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Performance and Flow Condition of Small-Sized Axial Fan and Adoption of Contra-Rotating Rotors

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journal of thermal Science 2010年第1期19卷 1-6页

作者： t.Shigemitsu j.Fukutomi Y.Okabe Institute of technology and Science The University of Tokushima2-1 Minamijyosanjima-choTokushima 770-8506JAPAN Graduate School of Advanced technology and Science The University of Tokushima2-1 Minamijyosanjima-choTokushima 770-8506JAPAN

Small-sized axial fans are used as air coolers for electric *** there is a strong demand for higher power of fans according to the increase of quantity of heat from electric ***,higher rotational speed design is conducted,although it causes the deterioration of the efficiency and the increase of *** the adoption of contra-rotating rotors for the small-sized axial fan is proposed for the improvement of the *** the present paper,the performance and the internal flow condition of the small-sized axial fan are shown as a first step of the research for the contra-rotating small-sized axial fan and the important points to apply contra-rotating rotors to the small-sized axial fan are ***,the numerical flow analysis is conducted to investigate the performance of the contra-rotating small-sized axial fan and internal flow conditions and pressure distributions are clarified and the effect of contra-rotating rotors is considered.

关键词： Small-sized axial fan Contra-rotating rotors Numerical analysis Performance Internal flow

the Covid-19 outbreak in Spain.A simple dynamics model,some lessons,and a theoretical framework for control response

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Infectious Disease Modelling 2020年第1期5卷 652-669页

作者： antonio Guirao Department of Physics Universidad de MurciaEd.CIOyNCampus de Espinardo30100MurciaSpain

Spain is among the countries worst hit by the Covid-19 pandemic,with one of the highest rate of infections and deaths per million *** positive was reported on late january *** March,with 7,000 confirmed cases,nationwide lockdown was *** May the epidemic was stabilized and government eased *** we model the dynamics of the epidemic in Spain over the whole span,and study the effectiveness of control *** model is also applied to Italy and *** propose formulas to easily estimate the size of the outbreak and the benefit of early intervention.A susceptibleinfectious-recovered(SIR)model was used to simulate the *** growth and transmission rates,doubling time,and reproductive number were estimated by leastmean-square fitting of daily ***-series data were obtained from official government *** forecasted the epidemic curve after lockdown under different effectiveness scenarios,and nowcasted the trend by moving average sliding *** growth expressions were *** progression remained under the early growth *** basic reproductive number in Spain was 2.5±0.1(95%CI 2.3 e2.7),and the doubling time was 2.8±0.1 days(95%CI 2.6e3.0).Slight variations in measures effectiveness produce a large divergence in the epidemic *** effectiveness in Spain was 68%,above control threshold(60%).During lockdown the reproductive number dropped to an average of 0.81±0.02(95%CI 0.77e0.85).Estimated epidemic size is about 300,000 cases.A 7-days advance of measures yields a reduction to 38%.the dynamics in Spain is similar to other *** lockdown measures must be adopted if not compensated by rapid detection and isolation of patients,and even a slight relaxation would raise the reproductive number above *** calculations allow anticipating the size of the epidemic based on when measures are taken and their *** acted *** measures must be implemented immedi

关键词： Covid-19 SARS-CoV-2 Epidemic Control Prevention Model

Inflammatory status in human hepatic cirrhosis

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World journal of Gastroenterology 2015年第41期21卷 11522-11541页

作者： María Martínez-Esparza María tristán-Manzano antonio j Ruiz-Alcaraz Pilar García-Penarrubia Departamento de Bioquímica Biología Molecular (B) e Inmunología Facultad de Medicina IMIB Regional Campus of International Excellence "Campus Mare Nostrum" Universidad de Murcia

