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111.
有关增长爆发力的训练,国内外学说观点多见,可在理论上尚未形成一个完整的概念,本文以文献资料和基础理论进行综告分析,着重从运动生理学角度探讨增长爆发力的机制,使其在理论上尽早形成一十完整概念,尽快寻找增长爆发力的最佳途径,为科学地安排爆发力训练提供理论依据。  相似文献   
112.
本文从火工技术领域中的几个方面,提出开展理论和实验研究意见,例如:关于灼热桥丝式电火工元件,延期火工药剂,传爆系列的可靠性;动力火工元件的能量输出等,试图通过对有关问题的论述,对火工技术发展方向提出概括性建议。  相似文献   
113.
本文从生理学和生物物理学的角度就无氧功率、力量和速度的关系一一进行分析讨论,并提出爆发力训练中在注重速度发展的同时应以力量的发展为重点之建议。  相似文献   
114.
Pan X  Zhang B  Cobb GP 《Talanta》2005,67(4):816-823
An efficient extraction and cleanup technique, and an instrumental detection method suitable for determination of trace amounts of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and its nitroso-metabolites in animal liver tissue were developed and validated in this paper. The method includes the extraction of explosives from liver tissue samples using accelerated solvent extraction (ASE) followed by cleanup using florisil and styrene-divinyl benzene (SDB) cartridges to remove interfering naturally endogenous compounds. The instrumental analysis was conducted using a capillary column gas chromatograph coupled with an electron capture detector (GC-ECD). High recoveries (58.9-106.8%) of RDX, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX), hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX), and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX) were achieved at all concentrations studied. RDX, MNX, and TNX gave higher recoveries than DNX at all three tested concentrations (50, 250, 1250 ng/g). Overall recoveries of RDX, MNX, DNX, and TNX from 1 g beef liver samples containing 50, 250, and 1250 ng/g were 80.1, 82.8, 68.9, and 80.4%, respectively. The optimal injection port temperature range was 160-170 °C for analysis of RDX and its nitroso-metabolites. Higher or lower temperatures than 160-170 °C decreased signal amplitudes. RDX was unstable in the liver extraction matrix; as much as 50% of RDX was degraded 10 days after extraction if keeping the liver sample extracts at room temperature. Degradation of RDX to MNX, DNX, or TNX was not detected during the sample storage, extraction, or instrument analysis processes. Other optimized extraction and GC conditions are also discussed.  相似文献   
115.
Hopper KG  Leclair H  McCord BR 《Talanta》2005,67(2):304-312
A novel electrolyte has been developed for the simultaneous separation of cations and anions in low explosive residue by capillary electrophoresis. This electrolyte contains 15 mM α-hydroxyisobutyric acid (HIBA) as the buffer, 6 mM imidazole as the cation chromophore, 3 mM 1,3,6-naphthalenetrisulfonic acid (NTS) as the anion chromophore, 4 mM 18-crown-6 ether as a cation selectivity modifier, and 5% (v/v) acetonitrile as an organic modifier. The pH was adjusted to 6.5 using tetramethylammonium hydroxide (TMAOH), an electroosmotic flow modifier. The method was optimized by varying the concentrations of α-HIBA, imidazole, and 1,3,6-NTS at three different pH values. The results provided a simultaneous indirect photometric analysis of both anions and cations with detection limits ranging from 0.5 to 5 ppm for anions and from 10 to 15 ppm for cations with a total run time of under 7 min. The method was then applied to the analysis of Pyrodex® RS and black powder, as well as several smokeless powders. The results obtained were consistent with previously reported results for separate anion and cation analysis and provide a faster, more complete analysis of each sample in a single chromatographic run.  相似文献   
116.
