316,255 research outputs found
The Li intercalation potential of LiMPO 4 and LiMSiO 4 olivines with M = Fe, Mn, Co, Ni
No full textThe Li intercalation potential of LiMPO4 and LiMSiO4 compounds with M = Fe, Mn, Co and Ni is computed with the GGA + U method. It is found that this approach is considerably more accurate than standard LDA or GGA methods. The calculated potentials for LiFePO4, LiMnPO4 and LiCoPO4 agree to within 0.1 V with experimental results. The LiNiPO4 potential is predicted to be above 5 V. The potentials of the silicate materials are all found to be rather high, but LiFeSiO4 and LiCoSiO4 have negligible volume change upon Li extraction
Closure to “Discussion of \u27measurement of Stiffness Anisotropy in Kaolinite using Bender Element Tests in a Floating Wall Consolidometer\u27 by X. Kang, G.-C. Kang, and B. Bate” by Coffman, Salazar and Zhao
No full textThe authors appreciate the interest of the discussers in this paper. The main arguments of the discussers were: (1) comparing the back-pressure saturated, constant-rate-of-strain consolidation device that incorporated bender elements (BP-CRS-BE device) developed by the discussers to the floating wall consolidometer based bender element testing system in the original paper (Kang, X., Kang, G.-C., and Bate, B., 2014, Shear Wave Velocity Anisotropy of Kaolinite Using a Floating Wall Consolidometer-Type Bender Element Testing System, Geotech. Test. J., Vol. 37, No. 5, pp. 869-883. [DOI: 10.1520/GTJ20120205]); (2) requesting the quantification of both the system lag and the machine deflection; (3) suggesting the authors use cross correlation method to determine the first arrival time because Vs values obtained by time domain method are only approximate, while the latter was the only method used by the discussers in their referenced work (Salazar, S. E. and Coffman, R. A., 2014, Design and Fabrication of End Platens for Acquisition of Small-Strain Piezoelectric Measurements during Large-Strain Triaxial Extension and Triaxial Compression Testing, Geotech. Test. J., Vol. 43, No. 2. pp. 1-11. [DOI: 10.1520/GTJ20140057]); and (4) making misleading arguments regarding the compression and shear waves measurements. In this closure, the authors first briefly compared the BP-CRS-BE device to the floating wall consolidometer based bender element testing system, and pointed out that (1) the well-documented wavelength ratio (Rd ratio) consideration in designing a bender element device and the seemingly unsatisfaction of such consideration in the BP-CRS-BE device, and that (2) both the lack of details in B-value checking to examine saturation and the lack of shear wave velocity resulted from the BP-CRS-BE device to substantiate the arguments of the discussers. Then the authors provided the requested quantifications of both system lag and machine deflection to address some postulations by the discussers. The authors disagreed with Arguments 3 and 4 made by the discussers, and respond accordingly
Strategies and Practices for Suppressing Abnormal Grain Growth during Liquid Phase Sintering
No full textAbnormal grain growth (AGG), where a small number of grains grow to sizes much larger than the neighboring matrix grains, is a frequent occurrence in liquid phase sintering of ceramics and cermets. As AGG can be detrimental to the material properties, a considerable amount of research on the nature, causes and suppression of AGG has been carried out. In this review, we outline the mixed control theory of grain growth and the principle of microstructural evolution that have been developed by Kang and coworkers over the last two decades. The theory and the principle, which are based on theories of crystal growth from a liquid, state that grain growth behavior is controlled by the nature of the solid-liquid interfaces, either atomically rough (macroscopically rounded) or smooth (macroscopically faceted). For