A REVIEW OF TEXTURAL DEFECTS IN COOKED RECONSTITUTED LEGUMES —THE INFLUENCE OF STRUCTURE AND COMPOSITION

Legumes provide an important part of the world's protein requirements, as well as other nutrients, but they are underutilized as food. A major factor limiting expanded consumption is storage induced textural defects that prolong cooking time and demand correspondingly higher energy requirements for preparation. These defects, including the hard-to-cook phenomenon and hardshell, are initiated by structural and compositional factors but can be at least partially controlled by storage and processing conditions. Structural components implicated include seed coat, cell walls, middle lamella, starch granules and membranes while, compositionally, proteins, carbohydrates, phytate, polyphenols and lignin may also be important. Methods of texture measurement of legumes, including mechanical, physical and sensory properties are reviewed. The most commonly held hypothesis for the mechanism of the hard-to-cook defect states that beans fail to soften after exposure to high temperature and humidity storage because the increased water activity potentiates phytase which hydrolyzes phytate, rendering it no longer capable of chelating the Ca⁺⁺ and Mg⁺⁺ ions of the middle lamella and, hence, undissoluble. More recent evidence, however, provides potential roles for lignification, starch gelatinization and perhaps other mechanisms depending upon conditions. The possibility of a nonenzymatic as well as an enzymatic route is raised and thoughts presented on a course of action for future research.     

Deformation Behavior of Polycrystalline Aluminum Oxide

The steady-state creep behavior of polycrystalline aluminum oxide from 97 to 100% dense has been examined at temperatures from 1600° to 1800°C over a range of stresses from 100 to 2000 psi under four-point transverse bending. Grain size is shown to have an important effect on the deformation behavior. Stress-strain rate dependence for the fine-grained aluminum oxide (3 to 13μ) is of viscous behavior (°_ε∼σ). The strain rate is also inversely proportional to the square of the grain size (°_ε∼ 1/(GS)²). The creep behavior can be described by the Nabarro-Herring diffusional flow model although the diffusion coefficient does not agree with that for oxygen diffusion in sapphire. When the grain size becomes coarse, the Nabarro-Herring model no longer applies. Coarse-grained aluminum oxide (50 to 100μl) behaves plastically when deformed (°_ε∼σ). The strain rates observed on coarsegrained aluminum oxide are higher than one would predict from the deformation behavior of fine-grained aluminum oxide. This plastic flow probably occurs through some dislocation movement or glide mechanism.     

平台式FPGA中可重构存储器模块的设计

可重构静态存储器(SRAM)模块是场可编程门阵列(FPGA)的重要组成部分,它必须尽量满足用户不同的需要,所以要有良好的可重构性能.本文设计了一款深亚微米工艺下的16-kb的高速,低功耗双端口可重构SRAM.它可以重构成16Kx1,8Kx2,4Kx4,2Kx8,1Kx16和512x32六种不同的工作模式.基于不同的配置选择,此SRAM可以配置为双端口SRAM,单端口SRAM,ROM,FIFO,大的查找表或移位寄存器,本文完整介绍了该SRAM的设计方法,重点介绍了一种新颖的存储单元电路结构:三端口存储单元,以及用于实现可重构功能的电路的设计方法.     

Commercialization of remote-sensing technology

The Technology Application Center (TAC) has 10 years of experience transferring applied remote-sensing technology and has assisted numerous organizations in their commercialization efforts. Management and cost data for 48 completed projects are presented that shed light on small business expectations regarding frequency and duration of projects, levels of effort required to complete projects and before-profit revenues. TAC's projects have averaged almost 10 months in length with a 4 month interval between contracts at an average contract amount of about $ 27000. The gross average salary per full time equivalent ( FTE) has averaged only $ 10 500 since 1975 suggesting that the market-place has still not developed sufficiently to support the skills required by the technology.     

Accounting for prior practice in skill acquisition studies

The application of a previously developed method for fitting skill acquisition data with hyperbolic functions is shown by means of ft model and actual data. The hyperbolic function yields explicit information on prior practice. The ability to account for prior practice makes it possible to analyse experimental methodology in a more rigorous manner than previously possible. The error that may be inherent in typical procedures can be quantified. The errors are greatest at early stages of learning, smallest when learning is far advanced. From the equations, one can calculate the number of trials required before the error term is below a. specified value.     

Probability density fittings of corrosion test-data: Implications on C6H15NO3 effectiveness on concrete steel-rebar corrosion

In this study, corrosion test-data of steel-rebar in concrete were subjected to the fittings of the Normal, Gumbel and the Weibull probability distribution functions. This was done to investigate the suitability of the results of the fitted test-data, by these distributions, for modelling the effectiveness of C₆H₁₅NO₃, triethanolamine (TEA), admixtures on the corrosion of steel-rebar in concrete in NaCl and in H₂SO₄ test-media. For this, six different concentrations of TEA were admixed in replicates of steel-reinforced concrete samples which were immersed in the saline/marine and the microbial/industrial simulating test-environments for seventy-five days. From these, distribution fittings of the non-destructive electrochemical measurements were subjected to the Kolmogorov–Smirnov goodness-of-fit statistics and to the analyses of variance modelling for studying test-data compatibility to the fittings and testing significance. Although all fittings of test-data followed similar trends of significant testing, the fittings of the corrosion rate test data followed the Weibull more than the Normal and the Gumbel distribution fittings, thus supporting use of the Weibull fittings for modelling effectiveness. The effectiveness models on rebar corrosion, based on these, identified 0.083% TEA with optimal inhibition efficiency, η = 72.17± 10.68%, in NaCl medium while 0.667% TEA was the only admixture with positive effectiveness, η = 56.45±15.85%, in H₂SO₄ medium. These results bear implications on the concentrations of TEA for effective corrosion protection of concrete steel-rebar in saline/marine and in industrial/microbial environments.     

Distortion cancellation in an unbalanced differential amplifier

In a differential amplifier in which the two transistors arc matched and carry the same quiescent current the second harmonic distortion generated by the emitter-base diode is exactly cancelled. When unequal currents are taken by the two transistors the cancellation is much reduced. It is shown here that the choice of a suitable current source resistance allows the cancellation condition to be restored in the unbalanced case.