龙格氮量计法测定火药中硝化棉含氮量

火药能量的大小与硝化棉含氮量的高低有着直接关系。硝化棉是火药中的主要能量来源之一。由于火药在贮存过程中的不断分解,使硝化棉含氮量逐渐减少,能量下降,机械强度降低和弹道性能变坏,用龙格氮量计法测定库存火药中硝化棉的含氮量具有重要意义。     

硝化工艺及原料的预处理对硝化棉含氮量及其分布均匀性的影响

采用硝化棉(NC)含氮量及其分布均匀性测试仪,考察了硝化系数、精制棉的膨润预处理和超声预处理三因素对硝化棉含氮量及氮量分布均匀性的影响规律.结果表明,NC的含氮量随硝化系数的增大而增大.当硝化系数分别为40、50和80时,NC含氮量分布值Dε较小,当硝化系数为20或100时,Dε值均显著增大;采用硫脲和尿素水溶液预处理...     

硝化棉含氮量对叠氮硝胺发射药力学性能的影响

利用我国现有的力学性能测试手段全面研究了硝化棉含氮量对叠氮硝胺发射药低温力学性能的影响。试验结果表明，在-40℃时，由含氮量为12．6％的硝化棉制得的发射药，其力学性能优于硝化棉氮量为13．0％的发射药。     

硝化棉氮含量的测定方法

对硝化棉含氮量测定方法及各自特点作了简述,并对硝化棉氮含量测定方法的前景进行了展望。     

近红外漫反射光谱法测定硝化棉含氮量的数值模拟及实验研究

通过对107个硝化棉样品的近红外漫反射光谱及其含氮量参比值的研究,采用偏最小二乘法建立了测定硝化棉含氮量的数学模型。用t-对子检验对比了其与化学分析法的结果。结果表明,该模型的交互验证决定系数(R2)为0.998 1,交互验证残差均方根(RMSECV)为0.026%;外部验证的残差均方根(RMSEP)为0.023%。t-对子检验表明,近红外光谱法与化学分析法无显著差异。该方法将分析时间缩短到3min以内,可代替化学分析方法。     

硝化体系及精制棉干燥处理对硝化棉含氮量均匀性的影响

将不同预处理方法得到的精制棉在普通硝硫混酸体系和绿色无硫硝化体系(HNO3/CH2Cl2)中进行硝化,采用偏光显微镜研究了产物硝化的均匀性。结果表明,改变原料棉纤维素处理方法,产物硝化的均匀性有较明显的变化,对原料棉纤维素进行干燥处理后,硝化产物性能有较明显的变化,适当含有水分的棉纤维素干燥处理后,由于角质化作用,制得的硝化棉(NC)含氮量和硝化均匀性比干燥处理前均有所降低;含氮量不同,产品的硝化均匀性有规律性变化,在中含氮量(如12%)时,NC的均匀性比含氮量为13%或11%的硝化棉好。     

单基发射药硝化棉含氮量测定方法的改进

单基发射药中硝化棉含氮量的测定方法,目前国内一般采用量气法、亚铁还原法、干涉仪法以及狄瓦尔德合金还原法.上述四种方法都需要一套较复杂的仪器设备和相应的操作技术,一般工人难于掌握.笔者在没有蒸气发生器的设备条件下,以狄瓦尔德合金还原法为基础,初步摸索出单基发射药硝化棉中含氮量的简易测定方法,结果比较满意.     

民用硝化棉生产中含氮量的控制

阐述了硝化棉关键质量指标含氮量的影响因素,对有效控制其含氮量的工艺技术进行了较深入地探讨与研究,确定了相应的工艺参数与条件。     

HYCAR组成对它与NC相容性的影响

利用静态溶剂吸附法测试含氮量为 12 .5 %的硝化棉和丙烯腈基团含量不同的丁腈橡胶的各种混合体系 Gibbs自由能。分析结果表明 :随着橡胶中丙烯腈比例增大 ,这两种高聚物共容区逐渐扩大 ,当橡胶中丙烯腈基团含量达到 40 %时二者完全相容。     

含硝胺和铝粉的少烟改性双基推进剂表面和界面性能

研究了不同含氮量的硝化棉(NC)和不同粒度填料(Al、RDX和HMX)的表面性能,NC与填料之间的界面性能,以及表面和界面性能对含硝胺和铝粉的少烟改性双基推进剂力学性能的影响.结果表明,随着RDX、HMX以及A1粉粒度的减小,其表面张力逐渐增大,RDX、HMX与NC之间的界面张力随着RDX和HMX粒度或硝化棉含氮量的减...     

