有限元在身管与药筒高压接触变形计算中的应用

本文针对自动武器中药筒和身管变形的变间隙、变锥度的特点,构造了身管和药筒的截面环等参元分析模型,并据此建立了相应的增量形式的弹塑性有限元求解方程．针对贴膛不同时刻的特点,在身管和药筒上配置了配点对,应用变形协调条件,编制了药筒和身管高压间隙变形的有限元求解程序．并给出了数值计算实例．     

切缝药包爆破模型及生产试验研究

应用脉冲全息干涉及动光弹测试技术,通过切缝药包烘破模型试验,分析了切颖药包爆破断裂成缝机理,并在此基础上进行了生产试验,试验结果表明,采用切缝药包爆破可以精确地控制岩石断裂方向。     

电感耦合等离子体质谱(ICP-MS)法测定玻纤滤筒中金属元素本底值的预处理方法探讨

探讨了不同预处理方法对国产玻纤滤筒本底值的降低效果,便于废气样品的分析测定。分别对空白滤筒、热硝酸、硝酸+硫酸和硝酸+EDTA、HCl处理后的滤筒进行分析,测得滤筒中金属元素的含量;对处理效果较好的一批滤筒进行空白加标,考察加标回收率,全程用电感耦合等离子体质谱(ICPMS)法对样品进行测定,结果发现空白滤筒中部分金属元素含量较高;热硝酸处理后,滤筒本底中铅含量有所降低,但其它元素去除效果不显著;硝酸+硫酸处理后,滤筒中铅含量剧增;硝酸+EDTA处理滤筒,铅可以得到较好的去除效果,大部分金属元素含量有了明显降低;基于HCl对金属有较好的溶出效果,浸泡可较好地降低滤筒中金属元素的含量,但大量氯离子存在对ICP-MS法测定的干扰较大。对硝酸+EDTA处理后的滤筒进行空白加标,大部分金属元素加标回收率75%。故以硝酸+EDTA处理玻纤滤筒可以使国产玻纤滤筒适用于废气样品的分析。     

超高效液相色谱-串联质谱多目标分析沉积物中的微量有机紫外线吸收剂

利用超声波辅助萃取、通过硅胶柱层析法净化,联合超高效液相色谱-串联质谱技术建立了同时检测沉积物中12种微量有机紫外线吸收剂的定性定量方法.优化了萃取条件,比较了净化过程中硅胶活化温度、洗脱剂种类和体积对回收率的影响.样品在甲醇中经超声波辅助萃取3次,每次15 min;硅胶活化温度为160 ℃,洗脱剂为甲醇/二氯甲烷混合液(1∶1,V/V);质谱采用大气压力化学电离源正离子模式,数据采集为选择反应监测模式.目标物的回收率为55％～118％,方法定量限为1～ 250 pg/g,有效控制了基质干扰.采用本方法初步分析了珠江广州城市河段表层沉积物中的有机紫外线吸收剂,除UV-327外,其它目标物均被检出,含量最高可达12.0 ng/g(干重).     

High‐performance liquid chromatographic cartridge with gradient elution capability coupled with UV absorbance detector and mass spectrometer for peptide and protein analysis

We discuss the construction and performance of a high‐performance liquid chromatography cartridge that we developed that resulted from a culmination of previous research. We have recently developed an innovative approach to creating gradient elutions using dual electroosmotic pumps and a series of three valves. This method has been proved to be the most reproducible and robust in producing gradients compared to our previously tested methods. Using this approach, we have assembled a high‐performance liquid chromatography cartridge powered and controlled via a computer. We have successfully coupled the cartridge with an ultraviolet absorbance detector and a mass spectrometer for separating complex protein/peptide samples. The cartridge is readily coupled with other detectors such as electrochemical detector and laser‐induced fluorescence detector.     

3种小口径步枪弹的致伤效应

探讨小口径枪弹的杀伤性能,将SS109 5.56mm、M74 5.45mm、87式5.8mm等3种小口径步枪弹结构特点、性能参数及明胶中运动规律进行了对比评测;以明胶为组织模拟物开展了步枪弹侵彻靶标实验,并对3种步枪弹侵彻明胶实验数据进行对比分析。分析结果表明,我国87式5.8mm普通弹杀伤性能优于SS109 5.56mm和M74 5.45mm步枪弹,较好验证了理论分析结果。     

Application of silica-based monolith as solid phase extraction cartridge for extracting polar compounds from urine

The silica monolith with ionizable silanol groups and large surface area was found able to function as an offline cation exchange solid phase extraction (SPE) cartridge for extracting polar analytes. The prepared cartridge was housed in a 2-mL syringe fixed over a SPE vacuum manifold. The unique property of this silica monolithic cartridge was demonstrated by extracting epinephrine, normetanephrine and metanephrine from urine samples. These analytes were chosen as model compounds for testing because of their high hydrophilicity, and being candidates monitored for clinical diagnosis. The extracted analytes, after concentration and reconstitution were then quantitated by high-performance liquid chromatography coupled to mass spectrometer (HPLC/ESI/MS). Multiple reactions monitoring was carried out with transitions: 184 → 107, 184 → 134 and 198 → 148 for analyzing epinephrine, normetanephrine and metanephrine, respectively. The limit of detection was 3 ng/mL for metanephrine and 5 ng/mL for normetanephrine and epinephrine. The relative standard deviations of measurements ranged from 2 to 10%. The sorbent offered good linearity with coefficient of determination (r²) > 0.99, over a concentration range of 20-200 ng/mL. The relative recoveries ranged from 60 to 67%, 55 to 59% and 99 to 105% for epinephrine, normetanephrine and metanephrine, respectively. The prepared cartridge had shown potential and was found robust in extracting the polar analytes repeatedly without any significant loss in efficiency.     

缓冲层介质对切缝药包爆破断裂力学行为影响的研究

为了研究炸药至炮孔壁之间的缓冲层介质对切缝药包爆破断裂力学行为的影响,采用新型数字激光动态焦散线测试系统,开展多组爆破光测实验。借助LS-DYNA数值模拟软件,对比分析炮孔内部压力场的分布规律。研究结果表明:切缝药包能够利用切缝管有效控制爆炸应力场的分布,使能量沿切缝方向集中释放,定向爆破效果显著。与空气相比,水提高了切缝药包对炮孔壁的冲击破坏能力,爆生主裂纹的断裂力学参数增大,表现为更长的扩展距离、更高的运动速度和动态应力强度因子。爆炸冲击波能和爆生气体脉动能是水中主要的能量存在形式,模拟结果显示水比空气具有更好的传压能力,缓冲层内形成更高的压力峰值。     

化学改性纤维素亲和膜色谱用作人血清白蛋白中杂质的去除

用环氧法对纤维素微孔滤膜进行了化学改性，并在经改性的膜上共价结合了活性红染料配基Ｋ－２ＢＰ，设计并制作了特殊的膜分离器，利用所制备的亲和膜分离器成功地去除了人血清白蛋白中的杂质。