检索结果-南通市图书馆

Frontiers of Chemical Science and Engineering 2021年第3期15卷 552-561页

作者： Hongzhan Di Gregory j.o.Martin Dave E.Dunstan Department of Chemical and Biomolecular Engineering University of MelbourneParkvilleVictoria 3010Australia

Particle deposition during crossflow filtration is significantly influenced by the operating conditions,in particular the permeate flux and crossflow ***,there is a lack of detailed knowledge about how deposit layer structures and distributions depend on operating *** study uses a microfluidic visualisation filtration system to examine the influence of operating conditions on the deposition process during crossflow ultrafiltration from a microscopic *** the permeate flux caused an increasing amount of deposition and a thicker deposit *** crossflow velocities reduced the extent of *** degree of deposition varied over a range of operating conditions due to the altered hydrodynamic forces exerted on the particles,which can be examined by the deposition probability according to an existing *** on this,an empirical correlation between the deposition probability and volume of deposition as a function of filtration time was developed,which gave good agreement with experimental *** effect of solution conditions was also involved in this correlation as a interaction *** could be useful for predicting the dynamic deposition process during crossflow filtration over a range of operating and solution conditions.

关键词： particle deposition crossflow filtration microfluidics confocal microscopy

Electrochemical studies on interplay of mineralogical variation and particle size on bioleaching low grade complex sulphide ores

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第5期19卷 1312-1325页

作者： P.A.oLUBAMBI j.H.PoTGIETER S.NDLoVU j.o.BoRoDE Department of Chemical and Metallurgical Engineering Tshwane University of TechnologyPretoriaSouth Africa Chemistry and Materials Division School of BiologyChemistry and Health SciencesManchester Metropolitan UniversityUK School of Chemical and Metallurgical Engineering University of the WitwatersrandJohannesburgSouth Africa Department of Metallurgical and Materials Engineering Federal University of TechnologyAkureNigeria

The interplay of mineralogical variation and mineral phase distribution within varying particle sizes on the dissolution behaviour of a low grade complex sulphide ore was investigated through bioleaching experiments and electrochemical technique. Investigations were carried out utilizing mineralogical data on the variations in mineral and phase distribution within particle sizes of ophilic cultures of Acidithiobacillus ferrooxidans,Acidithiobacillus thiooxidans and Leptospirillum *** behaviour was studied using particulate electrodes from the four varying particle sizes and from massive electrodes prepared from the two major sulphide mineral rich phases(sphalerite-rich and galena-rich)and a complex mineralogical phase of the bulk *** studies reveal the highest recoveries at a particle size of 75μm,while electrochemical investigations reveal the highest dissolution at particle size of 106μ*** results show that sphalerite rich phase has the highest dissolution rate while galena-rich complex phase has the *** studies confirm the highest bacterial attack at the sphalerite-rich *** discrepancies between the dissolutions within particle sizes obtained from bioleaching experiments and electrochemical studies are consistent with and attributed both to the physical and mineralogical *** behaviour is influenced and controlled by galvanic interaction resulting from mineralogical variation, while bioleaching behaviour is influenced by mineralogical variation as well as physical effect of particle size.

关键词：复杂硫化矿化学研究颗粒大小低品位浸出用电互作矿物

Role of ore mineralogy in optimizing conditions for bioleaching low-grade complex sulphide ores

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2008年第5期18卷 1234-1246页

作者： P.A.oLUBAMBI S.NDLoVU j.H.PoTGIETER j.o.BoRoDE School of Chemical and Metallurgical Engineering University of the Witwatersrand Department of Metallurgical and Materials Engineering Federal University of Technology

The role that ore mineralogy plays in understanding and optimizing the conditions favouring the bioleaching of complex sulphide ore containing high amounts of siderite was studied using mixed cultures of mesophilic bacteria,with emphasis on zinc,lead and copper *** influencing parameters investigated include particle size,stirring speed,volume of inoculum,pulp density,and *** results show that the mixed mesophilic cultures can extract about two and a half times the amount of zinc than copper over an equivalent period of *** highest zinc and copper recoveries of 89.2% and 36.4% respectively are obtained at particle size of 75 μm,stirring speed of 150 r/min,pulp density of 10% (w/v),12% (v/v) inoculum concentration,and a pH of *** in elemental composition within different particle sizes resulting from the mineralogy of the ore account for the bioleaching behaviour at varying particle *** dissolution at varying pulp density,volume of inoculum,solution pH and the low solution potential observed are also influenced by ore mineralogy.

