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In situ selective laser gas nitriding for composite TiN/Ti-6Al-4V fabrication via laser powder bed fusion 认领
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作者 P.A.Morton H.C.Taylor +3 位作者 L.E.Murr O.G.Delgado C.A.Terrazas R.B.Wicker 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第10期98-107,共10页
Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with nitrogen.Systematic variation of processing ... Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with nitrogen.Systematic variation of processing parameters allowed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several hundred microns,with TiN dendrite microstructure volume fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness values ranging from~7.5 GPa–9.5 GPa.Embedded TiN hard layers ranging from 50μm to 150μm thick were also fabricated in the laser-beam additively manufactured Ti-6Al-4V alloy producing prototype,hybrid,planar composites having alternating,ductile Ti-6Al-4V layers with a hardness of~4.5 GPa and a stiff,TiN layer with a hardness of~8.5 GPa.The results demonstrate prospects for fabricating novel,additively manufactured components having selective,hard,wear and corrosion resistant coatings along with periodic,planar or complex metal matrix composite regimes exhibiting superior toughness and related mechanical properties. 展开更多
关键词 TI-6AL-4V TiN ceramic coatings and embedded layers Dendritic microstructures Selective laser melting Additive manufacturing Metal matrix composites Selective nitriding
Comparison of Age and Gender Differences of Tryptophan Metabolites in Patients of Major Monopolar and Bipolar Depression 认领
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作者 Hiroi Tomioka Junichi Masuda +1 位作者 Akikazu Takada Akira Iwanami 《食品与营养科学(英文)》 2020年第3期172-185,共14页
Background: No research has been done for the determination of plasma levels of tryptophan metabolites in patients of monopolar and bipolar depression. Methods: Ultra high-speed liquid chromatography/mass spectrometry... Background: No research has been done for the determination of plasma levels of tryptophan metabolites in patients of monopolar and bipolar depression. Methods: Ultra high-speed liquid chromatography/mass spectrometry has been used for the simultaneous determination of plasma levels of tryptophan metabolites in depressive patients. Results: No significant age and gender differences were shown in monopolar depressive patients and some differences were shown in bipolar patients. The administration of drugs such as antidepressants, antipsychotics, mood stabilizers do not seem to have affected the results. Conclusion: In patients of major monopolar depression age and gender differences of plasma levels of tryptophan metabolites disappear although significant differences are observed in healthy volunteers. Some differences of age and gender differences were shown between monopolar and bipolar depressive patients. 展开更多
关键词 DEPRESSION MONOPOLAR DEPRESSION Bipolar DEPRESSION TRYPTOPHAN SEROTONIN 5-Hydroxyindole Acetic ACID Kynurenine 3-Hydroxykynurenine Kynurenic ACID Anthranilic ACID Xanthurenic ACID Indole-3-Acetic ACID SSRI (Selective SEROTONIN REUPTAKE Inhibitor) SNRI (Serotonin Norepinephrine REUPTAKE Inhibitor) Anxiolytic Antipsychotic
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Differences of Plasma Levels of Tryptophan, Serotonin, 5-Hydroxyindole Acetic Acid, and Kynurenine between Healthy People and Patients of Major Monopolar Depression at Various Age and Gender 认领
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作者 Hiroi Tomioka Junichi Masuda +1 位作者 Akikazu Takada Akira Iwanami 《食品与营养科学(英文)》 2020年第6期431-441,共11页
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> It is not well analyze... <b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> It is not well analyzed whether there are differences in plasma levels of tryptophan (TRP) metabolites between healthy control people (HC) and patients of major monopolar depression (MMD). </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Ultra high-speed </span></span><span style="font-family:""><span style="font-family:Verdana;">liquid chromatography/mass spectrometry has been used for the simultaneous determination of plasma levels of tryptophan metabolites in depressive </span><span><span style="font-family:Verdana;">patients. