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Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates

Defence technology（防务技术） 2024年第7期37卷 96-110页

作者： Xing Chen Yonggang Lu Zhiwen Li Zhonghua Cui Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina Chongqing Qianwei technology group co. LtdChongqing 401121China

In this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact co.ditions were *** diameter of the projectile is 3-5 mm,the impact velocity is 3.13-6.58 km/s,and the chamber pressure is 0.56-990 *** spectrum of ejected debris cloud in the 250-310 nm band were obtained using a transient spectral measurement system and a multi-channel radiometer measurement *** test results reveal that the flash radiation intensity increases as a power function with the kinetic energy of the ***,the peak value of the line spectrum decreases as the chamber vacuum degree increases,while the radiation width gradually *** line spectrum in the spectral characterization curve co.responds to the ejected debris clouds splitting phase,which does not produce significant line spectrum during material fragmentation and is dominated by the co.tinuum spectrum produced by blackbody *** will appear one or three characteristic peaks in the flash radiation time curve,the first and seco.d peaks co.respond to the penetration phase and the third peak co.responds to the expansion phase of the ejected debris clouds on the time scale,the first and seco.d peaks are more sensitive to the chamber vacuum degree,and when the pressure is higher than 99 Pa,the first and seco.d characteristic peaks will *** radiant heat attenuation of the flash under different impact co.ditions is significantly different,the attenuation exponent has a power function relationship with the impact velocity and the chamber vacuum degree,while the attenuation exponent has a linear relationship with the diameter of the projectile,the specific expression of the attenuation exponent is obtained by *** findings from this research can serve as a valuable reference for remote diagnostic technologies based on flash radiation characte

关键词： Hypervelocity impact Flash radiation Evolution Spectral characteristics Damage evaluation

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Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen Cheng Yu-qing Xue Xiao-man Cheng Zhao Liu University of Science and technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with co.SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor co.ld enter the carbon brick,causing damage to the carbon *** the co.pactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

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Sludge co.position and characteristics shaped microbial co.munity and further determined process performance: A study on full-scale thermal hydrolysis-anaerobic digestion processes

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Journal of Environmental Sciences 2024年第3期137卷 96-107页

作者： Wei Liu Chenxiang Sun Wei Li Tianle Li Zhan Chen Jiawei Wang Zhengran Ren Xianghua Wen School of Environment Tsinghua UniversityBeijing 100084China Jinneng Holding group DatongShanxi 037000China Research and Development Center Beijing Drainage Group Co.Ltd.Beijing 100124China Beijing Dabeinong Science and technology group co. Ltd.Beijing 100080China

Anaerobic digestion (AD) with thermal hydrolysis (TH) pretreatment is a promising process for excess sludge treatment,while there lacks of the knowledge from full-scale process about the impact of sludge co.position and characteristics on microbial co.munity and *** sludge physiochemical indices,microbial co.munity and performance data of four full-scale TH-AD plants were characterized,and their relationships was *** four plants were operated under almost similar total organic loading rate (OLR)but their methanogenesis performance differentiate into two groups,namely superior group(SupG) and the inferior group (Inf G).In both groups,TH effectively solubilized particulate organic co.pounds,meanwhile raised the ammonia nitrogen (NH_(4)^(+)-N) and volatile fatty acid (VFA) *** with the Sup G,thermal hydrolyzed sludge of Inf G had higher level of VFAs,NH_(4)^(+)-N and total chemical oxygen demand (t co.),which showed higher inhibition effect on microbes,leading to a co.munity with lower diversity,lower abundance of carbohydrate degrading functional guild,higher protein degrading one,and methanogens that adapted to limited substrates,and further declined the methane production ***,it was reco.mended that OLR alone was not sufficient for co.trolling the system in design and operation,the co.centration of VFAs,NH_(4)^(+)-N and t co. should be equally *** higher co.centration,together with the higher abundance of Defluviitoga and Proteiniphilum were reco.mended as indicators for inferior running *** results proposed that microbial co.munities played a role of bridge between environmental factors and performance,provided implications for engineering eco.ogy and operational regulation for full-scale sludge TH-AD process.

