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1.
Results of shock-dispersed-fuel (SDF) explosion experiments are presented. The SDF charge consisted of a spherical 0.5-g PETN booster surrounded by 1 g of fuel, either flake aluminum (Al) powder or TNT. The charge was placed at the center of a sealed chamber. Three cylindrical chambers (volumes of 6.6, 20, and 40 l with L/D = 1) and three tunnels (L/D = 3.8, 4.65, and 12.5) were used to explore the influence of chamber volume and geometry on completeness of combustion. Detonation of the SDF charge created an expanding cloud of explosion product gases and hot fuel (Al or TNT). When this fuel mixed with air, it formed a turbulent combustion cloud that consumed the fuel and liberated additional energy (31 kJ/g for Al or 15 kJ/g for TNT) over and above detonation of the booster (6 kJ/g) that created the explosion. Static pressure gauges were the main diagnostic. Pressure and impulse histories for explosions in air were much greater than those recorded for explosions in nitrogen—thereby demonstrating that combustion has a dramatic effect on the chamber pressure. This effect increases as the confinement volume decreases and the excess air ratio approaches values between 2 and 3.5.  相似文献   
2.
The use of capillary column gas chromatography and gas chromatography/mass spectrometry for the analysis of a series of standard solutions (0.1 to 10 μg/ml) of 2,4,6-trinitrotoluene (TNT) and eight other nitroaromatic components was evaluated. The techniques included gas chromatography with electron capture detection (GC/ECD), full scan and selected ion monitoring gas chromatography/mass spectrometry with electron impact ionization (EI/FS and EI/SIM), full scan and selected ion monitoring gas chromatography/mass spectrometry with positive ion chemical ionization using methane reagent gas (PICI/FS and PICI/SIM), and full scan and selected ion monitoring gas chromatography/mass spectrometry with negative ion chemical ionization using methane reagent gas (NICI/FS and NICI/SIM). The performance of the techniques was comapared by determining the linear response range, precision, and detection limits of the analyses.  相似文献   
3.
通过Heck—SonogashFT—IRa偶合法合成了含五蝶烯(Pentiptycene)基团的新型荧光共轭聚合物——聚对苯撑乙炔撑衍生物(PPE),分别为:侧链不对称烷氧基取代的PPE1和侧链单、双一丙基七异丁基多面体齐聚倍半硅氧烷(POSS)取代的PPE2、PPE3。采用FT—IR、^1H—NMR、UVVis、荧光发射光谱、TGA等仪器对PPE的结构和性能进行了分析测试,并研究了其与TNT之间的荧光响应。结果表明:PPE1、2、3均表现出良好的荧光性能及较高的荧光量子产率;对TNT显示出很高的猝灭敏感性,其荧光猝灭效率与TNT的浓度曲线表现为非线性关系,特别是侧链引入POSS的PPE2,提高了PPE的荧光量子产率及与TNT荧光猝灭效率,同时,PPE的热稳定性得到明显提高。  相似文献   
4.
刘素红  夏攀  张成功  张立  郭寅龙 《有机化学》2014,(10):2135-2139
以爆炸条件下溶菌酶的反应产物为研究对象,运用基质辅助激光解吸-飞行时间质谱的方法研究其反应产物与不同炸药的反应特征性.结果显示,雷管的使用不会对溶菌酶有影响,而在有爆炸物爆炸的条件下,除了正常溶菌酶酶解多肽信号外,一些[MH+17]+,[MH+18]+,[MH+28]+,[MH+32]+和[MH+44]+的加合峰信号也能被检测到.这可能是在炸药爆炸过程中产生的一些活性小分子(如NH3,H2O,CO/N2,O2,CO2)与溶菌酶发生反应得到的反应产物.不同炸药生成的活性小分子能够分别与溶菌酶的某些反应位点反应生成特征性的反应产物,有利于这些炸药的分析与检测.  相似文献   
5.
