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Liu D.-Y.,Nanjing University of Science and Technology | Zhao Z.-Y.,Xian North Huian Chemical Industries Co. | Yu Y.-G.,Nanjing University of Science and Technology | Lu X.,Nanjing University of Science and Technology | And 2 more authors.
Huozhayao Xuebao/Chinese Journal of Explosives and Propellants | Year: 2011

The surfaces of multiperforated propellant particles were coated with high molecular materials in different thickness. The deterrent coated propellants and traditional propellants were mixed and charged in a closed vessel and ignited to test the combustion retardation of deterrent coated propellants by recording the pressure-time profiles of combustion gases. A numerical model which included the heat and mass transfer between the combustion gases and coating layer to describe the combustion retardation of deterrent coated propellant was proposed. The combustion retardation of deterrent coated propellants was simulated. The results indicated that the combustion retardation time decreased with the increasing of pressure, and the adjustment of thickness and components of deterrent could augment the retardation time. The consistency of calculated pressure and time profiles with experimental ones indicated that the proposed model was effective for the simulation of combustion retardation of deterrent coated propellants.

Liu D.,Nanjing University of Science and Technology | Zhao Z.,Xian North Huian Chemical Industries Co. | Yu Y.,Nanjing University of Science and Technology | Zhou Y.,Nanjing University of Science and Technology | And 2 more authors.
Combustion Science and Technology | Year: 2012

The combustion characteristics of deterrent-coated propellants and their application in a 105mm caliber gun are investigated experimentally. The mixture of deterrent-coated and conventional single base propellant particles are fired in a 100ml closed bomb with loading densities of 0.1g/cm 3 and 0.2g/cm 3, respectively. The measured pressure time profiles indicate that the deterrent can retard the combustion of coated propellants, and the delays are related to the pressure and the thickness of the deterrent. The optimized deterrent-coated propellants are attached to the tailfin of a 105mm caliber armor piercing projectile (APP) as traveling charge, and fired in a 105mm caliber gun. The firing results indicate that the traveling charge of deterrent-coated propellants can improve the muzzle velocity of projectiles by 2.8% and 4.2% under maximum pressure of 330Mpa and 400Mpa, respectively. The pressure time curves measured in the chamber indicate that pressure plateau effects can be expected by the combustion delay of deterrent-coated propellants. © 2012 Copyright Taylor and Francis Group, LLC.

Qiu L.,Beijing Institute of Technology | Shao Z.,Beijing Institute of Technology | Wang J.,Beijing Institute of Technology | Zhang D.,Beijing Institute of Technology | Cao J.,Xian North Huian Chemical Industries Co.
Acta Chimica Sinica | Year: 2013

The study on electrospinning of natural polysaccharide polymer to be nano-crystallized is still difficult in the current time. Carboxymethyl cellulose sodium (CMC-Na) was successfully synthesized and acidized to obtain carboxymethyl cellulose hydrogen (CMC-H), and new ionic cellulose ether CMC-Li was synthesized by alkalization, and then we analyzed the difference of structure between the three products. By comparing the rheological measurement and analysis of CMC-Na and CMC-Li, which have different mass fractions, it is found that they both show the characteristics of non-Newtonian fluid. The non-Newtonian index of CMC-Li is lower than that of CMC-Na when the degree of substitution (DS) and viscosity of both is similar. For the same material, the ionic cellulose ether solution of lower DS and higher concentration shows the lower non-Newtonian index. For the structure and property characteristic of polymers, it was easy to combine them with water-soluble hydroxyl terminated high molecular weight polyethylene oxide (PEO) to allocate the excellent electrospinning solution. Processing conditions were adjusted to a flow rate of 4 mL/h, an applied voltage of 25 kV, the spinning distance of 12 cm, the better appearance of nanofibers whose average diameter is about 70 nm can be obtained. In the process of electrospinning, hydroxyl lithium ester enolates was obtained by reductive reaction of the ionized Li+ with active hydroxyl, which caused the molecular structure to be destroyed. CMC-Li showed the exceptional Non-Newtonian fluid properties and had the better spinning performance than CMC-Na. When the surface tension of liquid was damaged by external electric force of spinning voltage to balance each other, the obtained morphology of the fiber was better. Nano-aluminum powder is coated with CMC-Li to form composite nanofibers, and carbonized at the high temperatures. Al/CNF/Li composite fiber was obtained in which nano particles were uniformly distributed. We preliminarily studied the obtained composite material that remained morphology and structure of fiber, which lays the foundation for the later research that the material is applied to soluble membrane, tissue engineering scaffolds, biological medicine, lithium battery and super capacitor, etc. The satisfactory effects have been achieved through analysis of IR, Rheology and SEM. The paper expands the type of polysaccharide polymer that can be electrospun and filled the void of related research, and it also lays the foundation for the study on nano functional materials of new ionic cellulose ether. © 2013 Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences.

Zou W.-W.,Beijing Special Machinery Research | Hao X.-Q.,Beijing Special Machinery Research | Zhang Z.-Y.,Beijing Special Machinery Research | Dang H.-Y.,Xian North Huian Chemical Industries Co. | And 2 more authors.
Huozhayao Xuebao/Chinese Journal of Explosives and Propellants | Year: 2015

In order to improve the burning-off property, three small-bored combustible cartridge cases with energetic fibers were prepared by pulp molding method based on basic formulation. The pore structure, combustion performance, mechanical characteristics and ballistic property were analyzed by the instrusion porosimeters, the closed-bomb tests, the mechanical tests and the shooting tests. Results show that pores of combustible cartridge case are mainly slit-shaped and wedge-shaped, and pore size distribution is scattered. The porosity of combustible cartridge case is over 25%. The pore volume of combustible cartridge case is above 0.25 cm3/g, and the specific surface area is about 20 m2/g. Cigarette sensitivity of combustible cartridge case with heat-resistant coating is above 6s at 400℃. The small-bored combustible cartridge case with the energetic fibers is beneficial to increase the porosity and the burning rate, shorten the constant volume combustion time and improve the burn-off properties. In shooting tests of charge, the ballistic property of the mixed charge of combustible cartridge case can be improved by adding energetic fibers. ©, 2015, China Ordnance Industry Corporation. All right reserved.

Li H.,Xian Modern Chemistry Research Institute | Wang B.-Z.,Xian Modern Chemistry Research Institute | Yu Q.-Q.,Xian North Huian Chemical Industries Co. | Li Y.-N.,Xian Modern Chemistry Research Institute | Shang Y.,Xian Modern Chemistry Research Institute
Hanneng Cailiao/Chinese Journal of Energetic Materials | Year: 2012

3, 3'-Bis(tetrazol-5-yl)difurazanyl ether was designed and synthesized with a yield of 46.7% from 3-amino-4-cyano furazan through oxidation, ertherification and cyclization, and was characterized by 13C NMR, IR, MS and elemental analysis. In addition, the mechanism of cyclization promoted by Zn 2+ was proposed and discussed, and the reaction conditions of cyclization were optimized as follows: time is 4 h, ZnCl 2·2H 2O as catlyst, molar ratio of ZnCl 2·2H 2O to FOF-2 is 1:1.

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