SOME BARLEY GRAIN AND GREEN MALT PROPERTIES AND THEIR INFLUENCE ON MALT HOT-WATER EXTRACT: II. PROTEIN,PROTEINASE AND MOISTURE

This paper continues the study of variation between varieties in some properties of barley and malt and examines protein-related characters and moisture uptake. Initial rate of moisture uptake was more closely related to enzyme activities than maximum moisture content. Significant varietal variation was found in all characters and this variation was greater than environmental variation with the exception of grain nitrogen concentration. In the endosperm endopeptidase activity was the character most highly correlated with malt hot water extract (HWE). The combined influence of protein- and β-glucan-related characters was investigated and the relative influence of each group of characters on HWE varied in different sections of the grain. In the endosperm the protein- and β-glucan-related characters accounted for 30% and 60% of the variation in HWE respectively.     

DETERMINATION OF CADMIUM,COBALT, COPPER,LEAD AND ZINC IN BEER BY FLAME ATOMIC ABSORPTION SPECTROSCOPY

A method has been developed for the simultaneous determination of Cd, Co, Cu, Pb and Zn in beer at the levels found in this beverage. A previous ashing of organic matter and a subsequent liquid-liquid extraction with ammonium pyrrolidine dithiocarbamate/4 methyl-2-pentanone were carried out. The final determination was performed using flame atomic absorption spectroscopy The sensitivity [units of absorbance × (ng./g.)^?1], detection limit (ng./g.), precision (coefficient of variation) and recovery percentage were: Cd (133 × 10^?3, 0.005, 14%, 98±15), Co (127 × 10^?3, 0.02, 4%, 90±7), Cu (5.63 × 10^?3, 0.2, 11%, 103±6), Pb (15.8 × 10^?3, 0.1, 12%. 88±11), Zn (21.6 × 10^?3, 2, 6% 115±7). Different brands of beer from Spain and other European countries were analysed by this method. Metal contents of Spanish beers do not differ significantly from those found in foreign beers and all are well below the maximum levels permitted in international legislation. No differences were found between bottled and canned beers and no correlation exists between metal contents and original gravity of the beers. The method proposed is also applicable to the determination of all the elements mentioned above in lemonade and for Co, Cu and Pb in Spanish sparkling white wine (“cava”).     

图像多样性重排序技术综述

近年来互联网呈现出了爆炸式的增长,而与日常生活息息相关的图像资源变得更加重要,如何能够准确地获取所需的图像资源是当前多媒体搜索领域需要重点解决的问题。目前的大多工作围绕图像的相关性搜索重排序展开,对多样性搜索重排序的研究较少。相关性重排序是指对于返回结果来说,都是将相关的样本排在结果集的前列,但是很少考虑样本相互之间的联系,而多样性重排序是为了提高返回结果的多样性,也就是覆盖主题的多样性,以降低相关重排序中带来的信息冗余问题。文中对当前常见的几种算法评价并进行比较,并通过不同于文本重排的评价准则对性能进行评价。     

陶瓷封装电路内部水汽的稳定性控制

简述了集成电路陶瓷封装内部水汽含量的不稳定性,主要是由粘接材料导电胶在高温下分解释放出的水汽所造成的.不同的封装温度内部水汽含量不一样.说明导电胶应充分固化,尽可能在较低的温度下进行封盖.     

Redundancy Removal during High-Level Synthesis Using Scheduling Don‘t-Cares

Previous work in automata theory has shown how to eliminate sequential redundancy from networks of FSMs by finding sequences of inputs and outputs which are never communicated between components of the network. This paper shows that behavior automata—finite-state machines whose inputs and outputs are incompletely scheduled—exhibit similar properties. Using the behavior FSM (BFSM) as a model for scheduling, we show how to identify and eliminate both input and output scheduling dont-cares. When a scheduling dont-care is eliminated from a network of BFSMs, the register-transfer implementation is guaranteed not to suffer from the corresponding dont-care sequence. A definition of scheduling dont-cares improves our understanding of the foundations of high-level synthesis and the relationship between high-level and sequential optimization. In practice, scheduling dont-care elimination is a powerful tool for eliminating redundancy early in the design process.     

Effect of silver content on thermal fatigue life of Sn-xAg-0.5Cu flip-chip interconnects

The thermal fatigue properties of Sn-xAg-0.5Cu (x=1, 2, 3, and 4 in mass%) flip-chip interconnects were investigated to study the effect of silver content on thermal fatigue endurance. The solder joints with lower silver context (x=1 and 2) had a greater failure rate compared to those with higher silver content (x=3 and 4) in thermal fatigue testing. Cracks developed in the solders near the solder/chip interface for all joints tested. This crack propagation may be mainly governed by the nature of the solders themselves because the strain-concentrated area was similar for tested alloys independent of the silver content. From the microstructural observation, the fracture was a mixed mode, transgranular and intergranular, independent of the silver content. Higher silver content alloys (x=3 and 4) had finer Sn grains before thermal cycling according to the dispersion of the Ag₃Sn intermetallic compound, and even after the cycling, they suppressed microstructural coarsening, which degrades the fatigue resistance. The fatigue endurance of the solder joints was strongly correlated to the silver content, and solder joints with higher silver content had better fatigue resistance.     

水在渠道防渗工程冻害中的作用及防治冻害对策

我国东北、华北、西北等寒冷地区的渠道防渗工程，因多为薄板式结构，裸露面很大，同时经常与水接触，甚至在冬季负温下仍要输水运用，故其冻胀破坏更为严重，影响了工程效益的充分发挥。本文在简述水在渠道防渗工程冻害中的作用后，从渠道防渗工程的设计、施工和管理运用方面，提出了保证防渗层工程质量、降低基上水分、防止外水渗（流）入渠基、降低地下水位和管理运用等防治冻害较为具体的对策。     

P2P文件共享系统防止重复下载的方法研究

在P2P文件共享系统中,文件名的差异经常会导致文件被同一节点重复下载,为了降低P2P文件共享系统中摘要算法对文件进行整体和分块处理,下载前先比较文件MD5散列值的方资源重复下载率高的问题,文章提出采用MD5报文法来确定是否需要下载文件,从而有效地防止共享文件被同一节点重复下载.通过分析和利用MATLAB软件进行模拟试验,证明该方法能提高文件的下载效率.     

8031单片机在绝缘材料真空干燥中的应用

准确测定电工绝缘材料真空干燥过程中的含水量,并实现实时在线控制,在绝缘材料真空干燥工艺中具有重要的实践意义,本文论述以8031单片机为核心的微机系统对电工绝缘材料真空干燥过程中水分含量进行了实时在线监测的方法,并给出了硬件结构框图及软件流程图。