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Journal of materials Science & technology 2021年第34期93卷 60-70页

作者： Z.H.wang B.Niu Q.wang C.Dong J.C.Jie t.m.wang t.G.Nieh Key Laboratory of materials modification by Laser Ion and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Department of materials Science and Engineering The University of TennesseeKnoxville37996TennesseeUSA

the development of ultrastrong maraging stainless steels(mSSs)is always in high ***,traditional high-strength mSSs generally exhibit early plastic instability with a low uniform strain since the precipitated nanoparticles are non-coherent with the body-centered-cubic(BCC)lath martensitic ***,we design a novel ultrahigh strength mSS(Fe-5.30 Cr-13.47 Ni-3.10 Al-1.22 mo-0.50 W-0.23 Nb-0.03 C-0.005 B,wt.%)using a cluster formula approach.A fabulous microstructure consisting of a uniform distribution of high-density coherent B2-Ni Al nanoprecipitates(3-5 nm)in BCC martensitic matrix was successfully *** alloy has not only an exceedingly high ultimate tensile strength of 2.0 GPa,but also a decent uniform elongation of 4.2%-5.1%,which is almost triple of the value observed in existing *** present an in-depth discussion on the origins of ultrahigh strength and uniform plastic strain in the new alloy to validate our design strategy and further offer a new pathway to exploit highperformance mSSs.

关键词： maraging stainless steel Ultrahigh strength Coherent precipitation Strengthening mechanisms Uniform deformation

Novel insight into dry sliding behavior of Cu-Pb-Sn in-situ composite with secondary phase in different morphology

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Journal of materials Science & technology 2020年第5期40卷 158-167页

作者： B.W.Dong S.H.wang Z.Z.Dong J.C.Jie t.m.wang t.J.Li School of material Science and Engineering Dalian University of TechnologyDalian 116024China

the Cu-24 Pb-x Sn(wt%)(x=0,2,4,6)alloys with Pb-rich second-phase particles(SPPs)in different shapes show obviously differently mechanical and self-lubricating *** influence of the SPPs’shape difference on the alloys’mechanical and self-lubricating properties was ***-24 Pb alloy with continuously netty SPPs shows much more intensive stick-slip phenomenon during dry sliding than the other three alloys with independently rodlike *** is mainly due to insufficient lubrication resulted by the netty SPPs’splitting *** the SPPs transforming from netty to rodlike shape under the addition of Sn,the stick-slip phenomenon was notably weakened,which was proven to be related to the higher self-lubricating property of alloys with rodlike ***,the simultaneous increase of ductility and tensile strength was observed in the Cu-24 Pb-x Sn alloys with increasing Sn content,which is because the netty SPPs’splitting behavior will be weakened with them replaced by the rodlike SPPs.

关键词： Second-phase particles Netty shape Rodlike shape Stick-slip mechanical property Self-lubricating property

modified endoscopic transnasal orbital apex decompression in dysthyroid optic neuropathy

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Eye and Vision 2021年第1期8卷 183-191页

作者： Yunhai tu mingna Xu Andy D.Kim michael t.m.wang Zhaoqi Pan Wencan Wu the Eye Hospital of Wenzhou medical University No.270 Xueyuan Xi RoadWenzhouZhejiang 325027P.R.China Department of Ophthalmology New Zealand National Eye CentreThe University of AucklandAucklandNew Zealand

Background:to describe the surgical technique and assess the clinical efficacy and safety of modified endoscopic transnasal orbital apex decompression in the treatment of dysthyroid optic ***:In this retrospective research,forty-two subjects(74 orbits)who underwent modified endoscopic transnasal orbital apex decompression for the treatment of dysthyroid optic neuropathy were *** and postoperative best-corrected visual acuity(BCVA),visual field mean deviation(mD),Hertel exophthalmometry,and new onset diplopia were assessed before and after the *** Wilcoxon test was used for differential *** mixed-models’analyses were conducted to assess the potential predictors for BCVA ***:Postoperatively,the mean BCVA improved from 0.70±0.62 logmAR to 0.22±0.33 *** significantly improved in 69 eyes(93%),remained stable in 4 eyes(5%)and deteriorated in 1 eye(1%).mD of visual fields improved from−13.73±9.22 dB to−7.23±7.04 *** decreased from 19.57±3.38mm to 16.35±*** BCVA,mD of visual fields and medical rectus diameter were independent factors associated with improvements in BCVA(Pmixed-models’*** patients(42.9%)developed new diplopia ***:modified endoscopic transnasal orbital apex decompression effectively restores vision in dysthyroid optic neuropathy.

