应用灰色聚类分析评价服装压力的舒适性

将3种不同氨纶含量的单面针织面料做成9种试样进行人体穿着试验,得出了服装压力舒适性的主观感觉量值.运用灰色聚类分析对这9种试样进行分类,并且利用MATLAB对计算过程进行了程序化.     

服装压力舒适性的灰色聚类分析

介绍了灰色聚类分析的一般方法。将3种不同氨纶含量的单面针织面料做成的9种试样,进行人体穿着试验并得出服装压力舒适性的主观感觉量值,运用灰色聚类分析对9种试样进行分类。并且利用MATLAB对计算过程进行了程序化。     

针织双点黏合衬在高档西服应用中的黏合工艺

随着高档西服向"轻、薄、柔、挺、舒"方向发展,针织双点黏合衬的使用越来越广泛.生产中黏合衬的选用及其黏合效果是影响服装质量的重要因素之一.为了研究高档西服面料和针织双点黏合衬的最优黏合工艺,选择了4种轻薄型精纺毛织物和4种针织双点黏合衬进行一一组合形成16种试样,采用正交方法设计筛选了9种黏合工艺参数组合,分别在9种工艺条件下黏合后进行试样洗涤前后的剥离强度测试,洗涤后的尺寸变化率测试和外观质量评级,得到了各种试样最优的黏合工艺及匹配性.     

织物热湿舒适性能评价指标的灰色理论研究

选用珍珠纤维、莫代尔纤维、大豆纤维、竹纤维、聚乳酸纤维等新型再生纤维及普通棉共9种针织内衣织物进行对比实验.使用GB/T 11048-1989平板式保温仪法与GB/T 12704-1991透湿杯法等常规方法对试样进行测试,得出各试样的热湿舒适性能指标,并与ISO 11092出汗热板仪法测出的试样热阻、湿阻结果进行了比较...     

架空管道常用涂层防腐性能试验研究

采用中性盐雾试验方法模拟架空管道使用环境,对20钢无缝管道试样进行连续喷雾试验,比较了工程中6种常用防腐涂层防腐性能。结果表明：收缩带和环氧粉末与聚乙烯复合涂层试样防腐性能较好,正黄色氯磺化聚乙烯和双层熔结环氧粉末涂层试样防腐性能其次,单层熔结环氧粉末试样和红丹银粉涂层试样防腐性能较差。图9参14     

大豆蛋白纤维交织物的保健性能研究

为探明纬纱中大豆蛋白纤维含量和织物组织对织物的负离子、抗紫外线和远红外性能的影响,文章以涤纶丝作为经纱原料,大豆蛋白纤维与黏胶纤维作为纬纱原料,试织了两个系列共14种不同规格的织物试样.其中,9组为大豆蛋白纤维含量不同而组织相同的试样,5组为大豆蛋白纤维含量相同而组织不同的试样,并测试了14组试样的负离子、抗紫外线和远...     

稀释倍数对食品包装纸中高锰酸钾消耗量的影响

目的研究稀释倍数对食品包装纸中高锰酸钾消耗量测定结果的影响。方法样品经浸泡前处理后,采用滴定法对多个试样不同稀释倍数下的高锰酸钾消耗量进行测定,进而确定不同滴定体积试样的稀释范围。结果滴定体积大于10 mL的试样,需要稀释5倍以上;滴定体积在9～10 mL之间的试样,需要稀释2～5倍;滴定体积7～9 mL之间的试样稀释需要1～2倍。滴定体积在约9 mL的试样稀释不得超过5倍,滴定体积约10 mL的试样稀释不得超过10倍,滴定体积在7～9 mL之间的试样稀释不得超过4倍。结论煮沸时出现褪色现象的试样需要稀释后测定,稀释倍数对高锰酸钾消耗量影响很大,要选择合适的稀释倍数才能测得准确的结果。     

天然染料姜黄应用于几种常见纤维染色的研究

应用姜黄色素对几种常见纤维进行染色,并选用6种不同的媒染剂,对染色后各纤维试样进行媒染,最后测试和评定了各纤维试样的耐洗色牢度.结果表明,姜黄色素对这几种纤维染色可获得深浅不同的黄色,蛋白质纤维羊毛和蚕丝染得了较为深浓的土黄色；而纤维素纤维棉、亚麻和粘胶染得了较为浓艳的橘黄色.此外,不同媒染剂媒染处理的纤维试样颜色也有所不同,大多会不同程度地偏向这些媒染剂在水溶液中所呈现的色泽；而媒染处理后,各染色试样的耐洗牢度也均有不同程度的提高.     