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> There are no significant differences between plasma levels of TRP between HC and MMD. Plasma levels of TRP of HC are higher in young men, young women, old men, and old women in this order. Serotonin (5-HT) levels are higher in MMD than HC. Plasma levels of 5-HIAA of HC are also higher than those of patients of MMD. Plasma levels of kynurenine (KYN) of healthy old men and old women are higher than those of young men and old women. Plasma levels of KYN are higher in old women and young men of MMD than those of HC. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Plasma levels of 5-HT are higher in patients of MMD than those of HC, which may suggest that use of drugs inhibiting the 5-HT transportation may increase plasma levels of 5-HT in MMD. 展开更多
关键词 DEPRESSION Monopolar Depression Bipolar Depression TRYPTOPHAN SEROTONIN 5-Hydroxyindole Acetic Acid KYNURENINE 3-Hydroxykynurenine Kynurenic Acid Anthranilic Acid Xanthurenic Acid Indole-3-Acetic Acid SSRI (Selective Serotonin Reuptake Inhibitor) SNRI (Serotonin Norepinephrine Reuptake Inhibitor)
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基于原子层沉积技术的纳米颗粒表面改性方法 认领
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作者 曹坤 蔡佳明 +1 位作者 单斌 陈蓉 《科学通报:英文版》 SCIE EI CAS CSCD 2020年第8期678-688,M0004共12页
在原子尺度制造方法中,原子层沉积(ALD)是一种依靠表面自限制吸附反应沉积超薄膜的技术,具有优异的制造精度、保型性和沉积均匀一致性等独特优势.本文介绍了ALD技术在纳米颗粒表面改性的最新进展及应用.通过ALD工艺调控可以精准制备致... 在原子尺度制造方法中,原子层沉积(ALD)是一种依靠表面自限制吸附反应沉积超薄膜的技术,具有优异的制造精度、保型性和沉积均匀一致性等独特优势.本文介绍了ALD技术在纳米颗粒表面改性的最新进展及应用.通过ALD工艺调控可以精准制备致密包覆层,多孔包覆层以及表面定向改性构型.纳米级致密包覆层可以隔绝外界环境,提升颗粒稳定性,同时保留颗粒本体性能.多孔包覆层则具有纳米通道,在保留颗粒与外界接触的同时,实现了对进入反应物尺寸的筛选,以及提供了物理限域作用增强稳定性.表面定向改性则能够选择性钝化或者暴露纳米颗粒特定功能表面.ALD的颗粒表面改性技术在电极材料、含能与磁性颗粒的稳定化,催化剂活性位点定向调控等方面具有前瞻性应用.最后,文章展望了ALD进行微纳颗粒表面改性未来面临的挑战和发展方向. 展开更多
关键词 ATOMIC layer deposition Surface FUNCTIONALIZATION CONFORMAL ENCAPSULATION Porous coating Selective DECORATION
Catalytic Performance of Ti<sup>3+</sup>Self-Doped V<sub>2</sub>O<sub>5</sub>-TiO<sub>2</sub>Catalysts for Selective Catalytic Reduction with NH<sub>3</sub> 认领
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作者 Kai Zhang Wei Zhao +1 位作者 Shengping Dou Qian Wang 《材料科学与化学工程(英文)》 2020年第2期16-26,共11页
Ti3+ self-doping modified V2O5/TiO2 catalyst was prepared by sol-gel and impregnation methods and used for selective catalytic reduction (SCR) of NOx with NH3. Results showed that Ti3+ self-doped V2O5/TiO2 catalyst pe... Ti3+ self-doping modified V2O5/TiO2 catalyst was prepared by sol-gel and impregnation methods and used for selective catalytic reduction (SCR) of NOx with NH3. Results showed that Ti3+ self-doped V2O5/TiO2 catalyst performed the better catalytic activity. And X-ray diffraction and scanning electron microscopy were used to evaluate the phase composition and morphology of the prepared catalyst. The effects of calcinations temperature of the support, oxygen concentration, [NH3]/[NO] molar ratio and the GHSV on the denitration performance were investigated. It was found that more than 80% NOx conversion was obtained at 210&#176;C when the O2 volume fraction was 5%, the NO concentration was 500 ppm, the [NH3]/[NO] molar ratio = 1 and the GHSV was 23,885 h&minus;1. The results showed that the catalytic activity increased first with the increasing of O2 concentration and [NH3]/[NO] molar ratio, then remained stable. At the same time, the stability of the catalyst was also studied at the temperature of 210&#176;C. The reaction continued for 750 minutes, and the catalytic activity remained above 80%, indicating that the catalyst has a good stability. Moreover, the Ti3+ self-doped V2O5/TiO2 catalyst also showed good SO2 and H2O resistance. Therefore, these findings provide important information to better understand the application of the prepared catalyst. 展开更多
关键词 Selective CATALYTIC Reduction DENITRIFICATION Operation CONDITION Preparation CONDITION
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Comparison of Plasma Levels of Tryptophan Metabolites between Healthy People and Patients of Bipolar Depression at Various Age and Gender 认领
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作者 Hiroi Tomioka Junichi Masuda +1 位作者 Akikazu Takada Akira Iwanami 《生物医学工程(英文)》 2020年第6期120-129,共10页
