炸药爆炸残留物分析研究进展

爆炸案件严重危害国家安全及社会稳定,给人民生命财产安全带来巨大威胁。在爆炸案件中,爆炸残留物分析是爆炸原因调查和案件侦破的重要环节,可为侦查提供方向和线索,也可为证实犯罪事实、法庭诉讼和定罪量刑提供关键证据。本文综述了国内外爆炸残留物分析领域光谱、色谱、质谱等技术的研究进展,针对我国非法制造、销售、储存和使用自制炸药的爆炸案件多发的现状,展望了我国法庭科学领域爆炸残留物分析的发展趋势,并总结出爆炸残留物实验室检验流程图,旨在为完善我国爆炸残留物检验技术体系、提高我国刑事技术部门爆炸残留物检验水平提供借鉴和参考。     

强磁场碳黑催化法制备纳米新金刚石粉

在直流恒稳强磁场(10T)作用下,以纳米铁为催化剂,碳黑为碳源,在常压和1100℃下保温100min成功地制备出了类金刚石和新金刚石,并用XRD,TEM和Raman对制备的样品粉末进行表征．结果表明,样品粉末是由纳米类金刚石粉和石墨包覆新金刚石纳米颗粒组成,纳米类金刚石粉的大小为20nm,石墨包覆新金刚石的大小为100nm．     

纳米金刚石球晶的激光溅射产生

以脉冲激光束溅射浸入水中的单质碳样品.观察到产生一种外形完美且具有金刚石结构的纳米碳球.研究中考察了处于固/液界面的各种碳源在脉冲激光作用下发生的变化,初步探讨纳米碳球的形成原因.研究结果揭示:对于表面悬挂键为其他基团所饱和的纳米碳粒,金刚石与石墨结构的热力学稳定性相近,并且当熔融碳的尺寸小至纳米级时,其表面张力能产生较高的压力,因此使它同样有可能凝聚成金刚石的结构.     

纳米金刚石球晶的激光溅射产生与透射电镜表征

在高温高压合成金刚石技术日趋成熟的同时，气相沉积（CVD）条件下实现常压金刚石膜的合成已倍受人们的关注．利用脉冲激光溅射石墨，发现可在一定的基底上获得一类具有某些金刚石特征的薄膜，即类金刚石碳膜（DLC）［‘－‘j．这为在常规条件下合成金刚石带来了新的希望．但DLC只具有金刚石的某些特征，而基本上不具备晶体的有序结构［”’j．我们曾报道了在激光液相溅射的产物中观察到众多的碳球D‘，并通过高分辨透射电镜（HREM）、选区衍射（SAED）及其它相关实验，确定了其具有金刚石结构．且实验部分实验所用的激光是Q开关Nd…     

无机炸药爆炸残留物检测方法的研究进展

对常用的无机炸药爆炸残留物检测方法:离子色谱法、拉曼光谱法、毛细管电泳法、扫描电镜能谱法等方法进行了综述,分析了各种检测方法的应用特点,并针对当前法庭科学领域的应用需求,提出了无机炸药爆炸残留物检测方法的主要研究方向,旨在为无机炸药爆炸残留物的研究和侦查办案提供参考.     

毫秒脉冲激光合成超细纳米金刚石

通过热力学和动力学的基本理论, 分析了毫秒脉冲激光照射石墨悬浮液合成超细纳米金刚石的机理. 在毫秒脉冲激光与石墨颗粒相互作用形成的碳蒸气羽中, 通过碳蒸气凝聚形成了金刚石核. 与纳秒脉冲激光相比, 毫秒脉冲激光具有较低的功率密度和较长的脉宽, 为金刚石核的生长提供了较小的过冷度, 使得金刚石核的生长速率减小; 而较小的生长速率也为金刚石表面形成sp2杂化结构提供了机会, 它可以有效降低金刚石核的表面能, 促使金刚石核稳定, 但表面的sp2杂化也阻止了金刚石核的外延. 以上两个原因决定了毫秒激光辐照石墨颗粒过程中只能获得超细的纳米金刚石.     

