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Dynamics of a SIR epidemic model with variable recruitment and quadratic treatment

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生物数学学报:英文版 2023年第7期16卷 219-247页

作者： Manisha mukherjee Biswajit Mondal Department of Mathematics Raja N.L.Khan Women's College Midnapore 721102 West BengalIndia

The dynamical behavior of a variable recruitment SIR model has been investigated with the nonlinear incidence rate and the quadratic treatment function for a horizontally transmitted infectious disease that sustains for a long period(more than one year).For a long duration,we have incorporated human fertility in variable *** societal effort,*** types of medical infrastructures,have a vital role in controlling such a *** this reason,we have considered the quadratic treatment function,which divides the system into two *** have established the existence and stability of different equilibrium points that depend mainly on the societal effort parameter in both subsystems and also global *** rich dynamics such as forward bifurcation,Hopf bifurcation,limit cycle,and Bogdanov-Takens bifurcation of co-dimension 2 have been established by using bifurcation theory and the biological significance of these dynamics has been *** numerical examples have been considered to illustrate the theoretical ***,we have discussed the advantage of our model with the model by Eckalbar and Eckalbar[Nonlinear Anal.:Real World Appl.12(2011)320332].

关键词： Quadratic treatment function endemic equilibrium point Bogdanov-Takens bifurcation disease-free equilibrium point Hopf bifurcation

Beyond Graphene Anode Materials for Emerging Metal Ion Batteries and Supercapacitors

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Nano-Micro Letters 2018年第4期10卷 228-254页

作者： Santanu mukherjee Zhongkan Ren Gurpreet Singh Department of Mechanical and Nuclear Engineering Kansas State University

Intensive research effort is currently focused on the development of efficient, reliable, and environmentally safe electrochemical energy storage systems due to the ever-increasing global energy storage demand. Li ion battery systems have been used as the primary energy storage device over the last three decades. However, low abundance and uneven distribution of lithium and cobalt in the earth crust and the associated cost of these materials, have resulted in a concerted effort to develop beyond lithium electrochemical storage systems. In the case of non-Li ion rechargeable systems, the development of electrode materials is a significant challenge, considering the larger ionic size of the metal-ions and slower kinetics. Two-dimensional(2D) materials, such as graphene, transition metal dichalcogenides, MXenes and phosphorene, have garnered significant attention recently due to their multi-faceted advantageous properties: large surface areas, high electrical and thermal conductivity, mechanical strength, etc. Consequently, the study of 2D materials as negative electrodes is of notable importance as emerging non-Li battery systems continue to generate increasing attention. Among these interesting materials, graphene has already been extensively studied and reviewed, hence this report focuses on 2D materials beyond graphene for emerging non-Li systems. We provide a comparative analysis of 2D material chemistry, structure, and performance parameters as anode materials in rechargeable batteries and supercapacitors.

关键词： Two-dimensional materials Transition metal dichalcogenides MXene Exfoliation Top-down Anodes

Synthesis of hydroxymethylfurfural and furfural from hardwood and softwood pulp using ferric sulphate as catalyst

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 531-542页

作者： Agneev mukherjee Guillermo Portillo-Perez Marie-Josee Dumont Bioresource Engineering Department McGill UniversityQC H9X 3V9Canada

Hydroxymethylfurfural (HMF) and furfural are promising chemicals for the creation of a bio-based economy. The development of an inexpensive catalytic system for converting cellulosic biomass into these chemicals is an important step in this regard. Ferric sulphate is a common, cheap and non-toxic Lewis acid that has been used to catalyse reactions such as wood depolymerisation. In this work, ferric sulphate was used to help the production of HMF and furfural from hardwood and softwood pulps. It was found that for hardwood pulp, the use of ferric sulphate alone gave a maximum HMF yield of 31.6 mol-%. The addition of the ionic liquid [BMIM]Cl or HCl as co-catalysts did not lead to an increase in the yields obtained. A prior decationisation step, however, resulted in HMF yields of 50.4 mol-%. Softwood pulp was harder to depolymerise than hardwood, with a yield of 28.7% obtained using ferric sulphate alone. The maximum HMF yield from softwood, 37.9 mol-%, was obtained using a combination of ferric sulphate and dilute HCl. It was thus concluded that ferric sulphate is a promising catalyst for HMF synthesis from cellulosic biomass.

