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Prophylactic Effect of Gossypin Against Percutaneously Administered Sulfur Mustard

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Biomedical and Environmental Sciences 2007年第3期20卷 250-259页

作者： ANSHOO GAUTAM R.VIJAYARAGHAVAN Defence research and development establishment Gwalior-474002India

Objective To evaluate the protective efficacy of gossypin （3,3＇,4＇,5,7,8-hexahydroxyflavone 8-glucoside） by administering it intraperitoneally, for dose, time, and vehicle dependent effects against sulphur mustard （SM）, administered through percutaneous route in mice. Methods SM （diluted in PEG-300） was administered percutaneously. The protective efficacy of gossypin was evaluated by administering it intraperitoneally （50, 100, 200, and 400 mg/kg）, in various vehicles （water, PEG-300 and DMSO）, and time intervals （30 min prior, simultaneous and 2 h post）. The time dependent protection of gossypin （200 mg/kg in PEG-300; i.p.） was also evaluated using selected biochemical variables （GSH, GSSG, MDA, total antioxidant status, Hb, WBC count, RBC count, glutathione peroxidase, glutathione reductase, and superoxide dismutase） and liver histology. The protection of gossypin by oral route was also evaluated against percutaneously administered SM. Results The protection against systemic toxicity of SM （LD50 8.1 mg/kg） was better when gossypin was given with PEG-300 （8.0 folds） than DMSO （5.7 folds）. No protection was observed when gossypin was administered with water. Good protection （8.0 folds） was observed when gossypin was administered （200 mg/kg in PEG-300; i.p.） at 30 min prior or simultaneous to SM exposure, but no protection was observed when gossypin was administered 2 h post to SM exposure. A significant weight loss was observed 7 days after SM administration （2 LD50）, with a significant increase in RBC and Hb. A significant decrease in total antioxidant status of plasma, liver GSH and GSSG levels, and in the activities of glutathione peroxidase, glutathione reductase and superoxide dismutase was also observed 7 days after SM administration. SM treated mouse liver also showed necrosis. A significant protection was observed when gossypin （200 mg/kg in PEG-300; i.p.） was administered either as a pretreatment （30 min before） or simultaneous treatment, and not as a post

关键词： Sulfur mustard Gossypin Oxidative stress Glutathione Intraperitoneal Oral

Parametric study of single confined fragment launch explosive device

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Defence Technology（防务技术） 2019年第2期15卷 179-185页

作者： Pankaj K.Choudha A.Kumaraswamy Kusumkant D.Dhote Armament research & development establishment (DRDO) Defence Institute of Advanced Technology

In this article, parametric study of single confined fragment launch device was carried out. The configuration proposed was further studied to derive the empirical relationship for effect of fragment size,charge size, confinement thickness on fragment velocity. The simulations were carried out using ANSYSAUTODYNE explicit solver. Fragment velocities were estimated as a function of different parametric combinations of explosive quantities, charge length to diameter ratio, fragment height to diameter ratio,confinement thickness, fragment material and fragment mass. The data was further converted to charge to metal ratio under fragment and confinement. It was observed that, increase in confinement thickness,charge quantity and decrease in fragment height increases the fragment velocity. It is also noted that,charge to metal mass ratio under fragment significantly affects the fragment velocity. At the end, an empirical relationship for fragment velocity interms of all these parameters was established. Using these relations, two velocities 1831.92 m/s and 2523.9 m/s required for NATO STANAG 4496 IM test were estimated. The design parameters for these velocities are presented. Also, the results estimated using the empirical relationship has been compared with published experimental data. Error in the predicted velocities is within the acceptable range. The empirical relationship proposed will be useful for finalization of design of the fragment launch device.

