Analysis of Ochratoxin A in Wine by High-Resolution UHPLC-MS

A method for determination of ochratoxin A (OTA) in wines using a new-solid phase extraction clean-up procedure followed with ultra performance liquid chromatography (UHPLC)-Orbitrap MS based on two scan events (full-scan Fourier transform mass spectrometer [FTMS] and higher energy-induced collision dissociation[HCD] data-dependent MS/MS) in positive ionization mode has been developed. The limit of detection (LOD) was estimated at 0.46 μg l^?1 for white wine, 0.53 and 0.54 μg l^?1 for rosé and red wines, respectively. The limit of quantification (LOQ) was estimated at 1.57 μg l^?1 in white wine, 1.77 and 1.81 μg l^?1 in rosé and red wines. Recovery experiments were carried out with spiked samples at three concentration levels (2, 5 and 10 μg l^?1). The OTA recoveries in spiked white wine samples varied from 69.6 % to 99.8 %, while the recoveries for rosé and red wine samples were in the range of 63.0–110.2 % and 63.6–103.2 %, respectively. Finally, based on the results, it is concluded that the combination of C18 cartridge with conventional particle packed columns and UHPLC LTQ-Orbitrap XL is an appropriate procedure for OTA analysis in wines.     

超声波测厚时管件夹层缺陷的判定

对使用超声波法在剩余壁厚检测过程中管道夹层等缺陷的筛选进行了分析及讨论.采用网格测量法与分布测量法相结合的方法进行数据分析,即使用网格法测量(测量间距为1 mm),对测得数据使用3维图像模拟厚度分布;然后对厚度变化进行分析,对存在问题的位置选样进行金相分析,确定被检部位出现问题的原因;最后对该方法的拓展应用进行了讨论.     

语文教学应讲一点辩证法

语文教学容易“跟风”,经常“走极端”,已是一个不争的事实。课改初期,强调了人文性,课堂上一度出现了“人文性过度,工具性不足”的倾向,同时也出现“种了别人的地,荒了自己的田”的结果。2011年版《语文课程标准》强调“语文课程致力于培养学生的语言文字运用能力”,近期小语界又出现了唯“语言形式”的倾向,或把“运用”归结为“表达”,或强调以“写作为本位”,或每课都要进行“小练笔”。     

大连金州湾新国际机场运行服务标准化建设初探

摘要：机场作为航空运输服务窗口和“城市名片”其安全保障能力和服务贡量水平将显得允为重要。通过实施服务标准化建设,将标准化渗透到机场运行服务的每一个环节、每一个细节,有助于建主完善的服务质量管理体系,使机场运行管理科学化、服务水平国际化,最终使顾客获得人身的安全、人陆化的服务以及和谐的环境,有利于督促管理者树立科学的发展观,引领机场健康、可持续发展。     

木门产品标准分析与解读

介绍我国木门产品相关标准及企业如何选择适合本企业的标准,对JG/T 122—2000《建筑木门、木窗》检验项目的部分条款进行了分析与解读。     

PCR-CE-SSCP applied to detect cheap oil blended in olive oil

Olive oil adulteration with other cheap oil species has long been upsetting the industry, consumer, and authority around the world. In this article, we first reported the application of PCR-CE-SSCP method to detect other oil species in olive oil. The method was proved to be fast, accurate, reproducible, and interpretation easy. SSCP profiles of 7 oil species were all characterized by single amplicon peak which differentiate olive and the other plants distinctly. The method detection limit was less than 10% of other plant DNA blended with olive DNA. The practical limit for oil was 30–50% refined soybean oil in olive oil.     

Evaluation of the intergranular corrosion in austenitic stainless steel using collinear wave mixing method

Failures due to intergranular corrosion in components of austenitic stainless steel have always been a tough problem in engineering practice. In this paper, the collinear wave mixing was investigated to evaluate the intergranular corrosion in austenitic stainless steel. An acoustic nonlinearity parameter related to the bispectrum, the propagation distance and the amplitudes of fundamental waves in measured signal is proposed. Nonlinear acoustic measurements were conducted on four tubes with different degree of intergranular corrosion. The experimental results demonstrated that the proposed acoustic nonlinearity parameter is sensitive to intergranular corrosion in samples, and is well correlated with the degree of damage.     

焊接工艺对奥氏体不锈钢应力腐蚀行为的影响

针对氯离子环境中奥氏体不锈钢焊缝较高的焊接残余应力极易引发应力腐蚀开裂的普遍性工程难题,对国产304、316L、德国304钢3种材料的不同焊接工艺进行了系列应力腐蚀实验研究.焊接工艺包括手工焊条电弧焊及CO2保护药芯电弧焊、焊后空冷及浇水速冷,取样位置包括母材、焊缝起弧及收弧.通过100多个试样的应力腐蚀对比实验,研究了各种工艺之间的优劣,拟合了2种材料在沸腾氯化镁环境中应力-寿命的数学关系.结果表明,对应力腐蚀寿命而言,316 L是304钢的15倍以上、焊接起弧点高于收弧点、对接焊缝高于角焊缝;焊后速冷工艺可提高焊接接头抗应力腐蚀能力.