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Selective Laser Melting under Variable Ambient Pressure: A Mesoscopic Model and Transport Phenomena

Engineering 2021年第8期7卷 1157-1164页

作者： Renzhi Hu Manlelan Luo Anguo Huang Jiamin Wu Qingsong Wei Shifeng Wen Lichao Zhang Yusheng Shi Dmitry Trushnikov V.Ya.Belenkiy i.Yu.Letyagin K.P.Karunakaran Shengyong Pang State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan 430074China Department of Welding Production Metrologyand Technology of MaterialsPerm National Research Polytechnic UniversityPerm 614990Russia Department of Mechanical Engineering Indian Institute of Technology BombayMumbai 400076India

Recent reports on the selective laser melting(SLM)process under a vacuum or low ambient pressure have shown fewer defects and better surface quality of the as-printed *** the physical process of SLM in a vacuum has been investigated by high-speed imaging,the underlying mechanisms governing the heat transfer and molten flow are still not well ***,we first developed a mesoscopic model of SLM under variable ambient pressure based on our recent laser-welding *** simulated the transport phenomena of SLM 316L stainless steel powders under atmospheric and 100 Pa ambient *** typical process parameters(laser power:200W;scanning speed:2m∙s^(-1);powder diameter:27 lm),the average surface temperature of the cavity approached 2800 K under atmospheric pressure,while it came close to 2300 K under 100 Pa *** vigorous fluid flow(average speed:4m∙s^(-1))was observed under 100 Pa ambient pressure,because the pressure difference between the evaporation-induced surface pressure and the ambient pressure was relatively larger and drives the flow under lower *** was also shown that there are periodical ripple flows(period:14ls)affecting the surface roughness of the as-printed ***,the molten flow was shown to be laminar because the Reynolds number is less than 400 and is far below the critical value of turbulence;thus,the viscous dissipation is *** was demonstrated that under a vacuum or lower ambient pressure,the ripple flow can be dissipated more easily by the viscous effect because the trajectory length of the ripple is longer;thus,the surface quality of the tracks is *** summarize,our model elucidates the physical mechanisms of the interesting transport phenomena that have been observed in independent experimental studies of the SLM process under variable ambient pressure,which could be a powerful tool for optimizing the SLM process in the future.

关键词： Selective laser melting Mesoscopic model Ambient pressure Transport phenomena

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PROMOTiNG EFFECT OF RARE EARTH ADDiTiVES ON Ni-BASED METHANATiON CATALYSTS

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Journal of Energy Chemistry 1994年第4期 468-478页

作者： LiU Xin-Hua Li Xiao-Li M1AO Yin CAO Pei-Hua HU Rui-ShengDepartment of Chemistry, Neimenggu University Huhehaote, Neimenggu 010021DiNG Yu-QingScieittifk’ Research huititutf of i’etro/r/tm i’hp/oratMii and 100083

The promoting effect of rare earth oxides on Ni- based methanationcatalyst was investigated by temperature programmed desorption （TPD） andtemperature programmed surface reaction （TPSR ） with the help of X-rayphoto-electrospectroscopy （XPS） and infrared spectroscopy （iR）. The additionof rare earth oxides not only improved the dispersion of the active component ofthe catalyst, but also changed the species and properties of the surface activesites of the catalyst. increased low energy adsorption sites and retainedhydrogen. promoted the disproportionation and decomposition of CO. Somerare earth oxides enriched on the surface after reduction and made Ni2pbinding energy lower.

