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1.
纳米LLM-105自组装制备矩形微米棒   总被引:1,自引:1,他引:0  
以纳米级2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)为原料,采用溶剂诱导自组装法制备了横截面为矩形的LLM-105微米棒,并将制备的矩形LLM-105微米棒与直接合成的孪晶LLM-105样品进行了对比分析。研究了溶剂、纳米级LLM-105加入量、搅拌速率和自组装时间对自组装后LLM-105晶体形貌的影响,得到了最优自组装条件,发现以二甲基亚砜(DMSO)为溶剂,纳米LLM-105的加入量为40 g·L~(-1),搅拌速率为600 r·min~(-1)时以纳米LLM-105为原料自组装可得到规则的矩形棒状晶体,并提出了其可能的生长机理。采用扫描电子显微镜,X射线粉末衍射,差示扫描量热-热重,高效液相色谱分别对自组装后晶体的形貌、结构、热性能以及纯度进行了表征,发现自组装矩形LLM-105微米棒与直接合成的孪晶LLM-105相比,XRD主要衍射峰完全一致,但在2θ为11.1°、22.3°、24.8°和33.0°处的衍射峰强度有所降低,晶体可能沿着(100)方向择优生长;晶体纯度提高了1.8%,达到为98.8%;自组装制备得到的微米LLM-105晶体具有更好的热稳定性,仅存在356.7℃一个放热峰,热失重起始温度提高了34.8℃。  相似文献   

2.
周小清  单军辉  陈东  郝世龙  李洪珍 《含能材料》2021,29(12):1168-1175
为了研究晶体形态对炸药物化性能、应用方式和应用效果的影响,采用溶剂-非溶剂结晶法,分别以二甲亚砜(DMSO)为溶剂、乙酸乙酯为非溶剂、1-乙基-3-甲基咪唑乙酸盐(EmimOAc)为结晶助剂,制备得到花球状2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)晶体.EmimOAc的添加显著增强了LLM-105在DMSO中的溶解度,改变了LLM-105晶体生长方式和结构形态,对晶型无影响.热分析测试结果表明:花球状LLM-105晶体有两个明显的分解峰温,分别为347.3~350.5℃和356.7~360.4℃.采用GJB-772A-1997方法601.2测试了花球状LLM-105晶体的撞击感度,采用冲击片雷管起爆测试方法测试了花球状LLM-105晶体的冲击片起爆感度,结果表明:花球状LLM-105晶体的撞击感度与亚微米晶体相当,显著低于针状晶体;冲击片起爆电压低于亚微米晶体.  相似文献   

3.
徐容  廖龙渝  王述存  张勇 《兵工学报》2015,36(11):2099-2103
2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)是性能优异的耐热炸药,其晶体形状对安全及加工性能有较大影响,重结晶溶剂和方法直接影响所得LLM-105的晶体特性。用二甲基亚砜和65%硝酸为溶剂,分别采用降温法、正相和反相溶剂/非溶剂法及超声波辅助结晶的方法,对LLM-105进行了重结晶研究。研究结果表明:无论用何种溶剂,直接降温法重结晶得到的LLM-105,晶体形状均不规则;用溶剂/非溶剂正相滴加法在超声作用下可以得到表面光滑、无孪晶的颗粒状晶体,纯度达98%以上;用溶剂/非溶剂反相滴加法也可以得到表面光滑、无孪晶的规则颗粒状晶体,纯度达98%以上;用65%浓度的HNO3水溶液反相滴加重结晶得到的LLM-105晶体平均粒径适中,粒度跨度小,撞击感度最低。获得了纯度和晶型好,感度大幅度降低LLM-105的制备方法:65%HNO3水溶液反相滴加法。  相似文献   

