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71.
Two‐dimensional model of diffusion processes around a river mouth   总被引:1,自引:1,他引:0  
The steady state diffusion equation is solved for two‐dimensional flow around a point source along an infinite straight boundary. Solutions obtained are related to the observed distribution of temperature and salinity around the mouth of the Buller River, South Island, New Zealand.  相似文献   
72.
A method for ploidy verification of triploid and diploid Haliotis midae was developed using molecular microsatellite markers. In all, 30 microsatellite loci were tested in control populations. A final micro satellite multiplex consisting of seven markers were optimised and a complete protocol is reported. This protocol was successfully applied in identifying the ploidy levels of 42 ploidy-unknown abalone, showing the utility of microsatellite markers as tools for verifying the ploidy of individual abalone. The protocol can be applied in larger animals for which the isolation of nuclei and metaphase chromosomes from tissues is difficult.  相似文献   
73.
In the present work, biosorption of Cr(VI) by Nymphaea rubra was investigated in batch studies. Batch experiments were conducted to study the effect of initial sorbent dosage, solution pH and initial Cr(VI) concentration. The results showed that the equilibrium uptake capacity was increased with decrease in biomass dosage. The Cr(VI) removal was influenced by the initial chromium compound concentration. Langmuir and Freundlich adsorption isotherm models were used to represent the equilibrium data. The Freundlich isotherm model was fitted very well with the equilibrium data when compared to Langmuir isotherm model. The sorption results were analyzed for pseudo‐first order and pseudo‐second order kinetic model. It was observed that the kinetic data fitted very well with the pseudo‐second order rate equation when compared to the pseudo‐first order rate equation. Fourier transform infrared spectrum showed the presence of different functional groups in the biomass. The surface morphology of the sorbent was exemplified by SEM analysis. Aquatic weeds seem to be a promising biosorbent for the removal of chromium ions from water environment. This paper reports the research findings of a laboratory‐based study on the removal of Cr(VI) from the synthetic solution using the dried stem of N. rubra as a biosorbent.  相似文献   
74.
Nymphaea rubra stem was used as a low cost and easily available biosorbent for the removal of Reactive Red 2 dye from an aqueous solution. Initially, the effects of biosorbent dosage (0.2–1.0 g L–1), pH (1–6), and dye concentration (30–110 mg L–1) on dye removal were studied. Batch experiments were carried out for biosorption kinetics and isotherm studies. The results showed that dye uptake capacity was found to increase with a decrease in biosorbent dosage. Equilibrium uptake capacity was found to be greatest at a pH value of 2.0, when compared to all other pH values studied. The equilibrium biosorption isotherms were analyzed by the Freundlich and Langmuir models. The equilibrium data was found to fit very well with the Freundlich isotherm model when compared to the Langmuir isotherm model. The kinetic data was analyzed using pseudo-first order and pseudo-second order kinetic models. From the results, it was observed that the kinetic data was found to fit the pseudo-second order kinetic model very well. The surface morphology of the stem of the N. rubra biosorbent was exemplified by scanning electron microscopy. Fourier transform infrared analysis was employed to confirm the existence of an amine group in the stem of N. rubra.  相似文献   
75.
皱纹盘鲍多糖抗肿瘤药理作用研究   总被引:3,自引:0,他引:3  
对从软体动物皱纹盘鲍HaliotisdiscushannaiIno中分离提取的纯多糖进行了抗肿瘤活性研究。药理实验表明,多糖对体外培养的小鼠移植性肿瘤肉瘤S180、肝癌HepA细胞无细胞毒作用,但能明显延长HepA小鼠的生存时间,抑制小鼠移植性肉瘤S180的生长;在抑瘤的同时,能明显提高免疫器官胸腺、脾脏的重量,降低荷瘤小鼠肝脏中过氧化脂质的水平。提示鲍鱼多糖可能是通过增强荷瘤小鼠的免疫功能和抗氧化作用而发挥其抗肿瘤活性的  相似文献   
76.
