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31.
杀虫单降解菌的筛选分离与降解特性研究 总被引:8,自引:0,他引:8
从农药厂废水排放沟污泥中分离到一株对杀虫单有较强降解能力的菌株LY-4,经鉴定为巨大芽孢杆菌(Bacillus megaterium)。其生长的最适pH为7,最适温度为30℃。该菌对杀虫单有很强的耐受性,在杀虫单浓度ρ=5000mg/L时,仍能较好地生长并发挥降解作用。当杀虫单初始浓度高于一定值时,一定量的菌剂对杀虫单的降解率随底物浓度的提高而降低,而绝对去除量则随底物浓度的提高而提高。与不加菌的对照相比,加入LY-4后,可使杀虫单浓度在很短的时间内降到很低的水平。图5表1参6 相似文献
32.
Gradients of genetic distances (GGDs) between 26 adjacent cenopopulations of Scotch pine (Pinus sylvestris L.) along the transects through the distinct landscape-ecotopic isolation borders were analyzed graphically. The results
made it possible to reveal and quantitatively estimate gradients and borders of gene-pool structural patterns in populations
of this species in the central part of Northern Eurasia. In lowland areas, the most distinct borders were found between pine
populations growing on dry lands and bogs (Pineta sphagnosa) in the forest zone of the Transural region, as well as between the Arakaragaiskii and Amankaragaiskii island pine forests
in the steppe zone (Northern Turgai). In highland areas (the Urals and the Carpathians), the greatest GGDs were observed between
low-mountain (about 600 m above sea level) and middle-mountain (850–900 m) populations. Analysis of GGDs is a promising gene-geographic
method for determining population borders and studying the chorogenetic structure of species. 相似文献
33.
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35.
From 35 therapeutic abortions performed because rubella had occurred at 2–19 weeks of pregnancy, 120 fetal organs, 12 specimens of mixed products of conception, and 15 placentae were tested for rubella virus. Virus was isolated from 10 out of 11 fetuses (91 per cent) from women infected at 2–8 weeks, from 5 out of 8 (63 per cent) infected at 9–10 weeks, and from 2 out of 16 (13 per cent) infected at 11–19 weeks. Hybridization tests for viral RNA on 39 fetal organs from eight cases revealed infection in four additional fetuses. Virus was isolated from only 3 out of 15 aborted placentae, but hybridization tests on six placentae revealed infection in three additional specimens. Hybridization was superior to virus isolation for detecting rubella infection in products of conception and is therefore potentially the better method for examining chorionic villus biopsies. Rubella virus was isolated from the throats of 4 out of 9 infants (44 per cent) infected during the first 12 weeks of gestation, but from none of 13 infected after 17 weeks. Infants in the latter group are unlikely to infect susceptible contacts. 相似文献
36.
X. Fu J. Tabata T. Takanashi S. Ohno S. Tatsuki Y. Ishikawa Y. Huang H. Honda 《Chemoecology》2004,14(3-4):175-180
Summary. The sex pheromone of Ostrinia orientalis
(Lepidoptera: Crambidae) was analyzed by gas chromatography–electroantennographic detection (GC–EAD), GC–mass spectrometry and a series of bioassays. Three EAD-active
compounds were detected in the female sex pheromone
gland extract, and identified as tetradecyl acetate (14:OAc),
(Z)-11-tetradecenyl acetate (Z11-14:OAc) and (E)-11-tetradecenyl acetate (E11-14:OAc). The titers (ratio) of 14:OAc, Z11-14:OAc and
E11-14:OAc in 3-day-old virgin
females were 0.49 ng (10), 4.86 ng (98) and 0.10 ng (2),
respectively. In a wind-tunnel bioassay, the 98:2 blend of
Z11- and E11-14:OAc, but not Z11-14:OAc alone, elicited
the same male behavioral responses as virgin females and
crude gland extracts. 14:OAc was inactive by itself, and did
not show any synergistic effect on the binary blend.
