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Pressurized environments directly influence friction and wear of dry steel contacts—Investigations in a novel high fluid pressure tribometer

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Friction 2024年第7期12卷 1599-1617页

作者： Paul ReICHLe Jakob BARZ georg UmLAUF günter e.m.TOVAR Institute of Interfacial Process engineering and Plasma Technology(IgVP) University of StuttgartStuttgart 70569Germany Fraunhofer Institute for Interfacial engineering and Biotechnology(IgB) Stuttgart 70569Germany

To reduce the usage of classical lubricants in deep drawing,a new tribological system based on volatile lubricants was ***,a volatile medium is injected under high pressure into the interstice between drawing tool and sheet *** on temperature and pressure,the temporary lubricant may exist in its gaseous or liquid *** this study,a novel high fluid pressure tribometer was designed to investigate the friction and wear of dry steel contacts under comparable conditions like in dry deep ***,a new ball-on-disc tribometer was designed and integrated into a high-pressure *** specifically investigate the effects of different environments(technical air,liquid and gaseous carbon dioxide,nitrogen,argon)at atmospheric and high pressure(0.1 mPa,6 mPa)on tribology,the specimens and all components were operating *** the experiments,the friction was measured *** show that the highest friction occurs in air and the lowest in carbon dioxide *** to the experiments,the wear of the specimens was assessed along with changes in surface chemistry related to tribochemical ***,the tribology of the dry sliding contacts is correlated to changes of the surface *** differences as well as similarities regarding the different fluid environments are *** the results show,the differences between the media used are most pronounced at elevated ***,this work gives clear indications on the suitability of volatile lubricants in dry friction or rather gas lubrication,especially for dry deep drawing.

关键词： dry friction and dry wear gas lubrication carbon dioxide tribo-layer dry metal forming

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Collective coherent emission of electrons in strong laser fields and perspective for hard x-ray lasers

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matter and Radiation at extremes 2024年第2期9卷 1-3页

作者： e.g.gelfer A.m.Fedotov O.Klimo S.Weber extreme Light Infrastructure eRIC ELI Beamlines Facility25241 Dolní BřežanyCzech Republic HiLASe Centre Institute of Physics of the Czech Academy of Sciences25241 Dolní BřežanyCzech Republic National Research Nuclear University mePhI Moscow 115409Russia FNSPe Czech Technical University in Prague11519 PragueCzech Republic

Coherent motion of particles in a plasma can imprint itself on *** recent advent of high-power lasers—allowing the nonlinear inverse Compton-scattering regime to be reached—has opened the possibility of looking at collective effects in laser–plasma *** certain conditions,the collective interaction of many electrons with a laser pulse can generate coherent radiation in the hard x-ray *** perspective paper explains the limitations under which such a regime might be attained.

关键词： laser scattering coherent

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Combination treatment of inflammatory bowel disease:Present status and future perspectives

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World Journal of gastroenterology 2024年第15期30卷 2068-2080页

作者： John K Triantafillidis Constantinos g Zografos manousos m Konstadoulakis Apostolos e Papalois Inflammatory Bowel Disease Unit "Metropolitan General"HospitalHolargos 15562AtticaGreece Hellenic Society for gastrointestinal Oncology 354 Iera OdosChaidari 12461AtticaGreece The 2^(nd)Department of Surgery University of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece Unit of Surgical Research and Training The 2^(nd)Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece

The treatment of patients with inflammatory bowel disease(IBD),especially those with severe or refractory disease,represents an important challenge for the clinical *** seems to be no exaggeration to say that in these patients,not only the scientific background of the gastroenterologist is tested,but also the abundance of“gifts”that he should possess(insight,intuition,determ-ination,ability to take initiative,etc.)for the successful outcome of the *** daily clinical practice,depending on the severity of the attack,IBD is treated with one or a combination of two or more pharmaceutical *** combin-ations include not only the first-line drugs(e.g.,mesalazine,corticosteroids,antibiotics,etc)but also second-and third-line drugs(immunosuppressants and biologic agents).It is a fact that despite the significant therapeutic advances there is still a significant percentage of patients who do not satisfactorily respond to the treatment ***,a part of these patients are going to *** recent years,several small-size clinical studies,reviews,and case reports have been published combining not only biological agents with other drugs(e.g.,immunosuppressants or corticosteroids)but also the combination of two biologi-cal agents simultaneously,especially in severe *** our opinion,it is at least a strange(and largely unexplained)fact that we often use combinations of drugs in a given patient although studies comparing the simultaneous administration of two or more drugs with monotherapy are very *** mentioned above,there is a timid tendency in the literature to combine two biological agents in severe cases unresponsive to the applied treatment or patients with severe extraintestinal *** appropriate dosage,the duration of the administration,the suitable timing for checking the clinical and laboratory outcome,as well as the treatment side-effects,should be the subject of intense clinical research *** this

关键词： Biologics for immune-mediated conditions Dual-targeted treatment Combination treatment Inflammatory bowel disease Crohn’s

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Investigation of the transformation of organic matter of carbonate deposits of the Semiluksky-mendymsky horizon under hydrothermal conditions

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Petroleum 2024年第2期10卷 216-223页

作者： S.m.Petrov A.I.Lakhova e.g.m.is.eva A.g.Safiulina Institute of Petroleum Chemistry and Nanotechnologies Kazan National Research Technological University Institute of geology and Oil and gas Technologies Kazan Federal University

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the Semiluksko-mendymsky horizon of the Romashkino oil field in a hydrothermal fluid for an hour（with a water-to-rock ratio of 33） at 340℃ and 380℃ and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃ and 17 mPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the SARA analysis,the content of asphaltenes increases and the content of resins,aromatic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃ and 20 mPa increases the degree of kerogen conversion from 12.4% to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃ and 17 mPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C11-C17,C19-C22alkyltrimethylbenzenes *** to IR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aromatic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aromaticity and the content of condensed

关键词： Carbonate deposits Organic matter Hydrothermal fluid mobile hydrocarbons

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A short climatology of black and brown carbon and their sources at a suburban site impacted by smoke in Brazil

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Journal of environmental Sciences 2024年第2期136卷 498-511页

作者： Admir Creso Targino Patricia Krecl gabriel Yoshikazu Oukawa eva maria mollinedo graduate Program in environmental engineering Federal University of TechnologyAv.Pioneiros 3131LondrinaPR 86036-370Brazil Department of environmental engineering Federal University of TechnologyAv.Pioneiros 3131LondrinaPR 86036-370Brazil

emissions from biomass burning challenge efforts to curb air pollution in cities downwind of fire-prone regions,as they contribute large amounts of brown carbon(Br C)and black carbon(BC)*** investigated the patterns of Br C and BC concentrations using Aethalometer data(atλ=370 and 880 nm,respectively)spanning four years at a site impacted by the outflow of *** data required to be post processed for the shadowing effect since,without correction,concentrations would be between 29%and 35%*** Br C concentrations were consistently higher than the BC concentrations,indicating the prevalence of aerosols from biomass *** results were supported by the Angstrom coefficient(A_(370/880)),with values predominantly larger than 1(mean±standard deviation:1.25±0.31).A_(370/880)values below 1 were more prevalent during the wet season,which suggests a contribution from fossil fuel *** observed sharp Br C and BC seasonal signals,with mean minimum concentrations of 0.40μg/m^(3)and 0.36μg/m^(3),respectively,in the wet season,and mean maximum concentrations of 2.05μg/m^(3)and 1.53μg/m^(3)in the dry *** largest concentrations were observed when northerly air masses moved over regions with a high density of fire *** burning of residential solid waste and industrial combustion caused extreme Br C and BC concentrations under favourable wind *** neither pollutant is included in any ambient air quality standards,our results suggest that transboundary smoke may hamper efforts to meet the World Health Organization guidelines for fine particles.