Background: It is not well analyzed whether there are differences in plasma levels of tryptophan (TRP) metabolites between healthy control people (HC) and patients of type II bipolar depression (BDII). Methods: Ultra ... Background: It is not well analyzed whether there are differences in plasma levels of tryptophan (TRP) metabolites between healthy control people (HC) and patients of type II bipolar depression (BDII). Methods: Ultra high-speed liquid chromatography/mass spectrometry has been used for the simultaneous determination of plasma levels of tryptophan metabolites in depressive patients. Results: Plasma levels of TRP are not different between HC and patients of BDII. Serotonin (5-HT) levels are higher in BDII than HC. Plasma levels of 5-HIAA of HC are higher than those of old women of BDII, but lower in young women of BDII. Plasma levels of kynurenine (KYN) of HC are not different from those of patients of BDII. Conclusion: Plasma levels of 5-HT are higher in patients of BDII than those of HC, which may suggest that use of drugs inhibiting the 5-HT transportation and lower transporter biding may increase plasma levels of 5-HT in patients of BD. 展开更多
关键词 DEPRESSION Monopolar Depression Bipolar Depression TRYPTOPHAN SEROTONIN 5-Hydroxyindole Acetic Acid KYNURENINE SSRI (Selective Serotonin Reuptake Inhibitor) SNRI (Serotonin Norepinephrine Reuptake Inhibitor) Anxiolytic Antipsychotic
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Preparation of New Uric Acid Sensors Based on Iodide Selective Electrode 认领
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作者 ?ükrü Kalayc? 《美国分析化学(英文)》 2020年第5期205-212,共8页
An electrode for uric acid has been prepared by using an iodide selective electrode with the uricase enzyme. The iodide selective electrode used was prepared from 10% TDMAI and PVC according to our previous study. The... An electrode for uric acid has been prepared by using an iodide selective electrode with the uricase enzyme. The iodide selective electrode used was prepared from 10% TDMAI and PVC according to our previous study. The enzyme was immobilized on the iodide electrode by holding it at pH 7 phosphate buffer for 20 min at room temperature. The H2O2 formed from the reaction of uric acid was determined from the decrease of iodide concentration that was present in the reaction cell. The potential change was linear in the 2 × 10-5 to 2 × 10-4 M uric acid concentration (3 - 34 mg uric acid/100ml blood) range. Uric acid contents of some blood samples were determined with the new electrode and consistency was obtained with a colorimetric method. The effects of pH, iodide concentration, the amount of enzyme immobilized and the operating temperature were studied. No interference of ascorbic acid, glucose and urea was observed. 展开更多
关键词 Uric ACID ELECTRODE URICASE ENZYME IODIDE Selective ELECTRODE Uric ACID in Blood
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Spectral emittance measurements of micro/nanostructures in energy conversion:a review 认领
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作者 Shiquan SHAN Chuyang CHEN +3 位作者 Peter G.LOUTZENHISER Devesh RANJAN Zhijun ZHOU Zhuomin M.ZHANG 《能源前沿:英文版》 SCIE CSCD 2020年第3期482-509,共28页
Micro/nanostructures play a key role in tuning the radiative properties of materials and have been applied to high-temperature energy conversion systems for improved performance.Among the various radiative properties,... Micro/nanostructures play a key role in tuning the radiative properties of materials and have been applied to high-temperature energy conversion systems for improved performance.Among the various radiative properties,spectral emittance is of integral importance for the design and analysis of materials that function as radiative absorbers or emitters.This paper presents an overview of the spectral emittance measurement techniques using both the direct and indirect methods.Besides,several micro/nanostructures are also introduced,and a special emphasis is placed on the emissometers developed for characterizing engineered micro/nanostructures in high-temperature applications(e.g.,solar energy conversion and thermophotovoltaic devices).In addition,both experimental facilities and measured results for different materials are summarized.Furthermore,future prospects in developing instrumentation and micro/nanostructured surfaces for practical applications are also outlined.This paper provides a comprehensive source of information for the application of micro/nanostructures in high-temperature energy conversion engineering. 展开更多
关键词 concentrating solar power(CSP) emittance measurements high temperature MICRO/NANOSTRUCTURE selective absorber selective emitter thermophotovoltaics(TPV)
文章速递Novel advances in metal-based solar absorber for photothermal vapor generation 认领
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作者 Zhengtong Li Chengbing Wang 《中国化学快报:英文版》 SCIE CAS CSCD 2020年第9期2159-2166,共8页
