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Analysis of delivery and recalculation of dose using DICOM treatment records

Radiation Medicine and Protection 2022年第3期3卷 123-130页

作者： z.Chen M.F.Moyers Y.Deng H.l.Chen J.li z.M.Shen J.lin q.Wang P.Yepes Shanghai Proton and Heavy Ion Center Shanghai Engineering Research Center of Proton and Heavy Ion Radiation TherapyShanghai Key Laboratory of Radiation OncologyShanghai 201315China Rice university HoustonTXUnited States

Objective:A procedure has been proposed for patient-specific qA that,instead of comparing a measurement to the planned dose,compares the dose calculated by an independent system to the dose calculated by the planning *** is still prudent,however,to check the accuracy of the beam *** this purpose,the DICOM records from the first treatment fraction can be compared to the planned treatment using an in-house developed planning ***:Totally 1,398 patient portals were subjected to the new qA *** dose distribution for each portal was first recalculated on a water phantom by two treatment planning systems and the dose distributions were *** agreement was observed,the patient was allowed to start treatment without a *** record from the first day was imported into an in-house planning system which was used to evaluate the delivery for errors and calculate the delivered dose distribution and compare it to the planned dose ***:A total of 266 portals passed a strict comparison between the clinical and qA dose calculations and directly used for treatment without *** those portals,the comparison of the delivery records to the plan showed that 99%of spot positions deviated less than 0.2 mm and 99.7%of spot metersets deviated by less than 0.3%.On the other hand,64 portals showed spot size deviations greater than the tolerance of15%with some as large as25%.For 32 portals in which the record was used to calculate the delivered dose distribution,the Gamma passing rates between the planned and delivered distributions were always above 95%using a 2%dose difference and 2 mm distance-to-agreement ***:The new qA process has been implemented slowly with strict *** amount of beam time required has been reduced while maintaining safety.

关键词： Ion beam quality assurance Monte Carlo DICOM

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Artifact analysis of a far-field coded-aperture gamma camera extended to partially coded field-of-view

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Radiation Detection Technology and Methods 2022年第4期6卷 558-568页

作者： q.W Xliu z.zhang N.Jiang Y.Hou H.zhang Y.Ji l.Sun Y.Xia Beijing Engineering Research Center of Industrial Spectrum Imaging School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingXueyuan Road StreetBeijing 100083China Beijing Novel Medical Equipment ltd. Beijing 102206China CNNC High Energy Equipment(Tianjin)Co.ltd. Tianjin 300300China China Beijing institute of Spacecraft Environment Engineering and Science and Technology on Reliability and Environmental Engineering LaboratoryBeijing 100094China

Purpose Coded-aperture gamma cameras play an important role for homeland security *** have limitedﬁeld-of-view(FOV)which is a critical parameter for many *** FOV can be potentially increased by extending it to the penumbra area(partially coded FOV).Methods In this study,we analyzed this artifact phenomenon based on simulating a commercial coded-aperture gamma *** camera uses a modiﬁed uniformly redundant array(MuRA)mask with a basic pattern of rank *** opening angle of the basic pattern to the detector center is 26.36◦which is the commonly used non-artifact FOV(NAFOV).In some applications,the radiation source is a far-ﬁeld single-point ***,we extend its FOV to 40◦by including a part of the partially coded area,which is a trade-off between the FOV and image *** calculations and simulation studies were carried *** system matrix was calculated using the Sidden’s *** maximum likelihood expectation maximization(MlEM)reconstruction method was *** and reconstruction results of the point source at different positions were *** second moment of inertia was used as theﬁgure of *** Results show that projections have periodic similarity with a period of NAFOV,and reconstructions also have periodic artifacts,i.e.,fromθtoθ+*** are the most serious at the edge of the *** upper and lower artifacts are more serious than the left and right artifacts due to the difference between the horizontal centerline(tungsten)and vertical centerline(holes expect the center unit)of the *** For a point source with high activity,artifacts can be reduced by increasing the iteration number of the MlEM *** at the edge of NAFOV,the point source can be possibly reconstructed thanks to the large size of the position sensitive detector(PSD)*** noise will signiﬁcantly increase artifacts,which may lead to error locate the point source with low activity a

