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副标准电离规的校准

中国检验检测 1984年第2期 47-48页

作者： m.hirata 鲁浩昌

一、引言自1964年以来,用电子技术综合研究所的麦氏真空计,对副标准电离规(VS—1)进行了校准。日本真空协会给日本配备了250多个校准了的规。选择 VS-1作为副标准规的主要理由,是因为规的灵敏度一直到可用麦氏真空计测量绝对压强的压强... 详细信息

一、引言自1964年以来,用电子技术综合研究所的麦氏真空计,对副标准电离规(VS—1)进行了校准。日本真空协会给日本配备了250多个校准了的规。选择 VS-1作为副标准规的主要理由,是因为规的灵敏度一直到可用麦氏真空计测量绝对压强的压强范围都是恒定的。近来,已对真空标准的国际比较进行过讨论和试验。为了促进国际真空标准的研

关键词： VS 电离规真空标准收集极

Physicochemical properties of Li_(3)Ba_(2)La_(3)(moO_(4))_(8):Eu,Tb red-emitting phosphor for solid state white lamps

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稀土学报:英文版 2023年第9期41卷 1279-1287,I0001页

作者： Kora Lu Rojas Baldivia Gustavo A.hirata Center for Scientific Research and Higher Education of Ensenada Ensenada Baja California 22860Mexico Center for Nanoscience and Nanotechnology National Autonomous University of Mexico EnsenadaBaja Califomia 22860Mex

In this work,combustion synthesis was used for the first time to fabricate a phosphor material with red emission for applications in solid-state white-light lamps.We synthesized a material with emission wavelength at λ_(em)=617 nm,excited under long UV-blue wavelength based on Eu^(3+),Tb^(3+)-activated molybdates Li_(3)Ba_(2)(La_(1-x-y)Eu_(x)Tb_(y))_(3)(moO_(4))_(8) with 0 ≤ x ≤1 and 0 ≤ y ≤ 1.A series of powder samples were produced by the combustion method and post-annealed at 800℃ in air.The crystalline phase formation was investigated by X-ray diffraction,which reveals the monoclinic C2/c(15) space group.It is observed that crystalline structure and morphology are preserved when the host lattice is doped with Eu^(3+) or Tb^(3+) single ions and co-doped with both ions at different doping concentrations.A detailed characterization by scanning electron microscopy(SEm) and transmission electron microscopy(TEm)shows a similar morphology in all samples:rather large(1-7 μm) agglomerate particles with irregular shapes and surrounded by smaller nanoparticles of 50 nm in size.UV-visible absorption spectra confirm the presence of Eu^(3+) and Tb^(3+) ions.The luminescent properties of the obtained phosphors were studied in detail.Cathodoluminescence measurements indicate that the best emission intensity is for Eu^(3+):Tb^(3+)doping ratios of 80:0,90:0 and 20:80.On the other hand,samples with 80:0,60:40,and 20:80 doping ratios show the highest intensity in a detailed photoluminescence analysis and they exhibit the highest quantum yield values.A complete and efficient energy transfer from the sensitizer Tb^(3+) to the activator Eu^(3+) is observed in all co-doped phosphors post-annealed at 800℃ for 4 h.Thus,the Li_(3)Ba_(2)La_(3)(maO_(4))_(8):Eu^(3+),Tb^(3+) materials fabricated by combustion synthesis are excellent phosphors for being applied as red-emitting component in solid-state white-light lamps due to an improved color rendering index(CRI) that can be obtained under long UV-blue excitation wavelengths.

关键词： molybdate Europium Terbium Luminescence Phosphor-converted LED Rare earths

Increased prevalence of intestinal inflammation in patients with liver cirrhosis

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World Journal of Gastroenterology 1999年第5期5卷 391-396页

作者： Saitoh O Sugi K Lojima K matsumoto H Nakagawa K Kayazawa m Tanaka S Teranishi T hirata I Katsu Ki K Second Department of Internal medicine Osaka Medical College Takatsuki Japan Department of Gastroenterology Ijinkai Takeda General Hospital Kyoto Japan

