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The assessment of time dependent flow of Williamson fluid with radiative blood flow against a wedge
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作者 K.Subbarayudu S.Suneetha P.Bala Anki Reddy 《Propulsion and Power Research》 SCIE 2020年第1期87-99,共13页
The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a we... The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a wedge with radiation.The governing equations are transformed into ordinary differential equations by using similarity variables.The analytical solutions of the transformed governing equations are obtained by using the RK 4th order method along with shooting technique solver.The effects of various physical parameters such as Hartmann number,local Weissenberg number,radiation parameter,unsteadiness parameter,Prandtl number,Lewis number,Brownian diffusion,thermophoresis,wedge angle parameter,moving wedge parameter,on velocity,temperature,concentration,skin friction,heat transfer rate and mass transfer rate have been discussed in detail.The velocity and temperature profile deprives for larger We and an opposite trend is observed for concentration.The radiation parameter is propositional to temperature and a counter behaviour is observed for Pr. 展开更多
关键词 The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic WILLIAMSON fluid model. Assuming the flow IS unsteady and blood IS treated as WILLIAMSON fluid over a WEDGE with radiation. The governing EQUATIONS are transformed into ordinary differential EQUATIONS by using similarity variables. The analytical solutions of the transformed governing EQUATIONS are obtained by using the RK 4th order method along with shooting technique solver. The effects of various physical parameters such as Hartmann NUMBER local Weissenberg NUMBER radiation PARAMETER unsteadiness PARAMETER Prandtl NUMBER Lewis NUMBER Brownian diffusion thermophoresis WEDGE angle PARAMETER moving WEDGE PARAMETER on velocity temperature concentration skin friction heat transfer rate and mass transfer rate have been discussed in detail. The velocity and temperature profile deprives for larger We and an opposite trend IS observed for concentration. The radiation PARAMETER IS propositional to temperature and a counter behaviour IS observed for Pr.
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Developments of numerical methods for linear and nonlinear fluid-solid interaction dynamics with applications 被引量:8
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作者 Jing Tang XING 《力学进展》 EI CSCD 北大核心 2016年第1期95-139,共45页
关键词 linear and nonlinear fluid-solid interactions MIXED FE-substructuremethod MIXED FE-BE METHOD MIXED FE-FD METHOD MIXED FE-SP METHOD fluidsloshing acoustic volumestructure coupling breaking WAVE simulations pressurewaves in fluids LNG ship VLFS-water interaction WAVE energy harvesting
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Development of Magnetic Compound Fluid Rubber Sensor for Practical Usage on &gamma;-Irradiation and Energy Harvesting for Broad-Band Electromagnetic Waves 被引量:1
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作者 Kunio Shimada Ryo Ikeda +1 位作者 Hiroshige Kikura Hideharu Takahashi 《World Journal of Mechanics》 2019年第9期205-231,共27页
We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion techniq... We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion technique for rubber and a metal that utilizes a metal complex hydrate, we have developed an MCF rubber sensor. This sensor uses a magnetic compound fluid (MCF), natural rubber (NR-latex) or chloroprene rubber latex (CR-latex), and requires the application of a magnetic field. The potential application of the developed sensor in various engineering scenarios and our daily lives is significant. In this regard, we investigated the effects of &gamma;-irradiation, infrared radiation, microwaves, and a thermal source on the MCF rubber sensor. We established that the MCF rubber is effective enough to be used for power generation of broadband electro-magnetic waves from &gamma;-rays to microwaves, including the range of the solar spectrum, which is the typical characteristic obtained in the present investigation. The remarkable attribute is that the MCF rubber sensor dose is not degraded by &gamma;-irradiation. We also demonstrated the effectiveness of the MCF rubber sensor in energy harvesting. 展开更多