运用分子动力学(MD)方法,选择凝聚态分子势能优化力场(COMPASS),对六硝基六氮杂异伍兹烷(ε-CL-20)、2,4,6-三硝基甲苯(TNT)晶体及其等摩尔比的CL-20/TNT混合炸药和共晶炸药进行不同温度下恒定粒子数等压等温(NPT)系综模拟研究.结果表明,CL-20/TNT共晶的内聚能密度(CED)和结合能随温度的升高逐渐减小;共晶的CED比混合炸药的大,结合能是混合炸药的2倍多,预示其稳定性明显增强.对相关函数和局部放大结构显示共晶中组分分子间作用主要来自TNT中H和CL-20中O以及CL-20中H和TNT中O之间形成的氢键.通过波动法求得的弹性力学性能结果表明,CL-20/TNT共晶的拉伸模量(E)、体积模量(K)和剪切模量(G)介于ε-CL-20和TNT晶体之间,且随温度的升高而下降,符合一般预期;但共晶炸药的柯西压(C12-C44,Cij弹性系数)、K/G和泊松比(ν)均比其组分炸药ε-CL-20和TNT高得多,预示该共晶具有异常高的延展性和弹性伸长,主要是二组分呈层状交替排列且之间存在较强相互作用所致.  相似文献   
6.
    
Aqueous microdroplets strongly attach to metallic needles with superhydrophobic sides and flat hydrophilic tips. Such needles can be made surface-enhanced Raman spectroscopy (SERS)-active by adsorbing a layer of densely packed and uniform plasmonic nanoparticles onto the hydrophilic tip. The resulting particle-tipped needles allow dual enhancement of the Raman signals from microdroplets of low concentration analytes by combining analyte enrichment through solvent evaporation and plasmonic SERS enhancement. The combination of small sample volume, preconcentration, and SERS allows extremely low total amounts of analytes to be detected. Here, we show that with crystal violet as the model analyte, the limit of detection can reach 2 pg. The method can be readily used to fabricate superhydrophobic needles tipped with different types of plasmonic colloidal nanoparticles for enhanced Raman analysis, for example, silver cube tipped needles could be used to detect as little as 2.5 ng of trinitrotoluene.  相似文献   
7.
    
Within the framework of finite element systems, we show how spaces of differential forms may be constructed, in such a way that they are equipped with commuting interpolators and contain prescribed functions, and are minimal under these constraints. We show how various known mixed finite element spaces fulfill such a design principle, including trimmed polynomial differential forms, serendipity elements and TNT elements. We also comment on virtual element methods and provide a dimension formula for minimal compatible finite element systems containing polynomials of a given degree on hypercubes. https://doi.org/10.1051/m2an/2015089  相似文献   
8.
研究气相色谱在测定废水、废酸中甲苯、硝基甲苯含量方面的应用.根据相关标准及废酸、废水处理的实际情况确定最佳的实验条件,废水样12次测定结果的相对标准偏差小于0.5%,加标回收率为98.31%.该法测定结果精确度高,适合DNT废酸、废水处理的分析监控.  相似文献   
9.
Large-pore-size (150 nm) polystyrene (PSt) microspheres were carboxylated with phthalic anhydride (PA) through Friedel-Crafts acetylation to study the adsorption of 2,4,6-trinitrotoluene (TNT) on this material from aqueous solution. The scanning electron microscope (SEM) images and mercury porosimetry measurements (MPM) of the microspheres showed that the pore structure was unchanged during the reaction. High adsorption capacity (11.2 mg g−1 of suction-dried adsorbent) and adsorption rate (33.9 mg g−1 h−1) for TNT were observed during the study. As shown by the adsorption isotherm, the adsorption of TNT on PA-PSt can be described by the Freundlich adsorption equation, indicating heterogeneous adsorption process. On-column adsorption of TNT on PA-PSt and elution indicated that TNT can be completely removed from aqueous solution and condensed into acetone.  相似文献   
10.
用酶联免疫-化学发光法测定ANT的实验研究   总被引:1,自引:0,他引:1  
本文报道了酶联免疫-化学发光法测定ANT的实验研究.兔抗ANT抗血清滴度1/500~1/104,ANT检测范围0~10μg/ml.  相似文献   
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