炸药爆轰合成纳米石墨的红外光谱研究

石墨是碳材料中最常见的结晶状态,它具有耐高温、抗腐蚀、自润滑、无毒及价格低廉等特点,广泛应用于润滑剂和添加剂等方面^[1].由于高纯纳米石墨粉在某些高新技术领域中有较好的应用前景,近些年来得到开发和应用,如制成复合导电材料、吸波材料及储氢材料等^[2].以前有学者用纳米金刚石粉加热相转变^[3]和高能球磨^[4,5]的方法制备了纳米石墨,在制备碳纳米管时也有石墨的纳米粒子生成^[6].但用这几种方法制备纳米石墨,既费时又消耗较大能量,成本非常高.     

离子色谱法检验液体炸药爆炸尘土中的肼离子

建立了离子色谱检测液体炸药爆炸尘土中肼离子的方法。用去离子水超声提取尘土样品中的肼离子,离心后取上清液并将其分别过OnGuardⅡ RP小柱和0.22 μm过滤膜,经IonPac CS-12A阴离子色谱柱(250 mm×4 mm)分离,采用5 mmol/L甲基磺酸等度淋洗,0.1 mol/L NaOH溶液柱后加碱,金电极安培检测器检测。结果表明,肼离子质量浓度在0.02~2.0 mg/L范围内的线性关系良好(相关系数r²=0.9997)。以信噪比(S/N)为3确定方法检出限为5.0 μg/L, S/N为10确定方法定量限为16.6 μg/L。方法回收率在95.4%~99.1%之间,相对标准偏差(RSD, n=5)在2.1%~3.3%之间。应用该方法检测液体炸药爆炸尘土中肼离子的含量为10.3 mg/kg。该方法操作简便,结果准确,适用于液体炸药爆炸尘土中肼离子的定量检测,满足刑事物证鉴定工作的需要。     

纳米金刚石的表面修饰及应用

纳米金刚石是一种新型的碳纳米粒子,具有硬度高、化学稳定、良好的生物相容性和热传导性等优点,有广阔的应用前景。对于纳米金刚石的应用,大多需要对其进行表面修饰。本文主要结合近年来国内外研究成果,阐述了氢化、羧酸化、羟基化及其他表面修饰等纳米金刚石的表面修饰方法,总结了纳米金刚石在润滑、抛光、生物医学、复合材料等领域的应用。     

离子色谱和热解吸-气相色谱-质谱法测定炸药爆炸产物

用离子色谱和热解吸-气相色谱-质谱法测定炸药的爆炸产物.爆炸产物中的氰化物用0.1 mol·L-1氢氧化钠溶液吸收后,用离子色谱法检测,检出限(3S/N)为0.01 ug·L-1,回收率为92.6%,相关系数为0.999 8,测定结果的相对标准偏差为3.8%.爆炸产物的主成分和微量成分直接进样,用热解吸-气相色谱-质谱联用法分析,检测了联苯、1-甲基-(1H)-吡喏2-乙腈、5-氨基-3,4-二氢-(2H)-吡喏-2-乙腈、硝基苯、苯等有毒产物.     

爆轰法制备球形纳米CeO2粉末

采用爆轰合成的方法,以Ce(NO3)3·6H2O为原料,制得了CeO2纳米粒子. 炸药采用黑索金粉,添加剂为CO(NH2)2,NaNO2. 爆轰产物经水洗,烘干后,利用X射线衍射仪器和高分辨率透射电镜对实验结果进行了分析. XRD结果表明,该法所得到的CeO2为立方晶系,颗粒平均粒度为33 nm. TEM图像显示其颗粒呈球形,颗粒大小主要分布在20～40 nm之间,颗粒具有较好的分散性. 球形纳米CeO2颗粒的形成原因有两点:(1) 由于爆轰过程的快速性和急剧冷却的特点,CeO2晶粒来不及择优生长; (2) 产物Na2CO3的熔点较低,爆轰时呈熔融状态包覆在CeO2晶核的周围,阻隔了CeO2晶粒的团聚生长.     