关键词： TPD La TPSR Ni PROMOTiNG EFFECT OF RARE EARTH ADDiTiVES ON Ni-BASED METHANATiON CATALYSTS

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不同助熔剂体系下Ga_3PO_7单晶的生长与表征(英文)

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硅酸盐学报 2011年第8期39卷 1339-1343页

作者：郭永解李静王继扬韩树娟王永政 BOUGHTON Robert i 山东大学晶体材料国家重点实验室中国济南250100 Department of Physics and Astronomy Green State University OH 43403 USA

在X2CO3–MoO3(X=Li,K)助熔剂体系下,采用顶部籽晶缓冷法生长出厘米级磷酸三镓(Ga3PO7)晶体。实验结果表明:X2CO3–MoO3助熔剂适合Ga3PO7单晶的生长。通过测量Ga3PO7单晶的紫外–近红外光谱和中红外光谱研究了其基本光学性能。在K2CO3–... 详细信息

在X2CO3–MoO3(X=Li,K)助熔剂体系下,采用顶部籽晶缓冷法生长出厘米级磷酸三镓(Ga3PO7)晶体。实验结果表明:X2CO3–MoO3助熔剂适合Ga3PO7单晶的生长。通过测量Ga3PO7单晶的紫外–近红外光谱和中红外光谱研究了其基本光学性能。在K2CO3–MoO3助熔剂体系下,生长的Ga3PO7晶体(101)晶面的透过率达到89%。热学性能测试表明:Ga3PO7晶体具有高的温度稳定性(在K2CO3–MoO3助熔剂体系下高达1 621.15 K),Ga3PO7晶体的导热性良好,且各向异性不明显,有利于其应用。从Li2CO3–MoO3和K2CO3–MoO3两种助熔剂体系中生长的Ga3PO7晶体,其基本性能无明显区别。

关键词：磷酸三镓单晶助熔剂体系光学性能热学性能顶部籽晶缓冷法

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En bloc resection concept for endoscopic endonasal nasopharyngectomy： surgical anatomy and outcome

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Chinese Medical Journal 2014年第16期127卷 2934-2939页

作者： Hsu Ning-i Shen Ping-hung Chao Siew-shuen Ong Yew-kwang Li Cho-shun Department of Otolaryngology Kuang-Tien General HospitalTaichung Taiwan China Department of Biotechnology Hung-Kuang University TaichungTaiwan China Department of Otolaryngology Head and Neck Surgery National University Hospital Singapore Department of Neurosurgery Chung-Shan Medical UniversityHospital Taichung Taiwan China School of Medicine Chung-Shan Medical University TaichungTaiwan China

Background Nasopharyngeal carcinoma （NPC） patients have a 19%-56% locoregional recurrence rate after primary *** those recurrent NPC （rNPC） patients,re-irradiation may cause some *** recent years,endoscopic endonasal nasopharyngectomy （EEN） has become a surgical option for rNPC *** we introduce the concept of en bloc excision （EBE） technique for EEN,including the surgical technique and clinical *** A retrospective study was conducted covering September 2009 to May 2013,involving the collection of iocoregional rNPC cases from two institutions （Kuang-Tien General Hospital （KTGH） in Taiwan and National University Health System （NUHS） in Singapore）.These patients failed prior therapy and then underwent *** reported the 2-year overall survival rate,the 2-year disease-free survival rate,and related *** Nine patients （five from KTGH and four from NUHS） completed this study,with five,two,and two patients of recurrence tumors （rT1）,rT2,and rT3,*** mean age was 46.4 years （range 32-63）; the mean follow-up period was 24.9 months （range 10-45）.The 2-year survival rate and the 2-year disease-free rate were 100% and 80%,respectively,in five *** significant complications or cases of mortality *** The EBE concept of EEN is suitable for early rT1 and has relatively encouraging short-term *** selected rT2,careful EBE can be performed by expanding the surgical field.A clear view of the internal carotid arteryrelated anatomy is *** the future,more series may be needed to determine the role of EEN in rNPC patients.

