低温密封酸溶——高分辨电感耦合等离子体质谱法测定地质样品中50个微量元素的评价

The method based on the determination of trace elements in geological samples by sector high resolution inductively coupled plasma mass spectrometry with mixed acid digestion procedure has been evaluated. The evaluation show that the results of 29 elements including Li, Cr, Co, Ni, Cu, Zn, Ga, Rb, Y, Cs, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, W, Tl, Bi, Th and U are satisfactory; V, Sr, Nb, Mo, In, Sb, Ba and Pb are acceptable; Sc, Cd, Hf, Ti, Mn, Fe, Ge and Sn have of large deviations, Be, Ta, Zr, As and Se are worse.     

高效液相色谱法同时测定鱼肉中十三种磺胺类药物残留

建立高效液相色谱法测定鱼肉中磺胺嘧啶、磺胺噻唑、磺胺吡啶、磺胺甲基嘧啶、磺胺甲噻二唑、磺胺二甲嘧啶、磺胺氯哒嗪、磺胺甲恶唑、磺胺间甲氧嘧啶、磺胺二甲异恶唑、磺胺喹恶啉、磺胺间二甲氧嘧啶、磺胺甲氧哒嗪等13种磺胺类药物残留量的方法。用C_(18)柱,紫外检测器,流动相为甲醇-1%乙酸溶液,流速1.0mL/min,柱温40℃,于270nm波长处检测。     

以ABS为代表的提高汽车制动性新技术

探讨了提高汽车制动性的新技术;重点介绍ABS（制动防抱死装置）的历史、原理、结构、分类、应用和发展趋势;筒略介绍了ASR、EBD、EHB、ESP、ESS、VDSC等技术。     

影响空间液体润滑的环境因素

概述了影响宅间液体润滑的一些环境因素，包括润滑剂的挥发、挥发速度、粘度、爬移、冷疑，以及缺乏反应物、辐射、原子氧、失重、热传导、宇宙尘和空间杂质等。     

DETERMINATION OF CADMIUM,CHROMIUM, COPPER,IRON, LEAD,AND ZINC IN OYSTERS FROM SOUTHWEST LOUISIANA BY INDUCTIVELY COUPLED PLASMA-OPTICAL EMISSION SPECTROMETRY

This article presents a follow-up, a more comprehensive and extensive study to a previous, but limited study on three metals in oysters from the West Cove area of Lake Calcasieu in Southwest Louisiana. Results from a two-sampling period in mid-October and mid-December 2009 showed concentrations levels in μg/g (mean of 15 oysters, ± standard deviation, and range) as determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) of cadmium, 5.0, ±0.5, 4.0–6.3, and 3.0, ±0.5, 1.8–5.3; chromium, 3.1, ±0.6, 2.0–3.6, and 1.7, ±0.6, 0.7–3.0; copper, 125.0, ±115, 58–245, and 115, ±45, 76–228; iron, 224, ±66, 142–403, and 311, ±111, 160–559; lead, 3.4, ±0.7, 1.6–5.8, and 4.7, ±2.3, 0.7–13; and zinc, 1859, ±774, 740–3471, and 1578, ±783, 692–3056. These concentrations were lower by at least a factor of 10 from the previous study on cadmium and lead but similar to store-bought oysters. The two sampling period concentrations were not statistically different for the two sampling month periods. The lowering of the concentration was attributed to a cleaner (from metals) oyster beds. Results of the six metals from soils in six different sites in the oyster beds showed comparable or slightly higher concentrations than the oysters. Water samples from the six sites were low, or below the detection limit of the ICP-OES instrument.     