关键词： Homeland security Coded-aperture gamma camera Partially-codedﬁeld-of-view Artifact analysis

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Template-free Fabrication and luminescent Characterization of Highly uniform and Monodisperse Y_2O_2S:Sm^(3+) Hollow Submicrospheres

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Journal of Materials Science & Technology 2012年第7期28卷 666-672页

作者： S.q. Deng z.P. Xue Y.H. Yang q. Yang Y.l. liu Department of Chemistry Jinan University Guangzhou 510632 China

Well dispersed and homogeneous Y2O2S：Sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （SEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. luminescence properties of the Y202S：Sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （uV-lED） or blue lED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

关键词： Yttrium oxysulfide Hollow submicrosphere luminescence long-lasting phosphor

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Fjord-Type AIEgens Based on Inherent Through-Space Conjugation

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CCS Chemistry 2024年第7期6卷 1739-1747页

作者： Ye-qiang Han Yuan Xie Jianyu zhang Shiyu Tan Haoke zhang Ben zhong Tang Jonathan l.Sessler Feihe Huang Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310058 zhejiang-Israel Joint laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215 MOE Key laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058 Center for AIE Research College of Materials Science and EngineeringShenzhen UniversityShenzhen 518061 Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyKowloonHong Kong 999077 School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangzhou 518172 Department of Chemistry The University of Texas at AustinAustinTexas 78712-1224 Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001

Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent ***,the design of efficient luminogens based on TSC is currently challenging due to a lack of established structure-property *** is particularly true in the case of luminogens displaying aggregation-induced emission(AIE)*** this work,three terphenyl derivatives were prepared,and their photophysical properties were systemically *** was found that relative to the corresponding m-and p-linked analogues,the electronic interaction of TBC is weakened while the strength of TSC is commensurately enhanced in the constitutional isomer containing an o-linked fjordtype *** this set of luminogens,the presence of a fjord-type arrangement promotes a transformation from aggregation-caused quenching to *** investigations involving congeneric quaterphenyl and pentphenyl isomers support the universality of the fjord-type unit as a framework for synthesizing AIE-active luminogens(AIEgens)with inherent *** work not only provides a novel set of AIEgens but also establishes the utility of TSC in controlling the photophysical properties of nonconventional and twisted luminogens.

关键词： fjord-type through-space conjugation through-bond conjugation aggregation-induced emission luminescence twisted conformation

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Effect of Ni Content on Mechanical Properties and Corrosion Behavior of Al/Sn－9zn－xNi/Cu Joints

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Journal of Materials Science & Technology 2012年第9期28卷 844-852页

作者： M.l.Huang N.Kang q.zhou Y.z.Huang Key laboratory of liaoning Advanced Welding and Joining Technology School of Materials Science&EngineeringDMian University of TechnologyDalian 116024China

The effects of Ni content on the microstructure and the wetting behavior of Sn-9zn-xNi solders on Al and Cu substrates, as well as the mechanical properties and electrochemical corrosion behavior of Al/Sn-9zn-xNi/Cu solder joints, were investigated. The microstructure of Sn-gzn-xNi revealed that tiny zn and coarsened Ni5zn21 phases dispersed in theβ-Sn matrix. The wettability of Sn-9zn-xNi solders on Al substrate was much better than that on Cu substrate. With increasing Ni content, the wettability on Cu substrate was slightly improved but became worse on Al substrate. In the Al/Sn-9zn-xNi/Cu joints, an Al4.2Cu3.2zn0.7 intermetallic compound （IMC） layer formed at the Sn-gzn-xNi/Cu interfaces, while an Al-zn-Sn solid solution layer formed at the Sn-9zn-xNi/Al interface. The mixed compounds of Ni3Sna and Al3Ni dispersed in the solder matrix and coarsened with increasing Ni content, thus leading to a reduction in shear strength of the Al/Sn-9zn- xNi/Cu joints. Al particles were segregated at both interfaces in the solder joints. The corrosion potentials of Sn-9zn-xNi solders continuously increased with increasing Ni content. The Al/Sn-9zn-0.25Ni/Cu joint was found to have the best electrochemical corrosion resistance in 5% NaCl solution.

