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Defence Technology（防务技术） 2024年第4期34卷 11-18页

作者： Jacky cailes robert Dunsmore Kathryn L.Linge chemcentre PO Box 1250PerthAustralia

The Marplex convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of ***,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the *** this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within *** both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB *** all three plastic explosives tested,the concentration of DMDNB was measured by SPME-Gc-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex *** testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the ***,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for *** is likely that similar results would be found for other taggants stipulated by the Marplex convention,given they are also present in concentrations less than 1%.

关键词： Explosive IcAO taggants 2,3-Dimethyl-2,3-dinitrobutane(DMDNB) Fourier transform infrared(FTIR) Raman

Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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Particuology 2024年第6期89卷 258-269页

作者： Martin Oelofse robert Rack Marcelle Hilden Peter Langguth Department of Pharmaceutical Technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle *** study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production *** in a second production step carbon tablets with a high porosity were molded for the customer goods *** optimization of the compressive strength of these carbon tablets was the goal of the *** agglomerates were produced with a laboratory scale granulator called“Procell”and were compressed with a five-cavity mechanical *** screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial *** experimental runs were done by varying atomized air pressure and feed rate of the *** was determined by the design *** findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments carbon agglomerates and tablets

The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： Samuel BOND robert L.JAcKSON German MILLS Department of chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

Leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact *** findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)*** rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without *** forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(SEM)including compositional analysis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current

Seismic attribute and well-log analysis for channel characterization in the upper San Andres and Grayburg formations of the Midland Basin,Texas

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 263-278页

作者： Sumit Verma Esra Yalçın Yılmaz Laura Ortiz Sanguino Justin Yandell Miles A.Henderson robert c.Trentham Department of Geosciences The University of Texas Permian BasinOdessaTXUSA School of Geosciences The University of OklahomaNormanOKUSA

The Permian Basin is one of the most prolific,and currently one of the most active,oil and gas basins in the *** lower Permian strata in the Permian Basin have produced more than 14 billion barrels of oil(BBO),making it the largest volume of hydrocarbon in the *** in the Midland Basin during late Leonardian through early Guadalupian(ca.272-269 Ma)resulted in progradation of shelf edge and ultimately closure of the basin by Middle Permian *** analyzed a merged seismic survey covering parts of the Permian Basin(i.e.,central Basin Platform and Midland Basin)in Andrews,Ector,and Midland counties,*** seismic survey and well logs show the presence of gently dipping(ca.1°)clinoforms in the Upper San Andres and Grayburg Formations on the eastern edge of the central Basin Platform and western Midland *** seismic attributes,curvature,and spectral decomposition identify low sinuosity slope channels oriented north-south,but such channels do not appear beyond the *** shelf edge shifts from north to south during deposition of the Upper San Andres and Grayburg *** identify five basinward shifts noted by the migration of the shelf edge toward the basin center and the presence of channel features along the depositional *** petrophysical analysis indicates that channels cut into carbonate rocks and are filled by siliciclastic sediments;this interpretation is supported by the most negative curvature anomalies along the channel axes caused by the differential compaction between the carbonate and siliciclastic *** are a few channels with a northwest-southeast strike,which matches the direction of the concho Lineament observed by satellite *** observations are consistent with previous interpretations of the northern Midland Basin closure during Middle-Late Permian time.

关键词： Permian shelf carbonate

Potential of contemporary earth-sheltered buildings to achieve Plus Energy status in various European climates during the heating season

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Building Simulation 2024年第1期17卷 41-52页

作者： Aleksandar Nesovic Nebojsa Jurisevic robert Kowalik lvana Terzic Faculty of Engineering University of KragujevacSestre Janjic 634000 KragujevacSerbia Faculty of Environmental Geomatic and Energy EngineeringKielce University of TechnologyTysigclecia Panstwa Polskiego725-314 KielcePoland

This study investigates the potential of contemporary Earth-Sheltered Buildings to contribute to sustainable societies by achieving Plus Energy Building status during the heating *** buildings analyzed are intended to house a four-member family(102.5 m^(2)).The house is equipped with a ground source heat pump,geothermal vertical probes,floor heating panels,an energy recovery ventilator,and building-integrated photovoltaic panels installed on the exposed building *** numerical analysis(using EnergyPlus software)was carried out for nine European sites covering five different climatic zones(namely:southern,Atlantic,continental,alpine,and northern climate)and three latitude belts spanning Europe from south to *** above 65°N(northern and alpine climate)could not achieve Plus Energy status with 20% efficient *** 15% efficient BIPVs,the building above 59°N(northern climate)was incapable of achieving this as *** the monthly time step,the buildings in the southern and Atlantic climates with 15% efficient BiPVs were able to produce an energy surplus every month,as was the building in theAlps with 20% efficientBIPVs.