Chemical Assessment of Bottled Drinking Waters by IC,GC, and ICP‐MS

Abstract

Bottled water brands, consisting of both local and imported types, collected from Doha city, Qatar, were evaluated for their suitability for human consumption. Water quality constituents that were analyzed include trihalomethanes (THM) by GC‐ECD, turbidity, TDS, total hardness, total alkalinity, pH, EC, major anions by IC, and major cations and trace metals by ICP‐MS. The data obtained were compared with the WHO and the USEPA drinking water standards. As, Se, Ba, and Cu were undetected in all water samples. The levels of potential toxic metals in the studied brands were generally low, except for three brands that had Cd and Pb which exceeded the WHO limits. Fluoride was generally present in all bottled water brands at levels less than the lower optimum level. The reported data for pH, turbidity, TDS, EC, alkalinity, hardness, major anions, and major cations were generally in compliance with the WHO and the USEPA standards, with exception of five brands, where the levels of TDS, EC, F, and NO₃ exceeded the WHO recommended limits. Also, it was found that the concentrations of NO₃ F, Fe, Cr, Zn, and Pb were higher in the local brands. The levels of Cd, Mn, Ca, Mg, EC, alkalinity, SO₄, TDS, THM, and hardness were higher in the domestic brands, when compared to the imported ones. The levels of Cl, pH, turbidity, and Na in the domestic brands were comparable to imported ones. Three THM were found in 29% of water samples with three brands having CHCl₂Br and CHCl₃ levels exceeding the WHO standards.

Comparison of the results of this study with the reported label values of both domestic and imported bottled water showed good agreement with pH and K values, but significant variation for Ca, Mg, F, NO₃, and SO₄ in the imported brands and relatively low variation in the domestic brands. The results of chemical analysis of SRM 1460, trace elements in water, were generally in good agreement with NIST certified values.     

微波消解-电感耦合等离子体质谱法同时测定茶叶中42种元素

建立了电感耦合等离子体质谱法（IcP—Ms）标准模式和优化的碰撞池模式（CCT）结合同时测定茶叶中Li、Be、Mg、Al、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、As、Se、Sr、Mo、Ag、Cd、Sn、Sb、Cs、Ba、Tl、Pb、Bi和16种稀土元素共42种元素的方法。样品经过微波消解,以Ge、In、Re为内标消除基体干扰,通过碰撞池技术消除多原子质谱干扰测定上述元素。对于所测元素校准曲线的相关系数均大于0．9990,回收率范围为90％-110％,相对标准偏差为0．22％-3．97％,大部分元素检出限均小于0．5μg·kg^-1。该方法简便、省时、准确、灵敏度高,适用于实际样品的检测。     

State-of-the-art on theories and applications of cable-driven parallel robots

Cable-driven parallel robot (CDPR) is a type of high-performance robot that integrates cable-driven kinematic chains and parallel mechanism theory. It inherits the high dynamics and heavy load capacities of the parallel mechanism and significantly improves the workspace, cost and energy efficiency simultaneously. As a result, CDPRs have had irreplaceable roles in industrial and technological fields, such as astronomy, aerospace, logistics, simulators, and rehabilitation. CDPRs follow the cutting-edge trend of rigid–flexible fusion, reflect advanced lightweight design concepts, and have become a frontier topic in robotics research. This paper summarizes the kernel theories and developments of CDPRs, covering configuration design, cable-force distribution, workspace and stiffness, performance evaluation, optimization, and motion control. Kinematic modeling, workspace analysis, and cable-force solution are illustrated. Stiffness and dynamic modeling methods are discussed. To further promote the development, researchers should strengthen the investigation in configuration innovation, rapid calculation of workspace, performance evaluation, stiffness control, and rigid–flexible coupling dynamics. In addition, engineering problems such as cable materials, reliability design, and a unified control framework require attention.     

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Huge clusters of embryonic stem cells in human embryos: A morphologic study

