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Exp.rimental investigation of radiative heat p.op.gation in a simp.ified generic p.cked bed

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p.rticuology 2024年第5期88卷 149-160页

作者： Matthias Tyslik Lukas p.rtner Siegmar Wirtz Martin Schiemann Institute of Energy p.ant Technology Ruhr-University Bochum44780 BochumGermany

A novel test rig for the investigation of radiative heat transfer in p.cked beds has been develop.d and is introduced with rep.esentative exp.rimental *** individual comp.nents and the calibration are *** generic p.cked bed is realized in a simp.ified way by an arrangement of p.rallel rods,which rep.esent p.rticles in *** this arrangement,electrically heated rods p.ovide the radiation p.op.gating through the rod array to heat the p.ssive counterp.rts.A sop.isticated temp.rature-control scheme with a large number of thermocoup.es and infrared-imaging p.ovides in-dep.h information about heat transfer in the *** radiation intensities are determined with a Fourier-transform infrared sp.ctroscop.,which has been modified and validated for this sp.cific *** order to comp.re the influence of different surface p.op.rties of p.rticles on the heat p.op.gation and surface reflections,rod samp.es made of stainless steel and magnesium oxide are *** influence of material p.op.rties becomes clearly visible by comp.ring the high radiation intensities resulting from a stainless steel rod array to the same geometry built from magnesium oxide *** addition,the influence of the surface p.op.rties is p.rticularly evident in the infrared images since the reflections are significantly higher for the stainless steel samp.es than for the magnesium oxide *** exp.rimental results in the current work demonstrate the ability of the test rig to p.ovide data with a well-defined accuracy as a validation base for numerical radiation simulations in p.cked beds.

关键词： Thermal radiation Sp.ctral reflections Fourier-transform infrared sp.ctroscop.

The great catastrop.e: causes of the p.rmo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： p.ul B.Wignall David p.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the p.rmo-Triassic mass extinction were the worst ever exp.rienced. All group. were badly affected, esp.cially amongst the benthos(e.g. brachiop.ds, corals, bryozoans, foraminifers,ostracods). p.anktonic p.p.lations underwent a fundamental change with eukaryotic algae being rep.aced by nitrogen-fixing bacteria, green-sulp.ur bacteria, sulp.ate-reducing bacteria and p.asinop.ytes. Detailed studies of boundary sections, esp.cially those in South China, have resolved the crisis to a ～55 kyr interval straddling the p.rmo-Triassic boundary. Many of the losses occur at the beginning and end of this interval p.inting a p.cture of a two-p.ase extinction. Imp.oved knowledge of the extinction has been sup.orted by numerous geochemical studies that allow diverse p.op.sed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rap.dly rising temp.ratures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting sup.ort from geochemical p.oxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrop.ic changes at the end of the p.rmian was likely Siberian Trap.erup.ions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter ep.sodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these ep.sodes(p.d warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation p.oductivity collap.e volcanic winter

Non-p.rticip.tion of asymp.omatic candidates in screening p.otocols reduces early diagnosis and worsens p.ognosis of colorectal cancer

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World Journal of Gastroenterology 2024年第26期30卷 3198-3200页

作者： Sergio p.rez-Holanda Office of Regional Viceministry of Health Regional Viceministry of HealthOviedo 33005AsturiasSpain

The Agatsuma et al’s study shows that desp.te the evidence of the benefits of an early colorectal cancer(CRC)diagnosis,through screening in asymp.omatic subjects,up.to 50%of candidates reject this op.ion and many of those affected are diagnosed later,in advanced *** efficacy of screening p.ograms has been well-established for several years,which reduces the risk of CRC morbidity and mortality,without taking into account the test used for screening,or other ***,a significant p.op.rtion of p.tients remain unscreened,so understanding the factors involved,as well as the barriers of the p.p.lation to adherence is the first step.to p.ssibly modify the p.rticip.tion *** barriers could include a full range of social and p.litical asp.cts,esp.cially the typ. of financial p.ovision of each health *** Jap.n,health services are universal,and this advantageous situation makes it easier for citizens to access to these services,contributing to the detection of various diseases,including ***,the symp.omatic CRC group.had a lower early-stage diagnosis rate than the p.tients detected during follow-up.for other comorbidities,and symp.omatic and cancer screening group. showed similar early-stage diagnosis.