关键词： Al-Cu disslmilar-metal solder joint Sn-9zn-xNi Microstructure Mechanicalproperties Electrochemical corrosion Corrosion potential

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Formation of intermetallic phases in unrefined and refined AA6082 Al alloys investigated by using SEM-based ultramicrotomy tomography

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Journal of Materials Science & Technology 2022年第25期120卷 118-128页

作者： J.M.Yu T.Hashimoto H.T.li N.Wanderka z.zhang C.Cai X.l.zhong J.qin q.P.Dong H.Nagaumi X.N.Wang Shagang School of Iron and Steel and High-Performance Metal Structural Materials Research Institute Soochow UniversitySuzhou 215137China School of Materials The University of ManchesterSackville StreetManchester M139PLUK Chinalco Materials Application Research Institute Co.ltd. Beijing 102200China Helmholtz-zentrum Berlin Für Materialien und Energie Hahn-Meitner-Platz 1Berlin 14109Germany Key laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

The spatial arrangement,distribution and morphology of Fe-bearing intermetallics in AA6082 alloys depends on the manufacturing process of the alloy and thus influences the macroscopic ***,the microstructure of a near industrial scale casting AA6082 Al alloy fabricated by:(a)direct chill casting,(b)Al-5 Ti-1 B grain refiner addition and(c)intensive melt shearing has been investigated by threedimensional visualization using SEM-based serial ultra microtomy *** formation sequence of phases in AA6082 alloys is generally categorized into four stages:formation ofα-Al grains,Fe-bearing intermetallics,Mg_(2)Si phase,and eutectic *** of three-dimensional visualization of the microstructure indicated that TiBparticles not only could nucleate Fe-bearingβ-intermetallics,but also could provide substrate for the formation of Fe-bearingα-intermetallics and Mg_(2)Si.A further deep analysis reveals that the essential condition for the formation of secondary phases such as Fe-bearing intermetallics and Mg_(2)Si phase is the build-up of a supersaturated solute front at theα-Al solid-liquid interface irrespective of the specific nucleation *** addition,the results indicate that grain refinement processing causes the severe interconnectivity of Fe-bearingα-***,the intensive melt shearing is a better manufacturing process because the intermetallics are more evenly distributed and refined than with the addition of the grain refiner,thereby improving the properties of the alloy.

关键词： Al-Si-Mg alloy Grain refinement Al-Fe-Si intermetallic phase Tomography ultramicrotomy Mg2Si

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Influencing mechanism of pre-existing nanoscale Al5Fe2 phase on Mg-Fe interface in friction stir spot welded Al-free zK60-q235 joint

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Journal of Materials Science & Technology 2020年第7期42卷 220-228页

作者： R.z.Xu q.Yang D.R.Ni B.l.Xiao C.z.liu z.Y.Ma Institute of Metal Research Chinese Academy of SciencesShenyang110016China College of Material Science and Engineering Shenyang Aerospace UniversityShenyang110136China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign1304 W Green StUrbanaIL61801United States Fredrick Seitz Materials Research laboratory University of Illinois at Urbana-Champaign104 S Goodwin AveUrbanaIL61801United States

Al-free zK60 magnesium (Mg) alloy sheet was selected as substrate material of Mg-steel pinless friction stir spot welding (FSSW), avoiding the effect of the Al element in the substrate on the alloying reaction of Mg-iron (Fe) interface. The sound FSSW joint of zK60 Mg alloy and q235 steel with a hot-dipped aluminum (Al)-containing zinc (zn) coating was successfully realized. The detailed microstructural examinations proved that Al5Fe2 phase at the Mg-Fe interface came from the pre-existing Al5Fe2 phase in the coating and acted as the transition layer for promoting the metallurgical bonding of Mg and Fe. The interfaces with well-matched lattice sites among Fe, Al5Fe2 and Mg were formed during FSSW. A low energy interface with good match of lattice sites ((002)Al5Fe2//(110)Fe, [110]Al5Fe2//[113]Fe) between Al5Fe2 and Fe was identified. For the interface between Al5Fe2 and Mg, an orientation relationship of (622)Al5Fe2//(3112)Mgand[158]Al5Fe2//[2423]Mg was observed. The tensile-shear load of the zK60-steel joint could reach 4.6 kN. Moreover, the joint fracture occurred at the interface between the Al5Fe2 layer and the Mg alloy substrate, suggesting the brittle fracture characteristic.