关键词： Confinement Fragment size Empirical relationship Fragment velocity Insensitive munition test Fragment launching device

Effect of Welding Processes and Consumables on Tensile and Impact Properties of High Strength Quenched and Tempered Steel Joints

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Journal of Iron and Steel research International 2008年第6期15卷 87-94页

作者： G Magudeeswaran V Balasubramanian G Madhusudhan Reddy T S Balasubramanian Center for Advanced Materials Joining and research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Metal Joining Section Defence MetallurgicalResearch Laboratory Special vehicles Division Combat Vehicles Research and Development Establishment

Quenched and tempered steels are prone to hydrogen induced cracking in the heat affected zone after welding. The use of austenitic stainless steel consumables to weld the above steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. In this investigation, an attempt was made to determine a suitable consumable to replace expensive austenitic consumables. Two different consumables, namely, austenitie stain less steel and low hydrogen ferritic steel, were used to fabricate the joints by shielded metal are welding （SMAW） and flux cored arc welding （FCAW） processes. The joints fabricated by using low hydrogen ferritic steel consumables showed superior transverse tensile properties, whereas joints fabricated by using austenitic stainless steel consumables exhibited better impact toughness, irrespective of the welding process used. The SMAW joints exhibited superior mechanical and impact properties, irrespective of the consumables used, than their FCAW counterparts.

关键词： shielded metal arc welding process flux cored arc welding process austenitie stainless steel low hydro gen ferritic steel transverse tensile property impact toughness

Fabrication of AA7005/TiB2-B4C surface composite by friction stir processing: Evaluation of ballistic behaviour

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Defence Technology（防务技术） 2019年第3期15卷 363-368页

作者： Nitinkumar Pol Gaurav Verma R.P.Pandey T.Shanmugasundaram research and development establishment (Engineers) Pune India Department of Metallurgical & Materials Engg. Defence Institute of Advanced Technology Pune India Armament research and development establishment Pune India

The present work aims to enhance the ballistic resistance of AA7005 alloy by incorporating the TiB2 and B4C ceramic reinforcement particles. Surface composites with different weight fractions of TiB2 and B4C particles were processed by friction stir processing. Micro-hardness and depth of penetration tests were carried out to evaluate the ballistic properties of the surface composites. The surface hardness of the composite was found to be nearly 70 HV higher than base alloy. The depth of penetration of the steel projectile was 20e26mm in the composites as compared to 37mm in the base alloy. Ballistic mass efficiency factor of the surface composite was found to be 1.6 times higher than base alloy. This is mainly attributed to the dispersion strengthening from the reinforcement particles.

关键词： Aluminum alloys Metal matrix composite Ballistic testing Friction stir processing

Effect of firing conditions ＆ release height on terminal performance of submunitions and conditions for optimum height of release

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Defence Technology（防务技术） 2017年第3期13卷 200-205页

作者： L.K.Gite A.Anandaraj R.S.Deodhar D.K.Joshi K.M.Rajan Armament research development establishment (ARDE) Defence Research Development Organization Ministry of Defence Government of India

Submunitions should exhibit optimum terminal performance at target end when released from certain pre-determined height. Selection of an optimum height of release of the submunitions depends on the terminal parameters like forward throw, remaining velocity, impact angle and flight time. In this paper,the effects of initial firing conditions and height of release on terminal performance of submunitions discussed in detail. For different height of release, the relation between range and forward throw is also established & validated for a number of firing altitude and rocket configurations.

关键词：最佳高度终端子弹性能射击剩余速度飞行时间冲击角

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli Han Bowen Duan Lei Liu Shilong Fang Weiwei Wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

Self-healing alginate-carboxymethyl chitosan porous scaffold as an effective binder for silicon anodes in lithium-ion batteries

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Rare Metals 2019年第9期38卷 832-839页

作者： Zhao-Hui Wu Juan-Yu Yang Bing Yu Bi-Meng Shi Chun-Rong Zhao Zhang-Long Yu research and development Center for vehicle Battery and Energy Storage General Research Institute for Nonferrous Metals

