气相色谱-负化学源质谱法测定电子电气产品聚合物材料中的卤代磷酸酯阻燃剂

采用丙酮作为萃取溶剂,对电子电气产品聚合物材料中的卤代磷酸酯阻燃剂超声萃取1.5 h后,浓缩、定容、上机。为提高仪器分析方法的选择性,减少前处理流程,选取负化学电离（NCI）模式,在离子源温度210 ℃、甲烷气流量2.5 mL/min条件下对目标分析物进行定性定量分析。结果表明,磷酸三（2-氯乙基）酯（TCEP）和磷酸三（1-氯-2丙基）酯（TCPP）在0.1~10 mg/L浓度范围内,磷酸三（1,3-二氯异丙基）酯（TDCP）和磷酸三（2,3-二溴丙基）酯（TDBP）在0.010~10 mg/L浓度范围内,均有良好的线性关系,相关系数（R²）大于0.999。TCEP和TCPP的检出限和定量限分别为0.010 mg/kg（S/N=3）和0.10 mg/kg（S/N=10）;TDCP和TDBP的检出限和定量限分别为0.001 mg/kg（S/N=3）和0.010 mg/kg（S/N=10）。本方法对空白样品中目标分析物的加标回收率为85.6%~108.9%,相对标准偏差为8.5%。分析了30批次实际样品,包括丙烯腈-丁二烯-苯乙烯共聚物（ABS）、聚氯乙烯（PVC）、印刷电路板（环氧树脂为主要成分）和聚丙烯（PP）等电子电气产品聚合物材料,有2批次检出TCPP,其含量分别为367.5 mg/kg、695.2 mg/kg。可见,电子电气产品聚合物材料中存在一定的卤代磷酸酯阻燃剂污染风险。     

气相色谱质谱联用测定婴幼儿奶粉中香兰素和乙基香兰素

本研究采用了气相色谱质谱测定方法,检测婴幼儿配方奶粉中香兰素和乙基香兰素.通过调节pH值沉淀样品中蛋白和脂肪,采用三氯甲烷溶剂直接提取,简化样品处理过程,并且减少有害物质的使用.同时,本研究优化了气相色谱质谱仪的仪器参考条件,使用PE-5MS色谱柱,本方法回收率达到95％以上.本方法同时具有样品处理简单,检出限低,干扰少等特点,能够较好地满足婴幼儿奶粉中香兰素和乙基香兰素的检测要求.     

气相色谱-质谱法测定纺织品及皮革中9种有机溶剂的残留

建立了气相色谱-质谱（GC/MS）联用法同时检测纺织品及皮革中乙二醇二乙醚（CET）、乙二醇单甲醚(2-ME)、乙二醇单乙醚(2-EE)、乙二醇乙醚醋酸酯(CAC)、N,N-二甲基甲酰胺(DMF)、N,N-二甲基乙酰胺(DMAc)、1,2,3-三氯丙烷（TCP）、N-甲基吡咯烷酮(NMP)和三甘醇二甲醚（TCE）9种有机溶剂的残留量。样品经10 mL甲醇超声提取后,直接由优化好的GC/MS进行定性和定量分析。结果表明,9种有机溶剂校正曲线的线性关系良好（r≥0.999 5）,方法检出限为0.12～0.23 mg/kg。以阴性的棉涤、麻、丝和皮革作为样品基质,分别做3次水平加标回收实验,回收率为81.5%～97.1%,相对标准偏差（RSD）均不大于5.1%。该方法操作简单、分析时间短、灵敏度高、稳定性好,具有实际应用价值。     

GC／MS法测定食品中的3-氯-1，2-丙二醇残留量

水解植物蛋白Hydrolyzed Vegetable Protein(HVP)作为风味剂在食品中使用已有几十年的历史,主要用于方腿、红肠等加工食品中,也用于汤、肉汁混合物风味快餐和固体汤料中。传统的水解植物蛋白的生产工艺,是将植物蛋白质用浓盐酸水解。     

气相色谱-质谱联用法测定水中呋喃丹的研究

建立了气相色谱质谱联用法测定水中呋喃丹的方法。用二氯甲烷革取酸性水样中的呋喃丹、浓缩后加入内标苊-d10，采用气一质联用仪中选择离子监测（SIM）模式进行监测，提取目标化合物的特征离子进行定量，灵敏度高，水中呋喃丹的最低检测浓度可达0．05μg／L；准确度好，样品添加回收率在100、5％～111．0％之间；平行5次进行精密度试验，相对标准差低于6．21％。结果表明：方法简便、快速、准确、重现性好，适合各种水中呋喃丹的测定。     