An experiment was performed to determine the dietary phosphorus requirement of the young abalone,Haliotis discus hannai. Five semi-purified diets were formulated to provide a series of graded levels of dietary total phosphorus (0.23%–1.98) from monobasic potassium phosphate (KH2P04). The brown alga,Laminaria japonica, was used as a control diet. Similar size abalone were distributed in a single-pass, flow-through system using a completely randomized design with six treatments and three replicates each treatment. The abalone were hand-fed to satiation with appropriate diets in excess, once daily at 17:00. The feeding trial was run for 120-d. Survival rate and soft-body to shell ratio (SB/S) were constantly maintained regardless of dietary treatment. However, the weight gain rate (WGR), daily increment in shell length (DISL), muscle RNA to DNA ratio (RNA/DNA), carcass levels of lipid and protein, soft-body alkaline phosphatase (SBAKP), and phosphorus concentrations of whole body (WB) and soft body (SB) were significantly (ANOVA, P<0.05) affected by the dietary phosphorus level. The dietary phosphorus requirements of the abalone were evaluated from the WGR, DISL, and RNA/DNA ratio respectively, by using second-order polynomial regression analysis. Based on these criteria, about 1.0%–1.2% total dietary phosphorus, i.e. 0.9%–1.1% dietary available phosphorus is recommended for the maximum growth of the abalone. Project 39670572 supported by the NSFC.  相似文献   
77.
鲍育苗期病害的防治研究──Ⅰ.福尔马林的防治试验   总被引:1,自引:0,他引:1  
在皱纹盘鲍HaliotisdiscusHannai育苗期间,幼鲍用福尔马林药浴,对原生动物、线虫、桡足类等引起的病害防治有显著效果。当浓度为5~20g/m3,浸浴6~12h能杀死附着板上的原生动物、线虫和部分桡足类,同时也有强的杀菌作用,而对幼鲍及饵料硅藻的发育和活力均没影响。  相似文献   
78.
皱纹盘鲍主要器官的亚显微结构   总被引:2,自引:0,他引:2  
对皱纹盘鲍的胃、直肠、消化腺、肾、鳃、心脏、外套膜、足等器官的亚显微结构进行了研究。结果表明 :(1 )各消化器官的组织结构中富含酶原颗粒和分泌颗粒 ,这些颗粒具有消化和抗病的功能 ;(2 )鳃和心肌的组织结构中富含线粒体 ,这与其活动量大密切相关 ;(3 )外套膜的组织结构中富含分泌颗粒 ,这些颗粒物质参与贝壳的形成和体液免疫 ;(4)肾实质中静脉呈网状分布 ,这与体液的有效过滤有关 ;(5 )腹足的肌纤维成束 ,并形成三维的网状结构 ,以适应匍匐与吸附的生活方式  相似文献   
79.
维生素E对皱纹盘鲍幼鲍生长、存活及体成分的影响   总被引:8,自引:3,他引:8  
于1997年5月在山东荣成石岛鲍珍品养殖场采集幼鲍,采用单因素试验方法进行幼鲍维生素E(VE)营养需要的研究。以酷蛋白和明胶为蛋白源,通过用不同浓度VE的饲料(E1-E7七个实验组),即在每100g饲料中分别添加0、5、10、20、50、100、200mgVE来饲喂幼鲍(平均体重为220-240mg)103天。结果表明,饲料中适量的VE具有促进幼鲍生长的作用;幼鲍软体部水分和脂肪含量不受饲料中VE添加水平的影响,然而饲料中VE添加水平显著影响软体部蛋白质含量;贝壳中灰分和钙、磷含量不受VE添加水平的影响。以增重和蛋白质增量为指标,皱纹盘鲍幼鲍饲料中VE的适宜含量为5-10mg/100g饲料。  相似文献   
80.
皱纹盘鲍人工诱导雌核发育精子遗传失活的初步研究   总被引:11,自引:0,他引:11  
张国范 《海洋科学》2001,25(10):37-39
用波长253.7nm,光照强度1.108mW/cm^2的不同剂量紫外线照射皱纹盘鲍(Haliotis discus hannai Ino)精子,然后与皱纹盘鲍的正常卵受精。在0-120s的照射范围内,受精作用都仍能正常发生,从早期胚胎存活率上可观察到“Hertwig”效应的存在,单倍体和非整倍体胚胎在孵化前死亡。在150000个精子/cm^2的条件下,精液厚度5mm左右,经70s以上紫外线照射后,精子染色体可完全失活。  相似文献   
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