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Recovery of threatened plant species and their habitats in the biodiversity hotspot of the Southwest Australian Floristic Region

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Plant Diversity 2019年第2期41卷 59-74页

作者： Leonie Monks Sarah barrett brett beecham Margaret byrne Alanna Chant David Coates j.Anne Cochrane Andrew crawford Rebecca Dillon Colin Yates biodiversity and Conservation Science Department of Biodiversity Conservation and Attractions Parks and Wildlife Service Department of Biodiversity Conservation and Attractions

The Southwest Australian Floristic Region(SWAFR) is a global biodiversity hotspot with high plant diversity and endemism and a broad range of threatening processes. An outcome of this is a high proportion of rare and threatened plant species. Ongoing discovery and taxonomic description of new species, many of which are rare, increases the challenges for recovery of threatened species and prioritisation of conservation actions. Current conservation of this diverse flora is based on integrated and scientific evidence-based management. Here we present an overview of current approaches to the conservation of threatened flora in the SWAFR with a focus on active management through recovery and restoration that is integrated with targeted research. Key threats include disease, fragmentation, invasive weeds, altered fire regimes, grazing, altered hydro-ecology and climate change. We highlight the integrated approach to management of threats and recovery of species with four case studies of threatened flora recovery projects that illustrate the breadth of interventions ranging from In situ management to conservation reintroductions and restoration of threatened species habitats. Our review and case studies emphasise that despite the scale of the challenge, a scientific understanding of threats and their impacts enables effective conservation actions to arrest decline and enhance recovery of threatened species and habitats.

关键词： Threatened species Threatening processes Conservation Recovery Restoration biodiversity hotspot

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Field investigation on effects of railway track geometric parameters on rail wear

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1846-1855页

作者： SADEGHI j. AKbARI b. School of Railway Engineering Iran University of Science and Technology Narmak Tehran Iran

Rail wear has dramatic impact on track performance, ride quality and maintenance costs. The amount of rail wear is influenced by various elements among which geometric parameters play an important role. The amount of wear in Iran’s railway lines and its imposed maintenance costs oblige us to make modifications on the various geometrical parameters. In order to ensure the effectiveness of these changes, it is necessary to investigate these parameters and their effects on the wear. This research is aimed at studying the effects of different track geometrical parameters on the vertical and lateral wear by conducting a three phase field investigation. The first phase was carried out at the switches of a station, the second phase at a straight line, and the third at a curved line out of the station. The results obtained are analyzed and the role of each track geometrical parameter in the rail wear is discussed. Recommendations for prevention or reduction of rail wear are presented.

关键词： Rail wear Vertical and lateral wear Superelevation Gauge Longitudinal slope Track geometry

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Luminescence properties of sol-gel derived silica gels doped and undoped with RE-complexes(RE=Eu,Tb)

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Chinese journal of Chemistry 1997年第4期15卷 327-335页

作者： Lin, j Li, b Zhang, Hj CHINESE ACAD SCI CHANGCHUN INST APPL CHEMRARE EARTH CHEM & PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The luminescence properties of silica gels and silica gels doped with two rare earth complexes, Eu(TTA)(3) and Tb(o-CbA)(3) (TTA=thenoyltriffuocetate, o-CbA=o-chlorobenzoic acid) are reported and discussed. Pure silica gels show a blue luminescence, and the maximum excitation and emission wavelengths depend strongly on the solvents used. both of the studied rare earth complexes exhibit the characteristic emissions of the rare earth ions in silica gels, i.e., Eu3+5D0-->F-7(j)(j=0,1,2,3,4), Tb3+5D4-->F-7(j)(j=3,4,5,6) transitions. Compared with the pure RE-complexes powder, the silica gels doped with RE-complexes show fewer emission lines of the rare earth ions. Furthermore the rare earth ion (Tb3+) presents a longer lifetime (1346 mu s) in silica gel doped with Tb(o-CbA)3 than in pure Tb((o-CbA)(3) powder (744 mu s). The reasons responsible for these results are discussed in the context.

关键词： sol-gel method luminescence silica gel rare earth complexes

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Consequence of exponential heat generation on non-Darcy- Forchheimer flow of water based carbon nanotubes driven by a curved stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2020年第11期41卷 1723-1734页

作者： b.j.GIREESHA b.NAGARAjA S.SINDHU G.SOWMYA Department of P.G.Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India

The present article comprises the study on the influence of exponential space based heat generation on the non-Darcy-Forchheimer flow of carbon nanotubes(CNTs).The flow is considered over a curved stretching *** variables are used to reduce the flow descriptive nonlinear partial derivative equations to simple *** equations are then solved by the exploiting Runge-Kutta-Fehlberg fourth-and fifth-order *** numerical solutions are shown in graphs and *** between single and multi-walled CNTs has been established through the tabulated values and plotted *** is concluded that the heat source parameter plays a prime role in enhancement of temperature,and the curvature parameter has adverse impact on velocity and temperature *** the inertial parameter and inverse-Darcy number affect the fluid velocity.