Access to safe drinking water has become an extremely urgent research topic wo rldwide.In recent years,the technology of solar vapor generation has been extensively explored as a potential and effective strategy of tr... Access to safe drinking water has become an extremely urgent research topic wo rldwide.In recent years,the technology of solar vapor generation has been extensively explored as a potential and effective strategy of transforming elements content in seawater.In this review,the basic concepts and theories of metal-based photothermal vapor generation device(PVGD) with excellent optical and thermal regulatory are introduced.In the view of optical regulation,how to achieve high-efficiency localized evaporation in different evaporation system(i.e.,volumetric solar heating and interface solar heating) is discussed;from the aspect of thermal regulation,the importance of selective absorption surface for interfacial PVGD is analyzed.Based on the above discussion and analysis,we summarize the challenges of metal-based desalination device. 展开更多
关键词 Solar vapor generation Plasmonic effect Optical adjustment Solar selective absorption surface Interfacial evaporation
Atomic level deposition to extend Moore’s law and beyond 认领
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作者 Rong Chen Yi-Cheng Li +2 位作者 Jia-Ming Cai Kun Cao Han-Bo-Ram Lee 《极端制造(英文)》 2020年第2期29-52,共24页
In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitatio... In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitation,and the increase of transistors density on the chip decelerates.Up to now,extreme ultraviolet lithography has been used in some key steps,and it is facing alignment precision and high costs for high-volume manufacturing.Meanwhile,the introduction of new materials and 3D complex structures brings serious challenges for top-down methods.Thus,bottom-up schemes are believed to be necessary methods combined with the top-down processes.In this article,atomic level deposition methods are reviewed and categorized to extend Moore’s law and beyond.Firstly,the deposition brings lateral angstrom resolution to the vertical direction as well as top-down etching,such as double patterning,transfer of nanowires,deposition of nanotubes,and so on.Secondly,various template-assisted selective deposition methods including dielectric templates,inhibitors and correction steps have been utilized for the alignment of 3D complex structures.Higher resolution can be achieved by inherently selective deposition,and the underlying selective mechanism is discussed.Finally,the requirements for higher precision and efficiency manufacturing are also discussed,including the equipment,integration processes,scale-up issues,etc.The article reviews low dimensional manufacturing and integration of 3D complex structures for the extension of Moore’s law in semiconductor fields,and emerging fields including but not limited to energy,catalysis,sensor and biomedicals. 展开更多
关键词 Moore’s law atomic level deposition high resolution selective deposition ALIGNMENT
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Microstructure and mechanical behavior of Inconel 625 alloy processed by selective laser melting at high temperature up to 1000℃ 认领
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作者 Xiao-An Hu Gao-Le Zhao +1 位作者 Fen-Cheng Liu Wei-Xiong Liu 《稀有金属:英文版》 SCIE EI CAS CSCD 2020年第10期1181-1189,共9页
Mechanical behavior of Inconel 625 alloy manufactured by selective laser melting(SLM)was experimentally studied.Tensile tests were performed at various temperatures(20,540,760,815,870,950 and 1000℃).The microstructur... Mechanical behavior of Inconel 625 alloy manufactured by selective laser melting(SLM)was experimentally studied.Tensile tests were performed at various temperatures(20,540,760,815,870,950 and 1000℃).The microstructures and fracture mechanism were investigated using optical microscopy(OM),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The SLM Inconel 625 exhibits excellent plastic deformation at low temperature.However,significant embrittlement for the SLM Inconel 625 was found at elevated temperatures compared to low temperature and traditional forging process.Through microstructure studies,the non-homogenous microstructure is a key factor causing the intergranular cracking mode at elevated temperature.Moreover,carbides were found to form at the grain boundary at elevated temperatures.These carbides could weaken the strength of the grain boundary at elevated temperatures,which decreased the tensile strength and ductility of the alloy processed by SLM. 展开更多
