Developing On-site,Quick Screening Platform for Artificial Pigments in Food Using Surface-enhanced Raman Spectroscopy

已有研究表明食品加工过程中添加的人工合成色素不仅不能提供营养物质,而且可能是导致小儿多动症的来源之一,影响儿童智力发育.基于表面增强拉曼光谱(SERS)原理和便携式拉曼光谱仪,提出了一种非定向的现场快速筛查方法.该方法只需对疑似含有人工合成色素的固体或液体状食品样品进行简单前处理,即可进行SERS检测.样品前处理和检测的总时长不超过15 min,检出质量浓度在1 mg/L水平,可有效满足政府职能部门的现场执法需求.除具有快速、方便、灵敏度高等特点之外,该检测方法的最大优势在于实现了未知样品的现场非定向测试:在同一种前处理过程和检测方法下,可对食品中常添加的亮蓝、胭脂红、日落黄、柠檬黄、苋菜红和诱惑红6种人工合成色素进行快速鉴定和半定量分析.As widely used additives in food processing,artificial pigments have no any nutrition but are potential sources of hyper-activity and affect the intellectual development of children.On the basis of surface-enhanced Raman spectroscopy( SERS) and portable Raman instrument,we developed a non-targeting,on-site and quick screening platform for artificial pigments in food matrix. SERS measurement could be carried out after the food matrix( either in solid or liquid states) being simply pretreated for 15 min.The detectable concentration is as low as 1 mg / L,a level meeting the demand of the on-site enforcement by the government.Besides the advantages of quick,easy-on-going,and high sensitivity,the most distinguished point of SERS is the non-targeting qualitative on-site detection for the typical pigment additives,including brilliant blue,carmine,sunset yellow,lemon yellow,amaranth and allura red,et al.,while both the pretreatment procedure and the SERS detection remain the same.国家自然科学基金(21473140);; 福建省高校产学合作项目(2016Y4012);; 中央高校基本科研业务费专项(2072016011

Developing fast laboratory screening platform for sulfate dioxide in food by surface-enhanced Raman spectroscopy

基于表面增强拉曼光谱(SERS)的指纹图谱的高能量分辨率,以位于~630; cm~(-1)亚硫酸根的特征峰为定性和定量依据,本文开展了食品中滥用和非法添加二氧化硫的直接检测研究:一种检测流程实现了不同食品基质中二氧化硫的; 高灵敏检测,最低检出浓度达1 mg; kg~(-1)的水平.针对实际样本的传统蒸馏法前处理流程的一些不足以及SERS检测的指纹图谱优势,本文进行了三方面显著改进:; (1)碳酸钙和沸石取代氮气以提高二氧化硫的挥发提取效率; (2)草酸取代盐酸酸化蒸馏溶液,以有效避免挥发性强酸对操作环境的危害;; (3)氢氧化钠溶液代替乙酸铅溶液作为吸收液,以防止二次污染.环境友好、灵敏度高和不受基质干扰等特点使得本方法有望取代经典蒸馏法和比色法,用于食品; 中非法添加二氧化硫类添加剂的快速高效筛查.The direct detection of sulphur dioxide has been realized in various; food matrixes with high sensitivity and high selectivity, on the basis; of the integration of the high energy resolution of the finger-print; spectrum of surface-enhanced Raman spectroscopy and the universal but; easy-on-going pretreatment procedure. The characteristic peak of sulphur; dioxide at ~630 cm~(-1) was applied as the qualitative and quantitative; standard, which displayed a lowest detectable concentration at the 1 mg; kg~(-1) level for the spiked food samples. The key point of the high; sensitivity and selectivity is the effective pretreatment born out of; the standard distillation one, which has been improved in the three; parts. (1) Using CaCO_3 and Zeolite instead of N_2 gas as the bubbling; reagent. (2) Using oxalic acid as the acidic distillation solution to; eliminate the hazards from acid volatilization, such as hydrochloric; acid. (3) Using diluted sodium hydroxide solution as the absorption; reagent instead of lead acetate solution to avoid the secondary; pollution. With the three distinguished advantages of environment; friendly, high sensitivity and free of matrix interference, the proposed; method has great potential to replace the traditional ones for the fast; screening of the illegal or abused sulphur dioxide in food.国家自然科学基金; 福建省高校产学合作项目; 中央高校基本科研业务费专项资