grains with atomically rough solid-liquid interfaces, growth is controlled by diffusion of solute through the liquid phase and normal grain growth always occurs. For grains with faceted solid-liquid interfaces (or a mixture of rough and faceted interfaces), growth is interface reaction-controlled and diffusion-controlled below and above a critical driving force for growth, respectively. Depending on the relative values of the critical driving force for growth Delta g(c) and the maximum driving force for the largest grain in the system Delta g(max), pseudo-normal, abnormal, and stagnant grain growth can take place. Based on this theory and principle, we present strategies for suppressing AGG by adjusting Delta g(c) and Delta g(max) to avoid AGG and examples of the successful use of these strategies
FIGURE 1. Eriobotrya shanense D.H. Kang, H.G. Ong & Y.D. Kim A. Flowering branch B. Leaf blade C–D. Stipules E. Bract F–G. Flower abaxial and adaxial view H–I. Petals J. Flower longitudinal section showing the androecium and gynoecium K. Stamen L. Styles and exposed ovary M. Ovary cross section N. Fruiting branch O–P. Fruit cross and longitudinal section. A–M in A new broad-leaved species of loquat from eastern Myanmar and its phylogenetic affinity in the genus Eriobotrya (Rosaceae)
No full textFIGURE 1. Eriobotrya shanense D.H. Kang, H.G. Ong & Y.D. Kim A. Flowering branch B. Leaf blade C–D. Stipules E. Bract F–G. Flower abaxial and adaxial view H–I. Petals J. Flower longitudinal section showing the androecium and gynoecium K. Stamen L. Styles and exposed ovary M. Ovary cross section N. Fruiting branch O–P. Fruit cross and longitudinal section. A–M. from Kim et al. MM-6026 (holotype HHU). Illustration by Ye-Seul Jang.Published as part of Kang, Dae-Hyun, Ong, Homervergel G., Lee, Jung-Hoon, Jung, Eui-Kwon, Kyaw, Naing-Oo, Fan, Qiang & Kim, Young-Dong, 2021, A new broad-leaved species of loquat from eastern Myanmar and its phylogenetic affinity in the genus Eriobotrya (Rosaceae), pp. 279-290 in Phytotaxa 482 (3) on page 283, DOI: 10.11646/phytotaxa.482.3.6, http://zenodo.org/record/478458
Millimeter-Wave UAV Coverage in Urban Environments
No full textComunicació presentada a 2021 IEEE Global Communications Conference (GLOBECOM), celebrat del 7 a l'11 de desembre de 2021 a Madrid, Espanya.With growing interest in mmWave connectivity for unmanned aerial vehicles (UAVs), a basic question is whether networks intended for terrestrial service can provide sufficient aerial coverage as well. To assess this possibility in the context of urban environments, extensive system-level simulations are conducted using a generative channel model recently proposed by the authors. It is found that standard downtilted base stations at street level, deployed with typical microcellular densities, can indeed provide satisfactory UAV coverage. Interestingly, this coverage is made possible by a conjunction of antenna sidelobes and strong reflections. As the deployments become sparser, the coverage is only guaranteed at progressively higher UAV altitudes. The incorporation of base stations dedicated to UAV communication, rooftop-mounted and uptilted, would strengthen the coverage provided their density is comparable to that of the standard deployment, and would be instrumental for sparse deployments of the latter.S. Rangan, W. Xia, S. Kang, and M. Mezzavilla were supported by NSF grants 1302336, 1564142, 1547332, and 1824434, NIST, SRC, and the industrial affiliates of NYU WIRELESS. A. Lozano and G. Geraci were supported by ERC grant 694974, by MINECO’s Project RTI2018-101040, by the Junior Leader Fellowship Program from “la Caixa" Banking Foundation, and by the ICREA Academia program. The work of V. Semkin was supported by the Academy of Finland
Oxide Solubility Minimum in Liquid Fe-M-O Alloy
