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气力输送管道压降预测影响的数值模拟研究

武汉理工大学学报 2010年第23期32卷 13-16页

作者：马爱纯 Williams R c 周孑民 Jones M g 中南大学能源科学与工程学院长沙410083 纽卡斯尔大学散装固体及颗粒技术中心纽卡斯尔2308

气力输送管道压降的预测有利于合理设计供风系统。建立了一气力输送实验装置,对某些截面的压力进行了实验测试。运用cfD仿真软件fluent,建立了3维气固两相湍动双流体压降预测模型,通过对该气力输送系统的水平弯管进行的仿真研究,得到了... 详细信息

气力输送管道压降的预测有利于合理设计供风系统。建立了一气力输送实验装置,对某些截面的压力进行了实验测试。运用cfD仿真软件fluent,建立了3维气固两相湍动双流体压降预测模型,通过对该气力输送系统的水平弯管进行的仿真研究,得到了与实验结果吻合较好的模型,并运用该模型分析了几个主要参数对气力输送系统压降预测的影响。

关键词：气力输送压降 cfD 数值模拟

Dissolved organic carbon in permafrost regions: A review

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Science china Earth Sciences 2019年第2期62卷 349-364页

作者： Qiang MA Huijun JIN congrong YU Victor f.BENSE State Key Laboratory of frozen Soils Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences college of Resources and Environment University of chinese Academy of Sciences School of civil Engineering Harbin Institute of Technology State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Hydrology and Quantitative Water Management group Department of Environmental Sciences Wageningen University

A large quantity of organic carbon(c) is stored in northern and elevational permafrost regions. A portion of this large terrestrial organic c pool will be transferred by water into soil solution(～0.4 Pg c yr^(-1))(1 Pg=10^(15) g), rivers (～0.06 Pg c yr^(-1)),wetlands, lakes, and oceans. The lateral transport of dissolved organic carbon(DOc) is the primary pathway, impacting river biogeochemistry and ecosystems. However, climate warming will substantially alter the lateral c shifts in permafrost ***, permafrost, precipitation, soil humidity and temperature, and microbial activities, among many other environmental factors, will shift substantially under a warming climate. It remains uncertain as to what extent the lateral c cycle is responding,and will respond, to climate change. This paper reviews recent studies on terrestrial origins of DOc, biodegradability, transfer pathways, and modelling, and on how to forecast of DOc fluxes in permafrost regions under a warming climate, as well as the potential anthropogenic impacts on DOc in permafrost regions. It is concluded that:(1) surface organic layer, permafrost soils,and vegetation leachates are the main DOc sources, with about 4.72 Pg c DOc stored in the topsoil at depths of 0–1 m in permafrost regions;(2) in-stream DOc concentrations vary spatially and temporally to a relatively small extent (1–60 mg c L^(-1)) and annual export varies from 0.1–10 g c m^(-2) yr^(-1);(3) biodegradability of DOc from the thawing permafrost can be as high as 71%, with a median at 52%;(4) DOc flux is controlled by multiple factors, mainly including vegetation, soil properties,permafrost occurrence, river discharge and other related environmental factors, and(5) many statistical and process-based models have been developed, but model predictions are inconsistent with observational results largely dependent on the individual watershed characteristics and future discharge trends. Thus, it is still difficult to predict how futu

关键词： Dissolved organic carbon (DOc) Aquatic ecosystem carbon biodegradability DOc export Permafrost degradation

Sirtuins and chronic Obstructive Pulmonary Disease

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food and Nutrition Sciences 2018年第10期9卷 1254-1260页

作者： c. carollo c. Urso R. Lo Presti g. caimi Biomedical Department of Internal and Specialistic Medicine University of Palermo Palermo Italy

chronic obstructive pulmonary disease (cOPD) is one of the world leading causes of death. It has been recently related to aging and inflammation, as well as sirtuins are actually recognized to be involved in both these phenomena. Sirtuins are a family of highly conserved protein deacetylases and they influence the factors that worsen physiological aging such as glucose metabolism, DNA stability and cancer, neurodegenerative processes, etc. Among the seven sirtuins, SIRT1 and SIRT6 have been deeply investigated in cOPD. Actually researchers hypothesize that SIRT 1 activators could play a fundamental role in counteract cOPD. Natural compounds as Resveratrol are actually retained SIRT1 activators and could be indicated as powerful weapons against this complex disease.

