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21.
This paper rises the question, if it will ever be possible to put an artificial human into practice. Also it inquires, how far microelectronic technologies in medicine have approached in the year 2001.  相似文献   
22.
β-(1·3)(1·4)-Glucans are the major components of isolated endosperm cell walls of both sorghum and barley grains and the concentration declines from 75% in unmalted barley walls to 32% in those of the 6-day malts. In sorghums over the same period, the reduction was from 72 and 68% to 54 and 62% in varieties L187 and SK5912, respectively. Following germination wall pentosans, while enhanced in barley, decreased in sorghum. The enzymes which were unable to hydrolyse the walls of sorghum to release sugars (unlike those of barley) did so after the walls had been solubilised in alkali. Cellobiose accounted for 43% of the hydrolysates of the alkali-solubilised walls when incubated with sorghum malt enzymes and 79% when barley enzymes were used. Laminaribiose was not detected in either case which indicates that the polysaccharide of the sorghum walls is largely of a ‘cellulosic’ nature. Preliminary evidence suggests that fuco-xyloglucan may contribute to the resistance of the sorghum endosperm cell walls to enzymic attack during germination.  相似文献   
23.
A fault-tolerant high-performance SElf-Routing 2 × 2 Optical ATM Switch (SEROS) is proposed. The switch is designed using all-optical components which allows the exploitation of spatial parallelism. SEROS can be used with any multistage interconnection network such as Omega, Banyan, Shuffle or Benes. For the purpose of this study, SEROS has been incorporated into a generic self-routing multistage interconnection network that uses 2 × 2 switches and is not fault tolerant. Reliability analysis is carried out and the results are compared with two major fault-tolerant networks. They show that without redundant switches, better network survivability is achieved. All the switches in the network are 2 × 2, making it easier to mass produce.  相似文献   
24.
The sex pheromone of aPlanotortrix excessana sibling species was investigated. Females were found to produce eight potential pheromone components: dodecyl acetate, tetradecyl acetate (14OAc). (Z)-5-tetradecenyl acetate (Z5-14OAc), (Z)-7-tetradecenyl acetate (Z7-14OAc), (Z)-9-tetradecenyl acetate, hexadecyl acetate, (Z)-7-hexadecenyl acetate, and (Z)-9-hexadecenyl acetate. When these compounds were bioassayed using field-trapping and wind-tunnel techniques, only 14OAc,Z5-14OAc, andZ7-14OAc were found to be behaviorally active. The sex pheromone glands of females of other species including,Planotortrix MBS,Planotortrix M,P. notophaea, Ctenopseustis servana, and aC. obliquana sibling species, were also found to containZ5-14OAc orZ7-14OAc, singly or in combination. In the case ofPlanotortrix M, the addition ofZ7-14OAc to the previously identified sex pheromone blend ofZ5-14OAc and 14OAc was found to increase trap captures of male moths of this species. Thus in these New Zealand species (and in some Australian species),Z5-14OAc andZ7-14OAc appear to be utilized in combination in pheromonal communication just as (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate are used by many species of Holarctic Tortricidae in the tribe Archipini.Lepidoptera: Tortricidae: Tortricinae.  相似文献   
25.
Solubility, emulsion stability and gelation of isolated soy proteins and their 7S and 11S fractions from three stages of seed maturity were studied. The pH-solubility profile was similar irrespective of maturation and six-month storage. The 11S protein was more soluble in the acidic pH range than the 7S protein. Oil-in-water emulsion stability of isolated soy protein from mature soybeans was higher than that from the immature ones. This is due to the fact that there was more 7S fraction in the mature soybeans, and 7S protein was found to form a more stable emulsion than that formed from 11S protein. The result suggests that isolated soy protein from mature soybeans would serve as a better emulsifying agent. Heat-induced soy protein gels became weaker as the soybeans became more mature. This can be attributed to the higher content in the immature soybeans of 11S fraction which gives a stronger gel than 7S fraction in the protein from immature soybeans.  相似文献   
26.
针对西门子S7-300可编程控制器的脉冲输出功能,将25个半音阶音符的周期及对应的脉冲数存放S7-300相应的内存单元中,通过合理分配S7-300的I/O端口,设计了一种音乐演奏控制系统.在硬件电路和软件编程的基础上,结合Wincc flexible仿真软件进行仿真与调试,实现了音乐演奏系统的功能需求.实践表明,该设计具有功能强、运用灵活、可靠性高、稳定性好、编程简单、使用方便以及体积小、功耗低等特点.  相似文献   
27.
Among the new materials currently employed as electron donor element in active layers of organic solar cells (OSCs), PTB7 holds the best results. It has been extensively studied and now there is a search for new derivatives to improve its properties. In this work, a set of 24 polymers derived from polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) was studied theoretically, using chemical modifications in the benzodithiophene (BDT) moiety of the PTB7 monomeric units. After evaluations of the electronic and optical properties, including the open circuit voltage and exciton dissociation and recombination conditions, the results indicate that employing chlorine as substituent yields the most promising material for application in active layers together with Phenyl-C61-Butyric-Acid-Methyl-Ester (PCBM) as electron acceptor material.  相似文献   
28.
A high quality electric power supply needs adequate power quality and reliability. Voltage dips lead to a strong decrease of power quality. With the network data and the fault and disturbance statistics of the network, the expected number of voltage dips per year and the distribution of their amplitudes and durations can be calculated. This paper presents two calculation methods which are compared to measurement results. With these numbers, an estimation of the failure costs for customers is possible. Furthermore the influence of different network improvements on social economic costs is shown with a simple example network.  相似文献   
29.
由于现有桩基施工现场各种因素干扰,环境较差,容易对实验数据的传输造成困难,在这种情况下,设计出一种基于USB接口的数据传输测控系统。对系统结构做整体介绍,并且对USB硬软件设计进行了阐述。实验结果表明,该设计增强了系统的抗干扰能力,提高了数据传输速率,系统稳定可靠。  相似文献   
30.
介绍了在C&CSMNO.7信令集中监测系统节点机部分实时处理程序中使用VisualC++的多媒体定时器实现对LSSU消息的实时处理,提高了系统的处理精度。  相似文献   
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