关键词 Γ-IRRADIATION Photovoltaics Energy Harvesting Mechanical Property Thermal Source Infrared Rays Electromagnetic Waves Induced Voltage Natural RUBBER CHLOROPRENE RUBBER Adhesion Electrolytic Polymerization MAGNETIC Cluster MAGNETIC Field MAGNETIC COMPOUND fluid (MCF) Sensing Robot
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Fluid State of Dirac Quantum Particles 被引量:2
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作者 Vu B. Ho 《Journal of Modern Physics》 2018年第14期2402-2419,共18页
In our previous works, we suggest that quantum particles are composite physical objects endowed with the geometric and topological structures of their corresponding differentiable manifolds that would allow them to im... In our previous works, we suggest that quantum particles are composite physical objects endowed with the geometric and topological structures of their corresponding differentiable manifolds that would allow them to imitate and adapt to physical environments. In this work, we show that Dirac equation in fact describes quantum particles as composite structures that are in a fluid state in which the components of the wavefunction can be identified with the stream function and the velocity potential of a potential flow formulated in the theory of classical fluids. We also show that Dirac quantum particles can manifest as standing waves which are the result of the superposition of two fluid flows moving in opposite directions. However, for a steady motion a Dirac quantum particle does not exhibit a wave motion even though it has the potential to establish a wave within its physical structure, therefore, without an external disturbance a Dirac quantum particle may be considered as a classical particle defined in classical physics. And furthermore, from the fact that there are two identical fluid flows in opposite directions within their physical structures, the fluid state model of Dirac quantum particles can be used to explain why fermions are spin-half particles. 展开更多
关键词 DIRAC Equation Wave MECHANICS Stan fluid MECHANICS Stream Function Velocity POTENTIAL POTENTIAL Flow General RELATIVITY Maxwell Field Equations CW Complexes Differential Geometry Topology DIFFERENTIABLE Manifolds Topological Transformation
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Fluid and electrolyte overload in critically ill patients: An overview 被引量:5
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作者 Bruno Adler Maccagnan Pinheiro Besen André Luiz Nunes Gobatto +2 位作者 Lívia Maria Garcia Melro Alexandre Toledo Maciel Marcelo Park 《World Journal of Critical Care Medicine》 2015年第2期116-129,共14页
Fluids are considered the cornerstone of therapy for many shock states, particularly states that are associated with relative or absolute hypovolemia. Fluids are also commonly used for many other purposes, such as ren... Fluids are considered the cornerstone of therapy for many shock states, particularly states that are associated with relative or absolute hypovolemia. Fluids are also commonly used for many other purposes, such as renalprotection from endogenous and exogenous substances, for the safe dilution of medications and as "maintenance" fluids. However, a large amount of evidence from the last decade has shown that fluids can have deleterious effects on several organ functions, both from excessive amounts of fluids and from their non-physiological electrolyte composition. Additionally, fluid prescription is more common in patients with systemic inflammatory response syndrome whose kidneys may have impaired mechanisms of electrolyte and free water excretion. These processes have been studied as separate entities(hypernatremia, hyperchloremic acidosis and progressive fluid accumulation) leading to worse outcomes in many clinical scenarios, including but not limited to acute kidney injury, worsening respiratory function, higher mortality and higher hospital and intensive care unit lengthof-stays. In this review, we synthesize this evidence and describe this phenomenon as fluid and electrolyte overload with potentially deleterious effects. Finally, we propose a strategy to safely use fluids and thereafter wean patients from fluids, along with other caveats to be considered when dealing with fluids in the intensive care unit. 展开更多
关键词 fluid therapy Critically Ill Oliguria Waterelectrolyte balance Central VENOUS pressure RESUSCITATION Acute kidney injury DIURETICS Multiple organ dysfunction SYNDROME Systemic inflammatory response SYNDROME
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地幔岩中不同产状的流体-熔体包裹体及地幔流体交代作用 被引量:3
