The prediction of the hydrodynamic performance of marine current turbines

The development of a blade element momentum (BEM) model for the hydrodynamic design of marine current turbines is presented. The model includes routines for interpolation of 2D section data and extrapolation for stall delay. The numerical model is compared with experimental data obtained from tests of an 800 mm diameter model rotor carried out in a cavitation tunnel. The theoretical predictions are in good agreement with the experiments. Using this validated model, a typical 3D rotor is used to demonstrate parametric variations of the design parameters. The effect of tip immersion on possible cavitation is assessed for this rotor. The model is then used to solve the dynamic effects of a tidal profile. The effect of an increase in blade roughness is presented, indicating a relatively small reduction in power. This work demonstrates that the numerical model developed can provide a useful tool for the investigation of the hydrodynamic design and operation of marine current turbines.     

Euryhaline Hydrogel with Constant Swelling and Salinity-Enhanced Mechanical Strength in a Wide Salinity Range

In nature, many biological organisms possess a unique osmoregulation feature that enables them to survive in environments of different salinity, which is called euryhaline characteristics (e.g., salmon that can survive in freshwater and seawater). Drawing inspiration from these salinity-tolerant organisms, here a strategy that integrates two polymer chain segments with different salinity tolerances is reported to produce a euryhaline hydrogel with stable water retention, constant swelling properties, superoleophobicity, and low-adhesion to oil in aqueous environments over a wide range of salinity. The formation of internal dynamic complementary crosslinks is a key structural factor of the euryhaline attributes. The euryhaline hydrogel-coated meshes can be successfully utilized in various oil/aqueous phase separation in a wide range of salinity. Furthermore, by creating a double network with dynamic bonds, superior euryhaline hydrogel with unique salinity-enhanced mechanical strength can be obtained. It is anticipated that the euryhaline hydrogel will have broad application prospects in complex and variable ionic environments.     

Chitosan and marine phospholipids reduce matrix metalloproteinase activity in myeloma SP2 tumor‐bearing mice

An animal experiment was conducted to assess the antitumor effects of chitosan‐coated liposomes on myeloma SP2. The animal experimental groups designed for myeloma SP2 tumor‐bearing BALB/c mice were provided with five different drinks: (I) control (double‐distilled water); (II) squid phospholipid liposomes alone 1.0 mg/mL; (III) chitosan alone 5.0 mg/mL; (IV) squid phospholipid liposomes 1.0 mg/mL with chitosan 5.0 mg/mL in the form of a simple mixture; and (V) squid phospholipid liposomes 1.0 mg/mL coated with chitosan 5.0 mg/mL. At 20 days after implantation of the myeloma SP2 cells into mice, oral administration of the experimental drinks was provided for 35 days. There was significant suppression of tumor growth when chitosan and squid phospholipids were administered simultaneously in a simple mixture or as chitosan‐coated liposomes. Matrix metalloproteinase (MMP)‐2 and MMP‐9 activity was significantly less in the serum of mice that consumed chitosan‐coated liposomes than in control mice. We found that decreased tumor burden was related to MMP secretion. Therefore, chitosan‐coated marine phospholipid liposomes might be useful as potential agents for the treatment of myeloma SP2.     

Electrochemical behavior of microbiologically influenced corrosion on Fe3A1 in marine environment

the passivating film of the inner layer was absolutely destroyed by microbial metabolic products.     

Geographic information system applied to measuring benthic environmental impact with chemical measures on mariculture at Penghu Islet in Taiwan

Cobia, Rachycentron canadum, is currently grown by marine aquaculture in Taiwan, particularly on Penghu Islet. Although the effect of marine aquaculture on the environment has been the subject of many studies, an understanding of its environmental impact has yet to be attained, and the continuing expansion of cage farming has caused noticeable ecological declines. Nevertheless, useful tools to measure this environmental degradation are scant. The results of this study suggest that the combination of a geographic information system (GIS) with redox potential and sulfide measurements can be used to definitively assess the condition of the benthic environment near cobia aquaculture sites and to help develop environmental monitoring programs. These applications could easily be adopted to assess multiple marine environmental conditions.     

