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国外钻井技术 1994年第5期9卷 44-48页

作者： kenny,p 马旭

A Brief Look into the Lambert W Function

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Applied Mathematics 2013年第6期4卷 887-892页

作者： thomas p. Dence Ashland University Ashland USA

The Lambert W function has its origin traced back 250 years, but it’s just been in the past several decades when some of the real usefulness of the function has been brought to the attention of the scientific community.

关键词： Lagrange Inversion Theorem Infinite Tower of Exponents

Studies on composite solid propellant with tri-modal ammonium perchlorate containing an ultrafine fraction

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Defence Technology（防务技术） 2017年第4期13卷 239-245页

作者： K.V. Suresh Babu p. Kanaka Raju C.R. thomas A. Syed Hamed K.N. Ninan Solid propellant Space Booster plant Satish Dhawan Space Centre Sriharikota 524124 India Rocket propellant plant Vikram Sarabhai Space Centre Thiruvananthapuram 695 022 India Department of Chemistry Indian Institute of Space Science and Technology Thiruvananthapuram 695 547 India

Composite solid propellant is prepared using tri-modal Ammonium perchlorate(Ap)containing coarse,fine and ultrafine fractions of Ap with average particle size(ApS)340,40 and 5 mm respectively,in various compositions and their rheological,mechanical and burn rate characteristics are *** optimum combination of Ap coarse to fine to ultrafine weight fraction was obtained by testing of series of propellant samples by varying the Ap fractions at fixed solid *** concentration of aluminium was maintained constant throughout the experiments for ballistics *** propellant formulation prepared using Ap with coarse to fine to ultrafine ratio of 67:24:9 has lowest viscosity for the propellant paste and highest tensile strength due to dense packing as supported by the literature.A minimum modulus value was also observed at 9 wt.%of ultrafine Ap concentration indicates the maximum solids packing density at this ratio of Ap *** burn rate is evaluated at different pressures to obtain pressure *** of ultrafine fraction of Ap in propellant increased burn rate without adversely affecting the pressure *** solid loading propellants are prepared by increased Ap concentration from 67 to 71 wt.%using Ap with coarse to fine to ultrafine ratio of67:24:*** solid content up to 89 wt.%was achieved and hence increased solid motor *** unloading viscosity showed a trend with increased Ap content and the propellant couldn't able to cast beyond 71 wt.%of *** properties were also studied and from the experiments noticed that%elongation decreased with increased Ap content from 67 to 71 wt.%,whereas tensile strength and modulus *** rate increased with increased Ap content and observed that pressure exponent also increased and it is high for the propellant containing with 71 wt.%of Ap due to increased oxidiser to fuel *** composite solid propellant is prepared by using burn rate modifie

关键词： Ammonium perchlorate Composite propellant Burn rate Copper chromite Iron oxide

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酯基钻井液体系的井眼净化能力

国外钻井技术 1997年第1期12卷 52-58,37页

作者： kenny.,p 田红

System Identification Modeling and Unstable Behavior of the Dynamics of Flows within the Tip Region of an Axial Compressor Blade passage

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Journal of Thermal Science 2016年第2期25卷 109-116页

作者： STERBENTZ Dane M. pRASAI Sujan HOFLE Mary M. WALTERS thomas LIN Feng LI Ji-chao BOSWORTH Ken SCHOEN Marco p. Idaho State University Measurement and Control Engineering Research Center Institute of Engineering Thermophysics Chinese Academy of Sciences

In recent years, the correlation coefficient of pressure data from the same blade passage in an axial compressor unit has been used to characterize the state of flow in the blade passage. In addition, the correlation coefficient has been successfully used as an indicator for active control action using air injection. In this work, the correlation coefficient approach is extended to incorporate system identification algorithms in order to extract a mathematical model of the dynamics of the flows within a blade passage. The dynamics analyzed in this research focus on the flow streams and pressure along the rotor blades as well as on the unsteady tip leakage flow from the rotor tip gaps. The system identification results are used to construct a root locus plot for different flow coefficients, starting far away from stall to near stall conditions. As the compressor moves closer to stall, the poles of the identified models move towards the imaginary axis of the complex plane, indicating an impending instability. System frequency data is captured using the proposed correlation based system identification approach. Additionally, an oscillatory tip leakage flow is observed at a flow coefficient away from stall and how this oscillation changes as the compressor approaches stall is an interesting result of this research. Comparative research is analyzed to determine why the oscillatory flow behavior occurs at a specific sensor location within the tip region of the rotor blade.

