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Sequential decay analysis of^(235)U(n^(th),f)reaction using fragmentation approach

Chinese Physics C 2024年第6期48卷 145-154页

作者： Nitin Sharma Ashutosh Kaushik Manoj K.Sharma School of Physics and Materials science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

Numerous experimental and theoretical observations have concluded that the probability of the three fragment emission(ternary fission)or binary fission increases when one proceeds towards the heavy mass region of nuclear periodic *** factors affect fragment emission,such as the shell effect,deformation,orientation,and fissility *** and ternary fissions are observed for both ground and excited states of the *** collinear cluster tripartition(CCT)channel of the^(235)U(n^(th),f)reaction is studied,and we observe that the CCT may be a sequential or simultaneous emission *** date,different approaches have been introduced to study the CCT process as a simultaneous or sequential process,but the decay dynamics of these modes have not been not fully *** the three fragments of the sequential process and exploring their related dynamics using an excitation energy dependent approach would be of further ***,in this study,we investigate the sequential decay mechanism of the^(235)U(n^(th),f)reaction using quantum mechanical fragmentation theory(QMFT).The decay mechanism is considered in two steps,where initially,the nucleus splits into an asymmetric *** the second step,the heavy fragment obtained in the first step divides into two *** I analysis is conducted by calculating the fragmentation potential and preformation probability for the spherical and deformed choices of the decaying *** most probable fragment combination of stage I are identified with respect to the dips in the fragmentation structure and the corresponding maxima of the preformation probability(P0).The light fragments of the identified decay channels(obtained in step I)agree closely with the experimentally observed *** excitation energy of the decay channel is calculated using an iteration *** excitation energy is shared using an excitation energy dependent level density *** obtained excitation

关键词： fission cluster radioactivity ternary fission spontaneous fission cluster model total kinetic energy preformation probability

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Comparative evaluation of physico-chemical characteristics of biopolyesters P（3HB） and P（3HB-co-3HV） produced by endophytic Bacillus cereus RCL 02

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Frontiers in Biology 2018年第4期13卷 297-308页

作者： Ritupama das Nayan Ranjan Saha Arundhati Pal Dipankar Chattopadhyay Amal Kanti Paul Microbiology Laboratory Department of Botany University of Calcutta 35 Ballygunge Circular Road Kolkata 700019 West Bengal India department of Polymer science and technology University of Calcutta 92 A. P. C. Road KoIkata 700009 West Bengal India department of Botany Serampore College 9 William Carey Road Serampore Hooghly 712201 West Bengal India

BACKGROUND： Bacteria endogenously residing within the plant tissues have attracted significant attention for production of biopolyester, polyhydroxyalkanoates （PHAs）. Bacillus cereus RCL 02 （MCC 3436）, a leaf endophyte of oleaginous plant Ricinus communis L. accumulates 81% poly（3-hydroxybutyrate） [P（3HB）] of its cell dry biomass when grown in mineral salts （MS） medium. METHODS： The copolymer production efficiency of B. cereus RCL 02 was evaluated in valeric acid supplemented MS medium under biphasic cultivation condition. The copolymer so produced has been compared with the P（3HB） isolated from RCL 02 in terms of thermal, mechanical and chemical properties. RESULTS： Valeric acid supplementation as co-substrate in the medium has led to the production of copolymer of 3- hydroxybutyrate （3HB） and 3-hydroxyvalerate （3HV） [P（3HB-co-3HV）] with 14.6 mol% 3HV. The identity of the polymers has been confirmed by X-ray diffraction （XRD） analysis, Fourier transform infrared （FTIR） and nuclear magnetic resonance （NMR） spectroscopic studies. Thermogravimetric analysis （TGA） revealed that P（3HB） and P（3HB-co-3HV） films degraded at 278.66℃ and 273.49℃, respectively. The P（3HB-co-3HV） showed lower melting temperature （165.03℃） compared to P （3HB）（170.74℃） according to differential scanning calorimetry （DSC）. Incorporation of 3HV monomers decreased the tensile strength （21.52 MPa）, tensile modulus （0.93 GPa）, storage modulus （E＇）（0.99 GPa） and increased % elongation at break （12.2%） of the copolyester. However, P（3HB） showed better barrier properties with lower water vapor transmission rate （WVTR） of 0.55 g-mil/100 in2/24 h. CONCLUSION： These findings emphasized exploration of endophytic bacterial strain （RCL 02） to produce biodegradable polyesters which might have significant potential for industrial application.

