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Particuology 2015年第5期13卷 72-81页

作者： k.Mahalik Y.k.Mohanty k.c.biswal G.k.Roy J.N.Sahu Department of chemical Engineering Gandhi Institute of Engineering and Technology Department of chemical Engineering National Institute of Technology Department of chemical Engineering Faculty of EngineeringUniversity of Malaya Petroleum and chemical Engineering Programme Area Faculty of EngineeringInstitut Teknologi Brunei(A Technology University)

The present paper describes the statistical modeling and optimization of a multistage gas-solid fluidized bed reactor for the control of hazardous pollutants in flue gas. In this work, we study the hydrodynamics of the pressure drop and minimum fluidization velocity. The hydrodynamics of a three-stage fluidized bed are then compared with those for a single-stage unit. It is observed that the total pressure drop over all stages of the three-stage fluidized bed is less than that of an identical single-stage system. However, the minimum fluidization velocity is higher in the single-stage unit. Under identical conditions, the minimum fluidization velocity is highest in the top bed, and lowest in the bottom bed. This signifies that the behavior of solids changes from a well-mixed flow to a plug-flow, with intermediate behavior in the middle bed.

关键词： Fluidized bed Multi-stage Pressure drop Minimum fluidization velocity Optimization

Photoluminescence upgradation of La_(2)MgTiO_(6):2%Dy^(3+) perovskite with monovalent(Li^(+)),divalent(Ba^(2+),Sr^(2+)) and trivalent(Bi^(3+),Sm^(3+))cation sensitization

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Journal of Rare Earths 2025年第1期43卷 47-56,I0002页

作者： V.P.Veena k.Arun c.k.Shilpa S.V.Jasira k.M.Nissamudeen School of Pure and Applied Physics Kannur UniversityPayyanur CampusEdatKannurKrala67 India Department of Nanoscience and Nanotechnology Kannur UniversityPayyanur CampusEdatkannurKerala670327India

Nano phosphors of 2%Dy^(3+)(wt%)doped La_(2)MgTiO_(6) and monovalent/divalent/trivalent co-doped La_(1.98)Dy_(0.02)MgTiO_(6):x%A^(y+)(A^(y+):Li+,Ba^(2+),Sr^(2+),Bi^(3+),and Sm^(3+);0≤x≤2 wt%)were synthesized by combustion *** the XRD data,it is deduced that an increase in the valency of co-dopant increases the crystallinity of the double perovskite orthorhombic nanocrystal *** an increase in co-dopant size,an elevation in optical bandgap is visible with the highest bandgap of 3.835 eV for Bi^(3+).The photo-absorption is monotonically broadened for Sr^(2+),Sm^(3+),and Li+around 200-450 ***351 nm,Dy^(3+)triggered lattice shows major characteristic emission peaks at 480 nm(^(4)F_(9/2)→^(6)H_(15/2)),574 nm(^(4)F_(9/2)→^(6)H_(13/2)),and 670 nm(^(4)F_(9/2)→^(6)H_(11/2)).leading to near white light emission with cIE coordinates(0.341,0.376).Upon co-doping,the PL intensity is significantly increased with maximum emission for trivalent Sm^(3+),followed by divalent Sr^(2+)and monovalent Li+*** increasing excitation wavelength,Sr^(2+)shows a dominated output and it is found that divalent Sr^(2+)is a potential codopant that could enhance luminescence intensity up to 6 times with a Sr^(2+)→Dy^(3+)energy transfer efficiency of 86%.It is specified that the cIE coordinates of Li+co-doped samples show ideal white emission with color coordinates(0.333,0.336).The concluding outcomes signify the noblest rare earth Sm^(3+)co-doping and thus Sm^(3+)→Dy^(3+)energy transfer mechanism is discussed in detail.

关键词： Photoluminescence Perovskite WLED co-doping Rareearths

characterization and source apportionment of volatile organic compounds in Hong kong:A 5-year study for three different archetypical sites

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Journal of Environmental Sciences 2025年第5期151卷 424-440页

作者： Yuchen Mai Vincent cheung Peter k.k.Louie kenneth Leung Jimmy c.H.Fung Alexis k.H.Lau Donald R.B.lake Dasa Gu Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Environmental Protection Department Hong Kong 999077China Environment and Ecology Bureau Hong Kong 999077China Department of chemistry University of CaliforniaIrvine 92617USA

Initial success has been achieved in Hong kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three *** organic compounds(VOcs)are important for mitigating ozone pollution as its major *** study analyzed VOc characteristics of roadside,suburban,and rural sites in Hong kong to investigate their compositions,concentrations,and source *** showthat the TVOc concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,*** using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,*** findings highlight the importance of identifying and characterizing VOc sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.

