SOFT TERRAIN SPECTRUM CAUSING VEHICLE VIBRATION

ＳＯＦＴＴＥＲＲＡＩＮＳＰＥＣＴＲＵＭＣＡＵＳＩＮＧＶＥＨＩＣＬＥＶＩＢＲＡＴＩＯＮＳＯＦＴＴＥＲＲＡＩＮＳＰＥＣＴＲＵＭＣＡＵＳＩＮＧＶＥＨＩＣＬＥＶＩＢＲＡＴＩＯＮＺｈｅｎｇＬｉａｎｚｈｕ；ＣｈｅｎｇＹｕｅｓｕｎ；ＬｉｕＭｉｎｇｓｈｕ；ＷａｎｇＤ...     

REGULARITY OF VIBRATION RESPONSE OF MECHANICAL SYSTEM UNDER AFFECT OF VARI-FREQUENCY EXCITING FORCE

ＲＥＧＵＬＡＲＩＴＹＯＦＶＩＢＲＡＴＩＯＮＲＥＳＰＯＮＳＥＯＦＭＥＣＨＡＮＩＣＡＬＳＹＳＴＥＭＵＮＤＥＲＡＦＦＥＣＴＯＦＶＡＲＩ－ＦＲＥＱＵＥＮＣＹＥＸＣＩＴＩＮＧＦＯＲＣＥＲＥＧＵＬＡＲＩＴＹＯＦＶＩＢＲＡＴＩＯＮＲＥＳＰＯＮＳＥＯＦＭＥＣＨＡＮＩ...     

OPTIMUM DESIGN OF HIGH-SPEED RAILWAY LOCOMOTIVE TRACTION GEAR

ＯＰＴＩＭＵＭＤＥＳＩＧＮＯＦＨＩＧＨ－ＳＰＥＥＤＲＡＩＬＷＡＹＬＯＣＯＭＯＴＩＶＥＴＲＡＣＴＩＯＮＧＥＡＲＬｉＬｉｘｉｎｇ；ＷａｎｇＸｉｕｑｉ；ＨｅＷｅｉｄｏｎｇ；ＺｈａｏＷｅｎｚｈｏｎｇ；ＱｉａｎＹｕａｎｍｅｉ（ＤａｌｉａｎＲａｉｌｗａｙＩｎｓｔ...     

RESEARCH OF KINEMATIC CHARAC－TERISTICS FOR QUADRUPED WALKING VEHICLE WITH LEGS OF DIFFERENT DISPOSITIONS OF DOFS

ＲＥＳＥＡＲＣＨＯＦＫＩＮＥＭＡＴＩＣＣＨＡＲＡＣ－ＴＥＲＩＳＴＩＣＳＦＯＲＱＵＡＤＲＵＰＥＤＷＡＬＫＩＮＧＶＥＨＩＣＬＥＷＩＴＨＬＥＧＳＯＦＤＩＦＦＥＲＥＮＴＤＩＳＰＯＳＩＴＩＯＮＳＯＦＤＯＦＳＲＥＳＥＡＲＣＨＯＦＫＩＮＥＭＡＴＩＣＣＨＡＲＡＣ－Ｔ...     

CHINESE JOURNAL OF MECHANICAL ENGINEERING

ＣＨＩＮＥＳＥＪＯＵＲＮＡＬＯＦＭＥＣＨＡＮＩＣＡＬＥＮＧＩＮＥＥＲＩＮＧＣＨＩＮＥＳＥＪＯＵＲＮＡＬＯＦＭＥＣＨＡＮＩＣＡＬＥＮＧＩＮＥＥＲＩＮＧ（ＥｎｇｌｉｓｈＥｄｉｔｉｏｎ）（Ｑｕａｒｔｅｒｌｙ）（Ｓｔａｒｔｅｄｉｎ１９８８）Ｖｏｌｕｍｅ７Ｎｏ...     

IMPROVING ACCURACY OF CNC MACHINE TOOLS THROUGH COMPENSATION FOR THERMAL ERRORS

ＩＭＰＲＯＶＩＮＧＡＣＣＵＲＡＣＹＯＦＣＮＣＭＡＣＨＩＮＥＴＯＯＬＳＴＨＲＯＵＧＨＣＯＭＰＥＮＳＡＴＩＯＮＦＯＲＴＨＥＲＭＡＬＥＲＲＯＲＳＬｉＳｈｕｈｅＺｈａｎｇＹｉｑｕｎＹａｎｇＳｈｉｍｉｎＺｈａｎｇＧｕｏｘｉｏｎｇＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔ...     

