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火炸药学报 2024年第3期47卷 209-219,I0003页

作者： Mohammed Dourari Ahmed Fouzi Tarchoun Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria Xi′an Modern Chemistry Research Institute Xi′an 710065China

The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been *** catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been *** characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic *** is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat *** models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of ***,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants.

关键词： triaminoguanidine transition metal complexes nitrocellulose diethylene glycol dinitrate catalytic effect

Evaluating Ignition and Combustion Performance with Al-Metal- Organic Frameworks and Nano-Aluminum in HTPB Fuel

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火炸药学报 2024年第5期47卷 413-421,I0003页

作者： Sri Nithya Mahottamananda Yash Pal Yarravarapu Sai Sriram Subha S Djalal Trache Department of Aerospace Engineering B S Abdur Rahman CrescentInstitute of Science and TechnologyChennai-600048India School of Aeronautical Science Hindustan Institute of Technologyand ScienceChennai-603103India Energetic Materials Laboratory(EMLab) Teaching and ResearchUnit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria

Incorporating aluminum metal-organic frameworks(Al-MOFs)as energetic additives for solid fuels presents a promising avenue for enhancing combustion *** study explores the potential benefits of Al-MOF(MIL-53(Al))energetic additive on the combustion performance of hydroxyl-terminated polybutadiene(HTPB)*** HTPB-MOF fuel samples were manufactured using the vacuum-casting technique,followed by a comprehensive evaluation of their ignition and combustion properties using an opposed flow burner(OFB)setup utilizing gaseous oxygen as an *** gauge the effectiveness of Al-MOFs as fuel additives,their impact is compared with that of nano-aluminum(nAl),another traditional additive in HTPB *** results indicate that the addition of 15%(mass fraction)nAl into HTPB resulted in the shortest ignition delay time(136 ms),demonstrating improved ignition performance compared to pure HTPB(273 ms).The incorporation of Al-MOF in HTPB also reduced ignition delay times to 227 ms and 189 ms,***,under high oxidizer mass flux conditions(79—81 kg/(m^(2)s)),HTPB fuel with 15%nAl exhibited a substantial 83.2%increase in regression rate compared to the baseline HTPB fuel,highlighting the positive influence of nAl on combustion *** contrast,HTPB-MOF with a 15%Al-MOF additive showed a 32.7%increase in regression rate compared to pure *** results suggest that HTPB-nAl outperforms HTPB-MOF in terms of regression rates,indicating a more vigorous and rapid burning behavior.

关键词： ignition combustion enhancement MOF HTPB regression rate

Unraveling the role of dual Ti/Mg metals on the ignition and combustion behavior of HTPB-boron-based fuel

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Defence Technology（防务技术） 2024年第2期32卷 134-143页

作者： Arijit Debnath Yash Pal Sri Nithya Mahottamananda Djalal Trache School of Aeronautical Science Hindustan Institute of Technology and ScienceChennai 603103India Department of Aerospace Engineering B S Abdur Rahman Crescent Institute of Science and TechnologyChennai 600048India Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria

Metal additives play an essential role in explosive and propellant formulations. Boron(B) is widely used in propellant applications owing to its high energetic content. The addition of B to explosives and propellants increases their energy density, making them more efficient and powerful. Nevertheless, B forms oxide layers on its surface during combustion, slowing down the combustion rate and reducing rocket motor efficiency. To overcome this issue, other metal additives such as aluminum(Al), magnesium(Mg),and titanium(Ti) are revealed to be effective in boosting the combustion rate of propellants. These additives may improve the combustion rate and therefore enhance the rocket motor’s performance. The present study focused on preparing and investigating the ignition and combustion behavior of pure hydroxyl-terminated polybutadiene(HTPB)-B fuel supplemented with nano-titanium and nanomagnesium. The burn rates of HTPB-B fuel samples were evaluated on the opposed flow burner(OFB)under a gaseous oxygen oxidizer, for which the mass flux ranges from 22 kg/(m^(2)·s) to 86 kg/(m^(2)·s). The addition of Ti and Mg exhibited higher regression rates, which were attributed to the improved oxidation reaction of B due to the synergetic metal combustion effect. The possible combustion/oxidation reaction mechanism of B-Mg and B-Ti by heating the fuel samples at 900℃ and 1100℃ was also examined in a Nabertherm burnout furnace under an oxygen atmosphere. The post-combustion products were collected and further subjected to X-ray diffraction(XRD) and field emission scanning electron microscopy(FE-SEM) analyses to inspect the combustion behavior of B-Ti and B-Mg. It has been observed that the B oxide layer at the interface between B-Ti(B-Mg) is removed at lower temperatures, hence facilitating oxygen transfer from the surroundings to the core B. Additionally, Ti and Mg decreased the ignition delay time of B, which improved its combustion performance.