白水处理对机械浆纸张性能的影响效果

该文研究了不同净化和未净化模拟水试样对纸张性能的影响.实验中使用了三种造纸厂中较普遍的白水试样,即未漂TMP白水试样、连二亚硫酸盐漂白TMP+PGW水试样、过氧化漂白PGW水试样.这些水试样中亲脂性抽出物、半纤维素、果胶、木素及盐类物质的含量是不相同的.分别使用高粘度PAC或Fennofix对水试样进行净化以此来模拟白水的净化.实验净化及未净化水试样抄片后,对其进行性能检测,以便确定它们对纸张性能的检测.研究结果表明有效除去白水中亲脂性抽出物能够增加纸张的抗张强度和白度.过氧化漂白水试样中亲脂性抽出物的有效除去后纸张的抗张强度从20Nm/g增加至30Nm/g.模拟水试样中高含量木材组分能够增加滤水时间,尤其是未漂模拟水试样.     

基于保留指数原理结合气相色谱-三重四极杆质谱法快速筛查蔬菜中农药残留的方法研究

目的 建立气相色谱-三重四极杆质谱联用法快速筛查蔬菜中农药残留的方法.方法 利用正构烷烃C9-C33标准溶液,结合气相色谱-三重四极杆质谱联用仪及其Smart Database Pesticides数据库建立仪器数据采集方法.选用9种农药为目标物,试样经QuEChERS方法进行萃取净化后,建立质谱多反应监测(multi...     

兰州市市场上部分食品铅污染状况分析

为了解兰州市部分市售食品的铅污染状况，检测了抽检和送检的样品558份，其中冷饮195份，118份检出铅，检出率60．5％。17份超标，超标率8．72％。糕点类食品75份，39份检出铅，检出率52％，超标8份，超标率10．67％。调味品48份，43份检出铅，检出率89．58％，超标1份，超标率2．08％。蜜饯、糖果51份，43份检出铅，检出率84．31％，无超标。酒类50份，29份检出铅，检出率58％，2份超标，超标率4％。干果、坚果139份，123份检出铅，检出率88．49％。从检测结果看，虽然铅检出率较高，但是大多数符合国家标准。建议我国的铅食品卫生标准与CAC标准靠拢。这既有利于广大消费的食用安全，也有利于我国食品参与国际竞争。     

分子生物学技术在一起食物中毒检测中的应用

应用分子生物学技术对一起食物中毒样品进行检测,提高实验室应对食物中毒快速检测和溯源分析能力。方法 应用实时荧光PCR技术对一起食物中毒10份患者粪便和6份可疑食品进行快速检测,并对39份粪便和8份食品进行病原培养分离鉴定,应用PCR技术对分离菌株进行invA毒力基因检测,PFGE及MLST基因分型技术对分离菌株进行同源性分析,并与其他地区菌株进行遗传学差异对比。结果 10份患者粪便和6份可疑食物经实时荧光PCR检测均为沙门菌阳性,从39份粪便和8份食品中共分离到31株肠炎沙门菌。PFGE及MLST分析显示31株菌具同源性,表明食物和患者分离菌株基因型别一致,MLST分型显示本次分离株与其他地区优势克隆有同源性,31株肠炎沙门菌均具有invA毒力基因。结论 实时荧光PCR技术应用于食物中毒病原检测,缩短了病原检测周期,提高了检测的准确性,PFGE及MLST两种基因分型技术可对病原菌进行溯源分析,对于掌握病原菌流行规律具有重要意义。     

