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Chinese Journal of Polymer Science 1989年第4期7卷 306-314页

作者：贾连达 F. r. SHEU r.T.CHErN H.B.HOPFENBErG Changchun Institute of Applide Chemistry Academia SinicaChangchunPRC Department of Chemical Engineering North Carolina State UniversityRaleighNC 27695USA

The apparent solubility (S), concentration-average diffusivity (D), and permeability (P), for C0_2, CH_4 and N_2 through PPO and aryl-brominated PPO at 35℃ for pressure ranging from 1 to 26 atm are reported. It is found that P, D, and S of the membranes to all the three gases vary with the extent of bromination. S increases with the increase of the percent of bromine in each case, but D to CO_2 increases remarkably only at higher degree of brominafion, and therefore, P to CO_2 is increased by more than 100% over a wide range ofpressure in the case. The solubility data are well described by the dual mode sorption model. It is found that the gas molecules sorbed by the Langmuir mode are relatively more immobilized and the contribution of the nonequilibrinm character of the polymer to gas permeation increases obviously for CO_2 and is hardly changed for CH_4 with increasing bromine content. These observations are interpreted in terms of changes in specific free volume (SFV)and the cohesive energy density (CED) of the polymers.

关键词： Poly (Phenylene Oxide) (PPO) Bromination Membrane Permeability.

Upward Molten Flow for Optimization of Fluid Flow in Continuous Casting Tundish

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Journal of Iron and Steel research International 2010年第11期17卷 29-33页

作者： A r Alaei H Edris E Shirani Department of Materials Engineering Isfahan University of Technology Department of Mechanical Engineering Isfahan University of Technology

Fluid flow pattern and buoyancy force support the motion of nonmetallic inclusions toward thetundish slag. Upward molten flow was investigated. To understand the fundamentals of the process, physical modelling was carried out with the utilization of a 1 ： 4 scale model. Numerical modelling was carried out in line with the physicai modelling to examine details of the flow pattern and rotational effect caused by the upward flow with the Commercial CFD （Computational Fluid Dynamics） package environment, FLUENT. The two-equation κ-ε model was used to simulate the turbulence. Multiphase fluid flow was numerically simulated by using the Volume of Fluid （VoF） method. The simulation can predict free surface waves and other phenomena, which can be used to optimize these important metallurgical operations.

关键词： upward flow continuous casting tundish numerical model water model

Process Dynamics and Fractal Analysis of New Phase Formation in Thermal Processes

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Journal of Thermal Science 2001年第2期10卷 153-158,115页

作者： wangJ ShenZ.w 等 DepartmentofChemicalEngineering DalianUniversityofTechnologyDalian116012China DepartmentofMathemati

Boiling and fouling are taken as typical examples of new phase formation process to be analyzed and discussed in this paper. The process dynamics of nucleate boiling is analyzed and its mechanism is discussed from the view point of self-organization. Fouling, which is a more complicated phenomenon of new phase formation, involves series of underlying processes. The morphology and fractal analysis of fouling on low-energy surface and that with fouling inhibitors are studied and discussed. It is suggested that considering the process dynamics, fractal analysis and self-organization, a new avenue of research should be found.

关键词： new phase formation process dynamics fractal analysis self-organization thermal process

THE COUPLED FEM ANALYSIS OF THE TrANSIENT TEMPErATUrE FIELD DUrING INErTIA FrICTION wELDING OF GH4169 ALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 301-306页

作者： L.w. Zhang J.B. Pei Q.Z. Zhang C.D. Liu w.H. Zhu S. Qu J.H. wang The State Key Laboratory for Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116023 China School of Materials Science and Engineering Dalian University of Technology Dalian 116023 China Shenyang Li Ming Aero-Engine Group Corporation Shenyang 110043 China

The inertia friction welding process is a non-linear process because of the interaction between the temperature field and the material properties as well as the friction force. A thermo-mechanical coupled finite element model is established to simulate the temperature field of this process. The transient temperature distribution during the inertia friction welding process of two similar workpieces of GH4169 alloy is calculated. The region of the circular cross-section of the workpiece is divided into a number of four-nodded isoparametric elements. In this model, the temperature dependent thermal properties, time dependent heat inputs, contact condition of welding interface, and deformation of the flash were considered. At the same time, the convection and radiation heat losses at the surface of the workpieces were also considered. A temperature data acquisition system was developed. The temperature at some position near the welding interface was measured using this system. The calculated temperature agrees well with the experimental data. The deformation of the flash and the factor affecting the temperature distribution at the welding interface are also discussed.