4.
为了研究2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)的结晶成核过程,利用CrystlScan多通道结晶仪测量了不同过饱和度比下LLM-105反溶剂结晶成核诱导期。采用诱导期测量法研究了过饱和度对LLM-105成核的影响并结合经典成核理论计算了成核的重要参数。结果表明,LLM-105反溶剂结晶的诱导期随过饱和度的增大而降低。当过饱和度比S2.53时,主要发生异相成核,界面张力γ值为6.67717×10~(-23)J·m~(-2),表面熵因子f值为1.49;当S2.53时,主要发生均相成核,界面张力γ值9.98942×10~(-23)J·m~(-2)表面熵因子f值为2.23。表面熵因子值均小于3,表明LLM-105在乙酸乙酯为反溶剂结晶中的生长方式为连续生长机制。另外,当LLM-105反溶剂结晶为发生均相成核时,成核速率随着过饱和比的增加而增加,临界晶核半径和临界成核数量均随着过饱和比的增加而减小。  相似文献   

5.
LLM-105重结晶与性能研究   总被引:11,自引:7,他引:4  
研究了LLM-105的重结晶方法。结果表明,不同重结晶方法获得的LLM-105平均粒径、纯度和撞击感度差别较大,其中冷却法和溶剂(DMSO)-非溶剂(热水)法结晶产品撞击感度较低,H50值分别为120.0cm和108.3cm。采用DSC?TG、VST、TG和热爆炸等方法研究了LLM-105的热性能,DSC放热起始温度为341.2℃(升温速率10℃.min-1),120℃条件下48h放气量为0.016mL.g-1,120℃条件下48h热失重为0.13%,5s延滞期爆发点为367.6℃;VST测试结果表明,LLM-105与HMX、AS、F2311、F2314、Estane的相容性良好。测定LLM-105爆速(LLM-105/F2314=95/5,1.845g.cm-3,96.4%TMD)为7991m.s-1。压力-密度测试结果表明,LLM-105具有良好的压缩成型性能。  相似文献   

6.
为改善2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)的形貌以及减小粒径。基于溶剂-非溶剂法,通过超声辅助微流控技术制备纳米LLM-105。采用场发射扫描电镜(FE-SEM)观察样品的微观形貌,X射线衍射(XRD)分析样品的晶型。此外,通过流体可视化证明了超声波对于流体混合的促进作用。结果表明,通过超声所制备的样品颗粒更小,粒径更均匀,平均粒径为137.65 nm,并且形貌为类球型,且晶型较原料未发生改变。差示扫描量热分析(DSC)表明纳米LLM-105的热分解温度较原料降低。说明超声辅助的引入,不仅可以提高制备纳米LLM-105的效率,还会使其粒径显著减小。  相似文献   

7.
为改善2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)的晶体形貌,控制LLM-105的晶体粒度,利用CrystalSCAN多通道结晶仪,采用浊度法测定了LLM-105在二甲基亚砜(DMSO)中的介稳区宽度。研究了初始浓度、搅拌速率和降温速率对介稳区宽度的影响。根据经典成核理论,计算了受降温速率影响的成核级数。结果表明,在降温结晶过程中,LLM-105在DMSO中的介稳区宽度随初始浓度,搅拌速度的增加而变窄,随着降温速率的增加而变宽。得到的最佳结晶条件为:初始浓度0.0700 g·mL~(-1),搅拌速率390 r·min~(-1),降温速率1.0℃·min~(-1)。当初始浓度从0.0670 g·mL~(-1)增至0.0750 g·mL~(-1)时成核级数从1.825升高到2.5747。在最佳结晶条件下,添加2.5 g粒度为4μm的LLM-105晶种于DMSO-LLM-105溶液中,可获得表面光滑、形貌规则、粒度(60μm)可控的高品质LLM-105柱状颗粒。  相似文献   

