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Preparation of ammonium nitrate-based solid composite propellants supplemented with polyurethane/nitrocellulose blends binder and their thermal decomposition behavior

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Defence Technology（防务技术） 2022年第11期18卷 2023-2033页

作者： Sabri Touidjine Moulai Karim Boulkadid Djalal Trache Samir Belkhiri Abderrahmane Mezroua Mohamed Islam Aleg Afaf Belkebiche Energetic Propulsion Laboratory Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj-El-Bahri16046AlgiersAlgeria Energetic Materials Laboratory Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj-El-Bahri16046AlgiersAlgeria

To improve the performance of solid composite propellants(SCPs)supplemented with ammonium nitrate(AN)as an oxidizer,the incorporation of energetic ingredients such as explosives,energetic binders or catalysts is a common effective *** this purpose,polyurethane(PU),a typical inert binder,was mixed with nitrocellulose(NC)as an energetic *** composite solid propellant compositions based on AN and NC-modified polyurethane binder with different NC ratios were *** prepared formulations were characterized using Fourier transform infrared spectroscopy(FTIR),RAMAN spectroscopy,X-ray diffraction(XRD),electron densimetry,thermogravimetric(TG)analysis,and differential scanning calorimetry(DSC).A kinetic study was then performed using the iterative KissingerAkahira-Sunose(It-KAS),Flynn-Wall-Ozawa(It-FWO),and non-linear Vyazovkin integral with compensation effect(VYA/CE)*** theoretical performances,such as theoretical specific impulse,adiabatic flame temperature,and ideal exhaust gaseous species,were also determined using the NASA Lewis Code,Chemical Equilibrium with Application(CEA).Spectroscopic examinations revealed the existence of NC and full polymerization of PU in the prepared *** to density tests,the density of the propellant increases as the nitrocellulose component *** to the thermal analysis and kinetics study,the increase in NC content catalyzed the thermal decomposition of the AN-based composite solid *** on the theoretical study,increasing the amount of NC in the propellant increased the specific impulse and,as a result,the overall performance.

关键词： Composite propellants Polyurethane Nitrocellulose Ammonium nitrate Decomposition kinetics Thermal decomposition

BioMinE:An integrated project for developing biohydrometallurgy in Europe——Executive summary of its activities and outputs after three years

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中国有色金属学会会刊：英文版 2008年第6期18卷 1328-1335页

作者： Dominique H.R.MORIN BRGM-EPI/Eco 3Avenue C.Guillemin-BP 600945060 Orléans Cedex 2France

Biohydrometallurgy 是生物工学和冶金学的意外联合的后代。从某极端 biotopes 的特定的性质，在微生物引起的新陈代谢和矿物质之间的相互作用的活跃原则被提取了被用作有效冶金过程。许多有利工业操作基于这些 bioprocesses 一直在跑... 详细信息

Biohydrometallurgy 是生物工学和冶金学的意外联合的后代。从某极端 biotopes 的特定的性质，在微生物引起的新陈代谢和矿物质之间的相互作用的活跃原则被提取了被用作有效冶金过程。许多有利工业操作基于这些 bioprocesses 一直在跑例如恢复铜，黄金，铀或钴，许多另外的应用程序被设计了。欧洲在这个区域在是相当活跃的过去，但是当前领导在南非，美洲和澳大利亚。BioMinE (在欧洲的忍受金属的材料的生物工学) 是与欧洲 Commision 的支持发射的一个大综合工程。它针对刺激在在这个技术领域里开发新概念的最相关的大学，研究和工业组织之间的协同作用以后允许矿物质资源的更好的利用。当他们识别了需要从今天并且明天的资源为金属抽取发现新过程，欧洲非铁的金属采矿工业开始了并且发展 BioMinE 工程。

关键词：生物显微冶金术生物技术欧洲活性

Potassium sources, microorganisms and plant nutrition: Challenges and future research directions

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Pedosphere 2023年第1期33卷 105-115页

