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Effect of liner and porcelain application on zirconia surface structure and composition

International Journal of Oral Science 2016年第3期8卷 164-171页

作者： tariq F Alghazzawi Gregg M Janowski Department of Prosthetic Dental Sciences College of DentistryTaibah University Department of Materials Science and Engineering School of EngineeringThe University of Alabama at Birmingham

The purpose of this study was to determine if there is an effect of liner and porcelain application （layering and pressing techniques） on the surface of yttria-stabilized tetragonal zirconia polycrystals （Y-TZP）, which were exposed to permutations of liner, layered porcelain, and pressed porcelain. Scanning electron microscope （SEM）/energy dispersive spectroscope （EDS） was used to identify changes in composition and microstructure after removing liner and porcelain with hydrofluoric acid. Simulated aging was also conducted to determine the effect of liner and porcelain on low-temperature degradation. The control group had a typical equiaxed grain structure, referred to as unaffected. When covered with liner or porcelain, some areas changed in structure and composition and were termed affected. The frequency of affected sbructure decreased when liner was covered with either layered porcelain or pressed porcelain. There were statistical differences （P〈0.05） in the composition between affected and unaffected for zirconium （layered porcelain with liner： affected = 60% （0.8%）（m/m）, unaffected = 69% （4%）, layered porcelain without liner： affected = 59% （3%）, unaffected = 65% （3%）） and oxygen （layered porcelain with liner： affected = 35% （2%）, unaffected = 26% （4%）, layered porcelain without liner： affected = 35% （3%）, unaffected = 30% （2%））. However, there were statistical differences （P〈0.05） in the composition for zirconium and oxygen of the aged layered porcelain without liner only. The liner should not be used before porcelain application, especially when using the layering technique for zirconia restorations. Furthermore, pressing should be considered the technique of choice over layering.

关键词： aging coefficient of thermal expansion energy dispersive spectroscopy layering of porcelain pressing of porcelain scanning electron microscope zirconia

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Helicobacter pylori infection and micronutrient deficiencies

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World Journal of Gastroenterology 2003年第10期9卷 2137-2139页

作者： javed Yakoob Wasim Jafri Shahab Abid Section of Gastroenterology Department of MedicineAga Khan University HospitalStadium RoadKarachiPakistan

It is known that deficiencies of micronutrients due to infections increase morbidity and *** phenomenon depicts itself conspicuously in developing countries. Deficiencies of iron,vitamins A,E,C,B12,etc are widely prevalent among populations living in the third world *** pylori(H pylori)infection has a high prevalence throughout the *** of several micronutrients due to H pylori infection may be concomitantly present and vary from subtle sub-clinical states to severe clinical *** essential trace elements/ micronutrients are involved in host defense mechanisms, maintaining epithelial cell integrity,glycoprotein synthesis, transport mechanisms,myocardial contractility,brain development,cholesterol and glucose *** this paper H pylori infection in associaed with various micronutrients deficiencies is briefly reviewed.

关键词： Helicobacter pylori Avitaminosis Helicobacter Infections Humans Micronutrients

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Seismic fragility assessment of load‐bearing soft‐brick unreinforced masonry piers

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Journal of Safety Science and Resilience 2022年第4期3卷 277-287页

作者： Jayaprakash Vemuri tariq Anwar KVL Subramaniam Department Of Civil Engineering École Centrale School of EngineeringMahindra UniversityTelangana 500043India Department of Earth Science and Engineering(ErSE) King Abdullah University of Science and TechnologyThuwal23955-6900Saudi Arabia Department of Civil Engineering Indian Institute of Technology HyderabadTelangana 502285India