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作者 谢玉玲 潘琳 +2 位作者 徐九华 邱士东 刘玉堂 《新疆地质》 CAS CSCD 2005年第1期10-13,i001,共5页
地幔捕虏体中存在不同产状的熔体包裹体和各种硅酸盐玻璃相,包括主矿物内部的蠕虫状、长圆形、圆形、不规则状包裹体(I型)、边部的连通的管状包裹体(T型)、主矿物边部和粒间的片状熔融体——“浆胞”(C型),三者可见明显过渡关系,它们是... 地幔捕虏体中存在不同产状的熔体包裹体和各种硅酸盐玻璃相,包括主矿物内部的蠕虫状、长圆形、圆形、不规则状包裹体(I型)、边部的连通的管状包裹体(T型)、主矿物边部和粒间的片状熔融体——“浆胞”(C型),三者可见明显过渡关系,它们是地幔流体交代地幔岩石过程中由交代重熔形成的,是研究地幔流体的特征和地幔交代作用的对象之一.从I型、T型到C型,其成分呈规律变化,其中S、Cu、Ni,K、Na含量呈明显的降低趋势.包裹体中玻璃相的成分较主矿物富Si、Al、S、Cu、Ni、K和Na,再加上CO2包裹体的发现,表明地幔流体的成分富碱金属、Si、Al、S、Cu、Ni和CO2.地幔交代作用可以使交代产物中Si、Al含量升高而形成中酸性岩浆,也可由于硫化物熔体聚集而形成矿浆.不同地区的地幔流体性质可能存在差异,这些不同性质的地幔流体可能与不同类型的地幔成矿作用有关. 展开更多
关键词 Cu Ni Si Al C02 CO2 I T C Na
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Rheological property of low-damage,ideal packing,film-forming amphoteric/sulfonation polymer drilling fluids 被引量:2
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作者 张洪霞 鄢捷年 +1 位作者 舒勇 赵胜英 《Journal of Central South University》 SCIE EI CAS 2008年第S1期429-433,共5页
Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pr... Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations. 展开更多
关键词 low-permeability dense gas condense reservoir AMPHION and SULFONATION polymer drilling fluid DAMAGE controlling water-blocking ideal packing theory(IPT) film-forming agent rheological properties
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耐高温起泡剂膦甲基酚醛树脂PMP的合成及性能 被引量:1
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作者 何耀春 黄步耕 侯士法 《油田化学》 CAS CSCD 北大核心 2004年第4期301-303,306,共4页
由苯酚、甲醛、PCl3合成了水溶性固体膦甲基酚醛树脂(PMP),其HLB值为20 7。简介了合成方法,考察了PMP作为起泡剂的配方性能。PMP溶液室温发泡体积Vf随浓度增大(5~20g/L)而略有增大,泡沫半衰期t1/2在浓度12 5g/L时最长,为20 2min,此时Vf... 由苯酚、甲醛、PCl3合成了水溶性固体膦甲基酚醛树脂(PMP),其HLB值为20 7。简介了合成方法,考察了PMP作为起泡剂的配方性能。PMP溶液室温发泡体积Vf随浓度增大(5~20g/L)而略有增大,泡沫半衰期t1/2在浓度12 5g/L时最长,为20 2min,此时Vf=520mL(/100mL溶液)。在该浓度PMP溶液中分别加入CMC、硅酸钠、三乙醇胺、膨润土使Vf值略降,t1/2值在适宜加量范围大幅延长,加量分别为1 0、2 0、12 5、40g/L时有最大值370 0、85 2、180 2、174 2min;这4个复配PMP/添加剂溶液在温度升高时(30~90℃)Vf值增大但t1/2值大幅缩短。12 5g/LPMP溶液在150~200℃滚动16h后室温下Vf值不变,t1/2值随滚动温度升高而降低,200℃时为11 3min;12 5/2 0/10/40g/LPMP/硅酸钠/三乙醇胺/膨润土溶液在200℃滚动16h后,室温下Vf值为470mL,t1/2值高达50h。PMP为耐高温性能良好的起泡剂,可与硅酸钠、三乙醇胺、膨润土复配使用。图2表4参10。 展开更多
关键词 PMP 2.5g PCl3 HLB 40g f 20g CMC
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Pancreatic fluid collections: What is the ideal imaging technique? 被引量:13
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作者 Narendra Dhaka Jayanta Samanta +4 位作者 Suman Kochhar Navin Kalra Sreekanth Appasani Manish Manrai Rakesh Kochhar 《World Journal of Gastroenterology》 SCIE CAS 2015年第48期13403-13410,共8页
Pancreatic fluid collections(PFCs) are seen in up to 50% of cases of acute pancreatitis. The Revised Atlanta classification categorized these collections on the basis of duration of disease and contents, whether liqui... Pancreatic fluid collections(PFCs) are seen in up to 50% of cases of acute pancreatitis. The Revised Atlanta classification categorized these collections on the basis of duration of disease and contents, whether liquid alone or a mixture of fluid and necrotic debris. Management of these different types of collections differs because of the variable quantity of debris; while patients with pseudocysts can be drained by straight-forward stent placement, walledoff necrosis requires multi-disciplinary approach. Differentiating these collections on the basis of clinical severity alone is not reliable, so imaging is primarily performed. Contrast-enhanced computed tomography is the commonly used modality for the diagnosis and assessment of proportion of solid contents in PFCs; however with certain limitations such as use of iodinated contrast material especially in renal failure patients and radiation exposure. Magnetic resonance imaging(MRI) performs better than computed tomography(CT) in characterization of pancreatic/peripancreatic fluid collections especially for quantification of solid debris and fat necrosis(seen as fat density globules), and is an alternative in those situations where CT is contraindicated. Also magnetic resonance cholangiopancreatography is highly sensitive for detecting pancreatic duct disruption and choledocholithiasis. Endoscopic ultrasound is an evolving technique with higher reproducibility for fluid-to-debris component estimation with the added advantage of being a single stage procedure for both diagnosis(solid debris delineation) and management(drainage of collection) in the same sitting. Recently role of diffusion weighted MRI and positron emission tomography/CT with ^(18)F-FDG labeled autologous leukocytes is also emerging for detection of infection noninvasively. Comparative studies between these imaging modalities are still limited. However we look forward to a time when this gap in literature will be fulfilled. 展开更多
