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Journal of Forestry Research 2018年第5期29卷 1241-1249页

作者： S.c.Das M.S.Alam M.A.Hossain Institute of Forestry and Environmental Sciences University of Chittagong

Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan（Dipterocarpus spp.）*** present study assessed composition,structure and diversity of the species in this protected area.A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 *** forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance *** turbinatus was the most dominant species with maximum relative density,frequency,dominance,and importance value *** firmum and Tectona grandis followed in terms of *** structural composition indicated higher number of individuals in the medium growth classes（41 to 〈 511 cm DBH and 16–20 m height ranges）,whereas *** was the only species that dominated most of the growth *** stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation,increased grazing and *** study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of *** will also contribute to identifying threatened plants to undertake *** based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary.

关键词： Species diversity Structural composition Protected area Importance value index cluster analysis

The effect of milling additives on powder properties and sintered body microstructure of Nio

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Journal of Advanced ceramics 2015年第2期4卷 142-151页

作者： L.Jay DEINER Michael A.RoTTMAyER Bryan c.EIGENBRoDT Department of chemistry New York City College of TechnologyCity University of New York300 Jay St.BrooklynNY 11201USA The Air Force Research Labs Wright-Patterson Air Force BaseOH 45433USA Department of chemistry Villanova University800 E.Lancaster Ave.VillanovaPA 19085USA

The evolution of powder particle size,crystal structure,and surface chemistry was evaluated for micron scale Nio powders subjected to impact milling with commonly employed milling additives:methanol,Vertrel XF,and amorphous *** effect of the different comminution protocols on sintered body microstructure was evaluated for high temperature sintering in inert atmosphere(N_(2)).X-ray photoelectron spectroscopy showed that Nio powder surface chemistry is surprisingly sensitive to milling additive *** particular,the proportion of powder surface defect sites varied with additive,and methanol left an alcohol or alkoxy residue even after *** sintering to intermediate temperatures(1100℃),scanning electron microscopy(SEM)showed that slurry milled Nio powders exhibit hindered sintering *** effect was amplified for Nio milled with methanol,in which sub-500 nm grain sizes dominated even after sintering to 1100℃.Upon heating to high temperatures(1500℃),simultaneous differential scanning calorimetry/thermogravimetric analysis(DSc/TGA)showed that the powders containing carbon residues undergo carbothermal reduction,resulting in a melting transition between 1425 and 1454℃.Taken together,the results demonstrated that when processing metal oxide powders for advanced ceramics,the choice of milling additive is crucial as it exerts significant control over sintered body microstructure.

关键词： nickel oxide impact milling sintering densification grain growth

optimization of cNc cutting parameters using design of experiment(DoE) and desirability function

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Journal of Forestry Research 2018年第5期29卷 1423-1434页

作者： Ender Hazir Emine Seda Erdinler Kücük Hüseyin Koc Department of Forest Industrial Engineering Faculty of ForestryIstanbul University

In this study,2~5 （five factors at two-level factorial design） design of experiment was applied to investigate a set of optimal machining parameters to achieve a minimum surface roughness value for Abies *** specimens were prepared using different values of spindle speed,feed rate,depth of cut,tool radius,and cutting *** surface roughness （R_z） values were applied using a *** objectives were to：（1）obtain the effective variables of wood surface roughness;（2） analyze which of these factors had an impact on variability in the cNc machining process;（3） evaluate the optimal cutting values within the range of different cutting levels of machining *** results indicate that the design of experiment（DoE） based on the desirability function approach determined the optimal machining parameters successfully,leading to minimum R_a compared to the observed *** surface roughness values of tangential and radial cutting directions were 3.58 and 3.21 μm,respectively.