关键词：硫化物矿石矿石矿物学生物浸取加工参数

Ca^(2+)signaling in plant responses to abiotic stresses

在线全文

学校读者我要写书评

暂无评论

journal of Integrative Plant Biology 2022年第2期64卷 287-300页

作者： Qiuyan Dong Lukas Wallrad Bader o.Almutairi jörg Kudla Institute of Plant Biology and Biotechnology WWU MünsterSchlossplatz 7Münster48149 Germany Department of Zoology College of ScienceKing Saud UniversityRiyadhKingdom of Saudi Arabia

Adverse variations of abiotic environmental cues that deviate from an optimal range impose stresses to *** stresses severely impede plant physiology and ***,such stresses dramatically reduce crop yield and negatively impact on ecosystem stability and *** components of abiotic stresses can be,for example,suboptimal temperature and osmotic perturbations,while representative chemical facets of abiotic stresses can be toxic ions or suboptimal nutrient *** sheer complexity of abiotic stresses causes a multitude of diverse components and mechanisms for their sensing and signal ***^(2+),as a versatile second messenger,plays multifaceted roles in almost all abiotic stress responses in that,for a certain abiotic stress,Ca^(2+)is not only reciprocally connected with its perception,but also multifunctionally ensures subsequent signal ***,we will focus on salt/osmotic stress and responses to altered nutrient availability as model cases to detail novel insights into the identity of components that link stress perception to Ca^(2+)signal formation as well as on new insights into mechanisms of Ca^(2+)signal ***,we will deduce emerging conceptual consequences of these novel insights and outline arising avenues of future research on the role of Ca^(2+)signaling in abiotic stress responses in plants.

关键词： abiotic stress calcium signaling nutrient stress salt stress

Semi-Relativistic Reflection and Transmission Coefficients for Two Spinless Particles Separated by a Rectangular-Shaped Potential Barrier

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2016年第10期65卷 389-395页

作者： K.E.Thylwe o.j.oluwadare K.j.oyewumi KTH-Mechanics Royal institute of Technology Department of Physics Federal University Oye-Ekiti Theoretical Physics Section Department of PhysicsUniversity of Ilorin

A generalized Schr¨odinger approximation,due to Ikhdair & Sever,of the semi-relativistic two-body problem with a rectangular barrier in(1+1) dimensions is compared with exact *** and approximate transmission and reflection coefficients are obtained in terms of local wave *** approximate transmission and reflection coefficients turn out to be surprisingly accurate in an energy range |∈-V0| op *** approximate wave numbers are less accurate.

关键词： two-body relativistic equation rectangular barrier transmission 1+1D relativistic scattering semi-relativistic approximation spinless Salpeter equation

Non-Relativistic Phase Shifts for Scattering on Generalized Radial Yukawa Potentials

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2016年第4期65卷 434-440页

作者： o.j.oluwadare K.E.Thylwe K.j.oyewumi Department of Physics Federal University Oye-Ekiti KTH-Mechanics Royal institute of Technology Theoretical Physics Section Department of PhysicsUniversity of Ilorin

Non-relativistic phase shifts for a generalized Yukawa potential V(r) =-V_0( e^(-αr)/r)-V_1( e^(-2αr)/r^2) are studied by the amplitude-phase method and by a frequently used analytic method based on a Pekeris-type approximation of power-law potential *** variations of V_1 seem to have marginal effects on the effective potential and on exact phase ***,as pointed out in this study,a Pekeris-type approximation in scattering applications often implies serious distortions of both effective potentials and phase *** Pekeris-type based analytic approximation in this study seems to give low-quality scattering results for this model potential at low energies.