关键词： poly(3-hydroxybutyrate) poly(3-hydroxybutyrate-co-3-hydroxyvalerate) biodegradable polyester Bacillus cereus endophytic bacteria

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Statistical optimization and formulation of microalga cultivation medium for improved omega 3 fatty acid production

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Systems Microbiology and Biomanufacturing 2022年第2期2卷 369-379页

作者： Aswathy Udayan Nidhin Sreekumar Muthu Arumugam Microbial Processes and technology Division National Institute for Interdisciplinary Science and Technology(NIIST)CSIRIndustrial EstatePappanamcodeThiruvananthapuramKerala 695019India Academy of Scientifc and Innovative research(AcSIR) Ghaziabad 201002India Accubits Invent Accubits Technologies Inc.ThiruvananthapuramKerala 695004India

Microalgae are considered a rich source of high-value metabolites with an array of nutraceutical and pharmaceutical *** strategies have been developed for cultivating microalgae at large-scale photobioreactors but high cost and low productivity are the major *** the composition of media for the cultivation of microalgae to induce biomass production and high-value metabolite accumulation has been considered as an important factor for sustainable product *** this study,the efect of plant growth regulators together with basal microalgal cultivation medium on biomass,total lipid,and EPA production was studied using the Plackett–Burman model and Response surface *** traditional one-factor-at-a-time optimization approach is laborious,time-consuming,and requires more experiments which makes the process and analysis more *** Designed PB model was found to be signifcant for biomass(396 mg/L),lipid(254 mg/L),and EPA(5.6%)production with a P valuenew media using RSM to achieve the goal and the signifcant variables selected were NaNO_(3),NaH_(2)PO_(4),and IAA and was found to be signifcant with 16.72%EPA production with a biomass production of 893 mg/L with a P value<*** formulated medium can be used in large-scale cultivation systems which can enhance biomass production as well as the omega 3 fatty acid production in marine microalgae Nannochloropsis oceanica.

关键词： Microalgae Omega 3 fatty acids EPA Plackett–Burman Response surface methodology Plant growth regulators

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SINGLE SERVER QUEUES WITH A BATCH MARKOVIAN ARRIVAL PROCESS AND BULK REnewAL OR NON-REnewAL SERVICE

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Journal of Systems science and Systems Engineering 2015年第3期24卷 337-363页

作者： A.D.Banik School of Basic sciences Indian Institute of Technology

We first consider an infinite-buffer single server queue where arrivals occur according to a batch Markovian arrival process （BMAP）. The server serves customers in batches of maximum size ＇b＇ with a minimum threshold size ＇a＇. The service time of each batch follows general distribution independent of each other as well as the arrival process. The proposed analysis is based on the use of matrix-analytic procedure to obtain queue-length distribution at a post-departure epoch. Next we obtain queue-length distributions at various other epochs such as, pre-arrival, arbitrary and pre-service using relations with post-departure epoch. Later we also obtain the system-length distributions at post-departure and arbitrary epochs using queue-length distribution at post-departure epoch. Some important performance measures, like mean queue-lengths and mean waiting times have been obtained Total expected cost function per trait time is also derived to determine the locally optimal values of a and b. Secondly, we perform similar analysis for the corresponding infinite-buffer single server queue where arrivals occur according to a BMAP and service process in this case follows a non-renewal one, namely, Markovian service process （MSP）.

关键词： Bulk service (a b)-rule system-length distribution infinite-buffer queue batch Markovian arrival process Markovian service process matrix-analytic procedure cost control cloud computing

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Study of various ground state decay mechanisms of Actinide nuclei

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Chinese Physics C 2023年第10期47卷 197-212页

作者： Chahat Jindal Nitin Sharma Manoj K.Sharma School of Physics and Materials science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

The special property of the actinide mass region is that nuclei belonging to this group are radioactive and undergo different ground state processes,such as alpha decay,cluster radioactivity(CR),heavy particle radioactivity(HPR),and spontaneous fission(SF).In this study,the probable radioactive decay modes of the heavy mass region(Z=89−102)are studied within the framework of the preformed cluster model(PCM).In the PCM,the radioactive decay modes are explored in terms of the preformation probability(P0)and penetration probability(P)at the turning point Ra,where the penetration of fragments is initiated[Ra=RT(touching state)+ΔR(neck length parameter)].First,the alpha decay half-lives are calculated for light and heavy nuclei,and Ra points are obtained by optimizing the neck length *** Ra points are further employed to fix the Q-value dependent turning point(Ra(Q)).Then,using the(Ra(Q))relation,the decay half-lives are computed,and the calculated results are compared with the available theoretical and experimental *** isotopical trend of P0 and P is studied with respect to the mass number of the parent and daughter nucleus,*** CR and HPR channels are also explored,and a comparison of calculated data is conducted with the available *** analysis of the fragmentation potential and preformation probability is carried out for alpha decay and *** mass distribution of the nuclei is studied as a function of fragment mass(A2)by considering the spherical and hot-compact deformation of the decaying ***,the most probable fission fragments are identified using the fragmentation structure,and the corresponding fission fragment total kinetic energy of the identified fragments is calculated and compared with available data,wherever applicable.