Background: Nothing is known about huge clusters (HC) of embryonic stem cells (ESC) in human fetal organs (HFO). Aim: To know the status of HC‐ESC in HFO. Methods: Morphology and immunohistochemistry (IHC) in 32 HFO of 7–40 gestational weeks (GW). Results: HC‐ESC were seen in many HFO including central nervous system, spinal cords, spine, soft tissue, bone, skin, thyroid, lung, liver, pancreas, gall bladder, extrahepatic bile duct, adrenal, kidney, bladder, foregut, midgut, hindgut, female and male genital organs, and neurons. HC‐ESC's were composed of two populations depending on constituting cells. One were large cells with ample acidophilic cytoplasms with vesicular nuclei and nucleoli. The other were small cells with scant cytoplasm with hyperchromatic nuclei without nucleoli, resembling lymphocytes. The HC‐ESC were frequently showed neuronal differentiation. HC‐ESC were positive for NCAM, synaptophysin, NSE, chromogranin, PDGFRA, AFP, ErbB2, bcl‐2, KIT, MET. They were negative for CD45, CD3, CD20, EMA, CEA, CA19‐9, cytokeratin (CK) 7, CK8, CK18, CK19, MUC1, MUC2, MUC5AC, and MUC6. The mean Ki‐67 labeling index (LI) was 13% ± 7%. HC‐ESC showed a little glycogen but lacked mucins. These HC‐ESC were seen in 7–25 GW, and they were rarely seen in 26–40 GW. Conclusions: The morphology, IHC, and ontogeny of HC‐ESC were described. Microsc. Res. Tech. 77:825–831, 2014. © 2014 Wiley Periodicals, Inc.     

极端条件重大承压设备的设计、制造与维护

近年来,随着世界经济形势快速变化、资源品质劣化和能源结构调整,承压设备逐渐向高温、深冷、复杂介质腐蚀、超大容积、超大壁厚等极端方向发展。研究突破极端条件重要承压设备的设计制造与维护关键技术,实现重大装备的国产化并保证其长周期安全运行,成为我国过程装备科技工作者面临的重要课题。阐述过程工业承压设备当前的主要发展趋势,分析以往我国承压设备设计制造与使用管理标准规范和技术方法存在的不足,介绍“十一五”期间我国在高温、深冷、复杂腐蚀、超大容积、超大壁厚等极端条件重大承压设备设计、制造与维护方面所取得的主要成果和解决的若干技术难点问题,对将来需要进一步开展的主要研究工作进行展望。     

Localization of metals in cells of pterygote insects

Insects maintain the equilibrium of their internal milieu by diffusion mechanisms, but more frequently by a substantial storage of metals in the cells of numerous organs: digestive tract, Malpighian tubules, fat body, integument, and genital organs. This storage implies the precipitation, of numerous cations (Ca, Mg, K, Mn, Fe, Zn, Cu) in a structure called the spherocrystal, which originates from the endoplasmic reticulum-Golgi complex: elements precipitate on a glycosaminoglycan nucleus in thin peripheral strata. Some spherocrystals contain exclusively mineral compounds, frequently phosphates, whereas others may contain organic compounds such as urates. In some species mineralized lysosomes store Ca, Fe, Zn, and Cu. When fed additional metals found in the environment, insects such as cockroach and ant are able to stay alive and to trap the metals (Cd or Pb, for example) in the peripheral strata of spherocrystals; the cytoplasm is not altered. It seems that these insects are able to resist exposures to high levels of toxic metals. The lysosomes are able to retain toxic heavy metals (Cd or Hg, for example) within metallothionein-like proteins.     

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Assessment of PM-EDM cycle factors influence on machining responses and surface properties of biomaterials: A comprehensive review

Powder mixed-electro discharge machining (PM-EDM) is recently evolving machining technique which can simultaneously remove and modify the machined surface through thermo-electrical process. It is a modified form of EDM in which the conductive powder elements are added in the dielectric liquid to enhance machined surface characteristics and machining responses. The commonly used biomaterials such as 316L stainless steel, Ti-based alloy, Ni–Ti, Mg alloy, and Co–Mo–Cr alloy have excellent mechanical characteristics while the biofunction of these materials are not in satisfactory level. Due to higher hardness, brittleness, and heat resistant natures of the biomaterials, it is very challenging to machine them with conventional machining. Both the system efficiency and modified surface properties depend on the associated electrical and non-electrical factors of PM-EDM cycle. This review focuses on the influence of process factors such as current, pulse duration, tool-polarity, duty cycle, potential voltage, types of liquid, and added powder concentration on performance outputs including material removal and tool wear rate, coating thickness, coarseness, microhardness, coating adhesion bonding, biocompatibility, and resistant to corrosion. This study also discusses influence of various powders on machining and modified surface characteristics of biomaterials. The future research scopes and challenges of PM-EDM process are included in this study thoroughly.     

[学科发展]润滑研究进展

过去20余年，薄膜润滑、纳米润滑、极端工况摩擦与润滑、生物润滑、绿色润滑、微量润滑等取得了重要进展。最近10余年，超滑、仿生润滑、智能润滑与监测，以及摩擦学测试技术和模拟仿真技术等研究飞速发展。微观研究已经成为润滑研究的主要手段，面向风力发电机、高铁、深空探测、深海探测、大飞机、超高速飞行器、新能源汽车等领域的润滑与密封和绿色近零排放润滑研究已经成为工业界关注的焦点。超滑作为润滑领域的新型颠覆性技术，逐步显示出其在工业生产和人类日常生活中的应用优势与勃勃发展生机。生物润滑包括人类器官中的摩擦与润滑和仿生学研究，在人类健康生活方面展示出重要作用。极端环境（高温、超低温、真空、高压等）摩擦与润滑，在卫星、火箭、舰艇、核电站及其他国防设施上用途广泛。而智能润滑等新兴领域发展，也将智能化应用到润滑领域，为设备的智能运行和制造提供了新的思路。在此，对润滑领域几个重要发展方向，如超滑、薄膜润滑、纳米润滑、极端工况摩擦与润滑、智能润滑、生物仿生学、绿色摩擦与润滑，以及摩擦学测试方法等方面进行回顾，介绍了国内外同行最新研究进展，并对未来进行了展望。     

GC-MS-SIM法同时分析饮料中防腐剂和抗氧化剂

利用离子阱气相色谱-质谱联用仪,优化了色谱、质谱仪器参数,利用选择离子监测（SIM）技术建立了同时检测碳酸饮料、果汁中山梨酸、苯甲酸、脱氢乙酸、叔丁基对苯二酚（TBHQ）、叔丁基羟基茴香醚（BHA）、2,6-二叔丁基对甲酚（BHT）、对羟基苯甲酸甲酯、对羟基苯甲酸乙酯、对羟基苯甲酸丙酯、对羟基苯甲酸丁酯等10种添加剂的方法。方法以10种添加剂的特征离子峰进行定性定量。方法学数据良好,10种添加剂的检测限分别为0.10mg/kg、0.050mg/kg、0.015mg/kg、0.038mg/kg、0.025mg/kg、0.019mg/kg、0.036mg/kg、0.060mg/kg、0.050mg/kg、0.060mg/kg,方法的精密度为2.9%～5.3%、回收率为78%～95%,应用于饮料中食品添加剂的检测,效果良好,检测效率大大提高。     

Immunohistochemical distribution of enkephalin, substance P, and somatostatin in the brainstem of the leopard frog, Rana pipiens

The brainstems of frogs contain many of the neurochemicals that are found in mammals. However, the clustering of nuclei near the ventricles makes it difficult to distinguish individual cell groups. We addressed this problem by combining immunohistochemistry with tract tracing and an analysis of cell morphology to localize neuropeptides within the brainstem of Rana pipiens. We injected a retrograde tracer, Fluoro-Gold, into the spinal cord, and, in the same frog, processed adjacent sections for immunohistochemical location of antibodies to the neuropeptides enkephalin (ENK), substance P (SP), and somatostatin (SOM). SOM+ cells were more widespread than cells containing immunoreactivity (ir) to the other substances. Most reticular nuclei in frog brainstem contained ir to at least one of these chemicals. Cells with SOM ir were found in nucleus (n.) reticularis pontis oralis, n. reticularis magnocellularis, n. reticularis paragigantocellularis, n. reticularis dorsalis, the optic tectum, n. interpeduncularis, and n. solitarius. ENK-containing cell bodies were found in n. reticularis pontis oralis, n. reticularis dorsalis, the nucleus of the solitary tract, and the tectum. The midbrain contained most of the SP+ cells. Six nonreticular nuclei (griseum centrale rhombencephali, n. isthmi, n. profundus mesencephali, n. interpeduncularis, torus semicircularis laminaris, and the tectum) contained ir to one or more of the substances but did not project to the spinal cord. The descending tract of V, and the rubrospinal, reticulospinal, and solitary tracts contained all three peptides as did the n. profundus mesencephali, n. isthmi, and specific tectal layers. Because the distribution of neurochemicals within the frog brainstem is similar to that of amniotes, our results emphasize the large amount of conservation of structure, biochemistry, and possibly function that has occurred in the brainstem, and especially in the phylogenetically old reticular formation.     

