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GSTARS computer models and their applications, part I:theoretical development

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International Journal of Sediment Research 2008年第3期23卷 197-211页

作者： Chih Ted YANG francisco J. M. simes Borland Prof. of Water Resources and Director of Hydroscience and Training Center Department of Civil and Environmental Engineering Colorado State University Fort Collins CO 80523-1372 U. S. A. Research Hydrologist US Geological Survey Geomorphology and Sediment Transport Laboratory 4620 Technology Drive Suite 400 Golden CO 80403 U. S. A.

GSTARS is a series of computer models developed by the U.S. Bureau of Reclamation for alluvial river and reservoir sedimentation studies while the authors were employed by that agency. The first version of GSTARS was released in 1986 using Fortran IV for mainframe computers. GSTARS 2.0 was released in 1998 for personal computer application with most of the code in the original GSTARS revised, improved, and expanded using Fortran IV/77. GSTARS 2.1 is an improved and revised GSTARS 2.0 with graphical user interface. The unique features of all GSTARS models are the conjunctive use of the stream tube concept and of the minimum stream power theory. The application of minimum stream power theory allows the determination of optimum channel geometry with variable channel width and cross-sectional shape. The use of the stream tube concept enables the simulation of river hydraulics using one-dimensional numerical solutions to obtain a semi-two-dimensional presentation of the hydraulic conditions along and across an alluvial channel. According to the stream tube concept, no water or sediment particles can cross the walls of stream tubes, which is valid for many natural rivers. At and near sharp bends, however, sediment particles may cross the boundaries of stream tubes. GSTARS3, based on FORTRAN 90/95, addresses this phenomenon and further expands the capabilities of GSTARS 2.1 for cohesive and non-cohesive sediment transport in rivers and reservoirs. This paper presents the concepts, methods, and techniques used to develop the GSTARS series of computer models, especially GSTARS3.

关键词： Numerical modeling Sediment transport Backwater computations Stream tubes Stream power minimization

Oxidative coupling of methane over LaAlO3 perovskite catalysts prepared by a co-precipitation method: Effect of co-precipitation pH value

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Journal of Energy Chemistry 2019年第8期28卷 1-8,I0001页

作者： Yujin sim Jihoon Yoo Jeong-Myeong Ha Ji Chul Jung Department of Chemical Engineering Myongji UniversityYongin 17058 Republic of Korea Clean Energy Research Center Korea Institute of Science and TechnologySeoul 02792 Republic of Korea

Oxidative coupling of methane(OCM) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 *** the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCM reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCM.

关键词： LaAlO3 Perovskite Oxidative coupling of methane co-precipitation pH value

cost projections for microwave plasma co production using renewable energy

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Journal of Energy Chemistry 2022年第8期31卷 507-513,I0014页

作者： Remko J.Detz Bob van der Zwaan Netherlands Organisation for Applied Scientific Research(TNO) Amsterdam 1043 NTThe Netherlands Faculty of Science(HIMS and IAS) University of AmsterdamAmsterdam 1090 GDThe Netherlands School of Advanced International Studies(SAIS) Johns Hopkins UniversityBologna 40126Italy

Successful deployment of renewable fuel production requires substantial cost reduction along the entire value chain of the underlying manufacturing *** improve their performance,renewable fuel production technologies should follow a cost-reducing learning *** this article,we adopt recent evidence that learning-by-doing is directly influenced by the technology unit size and explore three scenarios for microwave plasma co_(2)conversion in which the learning rate varies between 10%,15%,and 20%.Our projections reveal that the total investments required to deploy this co_(2)conversion technology at an exajoule scale decline from 83 down to 23 billion euros under a 10%increase in the value of the learning *** co_(2) production costs in 2050 amount to 247–346€(2019)/t co_(2),in which the range is determined by the value of the learning *** under substantial learning until 2050 the levelized co production cost is unlikely to become competitive with conventional natural gas-based co_(2) production processes,except when a co_(2)tax is applied of up to 150€(2019)/t co_(2).To optimally exploit effects of learning-by-doing,we recommend developing several co production technologies simultaneously with multiple unit sizes,so as to improve the chance of ultimately selecting the process with the highest learning rate.

