改良型与传统型免疫亲和柱净化-荧光光度法检测黄曲霉毒素的比较研究

以高效液相色谱法测定食品中黄曲霉毒素作为确证方法,采用改良型免疫亲和柱净化-荧光光度检测技术检测花生及花生制品中的黄曲霉毒素,并与传统型免疫亲和柱净化-荧光光度法进行比较。结果表明：改良型免疫亲和柱净化-荧光光度检测技术具有更好的准确性（检测两个阳性质控样品的标准偏差分别为0.15和1.28）和精密度（相对标准偏差分别为6.65%和8.97%）;在与HPLC方法进行比较时,具有良好的一致性;检测两个加标空白花生样品的回收率分别为102.20%和101.75%。另外,与传统型免疫亲和柱净化-荧光光度法比较,改良型免疫亲和柱净化-荧光光度检测技术操作更为简便,检测时间由传统的25min缩短至10min,大大提高了检测效率。     

免疫亲和柱—荧光分析法测定鲜乳和乳粉中的黄曲霉毒素M1

采用免疫亲和柱-荧光光度法快速测定了鲜牛乳及乳粉中黄曲霉毒素M1.试样经过离心、脱脂、过滤后,滤液经过键合有黄曲霉毒素M1特殊抗体的免疫亲和柱净化,此抗体对黄曲霉毒素M1具有专一的识别能力,黄曲霉毒素M1键合在分离柱中的抗体上.用甲醇/水(1090)将免疫亲和柱上杂质除去,以甲醇/水(8020)通过分离柱洗脱,加入溴溶液衍生,以提高测定灵敏度.衍生化后的洗脱液于荧光光度计中测定黄曲霉毒素M1,检测低限为0.01μg/kg,在0.1-1.0μg/kg范围内,回收率为89.6%-96.1%,变异系数为0.52%-5.8%,分析一个样品的时间小于30min.,分析过程中不使用黄曲霉毒素M1标准物质.用FAPAS的参考标样证实了检测方法、分析仪器和操作人员得到的结果是准确可靠的.本方法具有准确、简单、快速、安全等优点,可以满足少量和批量样品的检测需要.     

进出口中成药中黄曲霉毒素检测方法的研究

[目的] 建立免疫亲和柱-溴化荧光分光光度法检测中成药中黄曲霉毒素总量的常规方法和免疫亲和柱高效液相色谱法检测检测黄曲霉毒素B1、B2、G1、G2的确认方法.[方法] 采用免疫亲和柱(IAC)净化、柱后光化学衍生的高效液相色谱/荧光检测器技术(HPLC/FLD)及溴化荧光光度法(BFS)分别测定两种中成药(水丸和蜜丸)中的黄曲霉毒素B1、B2、G1、G2及其总量.[结果] IAC-HPLC/FLD法平均回收率为86.2%;最低检出限1.0μg / kg;BFS法平均回收率为92.1%;最低检出限1.0μg/kg.[结论] 本方法检测结果尚未发现假阳性现象,假阴性率为零.     

LC/MS/MS测定食品中黄曲霉毒素B1的研究

样品经黄曲霉毒素免疫亲和柱纯化后用LC/MS/MS进行测定,方法简单快速,准确灵敏,抗干扰能力强.本法在添加0.50-5.0μg/kg的黄曲霉毒素B1时回收率为60%～90%,检测限达0.05μg/kg,可满足欧盟最新限量要求.     

高效液相色谱法检测出入境粮谷中的T-2毒素

建立了采用免疫亲和柱净化、柱前衍生、高效液相色谱法结合荧光检测器测定粮谷中T-2毒素的新方法.方法的检测限为0.1 mg/kg,相对标准偏差低于9%,回收率80%～95%.方法简便快速、灵敏准确,满足出入境检验工作的要求.     

高效液相色谱法和荧光光度计法检测花生中黄曲霉毒素的比较研究

比较了两种测定花生中黄曲霉毒素(AFT)的方法--高效液相色谱(HPLC)法和荧光光度计法.以80%甲醇提取样品中AFT,经免疫亲和柱净化,洗脱后,分别以高效液相色谱和荧光光度计检测.结果发现,两种检测方法回收率高,精密度高,检出限均能满足欧盟对花生中AFT最新限量的要求,且两者的结果基本一致.     

免疫亲和柱法测定果仁中黄曲霉毒素

研究了果仁中黄曲霉毒素B1、B2、B1和G2的净化、富集的免疫亲和柱法,并建立了正相高效液相色谱法同时测定这4种黄曲霉毒素的方法,该方法最低检测浓度为01μg/kg,添加回收率为51%～95%.     

