加工条件对镀锡铜包钢线导电性的影响

对影响镀锡铜包钢线导电率的因素进行了系统的试验。指出铜的包覆比与铜包钢线的相对导电率近似线性关系；适量的变形可提高镀态铜包钢线的导电性；低温退火可提高铜包钢线的导电性；镀锡层厚度增加使引线的相对导电率均匀下降     

铜泡钢线镀铜生产工艺研究

本文介绍了电解除油、酸洗预镀镍加酸性镀铜的铜包钢线生产工艺参数。ＤＴＪ－１型线材镀铜机具有运行可靠、自动化程度高。本工艺生产的铜包钢线塑性好、表面光洁，适合镀后均匀拉拔变形。     

502^#乳粉罐复合易拉盖的研制

介绍了502^#乳粉罐复合易拉盖的国内外市场情况，实验确定了热熔胶的种类，技术参数，选择确定了镀锡薄钢板，铝箔等主要原材料和产品工艺流程，对市场及经济效益进行了分析。     

对“以简化装置用电解剥离法测定镀锡薄板的镀锡量”方法的几点改进

我们根据江西食品发酵所一九七四年四月编的“镀锡薄板耐蚀性能检测技术资料汇编”中所介绍的“以简化装置用电解剥离法测定镀锡薄板的镀锡量的方法进行了实验,在实验过程中结合我厂的具体条件,对部分仪器及操作方法作了如下的一些改进: 1.用多次反射检流计来代替微步表头,可有效地克服原方法中经常出现甘汞电极失灵,微安表电流变化指示不清楚,致使无测定的现象;     

502~#乳粉罐复合易拉盖的研制

介绍了502#乳粉罐复合易拉盖的国内外市场情况,实验确定了热熔胶的种类、技术参数,选择确定了镀锡薄钢板,铝箔等主要原材料和产品工艺流程;对市场及经济效益进行了分析。     

氨碱法废清液析盐规律的计算研究(Ⅱ)——等密度线

文章计算了废清液蒸发过程中液相组成及密度，在证实计算方法可靠的情况下，对青岛碱厂废清液蒸发过程进行了预测，给出了预测结果，同时计算补充了２０℃Ｎａ＋，Ｃａ∥Ｃｌ－－Ｈ２Ｏ体系的相图数据及等密度线，举例说明了等密度线的应用。     

镀锡钢带镀锡量的测定

介绍用铅盐反滴EDTA滴定法测定镀锡钢带的镀锡量。该法回收率为 99.2 %～ 99.8% ,实物测试相对标准偏差为 0 .35 %～ 1 .36 % ,可以满足科研和产品质量检验要求。本法适用于电镀锡钢带镀锡量的测定 ,热镀锡钢带和镀锡钢丝可参照测试     

螺旋插入物在管内传热与流阻计算机模拟

文章用计算机模拟在管内流体流动的弹簧插入物传热和流动阻力问题，通过二维椭圆方程的数值计算预测流体阻力和传热特性，并根据预测的结果讨论雷诺数和弹簧的线径、螺距对流体摩擦系数和换热系数的影响，为进一步实验确定操作范围和实验条件，对于工业应用具有一定的指导意义。     

试论等速延伸型和等速牵引型强力机测量的关系

本文从理论上分析了等速延伸型强力机和等速牵引型强力机的负载特性,并以棉纱线为例进行了理论计算,找出了两种类型强力机测量结果差异的原因。同时介绍了一种验证理论分析的实验方法和实验结果。     

螺旋插入物在管内传热与流阻计算机模拟

文章用计算机模拟在管内流体流动的弹簧插入物传热和流动阻力问题，通过二维椭圆方程的数值计算预测流体阻力和传热特性，并根据预测的结果讨论雷诺数和弹簧的线径、螺距对流体摩擦系数和换热系数的影响，为进一步实验确定操作范围和实验条件，对于工业应用具有一定的指导意义。     

硫酸亚铁铵体系锌铁合金镀层的性能研究

通过试验研究硫酸亚铁铵体系电镀所得的锌铁合金镀层性能与镀液中添加剂用量之间的关系,介绍试验药品与仪器,镀液的配制方法和配方,电镀试验的工艺流程及参数,以及镀层的检测方法。在温度为30℃,溶液pH值为5.0,电流密度为0.5A/dm2,电镀时间为30min的条件下进行试验。结果表明,随着添加剂用量的增加,镀层变得更加光亮。SEM图显示镀层的微观结构随着添加剂用量的增加更为平整。弯曲法检测结果显示,镀层与基体的结合力随着添加剂用量的增加而增强。对镀层在质量分数为3.5%的NaCl溶液中进行电化学极化曲线测试,得到自腐蚀电位和电流密度,随着添加剂用量的增加,镀层腐蚀电流密度减小,耐腐蚀能力提高。     

