基于CAN总线的多点温湿度检测系统

本文介绍了基于CAN总线的多点温湿度检测系统的整体设计,详细介绍了各部分的组成.经过现场应用表明,设计合理,可靠性高.     

钨钼活化烧结机理

主要介绍了添加少量Ｎｉ－Ｃｏ时钨，钼的低温烧结特性，对比了纯钨，Ｗ－Ｃｏ，Ｗ－Ｎｉ，Ｗ－Ｎｉ－Ｃｏ，纯钼，Ｍｏ－Ｃｏ，Ｍｏ－Ｎｉ，Ｍｏ－Ｎｉ－Ｃｏ烧结体系，测算了这些体系的烧结活化能，研究了其低温烧结机理，发现Ｎｉ－Ｃｏ对钨，钼的烧结具有最好的活化效果，说明镍与钴的共同加入对钨，钼的烧结具有协同活化作用。     

分流液压转向牵引计算的展开图及其应用

本文论及分流液压转向牵引计算的概念,方法及其展开图,并且提供了计算机绘制的展开图和应用实例。     

核医学成像技术中计算机的应用

由于计算机和核医学的结合,各种成像方法的计算机化医学图像层析技术正在迅速发展,并开始广泛应用。本文介绍各类成像技术中计算机的应用,特别评述其最近进展,并提出了今后的展望。     

推力矢量控制技术在导弹上的应用及发展

简要介绍了推力矢量控制技术的概念,分析了推力矢量控制的基本原理及特点.在简要分析其技术发展历程的基础上,给出了导弹推力矢量技术的现状和发展趋势.     

Fuzzy control of nitrogen removal in predenitrification process using ORP.

In order to meet increasingly stringent discharge standards, new applications and control strategies for the sustainable removal of nitrogen from wastewater have to be implemented. In the past years, numerous studies have been carried out dealing with the application of fuzzy logic to improve the control of the activated sludge process. In this paper, fuzzy control strategies of predenitrification systems are presented that could lead to better effluent quality and, in parallel, to a reduction of chemicals consumption. Extensive experimental investigations on lab scale plant studies have shown that there was excellent correlation between nitrate concentration and ORP value at the end of the anoxic zone. Results indicated that ORP could be used as an on-line fuzzy control parameter of nitrate recirculation and external carbon addition. The optimal value of ORP to control nitrate recirculation and external carbon addition was - 86 +/- 2 mV and - 90 +/- 2 mV, respectively. The results obtained with real wastewater also showed the good performance and stability of the fuzzy controllers independently from external disturbances. The integrated control structure of nitrate recirculation and external carbon addition in the predenitrification system is also presented.     

One‐step production of 2,3‐butanediol from starch by secretory over‐expression of amylase in Klebsiella pneumoniae

BACKGROUND: 2,3‐Butanediol (2,3‐BD) is a valuable chemical that can be biosynthesized from many kinds of substrates. For commercial biological production of 2,3‐BD, it is desirable to use cheap substrate without pretreatment, such as starch. However, there have been few reports on the production of 2,3‐BD directly from starch. RESULTS: In this work, gene malS coding for α‐amylase (EC 3.2.1.1) precursor was inserted into plasmid pUC18K, and secretory over‐expression of α‐amylase was achieved by engineered Klebsiella pneumoniae. The extracellular recombinant amylase accelerated the hydrolyzation of starch, and one‐step production of 2,3‐BD from starch was carried out by engineered K. pneumoniae. A 2,3‐BD concentration of 3.8 g L^?1 and yield of 0.19 g 2,3‐BD g^?1 starch were obtained after 24 h fermentation. CONCLUSION: The one‐step production of 2,3‐BD from starch was achieved by secretory over‐expression of amylase in K. pneumoniae. This would simplify the process and reduce the production cost considerably by enabling use of starch with minimal pretreatment. Copyright © 2008 Society of Chemical Industry