ガイコクジン ビジネス カンケイシャ ノ ニホンゴ シヨウ ジッタイ ト キギョウ カラ ノ ヨウボウ

本稿は、日本で働く外国人ビジネス関係者と在日企業の日本語に対するニーズについて扱うものである.調査は在日企業の人事担当者及び外国人ビジネス関係者を対象に、調査票により実施した.回答を分析した結果 、次のことが明らかになった.1) 日本・合弁企業か外資系企業かによって、日本語の使用状況にかなりの差がある.日本・合弁企業が社内のほとんどのコミュニケーションを日本語で行なっているのに対し、外資系企業における日本語の使用は社内活動の種類によって違いが見られた.会話、読み、書き、いずれも外資系企業のほうが「日本語は使用しない」と回答した割合が高い.2) 日本語使用の実際と今後の希望は、会話力については上昇指向があるが、それ以外の技能に関しては差が見られない.3) 日本語力が採用条件になっているか否かは、外国人ビジネス関係者の母語、採用者側の企業形態によって違う.4) 企業は外国人社員に、顧客とのやりとりよりも、まず社内での日本語運用力を求めている.また、外資系企業の日本語に対する要求度は、日本・合弁企業のそれより大幅に低く、要求の内容にも差異がある.5) 会話、読み、書き、いずれの場合も、企業が期待する日本語力以上の力を外国人社員は発揮している.This paper analyzes how necessary Japanese language skills are at companies in Japan. Two types of questionnaires were prepared. One was for Japanese companies and foreign-affiliated firms, and the other was for non-Japanese businesspeople working in Japan. The following points were investigated, based on the replies to the questionnaire. 1) In which areas do non-Japanese businesspeople use Japanese? What is the difference between their present use of Japanese and their hopes for the future? 2) In which situations do companies expect non-Japanese businesspeople to use Japanese? 3) Is there any difference between the present condition of Japanese use by non-Japanese businesspeople and the expectations of companies? The results are: 1) Japanese language use depends greatly on the type of company for which one works. For example, almost all of the businesspeople in Japanese companies use Japanese for in-house communication, however, language usage in foreign-affiliated firms differs according to the type of work been carried out. In the case of conversation skills only, was there a difference between present conditions and future hopes. 2) Companies expect non-Japanese businesspeople to use Japanese for in-house communication first and then for communicating with customers. Japanese companies expect more non-Japanese businesspeople to use Japanese than foreign-affiliated firms do. 3) For all skills?\conversation, reading, writing-non-Japanese businesspeople use more Japanese than their companies expected

离散正交法(DOM)离散点的正交分析与程序设计

对能够求解一系列线性常微分方程组边值问题的数值计算方法--离散正交法(DOM)进行了离散点的正交分析,给出了计算机实现数值计算的程序设计原理与计算流程图,指出了该方法能够克服传统计算方法由于所求函数的快速增长所引起的边界效应和局部效应的缺点,给出了得到稳定计算过程的可能性.为了推广应用,文中介绍了离散正交法的基本原理、实现方法和求解过程,讨论了采用离散正交法来求解非线性问题的处理方法.并且以承受均布载荷的环形板为例,将采用离散正交法的计算结果与经典解作了对比

飞行人员空晕病112例分析

空晕病又名晕机病,是飞行人员中的常见病,对飞行训练和战斗力均有不良影响,发病率和停飞率较高。现将飞行人员空晕病112例资料分析如下,供防治研究参考。一般资料一、性别:男109名,女3名。二、年龄; 见表1。30岁以下者最多见,占82.1%

具有中间穿透裂纹载流薄板裂纹前缘的应力场

用复变函数方法研究了带有中间穿透裂纹的载流薄板在瞬间电流通入时,在裂纹尖端处由于电流集中及电磁热效应而形成的点热源的计算方法,进而推导并计算了由此热源在裂纹前缘产生的温度场和应力场。通过控制通入电流密度,可以使裂纹尖端温升达到熔化状态,至使裂尖钝化,由温升产生的压应力可以遏制裂纹的扩展。在文中讨论了裂尖附近材料的热传导系数、线胀系数、弹性模量随温度的变化,及其对应力场的影响

两边固支条形薄板的非线性磁弹性效应分析

在给出载流薄板的磁弹性非线性运动方程,电动力学方程的基础上,通过变量代换将描述载流薄板的磁弹性状态方程整理成含有10个基本未知函数的标准柯西(Cauchy)型.并通过差分法及准线性化方法,将标准柯西型的非线性偏微分方程组,变换成为能够用离散正交法编程求解的准线性微分方程组.通过具体算例,得到了两边固支载流条形薄板的磁弹性应力与变形的数值解.变换电磁参量讨论了载流条形薄板的应力及变形的变化规律,通过实例说明了通过变化电磁参量可实现对板的变形控制

载流条形薄板的非线性应力与变形分析

在所建立的载流条形薄板的非线性磁弹性基本方程——运动方程、几何方程、物理方程和电动力学方程的基础上,通过变量代换,整理成含有10个基本未知函数的标准柯西型方程。采用差分及准线性化方法,将含有10个基本未知函数的偏微分方程组,变换成能用离散正交法编程求解的准线性微分方程组。由此计算分析两边简支条形薄板在电磁场和机械载荷耦合作用下的应力与变形,研究侧向电流和外磁场强度对载流条形薄板的磁弹性效应