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稀土元素对2.25Cr-1Mo钢断裂性能的影响

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金属学报 1988年第4期24卷 282-287页

作者：洪友士 w.r.tyson B.FAUCHEr 北京中关村中国科学院力学研究所加拿大CANMET物理冶金实验室

本文用定量金相仪(QTM)和扫描电镜(SEM)测定含与不含稀土元素(rE)的2.25Cr-1Mo钢的夹杂物尺寸及分布;观察断口形态并测定延伸区宽度和韧窝尺度及分布;测定拉伸样品纵剖面上孔洞面密度与真应变的关系.研究表明,添加rE的试验钢中夹杂物密... 详细信息

本文用定量金相仪(QTM)和扫描电镜(SEM)测定含与不含稀土元素(rE)的2.25Cr-1Mo钢的夹杂物尺寸及分布;观察断口形态并测定延伸区宽度和韧窝尺度及分布;测定拉伸样品纵剖面上孔洞面密度与真应变的关系.研究表明,添加rE的试验钢中夹杂物密度较高,在较低的应变下沿夹杂物界面发生孔洞形核、长大和汇合,导致含rE的2.25Cr-1Mo钢较低的室温断裂性能.

关键词： 2.25Cr-1Mo钢断裂性能夹杂物

Dependence of flow strength and deformation mechanisms in common wrought and die cast magnesium alloys on orientation,strain rate and temperature

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Journal of Magnesium and Alloys 2013年第4期1卷 275-282页

作者： S.Xu w.r.tyson r.Eagleson r.Zavadil Z.Liu P.-L.Mao C.-Y.wang S.I.Hill A.A.Luo CanmetMATErIALS Natural Resources Canada183 Longwood Road SouthHamiltonON L8P 0A1Canada School of Material Science and Engineering Shenyang University of Technology111 Shenliao West RoadShenyang 110870PR China University of Dayton research Institute 300 College ParkDaytonOH 45469-0133USA General Motors research&Development Center WarrenMI 48090USA

The controlling plastic deformation mechanisms(*** or twinning)and the structural crash performance of Mg alloys are strongly influenced by loading mode,texture and *** paper summarizes the main results from an experimental program to assess these effects for commercial Mg alloy extrusions(AM30 and AZ31),sheet(AZ31),and high pressure die castings(HPDC,AM50 and AM60).Uniaxial tensile and compressive tests were performed over a wide range of strain rate and temperature(i.e.0.00075–2800 s^(−1) and 100℃ to−150℃)using conventional servo-hydraulic and high-strain-rate universal test machines and a split-Hopkinson-bar(SHB)*** primarily-slip-dominant deformation,the true stress–strain curves showed approximate power-law behavior,and the effects of strain rate and temperature on yield strength could be approximately described by constitutive equations linearly dependent on the rate parameter,Tln(5.3×10^(7)/ɛ˙)where T is test temperature in Kelvin andɛ˙is strain rate in s^(−1).In primarily-twin-dominant deformation,the effects of strain rate and temperature on yield and initial flow stress were negligible or small from quasi-static to 2800 s^(−1) owing to the athermal characteristics of mechanical twinning;the effects may become more pronounced with exhaustion of twinning and increasing proportion of slip.

关键词： Constitutive equation Effects of strain rate and temperature Effects of orientation Crashworthiness Magnesium alloy

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金属晶体中空位的化学位(英文)

稀有金属材料与工程 2000年第5期29卷 301-303页

作者：孙军 r.w.tyson 西安交通大学西安710049 加拿大材料技术国家实验室

本文基于纯金属中的原子 /空位双组元模型 ,由空位的偏摩尔自由能定义给出了金属晶体中空位化学位的表达式。对于含有空位摩尔浓度为 Cν,其热力学平衡态空位摩尔浓度为 C0 的纯金属晶体 ,在环境温度为 T时 ,其空位化学位的表达式则为 ... 详细信息

本文基于纯金属中的原子 /空位双组元模型 ,由空位的偏摩尔自由能定义给出了金属晶体中空位化学位的表达式。对于含有空位摩尔浓度为 Cν,其热力学平衡态空位摩尔浓度为 C0 的纯金属晶体 ,在环境温度为 T时 ,其空位化学位的表达式则为 :μν(Cν) =rT+ rTln(Cν/ C0 ) ;热力学平衡态时为 :μν(C0 ) =rT。上式中的第二项为由 ***[1 ] 所给出的“相对于标准 (热力学平衡 )态的空位化学位”,而第一项则为本文所给出的“标准 (热力学平衡 )

关键词：金属晶体原子/空位双组元模型化学位

Image Splicing Forgery Detection Using Feature-Based of Sonine Functions and Deep Features

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Computers, Materials & Continua 2024年第1期78卷 795-810页

作者： Ala’a r.Al-Shamasneh rabha w.Ibrahim Department of Computer Science College of Computer&Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Computer Science and Mathematics Lebanese American UniversityBeirut11022801Lebanon Department of Mathematics Mathematics Research CenterNear East UniversityNicosia99138Turkey Information and Communication Technology research Group Scientific Research CenterAlayen UniversityDhi Qar64001Iraq