作者： Abdoulaye SOUMARE Djibril SARR Abdala G.DIÉDHIOU UFR ST Departement of AgroforestryAssane Seck University of Ziguinchor(UASZ)Ziguinchor BP 523Senegal Laboratoire Commun de Microbiologie(LCM) IRD/ISRA/UniversitéCheikh Anta Diop(UCAD)Centre de Recherche de Bel AirDakar BP 1386Senegal Centre d’Excellence Africain en Agriculture pour la SécuritéAlimentaire et Nutritionnelle(CEA-AGRISAN) UCADDakar BP 5005Senegal Département de Biologie Végétale Facultédes Sciences et TechniquesUCADDakar BP 5005Senegal

Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this *** addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped *** results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus *** compensate for these losses,massive use of K fertilizers in agriculture has been *** fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic ***-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable *** possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by *** this review,the existing forms of K in soils and their availability and dynamic equilibrium are *** addition,different K fertilizers and their advantages and disadvantages for crops are ***,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are *** and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and *** review may serve as a proposal for the future research avenues identified here.

关键词： biofertilizer crop production organic acid K solubilization K-solubilizing microorganisms rock minerals

Multimodel Approach for Intelligent Control and Applications

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Journal of Donghua University(English Edition) 2004年第3期21卷 15-20页

作者： Abdelkader El Kamel Pierre Borne Ecole Centrale de Lille LAIL BP: 48 F59651 Villeneuve d' Ascq Cedex FranceEcole Centrale de Lille LAIL BP: 48 F59651 Villeneuve d' Ascq Cedex France

The use of the multimodel approach in the modelling, analysis and control of non-linear complex and/or ill-defined systems was advocated by many researchers. This approach supposes the definition of a set of local models valid in a given region or domain. Different strategies exist in the literature and are generally based on a partitioning of the non-linear system’s full range of operation into multiple smaller operating regimes each of which is associated with a locally valid model or controller. However, most of these strategies, which suppose the determination of these local models as well as their validity domain, remain arbitrary and are generally fixed thanks to a certain a priori knowledge of the system whatever its order. Recently, we have proposed a new approach to derive a multimodel basis which allows us to limit the number of models in the basis to almost four models. Meanwhile, the transition problem between the different models, which may use either a simple commutation or a fusion technique, remains still arise. In this plenary talk, a fuzzy fusion technique is presented and has the following main advantages: （1） use of a fuzzy partitioning in order to determine the validity of each model which enhances the robustness of the solution; 2 introduction, besides the four extreme models, of another model, called average model, determined as an average of the boundary models.

关键词： multimodel fuzzy fusion average model

Time-varying nexus and causality in the quantile between Google investor sentiment and cryptocurrency returns

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Blockchain(Research and Applications) 2024年第2期5卷 1-12页

作者： Fatma Ben Hamadou Taicir Mezghani Mouna Boujelbene Abbes Faculty of Economics and Management of Sfax Laboratory URECASfax UniversityBP1169.3029SfaxTunisia

Understanding the interplay between investor sentiment and cryptocurrency returns has become a critical area of ***,this study aims to uncover the role of Google investor sentiment on cryptocurrency returns(including Bitcoin,Litecoin,Ethereum,and Tether),especially during the 2017-18 bubble(January 01,2017,to December 31,2018)and the COVID-19 pandemic(January 01,2020,to March 15,2022).To achieve this,we use two techniques:quantile causality and wavelet ***,the quantile causality test revealed that investors’optimistic sentiments have notably higher cryptocurrency returns,whereas pessimistic sentiments have significantly opposite ***,the wavelet coherence analysis shows that co-movement between investor sentiment and Tether cannot be considered *** result supports the role of Tether as a stablecoin in portfolio diversification *** fact,the findings will help investors improve the accuracy of cryptocurrency return forecasts in times of stressful events and pave the way for enhanced decision-making utility.