关键词： Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation

Biomolecular condensates modulate membrane remodeling

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Molecular Plant 2025年第1期18卷 17-18页

作者： Emma k.Meese Lucia c.Strader Department of Biology Duke UniversityDurhamNCUSA

cellular function relies on numerous diverse processes,all happening *** means by which cells manage these processes is through the use of biomolecular *** membrane-less compartments,often created through phase separation,influence cellular mechanisms ranging from reaction kinetics to biomolecule sequestration(Banani et al.,2017).In plants,biomolecular condensates play roles in desiccation tolerance(Belott et al.,2020),transcriptional control(Powers et al.,2019;Bondos et al.,2021),and a myriad of other diverse processes(Emenecker et al.,2021).Recently,condensates have been discovered to have the ability to exert forces through interactions with cellular *** example,capillary interaction between condensates and other cellular components can generate force;however,more study is necessary to elucidate these mechanisms and interactions(kusumaatmaja et al.,2021;Gouveia et al.,2022).A recent work by Wang et al.(2024)has revealed new insights into how biomolecular condensates may exert forces on membranes through bending and ***,they provide in silico methods and a model to investigate the forces at play during membrane wetting.

关键词： forces kinetics bending

Effect of promoters on dynamics of gas-solid fluidized bed——Statistical and ANN approaches

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china Particuology 2007年第6期5卷 401-407页

作者： Y.k. Mohanty k.c. biswal G.k. Roy B.P. Mohanty Department of chemical Engineering GIET Gunupur 765 022 Rayagada Orissa India Department of chemical Engineering NIT Rourkela 769008 Orissa India

In this study, a bubbling fluidized bed column, 99 mm in inside diameter and 960 mm in height, was used to investigate the effect of rod and disc promoters on fluctuation and expansion ratios. Factorial design （statistical approach） and artificial neural network （ANN） models were developed to predict the fluctuation and expansion ratios in this gas-solid fluidized bed with varying gas flow rates, bed heights, particle sizes and densities. The fluctuation and expansion predicted using these statistical and ANN models, for beds with and without promoters, were found to agree well with corresponding experiments. The statistical model was found to be superior to the ANN model due to its ability to take into account both individual and interactive effects. The rod promoters were found to be more effective in reducing bed fluctuation, and in increasing bed expansion at high gas mass velocities.

关键词： Gas-solid fluidized bed Fluctuation ratio Expansion ratio Promoter Factorial design Artificial neural network

Analysis of convective-radiative heat transfer in dovetail longitudinal fins with shape-dependent hybrid nanofluids: a study using the Hermite wavelet method

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Applied Mathematics and Mechanics(English Edition) 2025年第2期46卷 357-372页

作者： c.G.PAVITHRA B.J.GIREESHA S.SUSHMA k.J.GOWTHAM Department of PG Studies and Research in Mathematics Kuvempu University

A distinguished category of operational fluids, known as hybrid nanofluids,occupies a prominent role among various fluid types owing to its superior heat transfer properties. By employing a dovetail fin profile, this work investigates the thermal reaction of a dynamic fin system to a hybrid nanofluid with shape-based properties, flowing uniformly at a velocity U. The analysis focuses on four distinct types of nanoparticles,i.e., Al2O3, Ag, carbon nanotube (cNT), and graphene. Specifically, two of these particles exhibit a spherical shape, one possesses a cylindrical form, and the final type adopts a platelet morphology. The investigation delves into the pairing of these *** examination employs a combined approach to assess the constructional and thermal exchange characteristics of the hybrid nanofluid. The fin design, under the specified circumstances, gives rise to the derivation of a differential equation. The given equation is then transformed into a dimensionless form. Notably, the Hermite wavelet method is introduced for the first time to address the challenge posed by a moving fin submerged in a hybrid nanofluid with shape-dependent features. To validate the credibility of this research, the results obtained in this study are systematically compared with the numerical simulations. The examination discloses that the highest heat flux is achieved when combining nanoparticles with spherical and platelet shapes.

关键词： Hermite wavelet method radiation convection dovetail fin nanoparticle configuration O351.2

Study on kinetics of thermal decomposition of low LOI goethetic hematite iron ore

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International Journal of Mining Science and Technology 2017年第6期27卷 1031-1036页

作者： Beuria P.c. biswal S.k. Mishra B.k. Roy G.G. Mineral Processing Department CSIR–Institute of Minerals and Materials TechnologyBhubaneswar 751013India Indian Institute of Technology Kharagpur 721302India

In the present study, the kinetics of thermal decomposition of hydrated minerals associated in natural hematite iron ores has been investigated in a fixed bed system using isothermal methods of kinetic analysis. Hydrated minerals in these hematite iron ores are kaolinite, gibbsite and goethite, which contribute to the loss on ignition(LOI) during thermal decomposition. Experiments in fixed bed have been carried out at variable bed depth(16, 32, 48 and 64 mm),temperature(400-1200 ℃) and residence time(30,45, 60 and 75 min) for iron ore samples. It is observed that beyond a certain critical bed depth(16 mm), 100% removal of LOI is not found possible even at higher temperature and higher residence time. Most of the solid-state reactions of isothermal kinetic analysis have been used to analyze the reaction mechanism. The raw data are modified to yield fraction reacted "α" versus time and used for developing various forms of "α" functions.f(α) is the inverse of first derivative of g(α) with respect to α. The study demonstrates that decomposition of hydrated mineral in hematite follows the chemical *** estimated activation energy values in all the experimental situations are found to high, of the order of 60 kJ/mol, reinstating that the reactions are indeed controlled by moving phase boundary and random nucleation.