this review focuses on new findings about the inflammatory status involved in the development of human liver cirrhosis induced by the two main causes, hepatitis C virus(HCV) infection and chronic alcohol abuse, avoiding results obtained from animal models. When liver is faced to a persistent and/or intense local damage the maintained inflammatory response gives rise to a progressive replacement of normal hepatic tissue by non-functional fibrotic scar. the imbalance between tissue regeneration and fibrosis will determine the outcome toward health recovery or hepatic cirrhosis. In all cases progression toward liver cirrhosis is caused by a dysregulation of mechanisms that govern the balance between activation/homeostasis of the immune system. Detecting differences between the inflammatory status in HCV-induced vs alcoholinduced cirrhosis could be useful to identify specific targets for preventive and therapeutic intervention in each case. thus, although survival of patients with alcoholic cirrhosis seems to be similar to that of patients with HCV-related cirrhosis(HCV-C), there are important differences in the altered cellular and molecular mechanisms implicated in the progression toward human liver cirrhosis. the predominant features of HCV-C are more related with those that allow viral evasion of the immune defenses, especially although not exclusively, inhibition of interferons secretion, natural killer cells activation and t cell-mediated cytotoxicity. On the contrary, the inflammatory status of alcohol-induced cirrhosis is determined by the combined effect of direct hepatotoxicity of ethanol metabolites and increases of the intestinal permeability, allowing bacteria and bacterial products translocation, into the portal circulation, mesenteric lymph nodes and peritoneal cavity. this phenomenon generates a stronger pro-inflammatory response compared withHCV-related cirrhosis. Hence, therapeutic intervention in HCV-related cirrhosis must be mainly focused to counter

关键词： Inflammation Macrophages Cirrhosis Alcohol Hepatitis C virus Cytokines Liver

Grain Size Distribution and Interfacial Heat transfer Coefficient during Solidification of Magnesium Alloys Using High Pressure Die Casting Process

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journal of Materials Science & technology 2018年第2期34卷 324-334页

作者： P. Sharifi j. jamali K. Sadayappan j.t. Wood Western University London Ontario Canada Canmet MAtERIALS Hamilton ON Canada

the objective of this study is to predict grain size and heat transfer coefficient at the metal-die interface during high pressure die casting process and solidification of the magnesium alloy AM60. Multiple runs of the commercial casting simulation package, ProCASttM, were used to model the mold filling and solidification events employing a range of interfacial heat transfer coefficient values. the simulation results were used to estimate the centerline cooling curve at various locations through the casting. the centerline cooling curves, together with the die temperature and the thermodynamic properties of the alloy, were then used as inputs to compute the solution to the Stefan problem of a moving phase boundary, thereby providing the through-thickness cooling curves at each chosen location of the casting, Finally, the local cooling rate was used to calculate the resulting grain size via previously established relationships. the effects of die temperature, filling time and heat transfer coefficient on the grain structure in skin region and core region were quantitatively characterized. It was observed that the grain size of skin region strongly depends on above three factors whereas the grain size of core region shows dependence on the interracial heat transfer coefficient and thickness of the samples. the grain size distribution from surface to center was estimated from the relationship between grain size and the predicted cooling rate. the prediction of grain size matches well with experimental results. A comparison of the predicted and experimentally determined grain size profiles enables the determination of the apparent interracial heat transfer coefficient for different locations.

关键词： High pressure die casting Grain size lnterfacial heat transfer coefficient Solidification of magnesium alloys Process parameters

Effect of Long-term thermal Exposure on Microstructure and Stress Rupture Properties of GH3535 Superalloy

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journal of Materials Science & technology 2015年第3期31卷 269-279页

作者： t.Liu j.S.Dong L.Wang Z.j.Li X.t.Zhou L.H.Lou j.Zhang School of Materials Science and Engineering Dalian University of Technology Institute of Metal Research Chinese Academy of Sciences Shanghai Institute of Applied Physics Chinese Academy of Sciences Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

the evolution of microstructure and the stress rupture properties of long term thermally exposed GH3535 alloy have been investigated. It was found that M6 C carbides presented in the solid solution heat treated samples. During long term thermal exposure at 700 C, fine M12 C carbides precipitated preferentially at grain boundaries. these carbides coexisted with the pre-exiting M6 C. the stress rupture life of700 C/1000 h exposed sample under creep testing at 650 C/324 MPa is 93 h. It is much longer than that of the solid solution samples. No noticeable changes could be detected in both the microstructure and stress rupture lives when the samples were exposed for time longer than 1000 h M12 C carbides were found to be beneficial to the creep properties. the cracks initiated at the interface of M6 C carbides and matrix, which led to a lower creep rupture life.

关键词： GH3535 superalloy Long term thermal exposure Micro

Unexpected me diastinal mass in a liver transplanted patient

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 199-201页

作者： Giuseppe Losurdo Giuseppe Ingravallo antonio Mongelli Nicola Maurizio Castellaneta antonio Pisani Section of Gastroenterology Department of Emergency and Organ Transplantation University "Aldo Moro" Section of Pathology Department of Emergency and Organ Transplantation University "Aldo Moro"

to the Editor:the risk of de novo cancer increases by 2 to 7-fold after liver transplantation[1].the most common de novo cancers are both solid(non-melanoma skin cancers,colorectal carcinoma,genito-urinary and head-neck cancer)[2,3]as well as hematologic malignancies,in particular the so-called post-transplant lymphoproliferative disorder[4].