Unreinforced masonry(URM)made with soft bricks comprises a large percentage of the building stock in devel-oping ***,the poor performance of URM piers during earthquakes has led to renewed interest in understanding their behavior under lateral *** experimental data is available on the seismic response,analysis,and design of URMs made of soft *** this study,the micro-modeling technique is used to simulate the in-plane behavior of load-bearing,soft-brick URM *** parameters required in the constitutive models are obtained from material tests and used to develop a calibrated numerical model of the URM *** with various aspect ratios subjected to various axial stresses are numerically modeled to obtain monotonic and cyclic responses,and their critical displacement limit states are *** in the failure modes of masonry piers with variations in the aspect ratio and axial stress are ***-bearing piers exhibit three distinct failure modes:bed sliding,diagonal shear cracking,and flexure,depending on the aspect ratio and axial *** seismic fragility of each pier failure type is examined using nonlinear time history *** results show that bed-sliding piers collapse at extremely low PGA *** failing through diagonal shear cracking also fail at low PGA *** piers can resist seismic forces up to a slightly higher PGA level and thus are the last to *** results also indicate that the effect of uncertainty in ground motions is more significant than the effect of variability in the masonry pier capacities.

关键词： Unreinforced masonry Soft brick Micro-modeling Nonlinear time history analyses Synthetic ground motions Seismic fragility

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Accelerated ultraviolet weathering investigation on micro-/nano-SiO_(2)filled silicone rubber composites

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High Voltage 2018年第4期3卷 295-302页

作者： Muhammad tariq Nazir Bao Toan Phung School of Electrical Engineering and Telecommunications University of New South Wales SydneyNSW 2052Australia

This study attempts to elucidate whether the addition of micro and/or nano-silica(SiO_(2))particles can enhance the resistance of pure polydimethylsiloxane against synergistic effects of UV,temperature and high-voltage *** types of composites(U-SR,M-SR,MN-SR and N-SR)are fabricated by adding micro and/or nano-silica particles and then subjected to multi-stress degradation in a test *** show that there is an apparent surface discoloration in the form of yellowish pale tint and a significant resistance to hydrophobicity reduction is offered by N-SR and MN-SR followed by M-SR and *** electron microscopy and surface roughness findings proclaimed that N-SR and MN-SR offer excellent resistance against filler exposure and an increase in surface *** is a minor reduction in absorbance level of Si(CH_(3))_(2) and Si-O-Si functional groups of composites but interestingly,hydrophilic hydroxyl group absorbance level is found higher in the U-SR ***,dielectric response measurements indicate considerable sensitivity to weathering with N-SR and MN-SR giving the lowest dielectric *** indicate that the addition of nano-silica to pure and micro-silica filled SR can enhance its UV weathering resistance considerably by building an effective UV shielding layer.

关键词： composites filled resistance

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Control Algorithm Based on Limit Cycle Oscillator-FLL for UPQC-S with Optimized PI Gains

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 649-661页

作者： Sabha Raj Arya Sayed javed Alam Papia Ray Department of Electrical Engineering Sardar Vallabhai National Institute of TechnologySuart-395007(Gujarat)gIndia Department of Electrical Engineering Veer Surendra Sai University of Technology(Government University)BurlaSambalpurIndia

This paper involves a limit cycle oscillator-frequency lock loop(LCO-FLL)based control algorithm for unified power quality controllers-S type(UPQC-S)for compensation of reactive power,to maintain a unity power factor,regulate constant voltage at the PCC,mitigate sag,swell and to eliminate *** this approach,an extraction of fundamental in-phase and quadrature components for the estimation of reference signals are taken from the LCO-FLL *** control LCO-FLL provides a high grade of protection against sag-swell voltages,unbalance loading and harmonics present in the utility *** addition to that,it has advantageous characteristics of synchronization with the grid frequency at any previously mentioned conditions without use of phase locked loops or trigonometric *** advantages of the LCO-FLL are to give useful information to estimate fundamental components from a highly polluted grid *** values obtained from the JAYA optimization algorithm are used to fine-tune the proportional integral(PI)controller gains,so that it maintains DC link voltage to the desired *** mean square error(MSE)is employed as an objective function for optimizing the error between actual and reference *** control algorithm based on LCO-FLL is developed in MATLAB/Simulink software and it is tested for power conditioning features.