关键词： Wood surface roughness optimization cNc Desirability function Pareto analysis

Influence of Zn Doping on Novel cathode Material LiFePo_4

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复旦学报（自然科学版） 2005年第5期44卷 877-878页

作者： H. Liu c. Li Q. cao H.P. Zhang y.P. Wu H.Q. Wu Department of chemistry ＆ Shanghai Key Laboratory of Molecular catalysis and Innovative Materials Fudan University Shanghai 200433 China

The novel cathode material LiFePo4 for lithium ion battery is considered as the substitute of Licoo2 because of its high theoretical capacity, environmental benignancy and inexpensive cost[1,2]. But it is restricted by its low conductivity, the traditional ways to improve are carbon coating[3,4] and heteroatom doping[5-7].In this paper, we introduced the Zn as heteroatom and investigated the improvement by Zn doping.

关键词： LiFePo4 锂电池电解液阴极电化学

Numerical Investigation of Penetration Performance of Non-Ideal Segmented-Rod Projectiles

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Transactions of Tianjin University 2008年第6期14卷 391-395页

作者： ALy S y School of Mechanical Aerospace and Civil EngineeringThe University of Manchester

The design of a segmented-rod projectile is often simplified into an ideal one in theoreti-cal analysis for the convenience of modeling of its *** the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely *** numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities,which can be used to guide the optimal design of weaponry segmented-rod projectiles.

关键词： penetration segmented-rod projectile numerical simulation

Effect of multi-walled carbon nanotube addition on the microstructures and mechanical properties of Ti(c,N)-based cermets

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Journal of Advanced ceramics 2018年第1期7卷 58-63页

作者： P.WU S.c.LIU X.R.JIANG college of chemistry and Materials Science Longyan University

The surface modification of multi-walled carbon nanotubes(MWcNTs) was carried out using plasma treatment. The microstructures of the prepared cermets with different additions of MWcNTs were investigated by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive X-ray analysis(EDX), and X-ray diffraction(XRD). Mechanical properties such as transverse rupture strength(TRS), fracture toughness(K_(Ic)), and hardness(HRA) were measured. The results showed that some reactive groups were successfully modified on the surface of MWcNTs, resulting in the improvement of dispersibility. Most of the amorphous carbons and impurities were peeled from the MWcNTs. Increasing MWcNT addition decreased the dissolution of tungsten, titanium, and molybdenum in the binder phase. The cermet with 0.5 wt% MWcNT addition showed the highest TRS and fracture toughness. The strengthening mechanisms were attributed to the finer grain size, the homogeneous microstructure, and the higher volume fraction of binder phase in the binder. The toughening mechanisms were characterized by bridging and pulling-out.

关键词： Ti(c,N)-based cermets microstructure mechanical property fracture toughness

Kinematics of whip spider pedipalps: a 3D comparative morpho-functional approach

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Integrative Zoology 2022年第1期17卷 156-167页

作者： Michel ScHMIDT Roland R.MELZER Russell D.c.BIcKNELL Bavarian State collection of Zoology Bavarian Natural History CollectionsMunichGermany Department Biology II Ludwig-Maximilians-Universität MünchenMunichGermany GeoBio-center Ludwig-Maximilians-Universität MünchenMunichGermany Palaeoscience Research centre School of Environmental and Rural ScienceUniversity of New EnglandArmidaleAustralia

Amblypygi are tropical and subtropical ambush predators that use elongated,raptorial pedipalps for different *** pedipalp use in predation and courtship has been explored in videography in vivo analyses,kinematic ex vivo examination of these appendages has not been ***,we rectify this lack of data by using microcT scans to 3D-kinematically model the appendage morphology and the range of motion(RoM)of the joints for Damon medius and Heterophrynus *** illustrate the successful application of this technique to terrestrial euarthropods in determining the maximum RoM values for each pedipalp *** also note that,in life,these values would be lower due to motion restricting structures like tendons,arthrodial membranes,and *** further compare our maximum values obtained here with data from video-based motion *** RoM of each joint shows the greatest flexibility in the femur-tibia joint(140–150°),the lowest in the basitarsus-claw joint(35–40°).RoM in the tibia-basitarsus joint is markedly distinct(***:44°;***:105°).This disparity reflects how *** uses the joint in the capture basket,while *** uses the femur-tibia joint to form the capture *** further illustrate notable vertical motion of the *** pedipalp compared to *** difference reflects the retro-ventral trochanter apophysis of *** study opens the possibility to further whip spider kinematic *** of other taxa using this approach will result in a more comprehensive understanding of the ecological significance and ethological implications of this unique arachnid group.