关键词： co_(2)utilization Synthetic fuels Renewable chemicals Learning curves Unit size

The lymphocyte scavenger receptor CD5 plays a nonredundant role in fungal infection

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Cellular & Molecular Immunology 2021年第2期18卷 498-500页

作者： María Velasco-de-Andrés Cristina Català Sergi Casadó-Llombart Inês simões Oscar Zaragoza esther Carreras francisco Lozano Immunoreceptors of the Innate and Adaptive System Institut d’Investigacions Biomèdiques August Pi i Sunyer08036BarcelonaSpain Mycology Reference Laboratory National Centre for MicrobiologyInstituto de Salud Carlos III28220MajadahondaSpain Servei d’Immunologia Centre de Diagnòstic BiomèdicHospital Clínic de Barcelona08036BarcelonaSpain Departament de Biomedicina Universitat de Barcelona08036BarcelonaSpain

Invasive fungal diseases(IFD)impact morbidity,mortality,hospital stay and healthcare costs in critically ill patients,constituting an unmet medical need.1 Pathogenic fungi rarely cause IFD in immunocompetent individuals but become life-threatening in cases of immunodeficiency,young infants,disrupted mucosal barriers or polyantibiotic therapy,highlighting the role of immune surveillance in IFD control.^(2)

关键词： fungal mortality diseases

Alpha-1 antitrypsin deficiency and Pi^(*)Z allele as important co-factors in the development of liver fibrosis

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World Journal of Hepatology 2024年第8期16卷 1099-1110页

作者： Ana Isabel Ferreira Catarina Guimarães Vitor Macedo Silva Sofia Xavier Joana Magalhães Josécotter Department of Gastroenterology Hospital da Senhora da Oliveira-GuimarãesGuimarães 4835-044Portugal Life and Health Sciences Research Institute School of MedicineUniversity of MinhoBraga 4710-057Portugal Life and Health Sciences Research Institute/3B’s PT Government Associate LaboratoryBraga 4710-057Portugal Department of Pulmonology Hospital Senhora da Oliveira-GuimarãesGuimarães 4835-044Portugal

BACKGROUND Alpha-1 antitrypsin deficiency(AATD)is a codominant autosomal hereditary condition that predisposes patients to the development of lung and/or liver disease,and Pi*Z allele is the most clinically relevant *** To evaluate the impact of clinical parameters and AATD phenotypes,particularly the Pi*Z allele,in liver *** Cross-sectional cohort study including consecutive patients with AATD followed in Pulmonology or Hepatology *** Included 69 patients,49.3%had Pi*MZ phenotype and 10.1%Pi**** age≥55 years,age at diagnosis≥41 years and AAT at diagnosiscoholic fatty liver disease fibrosis score(NFS)not excluding advanced fibrosis[area under the curve(AUC)=0.840,Pderate to advanced fibrosis(AUC=0.831,Pes mellitus(DM),dyslipidaemia,metabolic syndrome,and regular alcohol consumption were more likely to have a NFS not excluding advanced fibrosis(Pes more likely to have liver stiffness measurement≥7.1 kPa(P=0.040).coNCLUSION Risk factors for liver disease in AATD included an age≥50 years,age at diagnosis≥41 years,metabolic risk factors,regular alcohol consumption,at least one Pi*Z allele,and AAT value at diagnosisconsultation.

关键词： Alpha-1 antitrypsin deficiency Liver fibrosis Nonalcoholic fatty liver disease fibrosis score Fibrosis-4 index Liver stiffness measurement

Infrared spectroscopy analyses of air-CH_4 or air-co gas flows interacting with polycrystalline CeO_2, La_2O_3 and Lu_2O_3 oxides

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Journal of Rare Earths 2012年第8期30卷 835-841页

作者： Bahcine BAKIZ Lamia BOURJA Abdeljalil BENLHACHEMI frédéric GUINNETON Madjid ARAB Jean-Raymond GAVARRI Institute Materials Microelectronics & Nanosciences of Provence UMR CNRS 6242 University SOUTH Toulon-Var Laboratory Materials & Environment Faculty of Sciences University Ibn Zohr

A comparative study of reactivity between air-CH4 or air-co gas flows and CeO2, La2O3 and Lu2O3 rare earth oxides was per- formed using Fourier transform infrared spectroscopy analyses of co2 gas resulted from the conversion of CH4 or co gases. Polyerystalline samples of CeO2, La2O3 and Lu2O3 were first prepared by specific precipitation methods followed by low temperature calcination process. In the case of Lu2O3 oxide, a new specific route was proposed. Crystallite dimensions were determined by X-ray diffraction and transmission electron microscopy analyses. Morphologies were characterized using scanning electron microscopy. Specific surface areas were determined from Bnmauer-Emmett-Teller （BET） technique. Using infrared spectroscopy analyses, the conversion rates of CH4 or co into co2 were de- termined from the evolutions of co2 vibrational band intensities, as a function of time and temperature. It was dearly established that, despite its low specific surface, the Lu2O3 oxide presented the highest capacity of conversion of CH4 or co into co2.

