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Flue gas analysis for biomass and coal co‑fring in fuidized bed:process simulation and validation

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International Journal of Coal Science & Technology 2022年第4期9卷 71-81页

作者： Daulet Zhakupov Lyazzat Kulmukanova Yerbol Sarbassov Dhawal shah Department of Chemical and Materials Engineering School of Engineering and Digital SciencesNazarbayev University010001 Nur-SultanKazakhstan

Coal-conversion technologies,although used ubiquitously,are often discredited due to high pollutant emissions,thereby emphasizing a dire need to optimize the combustion *** co-fring of coal/biomass in a fuidized bed reactor has been an efcient way to optimize the pollutants ***,a new model has been designed in Aspen Plus®to simultaneously include detailed reaction kinetics,volatile compositions,tar combustion,and hydrodynamics of the *** of the process model was done with variations in the fuel including high-sulfur Spanish lignite,high-ash Ekibastuz coal,wood pellets,and locally collected municipal solid waste(MSW)and the temperature ranging from 1073 to 1223 *** composition of the exhaust gases,namely,CO/CO_(2)/NO/SO_(2)were determined from the model to be within 2%of the experimental ***-combustion of local MSW with Ekibastuz coal had fue gas composition ranging from 1000 to 5000 ppm of CO,16.2%–17.2%of CO_(2),200–550 ppm of NO,and 130–210 ppm of SO_(2).A sensitivity analysis on co-fring of local biomass and Ekibastuz coal demonstrated the optimal operating temperature for fuidized bed reactor at 1148 K with the recommended biomass-to-coal ratio is 1/4,leading to minimum emissions of CO,NO,and SO_(2).

关键词： Biomass cofring Fluidized-bed combustion Advanced process simulation Flue-gas emissions Fuel utilization Aspen plus

PREPARATION AND CHARACTERIZATION OF SCHIFF BASE POLYMERS DERIVED FROM 4,4'-METHYLENEBIS(CINNAMALDEHYDE)

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Chinese Journal of Polymer Science 2007年第4期25卷 399-407页

作者： M.Y. Khuhawar A. shah M.A. Mughal Dr. M.A. Kazi Institute of Chemistry University of SindhJamshoroSindhPakistan

New Schiff base polymers poly[4,4＇-methylenebis（cinnamaldehyde）ethylenediimine] （PMBCen）, poly[4,4＇- methylenebis（cinnamaldehyde）1,2-propylenediimine] （PMBCPn）, poly[4,4＇-methylenebis（cinnamaldehyde）1,3-propylenediimine] （PMBCPR）, poly[4,4＇-methylenebis（cinnamaldehyde） 1,2-phenylenediimine] （PMBCPh）, poly[4,4＇-methylenebis（cinnamaldehyde）meso-stilbenediimine] （PMBCS）, poly[4,4＇-methylenebis（cinnamaldehyde）urea] （PMBCUR）, poly[4,4＇- methylenebis（cinnamaldehyde）semicarbazone] （PMBCSc）, poly[4,4＇-methylenebis（cinnamaldehyde）thiosemicarbazone] （PMBCTSc） and poly[4,4＇-methylenebis（cinnamaldehyde）hydrazone] （PMBCH） were formed by polycondensation of 4,4＇- methylenebis（cinnamaldehyde） with ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,2-phenylenediamine, meso-stilbenediamine, urea, semicarbazide, thiosemicarbazide and hydrazine, respectively. The dialdehyde and polymers have been characterized through elemental micro-analysis, IR, UV-Vis and ^1H-NMR spectroscopic techniques. Thermoanalytical studies and viscous flow of dilute solutions of dialdehyde and its polymers have been examined and compared.

关键词： Schiff base polymers Synthesis Characterization Infrared spectroscopy Ultraviolet-visible spectroscopy Nuclear magnetic resonance Thermogravimetric analysis Differential thermal analysis.

A Study of Gaugeon Formalism for QED in Lorentz Violating Background

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Communications in Theoretical Physics 2018年第2期69卷 166-172页

作者： Mushtaq B.shah Prince A.Ganai Department of Physics National Institute of Technology

At the energy regimes close to Planck scales, the usual structure of Lorentz symmetry fails to address certain fundamental issues and eventually breaks down, thus paving the way for an alternative road map. It is thus argued that some subgroup of proper Lorentz group could stand consistent and might possibly help us to circumvent this *** is this subgroup that goes by the name of Very Special Relativity(VSR). Apart from violating rotational symmetry,VSR is believed to preserve the very tenets of special relativity. The gaugeon formalism due to type-I Yokoyama and type-II Izawa are found to be invariant under BRST symmetry. In this paper, we analyze the scope of this invariance in the scheme of VSR. Furthermore, we will obtain VSR modified Lagrangian density using path integral derivation. We will explore the consistency of VSR with regard to these theories.