关键词： nasopharyngeal carcinoma nasopharyngectomy endoscopy tensor palatini muscle levator palatini muscle

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Different cutoff values of methacholine bronchial provocation test depending on age in children with asthma

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World Journal of Pediatrics 2017年第5期13卷 439-445页

作者： Eun Lee Young-Ho Kim Seungbong Han Song-i Yang Young-Ho Jung Ju-Hee Seo Hyo-Bin Kim So Yeon Lee Ji-Won Kwon Soo-Jong Hong Department of Pediatrics Chonnam National University HospitalGwangjuKorea Department of Pediatrics Gyeongsang National University Changwon HospitalChangwonKorea Department of Applied Statistics Gachon UniversitySeongnamKorea Department of Pediatrics Hallym University Sacred Heart HospitalAnyangKorea Department of Pediatrics Bundang CHA Medical CenterCHA University School of MedicineSeongnamKorea Department of Pediatrics Dankook University College of MedicineCheonanKorea Department of Pediatrics Inje University Sanggye Paik HospitalSeoulKorea Department of Pediatrics Childhood Asthma Atopy CenterResearch Center for Standardization of Allergic DiseasesAsan Medical CenterUniversity of Ulsan College of MedicineSeoulKorea Department of Pediatrics Seoul National University Bundang HospitalSeongnamKorea

Background:Bronchial hyperresponsiveness (BHR) is a fundamental pathophysiological characteristic of *** several factors such as airway caliber can affect BHR,no study has established age-dependent cutoff values of BHR to methacholine for the diagnosis of asthma in *** investigated the cutoff values of the methacholine challenge test (MCT) in the diagnosis of asthma according to ***:A total of 2383 individuals aged from 6 to 15 years old were included in this *** using the five-breath technique were performed in 350 children with suspected asthma based on symptoms by pediatric allergists and in 2033 healthy children from a general population-based *** determined the provocative concentration of methacholine producing a 20% decrease in forced expiratory volume in 1 second from baseline (PC20).A modified Korean version of the international Study of Asthma and Allergies in Childhood questionnaire was used to distinguish asthmatics and healthy *** characteristic curve analysis was used to assess the cutoff value of PC20 for the diagnosis of ***:Cutoff values of methacholine PC20,which provided the best combination of diagnostic sensitivity and specificity,showed an increasing pattern with age:5.8,9.1,11.8,12.6,14.9,21.7,23.3,21.1,21.1,and 24.6 mg/mL at ages 6,7,8,9,10,11,12,13,14,and 15 years,***:The application of different cutoff values of methacholine PC20 depending on age might be a practical modification for the diagnosis of asthma in children and adolescents with asthmatic symptoms.

关键词： asthma bronchial hyperresponsiveness cutoff value receiver-operator characteristics

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implications of excreta uric acid concentrations in broilers offered reduced crude protein diets and dietary glycine requirements for uric acid synthesis

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Animal Nutrition 2021年第4期7卷 939-946页

作者： Peter H.Selle David i.Cantor Leon R.McQuade Bernard V.Mcinerney Juliano Cesar de Paula Dorigam Shemil P.Macelline Peter V.Chrystal Sonia Y.Liu Poultry Research Foundation within The University of Sydney CamdenNSW 2570Australia Sydney School of Veterinary Science The University of SydneySydneyNSW 2006Australia Australian Proteome Analysis Facility Macquarie UniversitySydneyNSW 2109Australia Evonik Nutrition and Care GmbH Hanau-Wolfgang 63547Germany School of Life and Environmental Sciences Faculty of ScienceThe University of SydneySydneyNSW 2006Australia Baiada Poultry Pty Limited Pendle HillNSW 2145Australia