AIm To investigate the pathophysiology of the digestive tract in patients with liver cirrhosis.mETHODS In 42 cirrhotic patients and 20control subjects, the following fecal proteinswere measured by enzyme-linkedimmunosorb6nt assay: albumin (Alb ),transferrin (Tf), and al-antitrypsin (a,-AT) as amarker for intestinal protein l0ss, hemoglobin(Hb) for bleeding, PmN-eIastase for intestinalinflammation, and secretory lgA for intestinalimmunity.RESULTS The fecaI concentrations of Hb, Alb,Tf, al-AT, and PmN’eIastase were increased in13 (3l%), 8(19%), l0(24%), 6(14%), and 1l(26%) cases among 42 patients, resPectiveIy.F6cal concentration of secretory IgA wasdecreased in 7 (l7%) of 42 patients. However,these fecal concentrations were not related tothe severity or etiology of liver cirrhosis. Theserum Alb level was significantIy decreased inpatients with intestinal protein Ioss c0mpared tothat in patients without intestinal protein loss.CONCLUSION These findings suggest that: rob6sides the weIl’known pathological conditions,Such as bleeding and protein loss, intestinaIinflammati0n and decreased intestinaI immunityare found in cirrhotic patients, @ intestinalprotein loss contributes to hypoalbuminemia incirrhotic patients, and @ intestinaI inflammationshouId not b6 0verlooked in cirrhotic patients,since it may contribute to or cause intestinalprotein Ioss and oth6r various pathologicalconditions.

关键词： liver cirrhosis intestinal inflammation secretory IgA fecal proteins

magnetic Pair-Breaking in Y1-xHoxNi2B2C （x = 0, 0.25, 0.5, 0.75） Single Crystals

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Chinese Physics Letters 2006年第4期23卷 975-977页

作者：赵松睿沈静琴许祝安 Takeya H hirata K Department of Physics Zhejiang University Hangzhou 310027 National Institute for materials Science 1-2-1 Sengen Tsukuba Ibaraki 305-0047 Japan

Temperature-dependent resistivity and magnetic susceptibility were studied for quaternary borocarbide intermetallic compounds Y1-xHoxNi2B2C （x = 0, 0.25, 0.5, 0. 75）, which show coexistence of superconductivity with magnetism. In a normal state, the compounds exhibit conventional metallic behaviour. The Debye temperature θD is derived by fitting the temperature dependence of resistivity to the Bloch-Gruneisen expression, i.e. θD scales with m^-0.5 （m is the averaged atomic mass on the Y^3＋ site）, which means that the acoustic mode of the lattice vibrating spectrum is influenced by the Y^3＋ site atoms. Fitting the temperature-dependent magnetic susceptibility above TN to the Curie-Weiss law, effective magnetic moment μeff is deduced, and then de Gennes factor dG is calculated. It is found that as Ho content increases, μeff as well as dG increases and Tc decreases. moreover, the decrease of Tc scales with dG, i.e., △Te ∝ -nI^2 N （EF ）dG, which is consistent with the prediction of the Abrikosov-Gor＇kov theory. We suggest that pair-breaking effect of magnetic Ho^3＋ ions. The significant impact on To. the depression of Tc could be mainly ascribed to the magnetic change of Debye temperature with Ho content may not have significant impact on Tc.

关键词： ANTIFERROmAGNETIC SUPERCONDUCTOR HONI2B2C ORDER TRANSPORT mETALS

Precipitation analysis of as-cast HK40 steel after isothermal aging

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International Journal of minerals,metallurgy and materials 2017年第10期24卷 1125-1133页

作者： m.L. Saucedo-munoz A. Ortiz-mariscal V.m. Lopez-hirata J.D. Villegas-Cardenas Orlando Soriano-Vargas Erika O. Avila-Davila Instituto Politecnico Nacional (ESIQIE) Apdo. Postal 118-395 Mexico D.F. 07300 Universidad Politecnica Metepec y Tultitlan Edo. Mex. Mexico Tecnológico de Estudios Superiores de Jocotitlan Jocotitlan Edo. Mex. Mexico