关键词： quantum electrodynamics very special relativity BRST symmetry gaugeon formalism

A chromatin modulator sustains self-renewal and enables differentiation of postnatal neural stem and progenitor cells

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Journal of Molecular Cell Biology 2020年第1期12卷 4-16页

作者： Kushani shah Gwendalyn D.King Hao Jiang Department of Biochemistry and Molecular Genetics University of Alabama at BirminghamBirminghamAL 35294USA Department of Neurobiology University of Alabama at BirminghamBirminghamAL 3529AUSA Department of Biochemistry and Molecular Genetics University of VirginiaCharlottesvilleVA 22908USA

It remains unknown whether H3K4 methylation,an epigenetic modification associated with gene activation,regulates fate determination of the postnatal neural stem and progenitor cells(NSPCs).By inactivating the Dpy30 subunit of the major H3K4 methyltransferase complexes in specific regions of mouse brain,we demonstrate a crucial role of efficient H3K4 methylation in maintaining both the self-renewal and differentiation capacity of postnatal ***30 deficiency disrupts development of hippocampus and especially the dentate gyrus and subventricular zone,the major regions for postnatal NSC ***30 is indispensable for sustaining the self-renewal and proliferation of NSPCs in a cell-intrinsic manner and also enables the differentiation of mouse and human neural progenitor cells to neuronal and glial ***30 directly regulates H3K4 methylation and the induction of several genes critical in *** findings link a prominent epigenetic mechanism of gene expression to the fundamental properties of NSPCs and may have implications in neurodevelopmental disorders.

关键词： neural stem cell self-renewal differentiation epigenetics H3K4 methylation Dpy30

Dependence of effective screening length in granular columns on bead and silo sizes and their ratio

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Chinese Physics B 2013年第5期22卷 591-594页

作者： Abdul Qadir Madad Ali shah Saeed Ahmed Khan Department of Electrical Engineering Sukkur Institute of Business Administration

Apparent mass measurements at the bottom of silos have been carried out. An important parameter in the Janssen model known as the effective screening length has been investigated for different bead and silo diameters as well as of their ratios. It is found that the effective screening length augments with the grain diameter d in addition to the granular column size. It is also revealed that λ exhibits stronger correlation with the bead diameter than that of the silo. This phenomenon is attributed to the reduced-shielding of the vertical stresses to the horizontal ones.

关键词： granular systems granular solids static sand piles granular compaction

Structural,Dielectric and Complex Impedance Spectroscopy Studies of Lead Free Ca_(0.5+x)Nd_(0.5-x)(Ti_(0.5)Fe_(0.5))O_3

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Journal of Materials Science & Technology 2013年第4期29卷 323-329页

作者： M.R.shah A.K.M.Akther Hossain Department of Physics University of PrimeasiaBananiDhaka 1213Bangladesh Department of Physics Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （Rgb） is observed. The Rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.

关键词： Crystal structure Dielectric properties Lead free Perovskite Solid state reaction

Nitriding of Aluminium Alloy in Nitrogen and Nitrogen-Helium Mixture Using 100 Hz-Pulsed DC Glow Discharge

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Plasma Science and Technology 2010年第4期12卷 452-460页

作者： Nasrullah KHAN M.SHOAIB shah R.AHMAD Department of Physics GC University

Nitriding of aluminium alloy （***0.8） in nitrogen and nitrogen-helium mixture was carried out by using 100 Hz-pulsed DC glow discharge. Samples are treated for different durations, namely 4 h, 8 h and 12 h, in nitrogen plasma as well as in a mixture of nitrogen- helium plasma for the same processing duration of 4 h. All nitriding treatments are carried out at an input power of 100 W, filling pressure of 1 mbar and substrates temperature of 250~C. X-ray diffraction （XRD） results show an expansion in lattice spacing and consequently shift of diffraction peaks towards lower angle with the addition of helium in nitrogen plasma. Surface morphology of the treated sample is investigated by scanning electron microscopy （SEM） and energy dispersive X-ray analysis （EDX）. Vickers micro-hardness testing results show increases in surface hardness with processing duration as well as with the addition of helium in nitrogen plasmas. This increase of surface hardness may be attributed to the diffusion of nitrogen content in the surface layer generating internal stresses. It is observed that the addition of helium positively affects the nitriding of samples.

关键词： nitrogen-helium mixture plasma nitriding X-ray diffraction surface hardness

Energy transport for ion acoustic waves in a spin polarized quantum plasma

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Communications in Theoretical Physics 2020年第1期72卷 124-129页

作者： M Ayub Z Iqbal H A shah G Murtaza Salam Chair Department of PhysicsG.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics G.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics Mirpur University of Science and TechnologyMirpur-10250(AJK)Pakistan

The separate spin evolution quantum hydrodynamics(SSE-QHD)model is used to investigate the energy behavior for ion acoustic waves in degenerate quantum *** results show that the energy flow speed decreases with spin polarization *** is also shown that it decreases with the increasing rate up to a certain range of wave number and then it goes to zero *** is observed that Bohm potential suppresses the energy flow *** is also noticed that the energy flow speed deviates from the group velocity even in the absence of Bohm potential ***,the contribution of of Bohm poential effect in spin polarized plasma reduces the extent of deviation.

关键词： spin polarization quantum plasma ion acoustic wave energy flow speed

Approaches to improve quality of care in inflammatory bowel diseases

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World Journal of Gastroenterology 2014年第28期20卷 9281-9285页

作者： Rajesh shah Jason K Hou Department of Medicine Baylor College of Medicine Houston VA HSR&D Center of Excellence Michael E DeBakey Veterans Affairs Medical Center

Studies across medical disciplines have shown gaps in the care recommended in evidence based guidelines and the care actually delivered. Quality improvement projects using systematic audit and feedback interventions such as quality measures, will become increasingly important tools to address these gaps in care. These gaps are also apparent in the care of patients with inflammatory bowel disease. Multiple organizations, including the American Gastroenterology Association and the Crohn’s and Colitis Foundation of America, have developed programs designed to implement quality measures to improve the care of inflammatory bowel disease (IBD) patients. Early results show promise of improving quality, but numerous barriers remain. Gastroenterologists need to be aware of these processes to provide the highest care possible to patients with IBD. We review the existing literature on approaches to quality improvement and their potential application and barriers when applied to IBD care.

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Quality