排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
根据南通市2016和2017年冬季大气多参数站自动监测PM2.5数据和在线离子色谱分析仪Marga监测的PM2.5中水溶性离子数据,分析了南通市冬季PM2.5中水溶性离子污染特征。结果表明,南通市2016和2017年冬季,ρ(PM2.5)分别为58和54μg/m 3,均高出其年均值(14μg/m^3);ρ(水溶性离子)总占ρ(PM2.5)百分比分别为74.5%和74.3%;二次离子ρ(NO3^-、SO4^2-和NH4^+)占ρ(PM2.5)百分比分别为66.8%和66.6%;各水溶性离子占比大小依次为:NO3^-、SO4^2-、NH4^+、Cl^-、K^+、Na^+、Ca^2+、Mg^2+。对ρ(NO3^-)/ρ(SO 4^2-)分析表明,移动源已经成为南通市冬季的主要污染源,且呈逐年增强趋势。对氯氧化率和硫氧化率的分析表明,南通市冬季存在较明显的二次污染,SO2的转化程度大于NO2。除Na^+和Mg^2+外,其他离子与PM2.5均呈显著相关性,NO3^-、SO4^2-与NH4^+之间的相关系数最高,Cl^-与除Na^+外的所有阳离子均呈显著相关性。 相似文献
2.
有机污水磁处理实验研究 总被引:9,自引:0,他引:9
本文选择城镇生活污水与造纸废水、印染废水、橡胶业废水等几种典型工业废水以及医院污水为对象进行磁处理实验研究。结果表明有机污废水经磁处理以后,其COD指标都有不同程度的降低,由于成分不同,COD降幅不同,同时COD最大降幅所处的最佳磁强也不同。 相似文献
3.
UASBAF工艺在龙涤集团废水处理中的应用 总被引:2,自引:0,他引:2
采用厌氧污泥床过滤器(UASBAF)处理龙涤集团高浓度涤纶废水,经过设计参数选择,工程设计和运行效果分析。运行结果证明,UASBAF厌氧池的容积负荷为9.2kgCOD/m 3·d,COD去除率80% ,接触氧化池的COD去除率95% 左右,处理效果稳定,基本达到设计要求。 相似文献
4.
Unlike other birds, shiny cowbirds (Molothrus bonariensis) must locate host nests where to lay their eggs and then decide whether to parasitise them. They should also synchronise their laying with that of the host to increase the survival of parasite egg and young. Shiny cowbirds can discover nests using host behaviour as a cue, or by searching the habitat without need for the presence of a host. Besides, they can synchronise parasitism with host laying by monitoring nests during building and laying, or directly by assessing the degree of development of embryos through the puncture of host eggs. Alternatively, synchronization can arise by lower nest attentiveness during host laying. We determined the extent of synchronization between laying of shiny cowbirds and chalk-browed mockingbirds (Mimus saturninus) and estimated if parasitism was negatively associated with host nest attentiveness. We also conducted an experiment to test if host activity was necessary to locate nests, and if puncture of host eggs was a cue for deciding parasitism. Shiny cowbirds synchronised parasitism with host laying in 75% of the cases and synchronization was not explained by lower host nest attentiveness during laying. Shiny cowbirds located nests without need for presence of a host, but the decision of parasitising the nest depended on host activity at the nest. The information that shiny cowbirds could obtain through egg punctures was not necessary for deciding parasitism. Our results indicate that shiny cowbirds rely on the precise timing of their eggs and avoid laying in unsuitable nests. 相似文献
5.
6.
Bettina Mahler Viviana A. Confalonieri Irby J. Lovette Juan C. Reboreda 《Behavioral ecology and sociobiology》2008,62(7):1193-1199
For avian brood parasites in which individual females are host-specialists, the arms race between hosts and parasites has
favored egg color polymorphism in the parasite, with female lineages laying mimetic eggs that resemble those of the host species
they parasitize. Female sex-linked inheritance of egg color fosters evolutionary stability of egg polymorphism if female lineages
show both consistent eggshell color and host use. This co-evolutionary relationship is unlikely to occur if individual brood
parasites use different hosts or if egg color is not maternally inherited. The shiny cowbird (Molothrus bonariensis) is an extreme generalist brood parasite that shows a very high degree of egg polymorphism. We tested whether egg spotting
in this species has female sex-linked inheritance. If genetic factors controlling the expression of egg spotting were present
on the female-specific W chromosome, we expected co-segregation between spotting patterns and mtDNA haplotypes, as both W
and mtDNA are maternally inherited. In contrast to the known maternal inheritance of spotting patterns in great tits, we found
no associations between eggshell spotting and mtDNA haplotypes, which suggests that eggshell spotting is not maternally inherited
in this cowbird species. 相似文献
7.