关键词： inertia friction welding temperature field numerical simulation finite element method

Is there evidence of selection in the dopamine receptor D4 gene in Australian invasive starling populations？

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Current Zoology 2015年第3期61卷 505-519页

作者： Lee Ann rOLLINS Michael r. wHITEHEAD Andrew r wOOLNOUGH ron SINCLAIr william B. SHErwIN Evolution & Ecology research Centre Biological Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia Centre for Integrative Ecology Life and Environmental Sciences Deakin University Locked Bag 20000 Geelong Victoria 3220 Australia Biosecurity Division Department of Economic Development Jobs Transport and Resources 1 Spring Street Melbourne Vic- toria 3000 Australia Vertebrate Pest research Section Department of Agriculture and Food 100 Bougainvillea Avenue Western Australia 6058 Australia Biosecurity SA GPO Box 1671 Adelaide South Australia 5001 Australia Murdoch University Cetacean research Unit Murdoch University South Road Murdoch Western Australia 6150 Australia Current address: Evolution Ecology and Genetics Research School of Biology The Australian National University Canberra Australia

Although population genetic theory is largely based on the premise that loci under study are selectively neutral, it has been acknowledged that the study of DNA sequence data under the influence of selection can be useful. In some circumstances, these loci show increased population differentiation and gene diversity. Highly polymorphic loci may be especially useful when studying populations having low levels of diversity overall, such as is often the case with threatened or newly established inva- sive populations. Using common starlings Sturnus vulgaris sampled from invasive Australian populations, we investigated se- quence data of the dopamine receptor D4 gene （DrD4）, a locus suspected to be under selection for novelty-seeking behaviour in a range of taxa including humans and passerine birds. we hypothesised that such behaviour may be advantageous when species encounter novel environments, such as during invasion. In addition to analyses to detect the presence of selection, we also esti- mated population differentiation and gene diversity using DrD4 data and compared these estimates to those from microsatellite and mitochondrial DNA sequence data, using the same individuals. we found little evidence for selection on DrD4 in starlings. However, we did find elevated levels of within-population gene diversity when compared to microsatellites and mitochondrial DNA sequence, as well as a greater degree of population differentiation. we suggest that sequence data from putatively non- neutral loci are a useful addition to studies of invasive populations, where low genetic variability is expected

关键词： DrD4 Starling Selection Novelty-seeking behaviour

Impact of fertility versus mortality control on the demographics of Mastomys natalensis in maize fields

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Integrative Zoology 2022年第6期17卷 1028-1040页

作者： Christopher I.IMAKANDO GMandela FErNÁNDEZ-GrANDON Grant r.SINGLETON Steven r.BELMAIN Natural resources Institute University of GreenwichChatham MaritimeKentUK Department of Zoology and Aquatic Sciences Copperbelt UniversityKitweZambia

The multimammate mouse,Mastomys natalensis,is the most common rodent pest species in sub-Saharan ***,rodenticides are the preferred method used to reduce the population of rodent pests,but this method poses direct and indirect risks to humans and other non-target *** control is a promising alternative that has been argued to be a more sustainable and humane method for controlling rodent *** this study,we compared the effectiveness of fertility control bait EP-1(quinestrol(E)and levonorgestrel(P),10 ppm)and an anticoagulant rodenticide bait(bromadiolone,50 ppm)on the population dynamics of *** in maizeﬁelds in Zambia during 2 cropping *** was the most abundant species in maizeﬁelds(77%of total captures).Fertility control reduced the number of juveniles and suppressed population growth of *** at the end of the 2019–2020 cropping *** population density initially decreased after rodenticide treatment,but the population rapidly recovered through *** of the treatments inﬂuenced maize damage by rodents at germination(F2,67=1.626,P=0.204).Applying the treatments during the maize seeding time was effective at suppressing population growth at the end of the cropping season than application the month before maize *** research indicates that a single-dose delivery of EP-1 and rodenticide have comparable effects on the population dynamics of ***ﬁndings are important in developing fertility control protocols for rodent pest populations to reduce maize crop damage and improve yields.