关键词： 5-hydroxymethylftirfural hardwood softwood ferric sulphate biorefinery

Remediation of Fly Ash Dumpsites Through Bioenergy Crop Plantation and Generation: A Review

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Pedosphere 2018年第4期28卷 561-580页

作者： Madhumita ROY Roopali ROYCHOWDHURY Pritam mukherjee Department of Biotechnology Techno India University

Utilization of fly ash, a byproduct of coal combustion in thermal power plants, is a sustainable use of waste for power *** fly ash as waste in landfills/ash ponds may not only be regarded as a loss of valuable land and essential nutrients, but also pose a significant health hazard due to fine air-borne particles and leaching of heavy metals. The presence of essential macro-and micronutrients and its porosity make fly ash an excellent soil amendment for plant growth as an organic nitrogen(N) and carbon(C)supplementation. As harmful heavy metals make fly ash unsafe for agronomy, bioenergy crop plantation and energy generation from different thermochemical conversions of the biomass would be an ideal method for coal fly ash utilization through which carbon-neutral fuel can be generated from fossil fuel, thus reducing climate change impact. This review summarizes the development of bioenergy plantation and silviculture at fly ash dumpsites with an integrated phyto-bio-rhizo-mycoremediation approach and assesses utilization of the valuable biomass for thermal energy, electricity, and biofuel generation with inclusion of a SWOT analysis(a strategic technique typically used to help identify the strength, weakness, opportunities, and threat). Bioenergy crop production through integrated phytomanagement can generate billions of dollars of wealth from waste and provides a sustainable solution for fly ash management,with environmental, economic, and social benefits.

关键词： biofuel production biomass-generating crops carbon-neutral fuel health risk heavy metal land use phytoremediation soil amendment

Contribution from unresolved discrete sources to the extragalactic gamma-ray background(EGRB)

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Research in Astronomy and Astrophysics 2009年第11期9卷 1205-1214页

作者： Debbijoy Bhattacharya Parameswaran Sreekumar Reshmi mukherjee Department of Physics Indian Institute of Science Space Astronomy & Instrumentation Division ISRO Satellite Centre Barnard College Columbia University

The origin of the extragalactic gamma-ray background （EGRB） is still an open question, even nearly forty years after its discovery. The emission could originate either from truly diffuse processes or from unresolved point sources. Although the majority of the 271 point sources detected by EGRET （Energetic Gamma Ray Experiment Telescope） are unidentified, of the identified sources, blazars are the dominant candidates. Therefore, unresolved blazars may be considered the main contributor to the EGRB, and many studies have been carried out to understand their distribution, evolution and contribution to the EGRB. Considering that γ-ray emission comes mostly from jets of blazars and that the jet emission decreases rapidly with increasing jet to line-of-sight angle, it is not surprising that EGRET was not able to detect many large inclination angle active galactic nuclei （AGNs）. Though Fermi could only detect a few large inclination angle AGNs during the first three months of its survey, it is expected to detect many such sources in the near future. Since non-blazar AGNs are expected to have higher density as compared to blazars, these could also contribute significantly to the EGRB. In this paper, we discuss contributions from unresolved discrete sources including normal galaxies, starburst galaxies, blazars and off-axis AGNs to the EGRB.

关键词： galaxies active -- galaxies jets -- gamma-rays observations

A simple chemical method for the synthesis of Cu^(2+) engrafted MgAl_(2)O_(4) nanoparticles: Efficient fluoride adsorbents, photocatalyst and latent fingerprint detection

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Journal of Environmental Sciences 2020年第2期32卷 301-315页

作者： Arnab mukherjee Mrinal KAdak Prasanta Dhak Debasis Dhak Nanomaterials Research Lab Department of ChemistrySidho-Kanho-Birsha UniversityPurulia 723104India Department of Chemistry Techno India UniversityKolkata 700091India