关键词： Dissimilar welding Friction stir spot welding Magnesium alloys Steels zinc coating

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MICROSTRuCTuRAl STuDY OF Fe-Cr-Al/Al COMPOSITE COATINGS DuRING OXIDATION AND SulFIDATION AT 900℃

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Acta Metallurgica Sinica(English letters) 2007年第2期20卷 87-94页

作者： z.l. zhang D.Y. li X.q. Dong School of Material Science and Engineering Shenyang University of Technology Shenyang 110023 China

The microstructure of a composite coating system, which was composed of an inner layer of Fe-Cr-Al and an outer layer of aluminum, was studied after it was respectively oxidized and sulfurdized at elevated temperatures. Apart from the Al2O3 scale formed on the surface, the microstructure of the composite coatings exposed at 900℃ in air for 4h was a three-layer structure. The first layer consisted of a solid solution of Cr and Fe in α aluminum and an intermetallic compound FeAl3 while the second layer was a single phase of the aluminide and the third layer still remained the same appearance as the original Fe-Cr-Al coating. The microstructural observation of the specimen tested at 850-900℃ at low oxygen pressure and high sulfur pressure for 576h revealed that the surface coatings of the specimen had transformed into a duplex structure containing an outer layer and a thicker aluminide layer beneath. X-ray diffraction results showed that the out layer was composed of Al2S3 and Al2O3 and that AlCrFee was the main phase composition of the aluminide layer, with a few of Al2S3 and Al2O3 accompanied.

关键词： arc spray Fe-Cr-Al composite coating microstructure

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Effects of Current Stressing on Shear Properties of Sn-3.8Ag-0.7Cu Solder Joints

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Journal of Materials Science & Technology 2010年第8期26卷 737-742页

作者： X.J. Wang q.l. zeng q.S. zhu z.G. Wang J.K. Shang Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Effects of electromigration on microstructure, shear strength, and fracture behavior of solder joints were investigated by single-ball shear samples of eutectic Sn-3.8Ag-0.7Cu （SAC） joined by Cu plates at two sides. The electromigration tests were conducted at a current density of about 1.1×10^3 A/cm2 and a working temperature of about 83℃. The results showed that the shear strength and flow stress decreased greatly after current stressing. Such a decrease was associated with no significant loss of the fracture strain at short electromigration but a great reduction in the fracture strain after long-term current stressing. The variation of the fracture strain with the electromigration time was shown to result from the shift of the fracture surface from the center of the solder towards the intermetallic compound （IMC） interface at the cathode.

关键词： Strength Fracture strain Voids Solder

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Effect of grain size on fatigue cracking at twin boundaries in a CoCrFeMnNi high-entropy alloy

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Journal of Materials Science & Technology 2020年第4期39卷 1-6页

作者： A.G.Wang X.H.An J.Gu X.G.Wang l.l.li W.l.li M.Song q.q.Duan z.F.zhang X.z.liao School of Aerospace Mechanical&Mechatronic EngineeringThe University of Sydne0ySydneyAustralia State Key laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Materials Fatigue and Fracture Division Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Max-Planck-Institut für Eisenforschung Max-Planck-Stra?e 140237 DüsseldorfGermany

The fatigue cracking behavior at twin boundaries(TBs)in a Co Cr Fe Mn Ni high-entropy alloy with three different grain sizes was systematically investigated under low-cycle *** of grain size,the change from slip band cracking to TB cracking occurred with increasing the difference in the Schmid factors(DSF)between matrix and ***,the required critical DSF for the transition of the dominant cracking mode decreases with decreasing grain size due to the reduced slip band spacing that increases the impingement sites on the TBs and facilitates the coalescence of defects and voids to initiate TB cracks.

关键词： High-entropy alloy Fatigue cracking Twin boundary Slip band Grain size

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