As-cast HK40 steel was aged at 700, 800, or 900℃ for times as long as 2000 h. microstructural characterization showed that the primary m_7C_3 carbide network contained a substantial content of manganese, in agreement with the microsegregation of manganese calculated by Thermo-Calc using the Scheil–Gulliver module. The dissolution of primary carbides caused the solute supersaturation of austenite and subsequent precipitation of fine m_(23)C_6 carbides in the austenite matrix for aged specimens. During prolonged aging, the carbide size increased with increasing time because of the coarsening process. A time–temperature–precipitation diagram for m_(23)C_6 carbides was calculated using the Thermo-CalcPRISmA software; this diagram showed good agreement with the experimental growth kinetics of precipitation. The fine carbide precipitation caused an increase in hardness; however, the coarsening process of carbides promoted a decrease in hardness. Nanoindentation tests of the austenite matrix indicated an increase in ductility with increasing aging time.

关键词： as-cast HK40 steel carbide precipitation aging precipitation simulation

Phase separation and coarsening of NiAl(β′)intermetallic in quench-aged Fe-Ni-Al alloys

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Journal of Iron and Steel Research(International) 2020年第11期27卷 1331-1338页

作者： C.Ferreira-Palma J.A.Rosas-Barrios V.m.Lopez-hirata D.I.Rivas-Lopez H.J.Dorantes-Rosales Faculty of Chemical Sciences Universidad VeracruzanaVeracruz 94294Mexico ESIQIE Instituto Politecnico Nacional.UPALMMexico City 07738Mexico

The coarsening behavior of four quench-aged Fe-Ni-AI alloys with different Ni and Al con tents is studied.The alloys were solubilized at 1100℃for 24 h,water-quenched and aged at 850℃for periods ranging from 1 to 100 h to promote phase separation and coarsening.The two alloys with the highest combined Ni and Al contents(>35 at.%)showed signs of spinodal decomposition,while the alloys with lower Ni and Al contents followed a classical nucleation process.Higher Ni and Al contents promoted an increase in NiAl(β′)phase fraction in concordance with phase equilibrium diagrams.The alloy with the highest[3'fraction presented a completely interconnected structure.The coarsening ofβ′particles in the other three alloys followed the predictions of the Lifshitz-Slyozov-Wagner(LSW)theory.The general trend was an increase in the coarsening kinetics with higher Ni and Al contents.The highest hardness was found in the alloys with higher fraction albeit these compositions are less resistant to coarsening and have been reported to present a low room-temperature ductility.

关键词： Precipitation Spinodal decomposition Coarsening Aging Fe-Ni-Al alloy

Two-Phase Flow Regimes and Discharge Characteristics of a Plasma Electrohydrodynamic Atomization

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Plasma Science and Technology 2011年第1期13卷 73-76页

作者：孙明 D.BOROCILO G.D.HARVEL m.IBE H.mATSUBARA P.FANSON H.hirata J.S.CHANG mcIARS McMaster University Institute of Electrostatics Shanghai Maritime University University of Ontario Institute of Technology Toyota motor Corporation Higashi-Fuji R&D Centre Toyota motor Engineering & manufacturing North America

Experimental investigation was conducted to study the flow regimes and discharge characteristics of plasma electrohydrodynamic atomization （EHDA） for decane （CloH22） under pulsed applied negative voltage. The experimental parameters were set as the flow rate of decane from 0 mL/min to 10 mL/min and the DC charging voltage from DC 0 V to 12 V with a pulse repetition rates of 200 Hz. The flow regime of decane was observed and the volume-to-electrical charge ratio was measured. Unlike a conventional EHDA system, the results show that a corona discharge was initiated at the edge of the hollow electrode at a specific corona on-set voltage of -17 kV or -20 kV in the case with or without decane flow, respectively. This phenomenon was defined as plasma EHDA.

