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141.
142.
Olfa Bachrouch Jouda Mediouni-Ben Jema Aidi Waness Wissem Thierry Talou Brahim Marzouk Manef Abderraba 《Journal of Stored Products Research》2010,46(4):242-247
This study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), α-terpineol (7.12%) and β-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC50 = 1.84 μl/l, LC95 = 5.14 μl/l) than E. ceratoniae (LC50 = 3.29 μl/l, LC95 = 14.24 μl/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 μl/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella. 相似文献
143.
Extracts of 40 species of Chinese medicinal herb from 32 different botanical families were screened for contact, fumigant and feeding-deterrent activities against the two stored-grain insects Sitophilus zeamais and Tribolium castaneum. Thirty Chinese medicinal herbs exhibited insecticidal or feeding-deterrent activities against the two species of insects. Extracts of Artemisia argyi, Dictamnus dasycarpus, Evodia rutaecarpa, Litsea cubeba, Narcissus tazetta var. chinensis, Polygonum aviculare, Rhododendron molle, Sophora flavescens, Stemona sessilifolia, Tripterygium wilfordii, and Torreya grandis were most active. 相似文献
144.
This paper describes a flow-through toxicity testing system utilizing a new exposure chamber designed for microscopic organisms. Typically, flow-through testing is conducted with either a serial or proportional diluting system. While generally relying on gravity to drive water flow, as different amounts of toxicant and diluent are combined in glass or plexiglass mixing cells, they are almost always open to the surrounding atmosphere. In contrast, the system described here is based on a simple exposure design utilizing premixed stocks representing each exposure concentration. While the system is entirely closed to the surrounding atmosphere, for testing of volatile organic mixtures in addition to nonvolatile inorganic toxicants, the delivery manifold may be aerated for toxicants of low volatility and high BOD. The system incorporates flexible Teflon gas sampling bags for stock preparation and storage (thus avoiding need for a headspace), and digital unified-drive peristaltic pumps for controlled toxicant delivery. To reduce surface partitioning of toxicants, all system components are constructed of chemically inert materials (Teflon, glass and silicone). 相似文献
145.
Akiyo Tanaka Miyuki Hirata Makiko Nakano Masaharu Shiratani 《Thin solid films》2010,518(11):2934-1399
Due to the increased production of ITO, the potential health hazards arising from occupational exposure to this material have attracted much attention. This review consists of three parts: 1) toxic effects of indium compounds on animals, 2) toxic effects of indium compounds on humans, and 3) recommendations for preventing exposure to indium compounds in the workplace.Available data have indicated that insoluble form of indium compounds, such as ITO, indium arsenide (InAs) and indium phosphide (InP), can be toxic to animals. Furthermore, InP has demonstrated clear evidence of carcinogenic potential in long-term inhalation studies using experimental animals. As for the dangers to humans, some data are available concerning adverse health effects to workers who have been exposed to indium-containing particles. The Japan Society for Occupational Health recommended the value of 3 μg/L of indium in serum as the occupational exposure limit based on biological monitoring to preventing adverse health effects in workers resulting from occupational exposure to indium compounds. Accordingly, it is essential that much greater attention is focused on human exposure to indium compounds, and precautions against possible exposure to indium compounds are most important with regard to health management among indium-handling workers. 相似文献
146.
Nitrogen was supplied from two fast release sources, ammonium sulfate ((NH4)2SO4) and calcium nitrate (Ca(NO3)2) and a slow release source, isobutylidene diurea (IBDU) to boronia, a new flower crop native to Australia. At lower rates (25 kg per ha), N availability from different sources, as indicated by the leaf N concentration, did not differ within a month after application but three months after application, N availability was higher from IBDU than from (NH4)2SO4 or Ca(NO3)2. At 50 or 100 kg per ha, N availability was higher throughout the year from (NH4)2SO4 or Ca(NO3)2 than from IBDU, thereby allowing luxury consumption and causing toxicity. The flower yield increased with increasing N rates. Complete doses of all N rates which were applied early during the vegetative growth gave the highest yields and the same N rates applied in split doses at different phases of plant growth decreased the yields. In addition, high N availability during flowering (caused by a split dose) further decreased the yield. At all application times, IBDU gave the highest yield and the differences in yields with (NH4)2SO4 and Ca(NO3)2 were not significant. The leaf N concentration associated with maximum yield declined as the plant advanced towards flowering. 相似文献
147.
