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Energy and blast performance of beryllium in a model thermobaric composition in comparison with aluminum and magnesium

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Defence Technology（防务技术） 2024年第6期36卷 13-19页

作者： Thomas M.Klapotke stanisław Cudziło Waldemar A.Trzcinski Jozef Paszula Energetic Materials Research Department of ChemistryUniversity of Munich(LMU)Butenandtstrasse 5-13(D)81377MunichGermany Military University of Technology Faculty of Advanced Technologies and ChemistrySylwester Kaliski Str.200-908WarsawPoland

A direct comparison is made between the effectiveness of Al,Mg,and Be powders as additional fuels in model thermobaric compositions containing 20%fuel,20%ammonium perchlorate,and 60%RDX(1,3,5-Trinitro-1,3,5-triazacyclohexane)passivated with *** determined calorimetric measurements of the heat of detonation,along with the overpressure histories in an explosion chamber filled with nitrogen,were used to determine the quasi-static pressure(QSP)under anaerobic *** measurements were also performed in a semi-closed bunker,and all blast wave parameters generated after the detonation of 500 g charges of the tested explosives were *** calorimetry results,QSP values,and blast wave parameters(pressure amplitude,specific and total impulses)clearly indicate that Be is much more effective as an additional fuel than either Al or Mg in both anaerobic post-detonation reactions as well as the subsequent aerobic *** heat of detonation of the RDXwax/AP/Be explosive mixture is over 40%and 50%higher than that of the mixture containing aluminum and magnesium instead of beryllium,***,the TNT equivalent of the Be-containing composition due to the overpressure in the nitrogen-filled explosion chamber is 1.66,while the equivalent calculated using an air shock wave-specific impulse at a distance of 2.5 m is equal to *** high values of these parameters confirm the high reactivity of beryllium in both the anaerobic and aerobic stages of the thermobaric explosion.

关键词： Thermobaric explosives Beryllium Heat of detonation Quasi-static overpressure Blast wave parameters

The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests

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Forest Ecosystems 2024年第3期11卷 339-346页

作者： Ewa Błonska Adam Gorski Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

Decaying wood is an essential element of forest ecosystems and it affects its other *** aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest *** research was carried out in the Babiog orski National *** research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle *** plots were located in undisturbed *** research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 *** samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was *** characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture *** decomposition of wood in the gaps regardless of the species is related to lower *** wood species covered by the study differed in the decomposition *** wood samples were characterized by a significantly higher decomposition rate compared to beech wood *** research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.

关键词： Bark beetle Beech Decomposition rate Forest ecosystem Mass decline Spruce Woody debris

Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 131-140页

作者： Zhongyang Wang Youqing Wang Zdzisław Kowalczuk the College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China IEEE the Department of Robotics and Decision Systems Faculty of ElectronicsTelecommunications and InformaticsGdańsk University of TechnologyGdansk 80-233Poland

In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection.

关键词： Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)

Bone graft incorporation failure with inappropriate limb load transfer can lead to aseptic acetabular loosening of metal-on-metal prosthesis: A case report

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World Journal of Orthopedics 2024年第7期15卷 668-674页

作者： Rafałstanisław Domagalski Bogdan Dugiełło Sonia Rokicka Szymon Czech RafałSkowroński Dominika Rokicka Marta Patrycja Wróbel Krzysztof Strojek Tomasz Stołtny District Hospital of Orthopaedics and Trauma Surgery in PiekaryŚląskie PiekaryŚląskie 41-940Poland District Railway Hospital Medical University of SilesiaKatowice 40-760Poland Faculty of Medicine Medical University of GdańskGdańsk 80-210Poland “ALFA”Orthopaedics and Traumatology Center Białystok 15-763Poland Department of Internal Medicine Diabetology and Cardiometabolic DisordersFaculty of Medical Sciences ZabrzeMedical University of SilesiaZabrze 41-800Poland

BACKGROUND Aseptic acetabular loosening can result from various factors that can be categorized into groups:patient-related,surgeon-related and *** present a case of a 63-year-old patient who at first underwent a total hip arthro-plasty(THA)using a metal-on-metal bearing due to hip ***-up visits revealed no complications after the *** years after the THA,acetabular component loosening occurred due to subsequent trauma of the opposite hip,necessitating a revision THA using a ceramic-on-ceramic *** SUMMARY We aim to illustrate a rare case where the primary reason for undergoing THA revision was not only incomplete bone graft incorporation but also improper limb load *** the revision arthroplasty,a 9-year follow-up visit revealed improvements in all evaluation measures on questionnaire compared to the state before surgery:Harris Hip Score(before surgery:15;after surgery:95),Western Ontario and McMaster Universities Arthritis Index(before surgery:96;after surgery:0),and Visual Analogue Scale(before surgery:10;after surgery:1).CONCLUSION Opposite-hip trauma caused a weight transfer to the limb after a THA *** process led to a stress shielding effect,resulting in acetabular component loosening.

