substances in sludge will have impact on vivianite precipitation. In this study, as a representative of extracellular polymeric substance, the effect of sodium alginate (SA) on phosphorus recovery by vivianite precipitation under different initial SA concentrations (0–800 mg/L), pH values (6.5–9.0) and Fe/P molar ratios (1:1–2.4:1) was investigated using synthetic wastewater. The results showed that SA in low concentrations (≤400 mg/L) had little inhibitory effect on the phosphorus recovery rate. However, when the concentration of SA was larger than 400 mg/L, the phosphorus recovery rate decreased significantly with increasing SA concentrations. The inhibition rate of 800 mg/L SA was about 3 times as large as that of 400 mg/L SA. It was worth noting that the inhibitory effect of SA on vivianite precipitation decreased with increasing initial pH and Fe/P molar ratios. Additionally, SA has no obvious influence on the composition of products, but the morphology of harvested crystals was transformed from branches to plates or rods in uneven sizes.     

蜡样芽孢杆菌中甲酸脱氢酶基因产氢研究

通过基因筛选,成功分离并克隆到蜡样芽胞杆菌XN12（Bacillus cereus XN12）的甲酸脱氢酶基因fdhF（formate dehydrogenase）,该基因全长2937bp,GC含量39.3%,编码978个氨基酸,与已报道的蜡样芽孢杆菌Q1的fdhF基因（GenBank No.CP000227.1）同源性达到100%.将其连接在表达载体pET32a上并融合His标签,构建了重组质粒pET32a-FDHF-His,转入大肠杆菌BL21（Escherichia coli BL21）后获得了高效表达.重组菌株经IPTG诱导后经WesternBlot分析表明,重组蛋白分子量约为108kDa.通过对重组菌株产氢性能试验表明,重组菌对提高产氢率具有一定促进作用,产氢量为每消耗1mol的葡萄糖和甲酸盐分别能产生0.73mol和0.20mol的氢气.     

The effect of male sodium diet and mating history on female reproduction in the puddling squinting bush brown<Emphasis Type="Italic"> Bicyclus anynana</Emphasis> (Lepidoptera)

The males of butterflies transfer a spermatophore to the female during mating that can contain nutrients enhancing the reproductive potential of their partners. The nutrients transferred by males can be derived from both larval and adult feeding. These nutrients may be depleted by multiple matings. An apparent difference in adult feeding behaviour between the sexes is puddling on mud, dung and carrion, which in most butterfly species is exclusively a male behaviour. A possible explanation for this division in feeding behaviour is that nutrients derived from puddling by males are transferred to the female during mating. Here, we test this hypothesis in the African fruit-feeding butterfly Bicyclus anynana. We varied the male nuptial gift by (1) feeding males either a diet with or without sodium, and (2) varying the number of previous successful copulations by remating males up to five times on consecutive days. The results show both a strong effect of order of mating on the mating duration, and an individual effect with some males typically copulating for a shorter time than others. The effects on female reproduction were, however, minimal. The total number of eggs per female and the sodium content of the eggs did not differ significantly between diets, nor were they affected by the mating histories of the males. Eggs showed a non-significant lower hatching for females partnered by a male who had already mated several times. There was an indication of an interaction with male diet: the sodium treatment showing a decline in egg hatchability with order number of male mating, whilst the control treatment showed a constant hatchability. The results are discussed in relation to determinants of male gift-giving strategy and to other potential explanations for a restriction of puddling to males in butterflies.Communicated by M.A. Elgar     

Reaction of ortho-methoxybenzoic acid with the water disinfecting agents ozone, chlorine and sodium hypochlorite

Ozone, chlorine and sodium hypochlorite are commonly used as disinfecting agents for drinking water production. The reaction pathways of ozonation and chlorination of o-methoxybenzoic acid in aqueous solution were studied using gas chromatography-mass spectrometry (GC-MS) and high pressure liquid chromatography (HPLC). The results show that less than 1% of o-methoxybenzoic acid remains in reaction. The final major products using ozone oxidation are oxalic and glyoxalic acids. Phenols appear only at insufficient ozone levels. Sodium hypochlorite leads to higher levels of primary products. Molecular chlorine leads to the formation of higher amounts of polychlorinated derivatives. Model experiments allow to propose schemes of o-methoxybenzoic acid transformation under the conditions simulating water treatment processes.     

Waste activated sludge hydrolysis and acidification: A comparison between sodium hydroxide and steel slag addition

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA (volatile fatty acid) in a shorter time can be achieved at pH 10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supernatant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most phosphorus was released and captured by steel slag simultaneously in steel slag addition scenarios. These results suggest that steel slag can be used as a substitute for NaOH in sludge alkaline treatment.     

十二烷基苯磺酸钠的微生物降解

从长期受十二烷基苯磺酸钠(sodiumdodecylbenzenesulfonate,SDBS)污染的土壤中,筛选到3株对SDBS降解能力很强的细菌,分别为荧光假单胞杆菌(PseudomonasfluorescensP-11)、芽孢杆菌(Bacilussp.B-24)、气单胞菌(Aeromanassp.A-2)。3株细菌均属中温细菌,最适生长温度为30℃,最适生长pH为7.0,在低浓度SDBS中生长比在高浓度中生长好。在选定的最适条件下,测定了3株菌对SDBS的降解能力,在含40mg/LSDBS的培养基上,于28℃生长72h,SDBS的降解率均超过95%,其中P-11达100%。