关键词 Nickel-based superalloy Selective laser melting EMBRITTLEMENT High temperature MICROSTRUCTURE
Inbreeding and Inbreeding Depression in a Deciduous Shrub, Magnolia salicifolia, in the Understory of a Japanese Beech Forest 认领
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作者 Kiyoshi Ishida Kazunari Kikuchi Megumi Hayashi 《环境科学与工程:A》 2020年第3期90-97,共8页
Authors conducted pollination experiments and genetic analyses using microsatellite loci for a natural population of a shrub species,Magnolia salicifolia,in a secondary Japanese beech forest in Hakkoda mountains,north... Authors conducted pollination experiments and genetic analyses using microsatellite loci for a natural population of a shrub species,Magnolia salicifolia,in a secondary Japanese beech forest in Hakkoda mountains,northern Japan,to analyze inbreeding and inbreeding depression that involve sexual reproduction and population genetic structure of the species.The pollination experiments revealed that self-fertilization through geitonogamy is possible and that the magnitude of inbreeding depression(δ)at the embryonic stage is substantial(δ=0.42),suggesting that the inbreeding depression due to self-fertilization decreases seed production of the natural population.The genetic analyses showed discrepancy in the level of inbreeding between life history stages:the inbreeding coefficient for the juvenile and adult stage was 0.17 and 0.01,respectively,implying that most of inbred progenies cannot grow to the adult stage in the population,since the cumulative inbreeding depression is severe.These results are consistent with the hypothesis that explains mechanisms causing stable maintenance of severe inbreeding depression in partially inbred populations by focusing on the selective interference among deleterious mutations.It is suggested that some reproductive traits facilitating outcrossing in the species would be attributed to the severe cumulative inbreeding depression. 展开更多
关键词 SHRUB SELF-FERTILIZATION INBREEDING inbreeding depression life history stage selective interference
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Gate length dependent transport properties of in-plane core-shell nanowires with raised contacts 认领
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作者 Alexandre Bucamp Christophe Coinon +4 位作者 David Troadec Sylvie Lepilliet Gilles Patriarche Xavier Wallart Ludovic Desplanque 《纳米研究:英文版》 SCIE EI CAS CSCD 2020年第1期61-66,共6页
Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated transport.In this context,Ⅲ-Ⅴ semiconductor-based nan... Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated transport.In this context,Ⅲ-Ⅴ semiconductor-based nanowires with low electron effective mass and strong spin-orbit coupling are particularly investigated because of their exceptional quantum transport properties and the good electrostatic control they provide.Among the main challenges involved in the processing of these nanodevices are(i)the management of the gate stack which requires ex-situ passivation treatment to reduce the density of traps at the oxide/semiconductor interface,(ii)the ability to get good ohmic contacts for source and drain electrodes and(iii)the scalability and reliability of the process for the fabrication of complex architectures based on nanowire networks.In this paper,we show that selective area molecular beam epitaxy of in-plane InGaAs/InP core-shell nanowires with raised heavily doped source and drain contacts can address these different issues.Electrical characterization of the devices down to 4 K reveals the positive impact of the InP shell on the gate electrostatic control and effective electron mobility.Although comparable to the best reported values for In(Ga)As nanostructures grown on InP,this latter is severely reduced for sub-100 nm channel highlighting remaining issue to reach the ballistic regime. 展开更多
关键词 molecular beam epitaxy core-shell nanowire selective area growth effective electron mobility
Additive manufacturing of composite materials and functionally graded structures using selective heat melting technique 认领
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作者 Kalaimani Markandan Ruijing Lim +6 位作者 Pawan Kumar Kanaujia Ian Seetoh Muhammad Raziq bin Mohd Rosdi Zhi Huey Tey Jun Seng Goh Yee Cheong Lam Changquan Lai 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第12期243-252,共10页
