红外加热技术在荧光灯生产（排气工艺）中的应用

荧光灯组装工艺流程中,存在着一系列影响灯管质量问题的因素,如材料质量、零件化学处理、热加工工艺、真空卫生条件等,这些因素的影响最终将在排气工序中反映出来。排气工序中的温度和时间两大要素,是制灯行业感到难以掌握的技术问题。目前制灯行业的加热装置中所采用的气体火焰加热和电阻丝直接加热,都存在着烘箱温度不易控制达到所需工艺温度和上下温差悬殊等弊病。本文提出将远红外加热技术应用到排气烘箱加热装置中,从实践中证实了其可行性,并收到了明显的经济效益和社会效益。     

Viability assessment of lactic acid bacteria in commercial dairy products stored at 4 °C using LIVE/DEAD® BacLightTM staining and conventional plate counts

The viability of lactic acid bacteria (LAB) from commercial fermented milks was studied during storage at 4 °C. The enumeration of total viable bacteria was assessed using fluorescence microscopy. Plate counting on selective media was used to enumerate LAB. Using LIVE/DEAD® BacLight^TM viability staining, it was observed that bacterial counts decreased gradually after expiry dates, the number of viable bacteria remaining above 10⁶ bacteria g^?1 for all of the products. Viable cell counts estimated by plating onto selective media were lower than those obtained by direct microscopic counting. The viability of LAB contained in acid products decreased during their storage period at 4 °C. All products contain viable LAB ranging from 10⁸ to 10⁹ bacteria g^?1 and could be considered as probiotic, given that the recommended minimum number of probiotic bacteria in such food products is approximately 10⁷ bacteria mL^?1 product. The number of bifidobacteria in commercial fermented milks declared to contain bifidobacteria varied from 10⁴ to 10⁷ bacteria mL^?1. This study confirms the usefulness of fluorescent techniques for a rapid and accurate evaluation of bacterial viability in probiotic products.     

无电极放电灯的发展动态

无电极放电灯是新一代电光源，具有结构简单、无电极、高光效、高显色性能和长寿命等特性，已发展成为无电极荧光灯、无电极金属卤化物灯和微波硫灯等几种类型。本文主要介绍这些无电极放电灯的发光原理、放电类型、灯的结构、特性和发展动态。     

Monitoring pH-dependent conformational changes in aqueous solutions of poly(methacrylic acid)-b-polydimethylsiloxane copolymer based on fluorescence spectra of pyrene and 1,3-bis(1-pyrenyl)propane

Aqueous solutions of poly(methacrylic acid)-b-polydimethylsiloxane copolymer (PMA-b-PDMS), and reference solutions of PMA homopolymer, were studied as a function of pH using fluorescent probes: pyrene (P) and 1,3-bis(1-pyrenyl)propane (P3P). In both polymers the conformational transition of PMA chains at pH>5 was reflected in the sharp increase of the intensity ratio of the first to the third vibronic band in emission spectra of P; an excimer emission appeared for P3P, as well as for P if the probe concentration was higher than its solubility limit in water. The excimer to monomer intensity ratio of both probes is a sensitive indicator of the conformational transitions of polymer chains, but P3P is significantly more sensitive compared to pyrene. The data clearly indicated that the presence of PDMS blocks markedly facilitated the transition, even though the ratio of dimethylsiloxane to methacrylic acid units in the copolymer was low, 1:34. The absence of the P3P excimer emission at pH≈3 was rationalized by assuming that clustering of sections of PMA chains around pyrene moieties imposes an extended conformation of the probe molecule.     

Fluorescent solar concentrators. Experimental results

A physical characterization is presented for classes of selected fluorescent substances, with special emphasis on their concentration in the support. The influence of climatic factors was analyzed from two points of view: spectral and structural. Two types of geometrical models of fluorescent solar concentrators have been obtained : plates and cylinders.     

基于Web Services的网络测量系统的研究与实现

在分析现有网络测量系统的基础上。文章实现了一个基于Web Services技术的网络测量系统，具有良好的可扩展性和可伸缩性．并且针对IPv6协议的出现开发了相应的测量模块，可以同时测量IPv4网络和IPv6网络的性能。     

等熵系数和雷诺数对四孔楔型探针气动测量影响的研究

用4孔楔型气动探针在一个特殊的试验风洞里测量了不同工质和不同工况下的参数。对大量试验数据进行分析，得出等熵系数和雷诺数对气动测量的影响，并进一步定量分析它们对在风洞中标定探针确定各个参数的影响，从而提出在标定探针和气动测量过程中有指导意义的结论。     

Synthesis and spectral properties of axially substituted zirconium(IV) and hafnium(IV) water soluble phthalocyanines in solutions

Methods of synthesis of novel water soluble axially substituted Zr(IV) and Hf(IV) phthalocyanines with gallic, 5-sulfosalicyllic, oxalic acids, and methyl ester of gallic acid as axial ligands coordinated to the central atom metal of phthalocyanine are presented. The absorption spectra of complex solutions in various solvents were characterized. The dependence of the spectral red shift from Reichardt’s empirical polarity parameter is described. The deviation from the linearity of Beer–Bouguer–Lambert law was investigated for the range of concentration 5×10⁻⁶ to 10×10⁻⁵ M. Fluorescent properties of axially substituted phthalocyaninato metal complexes in DMSO solutions were investigated.     

一种高稳定度的石英晶体微量天平

介绍一种频率稳定度优于0．3Hz的石英晶体微量天平，在微量天平的电路中采用了高稳定度（5×10-9／d）的时基振荡器，探头采用热丝或半导体致冷器件恒温结构，频率稳定度优于0．3Hz。用此天平成功地测量了三元盐氧化物阴极和钪酸盐阴极的蒸发率，并对真空镀铝膜厚度进行了精确监控。     

圆锥形接触式激光刀头设计

本文用展开法设计圆锥形接触式激光刀头,导出了刀头几何参数的计算公式。给出了一个设计实例并讨论了各几何参数之间的关系。