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Journal of Materials Science & Technology 1998年第3期14卷 241-246页

作者： Mahdy, g.a. Mahmoud, S.S. Chemistry Dept. Faculty of Science Helwan University Helwan Cairo Egypt Chemistry Dept. University College for Women Ain-Shams University Helopolis Cairo Egypt

The effect of fluoride ions on the formation and dissolution behaviour of anodic oxide films on Ti has been investigated in acidic fluoride media (pH=1) using impedance and galvanostatic techniques. A5 the fluoride ion concentration and temperature increase the rate of oxide film formation decreases while the dissolution process increases. oxide film formed at high tem-perature and formation voltage was found to contain more defect sites in the film than that formed at a lower one. Activation energies are calculated during the oxide film formation and dissolution and found to be 20.76 and 28.72 kJ/mol, respectively. Formation rate and reciprocal capacitance data are reported as a function of polarizing current density. Values are recorded for the electrolytic parameters A and B. Potentiostatic curves are derived from the galvanostatic results.

关键词： Figure Macroscopic Studies on the Properties of the Anodic Oxide Films on Titanium

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering.a.d the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering.a.d post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Residuated Completely Simple Semigroups

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Algebra Colloquium 2014年第2期21卷 181-194页

作者： T.S. Blyth g.a. Pinto Mathematical Institute University of St Andrews Scotland Instituto Piaget Campus Universitario de Almada Quinta da Arreinela de Cima 2800-305 Almada Portugal Universidade Atlantica Instituto de Investigagao Cientifica e Tecnologica Fabrica da Polvora 2730-036 Barcarena Portugal

We consider particular compatible orders on a given completely simple semi- group Sx= M（（x）; I, A; P） where （x） is an ordered cyclic group with x 〉 1 and p11= x-1. Of these, only the lexicog.a.hic and bootlace orders yield residuated semigroups. With the lexicog.a.hic order, Sx is orthodox and has a biggest idempotent. With the bootlace order, the maximal idempotents of Sx are identified by specific locations in the sandwich matrix. In the orthodox case there is also a biggest idempotent and, for sandwich matrices of a given size, uniqueness up to ordered semigroup isomorphism is established.

关键词： lexicog.a.hic order bootlace order residuated completely simple semigroup

Stepping up after spinal cord injury:negotiating.a. obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning.a.e transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Assessment of deterioration in RHA-concrete due to magnesium sulphate attack

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 691-696页

作者： g.a. Habeeb H.B. Mahmud N.B.A.A. Hamid Department of Civil Engineering Faculty of Engineering University of Malaya

The assessment of magnesium sulphate attack on concretes containing rice husk ash （RHA, 20wt% of the cementitious materials） with various average particle sizes was investigated. The total cementitious materials were 390 kg.a.d the water-to-binder ratio （W/B） was 0.53 for all mixtures. Specimens were initially cured in water for 7 d and then immersed in the 3wt% magnesium sulphate solution for up to 111 d of exposure. The specimens were subjected to drying-wetting cycles to accelerate sulphate attack. In addition to the visual monitoring of the specimens, the concrete specimens were subsequently tested for compressive strength, dynamic modulus of elasticity, and length and mass changes. The results show that the specimens exposed to sulphate attack exhibit higher strength and dynamic modulus than those kept in water. The length change is negligible and can be attributed to the normal swelling of concrete. On the other hand, concretes suffers mass loss and surface spalling.a.d softening; the fine RHA-concrete results in a better resistance. For the accelerated sulphate attack method used in this study, mass change and visual monitoring.a.e recommended for assessing the deterioration degree and the effectiveness of supplementary cementitious materials to resist sulphate attack.

关键词： concretes pozzolan ettringite rice husk ash (RHA) magnesium sulphate

Nutritional assessment in cirrhotic patients with hepatic encephalopathy

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World Journal of Hepatology 2015年第30期7卷 2940-2954页

作者： Fernando gomes romeiro Lais Augusti gastroenterology Division Department of Internal Medicine-Botucatu Medical SchoolUNESP-Univ Estadual PaulistaBotucatu 18608-917Sao PauloBrazil

Hepatic encephalopathy(HE) is one of the worst complications of liver disease and can be greatly influenced by nutritional status. Ammonia metabolism, inflammation and muscle wasting.a.e relevant processes in HE pathophysiology. Malnutrition worsens the prognosis in HE, requiring early assessment of nutritional status of these patients. Body composition changes induced by liver disease and limitations superimposed by HE hamper the proper accomplishment of exams in this population, but evidence is growing that assessment of muscle mass and muscle function is mandatory due to the role of skeletal muscles in ammonia metabolism. In this review, we present the pathophysiological aspects involved in HE to support further discussion about advantages and drawbacks of some methods for evaluating the nutritional status of cirrhotic patients with HE, focusing on body composition.

关键词： Hepatic encephalopathy Liver cirrhosis Malnutrition Anthropometry Muscle strength Electric impedance Nutrition assessment Dual-energy X-ray absorptiometry

Effects of meal size and proximal-distal segmentation on gastric activity

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World Journal of gastroenterology 2010年第46期16卷 5861-5868页

作者： Madileine F Américo Marjorie V Ietsugu Fernando g romeiro Luciana A Corá Ricardo B Oliveira José Ricardo A Miranda Department of Physics and Biophysics IBBUNESP-Sao Paulo State University Institute of Biological Sciences and Health ICBSUFMT-University of Mato Grosso Department of Clinical Medicine FMBUNESP-Sao Paulo State University Department of Clinical Medicine FMRPUSP-University of So Paulo UNCISAL-Alag.a. State University of Health Sciences

AIM:To evaluate the effects of meal size and three segmentations on intragastric distribution of the meal and gastric motility,by ***:Twelve healthy volunteers were randomly assessed,twice,by *** test meal consisted of 60 or 180 mL of yogurt labeled with 64 MBq 99m Tc-tin *** and posterior dynamic frames were simultaneously acquired for 18 min and all data were analyzed in *** proximal-distal segmentations using regions of interest were adopted for both ***:Intragastric distribution of the meal between the proximal and distal compartments was strongly influenced by the way in which the stomach was divided,showing greater proximal retention after the 180 *** important finding was that both dominant frequencies (1 and 3 cpm) were simultaneously recorded in the proximal and distal stomach;however,the power ratio of those dominant frequencies varied in agreement with the segmentation adopted and was independent of the meal ***:It was possible to simultaneously evaluate the static intragastric distribution and phasic contractility from the same recording using our scintig.a.hic approach.

关键词： gastric motility Phasic contractions Proximal stomach Scintig.a.hy Meal size

STUDY OF RAY IRRADIATION ON DIAMOND-LIKE CARBON FILMS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 26-32页

作者： g.a. Liu T.M. Wang E.Q Dept. of Appl. Phy. Southwest Jiaotong Univ. Chengdu 610031 China

Diamond-like carbon (DLC) films have been deposited on g.a.s substrates using.a.io-frequency (rf) plasma deposition method. gamma -ray, ultraviolet (UV) ray were used toirradiate the DLC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe changing characteristics of SP^3 C-H bond and hydrogen content in the films due to theirradiations. The results show that, the damage degrees induced by the UV ray on the SP^3 C-H bondsare much stronger than that by the gamma -ray. When the irradiation dose of gamma -ray reaches 1 OX10^4 gy, the SP^3 C-H bond reduces about 50 percent in number. The square electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using the results on optical gap of the films and the fully constrained network theory,the hydrogen content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film gamma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling.a.d cerebral perfusion.

关键词： cerebral perfusion electronic