基于USB总线的巡检仪通信接口设计

根据便携式巡检仪的总体设计要求,介绍了通用串行总线(USB2.0)与巡检仪单片机C8051F340的硬件连接。重点设计了USB应用系统软件部分,包括其外设端的单片机固件程序、主机操作系统上的客户驱动程序以及主机应用程序3部分。最后通过Philips公司提供的PDIUSBD12SMART套件测试电路辅助实现了正常的USB通信,经上位机测试后,能够投入使用。     

航天发射场科研试验场所环境污染物检测分析

为了评价航天发射场科研试验场所的环境质量,确保作业人员的健康和航天科研试验任务的顺利进行,建立了航天发射场科研试验场所总烃和非甲烷烃的气相色谱分析方法,并对航天发射场内多个科研试验场所的环境污染物进行了检测分析,包括甲醛、二氧化碳、苯、甲苯、二甲苯、总挥发性有机化合物、氡、偏二甲肼、二氧化氮、总烃和非甲烷烃等,明确了主要的污染源是甲醛和总挥发性有机化合物,并针对污染状况提出了相应的建议。     

Use of sulfonation procedure for the development of thermally stabilized isotactic polypropylene fibers prior to carbonization

Thermally stabilized isotactic polypropylene fibers were developed using sulfonation procedure prior to carbonization stage. Sulfonation was performed to make the fibers infusible, intractable, and insoluble with concentrated sulfuric acid (approx. 95–97% conc.) at a temperature of 120°C for sulfonation times ranging from 0.5 to 8 h. Sulfonation results in highly crosslinked structures which are thermally stabilized thus making the structure suitable to withstand the high temperatures involved in the carbonization stages. Structural characterization of sulfonated polypropylene fiber was carried out using combination of elemental analysis, differential scanning calorimetry, thermogravimetric analysis, and infra‐red spectroscopy techniques with the aim of following the structural developments at a molecular level. Precursor fibers sulfonated for sulfonation times of 6 h or longer retained up to 46% of their mass at 1000°C. DSC and IR‐spectroscopy observations indicate the gradual loss of isotacticity and crystallinity with the progress of sulfonation treatment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A Double Core-shell Structure Silicon Carbon Composite Anode Material for a Lithium Ion Battery

Silicon - Silicon with high theoretical specific capacity is a promising anode material, but the poor electronic conductivity and excessive volume expansion hinder its practical application. In...     

Elemental imaging via laser ionization orthogonal time-of-flight mass spectrometry

An elemental imaging method using a laser ionization orthogonal time-of-flight mass spectrometer system was developed for the simultaneous detection of all metal and nonmetal elements. The instrument control and data processing were realized by self-developed programs. This system is capable of simultaneous detection of metal and nonmetal elements, with a spatial resolution of 50 μm, the lowest detection limits of 3 × 10(-7) g/g (Li), and a dynamic range of 7 orders of magnitude. Moreover, this technique does not require standards for quantitative analysis and can be a powerful and versatile tool for elemental imaging.     

The effects of using transglutaminase,exopolysaccharide‐producing starter culture and milk powder on the physicochemical,sensory and texture properties of low‐fat set yoghurt

This study focused on the effects of transglutaminase (TGase), exopolysaccharide (EPS)‐producing starter culture or skim milk powder addition on some properties of low‐fat set yoghurt. The incorporation of TGase to yoghurt did not affect the acidity of the experimental samples. However, the proteolytic activity of the starter culture significantly decreased in TGase‐treated yoghurt. Addition of TGase to yoghurt with a low dry matter content (11.08%) resulted in low serum separation and gel firmness and viscosity close to those of yoghurt with a higher dry matter content (14.81%). According to the sensory results, it would be possible to produce an acceptable product with a low dry matter and low fat content using TGase. The results shown that the use of EPS‐producing starter cultures for the purpose of improving the texture properties of low dry matter content yoghurt could not be recommended.     

Efficacy of ε-polylysine, lauric arginate, or acidic calcium sulfate applied sequentially for Salmonella reduction on membrane filters and chicken carcasses

Salmonella contamination continues to be one of the major concerns for the microbiological safety of raw poultry products. Application of more than one decontamination agent as a multihurdle intervention to carcasses in a processing line might produce greater reductions than one treatment alone due to different modes of action of individual antimicrobials. In this study, all possible two-way combinations and individual applications of ε-polylysine (EPL), lauric arginate (LAE), and acidic calcium sulfate (ACS) solutions were evaluated for their effects against Salmonella enterica serovars, including Enteritidis and Typhimurium, using a sterile membrane filter model system. The combinations that provided higher Salmonella reductions were further evaluated on inoculated chicken carcasses in various concentrations applied in a sequential manner. Sequential spray applications of 300 mg of EPL per liter followed by 30% ACS and of 200 mg of LAE per liter followed by 30% ACS produced the highest Salmonella reductions on inoculated chicken carcasses, by 2.1 and 2.2 log CFU/ml, respectively. Our results indicated that these sequential spray applications of decontamination agents are effective for decreasing Salmonella contamination on poultry carcasses, but further studies are needed to determine the effectiveness of these combinations over a storage period.     

λ-Statistical limit points of the sequences of fuzzy numbers

Aytar has introduced the concepts of statistical limit and cluster points of a sequence of fuzzy numbers based on the definitions given in Fridy’s study for sequences of real numbers. In this paper, we define λ-statistical limit and λ-statistical cluster points of sequences of fuzzy numbers and discuss the relations among the sets of ordinary limit points, λ-statistical limit points and λ-statistical cluster points of sequences of fuzzy numbers.     

我国直升飞机用主要非金属材料

介绍了我国直升飞机用主要非金属材料，如复合材料，胶粘剂等，的组成，性能和应用。