关键词： JAYA MSE LCO-FLL PI Tuning Sag unbalanced VSC

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Thermal analysis and Joule-Thomson expansion of black hole exhibiting metric-affine gravity

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Chinese Physics C 2024年第1期48卷 173-183页

作者： Muhammad Yasir 夏铁成 Faisal javed G.Mustafa Department of Mathematics Shanghai UniversityShanghai 200444China Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang Institute of Photoelectronics and Zhejiang Institute for Advanced Light Source Zhejiang Normal UniversityJinhua 321004China New Uzbekistan University Mustaqillik Ave.54Tashkent 100007Uzbekistan

This study examines a recently hypothesized black hole,which is a perfect solution of metric-affine gravity with a positive cosmological constant,and its thermodynamic features as well as the Joule-Thomson *** develop some thermodynamical quantities,such as volume,Gibbs free energy,and heat capacity,using the entropy and Hawking *** also examine the first law of thermodynamics and thermal fluctuations,which might eliminate certain black hole *** this regard,a phase transition from unstable to stable is conceivable when the first law order corrections are *** addition,we study the efficiency of this system as a heat engine and the effect of metric-affine gravity for the physical parameters q_(e),q_(m),κ_(s),κ_(d),and κ_(sh).Further,we study the Joule-Thomson coefficient and inversion temperature,and observe the isenthalpic curves in the Ti−Pi *** metric-affine gravity,a comparison is made between a van der Waals fluid and a black hole to study their similarities and differences.

关键词： black hole in metric-affine gravity thermodynamics Joule-Thomson expansion

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Biosorption characteristics of unicellular green alga Chlorella sorokiniana immobilized in loofa sponge for removal of Cr(Ⅲ)

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Journal of Environmental Sciences 2008年第2期20卷 231-239页

作者： AKHTAR Nasreen IQBAL Muhammad ZAFAR Saeed Iqbal IQBAL javed Department of Biology Government lslamia College for WomenCooper RoadLahore-54550Pakistan. Environment Biotechnology Group Biotechnology and Food Research CentrePCSIR Laboratories ComplexLahore-54600Pakistan. School of Biological Sciences University of PunjabLahore-54570Pakistan.

Loofa sponge （LS） immobilized biomass of Chlorella sorokiniana （LSIBCS）, isolated from industrial wastewater, was investigated as a new biosorbent for the removal of Cr（Ⅲ） from aqueous solution. A comparison of the biosorption of Cr（Ⅲ） by LSIBCS and free biomass of C. sorokiniana （FBCS） from 10-300 mg Cr（Ⅲ）/L aqueous solutions showed an increase in uptake of 17.79% when the microalgal biomass was immobilized onto loofa sponge. Maximum biosorption capacity for LSIBCS and FBCS was found to be 69.26 and 58.80 mg Cr（Ⅲ）/g biosorbent, respectively, whereas the amount of Cr（Ⅲ） ions adsorbed onto naked LS was 4.97 mg/g. The kinetics of Cr（Ⅲ） biosorption was extremely rapid and equilibrium was established in about 15 and 20 min by LSIBCS and FBCS, respectively. The biosorption equilibrium was well defined by Langmuir adsorption isotherm model. The biosorption kinetics followed the pseudo-second order kinetic model. The biosorption was found to be pH dependent and the maximum sorption occurred at the solution pH 4.0. Desorption studies showed that 98% of the adsorbed Cr（Ⅲ） could be desorbed with 0.1 mol/L HNO3, while other desorbing agents were less effective in the order： EDTA 〉 H2SO4 〉 CH3COOH 〉 HCl. The regenerated LSIBCS retained 92.68% of the initial Cr（Ⅲ） binding capacity up to five cycles of reuse in continuous flow-fixed bed columns. The study revealed that LSIBCS could be used as an effective biosorbent for the removal of Cr（Ⅲ） from wastewater.

