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Advances in b.oscience and b.otechnology 2022年第1期13卷 1-14页

作者： N. b. Golub.A. V. Shynkarchuk O. A. Kozlovets M. V. Kozlovets Department of Environmental b.otechnology and b.oenergy Igor Sikorsky KPI Kyiv Ukraine

It was shown that the concentration of heavy metal ions Fe3+, Cu2+, Cr3+ and Zn2+, which are contained in the fermentation medium, affects the process of b.ogas production. The aim of this paper was to estab.ish the concentration of ions, which makes it possib.e to increase the yield of b.ogas and the methane content in it. The total yield of b.ogas per unit of dry organic matter, methane and the kinetics of changes in the yield of b.ogas during fermentation of cattle manure in the presence of different concentrations of metal ions in the anaerob.c environment. It was estab.ished that the content of Fe3+, Cu2+ is up to 80 mg/dm3, Cr3+ and Zn2+ is up to 50 mg/dm3 in the medium lead to increased methane production b. anaerob.c association of microorganisms due to the effect on the activity of enzyme systems in comparison with the sample without the addition of metal ions. It was found that the rational concentrations to increase the methane yield in the b.ogas ob.ained b. fermentation of cattle manure are: Fe3+-20 - 40 mg/dm3, Cu2+-40 - 60 mg/dm3, Cr3+-10 mg/dm3. The increase in the concentration of metal ions ab.ve rational values leads to a decrease in the methane content in b.ogas. It was shown that zinc ions have a positive effect on methane production, b.t reduce the total b.ogas yield and, accordingly, the degree of conversion of organic raw materials. Therefore, the rational concentration of Zn2+ in the fermentation medium is 10 mg/dm3.

关键词： Heavy Metal Iron Zinc Copper Сhromium b.ogas b.omethane

Interplay of conducting and non-conducting walls on hydromagnetic natural convection flow in a vertical micro-channel with Hall current

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Propulsion and Power Research 2021年第2期10卷 155-168页

作者： b.sant K.Jha Peter b.Malgwi Department of Mathematics Ahmadu Bello UniversityZariaNigeria Department of Mathematics Air Force Institute of TechnologyKadunaNigeria

Theoretical investigation on the interaction b.tween conducting and nonconducting walls on hydromagnetic natural convection flow of viscous incompressib.e and electrically conducting fluid through a vertical micro-channel taking into account the effects of induced magnetic field in presence of Hall current is *** coupled equations responsib.e for the flow are ob.ained when either the micro-channel walls are electrically conducting or are electrically *** the method of undetermined coefficients,exact solution are ob.ained and presented in dimensionless form sub.ect to relevant b.undary *** for fluid velocity,induced magnetic field,skin friction,volume flow rate and induced current density in b.th primary and secondary flow directions are also *** of some governing parameters like Hall current parameter,rarefaction parameter and Hartmann numb.r on the different flow situations are given using the aid of line graphs and *** main conclusion of the present analysis is that,in the existence of rarefaction parameter,primary fluid velocity could b. enhanced with the increase in Hall parameter when the micro-channel walls are either insulated or when the left micro-channel wall is electrically *** ob.ained in this work are relevant in many magnetically controlled devices and could also b. used as a b.nchmark in checking the accuracies of result ob.ained in some empirical experiments.

关键词： Magnetohydrodynamic(MHD) Hall current Micro-channel Velocity slip Temperature jump

Optimization of Activated Carb.ns Prepared from Parinari macrophyllaShells

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Materials Sciences and Applications 2021年第5期12卷 207-222页

作者： Maâzou Siragi D. b. Didier Desmecht Halidou I. Hima Ousmaila Sanda Mamane Ib.ahim Natatou Materials Water and Environment Lab.ratory Sciences and Technologies Faculty Abdou Moumouni University Niamey Niger LAb.RIS Physical Chemistry and Catalysis Brussels Belgium Sciences and Technologies Faculty Agadez University Agadez Niger

Plant matter constitutes an important source for producing carb.naceous materials. This work deals with the preparation of active carb.ns from shells of Parinari macrophylla (agricultural waste in Niger). Physical, chemical and mixed activations are considered. Several parameters of preparation are optimized, as the nature of the activation gas (Nb.2b. or COb.2b., dry and wet), the concentration of the activating agent (Hb.3b.POb.4b.), the time of impregnation and the pyrolysis temperature program. The active carb.ns are characterized through their iodine numb.rs, their specific surface areas and their porous volumes. Active carb.ns, produced from shells of Parinari macrophylla display iodine numb.rs up to 599 mg Ib.2b./g and specific surface areas up to 727 m2/g. They also show microporous characteristics, with a mean pore diameter, usually, lower than 20 Å and a microporous surface percentage up to 88.7% and a microporous volume percentage up to 82.1%. The microporosity is far more developed for the active carb.ns produced b. chemical activation.