铜包钢丝──一种用途广泛的复合材料

概述铜包钢丝的生产方法，分析国内生产存在的问题，介绍产品标准及其应用。     

不同接种方式对食品中热损伤大肠菌群检测的比较研究

目的比较不同接种方式对食品中热损伤大肠菌群检测的影响。方法采用平板计数法、最大或然数法(most probable number,MPN)、表面涂布法、3M Petrifilm~(TM)大肠菌群测试片法、TSA+VRBG计数法等不同的接种方式对热处理食品中受损大肠菌群的检测进行了比较研究。结果平板计数法的结果均为10 CFU/g,MPN法的结果在150~460 MPN/g之间。表面涂布法、3M Petrifilm~(TM)大肠菌群测试片法、TSA+VRBG计数法的结果对数均值和标准差分别为(2.26±0.032)、(2.31±0.026)、(1.82±0.068)。统计分析发现,表面涂布法、3M Petrifilm~(TM)大肠菌群测试片法的检测结果均高于TSA+VRBG计数法,且具有极显著性意义(P0.01),而3M Petrifilm~(TM)大肠菌群测试片法的检测结果又显著高于表面涂布法(P0.05)。结论 MPN法、表面涂布法、3M Petrifilm~(TM)大肠菌群测试片法、TSA+VRBG计数法均适用于热损伤大肠菌群的检测,其中表面涂布法,特别是3M Petrifilm~(TM)大肠菌群测试片法操作简便,且复苏热损伤大肠菌群的效果好。     

锌镍合金电镀在金属制品行业应用探讨

为进一步提高钢丝在各种恶劣环境下的耐腐蚀性能，延长其使用寿命，研究了钢丝电镀锌镍合金工艺和性能。结果表明：镀层中镍含量在１２％～１５％之间时，其镀层钢丝的耐蚀性最好，为锌镀层的３～６倍，镀层经钝化处理后，耐蚀性更好；经反复弯曲、缠绕试验镀层无起皮剥落现象，表明镀层与基体结合牢固，镀层表面结晶细致，银白光亮，可成为镀锌钢丝的又一替代品。建议在钢丝连续电镀生产线上做进一步的中试研究工作，在制品行业推广应用。     

赫尔槽在分析复合镀层故障产生原因中的应用

在电镀工艺管理中,赫尔槽试验因其快捷、简单、对镀液的组成及操作条件敏感,具有良好的试验结果重现性。因此,常用于确定镀液组成及工艺参数,并用于镀液的故障分析,是电镀研究、工艺控制不可缺少的手段。文章介绍了生产实践中,针对金刚石复合镀层特有的故障,用赫尔槽进行分析、判定故障原因及找出解决故障的方法。     

An improved method for the recovery of Salmonella serovars from orange juice using universal preenrichment broth

The relative effectiveness of three methods for the recovery of Salmonella serovars from orange juice was determined. One method, a modified Bacteriological Analytical Manual (BAM) procedure consisted of preenrichment in lactose broth at 35 degrees C for 24 h, selective enrichment, and selective plating. Another method, a National Centers for Disease Control and Prevention (CDC 1) procedure, consisted of direct enrichment in tetrathionate broth at 35 degrees C for 24 and 48 h, followed by selective plating. The third method (also from CDC and designated CDC 2) consisted of preenrichment in Universal Preenrichment (UP) broth at 35 degrees C for 24 h, selective enrichment, and selective plating. In 10 experiments encompassing five different Salmonella serovars and 200 test portions per broth, the CDC 1 method recovered 141 Salmonella-positive test portions, the BAM method recovered 151, and the CDC 2 method recovered 171. In 2 of the 10 experiments, with two different Salmonella serovars, the BAM recovered significantly fewer (P < 0.05) Salmonella-positive test portions than did the CDC 2 method. On the basis of the above results, the second phase of this study focused on a comparison of the effectiveness of the BAM-recommended lactose broth and the CDC 2-recommended UP broth as preenrichment media for the recovery of Salmonella serovars from pasteurized and unpasteurized orange juice. Subsequent culture treatment of the two preenrichments was identical so that the effect of other variables (e.g., different selective enrichment media, various incubation temperatures, and different selective plating agars) on the relative performance of these two preenrichment media was excluded. In one of nine experiments, with pasteurized orange juice, lactose broth recovered significantly fewer (P < 0.05) Salmonella-positive test portions than did UP broth. For the combined results of the nine pasteurized orange juice experiments (180 test portions per broth), lactose broth recovered 99 Salmonella-positive test portions, and UP broth recovered 116. In three of seven experiments, with unpasteurized orange juice, lactose broth recovered significantly fewer (P < 0.05) Salmonella-positive test portions than did UP broth. For the combined results of the seven unpasteurized orange juice experiments (140 test portions per broth), lactose broth recovered 73 Salmonella-positive test portions, and UP broth recovered 117. For both pasteurized and unpasteurized orange juice, the total number of Salmonella-positive test portions recovered with UP broth was significantly greater than the number recovered with lactose broth. These results indicate that UP broth is a more effective enrichment broth for the recovery of Salmonella from orange juice than is lactose broth.     