An adaptable, energy efficient chemical process is employed to synthesize Cu^2+engrafted MgAl2O4 nanoparticles(Mg1-xCuxAl2O4, x = 0, 0.1, 0.3, 0.5 abbreviated as MCA0, MCA1, MCA3,and MCA5 respectively), using chelating ligand and the calcination temperature was determined by the thermogravimetric analysis of the precursor *** acted as good fluoride adsorbent in the presence of co-ions, different pH(2–11) via chemisorption revealed from Fourier-transform infrared spectroscopy(FTIR) and photodegraded Methylene Blue(MB).The satisfactory results were for MCA1(specific surface area 25.05 m^2/g) with 97%fluoride removal at pH 7.0 for the 10 mg/L initial fluoride concentration for 1.5 g/L adsorbent dose with 45 min contact time obeying the Langmuir isotherm model with negative thermodynamic parameters and 4 mmol of MCA3 with 98.51% photodegradation for 10-5 mol/L MB solution obeying pseudo-second-order and pseudo-first-order kinetics *** proposed photodegradation mechanism of MB was established by the FTIR and high-performance liquid chromatography(HPLC) *** nanoparticles are cubic, estimated through X-ray diffraction(XRD) and transmission electron microscopy(TEM) *** band gap energies, grain size, and the effective working pH were estimated by diffuse reflectance spectra(DRS), scanning electron microscope(SEM), and zero-point potential analysis respectively.A soil candle with MCA1 also fabricated for the household purpose and tested with some fluorinated field *** MCA3 was able to enhance the latent fingerprint on smooth surfaces.

关键词： Fluoride adsorbent Photocatalysis Mechanism Fingerprint detection Kroger-Vink notation Soil candle

Superior printed parts using history and augmented machine learning

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npj Computational Materials 2022年第1期8卷 1736-1745页

作者： Meng Jiang Tuhin mukherjee Yang Du Tarasankar DebRoy State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA

Machine learning algorithms are a natural fit for printing fully dense superior metallic parts since 3D printing embodies digital technology like no other manufacturing *** traditional machine learning needs a large volume of reliable historical data to optimize many printing variables,the algorithm is augmented with human intelligence derived from the rich knowledge base of metallurgy and physics-based *** augmentation improves the computational efficiency and makes the problem tractable by enabling the algorithm to use a small set of *** provide a verifiable quantitative index for achieving fully dense superior parts,facilitate material selection,uncover the hierarchy of important variables that affect the density,and present easy-to-use visual process *** findings can improve the quality consistency of 3D printed parts that now limit their greater industrial *** approach used here can be applied to solve other problems of 3D printing and beyond.

关键词： printing augmented consistency

Conditions for void formation in friction stir welding from machine learning

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npj Computational Materials 2019年第1期5卷 554-561页

作者： Yang Du Tuhin mukherjee Tarasankar DebRoy Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Friction stir welded joints often contain voids that are detrimental to their mechanical *** we investigate the conditions for void formation using a decision tree and a Bayesian neural *** types of input data sets including unprocessed welding parameters and computed variables using an analytical and a numerical model of friction stir welding were *** hundred and eight sets of independent experimental data on void formation for the friction stir welding of three aluminum alloys,AA2024,AA2219,and AA6061,were *** neural network-based analysis with welding parameters,specimen and tool geometries,and material properties as input predicted void formation with 83.3% *** the potential causative variables,i.e.,temperature,strain rate,torque,and maximum shear stress on the tool pin were computed from an approximate analytical model of friction stir welding,90 and 93.3%accuracies of prediction were obtained using the decision tree and the neural network,*** the same causative variables were computed from a rigorous numerical model,both the neural network and the decision tree predicted void formation with 96.6% *** these four causative variables,the temperature and maximum shear stress showed the maximum influence on void formation.

关键词： welding friction welded

Thermal conductivity of dense hcp iron:Direct measurements using laser heated diamond anvil cell

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Geoscience Frontiers 2020年第5期11卷 1755-1761页

作者： Pinku Saha Aritra Mazumder Goutam Dev mukherjee National Centre for High Pressure Studies Department of Physical SciencesIndian Institute of Science Education and Research KolkataMohanpur CampusMohanpur741246NadiaWest BengalIndia

Thermal conductivity(k)of iron is measured up to about 134 *** measurements are carried out using the single sided laser heated diamond anvil cell,where the power absorbed by a Fe metal foil at hotspot is calculated using a novel thermodynamical *** conductivity of fee(γ)-Fe increases up to a pressure of about46 *** find thermal conductivity values in the range of 70-80 Wm-1K-1(with an uncertainty of 40%),almost constant with pressure,in the hcp(e)phase of *** attribute the pressure independent k above 46 GPa to the strong electronic correlation effects driven by the electronic topological transition(ETT).We predict a value of thermal conductivity ofε-Fe of about 40±16 Wm-1K-1 at the outer core of Earth.

关键词： Laser heated diamond anvil cell Thermal conductivity High pressure effects Geodynamo