8.
高聚物与2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)的界面相互作用直接影响LLM-105的表面包覆效果,在原子分子层次的作用模式和强度分析,有助于揭示界面相互作用的微观机制。采用分子动力学(MD)方法,模拟了氟聚物(F_(2311),F_(2313),F_(2314),F_(2462))和聚氨酯(Estane 5703)与LLM-105不同晶面的界面相互作用,分析了高聚物与LLM-105晶面的作用模式和强度,初步提出了高聚物黏结剂的筛选原则,并采用该原则筛选了一个新的高聚物——硝化细菌纤维素(NBC),同时模拟了其与LLM-105晶面的相互作用。采用静态弹性常数分析法讨论了6种高聚物对LLM-105力学性能的影响。模拟结果表明,所选高聚物与LLM-105各晶面的结合能均为正值,结合强度从大到小的顺序为LLM-105/NBC≈LLM-105/Estane 5703LLM-105/F_(2313)≈LLM-105/F_(2314)≈LLM-105/F_(2311) LLM-105/F_(2462)。结合能最大的(1 0 1)晶面,在晶体中的显露面最小(0.39%),而结合能小的(0 2 0)和(0 1 1)晶面,其显露面却占了很大比例(二者之和60%)。在界面相互作用中,范德华力均占据优势地位,远远超过静电相互作用。能与LLM-105发生强相互作用的高聚物应能同时提供氢键良给体和良受体。通过对有效各向同性模量和柯西(Cauchy)压值的分析得到,加入NBC、Estane 5703和F_(2462)对LLM-105力学性能有所改善,F_(2311)和F_(2313)未有改善,而F_(2314)则有所下降。  相似文献   

9.
制备了1-磺酸丙基-3-甲基咪唑硫酸氢盐[MIMPS][HSO4]离子液体,以[MIMPS][HSO4]作为催化剂,应用于N2O5/有机溶剂硝化2,6-二乙酰氨基吡嗪-1-氧化物合成2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105).通过1 H NMR,IR和MS对LLM-105及其中间体的结构进行了表征.研究了在[MIMPS][HSO4]催化条件下,反应溶剂、催化剂用量、反应温度和反应时间对LLM-105收率的影响,结果表明最佳反应条件为:采用CH3NO2为反应溶剂,反应温度为55 ℃,反应时间为6h,LLM-105的收率为72.2%.研究了[MIMPS][HSO4]的循环使用性能.结果表明,平行实验5次,平均收率71.7%,具有较好的可再生利用性.  相似文献   

10.
LLM-105炸药制备工艺改进   总被引:5,自引:4,他引:1  
为了降低1-氧-2,6-二氨基-3,5-二硝基吡嗪(LLM-105)的制造成本,以2,6-二氨基-3,5-二硝基吡嗪(ANPZ)为原料,高浓度双氧水为氧化剂,合成了LLM-105。探讨了50%和85%浓度双氧水对LLM-105氧化反应的影响。三氟乙酸用量较原方法减少50%。用正交实验优化了LLM-105氧化合成工艺。确定的最佳工艺条件为:n(ANPZ)n( 50%H2O2)=16,m(ANPZ)V(TFA)=15(gmL),反应温度25~30 ℃,反应时间24 h。LLM-105的收率为95%,纯度为98%。用红外光谱、核磁共振光谱、元素分析、质谱表征了其结构。   相似文献   

11.
Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.  相似文献   

12.
The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.  相似文献   

13.
Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.  相似文献   

14.
By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.  相似文献   

15.
By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.  相似文献   

16.
The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.  相似文献   

17.
Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.  相似文献   

18.
The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent "explosion of terms". Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.  相似文献   

19.
An expression for estimating the aeroheating on a warhead nose at different supersonic speeds is proposed by incorporating CFD (computational fluid dynamics) and the least-square method. Compared with the traditional estimation formula, the expression is more accurate, convenient and can be used in the optimized design of warheads. The error from the result obtained in the test of a ball cartridge flight is less than 3 %. It satisfies the engineering requirements.  相似文献   

20.
A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.  相似文献   

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