关键词： Sirtuins chronic Obstructive Pulmonary Disease Resveratrol Wine

Particulate matter geochemistry of a highly industrialized region in the caribbean:Basis for future toxicological studies

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geoscience frontiers 2022年第1期13卷 376-387页

作者： Luis f.O.Silva Ismael L.Schneider Paulo Artaxo Yuleisy Núñez-Blanco Diana Pinto Érico M.M.flores Leandro gómez-Plata Omar Ramírez guilherme L.Dotto Department of civil and Environmental Universidad de la CostaCUCCalle 58#55–66BarranquillaAtlánticoColombia Department of Applied Physics Institute of PhysicsUniversity of São PauloBrazil Department of chemistry Universidade Federal de Santa MariaRSBrazil Universidad Militar Nueva granada(UMNg) Faculty of EngineeringEnvironmental EngineeringKm 2 Cajicá-ZipaquiráColombia chemical Engineering Department Federal University of Santa Maria-UFSM1000Roraima Avenue97105-900 Santa MariaRSBrazil

Air pollution has become an important issue,especially in caribbean urban areas,and,particulate matter(PM)emitted by different natural and anthropogenic sources causes environmental and health *** this work,we studied the concentrations of PM_(10) and PM_(2.5) sources in an industrial and port urban area in the caribbean region of *** samples were collected within 48-h periods between April and October 2018 by using a Partisol 2000 i-D *** geochemical characterization was performed by X-ray fluorescence(XRf)***,ionic species and black carbon(Bc)were quantified by ion chromatography and reflectance spectroscopy,*** the Positive Matrix factorization(PMf)receptor model,the contributions of PM sources were *** average concentration of PM_(10) was 46.6±16.2μg/m^(3),with high concentrations of cl and *** PM_(2.5),the average concentration was 12.0±3.2μg/m^(3),and the most abundant components were Bc,S,and *** receptor model identified five sources for PM_(10) and PM_(2.5).for both fractions,the contributions of marine sea spray,re-suspended soil,and vehicular traffic were *** addition,PM_(2.5) included two mixed sources were found to be fuel oil combustion with fertilizer industry emissions,and secondary aerosol sources with building construction ***,PM_(10) was found to also include building construction emissions with re-suspended soil,and metallurgical industry *** obtained geochemical atmospheric results are important for the implementation of strategies for the continuous improvement of the air quality of the caribbean region.

关键词： Urban air pollution Particulate matter geochemical composition Aerosol source apportionment Receptor models PMf

Percutaneous Implantation of Mitraclip Device： first case Report in the West of Parana

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Journal of Pharmacy and Pharmacology 2018年第5期6卷 515-520页

作者： cassiana Tomazoni, Evandro L. Q. flores Laura g. flores Leandro S. I. Ueda Micheli g. Signor Patricia f.ferreira and Vanessa c. Trentim Sao Lucas Hospital's Department of cardiovascular Sciences University Center of the Assis Gurgacz Foundation Cascavel 85812-130 Brazil

MI （mitral insufficiency） is the most common valvulopathy currently, with surgery being the gold standard treatment. However, about half of patients with severe MI have a high surgical risk because of their age or comorbidities, therefore surgery is contraindicated, In this context, Mitraclip appears, a device that allows the percutaneous treatment of MI and which is presented as a safe alternative and able to improve the quality of life for these patients. This work describes the first procedure performed at a referral hospital in western Parana-Brazil. It is a male patient with mitral valve insufficiency due to mitral prolapse, submitted to endovascular therapy due to the high surgical risk because of his advanced age, presence of comorbidities and left ventricular dysfunction. from this modality, partial regurgitation improvement and intense symptomatic relief were obtained, demonstrating the great potential of the Mitraclip device to improve the quality of life of its patients.

关键词： Mitral valve insufficiency Mitxaclip endovascular.

Microproteinuria in patients with inflammatory bowel disease:Is it associated with the disease activity or the treatment with 5-aminosalicylic acid?