No full textThe origin of the solubility minimum of oxide (MxOy) in liquid Fe-M-O alloy was investigated, and the minimum was predicted based on thermodynamic calculations. Due to the characteristic property of activities of M and 0 in the liquid, a maximum exists in the product between the two activities if the affinity of M to 0 is significantly high, as most deoxidizing elements are. A critical activity product is defined, which is an indicator of the solubility minimum of the MxOy in the liquid Fe-M-0 alloy according to the following relationship: max (a(M)(x) x a(O)(y)) = KMxO x Cliv4,0y, where the aM(x)O(y) is unity if the alloy is in equilibrium with the pure M(x)Oy(.) The origin of the solubility minimum was explained using the change of the activity product by composition. Available CALPHAD assessments for several binary Fe-Mliquid alloys and Wagner's solvation shell model were combined to calculate the activity product in the Fe-M-O alloy, which can be used to predict the solubility minimum of M(x)Oy. A favorable agreement was obtained when M = Al, B, Cr, Mn, Nb, Si, Ta, Ti, V, and Zr. The Gibbs energy of dissolution of O in pure liquid M (AgO(m)) and the Gibbs energy of the formation of Mx0y per mole of atoms (Delta g degrees M(x)Oy /(x + y)) play important roles in determining the solubility minimum, as long as an interaction between Fe and M is less significant than the interaction between metal (Fe and M) and 0. Predictions of the solubility minima of CaO and MgO were not satisfactory, requiring further improvement of the present analysis. (C) The Minerals, Metals & Materials Society and ASM International 201911Nsciescopu
G. M. Hopkins
No full text[sound recording] / Brendan O'Grady. G. B. Shaw by Fran Frazer.; 1 sound cassette (60 minutes); Broadcast on CFCY Radio, Charlottetown, March 07 & 11, 1974.; G. B. ShawSource type: Electronic(1
Choroterpes (Dilatognathus) nigella Kang & Yang 1994
No full textChoroterpes (Dilatognathus) nigella (Kang & Yang 1994) = Choroterpides nigella Kang & Yang 1994 = Dilatognathus/g(1) sp. 3: Kluge 2012 Material. THAILAND: province Mae Hong Son, river Namlang near Lot Cave, 12.I. 1998, coll. V. Ivanov: 17 larvae; province Muang Pai, river Pai, 11.I. 1998, coll. V. Ivanov: 7 larvae; SW Chiang Mai, Doi-Ithanon, river Klang, 17.I. 1998, coll. Grigorenko: 1 larva; national park Kaeng Krachan, river Pchetchabun, 26.II. 2006, coll. M. Chertoprud: 4 larvae. CHINA, HAINAN, Miao-Li, 19.XII. 1957, coll. N. Andrianova: 2 larvae (one of them with developing cuticle of next instar). Additional characteristics. Larva. Described by Kang & Yang (1994). Differs from all other species of Dilatognathus by shape of labrum, whose median incision is deep, semicircular and bordered by sharp semicircular impression on dorsal surface (Kang & Yang 1994: Fig. 3 A). Structure of maxillary apex in penultimolarva is the same as in ultimolarva: with long tusk bearing 3 vestiges of ventral pectinate setae, without ventro-apical flange and without dentiseta. Imago. Unknown. Egg. Described by Kang & Yang (1994). Dimension. Length of ultimolarva 6–10 mm. Distribution. Indochina Peninsula (Thailand), Hainan and Taiwan Islands. Discussion. Kang & Yang (1994) described Choroterpides nigella based on larvae and eggs. They did not compare Ch. nigella with Ch. minor. As characters distinguishing Ch. nigella from Ch. major, only two ones are named: (1) transversal curved row of long setae on labrum and (2) tooth-like maxillary tusk with three comb-like setae at its base. Actually, both characters are present in all Dilatognathus, including Ch. (D.) major (Ulmer 1939: Figs 262, 265).Published as part of Kluge, Nikita J., 2014, Indonesian species of Dilatognathus Kluge 2012 (Ephemeroptera, Leptophlebiidae, Choroterpes s. l.) and species-specific sexual dimorphism in development of maxilla in Zootaxa 3786 (1), DOI: 10.11646/zootaxa.3786.1.2, http://zenodo.org/record/23153
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