关键词： 3D kinematic analyses Amblypygi arthropod joints Autodesk Maya Damon medius Heterophrynus elaphus range of motion analyses

characterization and Photoluminescence Properties of Alumina Nanowires Elaborated by Arc-Plasma

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Journal of Materials Science & Technology 2006年第1期22卷 127-129页

作者： c.Arnoult X.Devaux H.Rinnert M.Vergnat Laboratoire de Physique des Materiaux UMR CNRS 7556Ecole des MinesCS14234F54042 Nancy cedexPrance

Ultrafine powders containing alumina nanowires are synthesized by Dc arc plasma from pure aluminium metal. Nanowires grow only when reactive gases are composed of nitrogen and less than ten percent of oxygen. Nanowires have the diameters ranging from 20 to 80 nm and lengths ranging from hundreds nanometers to tens of micrometers. A first assumption of the mechanism process is proposed, in which nanowires grow starting directly from the aluminium. Photoluminescence measurements show that the powders have three emission peaks around 435, 530 and 750 nm resulting from different kinds of defects such as oxygen vacancies, aluminium interstitial ions and surface defects.

关键词： Nanowires Alumina Arc plasma Photoluminescence

Electrochemical response of Nd3+ ions containing lithium borate glasses

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Journal of Rare Earths 2017年第5期35卷 480-484页

作者： D.D.Ramteke H.c.Swart R.S.Gedam Department of Physics University of the Free State Department of Applied Physics Visvesvaraya National Institute of Technology

The present investigation was to understand the electrical properties of 27.5 Li2o-(72.5–x) B2o3-xNd2o3with x=0.5, 1, 1.5 and 2 glasses. We analyzed the impedance data for a wide frequency range to get inside the conduction phenomenon. The conductivity of the glasses decreased due to the decrease in the mobility of mobile Li+ions. This decrease was due to polymerization of glass network caused by the Nd3+ions. Modulus formalism confirmed that the Li+ions overcame the same barrier no matter whether it took part in the conduction process or relaxation process. Scaling of the electrochemical data showed that conduction process in the ion conducting glasses was composition dependent and not the temperature dependent.

关键词： glasses impedance spectroscopy electrical properties modulus formalism scaling rare earths

Transcatheter aortic valve replacement and stroke： a comprehensive review

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Journal of Geriatric cardiology 2018年第1期15卷 95-104页

作者： Periklis A Davlouros Virginia c Mplani Ioanna Koniari Grigorios Tsigkas George Hahalis Department of cardiology Patras University Hospital Rion Patras Greece

Transcatheter aortic valve implantation （TAVR） has emerged as an alternative, rapidly evolving treatment option for patients with se- vere aortic stenosis and high surgical risk. Stroke is a devastating complication being confined mainly in the periprocedural and 30-day pe- riod following TAVR, with a lower and relatively constant frequency thereafter. Early stroke is mainly due to debris embolization during the procedure, whereas later events are associated with patient specific factors. Despite the fact that the rate of clinical stroke has been constantly decreasing compared to initial TAVR experience, modern neuro-imaging with MRI suggests that new ischemic lesions post-TAVR are almost universal. The impact of the latter is largely unknown. However, they seem to correlate with a reduction in neurocognitive function. Because TAVR is set to expand its indication to lower surgical-risk patients, stroke prophylaxis during and after TAVR becomes of paramount importance. Based on clinical and pathophysiological evidence, three lines of research are actively employed towards this direction： improvement in valve and delivery system technology with an aim to reduce manipulations and contact with the calcified aortic arch and native valve, antithrombotic therapy, and embolic protection devices. careful patient selection, design of the procedure, and tailored antithrombotic strategies respecting the bleeding risks of this fragile population constitute the main defense against stroke following TAVR.

关键词： Aortic stenosis Stroke Transcatheter aortic valve replacement