Muscle protein changes post mortem in relation to pork quality traits

The relationship between post-mortem traits of muscle proteins and water loss traits was investigated using 84 pork loins representing the four quality traits of PSE, RSE (reddishpink, soft, exudative), RFN (reddish-pink, firm, non-exudative) and DFD. Protein solubility measurements (sarcoplasmic, myofibrillar and total) were lower and myosin denaturation (quantified by myofibrillar ATPase activity) was higher for PSE samples compared with samples from the other quality classes. RSE samples were similar to RFN samples in protein solubility and myosin denaturation, although RSE had lower values then DFD samples for protein solubility measurements. RFN samples had lower drip, thaw, cook and total water loss than RSE samples and all water loss traits were lowest for DFD samples and highest for PSE samples. Insoluble phosphorylase was the only characteristic that differentiated among PSE, RSE and RFN samples. SDS-PAGE and Western blots indicated that in PSE and RSE samples, the myofibrillar protein titin was less degraded and nebulin was more degraded compared with RFN and DFD samples. SDS-PAGE of extracted and unextracted myofibrils showed that the reduced myofibrillar solubility of PSE samples was caused by decreased extractability of the myosin heavy chain in these samples. In conclusion, although RSE samples have unacceptably high water loss, muscle protein denaturation was minimal and did not explain the low water-holding capacity.     

基于衰减全反射傅里叶变换红外光谱的餐饮废油掺假检测

为了建立基于衰减全反射傅里叶变换红外光谱(ATR-FTIR)的餐饮废油掺假检测方法,以常见食用油和餐饮废油为原料,收集8个餐饮废油和25个食用油样品,制备30个掺假油样品,共63个油样进行红外光谱扫描。随机取48个油样作为校正集样品,15个油样作为验证集样品,建立餐饮废油定性分析模型,并对定性模型进行验证;从30个掺假油样品中,随机取20个油样作为校正集样品,10个油样作为验证集样品,建立餐饮废油定量分析模型,并对定量模型进行验证。结果表明:在红外光谱范围为1 550~650 cm-1条件下,采用原始光谱结合判别分析建立定性分析模型,其识别率可达100%;采用偏最小二乘法(PLS)建立定量分析模型,在掺假比例1%~10%时,模型预测值与实际掺假比例呈良好的线性关系,相关系数(R)为0.982 2,标准偏差(SD)为0.47。表明基于ATR-FTIR的餐饮废油掺假检测是可行的。     

Pesticides and heavy metals levels in Egyptian leafy vegetables and some aromatic medicinal plants

A total of 835 samples of leafy vegetables and some aromatic medicinal plants were collected from five different areas of Egypt during 1999. Ninety-seven per cent of the leafy vegetables were contaminated with heavy metals with 39% exceeding the maximum limits for each element. Cadmium was detected in 78 of 116 samples of leafy vegetable, although without any exceeding the maximum limits. However, lead was detected in 99 samples, of which 39 exceeded the maximum limits (0.3 mg kg^-1) and 56 medicinal plant samples of 70 had lead levels above 0.5 mg kg^-1. Copper was detected in 69 medicinal plant samples, of which 58 samples contained levels higher than 10 mg kg^-1. However, cadmium was only found in 43% of samples with only two of 70 samples above the maximum limit. Seventy-three per cent of the samples of medicinal plants were contaminated with pesticide residues, of which 44% contained amounts that exceeded maximum residue limits. Malathion was the most frequently found pesticide residue, being detected in 203 of 391 (52%.) samples, followed by profenofos, which was detected in 131 of 391 (33%) samples.     

The development of imitation crab stick containing chicken breast surimi

Imitation crab stick samples were made from Alaska pollack with Golden treadfin bream surimi (C), Alaska pollack with Golden treadfin bream surimi and spent laying hens breast surimi (T1), Alaska pollack with spent laying hens breast surimi (T2), and Alaska pollack with Golden treadfin bream with mechanically deboning chicken meat (MDCM) (T3). Crude protein was significantly lower in T2 and T3 compared with C and T1. However, crude fat and carbohydrate were not significantly different among the samples during storage periods. pH steadily increased until 2 weeks of storage thereafter pH was decreased in all samples. Lightness (L^∗) and whiteness (W) were significantly lower in T3 than those of other samples. In fatty acid composition, the amount of polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was higher than other fatty acids in all samples at 0 week of storage period. TBARS (thiobarbituric acid reactive substances) value was highest in control sample compared with other samples. In sensory evaluation, color was the highest in C than other samples, whereas T3 was lowest in color than those of other samples. Overall acceptability was significantly highest in T1 compared with other samples during the storage periods.     