in a previous experiment,male Ross 308 broiler chickens were offered dietary treatments with 3 levels of crude protein(222,193,165 g/kg)and 3 feed grains(ground maize,ground wheat,whole wheat)from 7 to 35 d ***-based diets supported superior growth performance in comparison to wheatbased *** acid concentrations in excreta were retrospectively determined and related to total nitrogen(N)excreta *** acid concentrations ranged from 28.5 to 69.4 mg/g and proportions of uric acid-N to total excreta-N ranged from 27.4%to 42.6%in broiler chickens offered the 3×3 factorial array of dietary *** of uric acid-N to total N in excreta in birds offered the165 g/kg CP,maize-based diet were significantly lower by 10.6 percentage units(27.4%versus 38.0%;P=0.00057)than their wheat-based *** excreta analysed had been collected from 35 to37 d post-hatch when feed intakes and excreta outputs were *** were linear relationships between proportions of uric acid-N to total N in excreta in birds offered the three 165 g/kg CP diets with weight gain(r=-0.587;P=0.010),feed intake(r=-0.526;P=0.025)and feed conversion ratios(r=0.635;P=0.005).The possibility that increasing uric acid-N proportions in excreta is indicative of excessive ammonia accumulations compromising growth performance is *** mean proportion of dietary glycine involved in uric acid excretion was 49.2%across all dietary treatments but ranged from 25.0%to 80.9%.Thus,the appropriate amount of dietary glycine is variable and largely dependent on the volume of uric acid synthesised and excreted.

关键词： Ammonia Broiler chicken Glycine Reduced crude protein diet Uric acid

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Dynamical Modeling of the Nuclear Fission Process at Low Excitation Energies

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Journal of Applied Mathematics and Physics 2014年第5期2卷 27-31页

作者： i. i. Gontchar M. V. Chushnyakova E. P. Oskin E. G. Demina Physics and Chemistry Department Omsk State Transport University Omsk Russia Physics Department Omsk State Technical University Omsk Russia

Two recipes for modeling the dynamics of the nuclear fission process are known in literature. The underlying equations contain the driving, dissipative, and random forces. The two recipes are mostly different in the prescriptions for the driving force. in this work we carefully compare these driving forces and the resulting fission rates. it turns out that the rates may be very close or strongly different depending on the value the shell correction to the nuclear deformation energy. We give arguments in favor of one of the recipes.

关键词： Nuclear Fission Dynamical Modeling Stochastic Differential Equations Fermi Gas Model

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Challenging Nanopores with Analyte Scope and Environment

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Journal of Analysis and Testing 2019年第1期3卷 61-79页

作者： Buddini i.Karawdeniya Y.M.Nuwan D.Y.Bandara Jonathan W.Nichols Robert B.Chevalier James T.Hagan Jason R.Dwyer Department of Chemistry University of Rhode IslandRichard E.Beaupre Center for Chemical and Forensic Sciences140 Flagg Rd.KingstonRI 02881USA Present Address:Department of Mechanical Engineering Lyle School of EngineeringSouthern Methodist UniversityDallasTX 75275USA Present Address:Nova Biomedical 200 Prospect StreetWalthamMA 02454-9141USA

Nanopores are nanofluidic channels formed through thin membranes that can deliver standout single-molecule and single-particle sensing *** targets include small molecules and nanoparticles,and the DNA,protein,and glycan biopolymers underpinning genomics,proteomics,and ***-notably even in the simplest implementation,resistive-pulse sensing-does not inherently require sample labeling and,thus,offers the potential for general sensing util-ity combined with the prospective benefits of reduced sample processing requirements.A key pursuit for biopolymer sens-ing is the characterization of monomer *** review article will provide an overview of the use of nanopores for general chemical sensing and-omics-related applications,*** broad analyte scope provides fertile ground for a discussion of principles governing nanopore sensing and considerations useful for guiding nanopore *** nanopores to be effective in the face of broad analyte scope,stringent requirements on analytical performance must be met within the particular analyte class without sacrificing the operational flexibility necessary to be responsive across classes presenting very different physical and chemical *** sample-driven challenges provide a unifying framework for discussing aspects of nanopore fabrication,properties,and integration;sensing paradigms,performance,and prospects;fundamental electrokinetic and interfacial phenomena;and practical challenges facing the use and further development of nanopore devices.

