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optimization and kinetic studies for enzymatic hydrolysis and fermentation of colocynthis vulgaris Shrad seeds shell for bioethanol production

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Journal of Bioresources and Bioproducts 2021年第1期6卷 45-64页

作者： igwilo Christopher Nnaemeka Egbuna Samuel o onoh Maxwell i Asadu oChristain onyekwulu Chinelo S Department of Science Laboratory Technology Federal College of AgricultureP.M.BIshiaguEbonyi StateNigeria Department of Chemical Engineering Enugu State University of Science and Technology (ESUT)Nigeria Gregory University Uturu PMB 1012 Abia State Nigeria

The key process parameters for the hydrolysis and fermentation of Colocynthis vulgaris Shrad seeds shell(CVSSS)were optimized using the Box-Behnken Design(BBD)of Response Surface Methodology(RSM).Kinetic study was also carried *** proximate analysis of the CVSSS was done by the method of the Association of organic and Applied Chemistry(AoAC).Enzymatic hydrolysis was experimented by using Aspergillus Niger as a crude enzyme isolated from soil at sawdust dump site and screened for cellulosic *** that affected the hydrolysis of the CVSSS were screened by using the Greco-Latin square design of ***,for Saccharomyces cerevisiae,factors that affected the fermentation of the CVSSS were screened by using the same Greco-Latin square design of ***,the result of the proximate analysis revealed that the CVSSS had 73.54%cellulose which could be converted to *** was established that temperature,pH and time had significant effect on hydrolysis,while the optimum results were obtained at 46.8℃,3.32 d,5.68 and 59.87%for temperature,time,pH and glucose yield,***,yeast dosage,pH and time had significant effect on fermentation,while the optimum results from optimization were found to be 33.58℃,7.0,3.55 d,1.65 g per 50 mL and 25.6%for temperature,pH,time,yeast dosage and ethanol yield,*** kinetics of both the enzymatic hydrolysis and fermentation agreed with the Michealis-Menten kinetic model with the correlation coefficients(R^(2))of 0.9708 and 0.8773,***,from the error analysis,the experimental and predicted values had a very good relationship as described by Michaelis-Menten model.

关键词： Ethanol Melon(Egusi)seed shell Hydrolysis Fermentation optimization Kinetics

Generalized Jackiw-Teitelboim gravity in presence of Block brane-like models

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Chinese Physics C 2022年第12期46卷 258-270页

作者： i.Andrade D.Bazeia A.S.Lobão Jr. R.Menezes Departamento de Física Universidade Federal da Paraíba58051-970 João PessoaPBBrazil Escola Técnica de Saúde de Cajazeiras Universidade Federal de Campina Grande58900-000 CajazeirasPBBrazil Departamento de Ciências Exatas Universidade Federal da Paraíba58297-000 Rio TintoPBBrazil

We investigate generalized Jackiw-Teitelboim gravity,coupling the dilaton field with two scalar matter *** obtain the equations of motion for the fields and investigate a linear perturbation of the solutions in *** study two specific situations that allow for analytic solutions with topological behavior and check how the dilaton field,the warp factor and the Ricci scalar *** particular,we show how the parameters can be used to modify the structure of the ***,the perturbations are,in general,described by intricate coupled differential equations,but in some specific cases,we can construct the corresponding zero modes analytically.

关键词： Dilaton 2D gravity Multifield

Bistability in Coupled oscillators Exhibiting Synchronized Dynamics

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Communications in Theoretical Physics 2010年第5期53卷 815-824页

作者： o.i.olusola U.E.Vincent A.N.Njah J.A.olowofela Department of Physics University of Agriculture Department of Physics Lancaster University institut fur Theoretische Physik Technische Universitt Clausthal Department of Physics Olabisi Onabanjo University

We report some new results associated with the synchronization behavior of two coupled double-well Duffing oscillators （DDos）. Some sufficient algebraic criteria for global chaos synchronization of the drive and response DDos via linear state error feedback control are obtained by means of Lyapunov stability theory. The synchronization is achieved through a bistable state in which a periodic attractor co-exists with a chaotic attractor. Using the linear perturbation analysis, the prevalence of attractors in parameter space and the associated bifurcations are examined. Subcritical and supercritical Hopf bifurcations and abundance of Arnold tongues -- a signature of mode locking phenomenon are found.