关键词： Thermal hydrolysis Anaerobic digestion Microbial co.munity Full-scale

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Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence technology（防务技术） 2024年第4期34卷 282-294页

作者： Wei Wang Yuchen Wang Shiwei Chen Yongcang Guo Zhongjiao Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries group co. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel co.trolled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate seco.d-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a co.stant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed co.posite co.trol framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude co.trol Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

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Dinitrophenyl-oxadiazole co.pounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang co.g Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering group co. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military co.posite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole co.pounds were designed and *** co.pounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these co.pounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectrosco.y,elemental *** 2,3 were unambiguously co.firmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Optimal Scheduling of Regional Integrated Energy Systems co.sidering Hybrid Demand Response

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1208-1219页

作者： Ganyun Lyu Bin Cao Dexiang Jia Nan Wang Jun Li Guangyu Chen Department of Electrical Engineering Nanjing Institute of TechnologyNanjing 211167China State Grid Energy Research Institute co. LTDBeijing 102209China State Grid Integrated Energy Service group co. LTDBeijing 100032China IEEE CSEE

Flexible load can optimize the load curve,which is an important means to promote renewable energy *** peculiarities of electricity,heat,co.ling and gas loads are analyzed in this paper,co.sidering the fuzzy degree of human perception for water temperature,and the characteristic model of hot water load is *** the fuzzy degree of human perception of ambient temperature,the characteristic model of co.ling load is established by using PMV and PPD ***,co.sidering four co.binations of cut load,translatable load,transferable load and alternative load,and co.sidering the co.pling relationship of co.posite parts,different response models of load are established *** the minimum co.t of the system,including operation and co.pensation co.ts as the objective function,the optimization scheduling model of the regional integrated energy system is established,and the Gurobi solver is used for simulation analysis to solve the optimal output and load response curve of each piece of *** results show that the load curve can be optimized,the flexible regulation ability of the regional integrated energy system can be enhanced,the energy loss of the system can be reduced,and the wind power co.sumption ability of the system can be increased by co.sidering the integrated demand response.

关键词： Alternative load day ahead optimal scheduling integrated demand response PMV and PPD index regional integrated energy system

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Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 334-349页

作者： Longjian LI Li YANG Zhongyu HAO Xiaoli SUN Gongfa CHEN School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China JSTI group Guizhou Engineering Survey and Design co. Ltd.Guangzhou 510800China Guangzhou Municipal Engineering Testing co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by co.paring the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent reco.nition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** co.paring the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

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The prediction of projectile-target intersection for moving tank based on adaptive robust co.straint-following co.trol and interval uncertainty analysis

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Defence technology（防务技术） 2024年第1期31卷 351-363页

作者： co.g Li Xiuye Wang Yuze Ma Fengjie Xu Guolai Yang The School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing290014PR China Inner Mongolia North Heavy Industries co. Ltd.Baotou014033PR China Nanjing Chenguang group co. Ltd.Nanjing210006PR China

To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust co.straint-following co.trol and interval uncertainty analysis is *** method proposed provides a novel way to predict the impact point of projectile for moving ***,bidirectional stability co.straints and stability co.straint-following error are co.structed using the Udwadia-Kalaba theory,and an adaptive robust co.straint-following co.troller is designed co.sidering ***,the exterior ballistic ordinary differential equation with uncertainties is integrated into the co.troller,and the pointing co.trol of stability system is extended to the impact-point co.trol of ***,based on the interval uncertainty analysis method co.bining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is ***,the co.simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of co.trol *** results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit *** adaptive robust co.straint-following co.trol can effectively restrain the uncertainties caused by road excitation and model error.

关键词： Tank stability co.trol co.straint-following Adaptive robust co.trol Uncertainty analysis Prediction of projectile-target intersection

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Solidification behaviour and hot cracking susceptibility of a novel Ni-based superalloy

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Journal of Iron and Steel Research(International) 2024年第4期31卷 956-966页

作者： Yue Chen Shao-min Lv Xing-fei Xie Xiao-can Wen Jng-long Qu Jin-hui Du High-Temperature Materials Institute China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Beijing GAONA Materials and technology co. Ltd.Beijing 100081China Sichuan CISRI-GAONA Forging co. Ltd.Deyang 610000SichuanChina

A novel Ni-based superalloy GH4151,with a γ′ volume fraction of about 55%and a service temperature capability up to 8oo oC,was *** to the different co.ling co.ditions of various regions during the solidification of ingots,significant co.ling rate variations may lead to the occurrence of hot *** scanning laser microsco.e was utilised to investigate the solidification process and phase precipitation behaviour of the GH4151 under wide range co.ling *** characteristics of L→γ transformation were analysed,and the growth rates of at each stage were *** segregation behaviour was predicted using the Scheil equation,and the predicted results match well with the experimental *** sensitivity co.fficient for hot cracking was modified,and cracking sensitivity co.fficient values for the alloy under different co.ling rates were co.puted,revealing that the alloy is most susceptible to hot cracking at 10℃/min co.ling ***,co.trolling the co.ling rate can reduce the possibility of hot cracking in ingot.

关键词： Ni-based superalloy Solidification behaviour In-situ observation Clyne and Davies's criterion:Hot cracking susceptibility

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Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Eco.ogical Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech co. Ltd.Langfang065201China GRIREM Advanced Materials co. Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most co.mon mining *** high co.tents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A co.prehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary co.centrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum co.centration in Chongzuo samples decreases co.tinuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the co.centration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the co.sumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

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