关键词： Nanopore Single-molecule sensing Nanofluidics Point-of-care Silicon nitride Resistive pulse Wearable sensors Quality assurance

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Biomedical applications of Jones-matrix tomography to polycrystalline films of biological fuids

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Journal of innovative Optical Health Sciences 2019年第6期12卷 72-84页

作者： V.A.Ushenko A.Yu.Sdobnov W.D.Mishalov A.V.Dubolazov O.V.Olar V.T.Bachinskyi A.G.Ushenko Yu.A.Ushenko O.Ya.Wanchuliak i.Meglinsk Chernivtsi National University 2 Kotsiubynskyi St. Chernivtsi58012 Ukraine Faculty of information Technology and Electrical Engineering University of Oulu Oulu 90570Finland Shupyk National Medical Academy of Postgraduate Education 9 Dorogozhytska St.Kyiv04112 Ukraine Bukovinian State Medical University 3 Theatral Sq. Chernivtsi58000 Ukraine interdisciplinary Laboratory of Biophotonics National Research Tomsk State University Tomsk 634050 Russia institute of Engineering Physics for Biomedicine(PhysBio)National Research Nuclear University"MEPhi"Moscow 15409 Russia Aston institute of Materials Research School of Engineering and Applied Science Aston University BirminghamB47ETUK School of Life and Health Sciences Aston University BirminghamB47ETUK

Algorithms for reconstruction of linear and circular birefringence-dichroism of optically thin anisotropic biological layers are *** technique of Jones matrix tomography of poly-crystalline films of biological fuids of various human organs has been developed and experimentally *** coordinate distributions of phase and amplitude anisotropy of bile films and synovial fuid taken from the knee joint are determined and statistically ***(statistical moments of 3rd and 4th orders)of differential diagnostics of early stages of cholelithiasis and septic arthritis of the knee joint with excellent balanced accuracy were *** on the diagnostic fficiency of the Jones matrix tomography method for polyerystalline plasma(liver disease),urine(albuminuria)and cytological smears(cervical cancer)are presented.

关键词： Polarization Fourier optics and signal processing imaging systems medical and biological imnaging

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Effect of Combined Use of Brackish Water and Nitrogen Fertilizer on Biomass and Sugar Yield of Sweet Sorghum

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Pedosphere 2012年第6期22卷 785-794页

作者： T.B.RAMOS N.L.CASTANHEiRA M.C.GONALVES M.L.FERNANDES M.i.JANURiO M.E.LOURENO F.P.PiRES J.C.MARTiNS CEER-Biosystems Engineering Institute of Agronomy Technical University of Lisbon Tapada da Ajuda 1349-017 Lisbon (Portugal) Estao Agronómica Nacional L-INIA Instituto Nacional de Recursos Biológicos Quinta do Marquês Av. República 2784-505 Oeiras (Portugal) Departamento de Fitotecnia Instituto de Ci encias Agrrias e Ambientais Mediterrnicas Universidade de vora Apartado 94 7002-554 vora (Portugal)

Soil salinization and non-point source pollution are among the most important and widespread environmental problems in European Mediterranean regions. Sweet sorghum （Sorghum bicolor （L.） Moench var. saccharatum） is a moderate to high salinity tolerant crop with low water and nutrient needs, seen as an alternative to grow in the water scarce regions. A three-year multifactorial study was conducted in southern Portugal to evaluate the combined effects of saline water and nitrogen application on the dry biomass （total, stems, and leaves）, sugar content （total reducing sugars and sucrose eontents） and sugar yield （here defined as the product of total reducing sugars and stems dry biomass） functions of sweet sorghum. Sorghum dry biomass and sugar yield showed diminishing returns for each incremental change of nitrogen. The use of saline irrigation waters also led to yield reduction. Exception was sucrose content which increased with increasing levels of sodium in the soil. Nitrogen need decreased as the amount of sodium applied increased. Stem dry biomass, sucrose content, and sugar yield progressively increased with progress in the experiment. The effect could be attributed to the increase of the amount of irrigation applied throughout the years, thus increasing the leaching fraction which promoted salt leaching from the root zone, reduced the salinity stress, increased plant transpiration, nitrogen uptake and biomass yield.

关键词： Mediterranean conditions non-point source pollution salinity sweet sorghum yield functions

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