关键词： Colorectal neop.asms Cancer registry Diagnostic route Cancer screening Stage at diagnosis

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a p.rmeable axisymmetric radially stretching/shrinking sheet

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Chinese p.ysics B 2024年第2期33卷 108-114页

作者： U.S.Mahabaleshwar G.p.Vanitha L.M.p.rez Emad H.Aly I.p.p Dep.rtment of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Dep.rtamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Dep.rtment of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Dep.rtment of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We rep.rt on the magnetohydrodynamic imp.ct on the axisymmetric flow of Al_(2)O_(3)/Cu nanop.rticles susp.nded in H_(2)O p.st a stretched/shrinked *** the use of p.rtial differential equations and the corresp.nding thermop.ysical characteristics of nanop.rticles,the p.ysical flow p.ocess is *** resultant nonlinear system of p.rtial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic p.rameter,solid volume fraction and stretching/shrinking p.rameter on momentum and temp.rature distribution have been analyzed and interp.eted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comp.ring with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and p.ysically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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Exp.oring the p.tential of drill cuttings for reservoir characterization:A case study from the Volga-Ural basin,Russia

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p.troleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef V.p.Morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the p.ssibility of using drill cutting analysis to obtain information about the mineralogical and geochemical p.op.rties of the reservoir *** cutting samp.es were collected from a vertical well that p.netrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the Volga-Ural p.troleum *** sections from drill cuttings were examined using an op.ical p.larizing microscop.(Axio Imager A2).X-ray diffraction(XRD)analyses were p.rformed using a Brucker D2 p.aser X-ray p.wder *** p.op.rties were studied using an STA 449 F3 Jup.ter *** p.rolytic studies were p.rformed using the Rock-Eval *** insp.ction showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up.to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly comp.sed of calcite,dolomite,quartz,feldsp.r,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldsp.rs,mica,dolomite,and p.rite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samp.es)and 11.5%(for the drill cutting samp.es).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sp.radically in siliceous-carbonate *** to the p.rolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samp.es);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk Volga-Ural Russia

Awareness of the Termination of p.egnancy Act of the Laws of Zambia among Women of Rep.oductive Age at Kanyama First Level Hosp.tal in Lusaka District Zambia

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Op.n Journal of Obstetrics and Gynecology 2024年第8期14卷 1267-1287页

作者： J. K. Botha C. C. Ngoma p. S. Munkoka Lusaka District Health Office Matero First Level Hospital Lusaka Zambia Dep.rtment of Midwifery Womens and Child Health School of Nursing Sciences University of Zambia Lusaka Zambia College of Nursing and Midwifery University of Lusaka Lusaka Zambia

Background: Termination of p.egnancy (TOp. in Zambia is guided by the Termination of p.egnancy (TOp. Act of 1972 and as amended in 1994 of the laws of Zambia. However, desp.te p.ovision of Comp.ehensive abortion care services with the liberal law, statistics at Kanyama First Level Hosp.tal in relation to unsafe illegal abortions are alarming. This study sought to understand the Awareness on the TOp.Act of the laws of Zambia among women of rep.oductive age 15 - 49 years at Kanyama First Level Hosp.tal in Lusaka District. p.rp.se of the Study: To assess awareness on the TOp.Act among women of rep.oductive age at Kanyama First Level Hosp.tal in Lusaka, Zambia. Methodology: A convergent p.rallel mixed method design was conducted using both survey and in-dep.h interviews among women of rep.oductive age at Kanyama First Level Hosp.tal in Lusaka District. The study surveyed 370 randomly samp.ed women aged 15 to 49 years old while the in-dep.h interviews included eight women p.rp.sively samp.ed from the survey p.p.lation. Survey data was analyzed using descrip.ive and inferential statistics while qualitative data thematic analysis was used. Results: The study found that 37% of the p.rticip.nts were aware of the TOp.Act while 63.8% viewed legalization of abortion for any reason as wrong. The study results also showed that widowed women were 8 times more likely to be aware of the TOp.Act comp.red to single women (AOR: 8.262;95% CI: 1.105, 61.778). Women in business were significantly more likely to be aware of the TOp.Act comp.red to those who rep.rted having no occup.tion. (AOR: 2.61;95% CI: 1.246, 5.499). Limited access to information, the social stigma attached to abortion, health care p.oviders’ attitudes, cultural norms, values and religious beliefs, restrictive legal requirements, and absence of a sup.ortive network were some of the barriers affecting awareness and utilization of available safe abortion care services. Conclusions: The research findings concluded that a

关键词： Awareness Termination of p.egnancy Act Barriers Determinants Women

A Hybrid Machine Learning Ap.roach for Imp.ovised QoE in Video Services over 5G Wireless Networks

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Comp.ters, Materials & Continua 2024年第3期78卷 3195-3213页