气相色谱-质谱法测定食品中的3-氯-1,2-丙二醇残留量

本文建立了一个使用GC -ECD和GC MS测定食品中 3 -氯 - 1,2 -丙二醇 (3-MCPD)的方法。本法将试样与Extrelut(经过特殊处理的硅藻土 )拌匀 ,装柱 ,用乙醚取代乙酸乙酯提取 ,经过弗罗里硅土柱净化 ,其中的 3 -MCPD经三氟乙酸酐 (TFAA)在常温下衍生 30min后 ,用配有电子俘获检测器的气相色谱仪和气相色谱质谱联用仪测定。本方法对其净化步骤有很大突破 ,即增加了以弗罗里硅土为层析柱的净化步骤。在Extrelut、弗罗里硅土两次柱净化过程中 ,确定了用一定比例的乙醚 -正己烷预淋洗 ,洗去了大量杂质。用三氟乙酸酐取代了七氟丁酰咪唑 (HFBI)衍生。本法准确、稳定 ,当氯丙醇的添加范围在 0 .0 1- 0 .5 0mg kg时 ,3MCPD的回收率为 80 6 - 117% ,变异系数为 6 5 - 10 1% ,最低检出限为 3μg kg。本方法可适用于肉制品、啤酒、HVP(水解植物蛋白 )、酱油等调味品中的 3 -MCPD的测定     

液-液萃取/气相色谱-质谱法快速测定酱油中的3-氯-1,2-丙二醇

建立了酱油中3-氯-1,2-丙二醇（3-MCPD）的液-液萃取/气相色谱-质谱联用（LLE/GC-MS）检测方法。丁酮作为提取溶剂同时也是衍生试剂。样品加入同位素内标并用氯化钠饱和后用丁酮进行提取,提取液经干燥和净化后加入对甲苯磺酸作催化剂进行衍生。衍生溶液经中和、干燥后用气相色谱-质谱联用仪在选择离子模式下进行测定。3-MCPD在0.008～2.0μg的含量范围内线性关系良好,相关系数（r）为0.999 9,定量限为0.003 mg/kg。在添加水平0.005～0.40mg/kg时准确度为-8.2%～-1.7%,精密度（RSD）1.3%～3.7%。该方法操作简单,检测成本低且灵敏度高,成本低,选择性好,适用于酱油中的3-氯-1,2-丙二醇的快速测定。     

气相色谱-质谱法测定芳烃抽提环丁砜贫剂中烃含量

建立了采用气相色谱-质谱（GC/MS）分析芳烃抽提环丁砜贫剂中各烃组分结构和含量的方法。并使用三因素三水平正交试验来确定最佳色谱分离条件。对芳烃抽提环丁砜贫剂中各烃组分进行定性,对所得质谱谱图解析,并结合质谱标准谱库检索,与各烃组分标准样品保留时间对照,可确定各烃组分结构。以正辛烷为内标物,内标法定量,采用扫描方式分析环丁砜贫剂中各烃组分含量。配制标准溶液,测定各烃组分的相对体积校正因子。样品中各烃组分含量测定的相对标准偏差均小于5%,回收率在91%~109%之间,完成一个样品的分析时间约14 min。与传统的蒸馏法相比,该方法更精确、灵敏、快速、简便,且无环境污染。     

气相色谱-质谱法测定高压汞灯真空度

高压汞灯石英管内惰性气体的填充是保证灯性能的关键因素。本研究采用气相色谱-质谱法测定高压汞灯真空度,测得氩气的相对质量校正因子和氩气/氮气的峰面积比(A_Ar/A_N2),然后根据气体状态方程,计算出灯内氩气压力,并比较5种不同性能的高压汞灯灯管中氩气填充量的差异。结果表明,不同类型的高压汞灯其氩气压力明显不同,而同一类型的高压汞灯内氩气压力值国产的比国外的高,并从惰性气体（氩气）填充量的角度表征了高压汞灯的性能。     

Use of ethyl-dimethyl-2-methoxyethylammonium tris(pentafluoroethyl)trifluorophosphate as base oil additive in the lubrication of TiN PVD coating

This paper discusses and compares the use of ethyl-dimethyl-2-methoxyethylammonium tris(pentafluoroethyl)trifluorophosphate ionic liquid [(NEMM)MOE][FAP] and the traditional zinc dialkyldithiophosphate (ZDDP) as 1 wt% additives to a polyalphaolefin (PAO 6) in the lubrication of TiN PVD coating. Tribological tests performed using a ball-on-plate reciprocating tribometer showed how both additives improve the anti-friction and anti-wear behaviors of the base oil for the two loads tested. However, the traditional additive ZDDP showed the lowest friction coefficient in all cases. Interferometry and XPS analyses showed that the formation of tribofilms resulting from the interaction of the ionic liquid with the surface contributed to the tribological improvement.     

