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811.
812.
Thecauseandmechanismoffluorideanomalyinkrill¥ZhangHaisheng;PanJianming;ChengXianhaoandLiuXiaoya(SecondInstituteofOceanography... 相似文献
813.
Degraded diesel oils are commonly used in marine power plants to conform to the demands of shipowners for fuel economy. The burning of these marine fuel oils, which frequently contain various extents of oxides of iron, silicon, calcium, vanadium and potassium, such as Na2SO4, Fe2O3, SiO2, CaO, V2O5, etc., are susceptible to form much more complex compounds of either gaseous or solid phases. The release of these emissions to the environment may cause atmospheric pollution and a health hazard to human beings. Emulsification of a fuel oil with water to produce a micro-water-particles-dispersed-in-oil (W/O) emulsion has been considered as one of the promising techniques to improve combustion characteristics of low-grade marine oils and in turn effectively help to reduce the release of air pollutants. Marine fuel oil A, which approximates ASTM No. 2D oil was used as the test oil and the surfactant Span 80 was used to promote the affinity and integrating force between the components of the emulsion. An emulsifying/homogenizing machine was employed to stir the emulsion mixture of the marine oil, distilled water, surfactant Span 80 and sodium sulfate (Na2SO4) powder of 300 ppm. The mechanically blended emulsion mixture was injected, atomized and burned in an oil-fired furnace using an automatic burner. Burning gas composition, burning efficiency and gas temperature were measured and analyzed. Compared to neat marine diesel oil, W/O emulsions had higher combustion efficiencies, higher concentrations of O2 and SO2, while gas temperatures were lowered and CO and NOx production was reduced. The addition of sodium sulfate decreased combustion efficiency and NOx concentration and increased O2, CO, and SO2 concentrations. 相似文献
814.
利用可视化编程语言VB开发出一套成像光谱仪资料处理系统,用于海面叶绿素浓度信息提取,具有操作方便的图形用户界面,大大简化了各种振兴中华,去了众多参数值的反复输入。图像处理模块可加入许多常用的图像处理功能。并可调入一些商业化软件,寿命完成许多图像处理功能。 相似文献
815.
In this paper the parameterizational approach of nonlinear source function and the implicit scheme of the model are discussed in detail. The matching problem is solved between time and space steps using the characteristics inlaid scheme with very strong physical meaning. The computational comparison in typical winds shows some improvements to the WAM model. That the hindcast results of the model for typhoon cases are in good agreement with real data illustrates its applicability to wave forecast and engineering study. 相似文献
816.
More attention has been paid to the research on decolorization of dyeing wastewater nowadays. In this study, an investigation
into the decolorization of dyeing wastewater was conducted using a combination of coagulant, carboxymethyl chitosan (NOCC)
and coagulant aid, polyscrylamide (PAM). The factors influencing the decolorization efficiency, such as pH value, coagulant
and the dosages of coagulant, were discussed. The results showed that using PAM as coagulant aid could reach a high decolorization
efficiency compared with using NOCC alone. The optimal conditions were pH 2.3, 480 mg/L for NOCC, and 4–8 mg/L for PAM. Under
the optimum conditions, the rate of decolorization could achieve 99%, and the removal of chemical oxygen demand (COD) could
achieve 90%. In addition, the membrane processes with chitosan/rare-earth-metals could enhance the decolorization rate of
Direct Black FF to 94.7%, and Indanthren Red F3B to 98.2%, respectively. Key words - Carboxymethyl chitosan, PAM, Dyeing wastewater,
Decolorization, Chitosan/rare-earth membrane 相似文献
817.
The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study andstatistic analyses, the epidemiological study was carried out on the disease and death in juvenile popula-tions of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A,B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farmof Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province fromNovember 1993 to April 1995. The results show that the deaths which occurred in juvenile populations of Pinctada maxima pre-sented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearloyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean bodylengths of juvenile populations show that the mortality rate become higher under 4 cm of mean bodylengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak ofmortality rate occurred in 1 ~3 cm of mean body lengths. The results of histological observation showedthat rickettsia-like organism inclusions were common, histological widespread infective agent among ev-ery batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rick-ettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile popula-tions. After or within every peaks of RLO infection were all accompanied with the peaks of mortalityrates of host populations and the mortality rates declined with decreased RLO infection. So the evidencesof histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO)may be as an important pathogenic organism of disease and death of cultured Pinctada maxima. In addi-tion, a few ciliates were discovered only in part of batch A of cultured juvenile population. The mortalityrates in juvenile populations were not correlated with the weekly mean temperature and salinity of seawater. 相似文献
818.
弧菌病是海水网箱养殖石斑鱼Epinephelus主要疾病之一。本文利用致病菌──创伤弧菌Vibriovulnificus强毒菌株制备出安全性很高的福尔马林灭活疫苗(FV)和热灭活疫苗(HV)。这两种疫苗无论使用佐剂与否,通过肌肉注射接种青石斑鱼E.awoara都能使鱼体在较短时间内产生较强的体液免疫应答,而且抗体效价能维持较长时期。免疫后的青石斑鱼获得了良好的免疫保护力。 相似文献
819.
本文对1763~1987年间历次强、中、弱El Nio事件的发生频率、各次事件的间隔年数,以及当某类强度事件发生后下一次事件的强度级别与发生时间的概率等做了统计分析。结果表明,El Ni(?)o事件的长期变化具有一定的规律性。这些规律可作为预测El Ni(?)o事件的参考。 相似文献
820.
本文用计算确定双拖网曳纲的空间形状与张力,估算在一定拖速下两船间距、水深与网具水平扩张的关系。根据模型试验测出的水平与垂直扩张值,换算出双拖网网口高度并与实测结果比较。可针对各级渔轮和生产条件,广泛计算并列出图表,以便在生产中用于双拖网调整。 相似文献