The feasibility of using selective heat melting(SHM) to fabricate composite materials and functionally graded structures was investigated.We report,for the first time,the successful 3 D printing of copper(Cu)-polyethy... The feasibility of using selective heat melting(SHM) to fabricate composite materials and functionally graded structures was investigated.We report,for the first time,the successful 3 D printing of copper(Cu)-polyethylene(PE) composite,iron(Fe)-polyethylene(PE) composite and functionally graded CuO foams using the SHM technique.It was found that a low feed rate,high airflow rate and high airflow temperature were required for efficient delivery of heat from the emitted hot air to the powder bed,so that the PE binder particles can melt and form dense composites with smooth surfaces.The best mechanical properties were exhibited by composites with 80 vol.% PE,as lower PE concentrations led to deficient binding of the metal particles,while higher PE concentrations meant that very few metal particles were available to strengthen the composite.The strength exhibited by Cu-PE composites was comparable to engineering plastics such as polycarbonate,with the added advantage of being electrically conductive.The average conductivity of the samples,0.152±0.28 S/m,was on par with physically crosslinked graphene assemblies.By subjecting a Cu-PE composite,with Cu concentration graded from 10 vol.% to 30 vol.%,to a high temperature debinding and sintering treatment in air,CuO foam with graded porosity can be obtained.This CuO foam was observed to fail in a layer-by-layer manner under mechanical compression,which is a characteristic of functionally graded materials.Our study shows that,compared to existing 3 D printing techniques,SHM can be cheaper,have wider material compatibility,occupy a smaller footprint and potentially induce less residual stresses in the fabricated parts.Therefore,it could be a valuable complement to current additive manufacturing techniques for fabricating mechanically strong composite materials and functionally graded structures. 展开更多
关键词 Selective heat melting Functionally graded materials Additive manufacturing Multimaterial
Sequential transcatheter arterial chemoembolization and portal vein embolization before right hemihepatectomy in patients with hepatocellular carcinoma 认领
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作者 Gil Chun Park Sung Gyu Lee +5 位作者 Young In Yoon Kyu Bo Sung Gi Young Ko Dong Il Gwon Dong Hwan Jung Yong Kyu Jung 《国际肝胆胰疾病杂志:英文版》 SCIE CAS CSCD 2020年第3期244-251,共8页
Background:Recent studies showed that sequential selective transcatheter arterial chemoembolization(TACE)and portal vein embolization(PVE)provided better future liver remnant(FLR)regeneration rate and disease-free sur... Background:Recent studies showed that sequential selective transcatheter arterial chemoembolization(TACE)and portal vein embolization(PVE)provided better future liver remnant(FLR)regeneration rate and disease-free survival following surgery compared with PVE alone.The present study aimed to clarify whether preoperative sequential TACE and PVE before right hemihepatectomy can reduce postoperative hepatocellular carcinoma(HCC)recurrence and improve long-term disease-free and overall survival.Methods:Recurrence and survival outcomes were retrospectively evaluated in 205 patients with HCC who underwent right hemihepatectomy by a single surgeon from November 1993 to November 2017.Patients were divided into four groups according to the procedure performed before the surgery:sequential TACE and PVE(TACE-PVE),PVE-only,TACE-only,or na?ve control groups.The baseline patient and tumor characteristics,postoperative outcomes,recurrence-free survival and overall survival were analyzed.Results:Baseline patient and tumor characteristics upon diagnosis were similar in all four groups,while sequential TACE and PVE were well tolerated.The TACE-PVE group had a higher mean increase in percentage FLR volume compared with that of the PVE-only group(17.46%±6.63%vs.12.14%±5.93%;P=0.001).The TACE-PVE group had significantly better overall and disease-free survival rates compared with the other groups(both P<0.001).Conclusions:Sequential TACE and PVE prior to surgery can be an effective therapeutic strategy for patients with HCC scheduled for major hepatic resection.The active application of preoperative sequential TACE and PVE for HCC would allow more patients with marginal FLR volume to become candidates for major hepatic resection by promoting compensatory FLR hypertrophy without the deterioration of basal hepatic functional reserve or tumor progression. 展开更多
