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181.
182.
色彩心理与城市交通安全文化分析 总被引:1,自引:0,他引:1
城市交通采用什么色彩更适宜,是一个交通安全文化与色彩设计和谐的问题。为防止或减少因交通色彩无秩序、不和谐、无标准而导致的交通事故,对交通、色彩、环境与人这一复杂系统当中色彩作用于人的心理而引起的感性及生理上的反应与交通色彩安全问题做了分析,阐述了色彩心理效应对交通安全文化的要求,提出了控制对策,为今后城市交通安全色彩设计提供了基础研究。 相似文献
183.
在磷酸介质中,Mn(Ⅱ)存在下,DAoPM和铬(Ⅵ)反应生成橙色物,λmax=480nm、ε=2.25*10^5L.mol^-1.cm^-1,铬(Ⅵ)含量在0-5μg/25mL内符合比尔定律,方法用于水样中铬(Ⅵ)的测定,结果满意。 相似文献
184.
185.
常温UASB装置设计与运行控制 总被引:1,自引:0,他引:1
五粮液集团白酒生产销售居全国同行业之首,根据白酒生产的工艺技术和水质特性选择UASB-UBF-SRB工艺处理,运行效果达到国家规定的排放标准,文章着重介绍五粮液集团某车间废水处理站厌氧处理系统四季中各种参数的协调运行控制。 相似文献
186.
为了实现钢材酸洗废液的资源化,能够同时回收盐酸和铁盐,提出了加盐蒸馏回收盐酸与蒸馏母液制备聚铁混凝剂两段组合工艺相结合的技术.实验对质量浓度为9.28%的实际盐酸废液进行了研究,考察了添加盐的种类、盐的投加量和蒸馏量等因素对再生盐酸回收效果和聚铁混凝剂溶液混凝效果的影响.研究表明,氯盐可以明显改变氯化氢、水的相对挥发度,当CaCl2投加量为1 mol/L,体积蒸馏量在30%时,为此工艺的最佳条件.在此工艺条件下,再生盐酸质量浓度约22.3%;蒸馏母液制备得到的聚铁混凝剂溶液应用实验表明,对印染废水脱色效果良好.此工艺不仅实现了酸洗废液中残酸和铁离子的资源化利用,而且达到酸洗废液的零排放. 相似文献
187.
Characteristics of high-sulfate wastewater treatment by two-phase anaerobic digestion process with Jet-loop anaerobic fluidized bed 总被引:2,自引:0,他引:2
A new anaerobic reactor, Jet-loop anaerobic fluidized bed (JLAFB), was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed (AFB) reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids (VFA) in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/(m^3.d), the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found. 相似文献
188.
Rebecca J. Safran 《Behavioral ecology and sociobiology》2007,61(9):1359-1368
In most avian species, individuals are faced with two critical decisions at the start of a breeding season: choosing a breeding
site and a mate. An analysis of these decisions in light of population-level patterns, such as group size variation in social
breeders, can illuminate the causes and patterns of habitat selection behavior. Group sizes are variable in barn swallows;
however, no clear and consistent benefits of group breeding have been found in this species, and it is puzzling as to why
individuals breed socially. Previous analyses demonstrated that individuals aggregate to gain access to nests that were constructed
during previous seasons; however extra-pair matings are also prevalent in this species, raising questions about the mate-selection
strategies of females across different group sizes. In this paper, I address the question of how females make their first
site-selection decisions in terms of two features known to be causally related to seasonal reproductive success: (1) colorful
males or (2) old nests. Using experimental and observational data, I tested, but found no support for, the hypotheses that
propose female settlement decisions are a function of (1) the prevalence of colorful males or (2) the increased opportunity
for extra-pair matings at group sites. Instead, it is apparent that female settlement patterns are strongly tied to the availability
of old nests at a site. Extra-pair fertilizations are equally common across all group sizes in this population, suggesting
that females do not face a trade-off between old nests and the possibility of extra-pair mating decisions when making settlement
decisions. 相似文献
189.
Mapping Invasive Aquatic Vegetation in the Sacramento-San Joaquin Delta using Hyperspectral Imagery 总被引:5,自引:0,他引:5
Underwood EC Mulitsch MJ Greenberg JA Whiting ML Ustin SL Kefauver SC 《Environmental monitoring and assessment》2006,121(1-3):47-64
The ecological and economic impacts associated with invasive species are of critical concern to land managers. The ability to map the extent and severity of invasions would be a valuable contribution to management decisions relating to control and monitoring efforts. We investigated the use of hyperspectral imagery for mapping invasive aquatic plant species in the Sacramento-San Joaquin Delta in the Central Valley of California, at two spatial scales. Sixty-four flightlines of HyMap hyperspectral imagery were acquired over the study region covering an area of 2,139 km2 and field work was conducted to acquire GPS locations of target invasive species. We used spectral mixture analysis to classify two target invasive species; Brazilian waterweed (Egeria densa), a submerged invasive, and water hyacinth (Eichhornia crassipes), a floating emergent invasive. At the relatively fine spatial scale for five sites within the Delta (average size 51 ha) average classification accuracies were 93% for Brazilian waterweed and 73% for water hyacinth. However, at the coarser, Delta-wide scale (177,000 ha) these accuracy results were 29% for Brazilian waterweed and 65% for water hyacinth. The difference in accuracy is likely accounted for by the broad range in water turbidity and tide heights encountered across the Delta. These findings illustrate that hyperspectral imagery is a promising tool for discriminating target invasive species within the Sacramento-San Joaquin Delta waterways although more work is needed to develop classification tools that function under changing environmental conditions. 相似文献
190.