芝麻酱中黄曲霉毒素B_1、B_2、G_1、G_2的测定——免疫亲和柱净化光化学柱后衍生-高效液相色谱法

建立了高效液相色谱法同时测定芝麻酱中黄曲霉毒素B1、B2、G1、G2含量的方法。样品用甲醇+水(70+30,V/V)超声提取,免疫亲和柱净化富集,光化学柱后衍生,高效液相色谱荧光法对芝麻酱中黄曲霉毒素含量进行测定,以保留时间定性,峰面积外标法定量。结果表明,样品中黄曲霉毒素B1、B2、G1、G2的检出限分别为0.5、0.2、0.7、0.2μg/kg,线性相关系数>0.999,三个添加水平的回收率均在87.2%~99.4%之间,相对标准偏差为2.88%~5.23%。     

免疫亲和柱净化快速测定油籽和食用植物油中赭曲霉毒素A

针对油籽和食用植物油中可能污染的霉菌毒素-赭曲霉毒素A采用免疫亲和柱净化手段,建立了快速筛选方法(荧光光度法)和确证方法(液相色谱法).本方法在1～50μg/kg添加范围内的回收率为64.7%～120%,符合SN/T0001-1995的规定,可以满足快速、准确检测的需要.     

黄曲霉毒素分析的免疫亲和柱法简介

黄曲霉毒素分析的免疫亲和柱法(IAC-AFLATEST)是美国Vicam维康公司的专利技术,1994年被AOAC(美国公职分析化学家协会)批准为最新的官方方法(编号为:991.31),同时,它也是美国农业部联邦谷物检测中心(证书编号为:FGIS91-103-13)、IUPAC(国际纯粹与应用化学协会)、US-FDA(美国食品药品行政署)和USDA(美国农业部)认证的官方方法.经过山东检验检疫局科技工作者的努力,黄曲霉毒素分析的免疫亲和柱法(IAC-AFLATEST)已经被制定为中国出入境检验检疫局(CIQ)新的行业标准.     

影响脱盐水铁离子含量的原因分析及应对措施

对二级脱盐水系统中铁离子含量超标的原因,如来水水质发生波动、再生剂受到污染、预处理系统操作调整、床体运行切换等进行了论述。并针对上述原因采取了完善水质监测系统、复苏污染树脂、在高效过滤器内部增加防腐、制定床体运行切换曲线等一系列解决措施,最终使二级脱盐水水质能够满足生产要求。     

气相色谱-质谱联用法用于纺织品中富马酸二甲酯的快速测定

本文采用脱水乙酸乙酯对纺织品试样中的富马酸二甲酯进行超声提取,采用气相色谱/质谱联用仪进行定性定量测定,并对超声萃取时间和萃取次数等前处理条件进行了优化,以及进行了线性、回收率、精密度等试验。结果表明：方法线性范围在0.1-50 mg/L,相关系数为0.9988,方法的检测下限为0.05mg/kg,回收率在101%-102%,相对标准偏差RSD（n=7）小于7%。所建方法能很好地应用于纺织品中富马酸二甲酯的检测。     

高效液相色谱法测定蜜饯中乙二胺四乙酸二钠的含量

运用高效液相色谱法测定以蜜饯中乙二胺四乙酸二钠。样品用水溶解,加入氯化铁溶液,采用C18柱分离,以甲醇和0.075 mo L/L KH_2PO_4水溶液进行梯度洗脱,出峰时间定性,外标法定量。结果表明:该方法的乙二胺四乙酸二钠检出限为20 mg/kg,线性范围为2~50μg/m L,相关系数r=0.999 83,回收率为94.2%~97.5%,相关标准偏差(RSD)0.47%。该方法前处理简便、灵敏度高、分离效果好、精确度高和精密度好,对蜜饯中乙二胺四乙酸二钠的含量测定更有针对性。     

高效液相色谱法和高效液相色谱-质谱/质谱法测定荔枝中对氯苯氧乙酸（钠）

建立了荔枝中对氯苯氧乙酸（钠）残留量的液相色谱和液相-串联质谱检测方法,采用碱性水提取,利用二氯甲烷液液萃取进行净化,用液相色谱方法在280 nm检测,检出限为0.02 mg/kg。在负离子模式下进行液质串联质谱检测,检出限为0.01 mg/kg。本方法的添加回收率在78.2%～106.7%,变异系数为2.0%～12.2%。回收率、检测限等技术参数均能满足相关检测要求。本方法应用于65个实验样品的检测,其中有两个样品为阳性,含量分别为0.032 mg/kg及0.026 mg/kg。     