关键词： mediastinal mass liver transplanted patient post-transplant

Q Inversion and Comparison of Influential Factors among three Methods: CFS, SR, and AA

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Communications in Computational Physics 2020年第6期28卷 356-371页

作者： Yinting Wu j.t.Wu School of Geological and Surveying&Mapping Engineering Chang’an UniversityXi’an 710064P.R.China School of CML Engineering&Architecture Ningbo Institute of TechnologyZhejiang UniversityNingbo 315100P.R.China

the goals of this study were to examine factors influencing Q inversion and to provide references for practical *** different methods for inverting Q values with VSP data were explored,including centroid frequency shift(CFS),spectral ratio(SR),and amplitude attenuation(AA).Comparison between the CFS and the other two methods was conducted on frequency band widths and low attenuation,wavefield components,interface interference,and thin *** from several sets of VSP modeling data indicated that the CFS method is more stable and accurate for dealing with thin and high Q *** band width,especially the presence of high frequencies,influences the inversion effect of all three *** wider the band,the better the results.Q inversion from downgoing wavefield was very similar to that of the upgoing *** CFS method had fewer outliers or skip values from the full wavefield than the other two ***,the applications to Q inversion for the set of field VSP data demonstrated that the Q curves from the CFS method coincided with the geological interpretations better than the Q curves of the other ***,inverse Q filtering shifted the frequency component from 25 Hz to 35 *** results demonstrated that the Q curve is more sensitive to geological horizons than velocity.

关键词： Q inversion centroid frequency shift amplitude attenuation spectral ratio zero-offset VSP data

Flame spray pyrolysis for the one-step fabrication of transition metal oxide films:Recent progress in electrochemical and photoelectrochemical water splitting

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Chinese Chemical Letters 2020年第3期31卷 601-604页

作者： Hongjun Chen Hemant Kumar Mulmudi antonio tricoli Nanotechnology Research Laboratory Research School of ElectricalEnergy and Materials EngineeringCollege of Engineering and Computer ScienceAustralian National UniversityCanberra 2601Australia

Developing large scale deposition techniques to fabricate thin porous films with suitable opto-electro nic properties for water catalysis is a necessity to mitigate climate change and have a sustainable *** this review,flame spray pyrolysis(FSP)technique,a rapid and scalable methodology to synthesize nanostructured transitional metal oxide films with designed functionalities,is firstly ***,applications in electrochemical(EC)and photoelectrochemical(PEC)water splitting for the production of hydrogen fuel is also *** high combustion temperature and the aggregation of flame aerosol ensure that the FSP-made films possess high crystallinity,tunable porosity and high surface areas,making this method suitable either as catalysts for EC water splitting or as efficient semiconductor materials for PEC water ***,a perspective on the next generation FSP engineered films with potential applications in energy storage and conversion is described.

关键词： Scalable One-step Flame-spray pyrolysis transition metal oxide Electrochemical Photoelectrochemical Water splitting

A Modified Multiple Matching Method Based on Equipoise Pseudomulti-Channel Filter and Huber Nor

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Communications in Computational Physics 2020年第6期28卷 498-517页

this study is aimed at improving multiple adaptive *** propose a modified pseudomulti-channel matching method based on the Huber norm,to adjust the matching differences on frequency and phase between the predicted multi-ples and original *** second-order derivative of the predicted multiples is utilized to replace the derivative of its Hilbert *** to the additional frequency term,this method can enhance the high-frequency *** introduce 180◦phase rotation of the multiple channels,which can decrease phase *** Huber norm interpolates between smooth L2 norm treatment of small residuals and robust L1 norm treatment of large *** method can eliminate the restriction of large value conditions from the L2 norm and weaken the condition of orthogonality from the L1 *** applications of the Pluto and Delft models shows that compared with pseudomulti-channel matching filter,the main frequency is increased from 36 Hz to 38 Hz,and the primary reflection wave is more *** practical application of field data verifies the effectiveness of the proposed method.

关键词： Multiple adaptive matching filter equipoise pseudomulti-channel Huber norm second-order derivative