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991.
992.
A comparative analysis of spatial population structure in the northern red-backed vole (Clethrionomys rutilus Pall.) and large-toothed red-backed vole (Cl. rufocanus Sund.) has been performed in the middle taiga zone of the Middle Irtysh region (Omsk oblast). Populations of these species are represented by sets of territorial groups whose numbers and spatial distribution change from year to year depending on the ratio of these species in a biotope and their population density. There is no significant interspecific competition between cohabitant Cl. rutilus and Cl. rufocanus. In particular, this follows from the fact that the population density and distribution pattern of one species are independent of those of the other species. It has been found that the size of home ranges in Cl. rutilus inversely depends on its population density, with that in Cl. rufocanus remaining approximately the same at different population densities, and that the structure of the resident part of the population in both species changes during the season, as voles from neighboring habitats or dispersing voles settle in the study area. 相似文献
993.
D. D. Gabaev 《Russian Journal of Ecology》2007,38(2):112-118
Conditions for reproduction of the red king crab Paralithodes camtschatica (Tilesius) on scallop plantations in Primorye have been studied. It has been found that the settling of larvae and the growth of juveniles to the size sufficient for their survival take place only in the cleanest water areas of Peter the Great Bay. Solar activity (expressed as the Wolfer number) is one of the most important abiotic factors affecting P. camtschatica reproduction. The population dynamics of juvenile crabs are characterized by fluctuations with two-year and five-year cycles. 相似文献
994.
E. A. Artem’eva 《Russian Journal of Ecology》2007,38(1):58-67
Phenotypic diversity in populations of Polyommatus icarus Rott. (Lepidoptera, Lycaenidae) is regarded as a component of the ecocenotic strategy of the species, trends in which may serve as markers characterizing the state of natural populations. 相似文献
995.
This study explored the removal of five veterinary pharmaceuticals (VPs) (sulfamethoxazole (SMETOX), trimethoprim (TMP),
ciprofloxacin (CIPRO), dexamethasone (DEXA) and febantel (FEBA)) from different water matrices (Milli-Q water, model water, tap
water and real pharmaceutical wastewater using four types of nanofiltration (NF) membranes (NF90, NF270, NF and HL) and two
reverse osmosis (RO) membranes (LFC-1 and XLE). All VPs were added to different water matrices at a concentration of 10 mg/L.
Rejections of VPs and water flux were measured. The rejection increased with increase of molecular weight. The highest rejections
were obtained with RO membranes (LFC-1, XLE) and tight NF (NF90) membrane. In general, the rejection of VPs was higher in
model water and tap water than in Milli-Q water, but the water flux was lower. This was mainly explained by ion adsorption inside the
membranes pores. Narrower pore size counteracted the effect of presence of low concentration of natural organic matter (NOM) in tap
water. The NOM was assumed to enhance the adsorption of VPs onto membrane surface, increased the size exclusion and electrostatic
repulsion also appeared during the transport. Investigated water matrices had influence on water flux decline due to their complexity. 相似文献
996.
997.
The hazardous chemicals maritime transportation system (HCMTS) belongs to a typical complex tech-social system, which is comprised of multiple functions with interactions. To quantitatively assess the risks triggered by failure coupling links (CLs) between upstream and downstream functions, a hybrid method integrating the Functional Resonance Analysis Method (FRAM), fuzzy set theory, and risk matrix is proposed in the present study. A total of 10 essential functions and 16 CLs involved in HCMTS were identified by FRAM. The fuzzy set theory was adopted to aggregate the weights of risk consequence and likelihood for CLs. A risk matrix with a continuous scale was utilized to assess and rank the CLs’ risks. The results have been demonstrated by the comparisons, indicated that the risk indexes (RIs) of the CLs between the functions < Consignment of HCs> and <Undertaking the transportation>, <Consignment of HCs> and <Declaration of HCs>, <Loading HCs in port> and <Ship navigation at sea > are higher in the whole chain of HCMTS. 相似文献
998.
999.
以环氧树脂基聚合物膜为萃取相,在电场作用下富集目标物,与高效液相色谱(HPLC)联用,应用于环境水样中硝基苯污染物的测定.考察了电压大小、萃取时间、洗脱时间、离子强度和溶液pH值对电增强萃取效率的影响.实验结果表明,环氧树脂基聚合物膜的萃取量与膜上所施加的控制电位相关,阴极极化时,膜对硝基苯的萃取量增大;在阳极极化时,膜萃取量减小.在电压为-0.3kV,硝基苯溶液pH=4的条件下,萃取20min,得到该方法的检出限为0.015μg·mL-1,在0.05~3.0μg·mL-1范围内具有良好的线性关系,可决系数为0.9929,变异系数小于5%.用上述方法分析鱼塘水,硝基苯3种不同加标水平的回收率为79.8%~108.2%.结果表明,该方法既可用于环境水样品中的硝基苯去除又可用于检测. 相似文献
1000.
不同混凝剂对污泥脱水性能的影响研究 总被引:11,自引:3,他引:8
采用无机和有机混凝剂对污泥进行调理,通过测定污泥比阻、Zeta电位以及污泥上清液中蛋白质、多糖和DNA含量,同时结合污泥上清液的三维荧光光谱分析,研究了不同混凝剂及其投加量对污泥脱水性能的影响.结果表明:当聚合氯化铝(PAC)、高效聚合氯化铝(HPAC)和氯化铁(FeCl3)的投加量在干污泥量的10%附近时,污泥比阻值最小,同时三维荧光强度值也最小,Zeta电位以及上清液中蛋白质、多糖和DNA的含量基本趋于稳定.无机混凝剂与有机混凝剂联合作用调理污泥后其脱水效果明显优于单一混凝剂调理.有机混凝剂与无机混凝剂投加顺序对污泥脱水性能影响显著,先投加无机混凝剂再投加有机混凝剂的脱水效果最佳,研究筛选出两种混凝剂联合作用调理污泥后,其脱水效果顺序为10%PAC+0.5%PAM>10%FeCl3+0.5%PAM>10%HPAC+0.5%PAM. 相似文献