关键词： chaos synchronization Duffing oscillator bistability Lyapunov stability theory

Variability in distribution of major and trace elements in Lower Eocene siliceous sections of the Transuralian Region, Russia

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Acta Geochimica 2019年第2期38卷 262-276页

作者： P.V.Smirnov A.o.Konstantinov G.A.Batalin B.i.Gareev Tyumen industrial University Technische Universit?t Clausthal Kazan Federal University

This paper presents lithologic and geochemical data from the sequence of the Eocene irbit formation siliceous rocks(Transuralian Region) outcropping in a quarry in the irbit deposit(thickness of 15 m) and in a large natural outcrop, Belaya Gorka(thickness of 13 m). The data show that both outcrops are composed of diatomites and clayey diatomites, both characterized by a certain degree of lithologic heterogeneity around their chemical,granulometric, and mineralogical compositions;microstructural features; and degree of diatom preservation. The values of indices important for the classification of siliceous rocks and determination of prospects for their industrial application—Sio_2, Al_2o_3, Fe_2o_3, and clay fraction content—ranged from 66% to 77%, 7% to 14%,3.00% to 5.60%, and 23% to 50%, respectively. in all studied lithologic varieties, element abundances of V, Cr,Mn, Co, Ni, Cu, Zn, Ga, Ge, and Sb were two to three times higher than their respective abundances in the Earth's crust. This is probably related to these elements' involvement in the biological cycle and favorable conditions for transport. Rb, Cs, Ba, and Sr, as well as rare earth elements,are considered the most reliable indicators of lithologic and geochemical subdivision of a sequence of siliceous rocks,as they are associated mainly with clayey minerals. Variations in these indicators have recorded, with great probability, even short-term cycles and semi-cycles of silicasedimentation in the Transuralian Region, as well as tectonic regime and involvement of terrigenous influx.

关键词： Diatomite Clayey diatomite irbit formation Eocene Geochemical variability

TDS-Eh graph analysis： a new water quality index and rural water supply implications of a river affected by mining in south-eastern Nigeria

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Frontiers of Earth Science 2012年第1期6卷 66-74页

作者： i.C.EZEKWE A.o.AiSUBEoGUN G.N.CHiMA E.oDUBo Department of Geography and Environmental Management Niger Delta UniversityWilberforce IslandPMB 071Yenegoa Nigeria Department of Geography and Planning Abia State UniversityPMB 2000UturuNigeria

The ivo River Basin of south-eastern Nigeria is a water scarce and mining region, which suffers from water scarcity. The influence of mining activities on the quality of the ivo River and its capacity for community water supply was investigated. Also the efficacy of TDS-Eh graph in explaining water quality was presented. Results indicated that the TDS-Eh graph highlights subtle chemical relationships which control water quality and provide a simple but generic pollution index for rapid water quality assessment. it was also discovered that the ivo River could become an adequate alternative to groundwater as a source of rural water supply in the study area with an estimated average daily discharge of 6726000L and a rural population of less than 200000 persons. The ivo River meets the WHo drinking water standards in 20 physico- chemical water quality parameters （pH, temperature, conductivity, turbidity, salinity, TDS, Eh, alkalinity, chloride, nitrate, sulfate, phosphate, calcium, magnesium, iron, manganese, zinc, lead and cadmium） analyzed and can therefore （with little treatment） provide up to 133.4% of average community water demand and 83.8% of maximum community water demand. The. impact of mining on ivo River quality was found to have been moderated by the presence of carbonate rocks which may have enhanced the precipitation of heavy metals from the river.

关键词： TDS-Eh graph water quality mining ruralwater supply ivo River Nigeria

Halophily reloaded:new insights into the extremophilic life-style of Wallemia with the description of Wallemia hederae ***

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Fungal Diversity 2016年第1期76卷 97-118页

作者： Sašo Jančič Polona Zalar Dragi Kocev Hans-Josef Schroers Sašo Džeroski Nina Gunde-Cimerman Department of Biology Biotechnical FacultyJamnikarjeva 101SI-1000 LjubljanaSlovenia Department of Knowledge Technologies Jožef Stefan InstituteJamova cesta 39SI-1000 LjubljanaSlovenia Agricultural institute of Slovenia Hacquetova 17p.p.2553SI-1000 LjubljanaSlovenia Centre of Excellence for integrated Approaches in Chemistry and Biology of Proteins(CiPKeBiP) Jamova cesta 39SI-1000 LjubljanaSlovenia

