碱激发玻璃材料

玻璃的结构和组分与粒化高炉矿渣类似,用碱来激发玻璃可获得一种新型的碱激发材料,目前在国内尚无人尝试,其应用有待开拓。着重介绍碱激发玻璃材料的方法及激发的条件。     

European SHINE Taking Breakthrough in Synthetic Rubber Self- recovery Technology

Recently, European SHINE R ＆ D group, focusing on the research and development of synthetic rubber self-recovery technology, made a technological breakthrough. Up to now, SHINE R ＆ D group has achieved the development and production of the new elastomer material in laboratory, has verified all self-recovery features and is preparing for the demonstration project of the pilot scale experiment.     

Growth inhibition of Listeria monocytogenes by bacteriocin-producing Staphylococcus equorum SE3 in cheese models

The anti-listerial activity of Staphylococcus equorum SE3 isolated from cheese brine was tested in two different model cheese systems to ascertain its potential for use as a protective culture for smear cheese ripening. Co-cultivation of Listeria monocytogenes L129 and the antilisterial S. equorum SE3 was performed on “milk agar” or “modified milk agar” (model cheese surface systems). S. equorum inoculated at concentrations of 10⁶ cfu/cm² completely inhibited growth of L. monocytogenes inoculated at 10–500 cfu/cm² on modified milk agar within 24 h of incubation, in the negative controls L129 grew to >10⁷ cfu/cm². At a higher inoculation level, growth inhibition was still more than 7 log units after 24 h. L. monocytogenes strains of different serotypes were also inhibited. Co-cultivation of S. equorum SE3 with other smear bacteria or yeasts, however, showed no growth inhibition of these important ripening microorganisms. The antilisterial effect was not diminished on the modified milk agar when co-cultivation was performed with the added smear cheese microbiota. However, on milk agar with no adjuncts (“green cheese model”), only a slight (<1 log unit) growth inhibition of L. monocytogenes was observed. Addition of peptides or amino acids to milk agar could restore growth inhibition of listeriae at different levels.     

高浓度臭氧水制备系统的研究

使用尼可尼泵-溶气塔组成的臭氧水制备系统,在溶气塔压力为0.25MPa时,使臭氧溶解效率达到90％以上.该系统用于油田回注水的杀菌处理,在接触时间为30min时,臭氧投加量为8.8g/t,硫酸盐还原菌、铁细菌和腐生菌灭菌率可达到中等渗透油藏注入水A2级指标.     

Occurrence and traceability of Listeria monocytogenes strains isolated from sheep's milk cheese-making plants environment

The aim of the study was to conduct an extensive survey on Listeria monocytogenes and Listeria spp. environmental contamination in 13 cheese-making plants. A total of 409 environmental and food samples were collected during years 2011–2013. Listeria spp. contamination was observed in all the facilities, while L. monocytogenes was recovered from 12 facilities with a prevalence ranging between 3.0% and 22.6%. Floor drains were the most contaminated sampling sites (48.8% of positive samples), serving as harbourage site for subsequent contamination. Out of 616 isolates, 277 (45.0%) were Listeria innocua, 274 (44.5%) L. monocytogenes, 41 (6.6%) Listeria ivanovii, 14 (2.3%) Listeria welshimeri and 10 (1.6%) Listeria gravyi. Serotyping carried out by PCR and agglutination method for L. monocytogenes revealed that 169 strains (61.7%) were serotype 1/2a, 65 (23.7%) 4b, 20 (7.3%) 1/2b, 10 (3.6%) 3a, 7 (2.5%) 1/2c and 3 (1.1%) 3b. PFGE conducted on L. monocytogenes isolates using AscI and ApaI restriction enzymes, yielded 6 clusters. Two predominant PFGE clusters were observed including respectively 36 and 32 strains. Within cheese-making plants, L. monocytogenes showed wide variability with strains distributed up to 4 different clusters. Pulsotypes isolated from raw milk filter were never detected in the processing environment, indicating that the contamination originated from sources other than raw milk. The isolation of strains with similar profile from different sampling sites, within and among cheese-making plants, indicated the possible transfer of L. monocytogenes contamination along production lines and from one facility to another. Strains recovered from food were confirmed as originating from the processing environment.     

Factors affecting Penicillium roquefortii (Penicillium glaucum) in internally mould ripened cheeses: implications for pre‐packed blue cheeses

The amount and vivid colour of blue veins of internally mould ripened cheeses are desirable quality characteristics. It is therefore important that there is a sufficient amount of veining and that it maintains its blue appearance to be appealing to consumers therefore leading to maximised sales potential and profit for the manufacturing company. Optimum in vitro growth mimicking the conditions typically found in pre‐packed blue cheeses, and using lactose as the sole carbon source, was facilitated by a gas mixture of 5% oxygen/0% carbon dioxide/balance nitrogen). The work undertaken in this study determined that the factors for optimum in vitro growth of Penicillium roquefortii (strain PRB6) were: a temperature of 20 ± 1 °C, pH of 6.0 ± 0.1, and a relative humidity of 70 ± 0.1%. Further in vitro studies have also shown that the increasing ‘in‐pack’ carbon dioxide concentration not only depresses the growth of P. roquefortii but also affects immature conidiospore pigmentation (no effect has been seen on mature conidiospore pigmentation). The implications of this study suggest that the majority of pre‐packed internally mould ripened blue cheeses on sale in supermarkets are packaged in inappropriate materials. For some cheeses (e.g. the Roquefort‐type cheeses) this is not an issue since these are packed in a much more mature state and some loss of veining colour is not appreciably noticeable.     

预应力高强钢筋混凝土管桩质量通病及防治

通过具体工程实例，分析了预应力混凝土管桩在施工过程中容易出现质量通病的原因，并针对性地提出了具体的预防措施，得出了该桩基工程全部满足设计要求的结论，积累了预应力高强混凝土管桩施工经验。     

真空碳酸钾法脱硫制酸工艺在鞍钢鲅鱼圈的应用

介绍了真空碳酸钾法脱硫制酸工艺概况以及在鞍钢股份有限公司鲅鱼圈钢铁分公司的应用情况。在原设计基础上,对脱硫制酸系统进行了酸气管道、氢氧化钾管道、过程冷却器等局部改进。改进后工艺稳定,接触塔中SO2转化率由原来的97％提高到99％。     

磷酸八钙的制备方法与应用

磷酸八钙是骨、齿的主要成分之一,是羟基磷灰石的重要前驱体,具有良好的生物相容性和生物活性,是较好的骨替换材料。本文综述了磷酸八钙合成研究的最新进展,重点介绍和评述了磷酸八钙的合成与制备方法,分析了各种制备方法的特点,并对其在生物医用材料方面的应用进行了阐述。     

颗粒增强金属基复合材料涂层的制备及其特性与应用

针对复合材料涂层的相关问题, 综述了颗粒增强金属基复合材料涂层的制备技术及其特性的研究进展。重点描述了电热爆炸超高速喷涂技术及电刷镀技术制备颗粒增强金属基复合材料涂层的发展现状、涂层组织结构和力学性能研究进展, 概述了颗粒增强金属基复合材料涂层的工程应用领域及其未来发展方向。