关键词： Endoscopic transnasal orbital decompression Dysthyroid optic neuropathy thyroid-associated ophthalmopathy Visual acuity Visual field

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振荡式小型氢脉泽的特性

宇航计测技术 1984年第S1期 201-206页

作者： Harry t.m.wang 唐建康

本文对CHYmNS-Ⅰ型和CHYmNS-Ⅱ振荡式小型氢脉泽和它们的稳定度性能作了说明。两种脉泽的工作原理完全相同,但体积和重量相差很大。它们可以采用小型化腔体结构。由稳定性数据能够判断,当脉泽体积减小时,性能有所下降。CHYmNS-Ⅰ型的腔... 详细信息

本文对CHYmNS-Ⅰ型和CHYmNS-Ⅱ振荡式小型氢脉泽和它们的稳定度性能作了说明。两种脉泽的工作原理完全相同,但体积和重量相差很大。它们可以采用小型化腔体结构。由稳定性数据能够判断,当脉泽体积减小时,性能有所下降。CHYmNS-Ⅰ型的腔体尺寸是15厘米（外径）×15厘米（长）,τ=100秒时,测出的根值阿仑方差σy（τ）=6.6×10-14。CHYmNS-Ⅱ型的体积较小,相应的数据是11厘米（外径）×15厘米（长）,τ=100秒时,σy（τ）=1.3×10-13。从使用观点看,优先考虑的是它的长期稳定性。两个小型脉泽直接比对测出的数据是:τ=10～5秒时,σy（τ）=4×10-15。这一测试结果说明,用电子的方法稳定腔体,对克服环境扰动的影响是卓有成效的,从而保证脉泽的频率输出长期稳定。

关键词：脉泽腔体振荡式

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利用金属氢化物处理氢激射器中的气体

宇航计测技术 1985年第S1期 1-6页

作者： Harry t.m.wang 唐健康

氢与某些金属和合金之间相互作用的可逆性,在满足氢激射器的氢源供应、氢气流量调节以及保持真空度等方面,得到了十分有效的应用。此外,氢化物在减小激射器的体积、重量和功耗以及改进系统的可靠性等方面都有重要作用。可供振荡式小型... 详细信息

氢与某些金属和合金之间相互作用的可逆性,在满足氢激射器的氢源供应、氢气流量调节以及保持真空度等方面,得到了十分有效的应用。此外,氢化物在减小激射器的体积、重量和功耗以及改进系统的可靠性等方面都有重要作用。可供振荡式小型化氢激射器运行七年的氢源,可以存储在50克LaNi5或50克LaNi4.7Al0.3中。包括一个电控钯银合金稳流器在内,氢源所占的容积小于50毫升。为氢激射器配套的吸气剂——离子真空泵组合装置中,用锆石墨作吸气剂。工作经验表明,为确保激射器运行可靠,需要具备洁净的、可烘烤的真空系统。这种真空系统的设计要求是十分严格的。

关键词：激射器量子放大器氢化物氢化合物离子泵真空泵吸气泵吸附泵吸气剂氢源离解压力高压容器压力容器氢气流量流量调节器

HYPOtENSIVE ACtION OF β-(2,2,6,6-tEtRAmEtHYLPIPERIDINO)-EtHYL-GUANIDINE SULPHAtE(BD-31)

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Science in China,Ser.A 1964年第9期 1527-1531页

作者：白东鲁陈维洲王志敏丁光生嵇汝运

One of the antihypertensive drug widely used clinically is guanethidine,[2-(octa-hydro-1-azocinyl)-ethyl]-guanidine *** lowers the high blood pressure slowly butpersistently,and lacks the side effects common to ganglion-blocking *** onthe structure-activity relationship disclosed that the 8-membered ring might be displacedby other appropriate rings without loss of activity,the side chain had to be 2 carbon atomsnot bearing any substituents,and the terminal guanidine-moiety might be replaced byamidine or amidoxime without reducing the hypotensive effect.

