筘座系统有限元分析

针对无梭织机筘座脚、筘座、钢筘、摇轴的结构特点，建立了筘座系统三维有限元模型。应用软件ANSYS8．0对该模型进行了有限元分析，求出了筘座系统的固有特性。     

同位素稀释-液相/气相-电感耦合等离子体质谱联用等方法为鱼肉中甲基汞成分标准物质准确定值

The fish tissue certified reference material is designed and prepared mainly for evaluating the determining accuracy of methyl mercury in sea fish or other seafood, as well as for a quality control standard. The property value was certified by three different methods, including high performance liquid chromatographic -cold vapor atomic fluorescence spectrometry（HPLC-CVAFS）method and species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS) or gas chromatography (GC-ICP-MS). The experiment included spiking, extraction, derivatization, separation and detection procedures. The ERM 464 tuna fish reference material was used as the analytical quality control standard. The results obtained from three different methods were in good agreement. And the statistic average values were used as certified values of methylmercury in the fish tissue CRM.     

Evaluation of 26Mg stable isotope as an in vivo tracer of magnesium transport for SIMS ion microscopy imaging studies

Isotopic detection with high sensitivity, one of the most important features of ion microscopy, allows the in vivo application of stable isotopes as tracers for unravelling smaller tissue structures implicated with transport capabilities. The evaluation of the mass interferences associated with a particular mass of secondary ion signals is a necessity for tracer studies with stable isotopes. We have tested the feasibility of ²⁶Mg stable isotope as a tracer of magnesium transport in the killifish. The fish were given a single intraperitoneal injection of 3 μmol ²⁶MgCl₂.6H₂O (99.5% ²⁶Mg enrichment), and the renal distribution of ²⁶Mg was examined in frozen freeze-dried cryosections with ion microscopy. High-mass resolution analyses were performed to evaluate the purity of positive secondary ion signals of the nominal masses 24, 25 and 26 in order to assess the purity of ²⁴Mg, ²⁵Mg and ²⁶Mg signals, respectively, in kidneys of control and ²⁶Mg-injected fish. In kidneys of control fish, the purities of ²⁴Mg, ²⁵Mg and ²⁶Mg signals were ≈ 97%, 82% and 90%, respectively. In fish that were injected with ²⁶Mg stable isotope, an enhancement of ²⁶Mg⁺ secondary ion signals was observed with signal purity reaching 95%. These observations indicate that ²⁶Mg can be used successfully as a tracer of magnesium transport in animal models. To uncover the distribution of tracer ²⁶Mg from the naturally abundant background of this isotope, a pixel-by-pixel digital subtraction is applied to the raw ion microscopy mass 26 image.     

HPLC-ICP-MS联机技术与同位素稀释质谱法应用于鱼中甲基汞的分析

The precise determination of methylmercury (MeHg) in fish tissues has been performed by species specific isotope dilution mass spectrometricanalysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS). A labelled MeHg standard (ERM AE670, a Hg 202 enriched methylmercury isotopic reference material) commercial isotope provided by IRMM (Geel, Belgium) was used for these determinations. The experiment procedure included spiking, extraction, and a simultaneous separation and detection procedure. The method gave yield to good precision (<2%). The accuracy of the method has been validated on the certified reference materials BCR 464 (5.50±0.17 mg/kg MeHg) for the tunafish. The result obtained was in good agreement with the certified reference value. And this method was used to do the international comparison CCQM P39.1.     

加工新型矩形齿传剑盘的滚刀基本齿形分析

分析了改型后剑杆织机上的新型矩形齿传剑盘的齿形特点 ,论述了这种传剑盘工作节圆的选取原则 ,采用齿形法线法推导出了加工直线齿形的滚刀刀齿曲线的一般方程 ,采用包络线法推导出过渡凹槽曲线的方程 ,并对过渡凹槽作了分析 ,最后给出一个计算实例     

不同城市居民头发中碳、氮稳定同位素比值特征研究

头发中蕴含了个体的饮食情况等信息,不同地区居民饮食习惯不同,其头发中碳（C）、氮（N）稳定同位素比值也具有一定的差异性。本研究采集了华中、华东、华南、西南和西北地区8个城市常住居民的头发样本,利用元素分析仪 稳定同位素比质谱（EA-IRMS）进行C、N稳定同位素比值检测。结果表明：部分城市间居民头发中C、N稳定同位素比值存在显著差异。居民头发δ¹³C与人均蔬菜消费量呈显著负相关,居民头发δ¹⁵N与人均肉类消费量呈显著正相关,鱼类的大量摄入可能会提高居民头发δ¹⁵N值。男性和女性居民头发中C、N稳定同位素比值没有显著性差异,女性居民头发δ¹³C与年龄呈较弱负相关。中国与其他国家居民头发中C、N稳定同位素比值存在差异,这主要是由不同国家居民的饮食习惯不同导致的。     

超高效液相色谱-四极杆/静电场轨道阱高分辨质谱快速筛查鱼和虾样品中200种药物残留

建立了超高效液相色谱-四极杆/静电场轨道阱高分辨质谱法,快速筛查鱼和虾样品中200种药物残留。取均质后的鱼或虾样品,加入适量0.1 mol/L EDTA-Na₂溶液,分别用乙腈和乙酸乙酯超声提取,经Oasis PRiME HLB通过式固相萃取柱净化,以0.1%甲酸水溶液和0.1%甲酸-乙腈溶液为流动相,Thermo AccucoreaQ色谱柱(100 mm×2.1 mm×2.6 μm)分离;采用Full MS/dd-MS²模式采集数据,利用自建的包含化合物保留时间、母离子和子离子质荷比等信息的数据库定性,一级质谱全扫描母离子定量。结果表明,本方法的检出限为1~50 μg/kg,在不同的加标水平下,200种药物的加标回收率为30%~120%,精密度为5%~30%,其中,精密度在5%~15%、15%~20%和20%~30%的比例分别为70%、10%和20%,且精密度20%~30%主要分布于低加标水平样品。利用本方法对48个鱼和虾实际样品进行筛查,共定性确定9种药物,分别是乙氧喹啉、恩诺沙星、环丙沙星、氧氟沙星、诺氟沙星、甲氧苄啶、磺胺二甲基嘧啶、敌百虫和依维菌素。该方法前处理简单、可同时测定多种药物、检测效率高、筛查定性准确度高。     

一种多功能调节镗杆设计

针对煤矿机械加工、修理中的高精度内孔加工,普遍存在着刀具调整难、效率低、加工精度难以保证的问题,设计了一种多功能调节镗杆。该装置利用结构简单的差动螺机构,通过斜块实现刀具的粗调和微调,达到调整方便,高精、高效。     

四连杆打纬机构的Fuzzy优化设计

设计更好地符合客观实际的四连杆打纬机构,在充分考虑各设计参数的模糊性的基础上,根据模糊方法学的基本理论提出一种模糊优化设计方法,采用使筘座的最大加速度最小,同时使筘座的行程速比系数最大的多目标优化方法,建立了该问题的模糊优化设计的数学模型,并对实例进行了计算与分析,获得最优的综合性能。     

挖槽循环加工方法研究

对用循环编程和用刀补编程并设定刀补值实现挖槽加工进行了论述,对实际生产有一定的指导意义。