关键词： exponential heat generation non-Darcy-Forchheimer flow carbon nanotube(CNT) curved stretching sheet

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Identification of boundary surfaces in flows

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Applied Mathematics and Mechanics(English Edition) 2010年第9期31卷 1097-1104页

作者： b.HERRERA j.PALLARES Department d'Enginyeria Informàtica i Matematiques Universitat Rovira i VirgiliAvinguda Pasos Catalans 26Tarragona 43007Spain Department d'Enginyeria Mecànica Universitat Rovira i VirgiliAvinguda Pasos Catalans 26Tarragona 43007Spain

In this study, boundary surfaces of a flow field are defined as stream surfaces, on which the shear rates vanish, and a procedure is proposed to find them. The method, based on calculations using the velocity vector f... 详细信息

关键词： interracial surfaces structure of flow kinematics

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Exact solution of Schrdinger equation with q-deformed quantum potentials using Nikiforov–Uvarov method

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Chinese Physics b 2013年第11期22卷 166-173页

作者： Falaye b.j. Oyewumi K.j. Abbas M. Theoretical Physics Section Department of Physics University of Ilorin Physics Department Kebbi State University of Science and Technology

In this paper, we present the exact solution of the one-dimensional Schrrdinger equation for the q-deformed quantum potentials via the Nikiforov-Uvarov method. The eigenvalues and eigenfunctions of these potentials are obtained via this method. The energy equations and the corresponding wave functions for some special cases of these potentials are briefly discussed. The PT-symmetry and Hermiticity for these potentials are also discussed.

关键词： Schrōdinger equation q-deformed quantum potential Woods-Saxon potential Nikiforov-Uvarovmethod

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Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu S.j.Liu b.Wang W.b.Sun X.j.Liu Z.W.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

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Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： jason b. Miller Daniel j. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of biochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Ribonucleic acids （RNAs） possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanornaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

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A COMPARATIVE STUDY OF THE INVENTORY SYSTEM WITH SERVICE FACILITY AND POSTPONED DEMANDS

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journal of Systems Science and Systems Engineering 2014年第2期23卷 176-195页

作者： j.Sebastian Arockia jenifer b.Sivakumar School of Mathematics Madurai Kamaraj University

In this article, we present a continuous review （s,S） inventory system with a service facility consisting of finite buffer （capacity N ） and a single server. The customers arrive according to a Poisson process. The individual customer＇s unit demand is satisfied after a random time of service, which is assumed to be exponential. When the inventory level drops to s＇an order for Q（= S-s） items is placed. The lead time of reorder is assumed to be exponential distribution. An arriving customer, who finds the buffer is full, enters into the pool of infinite size or leaves the system according to a bernolli trial. At the time of service completion, if the buffer size drops to a preassigned level L （1 〈 L 〈 N） or below and the inventory level is above s, we select the customers from the pool according to two different policy ： in first policy, with probability p （0 〈 p 〈 1） we select the customer from the head of the pool and we place the customer at the end of the buffer; in the second policy, with p （0 〈 p 〈 1） the customer from the pool is transferred to the buffer for immediate service and after completion of his service we provide service to the customer who is in the buffer with probability one. If at a service completion epoch the buffer turns out to be empty, there is at least one customer in the pool and the inventory level is positive, then the one ahead of all waiting in the pool gets transferred to the buffer, and his service starts immediately. The joint probability distribution of the number of customers in the pool, number of customers in the buffer and the inventory level is obtained in the steady-state case. Various stationary system performance measures are computed and total expected cost rate is calculated. A comparative result of two models is illustrate numerically.

关键词： Continuous review inventory system postponed demands service facility finite waiting hall pool with infinite size

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Magnetically propelled Carreau fluid flow over penetrable sensor surface influenced by thermal radiation,joule heating and heat generation

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Communications in Theoretical Physics 2022年第2期74卷 9-18页

作者： b j Gireesha b Nagaraja N Srikantha N G Rudraswamy A Felicita Department of Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamoggaKarnatakaIndia Department of Mathematics MS Ramaiah Institute of TechnologyBangaloreIndia Department of Mathematics P.C.Jabin Science College(Autonomous)HubballiIndia

This examination emphasizes the analysis of thermal transmission of Carreau fluid flow on a permeable sensor surface equipped with radiation,joule heating,an internal heat source,and a magnetic *** the above effects and assumptions,the equations that administer the flow are formulated.A configured system of equations is productively reduced to a system of ordinary differential *** reduced system is then dealt with using the Runge–Kutta-Fehlberg fourth–fifth order tool equipped by the shooting *** numerical solutions are utilized to plot graphs and *** conclusion of the study outlines some important findings such as the power law index,the thermal radiation parameter and the heat source parameter enhance the thermal panel whereas the Weissenberg number deescalates the *** power law index and permeable velocity decrease the velocity panel *** representation of streamlines of the flow has been given to strengthen the study.A detailed description has been produced about the results obtained in the study.

关键词： sensor surface Carreau fluid squeezed flow thermal radiation heat generation

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