Amorphous calcium phosphate (ACP) in tissue repair process

Synthetic biomaterials submitted to new structural technologies have become ideal for the recovery of traumatized bone tissues and some bone substitutes such as bioactive glass, β‐Tricalcium phosphate (β‐TCP) and amorphous calcium phosphate (ACP) are being used in areas of tissue defects. For this study, ACP was produced in the form of fibers and then submitted to cytotoxicity testing. A sample of ACP was inserted into the mandibular region of a patient with a lost implant so after removal and curettage, the remaining bone site was filled with the ACP biomaterial. Preliminary cytotoxicity test was negative. After 15 weeks of healing, a titanium implant was inserted at the site. Clinical and radiographic follow‐up was conducted for 12 months and sequential radiographic analyses revealed tissue formation resembling spongy bone. Images under immunohistochemistry demonstrated efficient deposition and osteoconduction of the newly deposited tissue. Residual portion of the CaO:P₂O₅ outer layers served as a substrate for osteoid matrix deposition, aiding growth, and the results of fiber absorption favored maturation of the new bone tissue.     

Optimisation of surface roughness on turning fibre-reinforced plastics (FRPs) with diamond cutting tools

Fibre-reinforced plastics (FRPs) are used in structural components in various fields of application of mechanical engineering, such as automobile, biomechanics and aerospace industries. Their own properties, particularly the high strength and stiffness and simultaneously low weight, allows the substitution of the metallic materials in many cases. As a result of these properties and potential applications, exist a great necessity to investigate the machining of these composite materials.This paper presents an optimisation study of surface roughness in turning FRPs tubes manufacturing by filament winding and hand lay-up, using polycrystalline diamond cutting tools. A plan of experiments was performed with cutting parameters prefixed in the FRP tubes. The objective was establishing the optimal cutting parameters to obtain a certain surface roughness (R_a and R_t/R_max), corresponding to international dimensional precision (ISO) IT7 and IT8 in the FRP workpieces, using multiple analysis regression (MRA). Additionally, the optimal material removal rates have been obtained.     

等离子体发射光谱法测定食品级磷酸三钙中铬的含量

采用等离子体发射光谱法测定了食品级磷酸三钙中的铬含量。该方法具有操作简单、快速、准确度,精密度高,检出限低等优点。回收率为92.86%,9次测定的RSD为4.54%。     

PVC保鲜膜中己二酸二乙基己基酯的气相色谱法测定

采用丙酮震荡提取保鲜膜中己二酸二乙基己基酯(DEHA),利用气相色谱氢火焰检测器(FID)进行检测,回收率在96%～101%之间,相对标准偏差在0.87%～1.31%之间.在0.01～5.0 μg范围内线性关系良好,相关系数大于0.999,检出限为0.01%.方法简单快速准确.     

Phosphoryl tris(diethanolamide) (DAP) — A new additive for water-based and ethylene-glycol-based hydraulic fluids and lubricants

A new additive to improve the lubricating properties and rolling contact fatigue resistance of non-flammable water-based and ethylene-glycol-based hydraulic fluids is described. Results of sliding and rolling four ball tests and full-scale pump tests are given.     

High-pressure viscosity prediction of di(2-ethylhexyl) phthalate and tricresyl phosphate binary mixtures using dielectric relaxation data

Dielectric permittivity and loss in di(2-ethylhexyl) phthalate and tricresyl phosphate binary mixtures were measured over a frequency range from 100 Hz to 1.5 MHz under high pressure. The mixtures showed single dielectric relaxation. The composite plots of the dielectric loss data showed one master curve and time–temperature–pressure superposition were applicable. The prediction of high-pressure viscosity was carried out from the change of dielectric relaxation time with temperature and pressure. The predicted results showed relatively good agreement with viscosity data obtained from a falling-sphere viscometer.     

在线消解流动注射光度法测定水中的总磷

使用自行研制的全自动流动注射分析仪,采用在线消解流动注射法测定水中的总磷.方法的检出限为0.008mg/LP;线性范围为0.1-5mg/LP,线性相关系数r为0.9998;其相对标准偏差为0.69%;实际水样的加标回收率为93%-111%;样品测定频率为14样/小时.本方法快速、简便、灵敏度较高,线性范围、精密度和准确度均符合国家标准.     

Mg(OH)2中的硼同位素测定与同位素分馏

We experimented with the incorporation of boron into Mg(OH)₂ during its deposition in magnesium-free artificial seawater with pH values ranging from 9.5 to 13.0. The results indicate that the ¹¹B values of the deposited Mg(OH)₂ were higher than those of the associated artificial seawater. The isotopic fractionation characteristics of boron are distinct from those of inorganic carbonate deposition, and indicate that the mechanism for boron incorporation into Mg(OH)₂ also differs from that of inorganic carbonates.