The birefringence of nitrocellulose fibers and pastes

The optical path difference of nitrocellulose fibers and pastes were measured on the polarizing microscope using three different compensation techniques, and a method is suggested for converting these path differences into birefringencies. By taking measurements on a sufficiently large number of fibers it is possible to estimate the average nitrogen content with an accuracy approaching that achieved by other methods on much larger samples. The distribution of nitrogen between individual fibers shows that material prepared by the displacement process differs from that made by the mechanical process and indicates that denitration occurs during displacement process manufacture. Solvents and plasticizers either increase or decrease the birefringence, and the structure of nitrocellulose pastes is discussed.     

利用全自动定氮仪测定硝化棉的含氮量

采用自行研制的全自动定氮仪测定硝化棉的含氮量,研究了样品前处理条件、全自动定氮仪实验参数对检测结果的影响;讨论了实验的准确性与重复性,对全自动定氮仪法与传统合金还原法进行了比较。结果表明,样品前处理采用石墨炉加热,梯度升温的皂化模式;最佳实验参数为:蒸汽体积分数80%、预热30s、还原反应7min、硼酸体积35mL、蒸馏时间8min;与传统合金还原法相比,采用全自动定氮仪检测硝化棉含氮量的方法用时少、操作简单,自动化程度高,减少了人为误差的影响,可保证结果的精度和准确性。     

Temperature effects on the birefringence of nitrocellulose and nitrocellulose/nitroglycerine mixtures

Changes in the optical path difference of nitrocellulose fibres of varying degrees of substitution over the temperature range ?120°C to 130°C are interpreted as due to conformational changes in the primary nitrate group. Changes in path difference of nitrocellulose/nitroglycerine paste fibres over the same temperature range indicate an irreversible annealing effect and a change in the nitrocellulose structure. Propellants made from nitrocellulose and nitroglycerine show similar changes and it is concluded that submicroscopic fibrils are present even though no fibres are visible. When fibres are visible they show a banded structure, the nature of which is discussed.     

微米级硝化纤维素的制备及性能研究

为了使硝化反应在近似均相的条件下进行,采用对精制棉进行水解处理,用稀酸水解法制得结晶度较为一致的微晶纤维素,再用硝硫混酸进行硝化得到微米级硝化纤维素。用扫描电镜和红外光谱对其微观形貌和结构进行了表征。用DSC分析了其热性能,并测试了其撞击感度和黏度。结果表明,制备微米级硝化纤维素的最佳条件为:硝硫混酸体积比为1∶3,硝化时间30min,硝化温度为35℃。制得的微米级硝化纤维素样品粒度均匀,其特性落高为57.466cm,黏度为478mPa·s,分解峰温达到211.20℃,硝化均匀,含氮量可达12.8%。     

Microscopic determination of degree of nitration of nitrocellulose with dispersion staining

A microscopical method with dispersion staining has been developed for determining the degree of nitration of nitrocellulose (NC). In the method the per cent nitrogen in unknown samples is obtained by matching the colors of dispersed refracted light between an oil of known refractive index and films of the unknown and an NC standard. Agreement with standard Du Pont Nitrometer results were excellent. Color differences were detected as the nitrogen content of the NC ranged between 12.55 and 13.5% with central screening and the polarizer. The sensitivity was found to be increased by crossing the analyzer with the polarizer and observing the phase differences resolved in the analyzer.     

Sorption of nitroglycerine from solution by granular nitrocellulose

Two nitrocelluloses of 12.7 and 14.0% nitrogen contents were prepared and fractionated to give samples having M?_n values in the range 2,200—388,000. The effect of chain-length of the nitrocellulose samples, having the same nitrogen content, on the sorption of nitroglycerine from n-hexane solution was investigated by means of partition equilibrium experiments. The separate effect of nitrogen content on sorption of nitroglycerine was determined by comparison of sorption isotherms for samples of similar molecular weight but different nitrogen contents. The amount of nitroglycerine taken up was greater for the lower nitrogen content samples, but sorption was not influenced by the molecular weight of the nitrocellulose. The results are discussed in terms of the molecular structure of the nitrocellulose samples, which is determined by the orientation and spacing of the chains in the crystalline and amorphous regions.     

利用新型硝化体系制备硝化纤维素的工艺研究

研究了N2O5-N2O4-HNO3新型硝化体系对纤维素硝化反应中各组分和反应条件对硝化纤维素含氮量及其质量的影响,探讨了硝化组分及反应条件影响硝化纤维素含氮量和分布的规律和内在原因,达到通过调节硝化剂组分含量和反应条件的变化控制硝化纤维素含氮量的目的。