Wang J  Lu F  Macdonald D  Lu J  Ozsoz ME  Rogers KR 《Talanta》1998,46(6):1405-1412
Screen-printed carbon electrodes have been developed as disposable voltammetric sensors for 2,4,6-trinitrotoluene (TNT). Thick-film electrodes based on various conventional and modified inks have been compared for this task. The operation is based on placing the selected thick-film carbon sensor in the non-deaerated/quiescent sample and using a fast (<1 s) and sensitive square-wave voltammetric scan. Different experimental variables have been optimized to yield a detection limit of 200 ppb TNT and a wide linear range. The high selectivity, demonstrated in assays of various untreated environmental samples, is attributed to the facts that the reducible nitro group is rare in nature and that most electroactive organic compounds require higher potentials. The new single-use sensor strips should facilitate the on-site environmental screening of TNT.  相似文献   
117.
本文指出:对于加工数量很少的大型工件,采用无模爆炸成型工艺是很经济的。试验初步结论是:先用圆片形药包爆炸成型,再用环形药包校形,其边皱长度约在板料直径的十分之一。当采用锥形药包时,初步试验表明:校形后可基本清除边皱现象。文章还给出了有关的经验公式。研究工作未涉及材料变薄率和大型工件各次成型之间的退火问题。  相似文献   
118.
炸药、生物及化学危险物检测在反恐和公共安全领域具有重要应用价值,也是目前亟需解决的问题。激光诱导击穿光谱技术利用高能激光脉冲诱导材料产生等离子体,通过探测等离子体辐射光谱从而分析其组成成分。拉曼光谱技术是基于非弹性光散射的一种光谱检测方法,可以反映分子的振动信息。由于它们都具有快速和非接触遥测的优点,成为最有发展潜力和应用前景的危险物检测技术。介绍了激光诱导击穿光谱、拉曼光谱以及二者联合探测技术在危险物检测中的国内外发展现状,并对各自的优缺点进行了分析。激光诱导击穿光谱信号强、实时性好,但重复性差、基底效应影响显著,在判别组成元素相同而分子结构不同的危险物和干扰物时面临巨大挑战。拉曼光谱能够提供被测物的分子信息,适合于鉴别有机危险物,但信号弱、受荧光干扰大、检测低浓度样品及分析混合物的能力弱,外场使用时受周围杂散光以及环境变化的影响大。将这两种光谱探测技术相融合,发挥各自的优点,可以有效地提高探测危险物的准确度。但两种光谱联合探测系统结构和数据处理复杂,成本高,还有许多技术难点亟需解决。文章最后,对危险物激光诱导击穿光谱和拉曼光谱研究的前景进行了展望。  相似文献   
119.
黄帅 《科学技术与工程》2012,12(6):1321-1324
本文针对分离的方案要求,建立相应的分离体六自由度数学模型,相对运动模型,并对一级、二级在分离过程中是否发生碰撞进行仿真分析。同时考虑了爆炸螺栓未正常爆炸的情况下,给二级带来的影响。仿真结果表明当有一个爆炸螺栓未爆炸时,利用二级发动机推力对一级的反作用力将爆炸螺栓拉断,一二级会发生碰撞。在此基础上,基于各个爆炸螺栓未爆炸一二级分离碰撞时间的不同,分析得出爆炸螺栓的分布密度。  相似文献   
120.
The prediction of the penetration of three-dimensional (3D) shaped charge into steel plates is a challenging task. In this paper, the smoothed particle hydrodynamics (SPH) method is applied to simulate the jet formation generated by the shaped charge detonation and its damage to steel plates. The Jones–Wilkins–Lee (JWL) equation of state (EOS), Tillotson EOS, and elastic–perfectly plastic constitutive model were incorporated into SPH for the modeling of explosive detonation and dynamic behavior of metal material. The compute unified device architecture (CUDA) parallel programming interface has been employed in SPH to improve the computational efficiency of SPH. Firstly, the constitutive models and EOSs are validated by 3D TNT slab detonation and aluminum–aluminum (Al–Al) high velocity impact. Then the jet formation of the shaped charge detonation and its penetration into the steel plates are investigated using the graphics processing unit (GPU)-accelerated SPH methodology. The numerical results of these test cases are compared against the published experimental data or analytical result, which shows that the GPU-accelerated SPH methodology is capable of tackling the 3D shaped charge detonation and penetration involving millions of particles with high computational efficiency.  相似文献   
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