关键词： BD-31 tEtRAmEtHYLPIPERIDINO HYPOtENSIVE ACtION OF EtHYL-GUANIDINE SULPHAtE

QCD sum rule study of J^(P)=1^(±)exotic states with two heavy quarks in the molecular picture

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Chinese Physics C 2024年第6期48卷 31-37页

作者： t.m.Aliev S.Bilmis m.Savcı Department of Physics Middle East Technical UniversityAnkara06800Turkey tUBItAK ULAKBIm Ankara06510Turkey

In this study,the spectroscopic parameters of exotic molecular states composed of mesons containing two heavy quarks(scalar-axial and pseudoscalar-axial meson combinations)are investigated within the QCD sum *** findings reveal that molecular states containing charm quarks do not form bound states,whereas states with b-quarks can form exotic molecular *** observation has significant implications for understanding the structure of these exotic states.

关键词： QCD sum rules exotic mesons molecular states

Analysis of strong decays of SU(3)partners ofΩ(2012)baryon

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Chinese Physics C 2024年第8期48卷 34-41页

作者： t.m.Aliev S.Bilmis m.Savci Department of Physics Middle East Technical UniversityAnkara 06800Turkey tUBItAK ULAKBIm Ankara 06510Turkey

We estimate the coupling constants and decay widths of the SU(3)partners of theΩ(2012)hyperon,as discovered by the BELLE Collaboration,using the distribution amplitudes of the octet baryons within the light cone sum rules *** study includes a comparison of the obtained results for the relevant decay widths with those derived within the framework of the flavor SU(3)*** observe a good agreement between the predictions of both ***,our result on the decay width ofΩ→ΞK is compatible with the existing experimental result within the uncertainties of the model *** results can provide helpful insights for determining the nature of the SU(3)partners of theΩ(2012)baryon.

关键词： coupling constants light cone sum rule hyperon

Distribution, health and ecological risk assessments of trace elements in Nigerian oil sands

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Acta Geochimica 2024年第1期43卷 59-71页

作者： Odunayo t.Ore Festus m.Adebiyi Department of Chemistry Obafemi Awolowo UniversityIle-Ife 220005Nigeria Department of Chemical Sciences Achievers UniversityOwoNigeria

the Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. In the present study, we investigated the distribution pattern of 18trace elements(including biophile and chalcophile elements) as well as the estimated risks associated with exposure to these elements. the results of the study indicated that Fe was the most abundant element, with a mean concentration of 22,131 mg/kg while Br had the lowest mean concentration of 48 mg/kg. the high occurrence of Fe and ti suggested a possible occurrence of ilmenite(Fe tiO_(3)) in the oil sands. Source apportionment using positive matrix factorization showed that the possible sources of detected elements in the oil sands were geogenic, metal production, and crustal. the contamination factor, geo-accumulation index, modified degree of contamination, pollution load index, and Nemerow pollution index indicated that the oil sands are heavily polluted by the elements. Health risk assessment showed that children were relatively more susceptible to the potentially toxic elements in the oil sands principally via ingestion exposure route(HQ > 1E-04). Cancer risks from inhalation are unlikely due to CR t ingestion and dermal contact pose severe risks(CR > 1E-04). the high concentrations of the elements pose serious threats due to the potential for atmospheric transport, bioaccessibility, and bioavailability.

关键词： Biophile Chalcophile Oil sand Risk assessment trace element

A Preliminary Comparative Study on the Centering Algorithms for CassiniISS NAC Images

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： t.Liang Q.-F.Zhang G.-m.Liu W.-H.Zhu C.-S.wang Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining high precision is an important consideration for astrometric studies using images from the Narrow Angle Camera(NAC)of the Cassini Imaging Science Subsystem(ISS).Selecting the best centering algorithm is key to enhancing astrometric *** this study,we compared the accuracy of five centering algorithms:Gaussian fitting,the modified moments method,and three point-spread function(PSF)fitting methods(effective PSF(ePSF),PSFEx,and extended PSF(x PSF)from the Cassini Imaging Central Laboratory for Operations(CICLOPS)).We assessed these algorithms using 70 ISS NAC star field images taken with CL1 and CL2 filters across different stellar *** ePSF method consistently demonstrated the highest accuracy,achieving precision below 0.03 pixels for stars of magnitude *** to the previously considered best,the modified moments method,the e PSF method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSF model provided by CICLOPS had lower precision than the ***,the ePSF exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy might be attributed to the xPSF focusing on photometry rather than *** findings highlight the necessity of constructing PSF models specifically tailored for astrometric purposes in NAC images and provide guidance for enhancing astrometric measurements using these ISS NAC images.

关键词： methods:analytical techniques:image processing stars:imaging astrometry