PERFORMANCE CHARACTERISTICS AND VISCOUS FLOW ANALYSIS OF CENTRIFUGAL PUMPS

ＰＥＲＦＯＲＭＡＮＣＥＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＮＤＶＩＳＣＯＵＳＦＬＯＷＡＮＡＬＹＳＩＳＯＦＣＥＮＴＲＩＦＵＧＡＬＰＵＭＰＳＰＥＲＦＯＲＭＡＮＣＥＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＮＤＶＩＳＣＯＵＳＦＬＯＷＡＮＡＬＹＳＩＳＯＦＣＥＮＴＲＩＦＵＧ...     

VELOCITY ANALYSIS OF A SPATIALM ECHANISM USING THE PRINCIPLEOF VIRTUAL FORCES

ＶＥＬＯＣＩＴＹＡＮＡＬＹＳＩＳＯＦＡＳＰＡＴＩＡＬＭＥＣＨＡＮＩＳＭＵＳＩＮＧＴＨＥＰＲＩＮＣＩＰＬＥＯＦＶＩＲＴＵＡＬＦＯＲＣＥＳＧｏｎｇＳｈｏｕｃｈｕｎ；ＤａｖｉｄＲｅｄｅｋｏｐＵｎｉｖｅｒｓｉｔｙｏｆＯｔｔａｗａ，Ｏｔｔａｗａ，Ｏｎｔａｒｉｏ...     

STUDY ON EFFECTS OF PHYSICO－AND CHEMICO－PROPERTIES OF MELTING SLAG ON DETACHABILITY OF SSFCE

ＳＴＵＤＹＯＮＥＦＦＥＣＴＳＯＦＰＨＹＳＩＣＯ－ＡＮＤＣＨＥＭＩＣＯ－ＰＲＯＰＥＲＴＩＥＳＯＦＭＥＬＴＩＮＧＳＬＡＧＯＮＤＥＴＡＣＨＡＢＩＬＩＴＹＯＦＳＳＦＣＥＳＴＵＤＹＯＮＥＦＦＥＣＴＳＯＦＰＨＹＳＩＣＯ－ＡＮＤＣＨＥＭＩＣＯ－ＰＲＯＰＥＲＴＩＥＳ...     

INVESTIGATION INTO THE DEGRADATION OF CUTTING FLUIDS IN A WORKSHOP ENVIRONMENT

ＩＮＶＥＳＴＩＧＡＴＩＯＮＩＮＴＯＴＨＥＤＥＧＲＡＤＡＴＩＯＮＯＦＣＵＴＴＩＮＧＦＬＵＩＤＳＩＮＡＷＯＲＫＳＨＯＰＥＮＶＩＲＯＮＭＥＮＴＳｕｌｉｍａｎＳＭＡ，ＮａｂｈａｎＭＢ，ＵｎｉｖｅｒｓｉｔｙｏｆＢａｈｒａｉｎ，ＡｂｕｂａｋｒＭＩ，ＡｍｅｒｉＣｏ...     

Current mass spectrometry strategies for the analysis of pesticides and their metabolites in food and water matrices

Analysis of pesticides and their metabolites in food and water matrices continues to be an active research area closely related to food safety and environmental issues. This review discusses the most widely applied mass spectrometric (MS) approaches to pesticide residues analysis over the last few years. The main techniques for sample preparation remain solvent extraction and solid‐phase extraction. The QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) approach is being increasingly used for the development of multi‐class pesticide residues methods in various sample matrices. MS detectors—triple quadrupole (QqQ), ion‐trap (IT), quadrupole linear ion trap (QqLIT), time‐of‐flight (TOF), and quadrupole time‐of‐flight (QqTOF)—have been established as powerful analytical tools sharing a primary role in the detection/quantification and/or identification/confirmation of pesticides and their metabolites. Recent developments in analytical instrumentation have enabled coupling of ultra‐performance liquid chromatography (UPLC) and fast gas chromatography (GC) with MS detectors, and faster analysis for a greater number of pesticides. The newly developed “ambient‐ionization” MS techniques (e.g., desorption electrospray ionization, DESI, and direct analysis in real time, DART) hyphenated with high‐resolution MS platforms without liquid chromatography separation, and sometimes with minimum pre‐treatment, have shown potential for pesticide residue screening. The recently introduced Orbitrap mass spectrometers can provide high resolving power and mass accuracy, to tackle complex analytical problems involved in pesticide residue analysis. © 2010 Wiley Periodicals, Inc., Mass Spec Rev 30:907–939, 2011     

固相萃取净化-气相色谱-三重四极杆串联质谱法同时测定奶粉中多氯联苯和邻苯二甲酸酯

建立了固相萃取净化结合气相色谱-三重四极杆串联质谱法同时检测奶粉中15种多氯联苯(PCBs)和16种邻苯二甲酸酯类化合物(PAEs)。通过对提取条件、净化方法、仪器条件等进行优化,样品经乙腈超声提取,固相萃取小柱净化后,由程序升温气化进样口不分流进样,选择反应监测模式检测。结果表明:PCBs和PAEs分别在5~1000μg/L和3~1000μg/L范围内呈良好的线性关系,相关系数(r^2)均不小于0.9922;方法检出限分别为0.5~3.0μg/kg和0.3~1.0μg/kg,定量限分别为1.5~8.0μg/kg和1.0~3.0μg/kg;实际样品的平均加标回收率分别为72.4%~94.8%和82.4%~107.1%,相对标准偏差均不大于9.1%(n=6)。该方法前处理简单、净化效果好、灵敏度和准确度高,可以实现对样品的同时净化和提取,能够满足实验室样品中多氯联苯和邻苯二甲酸酯的日常检测要求。     

一种新的液液萃取模式-分散液液微萃取

分散液-液微萃取是2006年才问世的一种新型微萃取技术。它基于使用微量注射器将微升级萃取剂快速注入样液内,在分散剂-水相内形成萃取剂微珠,很大地扩展了有机萃取剂和水样之间相接触面,大大加快了萃取平衡的速度,使目标化合物迅速萃入萃取剂微珠内,提高了萃取效率和富集倍数。萃取富集操作与后续检测方法有很好的相容性,萃取相可直接进样气相色谱、高效液相色谱、薄层色谱、气相色谱-质谱、分光光度、火焰原子吸收光谱和电热原子吸收光谱,对目标化合物进行测定。它不仅适用于痕量有机物的分离富集,也适用于痕量无机金属离子的分离富集,已成功地应用于各种坏境水样(包括高含盐量水样)、多种饮料、生物样品、煤和矿物样品中痕量组分的分离富集,是一种有发展前途的环境友好的分离富集技术。     

质谱直接定量分析技术的应用进展

质谱直接定量分析指待测样品在引入质谱离子源之前,不经色谱分离,直接利用质谱信号对分析物进行含量测定的分析技术。该技术在很大程度上缩短了样品的检测周期,能够满足快速在线、原位分析的需求,目前已在质谱成像、单细胞分析以及在线反应监测等领域展现出广阔的应用前景。本工作综述了与质谱直接定量分析有关的质谱技术、样品处理方法以及相关应用,并展望质谱定量分析的发展趋势。     

固相微萃取-GC/MS法测定水中DDVP

本文运用固相微萃取（SPME）与气相色谱-质谱（GC/MS）联用，对水体中的有机磷杀虫剂2，2-二氯乙烯基二甲基磷酸酯(DDVP)进行了分析。对影响SPME-GC/MS分析灵敏度的各种实验因素如萃取温度、平衡时间、被测组分浓度等进行了讨论。建立的方法不需要浓缩，适于快速、高效地测定水中DDVP。方法的检出限达0.1 μg/L。对董铺水库水样加标进行了DDVP的测定。     

介质阻挡放电电离技术及其应用研究进展

介质阻挡放电电离源是一种非表面接触型的常压敞开式电离源,借助大气压下惰性气体的介质阻挡放电产生稳定的低温等离子体,可在几秒钟内实现液态、固态和气态样品的解吸附离子化,将其用于质谱检测,无需复杂的样品前处理,在常温、常压环境下即可对样品进行原位、实时、快速和无损检测。介质阻挡放电电离源自提出以来发展迅速,现已被广泛应用于食品安全、公共安全、药物分析、环境监测、生命科学等诸多领域。本文综述了介质阻挡放电电离源的发展历程、电离机理、结构分类、影响因素及应用进展,并对其发展趋势进行了展望。     

眼组织中缓释地塞米松药膜的HPLC/MS/MS测定方法研究

眼部手术后 ,在眼组织的前房中植入缓释地塞米松药膜以防术后感染。本实验采用液液萃取、液固萃取的方法来提取生物样品中的地塞米松药物 ,经液相色谱 /质谱 /质谱进行检测 ,样品中药物浓度在 1 0 8— 54μg/L范围内呈现良好的线性 (γ2 =0 .9995) ,最低检测浓度为 0 4 μg/L ,平均回收率大于 77%。用这一方法可高灵敏度、高选择性地应用于临床相关药物的动力学研究     

吸毒者尿样中3-β-D-葡萄糖醛酸吗啡、吗啡、O~6-单乙酰吗啡和可待因的LC-MS/MS分析

建立吸毒者尿样中3-β-D-葡萄糖醛酸吗啡、吗啡、O6-单乙酰吗啡、可待因的液相色谱-串联质谱分析方法。尿样经固相萃取后,用C18液相柱分离,以含甲酸铵和甲酸的水、乙腈为流动相等度洗脱,采用电喷雾电离(ESI+),多反应监测(MRM)模式检测目标化合物。以化合物的保留时间、2对母离子/子离子对定性,尿样中3-β-D-葡萄糖醛酸吗啡的检测限为0.5μg.L-1,吗啡、O6-单乙酰吗啡、可待因的检测限为0.1μg.L-1;线性关系良好,相关系数r在0.998以上;日内及日间精密度均在10%以内。该方法快速、灵敏、简便、可靠,能同时分析吸毒者尿样中的3-β-D-葡萄糖醛酸吗啡、吗啡、O6-单乙酰吗啡和可待因。     

Application of mass spectrometry in the analysis of polybrominated diphenyl ethers

This review summarized the applications of mass spectrometric techniques for the analysis of the important flame retardants polybrominated diphenyl ethers (PBDEs) to understand the environmental sources, fate and toxicity of PBDEs that were briefly discussed to give a general idea for the need of analytical methodologies. Specific performance of various mass spectrometers hyphenated with, for example, gas chromatograph, liquid chromatograph, and inductively coupled plasma (GC/MS, LC/MS, and ICP/MS, respectively) for the analysis of PBDEs was compared with an objective to present the information on the evolution of MS techniques for determining PBDEs in environmental and human samples. GC/electron capture negative ionization quadrupole MS (GC/NCI qMS), GC/high resolution MS (GC/HRMS) and GC ion trap MS (GC/ITMS) are most commonly used MS techniques for the determination of PBDEs. New analytical technologies such as fast tandem GC/MS and LC/MS become available to improve analyses of higher PBDEs. The development and application of the tandem MS techniques have helped to understand environmental fate and transformations of PBDEs of which abiotic and biotic degradation of decaBDE is thought to be one major source of Br_1‐9BDEs present in the environment in addition to direct loading from commercial mixtures. MS‐based proteomics will offer an insight into the molecular mechanisms of toxicity and potential developmental and neurotoxicity of PBDEs. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:737–775, 2010     

多壁碳纳米管净化-超高效液相色谱-串联质谱技术同时测定牛奶中青霉素类药物残留

研究了多壁碳纳米管净化-超高效液相色谱-串联质谱技术同时测定牛奶中的羟氨苄青霉素、青霉素V、氨苄青霉素、苯咪青霉素、甲氧苯青霉素、青霉素G、苯咪青霉素、邻氯青霉素、乙氧萘青霉素和双氯青霉素药物残留。样品用乙腈沉淀蛋白,提取液用磷酸缓冲液稀释后,经改性的多壁碳纳米管材料净化,通过Waters C18色谱柱分离,以乙腈和10 mmol/L乙酸铵（pH 4.5）溶液为流动相进行梯度洗脱,采用电喷雾-正离子多反应监测模式检测,内标法定量。10种青霉素药物在相应浓度范围内的线性相关系数均大于0.99,方法的定量限在0.1～10.0 μg/kg之间。在低、中、高3个浓度添加水平下,10种青霉素药物的平均回收率为72.0%～110%,相对标准偏差在1.83%～9.33%之间。多壁碳纳米管材料具有较好的净化效果,该方法可以快速、准确地测定牛奶中的青霉素类药物残留。