关键词： quantum mechanics scattering partial waves resonances

Mineral dust resuspension under vibration: onset conditions and the role of humidity

在线全文

学校读者我要写书评

暂无评论

Particuology 2020年第3期18卷 112-119页

作者： F.j.Balladore j.G.Benito R.o.Unac A.M.Vidales Departamento de Mineria Facultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisChacabuco 917D5700HHWSan LuisArgentina INFAP CONICETDepartamento de FisicaFacultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisEjercito de los Andes 950D5700HHWSan LuisArgentina

The vibration of dusty surfaces inevitably causes re-entrainment of particles into the *** that movement of mineral dust particles deposited on a surface begins at a critical frequency (fc) and amplitude,an experimental laboratory study was conducted to determine the onset conditions for resuspension of a vibrated granular *** determined the resuspension state diagram as a function of frequency and amplitude of a sinusoidal vibration,the granulometry of the dust and the thickness of the soil *** mitigation effect of humidity was also *** frequencies ranged between 2.5 and 23 Hz when amplitudes were less than 12 *** results were independent of bed thickness and perturbation *** all particle sizes observed,fc decreased monotonically with A,contrasting with behavior observed for individual *** dry samples,fe for large size classes was markedly less when A was greater than 6 mm;while thefc for fine fractions only decreased once amplitudes reached 10 *** with wet granular soils demonstrated that wetting above an optimum humidity did not necessarily impede movement and caused *** study provides guidelines for managing resuspension of granular soils subjected to vibrations.

关键词： Resuspension Vibration Granular soil Mineral dust Critical frequency Humidity

Role of ABCC2 common variants in intrahepatic cholestasis of pregnancy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World journal of Gastroenterology 2008年第13期14卷 2126-2127页

作者： Silvia Sookoian Gustavo Castao Carlos j Pirola Department of Molecular Genetics and Biology of Complex Diseases Institute of Medical Research A. Lanari University of Buenos Aires-CONICET Buenos Aires 1427 Argentina Research Council of GCBA Buenos Aires 1427 Argentina

The pathogenesis of intrahepatic cholestasis of pregnancy (ICP), a disorder that adversely affects maternal wellbeing and fetal outcome, is unclear. However, multiple factors probably interact along with a genetic predisposition. We would like to add some comments on a paper recently published concerning the role of ABCB11 and ABCC2 polymorphisms in both ICP and contraceptive-induced cholestasis, especially in the light of our recently published findings about a positive association between ICP and ABCC2 common variants.

关键词： Intrahepatic cholestasis of pregnancy ABCC2 MRP2 Gene variants

Vibrational resonance in a multistable system with position-dependent mass

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2023年第11期75卷 115-134页

作者： T o Roy-Layinde K A omoteso o T Kolebaje F o ogunmefun R A Fasasi j A Laoye U E Vincent Department of Physics Olabisi Onabanjo UniversityAgo-IwoyeOgun StateNigeria Department of Physics Adeyemi Federal University of EducationOndoNigeria Department of Physical Sciences Redeemer’s UniversityP.M.B.230EdeNigeria Department of Physics Lancaster UniversityLancaster LA14 YBUnited Kingdom

The occurrence of vibrational resonance(VR)in a dual-frequency-driven multistable system with a spatially varying mass modelling particle with position-dependent mass(PDM)and evolving in a one-dimensional symmetric periodic potential has been investigated and reported in this *** numerically compute and analyze the response amplitude,the effects of the PDM parameters(m0,a)on the potential structure,the occurrence of VR and the bifurcation of the equilibrium *** is shown that the PDM parameters,besides controlling VR,can induce unconventional resonance patterns through the variation of the potential well *** resonant states can be influenced through the cooperation of the PDM parameters and the external forcing leading the system from multiresonance state into single and double resonance *** contributions of the fixed rest mass m0 on the VR and the PDM-induced resonance are determined by threshold conditions imposed by the magnitude of the mass nonlinear strength a.

关键词： vibrations resonance position-dependent mass multistable oscillator dualfrequency force nonlinear systems

Tipping points among social learners： Tools from varied disciplines

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2012年第2期58卷 298-306页

作者： R. Alexander BENTLEY Michael j. o＇BRIEN Department of Archaeology and Anthropology University of Bristol Bristol BS8 1UU UK Department of Anthropology University of Missouri Columbia MO 65211 USA

There is a long and rich tradition in the social sciences of using models of collective behavior in animals as jump- ing-off points for the study of human behavior, including collective human behavior. Here, we come at the problem in a slightly different fashion. We ask whether models of collective human behavior have anything to offer those who study animal behavior. our brief example of tipping points, a model first developed in the physical sciences and later used in the social sciences, suggests that the analysis of human collective behavior does indeed have considerable to offer

关键词： Networks Social learning Thresholds Time series Tipping points