Field trapping experiments also confirmed the attractiveness
of the binary blend to O. orientalis
males. Based on
these results, we concluded that the sex pheromone of
O. orientalis
is a 98:2 mixture of Z11-14:OAc and
E11-14:OAc. This sex pheromone is very similar to that of the Z-type European corn borer,
O. nubilalis. The present
finding raises the question of whether O. orientalis
, which is indistinguishable from O. nubilalis
based on external morphology,
is a biologically distinct species independent from
O. nubilalis. 相似文献
37.
We describe here a new type of method for isolation of rare cell populations in biological fluids. The method is based on the anthraquinone technology for covalent binding of molecules to a polymer surface. An anthraquinone molecule conjugated via a linker to an electrophilic group (AQ Immobilizer™ reagent, Exiqon A/S) is covalently bound to a polymer surface by UV irradiation. The electrophilic group of this AQ reagent can covalently bind a specific antibody directed against a specific cell marker. Applying a cell sample to the functional surface, the cells having the specific cell marker on the cell surface will bind to the antibody on the functional surface. Using this technique, even extremely small cell populations may be isolated. We succeeded in isolating fetal cells from maternal blood samples in the first trimester for chromosome defects genetic diagnosis. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
38.
高效复合菌在木薯酒精废液处理中的应用研究 总被引:1,自引:0,他引:1
对酒精废液生物处理反应器内颗粒污泥中的微生物进行分离纯化.分离出的8株高效优势菌,初步鉴定结果:1号为皮杆菌属;2号为棒杆菌属;3号、4号为微小杆菌属;5号为乳杆菌属;6号为纤维单胞菌属;7号为丙酸杆菌属;8号为红长命菌属.对8种纯化后的菌株进行混合培养,确定了复合菌群生长最佳培养温度为37℃,最适pH值为6.8.在处理过程中投加适量葡萄糖、硝酸铵和微量元素能够提高复合菌群的处理效果.最佳添加量为:葡萄糖0.5g/L,硝酸铵1g/L,Fe2 5mg/L和Ca2 25mg/L.在日处理量100 m3的UASB生物反应器中投加该复合菌群后,木薯酒精废液的COD去除率明显提高,达到90%以上.处理系统运行稳定. 相似文献
39.
Leakage diagnosis of hydrocarbon pipelines can prevent environmental and financial losses. This work proposes a novel method that not only detects the occurrence of a leakage fault, but also suggests its location and severity. The OLGA software is employed to provide the pipeline inlet pressure and outlet flow rates as the training data for the Fault Detection and Isolation (FDI) system. The FDI system is comprised of a Multi-Layer Perceptron Neural Network (MLPNN) classifier with various feature extraction methods including the statistical techniques, wavelet transform, and a fusion of both methods. Once different leakage scenarios are considered and the preprocessing methods are done, the proposed FDI system is applied to a 20-km pipeline in southern Iran (Goldkari-Binak pipeline) and a promising severity and location detectability (a correct classification rate of 92%) and a low False Alarm Rate (FAR) were achieved. 相似文献
40.
苏云金芽胞杆菌(Bacillus thuringiensis)几丁质酶的分离纯化及酶学性质 总被引:7,自引:2,他引:7
以苏云金芽胞杆菌为材料 ,通过硫酸铵沉淀分级分离、DEAE - 32离子交换柱层析初步纯化 ,获得比活力为15 0 .5Umg-1的酶制剂 .研究酶催化胶体几丁质水解的反应时间和酶量对酶活力的关系 ,探讨酶催化胶体几丁质的最适条件 .温度和 pH对酶活力的影响和酶的热稳定性及酸碱稳定性的结果表明 :酶催化胶体几丁质水解的的最适pH为 5 .6、最适温度为 5 8℃ .该酶在pH 4 .5~ 6 .5区域稳定 ,而在pH >8能很快失活 ;在 5 5℃以下处理 30min ,酶活力保持不变 ;高于 5 5℃ ,酶快速失活 .图 5参 11 相似文献