关键词： Alpha decay cluster radioactivity spontaneous fission heavy particle radioactivity ground state decay

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Mesoporous carbon adsorbents from melamine–formaldehyde resin using nanocasting technique for CO_2 adsorption

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Journal of Environmental sciences 2015年第6期27卷 238-248页

作者： Chitrakshi Goel Haripada Bhunia Pramod K. Bajpai department of Chemical Engineering Thapar University

Mesoporous carbon adsorbents, having high nitrogen content, were synthesized via nanocasting technique with melamine-formaldehyde resin as precursor and mesoporous silica as template. A series of adsorbents were prepared by varying the carbonization temperature from 400 to 700°C. Adsorbents were characterized thoroughly by nitrogen sorption, X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, thermogravimetric analysis（TGA）, elemental（CHN） analysis, Fourier transform infrared（FTIR） spectroscopy and Boehm titration. Carbonization temperature controlled the properties of the synthesized adsorbents ranging from surface area to their nitrogen content, which play major role in their application as adsorbents for CO2 *** nanostructure of these materials was confirmed by XRD and TEM. Their nitrogen content decreased with an increase in carbonization temperature while other properties like surface area, pore volume, thermal stability and surface basicity increased with the carbonization temperature. These materials were evaluated for CO2 adsorption by fixed-bed column adsorption experiments. Adsorbent synthesized at 700°C was found to have the highest surface area and surface basicity along with maximum CO2 adsorption capacity among the synthesized adsorbents. Breakthrough time and CO2 equilibrium adsorption capacity were investigated from the breakthrough curves and were found to decrease with increase in adsorption temperature. Adsorption process for carbon adsorbent-CO2 system was found to be reversible with stable adsorption capacity over four consecutive adsorption-desorption cycles. from three isotherm models used to analyze the equilibrium data, Temkin isotherm model presented a nearly perfect fit implying the heterogeneous adsorbent surface.

关键词： Carbon Nanocasting Mesoporous CO2 adsorption Isotherm

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Revisiting band structures in^(118)Xe nucleus via in-beamγ-ray spectroscopy

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中国物理C:英文版 2023年第8期47卷 22-38页

作者： A.Pandey R.Bhushan A.Rohilla C.Majumder H.P.Sharma S.Chakraborty R.P.Singh S.Muralithar Yashraj K.Katre B.Rohila Subodh A.Kumar I.M.Govil S.Jehangir N.Rather G.H.Bhati A.A.Wani J.A.Sheikh S.K.Chamoli department of Physics and Astrophysics University of DelhiNew Delhi-110007India Institute of Space sciences Shandong UniversityWeihai-264209China department of Physics Indian Institute of Technology BombayMumbai-400076India department of Physics Institute of ScienceBanaras Hindu UniversityVaranasi-221005India Variable Energy Cyclotron Centre Kolkata-700064India Inter University Accelerator Centre Aruna Asaf Ali MargNew Delhi-110067India department of Physics Punjab UniversityChandigarh-160014India department of Physics Islamic University of Science and TechnologyJammu and Kashmir-192122India Higher Education department Government of Jammu and KashmirSrinagarJ&K-180001India department of Physics University of KashmirSrinagar-190006India

The neutron deficient Xe nuclei with A≈120 are predicted to have strong octupole correlation at low *** the present study,an attempt was made to improve upon the level scheme and also to examine the signatures of octupole correlation in^(118)xe via high spin γ-ray *** spin states in^(118)Xe have been populated via the^(93)Nb(^(28)Si,p2n)^(118)Xe fusion-evaporation reaction at a beam energy of 115 MeV provided by the 15 UD pelletron accelerator facility at IUAC,new *** the experiment,seven newγ-transitions have been found and placed appropriately in the level scheme.A theoretical study using the triaxial projected shell model(TPSM)approach suggests that the first bandcrossing is due to the alignment of two neutrons,and a parallel band tracking the yrast configuration is the γ-band built on the two-quasiparticle *** E1 transition rates measured between opposite parity bands involving vh_(11/2)and vd_(5/2)orbitals having△j=△l=3 indicate the presence of octupole correlation in this nucleus.

