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Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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international Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 362-373页

作者： f.Akbari M.Golkaram S.Beyrami G.Shirazi K.Mantashloo r.Taghiabadi M.Saghafi Yazdi i.Ansarian Department of Metallurgy and Material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCr).According to the results,by increasing the SCr from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCr also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 MPa,an in-crease in the SCr from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： Cruz i.Velasco Valerio Di Giulio f.Javier García de Abajo iCfo-institut de Ciencies fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain iCrEA-institucióCatalana de recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects.

关键词： temperature quantum macroscopic

on the analytical solution of transient friction in channel flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： f.J.GArCíA-GArCíA P.fAri?AS-ALVAri?o Department of Naval & industrial Engineering Polytechnic School of EngineeringUniversity of A Coru?a Campus Industrial de Ferrol integraciones Técnicas de Seguridad S.A. Pol.Ind.Espíritu Santo

The transient friction in channel mean flows is the sum of two contributions,i.e., the underlying laminar flow(ULf) and the purely turbulent component(PTC), and the contributions are analyzed separately by theoretical experiments. it is found that,the transient friction may be higher or remarkably lower than that in equal-reynolds number steady-state flows. The universal time constant for plane-parallel laminar flows is reported, and the role of the time constant in a turbulent mean flow is examined. it is shown that the time constant is related to the turbulence's frozen time. finally, a study of the logarithmic layer during the transient flow is accomplished, which shows that the logarithmic layer is destroyed.

关键词： 76D05 76D06 76f55 o361 transient flow transient friction unsteady channel flow

Effects of synthesis parameters on the performance of crosslinked Co-polymers with clays for conformance control

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Petroleum research 2024年第1期9卷 98-108页

作者： A.A.roslan N.A.A.Aziz N.f.A.Deraman i.Dzulkarnain Petroleum Engineering Department Centre of Research Enhanced Oil Recovery(COREOR)Universiti Teknologi PETRONASSeri IskandarPerakMalaysia Chemical Engineering Department Centre of Research Enhanced Oil Recovery(COREOR)Universiti Teknologi PETRONASSeri IskandarPerakMalaysia

Conformance control or water shut-off is a technique used to improve oil *** conformance control,polymers block high permeability water areas and redistribute water drive toward unswept oil *** this study,co-polymers(denoted ATP-PGV/AM-co-AMPS)were synthesized using acrylamide(AM)and 2-acrylamide-2-methylpropane sulfonic acid(AMPS)as the monomers,polyethylene glycol(PEG)-200 and methylenebisacrylamide(MBA)as the crosslinkers,attapulgite(ATP)and bentonite(PGV)as the clay types,and ammonium persulfate(APS)as the initiator,in addition to paraffin oil and *** were synthesized using inverse emulsion polymerization with different concentrations of monomers,crosslinkers,and clays,and they were characterized using fourier-transform infrared(fTir)spectroscopy and scanning electron microscopy(SEM)with energy dispersive X-ray spectroscopy(EDX).fTir spectra of the samples confirmed the existence of sulfonate and hydroxyl groups,which are important for polymer ***-EDX images indicated that the morphology and elemental composition were different before and after swelling,confirming the occurrence of ***,samples were placed in sodium chloride solution(20,000 ppm)for 7 days to evaluate swelling at both room temperature and 90°*** analysis(TGA)and differential scanning calorimetry(DSC)were used to determine the thermal characteristics of the ***,rheological measurements were used to assess the deformation and rheological behavior of the *** results showed that after 1 day,good swelling without loss of mechanical strength was achieved with the composite synthesized using 10%AM,15%AMPS,6%PGV,and 10%ATP.

关键词： Polymer Clay Water shut-off Conformance Swelling

A Hybrid Cybersecurity Algorithm for Digital image transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa f.Soliman fatma E.fadl-Allah Walid El-Shafai Mahmoud i.Aly Maali Alabdulhafith fathi E.Abd El-Samie Department of information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single carrier frequency Division Multiple Access(SC-fDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power ratio(PAPr).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-fDMA systemas an adopted communication *** introduces a robust image communication framework over SC-fDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-fDMA *** linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-fDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Considerations for the use of porcine organ donation models in preclinical organ donor intervention research

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Animal Models and Experimental Medicine 2024年第3期7卷 283-296页

作者： frazer i.Heinis Shaheed Merani Nicholas W.Markin Kim f.Duncan Michael J.Moulton Lance fristoe William E.Thorell raechel A.Sherrick Tami r.Wells Matthew T.Andrews Marian Urban School of Natural resources Institute of Agriculture and Natural ResourcesUniversity of Nebraska-LincolnLincolnNebraskaUSA Division of transplantation and Vascular Surgery Department of SurgeryUniversity of Nebraska Medical CenterOmahaNebraskaUSA Department of Anesthesiology University of Nebraska Medical CenterOmahaNebraskaUSA Division of cardiothoracic Surgery Department of SurgeryUniversity of Nebraska Medical CenterOmahaNebraskaUSA Clinical Perfusion Nebraska Medicine-Nebraska Medical CenterOmahaNebraskaUSA Department of Neurosurgery University of Nebraska Medical CenterOmahaNebraskaUSA Nutrition and Health Sciences College of Education and Human SciencesUniversity of Nebraska-LincolnLincolnNebraskaUSA Department of Comparative Medicine University of Nebraska Medical CenterOmahaNebraskaUSA

Use of animal models in preclinical transplant research is essential to the optimization of human allografts for clinical *** models of organ donation and preservation help to advance and improve technical elements of solid organ recovery and facilitate research of ischemia-reperfusion injury,organ preservation strategies,and future donor-based *** considerations include cost,public opinion regarding the conduct of animal research,translational value,and relevance of the animal model for clinical *** present an overview of two porcine models of organ donation:donation following brain death(DBD)and donation following circulatory death(DCD).The cardiovascular anatomy and physiology of pigs closely resembles those of humans,making this species the most appropriate for pre-clinical *** are also considered a potential source of organs for human heart and kidney *** is imperative to minimize animal loss during procedures that are surgically *** present our experience with these models and describe in detail the use cases,procedural approach,challenges,alternatives,and limitations of each model.