关键词 ACUTE pancreatitis Contrast-enhancedcomputed tomography Magnetic resonance imaging Endoscopic ultrasound Positron emission tomographyscan PANCREATIC fluid COLLECTIONS ACUTE necroticcollections ACUTE peripancreatic fluid COLLECTIONS PSEUDOCYSTS Walled-off necrosis
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Age-Related Surface Oxidases Shed into Body Fluids as Targets to Prevent Skin Aging and Reduce Cardiovascular Risk
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作者 D. James Morré Dale Kern +2 位作者 Christiaan Meadows Helen Knaggs Dorothy M. Morré 《World Journal of Cardiovascular Diseases》 2014年第3期119-129,共11页
Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially... Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially membrane anchored, all functionally similar, with the N-termini exposed at the cell’s exterior. ECTO-NOXes are cell surface proteins with both time-keeping CoQH2 [NAD(P)H] oxidase and protein disulfidethiol interchange activities. They are designated as ECTO-NOX proteins because of their localization on the outer surface of the plasma membrane and to distinguish them from the phox-NOXes of host defense. A ca. 30 kDa N-terminal fragment is cleaved and accumulates in body fluids (serum, saliva, urine, perspiration). arNOXes appear around age 30 and increase steadily thereafter. Reduced quinones, i.e., reduced coenzyme Q, of the plasma membrane are natural substrates. NAD(P)H is oxidized as an artificial substrate. In one phase of the arNOX cycle electrons are transferred to oxygen to generate superoxide. Substrates for the shed forms of arNOX appear to be proteins of body fluids. Circulating lipoproteins and skin matrix proteins emerge as potentially important health-related targets. Through oxidation of collagen, elastin and other proteins of the skin matrix, arNOXes are major contributors to skin aging through tyrosine and thiol oxidation and subsequent cross linking. The main destructive action of arNOX, however, may be to directly oxidize circulating lipoproteins. arNOX in the blood is structured as an integral component of the LDL particle through site-specific binding. As such, arNOXes are implicated as major risk factors for cardiovascular disease due to specific oxidation of LDLs. The superoxide produced and its conversion to hydrogen peroxide would be one part of the potentially destructive properties by contribution to lipid oxidation. Inhibition of arNOX proteins provides a rational basis for anti-aging interventions and their elimination as a major risk factor of atherogenesis. 展开更多
关键词 Atherosclerosis Cardiovascular Risk AGE-RELATED NADH OXIDASE (arNOX) TM9 SUPERFAMILY of TRANSMEMBRANE Proteins Serum and Body fluids Saliva Skin Aging Low Density LIPOPROTEINS
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Carbon Black and Multi Wall Carbon Nanotubes Loaded Polyurethane Foam Composite Flexible Thermal Radiator
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作者 R. Wijesiriwardana 《Journal of Materials Science and Chemical Engineering》 2015年第7期119-126,共8页
Carbon black (CB) or multi walled carbon nanotubes (MWCNT) loaded polyurethane conductive foams are used as heaters, electrodes, radar absorbers and shielding. This paper discusses the performance of an innovative fle... Carbon black (CB) or multi walled carbon nanotubes (MWCNT) loaded polyurethane conductive foams are used as heaters, electrodes, radar absorbers and shielding. This paper discusses the performance of an innovative flexible thermal radiator (FTR) constructed with CB filled or MWCNT filled conductive foam and powering electrode structure constructed with textiles manufacturing process (knitting, weaving or nonwoven). Silver (Ag) yarns are used for the powering electrodes construction. This paper discusses the construction, electro-thermal analysis, performance and applications of FTR. Also this paper compare the thermal and electrical characteristics of CB filled and MWCNT filled FTRs. The electro-thermal model is simulated by using finite element methods. 展开更多
关键词 CARBON Black (CB) Multi Walled CARBON Nanotubes (MWCNT) FLEXIBLE THERMAL RADIATOR (FTR) Ag Yarns KNITTING Electro-Thermal FEM Conductive foam Weaving and Nonwoven