稻米中多氯联苯及多溴联苯醚残留及风险评估

通过分析稻米样品中指示型多氯联苯(PCBs)和12种代表性多溴联苯醚(PBDEs)的存留状况及含量水平,通过膳食风险评估,阐明PCBs和PBDEs在稻米中的安全风险。稻米样品粉碎后,采用直接提取法–酸性硅胶净化法对样品进行前处理,通过气相色谱–串联质谱法对其中7种指示型PCBs和12种代表性PBDEs进行同时检测。45个稻米样品中,PCBs的检出率为42%,合计含量水平在0～78pg/g干重之间,稻米中PCBs主要检出单体为PCB-28和PCB-52,特征符合我国多氯联苯的生产历史情况;仅在一个样品中检出PBDEs,合计含量为41 pg/g干重。稻米中的PCBs和PBDEs污染水平低,经过风险评估,其未造成稻米的食品安全风险。     

氨基甲酸酯类农药残留质控样品的制备与评价-以灭多威为例

目的 建立一种蔬菜冻干粉中氨基甲酸酯类农药残留质控样品的制备方法并对制备技术进行评价。方法 以圆白菜为基质, 灭多威为目标物, 采用真空冷冻干燥, 基质添加的方式制备质控样品。采用液相色谱-串联质谱法对质控样品中目标物含量进行测定。通过随机抽样测定以评估样品的均匀性, 通过观察样品12个月内目标物检测结果变化以评估样品的稳定性。结果 本方法制备的灭多威质控样品均匀性和稳定性良好。蔬菜冻干粉质控样品便于贮藏、运输且在常温下能够长期稳定保存。样品中灭多威的制备值与测得值较好吻合。结论 本研究确立了蔬菜冻干粉中灭多威质控样品的制备方法, 所建立的制备技术可以确保质控样品定值结果的准确性, 为氨基甲酸酯类农药残留质控样品制备方法的开发提供技术支持。     

Aniline in vegetable and fruit samples from the Canadian total diet study

An isotope dilution method based on solvent extraction followed by GC–MS analysis was developed and used to determine aniline in vegetable and fruit samples collected from the Canadian total diet study. Aniline was not detected in any of the 23 vegetable samples from the 2005 total diet study at a method detection limit of 0.01 mg kg^–1. Among the 16 fruit samples, it was detected only in apple samples, with an average concentration of 0.278 mg kg^–1. Aniline was not detected in apple samples collected in the 2002, 2003, 2006 or 2007 total diet studies, but it was detected in the apple samples collected from the 2001 and 2004 studies, at concentrations of 0.085 and 0.468 mg kg^–1, respectively. The average aniline concentration for the 2001, 2004 and 2005 apple samples was 0.277 mg kg^–1. Good repeatability of the method was observed with replicate analysis of apple samples, with relative standard deviations (RSD) ranging 3.8–21% and an average of 11%.     

Detection of Salmonella from chicken rinses and chicken hot dogs with the automated BAX PCR system

The BAX system with automated PCR detection was compared with standard cultural procedures for the detection of naturally occurring and spiked Salmonella in 183 chicken carcass rinses and 90 chicken hot dogs. The automated assay procedure consists of overnight growth (16 to 18 h) of the sample in buffered peptone broth at 35 degrees C, transfer of the sample to lysis tubes, incubation and lysis of the cells, transfer of the sample to PCR tubes, and placement of tubes into the cycler-detector, which runs automatically. The automated PCR detection assay takes about 4 h after 16 to 24 h of overnight preenrichment. The culture procedure consists of preerichment, enrichment, plating, and serological confirmation and takes about 72 h. Three trials involving 10 to 31 samples were carried out for each product. Some samples were spiked with Salmonella Typhimurium, Salmonella Heidelberg, Salmonella Montevideo, and Salmonella Enteritidis at 1 to 250 cells per ml of rinse or 1 to 250 cells per g of meat. For unspiked chicken rinses, Salmonella was detected in 2 of 61 samples with the automated system and in 1 of 61 samples with the culture method. Salmonella was recovered from 111 of 122 spiked samples with the automated PCR system and from 113 of 122 spiked samples with the culture method. For chicken hot dogs, Salmonella was detected in all 60 of the spiked samples with both the automated PCR and the culture procedures. For the 30 unspiked samples, Salmonella was recovered from 19 samples with the automated PCR system and from 10 samples with the culture method. The automated PCR system provided reliable Salmonella screening of chicken product samples within 24 h.