关键词： plasma eletrohydrodynamic atomization decane pulsed corona discharge flow regime

Effect of homogenization process on the hardness of Zn-Al-Cu alloys

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International Journal of minerals,metallurgy and materials 2015年第10期22卷 1076-1081页

作者： Jose D.Villegas-Cardenas maribel L.Saucedo-munoz Victor m.Lopez-hirata Antonio De Ita-De la Torre Erika O.Avila-Davila Jorge Luis Gonzalez-Velazquez Department of metallurgy and materials Instituto Politecnico Nacional(IPN-ESIQIE)Mexico City 07300Mexico Department of Industrial Engineering Universidad Politecnica del Valle de MexicoMexico CityMexico Department of materials Universidad Autonoma Metropolitana(UAM)Unidad AzcapotzalcoMexico

The effect of a homogenizing treatment on the hardness of as-cast Zn–Al–Cu alloys was investigated. Eight alloy compositions were prepared and homogenized at 350 °C for 180 h, and their Rockwell 'B' hardness was subsequently measured. All the specimens were analyzed by X-ray diffraction and metallographically prepared for observation by optical microscopy and scanning electron microscopy. The results of the present work indicated that the hardness of both alloys(as-cast and homogenized) increased with increasing Al and Cu contents; this increased hardness is likely related to the presence of the θ and τ′ phases. A regression equation was obtained to determine the hardness of the homogenized alloys as a function of their chemical composition and processing parameters, such as homogenization time and temperature, used in their preparation.

关键词： zinc–aluminum–copper alloys casting hardness homogenization phases microstructure

Kynurenine plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate-induced colitis in mice

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World Journal of Gastroenterology 2020年第9期26卷 918-932页

作者： Chieko Tashita masato Hoshi Akihiro hirata Kentaro Nakamoto Tatsuya Ando Takayuki Hattori Yasuko Yamamoto Hiroyuki Tezuka Hiroyuki Tomita Akira Hara Kuniaki Saito Department of Disease Control and Prevention Fujita Health University Graduate School of Health SciencesToyoake 470-1192Japan Department of Biochemical and Analytical Science Fujita Health University Graduate School of Health SciencesToyoake 470-1192Japan Division of Animal Experiment Life Science Research CenterGifu UniversityGifu 501-1193Japan Department of Cellular Function Analysis Research Promotion and Support HeadquartersFujita Health University Graduate School of Health SciencesToyoake 470-1192Japan Faculty of medical Technology Gifu University of Medical ScienceGifu 501-3892Japan Department of Tumor Pathology Gifu University Graduate School of MedicineGifu 501-1193Japan

BACKGROUND Inflammatory bowel disease,such as Crohn’s disease and ulcerative colitis,is characterized by chronic intestinal inflammation leading to intestinal mucosal damage.Inflammatory bowel disease causes dysregulation of mucosal T cell responses,especially the responses of CD4+T cells.Previously,we demonstrated that indoleamine-2,3-dioxygenase plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate(TNBS)-induced colitis.Although indoleamine-2,3-dioxygenase exerts immunosuppressive effects by altering the local concentration of tryptophan(Trp)and immunomodulatory Trp metabolites,the specific changes in immune regulation during colitis caused by Trp metabolites and its related enzymes remain unclear.AIm To investigate role of kynurenine 3-monooxygenase(KmO)in TNBS-induced colitis and involvement of Trp metabolites in maintenance of intestinal homeostasis.mETHODS Colitis was induced in eight-week-old male KmO+/+or KmO−/−mice of C57BL/6N background using TNBS.Three days later,the colon was used for hematoxylin-eosin staining for histological grading,immunohistochemical or immunofluorescence staining for KmO,cytokines,and immune cells.Inflammatory and anti-inflammatory cytokines were measured using quantitative RT-PCR,and kynurenine(Kyn)pathway metabolites were measured by high-performance liquid chromatography.The cell proportions of colonic lamina propria and mesenteric lymph nodes were analyzed by flow cytometry.RESULTS KmO expression levels in the colonic mononuclear phagocytes,including dendritic cells and macrophages increased upon TNBS induction.Notably,KmO deficiency reduced TNBS-induced colitis,resulting in an increased frequency of Foxp3+regulatory T cells and increased mRNA and protein levels of antiinflammatory cytokines,including transforming growth factor-βand interleukin-10.CONCLUSION Absence of KmO reduced TNBS-induced colitis via generation of Foxp3+regulatory T cells by producing Kyn.Thus,Kyn may play a therapeutic role in colon protection during colitis.

关键词： Kynurenine 3-monooxygenase Kynurenine Regulatory T cell Inflammatory bowie diseases