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A new constitutive theory for extrusion-extensional flow of anisotropic liquid crystalline polymer fluid
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作者 Shifang Han 《Natural Science》 2011年第4期307-318,共12页
A new continuum theory of the constitutive equation of co-rotational derivative type was developed by the author for anisotropic viscoelastic fluid-liquid crystalline (LC) polymers (S.F. Han, 2008, 2010) . This paper ... A new continuum theory of the constitutive equation of co-rotational derivative type was developed by the author for anisotropic viscoelastic fluid-liquid crystalline (LC) polymers (S.F. Han, 2008, 2010) . This paper is a continuation of the recent publication [1] to study extrusion-extensional flow of the fluid. A new concept of simple anisotropic fluid is introduced. On the basis of anisotropic simple fluid, stress behavior is described by velocity gradient tensor F and spin tensor W instead of the velocity gradient tensor D in the classic Leslie?Ericksen continuum theory. A special form of the constitutive equation of the co-rotational type is established for the fluid. Using the special form of the constitutive equation in components a computational analytical theory of the extrusion-extensional flow is developed for the LC polymer liquids - anisotropic viscoelastic fluid. Application of the constitutive theory to the flow is successful in predicting bifurcation of elongational viscosity and contraction of extrudate for LC polymer liquids–anisotropic viscoelastic fluid. The contraction of extrudate of LC polymer liquids may be associated with the stored elastic energy conversion into that necessary for bifurcation of elongational viscosity in extrusion extensional flow of the fluid. 展开更多
关键词 Constitutive Equation of Co-Rotational Derivative Type Simple ANISOTROPIC fluid Liquid Crystalline POLYMER Extrusion-Extensional Flow Bifurcation of Elongational Viscosity Contraction of EXTRUDATE of LC POLYMER Liquids
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Experimental investigation of the effects of oil asphaltene content on CO_(2) foam stability in the presence of nanoparticles and sodium dodecyl sulfate
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作者 SADEGHI Hossein KHAZ'ALI Ali Reza MOHAMMADI Mohsen 《Petroleum Exploration and Development》 SCIE 2024年第1期239-250,共12页
Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechani... Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope(SEM),UV adsorption spectrophotometric concentration measurement and Zeta potential measurement.When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 751 s to 239 s,and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s.When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 526 s to 171 s,and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s.In addition,due to asphaltene-SDS/silica interaction in the aqueous phase,the absolute value of Zeta potential decreases,and the surface charges of particles reduce,leading to the reduction of repulsive forces between two interfaces of thin liquid film,which in turn,damages the foam stability. 展开更多
关键词 CO_(2)foam foam stability ASPHALTENE silica nanoparticle sodium dodecyl sulfate(SDS) repulsive forces surface charges Zeta potential
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Engineering of Self-Supported Electrocatalysts on a Three-Dimensional Nickel Foam Platform for Efficient Water Electrolysis
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作者 Ceneng Chen Xian Wang +6 位作者 Zijun Huang Jiahui Mo Xiaoyan Zhang Chao Peng Mohamed Khairy Junjie Ge Zhi Long 《Transactions of Tianjin University》 EI CAS 2024年第2期103-116,共14页
Economical water electrolysis requires highly active non-noble electrocatalysts to overcome the sluggish kinetics of the two half-cell reactions,oxygen evolution reaction,and hydrogen evolution reaction.Although inten... Economical water electrolysis requires highly active non-noble electrocatalysts to overcome the sluggish kinetics of the two half-cell reactions,oxygen evolution reaction,and hydrogen evolution reaction.Although intensive efforts have been committed to achieve a hydrogen economy,the expensive noble metal-based catalysts remain under consideration.Therefore,the engineering of self-supported electrocatalysts prepared using a direct growth strategy on three-dimensional(3D)nickel foam(NF)as a conductive substrate has garnered significant interest.This is due to the large active surface area and 3D porous network offered by these electrocatalysts,which can enhance the synergistic eff ect between the catalyst and the substrate,as well as improve electrocatalytic performance.Hydrothermal-assisted growth,microwave heating,electrodeposition,and other physical methods(i.e.,chemical vapor deposition and plasma treatment)have been applied to NF to fabricate competitive electrocatalysts with low overpotential and high stability.In this review,recent advancements in the development of self-supported electrocatalysts on 3D NF are described.Finally,we provide future perspectives of self-supported electrode platforms in electrochemical water splitting. 展开更多