关键词： octupole correlation γ-ray spectroscopy TPSM calculations bandcrossing

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Nanomaterials for the abatement of cadmium (Ⅱ) ions from water/ wastewater

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Nano research 2019年第7期12卷 1489-1507页

作者： Kumar Vikrant Vanish Kumar Kowsalya Vellingiri Ki-Hyun Kim department of Civil and Environmental Engineering Hanyang University222 Wangsimni-roSeoul 04763Republic of Korea National Agri-Food Biotechnology Institute (NABI) S.A.S. NagarPunjab 140306India Environmental and Water Resources Engineering Division Department of Civil Engineering IIT MadrasChennai 600036India

The rapid rise of modern industry is the source of unchecked effluents containing many pernicious heavy metals (e.g.,cadmium).To rehabilitate the ecology,food resources,and health of humans and animals,various conventional methodologies are being used in wastewater treatment facilities for the abatement of ***,the development of advanced,economical,and efficient adsorbents is needed because of the many shortcomings of conventional methods (e.g.,high cost,intensive operation,and inefficiency).Recent advancements in materials science and chemistry have introduced the use of nanomaterials,which possess very high specific surface areas and multiple functionalities,for the removal of specific targets such as *** review explores the recent developments and trends in nanomaterial adsorption technology for the mitigation of *** paper further surveys the present obstacles and future opportunities for the advancement of nanomaterial-based technologies in the area of water treatment.

关键词： nanomaterials cadmium adsorption pollution control water purification heavy metal

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Sb_(2)Te_(3)/graphite nanocomposite: A comprehensive study of thermal conductivity

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Journal of Materiomics 2021年第3期7卷 545-555页

作者： Subarna das P.Singha V.A.Kulbachinskii V.G.Kytin Gangadhar das S.Janaky A.K.Deb Sudip Mukherjee A.Maignan S.Hebert R.Daou Chandrabhas Narayana S.Bandyopadhyay Aritra Banerjee department of Physics University of Calcutta92 A P C RoadKolkata700009India Laboratoire de Cristallographie et sciences des Materiaux(CRISMAT) Normandie UniversiteUMR6508 CNRSENSICAENUNICAEN14000CaenFrance department of Low Temperature Physics and Superconductivity Physics FacultyM.V.Lomonosov Moscow State University119991MoscowRussia Moscow Institute of Physics and technology 141700DolgoprudnyMoscow RegionRussia Chemistry and Physics of Materials Unit Jawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.OBangalore560064India department of Physics Raiganj UniversityUttar DinajpurWest Bengal733134India UGC-DAE Consortium for Scientific research Mumbai CentreR-5 ShedBARC CampusTrombayMumbai400008India Center for research in Nanoscience and Nanotechnology University of CalcuttaJD-2Sector-IIISaltlakeKolkata700106India

Thermoelectric performance largely depends on the reduction of lattice thermal conductivity(kL).The study of the thermal conductivity(k)of a Sb_(2)Te_(3)/graphite nanocomposite system demonstrates-40%reduction in kL with graphite incorporation.A plausible explanation of intrinsic low kL observed in Sb_(2)Te_(3) based system is presented by modeling experimental specific heat(Cp)*** spectroscopy measurement combined to X-Ray diffraction data confirms the presence of graphite as separate phase in the composite *** is found that phonon scattering dominates heat transport mechanism in the nanostructured Sb_(2)Te_(3)/graphite *** reduction in kL is accomplished by intensifying scattering rate of phonons via various *** introduces effective scattering sources,i.e.,defects of different dimensionalities in synthesized nanocomposite ***,graphite mediates phonon-phonon coupling and enhances lattice anharmonicity,which causes an intrinsic scattering of phonons with all frequencies in the Sb_(2)Te_(3)/graphite nanocomposite *** density and phonon anharmonicity of the synthesized samples are estimated from in depth analysis of temperature dependent synchrotron powder diffraction and Raman spectroscopic *** value as low as 0.8 W m1 K1 at 300 K,achieved with graphite dispersion in Sb_(2)Te_(3) based composite system makes the present comprehensive study an interesting concept to be developed in thermoelectric materials.

