SCSI产品的未来?

通过在广泛普及的IP网络上传送SCSI命令,iSCSI市场终于准备好起步了。iSCSI承诺更为方便的企业内部互联网上的数据传输,以及简化长距离范围内的存储管理。在广泛的应用中,包括远程备份,远程镜像,SAN桥接和低成本的存储区域网,该技术预计可以为这些应用带来令人感到兴奋的新功能。新协议最终允许通过为光纤信道存储区域网提供一种新的低成本可选方案,以及比直连存储(DAS)更灵活的来实现快速的SAN部署。     

Estimation of metal temperature variations for scarred boiler tubes

Boiler tubes in a fossil-fuelled power station are subjected to erosion and corrosion that caused the tubes to become locally thinned or scarred. To avoid unscheduled tube failures and hence prevent large financial loss due to boiler shut-down and tube repairs, it is important to estimate boiler tube lives. Boiler tube lives are very sensitive to tube temperature. This paper describes the development of a non-dimensional parameter termed T^*. It is shown that T^* can be used to estimate the tube temperature variation in the scarred tube section. Also a method has been described for volume estimation and characterisation of a tube scar. This is important for more accurate tube life assessments.     

Lower bound to limit pressure for cylindrical shell with part-through slot

A lower bound to the limit pressure of a cylindrical shell with a rectangular slot part through the thickness at mid-length is computed using a linear optimization technique. The sides of the slot are axial and circumferential.The analysis has been carried out for internal pressure applied to the cylinder such that the longitudinal pressure end force is (a) not taken by the cylindrical shell, (b) wholly taken by the cylindrical shell.Different proportions of rectangular slot and different radius to thickness ratios of the cylinder have been considered. Results are presented for a range of parameters.     

Mechanical and thermo‐physical properties of high‐density polyethylene modified with talc

The aim of this study was to examine the physical, mechanical, and thermo‐physical properties of high‐density polyethylene (HDPE) modified with talc. Different weight fractions of talc (up to 35 wt %) were compounded with an HDPE matrix containing 2.5 wt % of carbon black (CB) in a twin‐screw compounder. The composites were then processed by injection moulding to obtain specimens for testing. The results indicate that CB causes a significant decrease in the toughness, while talc not only enhances the thermal conductivity and thermo‐physical properties of the composites but can also play a role in compensating for the negative effects of CB on impact resistance. The experimental data show that the presence of CB reduces the impact resistance of HDPE by up to 34%, while addition of up to 8 wt % talc can return this value to close to that of pure HDPE. No significant effect on the composite tensile yield and fracture strength was observed for either component at all concentrations. The thermal conductivity, thermal diffusivity, and specific density values of the composites increased almost linearly, but the increase in moisture absorption in the long term showed nonlinear behavior in the concentration range of the experiment. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

DETERMINATION OF PARAMETERS AND PRETREATMENT SOLUTION FOR GRAPE DRYING

The drying of Iranian seedless white grapes (sultana) was investigated in a batch operation in a laboratory dryer. The effect of pretreatment and temperature on the drying rate of grapes at constant air velocity were studied. Pretreatment solutions contained different alkaline materials in different concentrations and temperatures. Dipping grapes in an alkaline solution increased the drying rate substantially. Increasing the air temperature in the dryer from 60 to 70°C accelerated the drying rate (for a decrease in drying time) of the pretreated grape. Grapes dried in 450-900 min depending on pretreatment and air temperature. The shorter drying time and best quality dried product were obtained with grapes dipped in a solution of potassium carbonate of 5% at 42°C. The mean apparent diffusivity of moisture for K₂CO₃ pretreatment was calculated at 50, 60, and 70°C, and the values were fitted to an Arrhenius type model. Moisture sorption isotherms of currants were determined at 20, 30, and 40°C using static gravimetric methods. A modified Halsay equation was used to predict experimental data for water activity in a range of 0.1-0.85.     

Studying the corrosion protection properties of an epoxy coating containing different mixtures of strontium aluminum polyphosphate (SAPP) and zinc aluminum phosphate (ZPA) pigments

Epoxy/polyamide coatings were loaded with different mixtures of strontium aluminum polyphosphate (SAPP) and zinc aluminum phosphate (ZPA) pigments. Moreover, a coating containing zinc phosphate (ZP) was prepared as a reference sample. The coatings were applied on St-37 steel substrates and then were exposed to 3.5 wt% NaCl solution up to 35 days. The corrosion inhibition properties of the pigments extracts were studied on bare steel samples by a potentiodynamic polarization technique after 24 h immersion. The morphological properties and corrosion resistance of the coatings were investigated by scanning electron microscope (SEM), optical microscope, electrochemical impedance spectroscopy (EIS) and salt spray tests.     

Usage of lifestyle in housing studies: a systematic review paper

Journal of Housing and the Built Environment - A large body of studies was conducted on lifestyle in housing, but no comprehensive model has been designed and presented to address all components of...     

Overlap concentration of an aqueous poly(N-vinylcaprolactam) solution in the dynamic and static states

The overlap concentration of poly(N-vinylcaprolactam)s (PVCLs) of low molecular weights was studied with dynamic and static methods (with viscosity and refractive-index measurements) at three temperatures (25, 30, and 35°C). This concentration, determined by viscometry, was lower than the overlap concentration determined by refractometry. Also, the influence of the temperature and molecular weight on the viscosity and refractive index was investigated, and the opposite effect of the temperature on the viscosity and refractive index of PVCL solutions was observed. The experimental overlap concentration values were compared with those calculated with the Rao, Huggins, and Fuoss equations. The results showed that the Huggins equation is the best equation to describe the dilute solution properties of this polymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Utilization of RBF-ANN as a novel approach for estimation of asphaltene inhibition efficiency

One of the problematic concerns in petroleum industries is the deposition of heavy fractions of crude oil such as asphaltene fraction during production and transportation. The utilization of inhibitors is known as a relative low cost and effective method for asphaltene inhibition. In this study, Radial basis function artificial neural network (RBF-ANN) was applied to predict asphaltene precipitation reduction in terms of structure and concentration of inhibitor and oil properties. In order to training and testing of RBF-ANN the required data are extracted from reliable sources. The predicted asphaltene precipitation reduction values were compared with the actual data statistically and graphically. The coefficients of determination for training and testing phases of RBF-ANN were determined as 0.995906 and 0.994853 respectively. These evaluations showed that the RBF-ANN as a predictive tool has great capacity to estimate effect of asphaltene inhibitors on reduction of asphaltene precipitation.