Consumer Reactions to Unethical Service Recovery

Ethical business practices have been widely prescribed, but why? Consumer’s views on unethical business practices have been studied, but possibly more important to marketers and researchers are consumer actions and reactions to unethical business practices and the businesses themselves. Do consumers react negatively, or in such a way as to "punish" the unethical business? If so, what is the nature and extent of the punishment? This research seeks answers to these questions by examining consumer reactions, such as complaining and switching, to instances of unethical business practices. Using equity theory, this research proposes that consumers should be willing to tolerate some unethical behavior as long as they feel their investments and outcomes remain proportionately equal. Consumers who perceive that their outcome/investment ratio is proportionately unequal to their comparison other will respond by switching or complaining. In this research consumers were exposed to two types of service failures with different levels of service recovery in vignettes. Costs incurred by the consumer during the service transaction were also manipulated in the vignettes. Significant differences were found for complaint behavior in the failure recovery vignettes tested. Specifically, voice complaint was higher in the high cost service encounters in both types of services tested. The recovery attempt used (ethical, unethical, or none) led to significance differences in the variables of complaint, voice complaint, satisfaction, and quality. Higher satisfaction and quality ratings were found for the ethical recovery attempt and higher intentions to use complaint and voice complaint in the unethical recovery attempts. One significant interaction between cost and recovery attempt was found. Intentions to use voice complaint were higher in the high cost situations of ethical and unethical recovery, while approaching equality at the no recovery attempt.     

The effects of emotional intelligence on service recovery and organizational loyalty: a case of flight attendants of South Korean airlines

Due to the paucity of empirical studies conducted thus far regarding the effects of flight attendants’ emotional intelligence on service recovery and organizational loyalty, this study examined the relationships among those three constructs. The results of this study demonstrated that emotional intelligence exerted positive effects on service recovery and organizational loyalty, respectively. Namely, flight attendants with a high level of emotional intelligence outperform in service recovery, and tended to be more loyal to an organization. The positive relationship between organizational loyalty and service recovery was also significant. Finally, there was a mediating effect of organizational loyalty between emotional intelligence and service recovery.     

Powerlessness following service failure and its implications for service recovery

This research examines whether service failure in hospitality settings reduces situational power and whether feelings of powerlessness have implications for service recovery efforts. Three studies demonstrated that service failure reduced consumers’ situational power, but only among those with high dispositional power motivation (studies 1 and 2). Moreover, those with high dispositional power motivation evinced greater satisfaction with service recovery efforts that involved status-enhancing compensation as opposed to utility-enhancing compensation (study 2), and when status-enhancing compensation was presented in public as opposed to in private (study 3). These findings suggest that consumers with high dispositional power motivation prefer service recovery attempts that counteract the feelings of powerlessness they experience from service failure. Service managers can benefit from these findings by understanding how feelings of power interact with service recovery efforts.     

The journey from customer participation in service failure to co-creation in service recovery

Customer participation is growing into a widespread phenomenon in the service context. Despite the inherent significance of customer expectations to service failures in the high-participation service context, scant research exists on studying the links among customer participation, customer expectation of service recovery, and service outcomes (e.g., word-of-mouth or WOM). Even more pressing is the lack of research on the type of service recovery that can countervail the inflated customer expectation of service recovery and restore service outcomes. This research demonstrates that high contribution of customers in the beginning of service provision procedure leads to high recovery expectations and low satisfaction. The results also support that co-created service recovery (CCS-R), as contrasted to firm and customer recoveries, has a greater positive effect on satisfaction. Further, the contrasting impacts of each service recovery type on positive and negative WOM are presented. An experiment was conducted using service failure and recovery scenarios. Regression analysis was used to test the hypotheses. The current research has some important implications for scholars and managers who wish to effectively recover failed high-participation service encounters.     

氢化物发生原子荧光光谱法测定彩妆类化妆品中的汞

采用HNO3-H2O2消化样品,用氢化物发生原子荧光光谱法测定彩妆类化妆品中汞的含量。当汞的浓度处于0-10μg/L时,其浓度与原子荧光强度呈良好的线性关系,相关系数为0.9997。回收率为90.65%-98.92%。该方法简便快速,稳定性好,灵敏度高,可广泛应用于彩妆类化妆品中汞的测定。