关键词： axial compressor correlation coefficient oscillatory behavior system identification

Effect of Sr_(2) TiMnO_(6) fillers on mechanical, dielectric and thermal behaviour of pMMA polymer

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Journal of Advanced Dielectrics 2015年第3期5卷 1-11页

作者： p.thomas B.S.Dakshayini H.S.Kushwaha Rahul Vaish Dielectric Materials Division Central Power Research Institute BangaloreKarnataka 560080India Aerospace Engineering Indian Institute of Science BangaloreKarnataka 560012India School of Engineering Indian Institute of Technology Mandi Himachal Pradesh 175001India

Composites of poly(methyl methacrylate)(pMMA)and Sr_(2) TiMnO_(6)(STMO)were fabricated via melt mixing followed by hot pressing *** were characterized using X-ray diffraction(XRD),thermo gravimetric analysis(TGA),differential scanning calorimetry(DSC),thermo mechanical analysis(TMA)and impedance analyser for their structural,thermal and dielectric *** coefficient of thermal expansion(CTE)was measured between 40℃ and 100℃ for pure pMMA is 115.2ppm/℃,which was decreased to 78.58ppm/℃ when the STMO content was increased to 50 wt.%in *** was no difference in the glass transition(T g)temperature of the pMMA polymer and their ***,the FTIR analysis indicated possible interaction between the pMMA and *** density and the hardness were increased as the STMO content increased in the pMMA *** was found to be as high as 30.9 at 100Hz for the pMMAþSTMO-50 wt.%composites,indicating the possibility of using these materials for capacitor *** thermal stability of polymer was enhanced by incorporation of STMO fillers.

关键词： polymer composite dielectric properties mechanical properties thermal properties

Regular and p-Regular Orbits of Solvable Linear Groups,Ⅱ

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Algebra Colloquium 2023年第2期30卷 301-304页

作者： thomas Michael Keller Yong Yang Department of Mathematics Texas State UniversitySan MarcosTX 78666USA College of Science China Three Gorges University Three Gorges Mathematical Research CenterYichangHubei 443002China Department of MathematicsTexas State UniversitySan MarcosTX 78666USA

Let V be a faithful G-module for a finite group G and let p be a prime dividing IG].An orbit yG for the action of G on V is regular if|v^(G)|=|G:C_(G)(v)]=|G|,and is p-regular if|v^(G)|_(p)=|G:C_(G)(v)|_(p)=|G|_(p).In this note,we study two questions,one by the authors and one by Isaacs,related to the p-regular orbits and regular orbits of the linear group actions.

关键词： regular orbits solvable linear groups group action

Risk factors for musculoskeletal injuries in the military: a qualitative systematic review of the literature from the past two decades and a new prioritizing injury model

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Military Medical Research 2022年第4期9卷 444-483页

作者： Stefan Sammito Vedran Hadzic thomas Karakolis Karen R.Kelly Susan p.proctor Ainars Stepens Graham White Wes O.Zimmermann Section Experimental Aerospace Medicine Research German Air Force Centre of Aerospace MedicineFlughafenstraBe 151147 CologneGermany Occupational Medicine Faculty of MedicineOtto-Von-Guericke-University of Magdeburg39120 MagdeburgGermany Faculty of Sport University of Ljubljana1000 LjubljanaSlovenia Defence Research and Development Canada TorontoON M3K 2C9Canada Warfighter performance Naval Health Research CenterSan DiegoCA 921063599USA Military performance Division US Army Research Institute of Environmental MedicineNatickMA 01760USA Research Service VA Boston Healthcare SystemBostonMA 02130USA Centre for Military Medicine Research Riga Stradins UniversityRiga 1007Latvia Human and Social Sciences Group Defense Science and Technology LaboratoryPortsdown Hill RoadFareham PO176ADUK Department of Military Sports Medicine Royal Netherlands Army3584 AB UtrechtThe Netherlands Department of Military/Emergency Medicine Uniformed Services University of the Health SciencesBethesdaMD 20814USA.