关键词： biosorption immobilization loofa sponge Chlorella sorokiniana Cr(Ⅲ) desorption fixed bed column reactor

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Management of Hepatorenal Syndrome:A Review

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Journal of Clinical and Translational Hepatology 2020年第2期8卷 192-199页

作者： Raseen tariq Ashwani K.Singal Department of Medicine Rochester General HospitalRochesterNYUSA Division of Gastroenterology and Hepatology University of South DakotaSanford School of MedicineSioux FallsSDUSA

Acute kidney injury (AKI) occurs frequently in patients with cirrhosis, and hepatorenal syndrome (HRS) is second most common etiology of AKI after volume responsible pre-renal etiology. AKI in these patients negatively impacts pre- and post-transplant patient survival and healthcare burden. Re-duced effective blood volume with consequent reduced renal blood flow, along with systemic inflammation in patients with decompensated cirrhosis, result in susceptibility to HRS. In this article, we will review updates over the last 5 years on the changing definition with diagnostic criteria and nomenclature of AKI and HRS, data on medical treatment with vasocon-strictors, and urinary biomarkers in diagnosis of etiology of AKI. We will also discuss the significance of liver trans-plantation evaluation once the diagnosis of HRS is established and the post-transplant immunosuppression management. We will also review one of the challenging issues that remains among transplant-eligible patients, that of allocation of si-multaneous liver kidney transplant. Finally, we will review the new implemented policy from the Organ Procurement Trans-plant Network on simultaneous liver kidney allocation.

关键词： HRS Management Liver transplant for HRS

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Pandemic Analysis and Prediction of COVID-19 Using Gaussian Doubling Times

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Computers, Materials & Continua 2022年第7期72卷 833-849页

作者： Saleh Albahli Farman Hassan Ali javed Aun Irtaza Department of Information Technology College of ComputerQassim UniversityBuraydahSaudi Arabia Department of Computer Science University of Engineering and TechnologyTaxilaPakistan Department of Computer Science and Engineering Oakland UniversityMIUSA Department of Computer and Electrical Engineering University of MichiganDearbornUSA

COVID-19 has become a pandemic,with cases all over the world,with widespread disruption in some countries,such as Italy,US,India,South Korea,and *** and reliable detection of COVID-19 is mandatory to control the spread of ***,prediction of COVID-19 spread in near future is also crucial to better plan for the disease *** this purpose,we proposed a robust framework for the analysis,prediction,and detection of *** make reliable estimates on key pandemic parameters and make predictions on the point of inflection and possible washout time for various countries around the *** estimates,analysis and predictions are based on the data gathered fromJohns Hopkins Center during the time span of April 21 to June 27,*** use the normal distribution for simple and quick predictions of the coronavirus pandemic model and estimate the parameters of Gaussian curves using the least square parameter curve fitting for several countries in different *** predictions rely on the possible outcomes of Gaussian time evolution with the central limit theorem of statistics the predictions to be well *** parameters of Gaussian distribution,i.e.,maximumtime and width,are determined through a statisticalχ^(2)-fit for the purpose of doubling times after April 21,*** COVID-19 detection,we proposed a novel method based on the Histogram of Oriented Gradients(HOG)and CNN in multi-class classification scenario i.e.,Normal,COVID-19,viral pneumonia *** results show the effectiveness of our framework for reliable prediction and detection of COVID-19.

关键词： Prediction coronavirus time-series prediction gaussian mathematical model pandemic spreading

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Evaluating location specific strain rates, temperatures,and accumulated strains in friction welds through microstructure modeling

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Defence Technology（防务技术） 2018年第2期14卷 83-92页

作者： javed Akram Prasad Rao Kalvala Vikas Jindal Mano Misra Dept. of Metallurgical Engineering University of Utah Dept. of Metallurgical Engineering Indian Institute of Technology(BHU)

A microstructural simulation method is adopted to predict the location specific strain rates, temperatures, grain evolution, and accumulated strains in the Inconel 718 friction welds. Cellular automata based 2D microstructure model was developed for Inconel 718 alloy using theoretical aspects of dynamic recrystallization. Flow curves were simulated and compared with experimental results using hot deformation parameter obtained from literature work. Using validated model, simulations were performed for friction welds of Inconel 718 alloy generated at three rotational speed i.e., 1200, 1500, and1500 RPM. Results showed the increase in strain rates with increasing rotational speed. These simulated strain rates were found to match with the analytical results. Temperature difference of 150 K was noticed from center to edge of the weld. At all the rotational speeds, the temperature was identical implying steady state temperature(0.89 T_m) attainment.

关键词： Microstructure modeling Dynamic recrystallization Friction welding Inconel 718 EBSD Hot deformation Strain map

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