关键词 Sequential selective transcatheter Arterial chemoembolization Portal vein embolization Hepatocellular carcinoma Future liver remnant
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Coating processes towards selective laser sintering of energetic material composites 认领
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作者 Zetu Jiba Walter W.Focke +1 位作者 Lonji Kalombo Moshawe J.Madito 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第2期316-324,共9页
This research aims to contribute to the safe methodology for additive manufacturing(AM)of energetic materials.Coating formulation processes were investigated and evaluated to find a suitable method that may enable sel... This research aims to contribute to the safe methodology for additive manufacturing(AM)of energetic materials.Coating formulation processes were investigated and evaluated to find a suitable method that may enable selective laser sintering(SLS)as the safe method for fabrication of high explosive(HE)compositions.For safety and co nvenie nce reasons,the co ncept demonstration was conducted using inert explosive simulants with properties quasi-similar to the real HE.Coating processes for simulant RDXbased microparticles by means of PCL and 3,4,5-trimethoxybenzaldehyde(as TNT simulant)are reported.These processes were evaluated for uniformity of coating the HE inert simulant particles with binder materials to facilitate the SLS as the adequate binding and fabrication method.Suspension system and single emulsion methods gave required particle near spherical morphology,size and uniform coating.The suspension process appears to be suitable for the SLS of HE mocks and potential formulation methods for active HE composites.The density is estimated to be comparable with the current HE compositions and plastic bonded explosives(PBXs)such as C4 and PE4,produced from traditional methods.The formulation method developed and understanding of the science behind the processes paves the way toward safe SLS of the active HE compositions and may open avenues for further research and development of munitions of the future. 展开更多
关键词 Coating processes ENERGETIC materials Simulants MOCK explosives ADDITIVE MANUFACTURING SELECTIVE laser SINTERING
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On the Probability of Erasure for MIMO-OFDM 认领
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作者 Kasturi Vasudevan A.Phani Kumar Reddy +1 位作者 Gyanesh Kumar Pathak Shivani Singh 《半导体科学与信息器件(英文)》 2020年第1期1-5,共5页
Detecting the presence of a valid signal is an important task of a telecommunication receiver.When the receiver is unable to detect the presence of a valid signal,due to noise and fading,it is referred to as an erasur... Detecting the presence of a valid signal is an important task of a telecommunication receiver.When the receiver is unable to detect the presence of a valid signal,due to noise and fading,it is referred to as an erasure.This work deals with the probability of erasure computation for orthogonal frequency division multiplexed(OFDM)signals used by multiple input multiple output(MIMO)systems.The theoretical results are validated by computer simulations.OFDM is widely used in present day wireless communication systems due to its ability to mitigate intersymbol interference(ISI)caused by frequency selective fading channels.MIMO systems offer the advantage of spatial multiplexing,resulting in increased bit-rate,which is the main requirement of the recent wireless standards like 5G and beyond. 展开更多
关键词 Frequency selective fading ISI Millimeter-wave MIMO OFDM PREAMBLE Probability of erasure
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Selective hydrogenation of acetylene over Pd/CeO2 认领
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作者 Kai Li Tengteng Lyu +1 位作者 Junyi He Ben W.L.Jang 《化学科学与工程前沿:英文版》 SCIE EI CAS CSCD 2020年第6期929-936,共8页