关键词： Light-absorbing carbonaceous matter Black carbon Wildfires Biomass burning Aethalometer

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geophysical evidence of large-scale silica-rich fluid flow above the continental subduction interface

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Science China earth Sciences 2024年第9期67卷 2796-2809页

作者： Yuantong mAO Liang ZHAO marco g.mALUSà Stefano SOLARINO Silvia PONDReLLI Baolu SUN Coralie AUBeRT Simone SALImBeNI elena eva Stéphane gUILLOT State Key Laboratory of Lithospheric and environmental Coevolution Institute of Geology and GeophysicsChinese Academy of Sciences College of earth and Planetary Sciences University of Chinese Academy of Sciences Department of earth and environmental Sciences University of Milano-Bicocca Istituto Nazionale di geofisica e Vulcanologia Osservatorio Nazionale Terremoti Istituto Nazionale di geofisica e Vulcanologia Sezione di Bologna Université grenoble Alpes Université Savoie Mont BlancCNRSIRDUGEISTerre

Fluids in subduction zones can have major effects on subduction dynamics. However, geophysical constraints on the scale and impact of fluid flow during continental subduction are still limited. Here we analyze the VP/VSratios in the Western Alpine region, hosting one of the best-preserved fossil continental subduction zones worldwide, to investigate the impact of fluid flow during continental subduction. We found a belt of high VP/VSratios >1.9 on the upper-plate side of the subduction zone,consistent with a partially serpentinized upper-plate mantle, and a belt of unusually low VP/VSratios e lower-plate side,at depths shallower than 30 km. We propose that these low VP/VSratios result from a widespread network of silica-rich veins,indicating past fluid flow along the continental subduction interface. Our results suggest that past fluid flow may have reduced the effective stress along the subduction interface thus favoring continental subduction.

关键词： Western Alps Crustal structure Receiver function VP/VS ratio Silica enrichment

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enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie e ghasemian Laser and Optics group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of electrical engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

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Design of high-temperature superconductors at moderate pressures by alloying AlH3 or gaH3

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matter and Radiation at extremes 2024年第1期9卷 94-103页

作者： Xiaowei Liang Xudong Wei eva Zurek Aitor Bergara Peifang Li guoying gao Yongjun Tian Center for High Pressure Science(CHiPS) State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China School of materials Science and engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry State University of New York at BuffaloBuffaloNew York 14260-3000USA Physics Department and eHU Quantum Center University of the Basque CountryUPV/EHU48080 BilbaoSpain Donostia International Physics Center(DIPC) 20018 DonostiaSpain Centro de Física de materiales CFm Centro Mixto CSIC-UPV/EHU20018 DonostiaSpain extreme Conditions Physics Research Team College of Physics and Electronic InformationInner Mongolia Minzu UniversityTongliao 028043China

Since the discovery of hydride superconductors,a significant challenge has been to reduce the pressure required for their *** this context,we propose that alloying could be an effective strategy to achieve *** focus on a series of alloyed hydrides with the AmH_(6)composition,which can be made via alloying A15 AH_(3)(A=Al or ga)with m(m=a group IIIB or IVB metal),and study their behavior under *** of them are predicted to maintain the A15-type structure,similar to AH_(3)under pressure,providing a platform for studying the effects of alloying on the stability and superconductivity of AH_(3).Among these,the A15-type phases of AlZrH_(6)and AlHfH_(6)are found to be thermodynamically stable in the pressure ranges of 40–150 and 30–181 gPa,***,they remain dynamically stable at even lower pressures,as low as 13 gPa for AlZrH_(6)and 6 gPa for AlHfH_(6).These pressures are significantly lower than that required for stabilizing A15 ***,the introduction of Zr or Hf increases the electronic density of states at the Fermi level compared with *** enhancement leads to higher critical temperatures(Tc)of 75 and 76 K for AlZrH_(6)and AlHfH_(6)at 20 and 10 gPa,*** the case of gamH_(6)alloys,where m represents Sc,Ti,Zr,or Hf,these metals reinforce the stability of the A15-type structure and reduce the lowest thermodynamically stable pressure for gaH_(3) from 160 gPa to 116,95,80,and 85 gPa,*** noteworthy are the A15-type gamH_(6)alloys,which remain dynamically stable at low pressures of 97,28,5,and 6 gPa,simultaneously exhibiting high Tc of 88,39,70,and 49 K at 100,35,10,and 10 gPa,***,these findings enrich the family of A15-type superconductors and provide insights for the future exploration of high-temperature hydride superconductors that can be stabilized at lower pressures.