关键词： civil engineering earth-sheltered buildings renewable energy sustainable societies Plus Energy Buildings Energy Plus software

Effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease:clinical implications

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World Journal of Gastroenterology 2024年第27期30卷 3264-3267页

作者： Giovanna McGinty robert Przemioslo Department of Gastroenterology North Bristol TrustSouthmead HospitalBristol BS105NBUnited Kingdom Department of Gastroenterology and Hepatology North Bristol TrustSouthmead HospitalBristol BS105NBUnited Kingdom

In this editorial,we comment on the article by chen et al recently published in *** focus the debate on whether reducing the upper limit of normal of alanine aminotransferase(ALT)would effectively identify cases of fibrosis in metabolic-dysfunction associated fatty liver disease(MAFLD).This is important given the increasing prevalence of MAFLD and obesity ***,a suitable screening test to identify patients in the general population does not exist and most patients are screened after the finding of an abnormal *** authors of this paper challenge the idea of what a normal ALT is and whether that threshold should be lowered,particularly as their study found that 83.12%of their study population with a diagnosis of MAFLD had a normal *** main advantages of screening would be to identify patients and provide intervention early,the mainstay of this being changing modifiable risk factors and monitoring for liver ***,there is not enough suitable therapeutic options available as of yet although this is likely to change in the coming years with more targets for therapy being *** is one example of this which has demonstrated benefit with an acceptable side effect profile for those patients with MAFLD and obesity,although studies have not yet shown a significant improvement in fibrosis *** would also require a huge amount of resource if a reduced ALT level alone was used as criteria;it is more likely that current scoring systems such as fibrosis-4 may be amended to represent this additional ***,there is not a good argument to recommend wide-spread screening with a reduced ALT level as this is unlikely to be *** is compounded by the fact that there is a significant heterogeneity in what is considered a normal ALT between *** studies previously have suggested a more pragmatic approach in screening those over the age of 60,this is likely to change with the increasing inc

关键词： Alanine aminotransferase Metabolic-dysfunction associated fatty liver disease Metabolic syndrome Fibrosis cirrhosis Semaglutide

Glycolysis and glucose metabolism as a target for bioenergetic and neuronal protection in glaucoma

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Neural Regeneration Research 2024年第8期19卷 1637-1638页

作者： Pete A.Williams robert J.casson Department of clinical Neuroscience Division of Eye and VisionSt.Erik Eye HospitalKarolinska InstitutetStockholmSweden Ophthalmic Research Laboratories Discipline of Ophthalmology and Visual SciencesUniversity of AdelaideAdelaideAustralia

Vision is arguably our most valued sense,yet approximately 340 million people globally suffer blindness or moderate visual impairment,highlighting the need to further develop and advance treatments for ophthalmic *** refers to a group of ocular disorders united by a clinically characteristic optic neuropathy with associated retinal ganglion cell loss.

关键词： metabolism glaucoma globally

Science and reflections: With some thoughts to young applied scientists and engineers

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Earthquake Science 2024年第5期37卷 459-493页

作者： robert L Nowack Department of Earth Atmospheric and Planetary SciencesPurdue UniversityWest LafayetteIN47906USA

I provide some science and reflections from my experiences working in geophysics,along with connections to computational and data sciences,including recent developments in machine learning.I highlight several individuals and groups who have influenced me,both through direct collaborations as well as from ideas and insights that I have learned *** my reflections are rooted in geophysics,they should also be relevant to other computational scientific and engineering fields.I also provide some thoughts for young,applied scientists and engineers.

关键词： geophysics computational and data science applied science and engineering

Utility and Application of a Versatile Analytical Method for MMF calculation in Ac Machines

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cES Transactions on Electrical Machines and Systems 2024年第1期8卷 22-31页

作者： Ze-Zheng Wu robert Nilssen Jian-Xin Shen IEEE the college of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Department of Electric Energy Norwegian University of Science and TechnologyTrondheimNorwayand also affiliated with the College of Electrical EngineeringZhejiang UniversityHangzhou 310027China

A versatile analytical method(VAM) for calculating the harmonic components of the magnetomotive force(MMF) generated by diverse armature windings in Ac machines has been proposed, and the versatility of this method has been established in early literature. However, its practical applications and significance in advancing the analysis of Ac machines need further elaboration. This paper aims to complement VAM by augmenting its theory, offering additional insights into its conclusions, as well as demonstrating its utility in assessing armature windings and its application of calculating torque for permanent magnet synchronous machines(PMSM). This work contributes to advancing the analysis of Ac machines and underscores the potential for improved design and performance optimization.

关键词： Ac machine Analytical method Harmonic analysis MMF Magnetic field Torque calculation

coupled Inversion of Pressure and Tiltmeter Data for Mapping Hydraulic Fracture Geometry

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Acta Mechanica Solida Sinica 2024年第3期37卷 396-405页

作者： Zuorong chen Xiaofang Jiang Zhejun Pan robert G.Jeffrey National Key Laboratory of continental Shale Oil Northeast Petroleum UniversityDaqing163318China ScT Operation Pty.Ltd. PO Box 824WollongongNSW2520Australia

Pressure and tilt data are jointly inverted to simultaneously map the orientation and dimensions of a hydraulic *** deformation induced by a fracture under internal pressure is modeled using the distributed dislocation *** planar fracture is represented by four quarter ellipses,joined at the center and sharing *** configuration provides a straightforward model for characterizing asymmetric fracture *** inverse problem of mapping the fracture geometry is formulated using the Bayesian probabilistic method,combining the a priori information on the fracture model with updated information from pressure and tilt *** the nonlinear inverse problem is achieved by pseudo-randomly sampling the posterior probability distribution through the Markov chain Monte carlo *** resulting posterior probability distribution is then explored to assess uncertainty,resolution,and correlation between model *** experiments are conducted to verify the accuracy and validity of the proposed analysis method in mapping the fracture geometry using synthetic pressure and tilt data.

关键词： Hydraulic fracture mapping coupled inversion Tilt Treating pressure