Sulfide inhibition of the methanogenic activity of granular sludge at various pH-levels 总被引:4,自引:0,他引:4
The effect of sulfide on the formation of methane from acetate in granular sludge originating from a UASB reactor has been determined using a new batch anaerobic toxicity assay. The assay is based on measurement of the methane concentration in the closed head space of a serum bottle, thus allowing operation at constant pH and without loss of sulfide via off-gases.
Sulfide toxicity appeared to be correlated with the free hydrogen sulfide concentration in the pH range 6.4–7.2. However this correlation did not hold at pH = 7.8–8.0. Free hydrogen sulfide concentrations leading to 50% inhibition were 250 mgS l−1 in the pH range 6.4–7.2 and 90 mgS l−1 at pH = 7.8–8.0.
The high tolerance for sulfide toxicity exhibited by the granular sludge can probably be attributed to the existence of a pH gradient in the sludge granules leading to an increased internal pH. 相似文献
148.
The number of species or variables in some designed environmental studies is too large for analysis using standard inferential statistics. To analyze the type of data, a two-stage procedure and follow-up methods are described. First, data are reduced using a measure of similarity or distance. Then, a permutation procedure is used to make inferences. Assuming the hypothesis is rejected, several follow-up analyses are presented as tools in understanding the causes of rejection. For example, to further understand treatment effects, a randomization based, multiple comparison procedure may be used; to better understand what differences the similarity or distance measure describes, a method based on removal of a species is given. The methods are illustrated on a study of the effects of zinc on the periphyton community in the New River, Va, U.S.A. 相似文献
149.
Dr. Ricardo Ferraz Prof. João Costa‐Rodrigues Prof. Maria H. Fernandes Dr. Miguel M. Santos Dr. Isabel M. Marrucho Prof. Luís Paulo N. Rebelo Prof. Cristina Prudêncio Prof. João Paulo Noronha Dr. Željko Petrovski Dr. Luís C. Branco 《ChemMedChem》2015,10(9):1480-1483
Significant antiproliferative effects against various tumor cell lines were observed with novel ampicillin salts as ionic liquids. The combination of anionic ampicillin with appropriate ammonium, imidazolium, phosphonium, and pyridinium cations yielded active pharmaceutical ingredient ionic liquids (API‐ILs) that show potent antiproliferative activities against five different human cancer cell lines: T47D (breast), PC3 (prostate), HepG2 (liver), MG63 (osteosarcoma), and RKO (colon). Some API‐ILs showed IC50 values between 5 and 42 nM , activities that stand in dramatic contrast to the negligible cytotoxic activity level shown by the ampicillin sodium salt. Moreover, very low cytotoxicity against two primary cell lines—skin (SF) and gingival fibroblasts (GF)—indicates that the majority of these API‐ILs are nontoxic to normal human cell lines. The most promising combination of antitumor activity and low toxicity toward healthy cells was observed for the 1‐hydroxyethyl‐3‐methylimidazolium–ampicillin pair ([C2OHMIM][Amp]), making this the most suitable lead API‐IL for future studies. 相似文献
150.
为了最大限度地降低矿山掘进巷道爆破作业中产生的大量烟尘,结合水炮泥抑尘降毒机理,以试验为基础,对不同配方的溶液进行表面张力、润湿能力及降毒性能的测定,得出水炮泥烟尘抑制剂最优配方为表面活性剂A_2、表面活性剂A_5、吸湿剂B_1、凝胶剂C_1、降毒剂D_1、降毒剂_E1,对应的质量浓度分别为0.1%、0.04%、0.5%、1%、0.03%及0.1%,此配方具有较低的表面张力,能快速润湿粉尘以及加速CO和氮氧化物的转化,从而提高掘进巷道爆破降烟尘效率。 相似文献