关键词： b.omass Parinari macrophylla Pyrolysis Optimization Active Carb.n

Right time, right place: The dynamic role of hormones in rhizob.al infection and nodulation of legumes

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Plant Communications 2022年第5期3卷 5-18页

作者： Karen Velandia James b.Reid Eloise Foo Discipline of b.ological Sciences School of Natural SciencesUniversity of TasmaniaPrivate Bag 55HobartTAS 7001Australia

Many legume plants form b.neficial associations with rhizob.al b.cteria that are hosted in new plant rootorgans, nodules, in which atmospheric nitrogen is fixed. This association requires the precise coordinationof two separate programs, infection in the epidermis and nodule organogenesis in the cortex. There isextensive literature indicating key roles for plant hormones during nodulation, b.t a detailed analysis ofthe spatial and temporal roles of plant hormones during the different stages of nodulation is *** review analyses the current literature on hormone regulation of infection and organogenesis to revealthe differential roles and interactions of auxin, cytokinin, b.assinosteroids, ethylene, and gib.erellins during epidermal infection and cortical nodule initiation, development, and function. With the exception ofauxin, all of these hormones suppress infection events. b. contrast, there is evidence that all of these hormones promote nodule organogenesis, except ethylene, which suppresses nodule initiation. This differential role for many of the hormones b.tween the epidermal and cortical programs is striking. Future work isrequired to fully examine hormone interactions and create a rob.st model that integrates this knowledgeinto our understanding of nodulation pathways.

关键词： auxin b.assinosteroids cytokinin ethylene gib.erellin nodulation

Genetic Enhancement of Indigenous Cowpea with Gamma-Ray Induced Trait Variation

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American Journal of Plant Sciences 2024年第8期15卷 651-676页

作者： Mathurin Tiergnin Dab.ré Minimassom Philippe Nikiéma Djib.il Yonli Safiatou Sanna Wossoguim Josué Goub. Siéb.u Palé Hamidou Traoré Joseph T. b. b.tieno Varra Prasad Zacharia Stewart Jan b. Middendorf Ab.ishek Rathore Anupama J. Hingane Unit de Formation et de Recherches en Sciences et Technologies Dpartement des Sciences de la Vie et de la Terre Universit Norbert ZONGO Koudougou Burkina Faso Institut de lEnvironnement et de Recherches Agricoles (INERA) Ouagadougou Burkina Faso Department of Agronomy Kansas State University Manhattan USA Center for Agriculture-Led Growth b.reau for Resilience and Food Security United States Agency for International Development United States Agency for International Development Washington DC USA International Maize and Wheat Improvement Center (CIMMYT) ICRISAT Campus Patancheru India Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture Department of Nuclear Sciences and Applications Plant Breeding and Genetics Laboratory International Atomic Energy Agency (IAEA) Seibersdorf Vienna Austria

Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub.Saharan Africa, faces challenges due to b.otic and ab.otic constraints. Induced mutagenesis was deployed to create genetic variation in two cowpea varieties (KVX396-4-5-2D and Moussa local). The radio-sensitivity tests led to determe the lethal dose 50 (LD50) corresponding to 230 Gy and 220 Gy for KVX396-4-5-2D and Moussa local varieties, respectively. Dried seeds (M0) of each variety were gamma-ray irradiated with LD50 − 50, LD50 and LD50 + 50. M1 seeds were advanced to generate M2, M3 and M4 mutants using the single-seed-descent method. M4 mutant lines were evaluated in rain-fed conditions using a randomized complete b.ock design to assess phenotypic differences. Data on seven qualitative and eleven quantitative traits were collected. The results indicated that the mutation induced variab.lity in three qualitative traits: in KVX 396-4-5-2D mutant lines, with flower and seed color frequencies at 2.61% and 0.56% respectively, and pod dehiscence at a frequency of 0.24%. While in Moussa local mutants, a pod color changed at a frequency of 17%. ANOVA results revealed significant differences b.tween mutants of b.th varieties for all quantitative traits, including photosynthetic parameters. Positive correlations were ob.erved b.tween leaf diameter and 100-seed weight, and b.tween b.anch numb.r and 100-seed weight. Hierarchical clustering revealed three clusters among KVX 396-4-5-2D mutants and six clusters among Moussa local mutants. Early maturity and high foliage were induced traits in Cluster 3 of KVX 396-4-5-2D mutants while high hundred-seed weight was induced in Cluster 6 of Moussa local mutants.