Bettina Mahler Yanina Sarquis Adamson Alejandro G. Di Giacomo Viviana A. Confalonieri Juan C. Reboreda 《Behavioral ecology and sociobiology》2009,63(11):1603-1608
The screaming cowbird Molothrus rufoaxillaris has been long known as a host specialist brood parasite. However, in the past years, the utilization of two new hosts has
been documented. We examined the variation in mitochondrial control region sequences from screaming cowbird chicks found in
the nests of two hosts, the bay-winged cowbird (Agelaioides badius), which is its regular host, and the chopi blackbird (Gnorimopsar chopi), which is a new host, in Formosa Province, Argentina. If a group of females switched to this new host, we expected to find
an association between host use and haplotype frequency distribution, indicating the presence of host-specific female lineages,
whereas we expected no such association if the cowbird population incorporated this new host and females use both hosts simultaneously.
Haplotype frequency distributions differed between cowbird chicks from the nests of both hosts. This indicates that nest choice
by females of this brood parasite is not random and that they preferentially parasitize the nests of the same host species. 相似文献
8.
Costs of brood parasitism and the lack of defenses on the yellow-winged blackbird - shiny cowbird system 总被引:2,自引:0,他引:2
The shiny cowbird (Molothrus bonariensis) is a generalist brood parasite that lays either white-immaculate or spotted egg morphs in eastern Argentina and Uruguay.
Some hosts accept both morphs, others accept spotted eggs and reject the white morph, but no host has been found to accept
white eggs and reject spotted ones. It has been suggested that the yellow-winged blackbird (Agelaius thilius) may be that type of host. The finding of a white acceptor-spotted rejector species would help to explain the occurrence
and maintenance of the parasite egg polymorphism. We studied the incidence of shiny cowbird parasitism on this host, its costs
for their reproductive success and the presence of antiparasitic defenses in the yellow-winged blackbird - shiny cowbird system.
The parasite affected the reproductive success of the host in two ways. Cowbirds punctured host eggs causing a reduction in
clutch size, and yellow-winged blackbirds deserted their nests whenever they suffered high egg loss. In addition, parasitized
nests suffered higher predation during the nestling stage, but not during egg stages, indicating that the difference found
was related to the presence of the cowbird chick, and not to higher exposure of parasitized nests to both parasites␣and predators.
Despite the costs imposed by the parasite, yellow-winged blackbirds have not evolved antiparasitic defenses. This host did
not reject any egg morph of the shiny cowbird nor desert parasitized nests unless it had suffered high egg loss. Current explanations
for the host lack of defenses, the “time lag” and the “equilibrium” hypothesis, are discussed.
Received: 29 August 1997 / Accepted after revision: 10 January 1998 相似文献
9.
生物活性炭纤维(BACF)是在生物活性炭的基础上,以活性炭纤维代替颗粒活性炭,用于处理微污染水中有机污染物。BACF技术作为一种新的水的深度处理工艺,结合了吸附与生物降解的双重效能,可以有效提高对原水的净化效果,同时也可以扩大水源水的取水范围,是一项先进的水处理技术。 相似文献
10.
气相色谱法测定废水中的氯化苄 总被引:5,自引:0,他引:5
用苯萃取废水中的氯化苄,经毛细管柱GC/FID测定,以保留时间定性,峰高定量。本法具有快速、灵敏和较好的精密度与准确度等优点。氯化苄平均浓度为2.29~10.79 m g/L时,其相对偏差在2.1% ~3.8% 之间,CV在4.1% ~6.4% 之间,标准差在0.03~0.2 m g 之间,标准曲线的相关系数为0.999。 相似文献