水泥搅拌桩在城陵矶新港区（松阳湖）软基处理中的应用

文章以岳阳城陵矶新港区(松阳湖)堆载软基处理工程为背景,简要阐述了水泥搅拌桩的加固原理与工作性能,并通过室内与现场试验研究,着重分析了影响搅拌桩成桩质量的因素,获得了适合工程实际情况的水泥搅拌桩设计参数与施工工艺参数,试验结果为新港区大面积施工提供了依据.可供环洞庭湖地区软基处理工程参考.     

Prediction of Mass Transfer Coefficients in a Packed Bed using Tamarind Nut Shell Activated Carbon to Remove Phenol

Phenol is a refractive pollutant that is generated from almost all the types of industries. Removal of phenol can be achieved economically by using a cost effective technique like adsorption on to activated carbon. The present paper reports on the preparation and characterization of activated carbon from tamarind nutshell, an agricultural waste byproduct, and its use in a packed bed for the removal of phenol. The breakthrough curves for column sorption of phenol from aqueous solutions to TNSAC have been measured at various flow rates and different particle sizes at 28 °C. The results obtained showed that the sorption of phenol is dependent on both the flow rate and the particle size of the adsorbent, and that the breakpoint time and phenol removal yield decrease with increasing flow rate and particle size. The overall mass transfer coefficient is calculated from the experimental data and compared with the values obtained from the correlation. Experimental values are in excellent agreement with the predicted values from the correlation.     

cDNA fingerprinting of osteoprogenitor cells to isolate differentiation stage-specific genes

A cDNA fingerprinting strategy was developed to identify genes based on their differential expression pattern during osteoblast development. Preliminary biological and molecular staging of cDNA pools prepared by global amplification PCR allowed discrim-inating choices to be made in selection of expressed sequence tags (ESTs) to be isolated. Sequencing of selected ESTs confirmed that both known and novel genes can be isolated from any developmental stage of interest, e.g. from primitive progenitors, intermediate precursors or mature osteoblasts. EST expression provides insight into possible interrelated physiological functions and putative interacting molecules during differentiation. This method offers a functional genomics approach to isolate differentiation stage-specific genes in samples as small as a single cell.     

嵌入式Linux在新型仪器交叉站中的应用

本文介绍了一种基于嵌入武Linux的交叉站设计方案,分别从交叉站的硬件平台、嵌入式Linux操作系统以及系统应用软件设计流程等方面进行阐述;并利用Intel XScale系列的IXP460微处理器实现了嵌入式Linux的交叉站设计.通过测试和实验,达到了预期的设计要求,显示了嵌入式系统具有针对性和实时性的设计,提高了资源利用率,成本低,性能高,并具备应用软件在系统可升级的功能.     

Continuum Bed Model for Estuarine Sediments Based on Nonlinear Consolidation Theory

The goal of this note is to examine a continuum theory that describes the evolution of sediment beds when subjected to time-dependent shearing forces resulting from surface water movement. The bed was conceptualized as a medium with continuously varying properties such as shear strength and void ratio. The nonlinear equation describing finite strain consolidation, and the complicated nature of the shearing forces acting on top of the bed, preclude the possibility of analytical solutions. Ramifications of linearizing the governing flow equations were explicitly evaluated for applications in bed modeling. Numerical solutions were obtained for the linear and nonlinear models under transient boundary conditions. Model results indicated that the linear model typically predicts lower void ratios, and consequently underestimates the amounts of sediment eroded from the bed as compared to the nonlinear model.     

Progressive bounds on merit factor

Two usual criteria of goodness of pulse compression sequences are the discrimination and the merit factor. Using the notion of equivalence of l/sub p/ norms, they are related by an inequality. Using bounds on the aperiodic autocorrelation, the inequality is strengthened further to obtain a bound on the merit factor in terms of the length of the sequence and the Barker progression number.<>     

An improved iterative finite element solution for pin joints

Accurate, reliable and economical methods of determining stress distributions are important for fastener joints. In the past the contact stress problems in these mechanically fastened joints using interference or push or clearance fit pins were solved using both inverse and iterative techniques. Inverse techniques were found to be most efficient, but at times inadequate in the presence of asymmetries. Iterative techniques based on the finite element method of analysis have wider applications, but they have the major drawbacks of being expensive and time-consuming. In this paper an improved finite element technique for iteration is presented to overcome these drawbacks. The improved iterative technique employs a frontal solver for elimination of variables not requiring iteration, by creation of a dummy element. This automatically results in a large reduction in computer time and in the size of the problem to be handled during iteration. Numerical results are compared with those available in the literature. The method is used to study an eccentrically located pin in a quasi-isotropic laminated plate under uniform tension.     

Effect of texture and grain size on the mechanical properties of warm-worked cadmium,zinc and zinc-0·35% aluminium alloy

Changes in the grain size and crystallographic texture during warm working and their influence on the room temperature mechanical properties are investigated on Cd, Zn and a Zn-Al alloy. The yield strength increase in the early stages of working in extruded cadmium is accounted for based on the development of a basal texture while in rolled zinc and zinc alloy, the properties are affected more by the grain size. Cadmium exhibits ductile fracture at all extrusion ratios whereas the fracture mode in zinc and the alloy changes from cleavage at small rolling strains to ductile at higher deformation strains.     

Solar cookers—part-II—cooking vessel with central annular cavity

Cooking vessels used in a solar cooker must be able to transfer the heat trapped in the cooker effectively to the food material. In the preceding paper (Part-I) the advantage of keeping the vessel on lugs was discussed. In the current paper the performance of a cooking vessel with a central annular cavity kept on lugs is discussed. The experiments were conducted for several days using water and thermic fluid as working medium. The studies indicated that the cooking vessel with central annular cavity on lugs performs much better than the conventional vessel kept on the floor of the cooker. The conventional vessel is considered to be the benchmark for the purposes of comparison.