关键词： animal model brain death circulatory death organ transplantation

Effect of drug therapies on self-reported chemosensory outcomes after CoViD-19

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World Journal of otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 88-96页

作者： Marco A.fornazieri Bruno M.Cunha Samuel P.Nicácio Lucas K.Anzolin JoséL.B.da Silva Aristides fernandes Neto Deusdedit Brandão Neto richard L.Voegels fábio D.r.Pinna Department of Surgery Londrina State UniversityLondrinaBrazil Department of Medicine Pontifical Catholic University of ParanáLondrinaBrazil Department of otorhinolaryngology University of São PauloSao PauloBrazil Department of otorhinolaryngology:Head and Neck Surgery Perelman School of MedicineSmell and Taste CenterUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA

objective:The aim of this study was to assess the relative efficacy of medications used following severe acute respiratory syndrome coronavirus-2(SArS-CoV-2)infection on self-reported alterations in taste and/or smell ***:Seven hundred and fourteen persons with self-reported postcoronavirus disease 2019(post-CoViD-19)chemosensory disorders were personally interviewed regarding specific medications they were administered following the acute phase of the *** dependent measure—self-reported total recovery of chemosensory symptoms—was subjected to stepwise logistic *** predictors included demographic and clinical variables,in addition to specific medications used to mitigate disease symptoms(i.e.,systemic corticosteroids,oseltamivir,vitamin C,ibuprofen,hydroxychloroquine,azithromycin,ivermectin,nitazoxanide,anticoagulants,and zinc).results:The median time between CoViD-19 symptom onset and the interviews was 81 days(interquartile range:60-104).of the 714 subjects,249(34.9%)reported total recovery of their chemosensory function;437(61.2%)had at least one treatment since the beginning of the *** and those with more comorbidities had undergone more *** recovery rates of the treated and nontreated groups did not differ ***,respondents who had used nitazoxanide tended to have a higher rate of self-reported taste or smell *** who took oral zinc were less likely to ***:No medication employed during the first months after SArS-CoV-2 infection had a clear positive effect on returning self-reported smell or taste function to normal,although nitrazoxide trended in a positive *** zinc had a negative effect on the reported recovery of these senses.

关键词： chemosensory disorder coronavirus infections CoViD-19 drug therapy SArS-CoV-2 smell loss taste loss

Microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and fisheries 2024年第1期9卷 57-65页

作者： Mohammed f.El Basuini Mohamed A.A.Zaki Abdelaziz M.El-Hais Mohamed G.Elhanafy Emad H.El-Bilawy Amr i.Zaineldin Mohamed f.A.Abdel-Aziz ibrahim A.Abouelsaad ibrahim TEl-ratel Kumbukani Mzengereza ronick S.Shadrack islam i.Teiba faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman international University South Sinai46618Egypt faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal Health research institute(AHri-DoKi) Agriculture Research CenterGiza12619Egypt fish rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt Horticulture Department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt Department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan Department of Aquatic and fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi faculty of Aquaculture and Marine fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).fishes(n=225;initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SoD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin Gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress

Mutations of voltage-gated sodium channel contribute to pyrethroid resistance in Panonychus citri

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insect Science 2024年第3期31卷 803-816页

作者： Deng Pan Qiu-Juan Luo Andrias o.o'reilly Guo-rui Yuan Jin-Jun Wang Wei Dou Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionAcademy of Agricultural SciencesSouthwest UniversityChongqingChina Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze river(Ministry of Education) Academy of Agricultural SciencesSouthwest UniversityChongqingChina School of Biological and Environmental Sciences Liverpool John Moores UniversityLiverpoolUK

insecticide resistance in Panonychus citri is a major obstacle to mite control in citrus *** insecticides are continually used to control mites in China,although resistance to pyrethroids has evolved in some ***,the resistance to the pyrethroid fenpropathrin was investigated and 7 out of 8 field-collected populations of P citri exhibited a high level of resistance,ranging from 171-fold to 15391-fold higher than the susceptible(SS)comparison *** voltage-gated sodium channel(VGSC)mutations were identified in the tested populations:L1031V,f1747L,and *** sequencing was used to evaluate the frequency of these mutations in the 19 field populations.L1031V and f1751i were present in all populations at frequencies of 11.6%-82.1%and 0.5%-31.8%,respectively,whereas the f1747L mutation was only present in 12 populations from Chongqing,Sichuan,Guangxi,and Yunnan *** of these mutations singly or in combination into transgenic flies significantly increased their resistance to fenpropathrin and these flies also exhibited reduced mortality after exposure to the pyrethroids permethrin andβ-*** citri VGSC homology modeling and ligand docking indicate that f1747 and f1751 form direct binding contacts with pyrethroids,which are lost with mutation,whereas L1031 mutation may diminish pyrethroid effects through an allosteric ***,the results provide molecular markers for monitoring pest resistance to pyrethroids and offer new insights into the basis of pyrethroid actions on sodium channels.

关键词： amplicon sequencing kdr mutation molecular docking Panonychus citri pyrethroid resistance transgenic flies