关键词 Nickel foam Water splitting Surface modification Hydrothermal method Microwave-assisted method ELECTRODEPOSITION Chemical vapor deposition Plasma treatment
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Occupational exposures to blood and body fluids (BBF): Assessment of knowledge, attitude and practice among health care workers in general hospitals in Lebanon
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作者 Ibtissam Sabbah Hala Sabbah +2 位作者 Sanaa Sabbah Hussein Akoum Nabil Droubi 《Health》 2013年第1期70-78,共9页
Healthcare workers (HCWs) who are employed in traditional health care workplaces face a serious danger that may threaten their life;it is their exposure to blood and body fluids (BBF). In Lebanon, the introduction of ... Healthcare workers (HCWs) who are employed in traditional health care workplaces face a serious danger that may threaten their life;it is their exposure to blood and body fluids (BBF). In Lebanon, the introduction of a hospital accreditation system has put a particular emphasis on staff safety, and on the evaluation of professional practice (EPP) programs. Methods: A cross-sectional survey was conducted amongst 277 HCWs working in 4 general hospitals in South Lebanon. Objective: 1) describe the prevalence and the risk factors for occupational exposure to BBF among HCWs;2) evaluate knowledge, attitude, and practices of HCW concerning blood-borne pathogens and adherence to universal safety precautions. Results: The mean age of the respondents was 32.14 years (SD = 10.33), 57.4% were females. 43.3% of HCWs expressed that they use gloves all the time for every activeity of care. 67.1% were aware that needles should not be recapped after use;registered nurses and nursing students were more aware than physicians and nursing assistants (nurse) in this subject. 30% of HCWs declared having had at least one occupational exposure to BBF;62.7% of all accidental exposure was reported to the department responsible for managing exposures. Percutaneous injuries were the most frequently reported. Vaccination coverage was 88.4% for hepatitis B, and 48.4% against influenza. The source patient was tested in 43.4% of reported BBF exposures. Accidental exposure to BBF was more frequent in older people (OR = 3.42;p = 0.03) and the more experienced. Subjects working in intensive care unit ward reported more exposure to BBF (OR = 3;p = 0.04). Participants incurring exposure to BBF resorted to different measures after the injury suggesting a lack of a uniform policy for post-exposure prophylaxis. Conclusion: Exposure to BBF represents an important and frequently preventable occupational hazard for HCWs in Lebanon that requires continuous EPP of HCWs, and a comprehensive approach for prevention and management. 展开更多
关键词 OCCUPATIONAL exposure to BLOOD and body fluids Evaluation of the Professional PRACTICE KNOWLEDGE ATTITUDE and Practices (KAP) Controlled Language Healthcare Workers
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Simultaneous Waveform Inverse Modelling for Litho-Fluid Prediction in an Old Marginal, “Agbbo”Field, Onshore Niger Delta, Nigeria
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作者 Charles Chibueze Ugbor Peter Ogobi Odong Chukwuemeka Austine Okonkwo 《Journal of Geoscience and Environment Protection》 2024年第5期40-59,共20页
Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with un... Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field. 展开更多
关键词 Simultaneous Waveform Inversion Lithofacies fluid Type Rock Physics HYDROCARBON Acoustic Impedance Mu-Rho Reservoir
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Thermodynamic Equilibrium of the Saturated Fluid with a Free Surface Area and the Internal Energy as a Function of the Phase-Specific Volumes and Vapor Pressure 被引量:2
