|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Recent advances in catalytic combustion of AP-based composite solid propellants显示文摘Composite solid propellants(CSPs) have widely been used as main energy source for propelling the rockets in both space and military applications. Internal ballistic parameters of rockets like characteristic exhaust velocity, specific impulse, thrust, burning rate etc., are measured to assess and control the performance of rocket motors. The burn rate of solid propellants has been considered as most vital parameter for design of solid rocket motors to meet specific mission requirements. The burning rate of solid propellants can be tailored by using different constituents, extent of oxidizer loading and its particle size and more commonly by incorporating suitable combustion catalysts. Various metal oxides(MOs),complexes, metal powders and metal alloys have shown positive catalytic behaviour during the combustion of CSPs. These are usually solid-state catalysts that play multiple roles in combustion of CSPs such as reduction in activation energy, enhancement of rate of reaction, modification of sequences in reaction-phase, influence on condensed-phase combustion and participation in combustion process in gas-phase reactions. The application of nanoscale catalysts in CSPs has increased considerably in recent past due to their superior catalytic properties as compared to their bulk-sized counterparts. A large surface-to-volume ratio and quantum size effect of nanocatalysts are considered to be plausible reasons for improving the combustion characteristics of propellants. Several efforts have been made to produce nanoscale combustion catalysts for advanced propellant formulations to improve their energetics. The work done so far is largely scattered. In this review, an effort has been made to introduce various combustion catalysts having at least a metallic entity. Recent developments of nanoscale combustion catalysts with their specific merits are discussed. The combustion chemistry of a typical CSP is briefly discussed for providing a better understanding on role of combustion catalysts in burning rate enhancement. Available information on different types of combustion nanocatalysts is also presented with critical comments. | Narendra Yadav Prem Kumar Srivastava Mohan Varma | 2021 | Defence Technology(防务技术)2021，17，3： | 8 |
| 2 | Cu–Co–O nano-catalysts as a burn rate modifier for composite solid propellants显示文摘Nano-catalysts containing copper–cobalt oxides(Cu–Co–O) have been synthesized by the citric acid(CA) complexing method. Copper(II) nitrate and Cobalt(II) nitrate were employed in different molar ratios as the starting reactants to prepare three types of nano-catalysts. Well crystalline nano-catalysts were produced after a period of 3 hours by the calcination of CA–Cu–Co–O precursors at 550 °C. The phase morphologies and crystal composition of synthesized nano-catalysts were examined using Scanning Electron Microscope(SEM), Energy Dispersive Spectroscopy(EDS) and Fourier Transform Infrared Spectroscopy(FTIR) methods. The particle size of nano-catalysts was observed in the range of 90 nm–200 nm. The prepared nano-catalysts were used to formulate propellant samples of various compositions which showed high reactivity toward the combustion of HTPB/AP-based composite solid propellants. The catalytic effects on the decomposition of propellant samples were found to be significant at higher temperatures. The combustion characteristics of composite solid propellants were significantly improved by the incorporation of nano-catalysts. Out of the three catalysts studied in the present work, Cu Co-I was found to be the better catalyst in regard to thermal decomposition and burning nature of composite solid propellants. The improved performance of composite solid propellant can be attributed to the high crystallinity, low agglomeration and lowering the decomposition temperature of oxidizer by the addition of Cu Co-I nano-catalyst. | D. Chaitanya Kumar RAO Narendra YADAV Puran Chandra JOSHI | 2016 | Defence Technology(防务技术)2016，12，4： | 3 |
| 3 | PSO Based Multi-Objective Approach for Controlling PID Controller显示文摘CSTR(Continuous stirred tank reactor)is employed in process control and chemical industries to improve response characteristics and system efficiency.It has a highly nonlinear characteristic that includes complexities in its control and design.Dynamic performance is compassionate to change in system parameterswhich need more effort for planning a significant controller for CSTR.The reactor temperature changes in either direction from the defined reference value.It is important to note that the intensity of chemical actions inside the CSTR is dependent on the various levels of temperature,and deviation from reference values may cause degradation of biomass quality.Design and implementation of an appropriate adaptive controller for such a nonlinear system are essential.In this paper,a conventional Proportional Integral Derivative(PID)controller is designed.The conventional techniques to deal with constraints suffer severe limitations like it has fixed controller parameters.Hence,A novel method is applied for computing the PID controller parameters using a swarm algorithm that overcomes the conventional controller’s limitation.In the proposed technique,PID parameters are tuned by Particle Swarm Optimization(PSO).It is not easy to choose the suitable objective function to design a PID controller using PSO to get an optimal response.In this article,a multi-objective function is proposed for PSO based controller design of CSTR. | Harsh Goud Prakash Chandra Sharma Kashif Nisar Ag.Asri Ag.Ibrahim Muhammad Reazul Haque Narendra Singh Yadav Pankaj Swarnkar Manoj Gupta Laxmi Chand | 2022 | Computers, Materials & Continua2022，，6： | 1 |