关键词： Loss on ignition Goethite kaolinite Gibbsite Roasting Pellet feed kinetic analysis

Virtual reality based apps are the future of patient:counseling

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World Journal of clinical cases 2025年第6期13卷 58-60页

作者： Ranjan k Behera Arvind k Morya Parul c Gupta Arshi Singh Department of Ophthalmology MMIMSR Mullana AmbalaAmbala 133207HaryānaIndia Department of Ophthalmology All India Institute of Medical SciencesHyderabad 508126TelanganaIndia Department of Ophthalmology Post Graduate Institute of Medical Education and ResearchChandigarh 160012PunjabIndia Department of Ophthalmology Guru Nanak Eye CentreNew Delhi 110001New DelhiIndia

The use of virtual reality to educate preoperative patients has a positive impact on nurses as well as patients undergoing *** can help improve patient satisfaction and improve favorable outcomes by reducing patient anxiety and proving adequate knowledge about the procedure and possible outcomes to the *** also reduces burden on nursing staff and *** and more diverse cohort studies will help us understand the wider application of this tool on the patient *** may be difficult to apply this tool on elderly patients with failing eyesight,multiple physical ***,there may be reduced acceptance of this modality by older nursing staff and practitioners who may prefer the traditional verbal version for *** will benefit from a combined approach of using virtual reality apps with tradition one-on-one counselling to help alleviate patient concerns and improve patient and healthcare professional satisfaction.

关键词： Nurse Patient Virtual reality counselling Healthcare

kinetics of thermal decomposition of hydrated minerals associated with hematite ore in a fluidized bed reactor

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 229-239页

作者： P.c. Beuria S.k. biswal B.k. Mishra G.G. Roy Institute of Minerals and Materials Technology Council of Scientific & Industrial Research Bhubaneswar-751013 India Indian Institute of Technology Kharagpur-721302 India

The kinetics of removal of loss on ignition(LOI) by thermal decomposition of hydrated minerals present in natural iron ores(i.e.,kaolinite,gibbsite,and goethite) was investigated in a laboratory-scale vertical fluidized bed reactor(FBR) using isothermal methods of kinetic *** in the FBR in batch processes were carried out at different temperatures(300 to 1200°c) and residence time(1 to 30 min) for four different iron ore samples with various LOIs(2.34wt% to 9.83wt%).The operating velocity was maintained in the range from 1.2 to 1.4 times the minimum fluidization velocity(Umf).We observed that,below a certain critical temperature,the FBR did not effectively reduce the LOI to a desired level even with increased residence *** results of this study indicate that the LOI level could be reduced by 90% within 1 min of residence time at 1100°*** kinetics for low-LOI samples(cates two different reaction mechanisms in two temperature *** lower temperatures(300 to 700°c),the kinetics is characterized by a lower activation energy(diffusion-controlled physical moisture removal),followed by a higher activation energy(chemically controlled removal of LOI).In the case of high-LOI samples,three different kinetics mechanisms prevail at different temperature *** temperature up to 450°c,diffusion kinetics prevails(removal of physical moisture);at temperature from 450 to 650°c,chemical kinetics dominates during removal of matrix *** temperatures greater than 650°c,nucleation and growth begins to influence the rate of removal of LOI.

关键词： thermal decomposition fluidized beds kinetic analysis hydrated iron ore activation energy

Prediction of the position of coal particles in an air dense medium fluidized bed system

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International Journal of Mining Science and Technology 2015年第3期25卷 421-427页

作者： Prusti Pallishree Sahu Ashok k. biswal Surendra k. council of Scientific & Industrial Research-Institute of Minerals and Materials Technology

An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to coating on its surface and deposition at dead zone area by fine magnetite ***, the effective density of coal particle increases and the position of coal particle changes accordingly. In this work, an attempt was made to predict the position of coal particle in non-bubbling condition dense medium fluidized bed system. coal particles of different shape such as cubical, rectangular prism,spherical and triangular prism with different projected area and density were used. The results show that the position of coal particle in air dense medium fluidized bed follows descending order with respect to the increase of density, projected area of coal particle and different shapes(i.e., triangular prism, cubical,rectangular prism and spherical). Empirical mathematical correlations were developed to predict the position of coal particle.

关键词： coal beneficiation Pseudo-fluid medium Dead zone area Effective density