关键词： Acetabular loosening Limb load Stress shielding effect Revision hip arthroplasty Case report

Flat-footed Females and Missing Males:A New Genus and Species of Pleciofungivoridae(Diptera:Bibionomorpha)Represents the First Record of the Family from Mid-Cretaceous Kachin Amber

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 541-547页

作者： ZHANG Qingqing Wiesław KRZEMINSKI Jan SEVCIK Vladimir BLAGODEROV Agnieszka SOSZYNSKA Kornelia SKIBINSKA Yunnan Key Laboratory for Palaeobiology Institute of PalaeontologyYunnan UniversityKunming 650500China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment Yunnan UniversityKunming 650500China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Institute of Systematics and Evolution of Animals Polish Academy of Sciences52551 KrakówPoland University of Ostrava Faculty of ScienceDepartment of Biology and EcologyChittussiho 10CZ-71000 OstravaCzech Republic National Museums Scotland EdinburghUK Natural History Museum LondonUK University of Lodz Faculty of Biology and Environmental ProtectionDepartment of Invertebrate Zoology and HydrobiologyBanacha 12/1690-237ŁódźPoland

A new genus and species,Cretopleciofungivora simpsoni *** ***.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin ***,this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower *** of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper *** new species has a unique structure of fore tarsus,with lobed and extended tarsal segments Ⅱ to Ⅳ,a feature hitherto known only in a few species of extant *** not particularly rare,the new species is currently known only from female *** reasons for this phenomenon,very unusual in Sciaroidea,are briefly discussed,including parthenogenesis as a potentially plausible hypothesis.

关键词： fungus gnats Sciaroidea Upper Cretaceous Burmese amber swollen tarsomeres

Initial colonisation by Rhizocarpon geographicum in the Tatra Mountains

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Journal of Mountain Science 2021年第2期18卷 407-415页

作者： stanisław KĘDZIA Department of Geoenvironmental Research Institute of Geography and Spatial OrganizationPolish Academy of SciencesCracow 31-018ul.św.Jana 22Poland

Previous lichenometric dating of young geomorphological forms in the Tatra Mountains has been hindered by differences in the determination of initial colonisation of fresh rock surfaces by the Rhizocarpon geographicum *** order to determine precisely the time needed for the first thalli to appear on newly exposed rock surfaces,two experimental sites were created in *** results from these sites were compared with the measurements taken on boulders in debris formed by a 2013 debris *** 2018,the largest thalli measured within the experimental sites and the debris flow area reached a size of approximately 2 *** on this,the time of initial colonisation of rock surfaces was determined to be 5±1 years,which is about half the period previously described in the literature.

关键词： Lichenometric dating Rhizocarpon geographicum Initial colonisation Geomorphological forms Tatra Mts

Synthesis and properties of novel nitro-based thermally stable energetic compounds

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Defence Technology（防务技术） 2021年第3期17卷 775-784页

作者： Łukasz Gutowski stanisław Cudziło Military University of Technology Faculty of Advanced Technologies and ChemistryGen.Sylwestra Kaliskiego 2 Street00-908WarsawPoland

This paper reviews the achievements in the field of synthesis of new thermally resistant explosive compounds in the years 2009 through 2019. The performance characteristics of these compounds(sensitivity, thermal decomposition parameters, and detonation parameters) were compared with those of 1,3,5-triamino-2,4,6-trinitrobenzene, which still seems to be an unrivalled model of a thermally resistant and generally low-sensitivity explosive material. New thermally stable explosives(TSEs) were found among macromolecular compounds with tri-and dinitrophenyl groups, nitro and amine-nitro derivatives of azoles, and polynitro derivatives of calixarenes. Some of them match TATB in terms of thermal resistance and additionally have higher detonation parameters.

关键词： Heat resistant explosives Detonation parameters Synthesis Nitration

Influence of canopy ratio of powered roof support on longwall working stability——A case study

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International Journal of Mining Science and Technology 2019年第4期29卷 591-598页

作者： Sylwester Rajwa Tomasz Janoszek stanis?aw Prusek Department of Extraction Technologies Rockburst and Mining Support Central Mining Institute

The case study describes longwall coal seam A in a hard coal mine,where longwall coal face stability loss and periodic roof fall occurrences had been *** authors have attempted to explain the situation based on in-situ measurements and observations of the longwall working as well as numerical *** calculations included several parameters,such as powered roof support geometry in the form of the canopy ratio,which is a factor that influences load distribution along the *** simulations were realized based on a rock mass model representing realistic mining and geological conditions at a depth of 600 m below surface for coal seam *** model assumptions are described,while the obtained results were compared with the in-situ *** conclusions drawn from this work can complement engineering knowledge utilized at the stage of powered roof support construction and selection in order to improve both personnel safety and longwall working stability,and to achieve better extraction.

关键词： Coal mining Modelling Powered roof supports Longwall workings Safety Stability

Simplified Numerical Study of Evaporation Processes Inside Vertical Tubes

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Journal of Thermal Science 2014年第2期23卷 177-186页

作者： Pawe Ocoń Marzena Nowak stanisaw Lopata Cracow University of Technology Faculty of Mechanical EngineeringInstitute of Thermal Power EngineeringAl.Jana PawaII 3731-864 CracowPoland

The paper presents a simplified numerical model of evaporation processes inside vertical *** this model only the temperature fields in the fluid domain(the liquid or two-phase mixture) and solid domain(a tube wall) are *** its performance and efficiency is *** analytical formulas,which allow calculating the pressure drop and the distribution of heat transfer coefficient along the tube length,are used in this *** energy equation for the fluid domain is solved with the Control Volume Method and for the solid domain with the Finite Element Method in order to determine the temperature field for the fluid and solid domains.

关键词： Numerical modeling heat transfer evaporation vertical tubes Finite Element Method