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作者 Albrecht Elsner 《Engineering(科研)》 2015年第9期577-596,共20页
This study is concerned with describing the thermodynamic equilibrium of the saturated fluid with and without a free surface area A. Discussion of the role of A as system variable of the interface phase and an estimat... This study is concerned with describing the thermodynamic equilibrium of the saturated fluid with and without a free surface area A. Discussion of the role of A as system variable of the interface phase and an estimate of the ratio of the respective free energies of systems with and without A show that the system variables given by Gibbs suffice to describe the volumetric properties of the fluid. The well-known Gibbsian expressions for the internal energies of the two-phase fluid, namely for the vapor and for the condensate (liquid or solid), only differ with respect to the phase-specific volumes and . The saturation temperature T, vapor presssure p, and chemical potential are intensive parameters, each of which has the same value everywhere within the fluid, and hence are phase-independent quantities. If one succeeds in representing as a function of and , then the internal energies can also be described by expressions that only differ from one another with respect to their dependence on and . Here it is shown that can be uniquely expressed by the volume function . Therefore, the internal energies can be represented explicitly as functions of the vapor pressure and volumes of the saturated vapor and condensate and are absolutely determined. The hitherto existing problem of applied thermodynamics, calculating the internal energy from the measurable quantities T, p, , and , is thus solved. The same method applies to the calculation of the entropy, chemical potential, and heat capacity. 展开更多
关键词 fluid with Free Surface Area Solution of Gibbss INTERNAL Energy EQUATIONS Chemical Potential Expression CALCULATION of ENTROPY and HEAT Capacity
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Serum and cerebrospinal fluid tau protein level as biomarkers for evaluating acute spinal cord injury severity and motor function outcome 被引量:9
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作者 Ying Tang Hong-Liang Liu +6 位作者 Ling-Xia Min Hao-Shi Yuan Lei Guo Peng-Bo Han Yu-Xin Lu Jian-Feng Zhong Dong-Lin Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第5期896-902,共7页
Tau protein, a microtubule-associated protein, has a high specific expression in neurons and axons. Because traumatic spinal cord injury mainly affects neurons and axons, we speculated that tau protein may be a promis... Tau protein, a microtubule-associated protein, has a high specific expression in neurons and axons. Because traumatic spinal cord injury mainly affects neurons and axons, we speculated that tau protein may be a promising biomarker to reflect the degree of spinal cord injury and prognosis of motor function. In this study, 160 female Sprague-Dawley rats were randomly divided into a sham group, and mild, moderate, and severe spinal cord injury groups. A laminectomy was performed at the T8 level to expose the spinal cord in all groups. A contusion lesion was made with the NYU-MASCIS impactor by dropping a 10 g rod from heights of 12.5 mm(mild), 25 mm(moderate) and 50 mm(severe) upon the exposed dorsal surface of the spinal cord. Tau protein levels were measured in serum and cerebrospinal fluid samples at 1, 6, 12, 24 hours, 3, 7, 14 and 28 days after operation. Locomotor function of all rats was assessed using the Basso, Beattie and Bresnahan locomotor rating scale. Tau protein concentration in the three spinal cord injury groups(both in serum and cerebrospinal fluid) rapidly increased and peaked at 12 hours after spinal cord injury. Statistically significant positive linear correlations were found between tau protein level and spinal cord injury severity in the three spinal cord injury groups, and between the tau protein level and Basso, Beattie, and Bresnahan locomotor rating scale scores. The tau protein level at 12 hours in the three spinal cord injury groups was negatively correlated with Basso, Beattie, and Bresnahan locomotor rating scale scores at 28 days(serum: r =-0.94; cerebrospinal fluid: r =-0.95). Our data suggest that tau protein levels in serum and cerebrospinal fluid might be a promising biomarker for predicting the severity and functional outcome of traumatic spinal cord injury. 展开更多