关键词： alloying alloys superconductors

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Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

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Journal of Animal Science and Biotechnology 2024年第1期15卷 162-170页

作者： Quinn A.Hoorn gabriel A.Zayas eduardo e.Rodriguez Laura m.Jensen Raluca g.mateescu Peter J.Hansen Department of Animal Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied Systems Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, more than 50% of the energy input to produce a unit of beef is consumed by the female that produced the calf. Development of genomic tools to identify females with high genetic merit for reproductive function could increase the profitability and sustainability of beef *** genome-wide association studies(gWAS) were performed using a single-step genomic best linear unbiased prediction approach on pregnancy outcome traits from a population of Angus–Brahman crossbred heifers. Furthermore, a validation gWAS was performed using data from another farm. Heifers were genotyped with the Bovine ggP F250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of timed artificial insemination(AI) followed by natural mating for 3 months. Two phenotypes were analyzed: pregnancy outcome to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PeBS;n = 1,725). The heritability was estimated as 0.149 and 0.122 for PAI and PeBS, respectively. In the PAI model, one quantitative trait locus(QTL), located between 52.3 and 52.5 mb on BTA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QTLs explaining between 0.5% and 1% of the genetic variation were found on BTA12 and 25. In the PeBS model, a large QTL on BTA7 was synonymous with the QTL for PAI, with minor QTLs located on BTA5, 9, 10, 11, 19, and 20. The validation population for pregnancy status at the end of the breeding season were Angus–Brahman crossbred heifers bred by natural mating. In concordance with the discovery population, the large QTL on BTA7 and QTLs on BTA10 and 12 were *** In summary, QTLs and candidate SNPs identified were associated with pregnancy outcomes in beef heifers, including a large QTL associated with a group of protocadherin genes. Confirmation of these associations

关键词： Beef cattle Fertility gWAS QTL

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Novel Framework for an Intrusion Detection System Using multiple Feature Selection methods Based on Deep Learning

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Tsinghua Science and Technology 2024年第4期29卷 948-958页

作者： A.e.m.eljialy mohammed Yousuf Uddin Sultan Ahmad Department of Information Systems College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAlkharjSaudi Arabia Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAlkharjSaudi Arabiaand also with University Center for Research and Development(UCRD)Department of Computer Science and EngineeringChandigarh UniversityPunjabIndia

Intrusion detection systems (IDSs) are deployed to detect anomalies in real time. They classify a network’s incoming traffic as benign or anomalous (attack). An efficient and robust IDS in software-defined networks is an inevitable component of network security. The main challenges of such an IDS are achieving zero or extremely low false positive rates and high detection rates. Internet of Things (IoT) networks run by using devices with minimal resources. This situation makes deploying traditional IDSs in IoT networks unfeasible. machine learning (mL) techniques are extensively applied to build robust IDSs. many researchers have utilized different mL methods and techniques to address the above challenges. The development of an efficient IDS starts with a good feature selection process to avoid overfitting the mL model. This work proposes a multiple feature selection process followed by classification. In this study, the Software-defined networking (SDN) dataset is used to train and test the proposed model. This model applies multiple feature selection techniques to select high-scoring features from a set of features. Highly relevant features for anomaly detection are selected on the basis of their scores to generate the candidate dataset. multiple classification algorithms are applied to the candidate dataset to build models. The proposed model exhibits considerable improvement in the detection of attacks with high accuracy and low false positive rates, even with a few features selected.

关键词： random forest feature selection decision tree software-defined network logistic regression intrusion detection system XgB classifier AdaBoost

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