关键词： ecologically based rodent management levonorgestrel multimammate mouse quinestrol rodent pests rodenticide

Zero-Absorption Isolines in a 2-Photon 2-Level Atom Model

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Communications in Theoretical Physics 2017年第7期67卷 83-90页

作者： S.S.Hassan r.A.Alharbey King Abdulaziz University Faculty of Science Mathematics Department P.O. Box 42696 Jeddah 21551 Kingdom of Saudi Arabia

The c-number atomic Bloch equations modelling the coupling of a 2-photon 2-1evel single atom with a non-resonant （A # O） squeezed vacuum （SV） radiation reservoir show that：（i） The quantum interference （QI） process, of parameter f O, between the 2-photon transition channels causes coupling of the atomic variables （inversion and polarisation）, and, （ii） The SV reservoir parameters （N, M） induce periodic coefficients and hence inhibited oscillatory behaviour in the atomic variables. Perturbative analytical solutions of these non-autonomous B1och equations are derived and used to calculate the absorption spectrum of a weak field probing the system. Of particular, the zero-absorption isolines in the relevant （N, f）- and （A, f ）-planes of the the largest set of points, where absorption is zero, in parameter （M） of the SV reservoir. system parameters are identified computationally. It is found that, the （A, f）-plane depends on the choice of the degree of squeezing

关键词： non-autonomous Bloch equations 2-photon transition quantum interference squeezed vacuumreservoir absorption spectrum

EXPErIMENTAL STUDY ON INSTANTANEOUS DISCHArGE OF UNSOrTED PArTICLE CLOUD IN CrOSS-FLOw

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Journal of Hydrodynamics 2008年第1期20卷 10-16页

作者： GU Jie HUANG Jing LIC. w. College of Marine Science and Technology Shanghai Fisheries University Shanghai 200090 China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China

A series of extensive laboratory experiments were conducted to investigate the transport and mixing of instantaneous discharge of unsorted particle cloud in cross-flow. The following experimental results were obtained：（1） the vertical frontal position and the longitudinal width of the particle cloud in the cross-flow is much larger than those in stagnant water, （2） the smaller cross-flow velocity will normally cause the larger non-dimensional frontal position for the same particle size range and initial volume, （3） the non-dimensional longitudinal width of the particle cloud in the cross-flow increases with the increase of cross-flow velocity. The empirical constants （α1, α3 and α2） and their variance range, which can be used to determine the relationships of non-dimensional vertical frontal position and time, longitudinal width and time, and vertical frontal position and longitudinal width were also obtained through the analysis of experimental data.

关键词： instantaneous discharge particle cloud cross-flow buoyancy hydrodynamic behavior

Effects of multiple intravitreal anti-VEGF injections on retinal nerve fiber layer and intraocular pressure: a comparative clinical study

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 211-215页

作者： Güngr Sobaci riza Güngr Gkhan zge Department of Ophthalmology GATA Medical School Ankara

AIM: To determine the effect of multiple injections of ranibizumab or bevacizumab on retinal nerve fiber layer (rNFL) and intraocular pressure (IOP) in patients with age-related macular degeneration (AMD). ·METHODS: This retrospective study includes 35 eyes of 35 patients treated with intravitreal bevacizumab (IVB, 1.25mg/0.05mL) and 30 eyes of 30 patients with intravitreal ranibizumab (IVr, 0.5mg/0.05mL) who had Fast rNFL analysis (Stratus TM ); IOP measurements were taken 30 minutes and 24 hours after each injection. rESULTS: The mean ages were 68.0±7.5 and 69.1±7.7 years in the IVr and IVB groups, respectively (P =0.55). They underwent (6.3±1.9) and (5.1±1.3) injections (P = 0.07) over (13.6±2.1) and (14.05±2.6) months (P =0.45) in the IVr and IVB groups, respectively. Changes in overall and temporal rNFL thickness in IVr-treated eyes (105.3± 6.9μm and 74.4±11.2μm) were not different from those in untreated eyes in the IVr group (104.6±8.4μm and 75.1±12.6μm) (P =0.57 and P =0.41, respectively). Similarly, overall and temporal rNFL thickness in IVB-treated eyes (105.8±8.1μm and 74.5±11.8μm) were not different from those in untreated eyes in the IVB group (104.6±8μm and 74.8±12.9μm) (P=0.42 and P=0.80, respectively). The frequencies of IOP rise (P=0.60) and changes in rNFL thickness from baseline (P =0.16) were comparable between groups. CONCLUSION: repeated intravitreal injection of ranibizumab or bevacizumab does not seem have adverse effects on rNFL thickness or IOP in wet AMD patients.

关键词： anti-VEGF bevacizumab ranibizumab retinal nerve fiber layer intraocular pressure adverse effect