关键词： Cryptocurrency COVID-19 pandemic Wavelet coherence Causality-in-quantile approach Google trends

第二十一届世界石油大会bp公司发布《2014世界能源统计年鉴》——通过客观的能源市场数据、对全球能源市场变化及发展动态给予了评述

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世界石油工业 2014年第4期21卷 12-19页

作者：克里斯托夫·鲁尔 bp

2013年，全球石油消费总量9133万bbl／d，生产总量8681万bbl／d，生产特点表现为美国的创纪录增长及北非和中东地区部分国家严重的供应减产；全球炼油总能力9495万bbl／d，增量主要来自中国和沙特；全球天然气消费量53476亿m3。产量3390... 详细信息

2013年，全球石油消费总量9133万bbl／d，生产总量8681万bbl／d，生产特点表现为美国的创纪录增长及北非和中东地区部分国家严重的供应减产；全球炼油总能力9495万bbl／d，增量主要来自中国和沙特；全球天然气消费量53476亿m3。产量33905亿m3，贸易量1033．9亿m3；全球煤炭消费量38．27亿t油当量，各区域价格均出现下跌；非化石燃料增长超出平均水平，在全球发电量中的比重几乎达到1／3，可再生能源是其增长的最大动力。全球贸易失衡是过去10年影响全球经济的潜在因素，通过减少美国赤字和中国盟余正在成为全球能源平衡解决方案的组成部分。

关键词：能源市场世界石油大会能源统计 bp公司市场变化年鉴生产特点可再生能源

Compressive behavior and energy absorption of metal porous polymer composite with interpenetrating network structure

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中国有色金属学会会刊：英文版 2006年第B02期16卷 439-443页

作者： LIU Yu GONG Xiao-lu Institut Charles Delaunay CNRS FRE 2848 LASMIS UTT 12 rue Marie Curie BP 2060 10010 Troyes France

Interpenetrating phase composites (IPCs) are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite (MPPC) with an interpenetrating network structure. Aluminum-polypropylene (AI-PE) and Aluminum-epoxy resin (Al-Ep) composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN (H-S) bounds models. The experimental modulus of compressive tests falls well within the theoretical models.

关键词：金属多孔聚合物复合物互穿网络结构压缩行为能量吸收 MPPC复合物

Mild Solutions of a Class of Conformable Fractional Differential Equations with Nonlocal Conditions

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 249-261页

作者： Mohamed BOUAOUID Sultan Moulay Slimane University Faculty of Sciences and TechnicsDepartment of MathematicsBP 52323000Beni MellalMorocco

This paper deals with the existence,uniqueness and continuous dependence of mild solutions for a class of conformable fractional differential equations with nonlocal initial *** results are obtained by means of the cl... 详细信息

关键词： fractional partial differential equations fractional derivatives and integrals cosine family of linear operators nonlocal conditions

Numerical investigation of a latent cold storage system using shell-and-tube unit

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Energy Storage and Saving 2023年第2期2卷 467-477页

作者： Bilal Lamrani Aicha Belcaid Badr Eddine Lebrouhi Tarik El Rhafiki Tarik Kousksou MANAPSE Lab Faculty of SciencesMohammed V University in RabatRabatBP 1014Morocco Faculty of Sciences and Techniques Abdelmalek Essaadi UniversityTangierBP 416Morocco University of Pau and Pays de l’Adour E2SUPPASIAMEPauBP 675-64012France Mohammadia School of Engineering Mohammed V University in RabatRabatBP 765Morocco

The use of cold thermal storage systems in low-temperature industrial applications is considered one of the most promising ways of improving energy efficiency and reducing the use of power during peak *** this study,the thermal performance of a shell-and-tube cold storage system under realistic operating conditions is investigated *** proposed model is developed based on energy balances and then validated using existing experimental data from the ***/water is used as the heat transfer fluid(HTF)and the phase transition phenomena in the phase change material(PCM)is simulated using the enthalpy-porosity *** influence of several design and operating parameters,including the HTF mass flow rate,HTF temperature,PCM type,and volume,on the cold storage performance during the crystallization process is presented and *** numerical results show that increasing the HTF mass flow rate accelerates the PCM crystallization ***,the delivery periods of constant thermal power and constant HTF outlet temperature are *** HTF inlet temperature has a significant effect on the cold storage performance,and the complete charging period is reduced by approximately 37%when the HTF inlet temperature is reduced from−4°C to−7°*** the number of tubes in the cold storage unit is concluded to significantly improve the thermal performance of the system,and using water/ice as a cold storage medium is more suitable than using the commercial PCMs RT2-HC and ***,the proposed numerical model for cold storage systems can be successfully used to design and simulate their realistic operation under different conditions.

关键词： Cold storage Phase change material(PCM) Shell-and-tube unit Crystallization Thermal performance