Background: Musculoskeletal injuries(MSkIs) are a leading cause of health care utilization, as well as limited duty and disability in the US military and other armed forces. MSkIs affect members of the military during initial training,operational training, and deployment and have a direct negative impact on overall troop readiness. Currently, a systematic overview of all risk factors for MSkIs in the military is not ***: A systematic literature search was carried out using the pubMed, Ovid/Medline, and Web of Science databases from January 1, 2000 to September 10, 2019. Additionally, a reference list scan was performed(using the “snowball method”). Thereafter, an international, multidisciplinary expert panel scored the level of evidence per risk factor, and a classification of modifiable/non-modifiable was ***: In total, 176 original papers and 3 meta-analyses were included in the review. A list of 57 reported potential risk factors was formed. For 21 risk factors, the level of evidence was considered moderate or strong. Based on this literature review and an in-depth analysis, the expert panel developed a model to display the most relevant risk factors identified, introducing the idea of the “order of importance” and including concepts that are modifiable/nonmodifiable, as well as extrinsic/intrinsic risk ***: This is the qualitative systematic review of studies on risk factors for MSkIs in the military that has attempted to be all-inclusive. A total of 57 different potential risk factors were identified, and a new, prioritizing injury model was developed. This model may help us to understand risk factors that can be addressed, and in which order they should be prioritized when planning intervention strategies within military groups.

关键词： Military Musculoskeletal injuries Risk factors prevention Intervention Injury

26mA cm^(-2) J_(sc) from organic solar cells with a low-bandgap nonfullerene acceptor

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Science Bulletin 2017年第22期62卷 1494-1496页

作者： Zuo Xiao Xue Jia Dan Li Shizhe Wang Xinjian Geng Feng Liu Junwu Chen Shangfeng Yang thomas p.Russell Liming Ding Center for Excellence in Nanoscience (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication (CAS)National Center for Nanoscience and Technology Department of Materials Science and Engineering University of Science and Technology of China Department of physics and Astronomy Shanghai Jiaotong University State Key Laboratory of Luminescent Materials and Devices South China University of Technology Department of polymer Science and Engineering University of Massachusetts

Nonfullerene-based organic solar cells(NFOSCs)have received great interest recently due to their higher performance and greater potential compared with fullerene-based solar cells[1].power conversion efficiencies(pCEs)over 13% have been realized in single-junction NFOSCs[2].Compared with traditional fullerene acceptors,the greatest advantage of nonfullerene acceptors is their stronger light-harvesting capability in the visible and

关键词： pTB Th sc from organic solar cells with a low-bandgap nonfullerene acceptor DIO pCE

Lessons from the past:isotopes of an endangered rail as indicators of underlying change to tidal marsh habitats

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Ecosystem Health and Sustainability 2017年第11期3卷 15-30页

作者： Angela M Merritt Michael L Casazza Cory T Overton John Y Takekawa thomas p Hahn Joshua M Hull u.s.geological survey western ecological research center dixon field office dixoncausa department of animal science university of california davisdaviscausa

Introduction:Tidal marsh systems along the pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function,which we examined by using the endangered California Ridgway’s Rail,Rallus obsoletus obsoletus(‘rail’)as an indicator of its tidal marsh habitat in the San Francisco *** organized a collection of historical(1885-1940)and modern(2005-2014)rail feathers and analyzed the feather isotope means for delta carbon(δ^(13)C),sulfur(δ^(34)S),and nitrogen(δ^(15)N)by region and time ***:Feather isotopes represented the primary foraging habitat during historical then modern time *** individual nor regional rail feather isotopes suggested freshwater or terrestrial foraging by the *** regions with both historic and modern feather isotopes revealed non-uniform spatial shifts in isotope levels consistent with a marine based food web and significantδ^(15)N ***:Our results supported the rail’s status as a generalist forager and obligate tidal marsh species throughout the historic *** variable isoscape trends generated from feather isotope means illustrated a modern loss of the isotopic homogeneity between regions of historical tidal marsh,which correlated with spatially-explicit habitat alterations such as increasing biological invasions and sewage effluent over ***:These findings have reinforced the importance of tidal marsh conservation in the face of ongoing underlying changes to these important ecosystems.

关键词： Historical change estuary food webs isoscapes isotopes Ridgway’s rail tidal marsh