摩擦学的进展和未来

在过去的20年内,随着纳米技术的飞速发展和人们社会需求的日益增加,摩擦学迅速发展,并随之产生了几个新的领域,比如纳米摩擦、生物摩擦、超滑、表面织构摩擦学、极端工况摩擦学、微动摩擦学等等。在未来的10年,这些领域和其他新出现的概念,比如:绿色摩擦、纳米制造摩擦学、新型超滑材料和新能源领域摩擦学等等,将在摩擦学研究工作中发挥重要的作用。纳米摩擦学包括纳米尺度下的薄膜润滑、纳米摩擦、纳米磨损、表面黏附等等。绿色摩擦学包括环境友好润滑剂、摩擦噪声的减小、没有环境污染的磨损。生物摩擦学包括人类器官中的摩擦学和仿生摩擦学。超滑包含不同类型的润滑剂,比如类金刚石膜、水基润滑剂、一些生物润滑剂,其具有极低的摩擦因数(0.001量级)。纳米制造摩擦学包括纳米结构制造中的摩擦学、纳米精度制造中的摩擦学和跨尺度(微观、中观和宏观)制造中的摩擦学。这些领域需要不同的理论和技术,以适应不同的制造对象和尺度。极端工况摩擦学包括在重载下、在高/低温度下、在高/低速度下和强腐蚀或氧化环境条件下的摩擦学问题。与表面织构相关的摩擦学理论和技术也是当今发展较快的领域。这些领域的新进展和未来10年的新需求将在下文中具体介绍。     

Mice embryology: A microscopic overview

In this work, we studied the embryology of mice of 12, 14, and 18 days of gestation by gross observation, light microscopy, and scanning electron microscopy. Grossly, the embryos of 12 days were observed in C‐shaped region of the brain, eye pigmentation of the retina, first, second, and third pharyngeal arches gill pit nasal region on the fourth ventricle brain, cervical curvature, heart, liver, limb bud thoracic, spinal cord, tail, umbilical cord, and place of the mesonephric ridge. Microscopically, the liver, cardiovascular system and spinal cord were observed. In the embryo of 14 days, we observed structures that make up the liver and heart. At 18 days of gestation fetuses, it was noted the presence of eyes, mouth, and nose in the cephalic region, chest and pelvic region with the presence of well‐developed limbs, umbilical cord, and placenta. Scanning electron microscopy in 18 days of gestation fetuses evidenced head, eyes closed eyelids, nose, vibrissae, forelimb, heart, lung, kidney, liver, small bowel, diaphragm, and part of the spine. The results obtained in this work describe the internal and external morphology of mice, provided by an integration of techniques and review of the morphological knowledge of the embryonic development of this species, as this animal is of great importance to scientific studies. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.     

辅助指令在数控车床程序编制中的使用技巧

灵活掌握指令的使用,编制出较完善的程序,使经济型数控车床能加工出高质量的零件,是编程中的棘手问题。针对经济型数控车床使用中常遇到的实际问题,在加工轴、孔、球类零件时,使用G00、G92、G26、G27、G29及间隙补偿指令可采用的技巧和注意事项,在提速的同时应充分考虑到指令使用与实际位移轨迹、累计误差、工序安排、运行速度、间补次数等多种因素,使编程简单化的同时提高加工精度,最大效益的发挥经济型数控车床的作用,省时、高效、高质量的完成加工任务。