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1.
HNIW在乙酸乙酯-正庚烷溶剂体系中的结晶机制研究   总被引:1,自引:0,他引:1  
六硝基六氮杂异伍兹烷(HNIW,CL-20)具有α-、β-、γ-、ε-等多种晶型,常压下,在不同溶剂系统中,晶型之间会相互转化.采用溶剂/反溶剂法,研究了正庚烷以不同速度加入到HNIW的乙酸乙酯饱和溶液中HNIW的结晶过程,采用红外光谱仪和扫描电子显微镜研究了结晶过程中HNIW的晶型和形貌.结果显示:当正庚烷的加料速度大于100 mL·s-1时,HNIW的结晶机理主要受动力学控制,先是亚稳相β-HNIW晶核的形成和生长,随后由亚稳相β-HNIW向稳定相ε-HNIW转变,最终全部变为ε-HNIW.当正庚烷的加料速度小于20 mL·s-1时,HNIW的结晶机理主要受热力学控制,不存在相转移,只有ε-HNIW的成核和随后生长.在结晶过程中如有水存在,则会生成水合α-HNIW.因此,制备ε-HNIW的溶剂一般采用非极性或极性小的溶剂,而不用极性大的溶剂.  相似文献   

2.
HNIW在乙酸乙酯-正庚烷溶剂体系中的结晶机制研究   总被引:3,自引:3,他引:0  
六硝基六氮杂异伍兹烷(HNIW,CL-20)具有α-、β-、γ-、ε-等多种晶型,常压下,在不同溶剂系统中,晶型之间会相互转化。采用溶剂/反溶剂法,研究了正庚烷以不同速度加入到HNIW的乙酸乙酯饱和溶液中HNIW的结晶过程,采用红外光谱仪和扫描电子显微镜研究了结晶过程中HNIW的晶型和形貌。结果显示:当正庚烷的加料速度大于100 mL.s-1时,HNIW的结晶机理主要受动力学控制,先是亚稳相β-HNIW晶核的形成和生长,随后由亚稳相β-HNIW向稳定相ε-HNIW转变,最终全部变为ε-HNIW。当正庚烷的加料速度小于20 mL.s-1时,HNIW的结晶机理主要受热力学控制,不存在相转移,只有ε-HNIW的成核和随后生长。在结晶过程中如有水存在,则会生成水合α-HNIW。因此,制备ε-HNIW的溶剂一般采用非极性或极性小的溶剂,而不用极性大的溶剂。  相似文献   

3.
用傅立叶变换拉曼光谱定量分析HNIW的β-和ε-晶型混合物   总被引:1,自引:1,他引:0  
孟征  卫宏远 《含能材料》2011,19(3):339-342
研究了以傅立叶变换拉曼光谱定量分析ε-HNIW中β-晶体含量的方法.通过分析(α-,β-,γ-,ε-)六硝基六氮杂异伍兹烷(HNIW)的傅立叶变换拉曼光谱图,以300~270 cm-1区域的吸收峰为ε-HNIW晶型纯度检测的定量依据.配制一系列不同配比的(β-,ε-)HNIW混合物,经拉曼光谱分析后绘制工作曲线,在28...  相似文献   

4.
六硝基六氮杂异伍兹烷的制备工艺及性能研究   总被引:3,自引:0,他引:3       下载免费PDF全文
研究了以四乙酰基二甲酰基六氮杂异伍兹烷(TADFIW)和四乙酰基二苄基六氮杂异伍兹烷(TADB IW)为硝解基质,经过硝解和转晶得到-εHNIW的热分解动力学参量和撞击感度,用电子扫描显微镜拍摄了ε-HNIW的晶体外貌。结果表明,两种-εHNIW的晶体外形相近,热分解动力学参量和撞击感度相同。这说明,两种-εHNIW样品的化学物理性质相同,虽然两种样品所含杂质不同,但对-εHNIW的热分解和撞击感度没有影响。  相似文献   

5.
六硝基六氮杂异伍兹烷转晶工艺最新研究进展   总被引:8,自引:6,他引:2       下载免费PDF全文
综述近五年六硝基六氮杂异伍兹烷(HNIW)转晶工艺的最新进展,包括多种经改进的实验室转晶方法及工业装置的转晶工艺。详细说明了转晶的操作程序及条件,提出了多种可供HNIW转晶采用的溶剂、非溶剂和晶型改性剂,讨论了结晶工艺对ε-HNIW结晶质量的影响。  相似文献   

6.
在82.48%~88.89%硝酸中,将四乙酰基二甲酰基六氮杂异伍兹烷(TADFIW)硝解为γ-六硝基六氮杂异伍兹烷(HNIW),得率88%以上,纯度99.4%以上。该方法最佳硝酸浓度为86.66%,此时HNIW得率94.0%,纯度99.51%。所得HNIW中所含的主要杂质为五硝基一乙酰基六氮杂异伍兹烷(PNMAIW),与TADFIW在硝硫混酸中硝解所得主要杂质五硝基一甲酰基六氮杂异伍兹烷(PNMFIW)不同,说明TADFIW在硝酸中硝解与在硝硫混酸中硝解的反应历程不同。  相似文献   

7.
四乙酰基二苄基六氮杂异伍兹烷(TADBIW)是制备六硝基六氮杂伍兹烷(HNIW)生产成本最低的硝解基质。本实验研究了由TADBIW制备HNIW时,HNIW晶型转变过程:硝解生成的是α-HNIW,后者在高温硝解系统中逐渐转变为.γ-HNIW,完成这种转变在70~75℃需3h,但晶体诱导体的加入能够加速这种转变。  相似文献   

8.
硝酸法制备六硝基六氮杂异伍兹烷   总被引:9,自引:1,他引:8  
本文研究使用浓度为90%~98%硝酸直接硝化四乙酰基六氮杂异伍兹烷(TAIW)制备六硝基六氮杂异伍兹烷(HNIW,CL-20)新方法,结果得到高产率高纯度的γ-HNIW.同时对反应中间产物二硝基,四硝基,五硝基衍生物进行了分离和鉴定,据此提出了分步硝化机理.  相似文献   

9.
晶形控制剂对ε-HNIW晶体形貌的影响   总被引:3,自引:2,他引:1  
孟征  卫宏远 《含能材料》2011,19(2):165-169
采用在乙酸乙酯-环己烷转晶体系中将y-型六硝基六氮杂异伍兹烷(γ-HNIW)转晶成ε-HNIW的方法,研究了晶形控制剂醇类化合物(A1)和羧酸类化合物(A2)对转晶产物ε-HNIW晶体形貌的影响.扫描电子显微镜(SEM)分析表明,晶形控制剂使ε-HNIW晶体的最终形貌发生改变,晶体表面更加光滑,表面缺陷减少.相对于不添...  相似文献   

10.
超细ε-HNIW的制备及表征   总被引:1,自引:0,他引:1  
利用微团化动态结晶法,以乙酸乙酯为溶剂、正庚烷为反溶剂,在不同的溶液浓度和温度条件下,制备了超细的六硝基六氮杂异伍兹烷(HNIW)。采用激光粒度分析仪、扫描电镜(SEM)和傅里叶红外光谱仪(FT-IR)对样品进行表征分析。结果表明:溶液浓度为0.4g/m L、温度为60℃时可得到中位径为450nm的超细HNIW混合晶体,粒度分布窄,呈近球形。所得混晶样品通过转晶实验,在乙酸乙酯/正庚烷混合溶液中搅拌6.5h,制得了平均粒度为1.36μm、粒度分布窄的超细ε型HNIW。  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.
The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.  相似文献   

19.
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   

20.
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   

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