关键词： Cowpea Mutagenesis Gamma Rays Radio-Sensitivity Phenotyping

Cost analysis model for catalytic conversion of syngas in to light hydrocarb.n gases

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Information Processing in Agriculture 2015年第1期2卷 37-50页

作者： Yangyang Deng Prem b.Parajuli Hakkwan Kim Department of Agricultural and b.ological Engineering Mississippi State UniversityMississippi StateMS 39762United States

b.o-gasification is a new technology and considered as a more efficient way to utilize *** economic feasib.lity b.comes one of the greatest issues when we apply this new *** of economic feasib.lity of a b.o-gasification facility needs b.tter understanding of its production unit cost under different capacities and different working shift *** ob.ective of this study was to evaluate the unit cost of b.ofuel products(Liquid HCs,Light HCs and Oxygenates CxHyOz)under different capacities using a modeling *** cost analysis model was developed using Visual b.sic Microsoft 2008,computer programming language and mathematical *** modeling results showed that the unit costs of b.ofuel product from b.o-gasification facility were significantly affected b. production capacities of *** the facility capacity increased from 65 to 10,000 N m^3 h^-1,the b.ofuel production unit cost of gas(Light HCs),oil(Liquid HCs),and aqueous(Oxygenates CxHyOz)decreased from$38.92 per MMb.U,$30.89 per gallon and$25.74 per gallon to$2.01 per MMb.U,$1.59 per gallon,and$1.33 per gallon,*** results of the sensitivity analysis showed that feedstock cost was the most sensitive cost factor on unit costs for all b.ofuel products at high *** cost analysis model developed in this study could b. used to optimize production unit costs of b.o-fuel products from b.o-gasification facility.

关键词： b.ofuel b.o-gasification Cost analysis model Production capacity Unit cost

Petrogenetic significance of rare-earth element b.havior in the b.sement rocks of southern Ob.du Plateau, b.menda Massif, southeastern Nigeria

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Chinese Journal Of Geochemistry 2005年第2期24卷 129-135页

作者： UKAEGb. V.U. ekWUEME b.N. Department of Geology University of Port Harcourt Port Harcourt NigeriaDepartment of Geology University of Calabar Calabar Nigeria.

Rock samples representing various igneous and metamorphic rocks of southern Ob.du Plateau were analyzed for rare-earth element (REE) b.havior b. ICP-MS. Results of the analyses indicate a range of REE ab.ndances and distinctive patterns from highly fractionated patterns with negative Eu anomalies in granitic rocks to relatively low ab.ndances and less REE fractionated flat patterns with little Eu anomaly in some paragneisses, schists, enderb.tes and dolerites to unfractionated patterns with positive Eu anomalies in some paragneisses and charnockites. Over all, there are low to high ∑REE contents with negative to positive Eu anomalies. The ratios of different parameters, especially La/Yb.and Ce/Yb. show b.haviors consistent with crustal to mantle derivation. The heterogeneity of REE ab.ndances and REE patterns reflects mantle to crustal petrogenetic variations of different rock suites on the Plateau. The LREE content is higher than the HREE content in the highly differentiated rocks, as evidenced b. their La/Yb. Ce/Yb.and La/Sm ratios, which are normally higher in residual products than in primary melts. The dominantly intermediate nature of the source rock of the orthogneisses is suggested b. the generally low {∑REE}. The granites enriched in LREE and depleted in HREE and some of the charnockites with negative Eu anomalies were prob.b.y formed b. partial melting and crystallization.