Call For Paper The 9th International Workshop on Ship and Marine Hydrodynamics（IWSH＇2015, 26- 28 August 2015, Glasgow,UK）

<正>In 1999,the first International Workshop on Ship Hydrodynamics was successfully held in Wuhan,China.Then it was held in Wuhan,Shanghai,Zhenjiang,Harbin,Seoul in subsequent every two years.These Conferences had drawn a variety of international delegates including scientists,engineers and researchers with a common interest in ship hydrodynamics.They provided a forum to promote scientific advancement,technological progress,information exchange,and cooperation among engineers and researchers in ship and ocean engineering and other related fields.The coming IWSH’2015 conference will change its full name to International Workshop on Ship and Marine Hydrodynamics.It will be hosted and organized by University of Strathclyde,UK and sponsored by Lloyd’s Register,UK.The IWSH’2015 will be a platform for engineers and researchers to keep abreast     

舟山市海产贝类和食源性腹泻病例中肠道腹泻病毒监测

目的了解肠道腹泻病毒在舟山市海产贝类的分布和食源性腹泻病例中的感染特征以及两者相关联系,为预防和控制食源性疾病提供有效的对策和措施。方法采用荧光定量聚合酶链式反应(PCR)方法对466份舟山市海产贝类和422份食源性腹泻标本中诺如病毒(NoV)GⅠ型/GⅡ型、轮状病毒(RV)、札如病毒(SPV)、星状病毒(AsV)和肠道腺病毒(AdV)5种主要肠道腹泻病毒核酸进行检测。结果 466份海产贝类样品病毒总阳性率为18.03%(84/466),其中NoV GⅡ型为4.08%(19/466),SPV为9.67%(45/466),AsV为2.79%(13/466),AdV为1.50%(7/466);春季和冬季病毒阳性率较高,农贸市场的牡蛎病毒阳性率最高(24.75%,25/101),养殖毛蚶病毒阳性率最低(10.12%,17/168),不同的病毒阳性率以及不同来源和不同季节贝类的病毒阳性率差异均有统计学意义(P0.05)。422例腹泻患者粪便标本总阳性率为15.64%(66/422),NoV为4.74%(20/422,以GⅡ为主),RV为4.74%(20/422),SPV为3.55%(15/422),NoV GⅡ型、RV和SPV的阳性率相对较高,春季和冬季病毒阳性率较高,不同病毒阳性率和不同季节病毒阳性率差异有统计学意义(P0.05)。结论舟山市海产贝类中肠道腹泻病毒的污染状况较为严重,与食源性腹泻病例中的病毒感染特征存在相关联系,其流行季节和优势病毒类型相同。     

上海奉贤区海湾海洋细菌的鉴定与分离

本文对上海奉贤区海湾的海洋细菌进行分离、鉴定研究.研究表明以人工海水配制的培养基分离效果较好,筛选出对海水与海泥中细菌的分离效果较好的培养基,本研究共分离到了206株海洋细菌,经细菌学的鉴定,它们是分属6个不同的海洋细菌属.     

Modeling impact of culture facilities on hydrodynamics and solute transport in marine aquaculture waters of North Yellow Sea

An increasing number of marine aquaculture facilities have been placed in shallow bays and open sea, which might significantly affect hydrodynamic and solute transport processes in marine aquaculture waters. In this study, a coupled hydrodynamic and solute transport model was developed with high-resolution schemes in marine aquaculture waters based on depth-averaged shallow water equations. A new expression of drag force was incorporated into the momentum equations to express the resistance of suspended culture cages. The coupled model was used to simulate the effect of suspended structures on tidal currents and the movement of a contaminant cloud in the marine aquaculture of the North Yellow Sea, China. The simulation results showed a low-velocity area appearing inside the aquaculture cage area, with a maximum reduction rate of velocity close to 45% under high-density culture. The results also showed that tidal currents were sensitive to the density of suspended cages, the length of cages, and the drag coefficients of cages. The transport processes of pollutants inside aquaculture facilities were inhibited away from the vicinity of the culture cage area because of the diminished tidal currents. Therefore, the suspended cages significantly affected the transport processes of pollutants in the coastal aquaculture waters. Furthermore, the reduced horizontal velocity significantly decreased the food supply for the aquaculture areas from the surrounding sea.     

DESORPTION ISOTHERMS AND DRYING CHARACTERISTICS OF SHRIMP IN SUPERHEATED STEAM AND HOT AIR

Desorption isotherms for shrimp were determined at the temperatures of 50, 60, 70 and 80°C. Amongst the moisture equilibrium predictions between the BET and GAB models, the latter has a better predictable capability. The GAB parameters are correlated with the temperatures by the Arrhenius expression. Drying characteristics of shrimp in drying media at the temperature range of 120-180°C for superheated steam and of 70-140°C for hot air have been examined. Drying rate and effective diffusion coefficient are used to quantify quantitatively the difference between the superheated steam and the hot air dryings. The temperature is more important effect on drying rate and effective diffusion coefficient in the superheated steam than in the hot air. Inversion temperature exists between 140 and 150°C. Comparing to the hot air, the shrimp dried by the superheated steam shows a lower degree of shrimp shrinkage. In addition, product colours are slightly different to those from the commercial sources.