Polymer binder plays a pivotal role in electrochemical performance of high-capacity silicon(Si)anode that usually suffers from severe capacity fading due to enormous substantial volume change of Si during *** an effort to find efficient polymer binder that could mitigate such capacity fading,alginate-carboxymethyl chitosan(Alg-C-chitosan)composite polymer was investigated as a low-cost watersoluble binder for silicon anodes in lithium-ion *** electrostatic interaction between carboxylate(-COO-)of Alg and protonated amines(-NH3+)of C-chitosan forms a selfhealing porous scaffold *** effect on the enhanced porous scaffold structure and self-healing electrostatic interaction of Alg-C-chitosan binder effectively can tolerate the tremendous volume change of Si and maintain an integrated electrode structure during cycling *** Si nanopowder electrodes with Alg-C-chitosan composite binder exhibit an excellent cycling stability,with a capacity of750 mAh·g-1 remaining after 100 th *** addition,an extraordinary areal capacity of 3.76 mAh·cm-2 is achieved for Si-based anodes with Alg-C-chitosan binder.

关键词： Binder Alginate Carboxymethyl chitosan Self-healing Scaffold Silicon anode

Sarin Induced Lung Pathology and Protection by Standard Therapy Regime

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Biomedical and Environmental Sciences 1993年第2期6卷 103-111页

作者： S.C.PANT R.VIJAYARAGHAVAN S.DASGUPTA Defence DefenceDefence Research & Development EstablishmentGwalior 474002India.Research & Development EstablishmentGwalior 474002India.Research & Development EstablishmentGwalior 474002India.

The effects of atropine, diazepam and pralidoxime were studied for their ability to block the pathological lesions induced by sarin. Rats were exposed to an aerosol of sarin at a concentration of 51.2mg-m for 15 min following the pretreatment with one of the following combinations: atropine (10 mg/kg, i.m.) and diazepam (0.5 mg/kg, i.m.); atropine and pralidoxime (25 mg/kg, i.m.); diazepam and pralidoxime; atropine, diazepam and pralidoxime. Lung exposed to sarin aerosols revealed an increased cellular proliferation with progressive diffused interstitial thickening on the 4th day following exposure. On the 16th day, loss of alveolar space and consolidation of large areas of all lobes were observed. Sarin also caused damage to the respiratory bronchioles. All the therapy regime blocked the development of lung lesions in the descending orders: atropine, diazepam and pralidoxime, atropine and diazepam > diazepam and pralidoxime > atropine and pralidoxime. The result suggests that diazepam in combination with atropine and pralidoxime could be an effective drug combination regime for the lung lesions.

关键词： Sarin Induced Lung Pathology and Protection by Standard Therapy Regime

Idiosyncratic behaviour of(Na_(0.49)5K_(0.455)Li_(0.05))(Nb_(0.95)Ta_(0.05))O_3-La_2O_3 ceramics: Synergistically improved thermal stability, ageing, and fatigue properties

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Journal of Advanced Ceramics 2019年第1期8卷 79-89页

作者： Bhupender RAWAL N. N. WATHORE B.PRAVEENKUMAR H. S. PANDA Armament research and development establishment Department of Materials Engineering Defence Institute of Advanced Technology

La_2 O_3 doped(Na0.495 K0.455 Li0.05)(Nb0.95 Ta0.05)O_3 ceramics are prepared using modified milling process, and the influences of La2 O3 on ferroelectric behaviour, ageing characteristics, thermal stability, electrical stability, crystal structure, microstructure, dielectric and piezoelectric properties were reported. La_2 O_3 addition improved the ferroelectric characteristic substantially, and obtained remnant polarization(Pr) and maximum strain(Smax) around 34.3 C/cm^2 and 0.13% ***_2 O_3 doped ceramics improved the thermal stability and were stable up to 180 ℃ compared to undoped ceramics(120 ℃). The Rietveld refinement along with the high-temperature X-ray diffraction studies suggested the presence of monoclinic phase in La doped compositions, which is responsible for their idiosyncratic behaviour. The maximum values were obtained around 179 pC/N and 0.385 for piezoelectric constant(d33) and electromechanical coupling factor(kp) respectively in La_2 O_3 doped samples(0.02 wt%), which also exhibited the lowest ageing rate and stable electrical fatigue behaviour.

关键词： dielectric fatigue piezoelectric thermal stability