Effect of gums on viability and β‐galactosidase activity of Lactobacillus spp. in milk drink during refrigerated storage

The viability and β‐galactosidase activity of four Lactobacillus strains in milk drink containing gums during 28 days of refrigerated storage at 4 °C were assessed. The population of Lactobacillus rhamnosus GGB101 and Lactobacillus rhamnosus GGB103 were maintained, whereas the population of Lactobacillus reuteri DSM20016 and Lactobacillus reuteri SD2112 significantly decreased. The recommended level of 6 log CFU g^?1 was exceeded for all tested trains throughout storage. The highest viable number of Lactobacillus rhamnosus GGB103 (8.76 ± 0.03 log CFU mL^?1) was obtained in the product containing carrageenan–maltodextrin. The addition of guar–locust bean–carrageenan led to 20‐fold increase in the level of β‐galactosidase activity for L. rhamnosus GGB101 (1208 ± 2.12 Miller units mL^?1) compared to the control (61 ± 2.83 Miller units mL^?1). Our results suggested that gums could be added to milk to improve viability and enhance β‐galactosidase activity of Lactobacillus.     

安家岭露天矿过采空区危险源辨识及安全措施研究

危险源辨识对提高煤矿安全生产具有重要的现实意义。研究建立了基于层次分析法的安家岭露天矿危险源辨识模型,确定了危险源指标的权重。依据危险源辨识的权重研究了安家岭露天矿过采空区安全开采存在的主要危险源,并把采空区分为高温明火采空区、积水采空区、存在有毒气体的采空区、未冒实采空区,针对不同的类别的采空区提出了相应的安全开采措施。     

马钢张庄矿高压辊磨机装配工艺研究

针对马钢张庄矿高压辊磨机辊套疲劳断裂严重、对辊精度不能满足生产要求等问题，马钢重机公司根据张庄矿实际生产要求对对辊进行国产化，国产化内容包括辊轴、辊套等零部件的新制以及装配工艺攻关，通过技术研发同时结合实际生产经验，成功对高压辊磨机辊套与辊轴以及辊轴与轴承进行装配，完成了张庄矿高压辊磨机整对对辊的国产化，为该型设备后续生产及优化提供了理论和实践参考依据。     

CMP系统技术与市场

概述了CMP系统技术的发展历史、发展趋势以及在IC生产中的重要性,介绍了国外CMP设备主要制造厂家的设备型号和性能及CMP设备市场分布和需求,阐述了CMP系统技术的基础研究、关键技术和国内研究概况。     

A noncompetitive peptide inhibitor of the nicotinic acetylcholine receptor from Conus purpurascens venom

A paralytic peptide, psi-conotoxin Piiie has been purified and characterized from Conus purpurascens venom. Electrophysiological studies indicate that the peptide inhibits the nicotinic acetylcholine receptor (nAChR). However, the peptide does not block the binding of alpha-bungarotoxin, a competitive nAChR antagonist. Thus, psi-conotoxin Piiie appears to inhibit the receptor at a site other than the acetylcholine-binding site. As ascertained by sequence analysis, mass spectrometry, and chemical synthesis, the peptide has the following covalent structure: HOOCCLYGKCRRYOGCSSASCCQR* (O = 4-trans hydroxyproline; * indicates an amidated C-terminus). The disulfide connectivity of the toxin is unrelated to the alpha- or the alphaA-conotoxins, the Conus peptide families that are competitive inhibitors of the nAChR, but shows homology to the mu-conotoxins (which are Na+ channel blockers).     

A comparative analysis of fuzzy logic and PI speed control in high-performance AC drives using experimental approach

One of the frequently discussed applications of artificial intelligence in motion control is the replacement of a standard proportional plus integral (PI) speed controller with a fuzzy logic (FL) speed controller. Regardless of all the work, it appears that a thorough comparison of the drive behavior under PI and FL speed control is still missing. This paper attempts to fill in this gap, by providing an in-depth comparison of operation of a vector-controlled permanent-magnet synchronous motor, using at first an experimental rig. Speed responses, obtained under PI and FL speed control, are recorded and compared for a variety of operating conditions. The transients studied include response to a large step speed command from standstill with nominal inertia and an increased inertia, response to small step speed reference change, and response to step load torque application. The transient behavior is examined for various initial speed settings, so that a thorough comparison is enabled. Experimental results are further supplemented with a set of simulation results, obtained using a different permanent-magnet machine and a different FL controller. Better generalization of the results is enabled in this way. It is shown that superiority of the FL speed control is less pronounced than it is often portrayed in the literature on the basis of limited comparisons. Indeed, in a number of cases, PI speed control provides a superior speed response.     

Thermoelectric properties of BiSb alloys

Bismuth is a semimetal that has a relatively low lattice thermal conductivity. A positive energy gap can be created by alloying with antimony, leading to useful alloys for thermoelectric energy conversion. This paper gives an insight into the basic properties of BiSb alloys for thermoelectric applications.     

IPv6过渡机制讨论

本文在简要地介绍Ngtrans工作组提出的大多数过渡机制的基础上，尝试对它们进行区分、分类，并对每一种过渡机制的优缺点进行分析。另外．还对这些机制的布置以及一部分支持这些机制的产品平台进行讨论。