Wallemia comprises air-and food-borne,mycotoxigenic contaminants including the halophilic ***,xerotolerant *** and xerophilic *** isolates are easily overlooked and only a comparably small number of strains have been deposited in culture collections so *** order to better understand the natural distribution of Wallemia *** to encounter their natural habitats,we tested more than 300 low-water-activity substrates and 30 air samples from a wide geographical *** isolated more than 150 new Wallemia *** sebi and *** were isolated mostly from hypersaline water,low-water-activity foods,plant materials and *** muriae is the dominant Wallemia species in the air of natural and human influenced environments in *** isolates of *** were obtained from hypersaline environments such as brine,salt crystals,salty foods and MgCl_(2)-rich bitterns,and from the air of hay barns in *** halotolerant strains were recognised as a hitherto un-described species Wallemia hederae,the phylogenetic sister of the halophilic *** *** in-vitro growth on media that contain the chaotropic salt MgCl_(2).Wallemia ichthyophaga can grow in liquid medium enriched with 2 M MgCl_(2).Never before has a microorganism been grown on comparably high MgCl_(2) *** of the activity of a wide range of extracellular enzymes in the presence of NaCl also suggested that Wallemia iswell-adapted to substrates with a reduced water activity.

关键词： Chaophiles Ecophysiology Extracellular enzymes Exudates Machine learning Taxonomy

Two-dimensional control of light with light on metasurfaces

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Light(Science & Applications) 2016年第1期5卷 826-830页

作者： Maria Papaioannou Eric Plum João Valente Edward TF Rogers Nikolay i Zheludev optoelectronics Research Centre and Centre for Photonic Metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK institute for Life Sciences University of SouthamptonHighfieldSouthampton SO171BJUK The Photonics institute and Centre for Disruptive Photonic Technologies Nanyang Technological UniversitySingapore 637371Singapore

The ability to control the wavefront of light is fundamental to focusing and redistribution of light,enabling many applications from imaging to *** interaction on highly nonlinear photorefractive materials is essentially the only established technology allowing the dynamic control of the wavefront of a light beam with another beam of light,but it is slow and requires large optical *** we report a proof-of-principle demonstration of a new technology for two-dimensional(2D)control of light with light based on the coherent interaction of optical beams on highly absorbing plasmonic *** illustrate this by performing 2D all-optical logical operations(AND,XoR and oR)and image *** approach offers diffractionlimited resolution,potentially at arbitrarily-low intensity levels and with 100 THz bandwidth,thus promising new applications in space-division multiplexing,adaptive optics,image correction,processing and recognition,2D binary optical data processing and reconfigurable optical devices.

关键词： all-optical data processing all-optical image processing coherent control metasurfaces

A new interpretation for the origin of the Norilsk type PGE-Cu-Ni sulfide deposits

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Geoscience Frontiers 2011年第4期2卷 583-591页

作者： V.i.Starostin o.G.Sorokhtin Geological Faculty Lomonosov Moscow State UniversityMoscow119991 Russia

The origin of PGE—Cu—Ni sulfide deposits of Norilsk and Talnakh located in the northwest flank of the Triassic basalt trap formation of Siberia is *** is shown that ore elements of these deposits（probably,except Fe） are derived from the crust rather than from the *** entered the basalts owing to a remobilization（recycling） of ore elements from the Paleoproterozoic sediments and from the rocks of the Siberian platform＇s *** criteria for similar deposits are as follows：（1） a presence of a large Paleoproterozoic aulacogen and a related magmatic sulfide Cu—Ni mineralization;（2） a confinement of perspective areas to troughs associated with long-lived deep fault zones：（3） association with mobile orogenic belts,island-arc systems and tectonomagmatic activation zones;（4） temporal association with boundaries of global periods characterized by active processes of continental breakup and large-scale trap magmatism.A combination of several factors（the first one is obligatory） is favorable for the discovery of a large ore body.

关键词： PGE-Cu-Ni sulfide deposits Siberian traps Paleoproterozoic Recycling of ore elements

Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−Noyce−Shockley recombination mechanism

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Journal of Semiconductors 2024年第8期45卷 25-33页

作者： Fedor i.Manyakhin Dmitry o.Varlamov Vladimir P.Krylov Lyudmila o.Morketsova Arkady A.Skvortsov Vladimir K.Nikolaev Dinamics Strength of Machines and Resisance of MaterialsMoscow Polytechnic UniversityRussia Biomedical and Electronic Means and Technologies Vladimir State UniversityRussia Computer-Aided Design and Engineering National University of Science and Technology"MISiS"Russia

Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their *** technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.

关键词： light-emitting diodes with quantum wells voltage−current relation nonideality factor recombination mechanism Sah−Noyce−Shockley model