关键词： lutetium oxide rare earth oxides elaboration gas solid interactions infrared spectroscopy

Topical ocular administration of DPP-Ⅳ inhibitors:a new approach for treating diabetes-induced retinal neurodegeneration

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Neural Regeneration Research 2024年第4期19卷 713-714页

作者： Rafael simó Cristina Hernández Diabetes and Metabolism Research Unit Vall d’Hebron Research Institute(VHIR) Department of Medicine Autonomous University of Barcelona Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas(CIBERDEM) Instituto de Salud CarlosⅢ(ICSⅢ)

Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable *** fact,the American Diabetes Association has defined DR as a highly specific neurovascular complication(Solomon et al.,2017).Therefore,it is no longer acceptable to consider DR as merely a microvascular *** this regard,the term diabetic retinal disease(DRD)has been proposed as a broader term comprising microangiopathy and ***,there are currently no treatments available that directly target the neurodegenerative changes of *** paper will give new insights into the translational research in this field with particular emphasis on glucagon-like peptide 1/dipeptidyl peptidase IV(GLP-1/DPP-IV)inhibitors.

关键词： neurodegeneration ocular insight

computer simulation of W-C-co-V system diffusion couples

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Rare Metals 2007年第5期26卷 492-497页

作者： HE Yanlin LI Lin HUANG Shuigen Jef Vleugels Omer Van der Biest School of Material Science ＆ Engineering Shanghai University Shanghai 200072 China Department of Metallurgy and Materials Engineering Katholieke Universiteit Leuven Kasteelpark Arenberg 44 Heverlee B-3001 Belgium

Diffusion couples,WC/co-1at.%C,V8C7/co,and WC/co-0.3wt.%V8C7 were constructed and annealed at temperatures ranging from 1100 to 1300℃. The concentration profile of V and W atoms in these couples were measured by EPMA. Aided by Thermo-calc ＆ DICTRA software package,the concentration profiles of W and V in established diffusion couples were calculated by the moving boundary model according to revised dynamic parameters and MOB database,respectively. Then the concentration profile of W in co binder during sintering WC-co cemented carbide was simulated by the Cell model. It can provide reference for composition and sintering process design of cemented carbides with high performance. Meanwhile,the validity of revised dynamic parameters of the W-C-co-V system is verified by the comparison of experimental and simulated results.

关键词： material science W-C-co-V system Thermo-calc and DICTRA software package dynamic parameters

Sintering of WC-co powder with nanocrystalline WC by spark plasma sintering

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Rare Metals 2006年第3期25卷 246-252页

作者： WANG Xingqing XIE Yingfang GUO Hailiang O.Van der Biest J.Vleugels School of Materials Science and Engineering Shanghai University Shanghai 200072 China Materials Engineering Faculty of Engineering Katholikeke Universiteit Leuven Leuven 3000 Belgium

A 92WC-8co powder mixture with 33 nm WC grains was prepared by strengthening ball milling and was then sintered by spark plasma sintering （SPS） at 1000-1200℃ for 5-18 rain under 10-25 kN, respectively. Movement of the position of low punch shown shrinkage of the sintered body began above 800℃. The shrinkage slowly rose as the temperature rose from 800 to 1000℃ and then quickly rose at above 1000℃ and then gradually rose at above 1150℃. The densities of the samples increased with an increase in sintering temperature, rapidly below 1100℃, and then gradually above 1100℃. WC grains grow gradually with increasing sintering temperature. The powder was sintered to near full density at 1100℃ for 5 rain under 10 kN. The best result of the sample with 275 nm WC grains and no pores was obtained at 1150℃ under 10 kN for 5 rain. The research found the graphite die had a function of carburization, which could compensate the sintered body for the lack of carbon, and had the normal microstructure.

关键词： nanocrystalline cemented carbide spark plasma sintering low temperature sintering strengthening ball milling