Five hundred ppm Pd/CeO2 catalyst was prepared and evaluated in selective hydrogenation of acetylene in large excess of ethylene since ceria has been recently found to be a reasonable stand-alone catalyst for this rea... Five hundred ppm Pd/CeO2 catalyst was prepared and evaluated in selective hydrogenation of acetylene in large excess of ethylene since ceria has been recently found to be a reasonable stand-alone catalyst for this reaction.Pd/CeO2 catalyst could be activated in situ by the feed gas during reactions and the catalyst without reduction showed much better ethylene selectivity than the reduced one in the high temperature range due to the formation of oxygen vacancies by reduction.Excellent ethylene selectivity of〜100%was obtained in the whole reaction temperature range of 50℃-200℃ for samples calcined at temperatures of 600℃ and 800℃.This could be ascribed to the formation of PdX-Ce1-xO2-y or Pd-O-Ce surface species based on the X-ray diffiaction and X-ray photoelectron spectroscopy results,indicating the strong interaction between palladium and ceria. 展开更多
关键词 selective hydrogenation ACETYLENE Pd/CeO2 strong interaction
Effects of circular beam oscillation technique on formability and solidification behaviour of selective laser melted Inconel 718:From single tracks to cuboid samples 认领
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作者 Huihui Yang Guanyi Jing +2 位作者 Piao Gao Zemin Wang Xiangyou Li 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第16期137-150,共14页
The inherent drawbacks of selective laser melting technique including serious micro-pore and element microsegregation problems destroy the mechanical property of the component.To overcome this problem,a new approach,c... The inherent drawbacks of selective laser melting technique including serious micro-pore and element microsegregation problems destroy the mechanical property of the component.To overcome this problem,a new approach,circular beam oscillation,was successfully applied in the SLMed Inconel 718 samples including single tracks,thin walls and cuboid samples.On one hand,circular beam oscillation reduces the micro-pores in molten pools and cuboid samples,increasing the relative density of the cuboid sample to 99.95%.On the other hand,circular beam oscillation suppresses the element microsegregation,reducing the formation of Laves phases in SLMed Inconel 718 samples.Moreover,circular beam oscillation enhances the<001>texture of thin walls and the<101>texture of cuboid samples.The improvement of formability and microstructure of the SLMed samples with oscillation is closely related to cooling rate,thermal gradient and stirring effect during the solidification process.Therefore,circular beam oscillation shows the possibility to overcome the key bottlenecks of the traditional SLM technology and to realize a further industrial application of SLM technology. 展开更多
关键词 Circular beam oscillation Selective laser melting Inconel 718 Solidification behaviour
Optimization of the heat treatment of additively manufactured Ni-base superalloy IN718 认领
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作者 Benedikt Diepold Nora Vorlaufer +2 位作者 Steffen Neumeier Thomas Gartner Mathias Goken 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2020年第5期640-648,共9页
Additive manufacturing(AM) of Ni-base superalloy components can lead to a significant reduction of weight in aerospace applications. AM of IN718 by selective laser melting results in a very fine dendritic microstructu... Additive manufacturing(AM) of Ni-base superalloy components can lead to a significant reduction of weight in aerospace applications. AM of IN718 by selective laser melting results in a very fine dendritic microstructure with a high dislocation density due to the fast solidification process. The complex phase composition of this alloy, with three different types of precipitates and high residual stresses, necessitates adjustment of the conventional heat treatment for AM parts. To find an optimized heat treatment, the microstructures and mechanical properties of differently solution heat-treated samples were investigated by transmission and scanning electron microscopy, including electron backscatter diffraction, and compression tests. After a solution heat treatment(SHT), the Nb-rich Laves phase dissolves and the dislocation density is reduced, which eliminates the dendritic substructure. SHT at 930 or 954°C leads to the precipitation of the δ-phase, which reduces the volume fraction of the strengthening γ′-and γ′′-phases formed during the subsequent two stage aging treatment. With a higher SHT temperature of 1000°C, where no δ-phase is precipitated, higher γ′ and γ′′ volume fractions are achieved, which results in the optimum strength of all of the solution heat treated conditions. 展开更多
关键词 Ni-base SUPERALLOY selective laser MELTING strengthening mechanism powder BED fusion microstructure
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