| 4 | 节拍化疗治疗ABC型弥漫大B细胞淋巴瘤累及十二指肠降部致梗阻性黄疸一例显示文摘患者女,64岁,因“确诊弥漫大B细胞淋巴瘤5年,黑便1月余”入院。5年前因“发现右侧腹股沟淋巴结肿大”于外院就诊,2013年3月19日行腹股沟淋巴结切除活检术,病理结果示(右腹股沟)弥漫大B细胞淋巴瘤(DLBCL,ABC型)。免疫组织化学检查示CD10(-)、Bcl-6(-)、Bcl-2(+)、Ki-67(+80%)、CD3(+)、CD20(+++),行R-CHOP方案(利妥昔单抗、环磷酰胺、多柔比星、长春新碱、泼尼松)化疗6个疗程,50 Gy放疗17次,病情缓解后出院,后定期复查超声,全身浅表淋巴结均无明显肿大。后患者于2018年2月1日无明显诱因开始出现黑便,于外院行内镜检查结果示慢性非萎缩性胃炎;十二指肠降段新生物病理组织活检结果示(十二指肠降段及胃小弯侧)小块挤压明显,DLBCL(ABC型);免疫组化检查结果示PCK(-)、HBM45(-)、CD21(-)、MUM-1(+)、CD10(-)、Bcl-6(-)、Bcl-2(+)、Ki-67(+80%)、ALK(-)、EMA(-)、CD3(+)、CD20(+++),考虑为DLBCL(ABC型)复发。 | 桂成思 刘尚勤 Narendra Prasad Yadav | 2021 | 临床内科杂志2021，38，10： | 1 |
| 5 | Performance Comparison and Analysis of Table-Driven and On-Demand Routing Protocols for Mobile Ad-hoc Networks 显示文摘 | NARENDRA S Y YADAV R P | 2007 | International Journal of Information Technology2007，，2： | 1 |
| 6 | A phase II study of neoadjuvant chemotherapy followed by organ preservation in patients with muscle-invasive bladder cancer显示文摘Objective:Conservative approaches in muscle-invasive bladder cancer(MIBC)have been evolved to avoid aggressive surgery,but are limited to elderly,frail,and patients medically unfit for surgery.Our study aimed to assess the response rate of neoadjuvant chemotherapy(NACT)before radiotherapy(RT)in MIBC patients.Methods:Forty patients with urothelial carcinoma of stage T2-T4a,N0,M0 were enrolled between November 2013 and November 2015,and treated with three cycles of NACT with gemcitabine-cisplatin.Post-NACT response was assessed using Response Evaluation Criteria in Solid Tumors(RECIST)criteria.Patients who achieved complete response(CR)and partial response(PR)>50%were treated with radical RT,and those who had PR<50%,stable disease(SD),and progressive disease(PD)underwent radical cystectomy(RC).Survival analysis was done with Kaplan-Meier method and point-to-time events were analyzed with Cox-proportional hazards regression model.Results:After NACT,35(87.5%)patients achieved either PR>50%or CR,and were treated with RT.Five(12.5%)patients who had PR<50%,SD,or PD underwent RC.All patients who received radiation showed CR after 6 weeks.Median follow-up was 43 months(range:10-66 months)and median overall survival(OS)was not reached.Three-year OS,local control,and disease-free survival were 70.1%,60.9%,50.6%,respectively,and 50%of patients preserved their functioning bladder.Three-year OS rate was 88.9%in patients who achieved CR to NACT,73.1%in patients with PR≥50%and 40%in patients with PR<50%.Conclusion:NACT followed by RT provides a high probability of local response with bladder preservation in CR patients.Appropriate use of this treatment regimen in carefully selected patients may omit the need for morbid surgery. | Chinna Babu Dracham Narendra Kumar Santosh Kumar Arun Elangovan Budhi Singh Yadav Ravimohan S.Mavuduru Anupam Lal Pramod K.Gupta Rakesh Kapoor | 2022 | Asian Journal of Urology2022，9，3： | 1 |
| 7 | Metaheuristics Algorithm for Tuning of PID Controller of Mobile Robot System显示文摘Robots in the medical industry are becoming more common in daily life because of various advantages such as quick response,less human interference,high dependability,improved hygiene,and reduced aging effects.That is why,in recent years,robotic aid has emerged as a blossoming solution to many challenges in the medical industry.In this manuscript,meta-heuristics(MH)algorithms,specifically the Firefly Algorithm(FF)and Genetic Algorithm(GA),are applied to tune PID controller constraints such as Proportional gain Kp Integral gain Ki and Derivative gain Kd.The controller is used to control Mobile Robot System(MRS)at the required set point.The FF arrangements are made based on various pre-analysis.A detailed simulation study indicates that the proposed PID controller tuned with Firefly Algorithm(FF-PID)for MRSis beneficial and suitable to achieve desired closed-loop system response.The FF is touted as providing an easy,reliable,and efficient tuning technique for PID controllers.The most suitable ideal performance is accomplished with FF-PID,according to the display in the time response.Further,the observed response is compared to those received by applying GA and conventional off-line tuning techniques.The comparison of all tuning methods exhibits supremacy of FF-PID tuning of the given nonlinear Mobile Robot System than GA-PID tuning and conventional controller. | Harsh Goud Prakash Chandra Sharma Kashif Nisar Muhammad Reazul Haque Ag.Asri Ag.Ibrahim Narendra Singh Yadav Pankaj Swarnkar Manoj Gupta Laxmi Chand | 2022 | Computers, Materials & Continua2022，，8： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员