六硝基六氮杂三环十二烷二酮的密度泛函理论研究

对迄今为止爆速最高的高能化合物六硝基六氮杂三环十二烷二酮(HHTDD)的结构和性质实现了DFT-B3LYP/CEP-31G水平的计算研究。其全优化几何构型中六员氮杂环可取椅式和船式2种构象,并以船式构象更稳定。基于集居数、自然键轨道(NBO)、分子总能量和前线轨道能量等电子结构参数对该化合物若干性质进行了探讨。尤其揭示了分子中NNO2键所表现出的最大活性。在振动分析的基础上求得273～800 K温度范围内体系的热力学性质。从理论上预测的爆速与实测值相吻合。     

A Simple Correlation for Assessment of the Shock Wave Energy in Underwater Detonation

Assessment of underwater detonation (explosion) is important for industrial purposes such as blasting cut of old warship, blasting droll and decoupled charge of blast underwater. Calculation of the shock wave energy requires several expensive experimental data such as the shock wave pressure and the representative time of the process. This work introduces a simple method for reliable prediction of the shock wave energy of composite explosives containing aluminum (Al) and/or ammonium perchlorate (AP), which show non‐ideal behavior. This method is based on the composition, loading density and the ratio of R/m^1/3, where R is the distance between the pressure gauge and charge as well as m is the mass of explosive charge. The measured data for 86 and 21 composite Al/AP explosives are used to construct and test the new model. Statistical parameters including the root mean squared error (RMSE), and maximum of errors (Max Error) of the new model are 0.11 and 0.39 MJ · kg^–1, respectively, which confirm high reliability of the new method. The values of RMSE and Max Error for test set are 0.13 and 0.30 MJ · kg^–1, respectively. Cross validation of the novel model is also used to evaluate its goodness‐of‐fit, goodness‐of‐prediction, accuracy and precision. It is shown that the novel correlation can be applied for pure and composite explosives without Al/AP.     

TATB/氟聚物PBX力学性能、结合能和爆炸性能的模拟计算

Molecular dynamics （MD） method was used to simulate 1,3,5-triamino-2,4,6-trinitrobenzene （TATB） coated with fluorine containing polymers. The mechanical properties and binding energies of PBXs were obtained. It was found that when the number of chain monomers of fluorine containing polymers was the same, the elasticity of TATB/F2314 was increased more greatly than others and the binding energy of TATB/F2311 was the largest among four PBXs. Detonation heat and velocity of such four PBXs were calculated according to theoretical and empirical formulas. The results show that the order of detonation heat is TATB〉TATB/PVDF〉TATB/F2311〉TATB/ F2314 〉 TATB/PCTFE while the order of detonation velocity is TATB/PVDF 〈 TATB/F2311 〈 TATB/F2314 〈 TATB/PCTFE 〈TATB.     

Characterization of Fine Hydroxyapatite Powders Synthesized by Wet Process

Abstract

We prepared fine hydroxyapatite powders by dropping ammonium bi-phosphate into a calcium acetate solution and by vigorously stirring at 3O°C. We measured the powders' specific surface area to be 290 m²/g by the BET technique. The powders were mono-dispersed ultrafine particles by transmission electron microscopy investigation. No phase other than hydroxyapatite (JCPDS: 9–432) was revealed by X-ray diffractometry. A quantitative chemical analysis gave a Ca/P ratio very close to the exact hydroxyapatite stoichiometry (Ca/P: 1.67). Shrinkage started up to 800°C according to a dilatometric measurement and the dense products were obtained when heated at 1000°C for 2 h in air. We used a quadrupole mass spectrometer to monitor the gases desorbed from the hydroxyapatite powders at a constant heating rate of 5°C/min in a high vacuum. It is noted here that there were two peaks of H₂O and CO₂, respectively, and that we observed an increase in desorption of H₂. The two peaks were explained clearly with an infrared spectrometry analysis and a thermal analysis we made separately.     

气相法合成一维无机纳米材料的研究进展

一维无机纳米材料是研究电子传输行为、光学特性和力学机械性能等物性的尺寸和维度效应的理想系统，将在构筑纳米电子和光电子器件等集成线路和功能性元件的进程中充当非常重要的角色，已成为当前纳米材料科学领域的前沿和热点。本文将从一维无机纳米材料的合成、表征和物性研究等方面，结合近年来国内外的最新进展对这一新兴领域作一概述。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.