The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research *** of the most popular methods for manipulating digital images is image splicing,which involves copying a specific area from one image and pasting it into *** were made to mitigate the effects of image splicing,which continues to be a significant research *** study proposes a new splicing detectionmodel,combining Sonine functions-derived convex-based features and deep *** stages make up the proposed *** first step entails feature extraction,then classification using the“support vector machine”(SVM)to differentiate authentic and spliced *** proposed Sonine functions-based feature extraction model reveals the spliced texture details by extracting some clues about the probability of image *** proposed model achieved an accuracy of 98.93% when tested with the CASIA V2.0 dataset“Chinese Academy of Sciences,Institute of Automation”which is a publicly available dataset for forgery *** experimental results show that,for image splicing forgery detection,the proposed Sonine functions-derived convex-based features and deep features outperform state-of-the-art techniques in terms of accuracy,precision,and ***,the obtained detection accuracy attests to the benefit of using the Sonine functions alongside deep feature *** the regions or locations where image tampering has taken place is limited by the *** research will need to look into advanced image analysis techniques that can offer a higher degree of accuracy in identifying and localizing tampering regions.

关键词： Image forgery image splicing deep learning Sonine functions

Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： S r wu B Q wang Z w Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the reissner-Nordström-de Sitter BH surrounded by quintessence(rN-dSQ).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant

Liver transplantation as an alternative for the treatment of intrahepatic cholangiocarcinoma: Past, present, and future directions

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 129-138页

作者： Sudha Kodali Ashton A Connor Souhail Thabet Elizabeth w Brombosz r Mark Ghobrial Sherrie and Alan Conover Center for Liver Disease and Transplantation Houston Methodist HospitalHoustonTX 77030USA JC walter Jr Transplant Center Houston Methodist HospitalHoustonTX 77030USA Department of Medicine Weill Cornell Medical CollegeNew YorkNYUSA Department of Surgery Houston Methodist HospitalHoustonTX 77030USA Department of Surgery Weill Cornell Medical CollegeNew YorkNYUSA School of Medicine New Giza UniversityGizaEgypt

Intrahepatic cholangiocarcinoma(iCCA)is a rare biliary tract cancer with high mortality *** resection of the iCCA lesion is the first choice of treatment,with good prognosis after margin-negative ***,only 12%-40% of patients are eligible for resection at presentation due to cirrhosis,portal hypertension,or large tumor *** transplantation(LT)offers margin-negative iCCA extirpation for patients with unresectable ***,iCCA was a contraindication for LT until size-based selection criteria were introduced to identify patients with satisfied post-LT *** studies have shown that tumor biology-based selection can yield high post-LT survival in patients with locally advanced *** selection criterion is the tumor response to neoadjuvant *** with response to neoadjuvant therapy have better outcomes after LT compared with those without tumor response to neoadjuvant *** index that helps predict the treatment outcome is the *** survival outcomes have also opened the door for living donor LT for *** undergoing LT for iCCA now have statistically similar survival rates as patients undergoing *** combination of surgery and locoregional and systemic therapies improves the prognosis of iCCA patients.

关键词： Liver transplantation Cholangiocarcinoma Hepatectomy Transplant oncology Liver neoplasm

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah C.Keles w.r.reed E.Sarver Department of Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： respirable dust Dust control SEM–EDX Scrubber Canopy air curtain Silica

Management of monogenic diabetes in pregnancy:A narrative review

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world Journal of Diabetes 2024年第1期15卷 15-23页

作者： Mohammad Sadiq Jeeyavudeen Sarah r Murray Mark w J Strachan Metabolic Unit Western General HospitalEdinburgh EH42XUUnited Kingdom MrC Centre for reproductive Health University of Edinburgh Queen’s Medical Research InstituteEdinburgh EH164TJUnited Kingdom

Pregnancy in women with monogenic diabetes is potentially complex,with significant implications for both maternal and fetal *** these,maturity-onset diabetes of the young(MODY)stands out as a prevalent monogenic diabetes subtype frequently encountered in clinical *** subtype of MODY requires a distinct approach tailored to the pregnancy,diverging from management strategies in non-pregnant *** MODY(GCK-MODY)typically does not require treatment outside of pregnancy,but special considerations arise when a woman with GCK-MODY becomes *** glycemic targets in GCK-MODY pregnancies are not exclusively dictated by the maternal/paternal MODY genotype but are also influenced by the genotype of the developing *** pregnancy,the choice between sulfonylurea or insulin for treating hepatocyte nuclear factor 1-alpha(HNF1A)-MODY and HNF4A-MODY depends on the mother’s specific circumstances and the available *** of other rarer MODY subtypes is individu-alized,with decisions made on a case-by-case ***,a collaborative approach involving expert diabetes and obstetric teams is crucial for the compre-hensive management of MODY pregnancies.

关键词： Diabetes Pregnancy Maturity-onset diabetes of the young Insulin Sulphonylurea Glucokinase Hepatocyte nuclear factor 1-alpha,hepatocyte nuclear factor 1-beta,and hepatocyte nuclear factor 4-alpha

Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda r.Pereira Martins Natalie B.warren w.Owen McMillan rowan D.H.Barrett redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical researchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. Butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. we then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability