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Finding Dirac Spin Effect in NUT Spacetime

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Communications in Theoretical Physics 2010年第5期53卷 864-868页

作者： m.Korunur m.Salti i.Acikgoz Department of Physics Faculty of Art and Science Dicle University

in the present study, we are interested in finding the spin precession of a Dirac particle in expanding and rotating NUT spaeetime. A tetrad with two functions to be determined is applied to the field equation of the teleparallel theory of gravity via a coordinate transformation. The vector, the axial-vector and the tensor parts of the torsion tensor are obtained. We found that the vector parts are in the radial and Ф-directions. The axial-vector torsion is along r-direction while its other components along θ and oh-directions vanish everywhere. The vector connected with Dirac spin has been evaluated as well.

关键词： NUT spacetime axial-vector torsion Dirac particle

Nano-Enhanced Dairy Scum Biodiesel Blends:Unleashing the Power of Aluminium Oxide for Sustainable and Efficient Engine Performance

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Journal of Thermal Science 2025年第1期 283-302页

作者： Veeranna mODi Prasad B.RAmPURE Sunil Kumar SHETTY madeva NAGARAL Channa Keshava NAiK N Johar mGm muhammad irsyad ABDULLAH Abdullah i.AL-mANSOUR Shamshad ALAm KLE College of Engineering and Technology ChikodiVisvesvaraya Technological University Nitte (Deemed to be University) NMAM Institute of Technology (NMAMIT)Department of Mechanical Engineering Aircraft Research and Design Centre HAL Department of mechanical Engineering BGS College of Engineering and TechnologyBengaluruAffiliated to Visvesvaraya Technological University management and Science University Department of Civil Engineering College of EngineeringKing Saud University

This study investigates the effect of aluminium oxide nanoparticlesaddition to biodiesel blends made from dairy milk scum on performance and combustion characteristics of the diesel *** dispersion of Al2O3nanoparticles in B20 blends at different concentrations was done with the help of *** number of blends were prepared for the *** machine learning algorithms(Random Forest（RF）and CatBoost) was used for the *** results show that in comparison to biodiesel blends without nanoparticles,the kinematic viscosity and density is higher for fuel blends with *** these Fuel blends have higher calorific *** blends exhibited reduced Brake Specific Fuel Consumption（BSFC） of2.85% than the blends without nano particles(Dairy Scum methyl Ester Biodiesel 20%+Neat Diesel 80%（in volume）,DSmEB20),57.14% less CO,40.8% less hydrocarbon,and increased NOxemissions compared to conventional diesel,contributing to the development of environmentally friendly and renewable biofuel blends with *** B20NP30 is the optimal blend for performance and emission *** study concludes with findings on enhanced Brake Thermal Efficiency（BTE） of 26.29% in 3×10-5（in volume） Al2O3nanoparticle-blended DSmE B20 and other DSmE B20 fuel blends,emphasizing the importance of optimal nanoparticle *** correlation matrix shows how engine load,efficiency measures（BTE,BSFC）,and emissions（CO,CO2,NOx,Smoke） are connected in complex *** results help us understand the complicated dynamics of engine performance and emission characteristics ***'s diagram for BTE and BSFC shows that CatBoost-based BTE models perform superior to RF-based models during the training as well as testing *** results were obtained for CO and CO2emission results.

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The Diagnostic and Prognostic Value of Serum Procalcitonin among Ventilator Associated Pneumonia Patients

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Open Journal of Respiratory Diseases 2013年第2期3卷 73-78页

作者： Ashraf Abd El Halim Adel Attia taysser Zytoun Hosam Eldeen Salah Chest Department Faculty of Medicine Zagazig University Zagazig Egypt Clinical Pathology Department Faculty of Medicine Zagazig University Zagazig Egypt Critical Care Department Faculty of Medicine Alexandria University Alexandria Egypt

Ventilator-associated pneumonia (VAP) is a complication in as many as 28% of patients who receive mechanical ventilation. Studies have consistently shown that a delay in diagnosis and treatment increases the mortality risk. The aim of this work was to clarify the role of the serum procalcitonin (PCT) in the diagnosis and the prognosis of ventilator associated pneumonia. methods: Forty two VAP patients, 20 non VAP-iCU (on mechanical ventilation) admitted patients and 20 healthy control subjects of similar age and sex were included in the study. PCT levels in serum samples were measured in all subjects. Results: There was a highly statistically significant difference (p value 0.001) between VAP patients on one side and non VAP-iCU patients and healthy control subjects on the other side regarding the mean values of PCT. Also, the mean values of PCT were statistically significantly higher (p 0.001) among died VAP group than the survivor VAP group. There was a statistically positive correlation (p = 0.449), CRiP (R = 0.403) and SOFA (R = 0.437)) and initial PCT serum levels. Conclusions: This study found that the increased PCT serum level is an important diagnostic tool for VAP and the PCT serum levels can predict the outcome of VAP patients. We recommend other larger studies to augment our findings.

关键词： Ventilator-Associated Pneumonia (VAP) Procalcitonin (PCT) Acute Physiology and Chronic Health Evaluation ii (APACHE ii) The Sequential Organ Failure Assessment Score (SOFA) Clinical Pulmonary infection Score (CPiS)

Analytical modeling of self-powered electromechanical piezoelectric bimorph beams with multidirectional excitation

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international Journal of Smart and Nano materials 2011年第3期2卷 134-175页

作者： m.F.Lumentut i.m.Howard Department of mechanical Engineering Curtin UniversityAustralia

Unused mechanical energies can be found in numerous ambient vibration sources in industry including rotating equipment,vehicles,aircraft,piping systems,fluid flow,and even external movement of the human body.A portion of the vibrational energy can be recovered using piezoelectric transduction and stored for subsequent smart system utilization for applications including powering wireless sensor devices for health condition monitoring of rotating machines and defence communication *** vibration environment in the considered application areas is varied and often changes over time and can have components in three perpendicular directions,simultaneously or *** paper presents the development of analytical methods for modeling of self-powered cantilevered piezoelectric bimorph beams with tip mass under simultaneous longitudinal and transverse input base motions utilizing the weak and strong forms of Hamiltonian’s principle and space-and time-dependent eigenfunction series which were further formulated using *** reduced constitutive electromechanical equations of the cantilevered piezoelectric bimorph were subsequently analyzed using Laplace transforms and frequency analysis to give multi-mode frequency response functions(FRFs).The validation between theoretical and experimental results at the single mode of eigenfunction solutions reduced from multi-mode FRFs is also given.

关键词： microelectromechanical system piezoelectric energy harvesting smart sensor Hamiltonian strong weak and closed forms vibration

Effects of forced aeration on community dynamics of free and attached bacteria in copper sulphide ore bioleaching

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international Journal of minerals,metallurgy and materials 2022年第1期29卷 59-69页

作者： Wei Chen Shenghua Yin i.m.S.K.ilankoon Key Laboratory of ministry of Education for High-Efficient mining and Safety of metal University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Discipline of Chemical Engineering School of EngineeringMonash UniversityJalan Lagoon SelatanBandar SunwaySelangor Darul Ehsan 47500Malaysia

Bacterial community dynamics and copper leaching with applied forced aeration were investigated during low-grade copper sulphide bioleaching to obtain better bioleaching *** illustrated that appropriate aeration improved bacterial concentrations and leaching *** highest bacterial concentration and Cu^(2+)concentration after 14-d leaching were 7.61×10^(7) cells·mL^(−1) and 704.9 mg·L^(−1),respectively,at aeration duration of 4 h·d^(−1).The attached bacteria played a significant role during bioleaching from 1 to 7 ***,free bacteria dominated the bioleaching processes from 8 to 14 *** phenomenon was mainly caused by the formation of passivation layer through Fe3+hydrolysis along with bioleaching,which inhibited the contact between the attached bacteria and ***,16S rDNA analysis verified the effect of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans on the bioleaching *** results demonstrate the importance of free and attached bacteria in bioleaching.

关键词： attached bacteria bioleaching forced aeration free bacteria low-grade copper sulphide ore

Functional films based on mechanoactivated starch with prolonged release of preservative

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Food Bioscience 2022年第3期47卷 810-818页

作者： i.m.Lipatova A.A.Yusova L.i.makarova G.A.Krestov institute of Solution Chemistry of the Russian Academy of Sciences 1 Akademicheskaya St.Ivanovo153045Russia

Use of active edible films containing an antimicrobial agent-a new method of extending the shelf life of food *** the controlled release of the preservative from the film is an urgent *** work aims to introduce a new environmentally friendly process for the production of antifungal starch films with a prolonged release of a preservative using mechanoactivation in a rotor-stator device (RSD).Active films based on mechanoactivated starch hydrogels containing 0–5.0% (w/w) benzoic acid as a preservative and chitosan as a solubilizing additive (St-BA-Ch),as well as films containing sodium benzoate (St-SB) for comparison,were obtained by the casting *** were characterized using optical and atomic force microscopy,X-ray diffraction and tensile and moisture permeability testing *** was found that benzoic acid is present in the St-BА-Ch-films in the form of submicron ***-BА-Ch films showed greater tensile strength and a lower release rate of the preservative into model media compared to St-SB *** is established that mechanical activation of casting hydrogels in RSD allows increasing the strength films by an average of 2 times,as well as reducing the release rate of the preservative and the vapor permeability of the *** antifungal activity of the films was confirmed using Aspergillus *** developed active St-BА-Ch film can be recommended for use in the food industry to extend the shelf life of food products.

关键词： Starch films Benzoic acid Sodium benzoate mechanoactivation Rotor–stator device mechanical and barrier properties

Effect of magnesium and nickel coatings on the wetting behavior of alumina toughened zirconia by molten Al-mg alloy

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international Journal of minerals,metallurgy and materials 2012年第1期19卷 77-82页

作者： H. Sharifi A.R. Khavandi m. Divandari m.i. Hasbullah School of materials and metallurgical Engineering iran University of Science and Technology Department of material Engineering Faculty of mechanical Engineering University Teknologi malaysia

The wettability of alumina toughened zirconia （ZTA） by Al-mg alloy was investigated using the sessile drop technique. The ef fects of nickel coating, magnesium content, nitrogen atmosphere, and processing temperature on the contact angle between the molten alloy and the substrate were determined. Likewise, the effect of these factors on the wetting properties was studied. The results showed that the nickel coating on the ceramic substrate caused a significant reduction in solid/liquid surface energy and the contact angle decreased obvi- ously. The presence of magnesium in the molten aluminum alloy in nitrogen atmosphere reduced the contact angle effectively. The presence of magnesium in the alloy must be at a minimum amount of 2wt%-3wt% . moreover, it was suggested that some chemical reactions in the Al-mg-N system led to the production of mg3N2 and AlN compositions. These compositions improved the wetting properties of the systems by reducing the surface energy of the molten. it was shown that increasing the temperature is also an effective factor for the enhancement of wetting properties.

关键词： wetting coatings alumina zirconia ceramic materials composite materials

Stellar Population Analysis of Galaxies based on Genetic Algorithms

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 347-355页

作者： Abdel-Fattah Attia H.A.ismail i.m.Selim A.m.Osman i.A.isaa m.A.marie A.A.Shaker National Research institute of Astronomy and Geophysics(NRiAG) 11421 HelwanCairoEgyptNational Research Institute of Astronomy and Geophysics(NRIAG)11421 HelwanCairoEgypt Cairo University Faculty of ScienceAstronomy DepartmentEgypt

We present a new method for determining the age and relative contribution of different stellar populations in galaxies based on the genetic *** apply this method to the barred spiral galaxy NGC 3384,using CCD images in U,B,V,R and i *** analysis indicates that the galaxy NGC 3384 is mainly inhabited by old stellar population(age〉10^9 yr).Some problems were encountered when numerical simulations are used for determining the contribution of different stellar populations in the integrated color of a *** results show that the proposed genetic algorithm can search efficiently through the very large space of the possible ages.

关键词： methods numerical-galaxies stellar population-galaxies individual(NGC 3384).

Production of porous silica by the combustion of rice husk ash for tundish lining

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Journal of University of Science and Technology Beijing 2008年第3期15卷 307-313页

作者： Y.m.Z.Ahmed E.m.Ewais Z.i.Zaki Central metallurgical Research and Development institute(CmRDi)

in order to study the production of porous silica compacts by the combustion of rice husk ash （RHA） for tundish lining, the experimental design technique was used to evaluate the effect of firing temperature, soaking time and compaction pressure on controlling both the porosity degree and compressive strength of rice husk ash compacts. The results revealed that while the porosity degree of the compacts decreased with the increase in the entire studied parameters, the compressive strength exhibited another trend especially at a lower soaking time. At a lower soaking time, the increase in firing temperature led to a slight decrease in compressive strength and then increasing thereafter. The porous silica compacts having 30% porosity and 〉 2.5 mPa compressive strength suitable for tundish lining could be obtained from the combustion of rice husk ash compacts.

关键词： porous silica rice husk ash tundish lining compressive strength porosity