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World Journal of gastroenterology 2006年第5期12卷 739-746页

作者： Androniki c Poulou Konstantinos E goumas Dimitrios c Dandakis Ioannis Tyrmpas Maria Panagiotaki Androniki georgouli Dimitrios c Soutos Athanasios Archimandritis gastroenterology Department of Red cross Hospital of Athens Athanasaki 111521 AthensGreece 2~(nd) Department of Internal Medicine University of Athens Medical School"Hippokratio"General Hospital11521 AthensGreece

AIM： To investigate whether microproteinuria in patients with inflammatory bowel disease （IBD） is associated with the disease activity or the treatment with 5-aminosalicylic acid （5-ASA）. METHODS： We prospectively studied microproteinuria in 86 consecutive patients with IBD, 61 with ulcerative colitis （Uc） and 25 with crohn＇s disease （cD）, before as well as 2 and 6 months after their inclusion in the study. forty-six patients received 5-ASA for a period of 28.8 months （range 1-168 too）. Microalbuminuria （mALB） and urine levels of the renal tubular proteins β2-microglobulin （β2mgLB） and β-N-acetyI-D-glucosamidase （β-NAg） as well as the creatinine clearance were determined in a 12-h overnight urine collection. Tumor necrosis factor-α （TNf-α） serum levels were also measured. RESULTS： A total of 277 measurements （194 in Uc patients and 83 in cD patients） were performed. The prevalence of abnormal microoproteinuria in Uc and cD patients was 12.9% and 6.0% for mALB, 22.7% and 27.7% for B2mgLB, and 11.3% and 8.4% for β-NAg, respectively, mALB was not associated with IBD activity. β2mgLB and B-NAg urine levels were correlated to Uc activity （UcAI： P〈0.01; UcEI： P〈0.005）. mALB in Uc patients and β-NAg urine levels in cD patients were related to TNf-α serum levels. An association was noticed between microproteinuria and smoking habit. Treatment with 5-ASA was not correlated to the severity of microproteinuria or to the changes of creatinine clearance.cONcLUSION： Microproteinuria is mainly associated with Uc and its activity but not affected by 5-ASA.

关键词： Inflammatory bowel disease Microproteinuria 5-aminosalicylic acid

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聚合物色谱分析手册

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Biothermomechanical behavior of skin tissue

作者： c.g.·史密斯(c.g. Smith)等

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Acta Mechanica Sinica 2008年第1期24卷 1-23页

作者： f.Xu T.J.Lu K.A.Seffen Engineering Department Cambridge University Cambridge CB2 1PZ UK MOE Key Laboratory of Strength and Vibration School of Aerospace Xi'an Jiaotong University 710049 Xi'an China

Advances in laser, microwave and similar technologies have led to recent developments of thermal treatments involving skin tissue. The effectiveness of these treatments is governed by the coupled thermal, mechanical, biological and neural responses of the affected tissue： a favorable interaction results in a procedure with relatively little pain and no lasting side effects. currently, even though each behavioral facet is to a certain extent established and understood, none exists to date in the interdisciplinary area. A highly interdisciplinary approach is required for studying the biothermomechanical behavior of skin, involving bioheat transfer, biomechanics and physiology. A comprehensive literature review pertinent to the subject is presented in this paper, covering four subject areas：（a） skin structure, （b） skin bioheat transfer and thermal damage, （c） skin biomechanics, and （d） skin biothermomechanics. The major problems, issues, and topics for further studies are also outlined. This review finds that significant advances in each of these aspects have been achieved in recent years. Although focus is placed upon the biothermomechanical behavior of skin tissue, the fundamental concepts and methodologies reviewed in this paper may also be applicable for studying other soft tissues.

关键词： Review Skin tissue Bioheat transfer Biomechanics Biothermomechanics

The Two-constant cost Model and the Estimation of the cost Performance Evolutions of the Proton Exchange Membrane fuel cell Power generation

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Energy and Power Engineering 2013年第2期5卷 1-10页

作者： H. f. Zhang P. c. Pei State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing China

This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. for this purpose, electricity-cost ratio (EcR) is proposed as the measuring parameter for the cost performance and a two-constant cost model is proposed to concisely describe the cost characteristic of the power generation as the opposite of a multi-constant cost model. combination of the two-constant cost model and the ideal cell model developed recently produces an inclusive EcR equation that has three analytical expressions and thus allows of straight overviews of the cost performance evolutions in the working zones of the cells. The applications to real cells confirm the validity of the equation for operation optimization and technique evaluation of PEM fuel cells. And more insights into the cost performance evolutions are inferred by means of the equation to help promote the commercialization of PEM fuel cells.

关键词： fuel cell cost Performance Lifetime Degradation Energy Efficiency Operation Optimization