关键词： Boron B_(2)O_(3) Opposed flow burner Combustion Magnesium

Virtual Transmission Solution Based on Battery Energy Storage Systems to Boost Transmission Capacity

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 466-474页

作者： Matías Agüero Jaime Peralta Eugenio Quintana Victor Velar Anton Stepanov Hossein Ashourian Jean Mahseredjian Roberto Cárdenas Coordinador Eléctrico Nacional SantiagoChile PGSTech Montreal Canada ecole polytechnique de Montréal Montréal Canada University of Chile Santiago Chile IEEE

The increasing penetration of variable renewable energy(VRE)generation along with the decommissioning of conventional power plants in Chile,has raised several operational challenges in the Chilean National Power Grid(NPG),including transmission congestion and VRE *** mitigate these limitations,an innovative virtual transmission solution based on battery energy storage systems(BESSs),known as grid booster(GB),has been proposed to increase the capacity of the main 500 kV corridor of the *** paper analyzes the dynamic performance of the GB using a wide-area electromagnetic transient(EMT)model of the *** GB project,composed of two 500 MVA BESS units at each extreme of the 500 kV corridor,allows increasing the transmission capacity for 15 min during N-1 contingencies,overcoming transmission limitations under normal operation conditions while maintaining system stability during *** dynamic behavior of the GB is also analyzed to control power flow as well as voltage *** results show that the GB is an effective solution to allow greater penetration of VRE generation while maintaining system stability in the NPG.

关键词： Battery energy storage system(BESS) grid booster transient stability voltage stability electromagnetic transient(EMT)

Actuating droplets with electrowetting: Force and dynamics

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Droplet 2024年第2期3卷 113-124页

作者： Robert Hennig Vito Cacucciolo Herbert Shea Soft Transducers Laboratory(LMTS) Ecole Polytechnique Fédérale de Lausanne(EPFL)NeuchatelSwitzerland Politecnico di Bari BariItaly

Electrowetting on dielectric(EWOD)allows rapid movement of liquid droplets on a smooth surface,with applications ranging from lab-on-chip devices to *** in-plane force on a droplet is a key indicator of EWOD *** force has been extensively modeled but few direct experimental measurements are *** study the EWOD force on a droplet using two setups that allow,for the first time,the simultaneous measurement of force and contact angle,while imaging the droplet shape at 6000 frames/*** several liquids and surfaces,we observe that the force saturates at a voltage of approximately 150 *** of voltages of up 2 kV,that is,10 times higher than is typical,does not significantly increase forces beyond the saturation ***,we observe that the transient dynamics,localized at the front contact line,do not show saturation with *** the higher voltages,the initial front contact line speed continues to increase,the front contact angle temporarily becomes near zero,creating a thin liquid film,and capillary waves form at the liquid–air *** the localized EWOD forces at the contact line exceed the capillary forces,projectile droplets *** surface tension allows for higher droplet forces,which we demonstrate with mercury.

关键词： capillary forces dynamics

Synthesis and characterization of a 1,3-dibutylimidazolium azide([BBIm][N_(3)]) : A promising green energetic ionic liquid

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Defence Technology（防务技术） 2024年第8期38卷 1-15页

作者： Nawel Matmat Amir Abdelaziz Djalal Trache Achour Sabrina Ahmed Fouzi Tarchoun Hani Boukeciat Sourbh Thakur Weiqiang Pang Thomas M.Klapotke Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17 Bordj El-BahriAlgiers 16046Algeria Department of Organic Chemistry Bioorganic Chemistry and BiotechnologySilesian University of TechnologyB.Krzywoustego 444-100 GliwicePoland Xi'an Modern Chemistry Research Institute Xi'an 710065China Energetic Materials Research Department of ChemistryLudwig-Maximilian UniversityMunich Butenandtstrasse 5-13(D)D-81377 MunichGermany

In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in this ionic liquids *** chemical structure of this EIL was rigorously characterized and confirmed using FTIR spectroscopy,1D,and 2D-NMR *** thermal behavior assessment was conducted through DSC and TGA *** analysis revealed an endothermic glass transition at T_(g)=-61℃,followed by an exothermic degradation event at T_(onset)=311℃.Similarly,TGA thermograms exhibited a one-stage decomposition process resulting in 100% mass loss of the ***,the short-term thermal stability of the azide EIL was investigated by combining the non-isothermal TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic ***,the Arrhenius parameters(E_(a)=154 kJ·mol^(-1),Log(A/s^(-1))=11.8) and the most probable reaction model g(a) were *** observed high decomposition temperatures and the significantly elevated activation energy affirm the enhanced thermal stability of the modified *** findings revealed that[BBIm][N_(3)]EIL can be a promising candidate for advanced energetic material application.