关键词： Thermoelectric systems Thermal conductivity Phonons X-ray powder diffraction Raman spectroscopy Specific heat measurements

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The amazing potential of fungi:50 ways we can exploit fungi industrially

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Fungal Diversity 2019年第4期97卷 1-136页

作者： Kevin D.Hyde Jianchu Xu Sylvie Rapior Rajesh Jeewon Saisamorn Lumyong Allen Grace T.Niego Pranami D.Abeywickrama Janith V.S.Aluthmuhandiram Rashika S.Brahamanage Siraprapa Brooks Amornrat Chaiyasen K.W.Thilini Chethana Putarak Chomnunti Clara Chepkirui Boontiya Chuankid Nimali I.de Silva Mingkwan Doilom Craig Faulds Eleni Gentekaki Venkat Gopalan Pattana Kakumyan Dulanjalee Harishchandra Hridya Hemachandran Sinang Hongsanan Anuruddha Karunarathna Samantha C.Karunarathna Sehroon Khan Jaturong Kumla Ruvishika S.Jayawardena Jian-Kui Liu Ningguo Liu Thatsanee Luangharn Allan Patrick G.Macabeo Diana S.Marasinghe Dan Meeks Peter E.Mortimer Peter Mueller Sadia Nadir Karaba N.Nataraja Sureeporn Nontachaiyapoom Meghan O’Brien Watsana Penkhrue Chayanard Phukhamsakda Uma Shaanker Ramanan Achala R.Rathnayaka Resurreccion B.Sadaba Birthe Sandargo Binu C.Samarakoon Danushka S.Tennakoon Ramamoorthy Siva Wasan Sriprom T.S.Suryanarayanan Kanaporn Sujarit Nakarin Suwannarach Thitipone Suwunwong Benjarong Thongbai Naritsada Thongklang Deping Wei S.Nuwanthika Wijesinghe Jake Winiski Jiye Yan Erandi Yasanthika Marc Stadler Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming 650201YunnanPeople’s Republic of China Center of Excellence in Fungal research Mae Fah Luang UniversityChiang Rai 57100Thailand School of science Mae Fah Luang UniversityChiang Rai 57100Thailand World Agroforestry Centre East and Central AsiaKunming 650201YunnanPeople’s Republic of China Mushroom research Foundation 128 M.3 Ban Pa Deng T.PaPaeA.Mae TaengChiang Mai 50150Thailand Aix Marseille Université INRAUMR1163 BBF13288 Marseille Cedex 09France Beijing Key Laboratory of Environment Friendly Management on Fruit Diseases and Pests in North China Center of Plant and Environment ProtectionBeijing Academy of Agriculture and Forestry SciencesBeijing 100097People’s Republic of China Center of Chemical Innovation for Sustainability Mae Fah Luang UniversityTasudMuangChiang Rai 57100Thailand Center of Excellence in Microbial Diversity and Sustainable Utilization Faculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand Center for Mountain Ecosystem Studies Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanPeople’s Republic of China Institute of Fungal research School of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China department Microbial Drugs Helmholtz Centre for Infection Researchand German Centre for Infection Research(DZIF)partner site Hannover-BraunschweigInhoffenstrasse 738124 BrunswickGermany department of Biology Faculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand department of Chemistry and Biochemistry The Ohio State UniversityColumbusOH 43210USA department of Chemistry University of Science and TechnologyBannuKhyber PakhtunkhwaPakistan department of Crop Physiology University of Agricultural SciencesGKVKBengaluruKarnataka 560065India department of Entomology and Plant Pathology Faculty of AgricultureChiang Mai Univers

Fungi are an understudied,biotechnologically valuable group of *** to the immense range of habitats that fungi inhabit,and the consequent need to compete against a diverse array of other fungi,bacteria,and animals,fungi have developed numerous survival *** unique attributes of fungi thus herald great promise for their application in biotechnology and ***,fungi can be grown with relative ease,making production at scale *** search for fungal biodiversity,and the construction of a living fungi collection,both have incredible economic potential in locating organisms with novel industrial uses that will lead to novel *** manuscript reviews fifty ways in which fungi can potentially be utilized as *** provide notes and examples for each potential exploitation and give examples from our own work and the work of other notable *** also provide a flow chart that can be used to convince funding bodies of the importance of fungi for biotechnological research and as potential *** have provided the world with penicillin,lovastatin,and other globally significant medicines,and they remain an untapped resource with enormous industrial potential.

关键词： Biocontrol Biodiversity Biotechnology Food Fungi Mushrooms

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