纳米镍胶体的制备及其在织物化学镀活化中的应用

在酸性条件下,以聚乙烯吡咯烷酮(PVP)为稳定剂,用次亚磷酸钠液相还原硫酸镍,制备出纳米镍胶体,并把该胶体应用于织物化学镀铜的活化工序。用透射电镜(TEM）、扫描电子显微镜( SEM)及X射线衍射仪对该胶体及活化前后织物的进行了表征,结果表明：所得纳米镍胶体成分纯净,粒径分布均匀;浸渍了该镍胶体的织物可以在以甲醛为还原剂的化学镀液中顺利起镀。     

Enumeration of fungi in fruits by the most probable number method

In this study, enumeration methods for fungi in foods were evaluated using fruits that are often contaminated by fungi in the field and rot because of fungal contaminants. As the test methods, we used the standard most probable number (MPN) method with liquid medium in test tubes, which is traditionally used as the enumeration method for bacteria, and the plate-MPN method with agar plate media, in addition to the surface plating method as the traditional enumeration method for fungi. We tested 27 samples of 9 commercial domestic fruits using their surface skin. The results indicated that the standard MPN method showed slow recovery of fungi in test tubes and lower counts than the surface plating method and the plate-MPN method in almost all samples. The fungal count on the 4th d of incubation was approximately the same as on the 10th d by the surface plating method or the plate-MPN method, indicating no significant differences between the fungal counts by these 2 methods. This result indicated that the plate-MPN method had a number agreement with the traditional enumeration method. Moreover, the plate-MPN method has a little laborious without counting colonies, because fungal counts are estimated based on the number of plates with growing colonies. These advantages demonstrated that the plate-MPN method is a comparatively superior and rapid method for enumeration of fungi.     

电镀液对生产厚镀层切割钢丝半成品的影响

钢帘线企业生产切割钢丝或提供电镀黄铜半成品钢丝时,遇到黄铜镀层厚度加厚的问题。分析影响镀层厚度的各个因素:电镀镀层面质量主要取决于电流密度、钢丝浸液长度和运行速度(沉积时间)。选用赫尔槽实验,改变镀液配方,镀铜溶液主要成分P2O74-质量浓度控制在210～230 g/L,Cu2+质量浓度控制在33～36 g/L,其比值控制在6.0～6.8,可确保电镀时最大允许电流密度为18.2 A/dm2,铜层厚度提高10%～25%,满足切割钢丝成品镀层要求,改变了常用的增加镀铜槽长度或降低走线速度的方法,节省投资,提高效率。     

PET-Cu-Sn电磁屏蔽织物面料的制备与性能研究

分别用化学镀铜和电镀锡法在涤纶织物(PET)表面涂覆一层铜/锡合金,通过正交实验和单因素实验法对制备工艺进行优化,对制得的电磁屏蔽织物面料进行结构表征和性能测试。结果表明,优化化学镀铜工艺为:硫酸铜25 g/L,甲醛30 g/L,柠檬酸15 g/L,pH 12,65℃;优化电镀锡工艺为:电压1.5 V,9 min。扫描电镜、能谱分析及XRD衍射结果表明涤纶织物表面可获得较为理想的Sn/Cu复合镀层,锡在化学镀铜层表面形成一层保护膜,抗氧化能力显著增强;牢度测试结果表明复合镀织物具有良好的耐洗性和耐磨性;电磁屏蔽测试结果表明在6.5~10.0 GHz内电磁屏蔽性能均可达71 dB以上,具有优异的电磁屏蔽性能。