关键词 nerve REGENERATION spinal cord INJURY tau INJURY SEVERITY OUTCOME cerebrospinal fluid SERUM biomarker Basso Beattie and Bresnahan LOCOMOTOR rating scale neural REGENERATION
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Interaction of Water Waves with Small Undulations on a Porous Bed in a Two-layer Ice-covered Fluid
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作者 Srikumar Panda S.C.Martha 《Journal of Marine Science and Application》 2013年第4期381-392,共12页
The scattering problem involving water waves by small undulation on the porous ocean-bed in a two-layer fluid,is investigated within the framework of the two-dimensional linear water wave theory where the upper layer ... The scattering problem involving water waves by small undulation on the porous ocean-bed in a two-layer fluid,is investigated within the framework of the two-dimensional linear water wave theory where the upper layer is covered by a thin uniform sheet of ice modeled as a thin elastic plate.In such a two-layer fluid there exist waves with two different modes,one with a lower wave number propagate along the ice-cover whilst those with a higher wave number propagate along the interface.An incident wave of a particular wave number gets reflected and transmitted over the bottom undulation into waves of both modes.Perturbation analysis in conjunction with the Fourier transform technique is used to derive the first-order corrections of reflection and transmission coefficients for both the modes due to incident waves of two different modes.One special type of bottom topography is considered as an example to evaluate the related coefficients in detail.These coefficients are depicted in graphical forms to demonstrate the transformation of wave energy between the two modes and also to illustrate the effects of the ice sheet and the porosity of the undulating bed. 展开更多
关键词 two-layer fluid WAVE scattering reflection and transmission coefficients linear water WAVE theory Fourier transform perturbation technique SMALL undulation POROUS BED
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Exposure to Hyaluronan and Radon-Containing Water during the Treatment of Periodontal Pockets
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作者 Ani Gibishvili Mamuka Gogiberidze Marina Nikolaishvili 《Journal of Biosciences and Medicines》 2023年第12期203-217,共15页
Hyaluronic acid (HA) preparations have emerged as pivotal components in contemporary dentistry, gaining widespread recognition for their multifaceted roles in various biological functions. Extensive literature undersc... Hyaluronic acid (HA) preparations have emerged as pivotal components in contemporary dentistry, gaining widespread recognition for their multifaceted roles in various biological functions. Extensive literature underscores the significance of HA in maintaining tissue water balance, fostering cell proliferation, promoting rapid cell migration, influencing cell differentiation during organism development, and facilitating tissue regeneration. Notably, HA’s interactions with cell surface receptors contribute to the viscosity of synovial fluid, activate the immune system, and enhance cartilage elasticity. Beyond these established functions, HA has also been investigated for its potential involvement in determining and studying the hormetic effects of radon water, adding a novel dimension to its applications in dental research. A thorough exploration of existing studies reveals a nuanced understanding of how HA interventions impact the outcomes of dental procedures. The comprehensive scope of these investigations allows for a more accurate assessment of the potential effectiveness of specific interventions and provides valuable insights into post-procedural prognoses for individual patients. This synthesis of literature serves as the foundation for elucidating the intricate interplay between HA, radon exposure, and their relevance in modern dental practices. 展开更多
关键词 Hyaluronic Acid Dental Practice Biological Functions Tissue Water Balance Cell Proliferation Cell Migration Cell Differentiation Tissue Regeneration Synovial fluid Viscosity Immune System Activation Cartilage Elasticity Radon Water Hormetic Effects Dental Research Intervention Effectiveness Post-Procedural Prognosis Risk Factors Inflammatory Periodontal Diseases Chronic Somatic Diseases Gastrointestinal Tract Disorders Respiratory Susceptibility Hereditary Predisposition Lifestyle Factors Smoking Dietary Preferences
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