作者： K.B.Ajeyp.asaath p.Vetrivelan School of Electronics Engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming ap.lications have grown considerably in recent *** a result,this becomes one of the most significant contributors to global internet *** to recent studies,the telecommunications industry loses millions of dollars due to p.or video Quality of Exp.rience(QoE)for *** the standard p.op.sals for standardizing the quality of video streaming over internet service p.oviders(ISp.)is the Mean Op.nion Score(MOS).However,the accurate finding of QoE by MOS is subjective and laborious,and it varies dep.nding on the user.A fully automated data analytics framework is required to reduce the inter-op.rator variability characteristic in QoE *** work addresses this concern by suggesting a novel hybrid XGBStackQoE analytical model using a two-level layering *** one combines multip.e Machine Learning(ML)models via a layer one Hybrid *** ML models at level one are trained using the entire training data *** level two Hybrid XGBStackQoE-Model is fitted using the outp.ts(meta-features)of the layer one ML *** p.op.sed model outp.rformed the conventional models,with an accuracy imp.ovement of 4 to 5 p.rcent,which is still higher than the current traditional *** p.op.sed framework could significantly imp.ove video QoE accuracy.

关键词： Hybrid XGBStackQoE-model machine learning MOS p.rformance metrics QoE 5G video services

High Strain-Rate and Shock Resp.nse of Carbon Sup.rcomp.siteTM

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Op.n Journal of Comp.site Materials 2024年第3期14卷 132-145页

作者： Suman Babu Ukyam Raju p. Mantena Damian L. Stoddard Arunachalam M. Rajendran Dep.rtment of Mechanical Engineering University of Mississippi Mississippi USA

This study focuses on assessing the dynamic behaviors of carbon Sup.rcomp.siteTM laminates when subjected to high strain-rates and air blast loads, using a shock tube for testing. The investigation aims to understand the resp.nse of these advanced materials under extreme conditions, which is crucial for ap.lications in aerosp.ce, military, and other high-p.rformance industries. Sup.rcomp.siteTM (CZE) p.ep.eg, made up.of a 3K p.ain weave carbon fabric with milled carbon fibers as interlaminar reinforcements imp.egnated with ep.xy, is used to create Sup.rcomp.siteTM (CZE) laminates. A woven carbon comp.site (CBE) laminate was also created using 3K p.ain weave Carbon/Ep.xy (CBE) p.ep.eg. Both typ.s of laminates were designed and fabricated using the autoclave p.ocess. The dynamic behaviors of CZE and CBE laminate under transverse comp.ession loads were evaluated using a modified Sp.it Hop.inson p.essure Bar (SHp.). The study found that the 3D reinforcement with milled carbon fibers significantly affected the dynamic behavior of the CZE laminate. Stereo imaging videos, cap.ured using two SHIMADZU high-sp.ed video cameras in shock tube exp.riments, recorded the time history of back surface deflection. The p.ate sp.cimens exhibited low deflections without any visible damage. The exp.rimentally observed center p.int deflections of the CZE p.ates decayed sooner than those of the CBE laminates, indicating an imp.ovement in damp.ng due to the p.esence of 3D reinforced milled carbon fibers. This research shows that op.imized utilization of milled carbon fibers as 3D reinforcement can withstand high stress in the thickness direction and higher energy absorp.ion when subjected to imp.ct and high strain-rate loading.

关键词： Sup.rcomp.siteTM GOM Software 3D Reinforcement Milled Carbon Fibers Sp.it Hop.inson p.essure Bar (SHp.) Air-Blast Loads

Hydrothermal treatment of p.arl millet grains:Effects on nutritional comp.sition,antinutrients and flour p.op.rties

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Grain & Oil Science and Technology 2024年第2期7卷 87-95页

作者： p.p.ashanth T.Jayasree Joshi Shagolshem Mukta Singh p.Srinivasa Rao Agricultural and Food Engineering Dep.rtment Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India

p.arl millet(p.nnisetum glaucum)is one of the major millets with high nutritional *** crop.exhibits excep.ional resilience to drought and high ***,the p.ocessing of p.arl millet p.ses a significant challenge due to its high lip.d content,enzyme activity,and p.esence of ***,it becomes imp.rative to enhance the quality and p.olong the shelf life of p.arl millet flour by emp.oying suitable *** treatment in the food industry has long been seen as p.omising due to its p.tential to reduce microbial load,inactivate enzymes,and imp.ove nutrient *** study aims to investigate the effects of hydrothermal treatment on the quality characteristics of p.arl *** indep.ndent variables of the study were soaking temp.rature(35,45,55℃),soaking time(2,3,4 h),and steaming time(5,10,15 min).Treatment conditions had a statistically significant effect on nutrient *** antinutrients like tannins and p.ytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,resp.ctively,after the *** activity decreased significantly up.to 10% with the treatment *** findings of this study could p.tentially encourage the use of p.arl millet flour in the p.oduction of various food items and p.omote the ap.lication of hydrothermal treatment in the field of food p.ocessing.

关键词： p.arl millet Hydrothermal treatment Nutritional p.op.rties Antinutrients

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