关键词： 1,3-dibutyl-imidazolium azide[BBIm][N_(3)] Energetic imidazolium-base ionic liquids 1D-/2D-NMR analyses Short-term thermal stability Isoconversional approaches

Predicting plant disease epidemics using boosted regression trees

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Infectious Disease Modelling 2024年第4期9卷 1138-1146页

作者： Chun Peng Xingyue Zhang Weiming Wang School of Mathematics and Statistics Huaiyin Normal UniversityHuaian223300PR China ecole polytechnique Federale de Lausanne Rte Cantonale1015LausanneSwitzerland

Plant epidemics are often associated with weather-related *** is difficult to identify weather-related predictors for models predicting plant *** the article by Shah et al.,to predict Fusarium head blight(FHB)epidemics of wheat,they explored a functional approach using scalar-on-function regression to model a binary outcome(FHB epidemic or non-epidemic)with respect to weather time series spanning 140 days relative to *** scalar-on-function models fit the data better than previously described logistic regression *** this work,given the same dataset and models,we attempt to reproduce the article by Shah et *** a different approach,boosted regression *** fitting,the classification accuracy and model statistics are surprisingly good.

关键词： Plant disease epidemics Scalar-on-function model Boosted regression trees

Guillaume Broux-Quemerais,Sarah Kaakai, Anis Matoussi,Wissal Sabbagh

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Probability, Uncertainty and Quantitative Risk 2024年第2期9卷 149-180页

作者： Guillaume Broux-Quemerais Sarah Kaakarl Anis Matoussi Wissal Sabbagh Laboratoire Manceau de Mathematiques&FR CNRS No 2962 Institut du Risque et de I'AssuranceLeMansUniversityFrance Centre de Mathématiques Appliquees(CMAP) CNRSEcole polytechniqueInstitut Polytechnique de Paris91120 PalaiseauFrance

In this paper,we present a probabilistic numerical method for a class of forward utilities in a stochastic factor *** this purpose,we use the representation of forward utilities using the ergodic Backward Stochastic Differential Equations(eBSDEs)introduced by Liang and Zariphopoulou in[27].We establish a connection between the solution of the ergodic BSDE and the solution of an associated BSDE with random terminal time T,defined as the hitting time of the positive recurrent stochastic *** viewpoint based on BSDEs with random horizon yields a new characterization of the ergodic cost^which is a part of the solution of the *** particular,for a certain class of eBSDEs with quadratic generator,the Cole-Hopf transformation leads to a semi-explicit representation of the solution as well as a new expression of the ergodic cost>.The latter can be estimated with Monte Carlo *** also propose two new deep learning numerical schemes for ***,we present numerical results for different examples of eBSDEs and forward utilities together with the associated investment strategies.

关键词： Deep leaming scheme Forward utilities Ergodic BSDEs Markovian solution Deep learning algorithm

The Role and Place of Artificial Neural Network Architectures Structural Redundancy in the Input Data Prototypes and Generalization Development

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Journal of Computer and Communications 2024年第7期12卷 1-11页

作者： Conrad Onésime Oboulhas Tsahat Ngoulou-A-Ndzeli Béranger Destin Ossibi ecole Nationale Suprieure polytechnique Universit Marien Ngouabi Brazzaville Republic of Congo

Neural Networks (NN) are the functional unit of Deep Learning and are known to mimic the behavior of the human brain to solve complex data-driven problems. Whenever we train our own neural networks, we need to take care of something called the generalization of the neural network. The performance of Artificial Neural Networks (ANN) mostly depends upon its generalization capability. In this paper, we propose an innovative approach to enhance the generalization capability of artificial neural networks (ANN) using structural redundancy. A novel perspective on handling input data prototypes and their impact on the development of generalization, which could improve to ANN architectures accuracy and reliability is described.

关键词： Multilayer Neural Network Multidimensional Nonlinear Interpolation Generalization by Similarity Artificial Intelligence Prototype Development

Remote electric powering by germanium photovoltaic conversion of an Erbium-fiber laser beam

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Chip 2024年第3期3卷 15-20页

作者： Richard Soref Francesco De Leonardis Oussama Moutanabbir Gerard Daligou Engineering Department University of Massachusetts at BostonBostonMA 02125USA Department of Electrical and Information Engineering Politecnico di BariBari 70121-70132Italy Department of Engineering Physics Ecole Polytechnique de MontrealMontrealQuebec 999040Canada

The commercially available 4000-Watt continuous-wave(CW)Erbium-doped-fiber laser,emitting at the 1567-nm wavelength where the atmosphere has high transmission,provides an opportunity for harvesting electric power at remote“off the grid”locations using a multi-module photovoltaic(PV)“receiver”*** paper proposes a 32-element monocrystalline thick-layer Germanium PV panel for efficient harvesting of a collimated 1.13-m-diam *** 0.78-m^(2) PV panel is constructed from commercial Ge *** incident CW laser-beam power in the 4000 to 10,000 W range,our thermal,electrical,and infrared simulations predict 660 to 1510 Watts of electrical output at the panel temperatures of 350 to 423 K.

关键词： Laser power transmission Photovoltaic panels Germa-nium infrared detection Erbiumﬁber laser Ytterbiumﬁber laser Directed-beam energy harvesting