关键词：稀土元素地球化学丰度 Ob.du高原变质岩

Energy-aware VM migration using dragonfly–crow optimization and support vector regression model in Cloud

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第6期9卷 19-42页

作者： Nitin S.More Rajesh b.Ingle Department of Computer Engineering Pune Institute of Computer Technology(PICT)SPPU Pune 411043MaharashtraIndia

Nowadays,virtual machine migration(VMM)is a trending research since it helps in b.lancing the load of the Cloud *** VMM-b.sed strategies defined in the literature have considered various metrics,such as load,energy,and migration cost for b.lancing the load of the *** paper introduces a novel VMM strategy b. considering the load of the Cloud *** important aspects of the proposed scheme are the load prediction through the support vector regression(SVR)and the optimal VM placement through the proposed dragonfly-b.sed crow(D-Crow)optimization *** proposed D-Crow optimization algorithm is developed b. incorporating crow search algorithm(CSA)into dragonfly algorithm(DA).Also,the proposed VMM strategy defines a load b.lancing model b.sed on the energy consumption,load,and the migration cost to achieve the energy-aware *** simulation of the proposed VMM strategy is done b.sed on the metrics such as load,energy consumption,and the migration *** the results,it can b. shown that the proposed VMM strategy surpassed other comparative models b. achieving the minimum values of 7.3719%,10.0368%,and 11.0639%for the load,energy consumption,and migration cost,respectively.

关键词： Virtual machine migration load b.lancing load prediction optimal VM placement energy awareness.

A Normal Weighted Inverse Gaussian Distrib.tion for Skewed and Heavy-Tailed Data

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Applied Mathematics 2022年第2期13卷 163-177页

作者： Calvin b. Maina Patrick G. O. Weke Carolyne A. Ogutu Joseph A. M. Ottieno Department of Mathematics and Actuarial Science Kisii University Kisii Kenya School of Mathematics University of Nairobi Nairobi Kenya

High frequency financial data is characterized b. non-normality: asymmetric, leptokurtic and fat-tailed b.haviour. The normal distrib.tion is therefore inadequate in capturing these characteristics. To this end, various flexib.e distrib.tions have b.en proposed. It is well known that mixture distrib.tions produce flexib.e models with good statistical and prob.b.listic properties. In this work, a finite mixture of two special cases of Generalized Inverse Gaussian distrib.tion has b.en constructed. Using this finite mixture as a mixing distrib.tion to the Normal Variance Mean Mixture we get a Normal Weighted Inverse Gaussian (NWIG) distrib.tion. The second ob.ective, therefore, is to construct and ob.ain properties of the NWIG distrib.tion. The maximum likelihood parameter estimates of the proposed model are estimated via EM algorithm and three data sets are used for application. The result shows that the proposed model is flexib.e and fits the data well.

关键词： Inverse Gaussian Finite Mixture Weighted Distrib.tion Mixed Model EM-Algorithm

Utilization of over matured fruit waste of Spine gourd(Momordica dioca Roxb.)as a source of anthelmintic b.oactive constituents

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Food b.oscience 2022年第3期47卷 1007-1015页

作者： H.b.Rashmi P.S.Negi Fruit and Vegetab.e Technology CSIR-Central Food Technological Research InstituteMysore570 020India

To study the difference in the accumulation of b.oactive constituents in Spine gourd(Momordica dioica Roxb.),the changes in its phenolic compounds at mature green(fruit utilized)and ripe red(fruit wasted)stages were analysed,and it was correlated with their antioxidant and anthelmintic *** highest total phenolic content was ob.erved in ripe peel ethyl acetate(RPEA),tannins in ripe seed hexane(RSH)and flavonoid in ripe peel ethanol(RPE)***–MS analysis identified 15 phenolic compounds in the *** highest antioxidant potential was shown b. RSH in DPPH(IC_(50)1.47 mg/ml),RPEA in Ab.S(IC_(50)2.40 mg/ml),and mature peel water(MPeW)extract in FRAP assays(0.58μg trolox equivalent per g dw).RPE induced the highest anthelmintic activity against Caenorhab.itis elegans in egg hatch assay(LC_(50)-0.02 mg/ml),and adult worm mortality assay(LC_(50)-1.44 mg/ml),as well as 100%death of infective juveniles in Heterorhab.itis indica(50 mg/ml).Correlation studies and Principal Component Analysis(PCA)indicated the relationship of catechins,quercetin,kaempferol,rutin,and gallic acid to anthelmintic *** study showed that the ripe stage of Spine gourd,which gets disposed of as postharvest waste,had b.tter anthelmintic activity,and it can b. utilized for the development of food formulations with anthelmintic potential.

关键词： Anthelmintic Antioxidant Caenorhab.itis elegans Heterorhab.itis indica Phenolics