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Note on the morphology of two planktonic diatoms: Chaetoceros bacteriastroides and C. seychellarus, with comments on their taxonomy and distribution

David U. Hernández‐Becerril1993-02-01Botanical Journal of the Linnean Society

Two planktonic species of diatoms, Chaetoceros bacteriastroides and C. seychellarus , have been studied by light and electron microscopy. Important features that may be used as taxonomic characters are described. A new subgenus, Bacteriastroidea, is proposed to include C. bacteriastroides, because of its unique charac…

Diatoms and Algae Research

2 × 2 propagation matrix for electromagnetic waves propagating obliquely in layered inhomogeneous uniaxial media

Hiap Liew Ong1993-02-01Journal of the Optical Society of America A

A 2 × 2 propagation-matrix formalism for finding the obliquely propagating electromagnetic fields in layered inhomogeneous uniaxial structures is presented. The 2 × 2 propagation matrix was produced by our generalized geometrical-optics approximation method. A 2 × 1 field vector for the transverse electric field is de…

Liquid Crystal Research AdvancementsPhotonic Crystals and ApplicationsOptical Polarization and Ellipsometry

The Analgesic Activity ofHedyosmum bonplandianum: Flavonoid Glycosides

Luz Clarena Cárdenas、Jaime Rodrı́guez、M. Carmen Villaverde 等 6 位作者1993-02-01Planta Medica

Kaempferol 3-O-[alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside] and kaempferol 3-O-[beta-D-glucopyranoside] were isolated from the leaves of Hedyosmum bonplandianum H.B.K. (Chloranthaceae), which is used in Colombian folk medicine as an analgesic. The n-butanol extract and the glycosyl flavonoids isolated exhi…

Phytochemistry and Bioactive CompoundsPsidium guajava Extracts and Applications

Structure and behaviour of SiO2/MgCl2 bisupported Ziegler‐Natta catalysts for olefin polymerization

Honglan Lu、Shijing Xiao1993-02-01Die Makromolekulare Chemie

Abstract Bisupported catalysts for olefin polymerization were prepared by mixing a butyl alcoholate solution of MgCI 2 with pretreated SiO 2 in heptane, and further treating with TiCI 4 solution. The silica pretreating conditions and their effects on the composition of the catalysts were studied. The interaction mecha…

Organometallic Complex Synthesis and Catalysisbiodegradable polymer synthesis and propertiesSynthetic Organic Chemistry Methods

Thecal apex structure in the Peridiniaceae (Dinophyceae)

Saburo Toriumi、John D. Dodge1993-02-01European Journal of Phycology

Scanning electron microscopy has been used to observe the details of the apical structure of the theca in 46 species belonging to 10 genera (Boreadinium, Diplopsalis, Diplopsalopsis, Dissodium, Lebouraia, Oblea, Peridiniopsis, Peridinium, Protoperidinium, Zygabikodinium) in the family Peridiniaceae (Dinophyceae). The…

Marine and coastal ecosystemsMarine Toxins and Detection MethodsDiatoms and Algae Research

Electrochemical and spectroelectrochemical characterization of (5,10,15,20-tetrakis(1-methyl-4-pyridyl)porphinato)manganese(III) chloride, [(TMpyP)MnIIICl]4+(Cl-)4, in N,N-dimethylformamide

Eric Van Caemelbecke、Włodzimierz Kutner、Karl M. Kadish1993-02-01Inorganic Chemistry

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectrochemical and spectroelectrochemical characterization of (5,10,15,20-tetrakis(1-methyl-4-pyridyl)porphinato)manganese(III) chloride, [(TMpyP)MnIIICl]4+(Cl-)4, in N,N-dimethylformamideEric Van Caemelbecke, Wlodzimierz Kutner, and Karl M. KadishCite this: Inorg. Chem. 19…

Electrochemical sensors and biosensorsPorphyrin and Phthalocyanine ChemistryElectrochemical Analysis and Applications

Synthesis and Mesomorphic Properties of 3,5-bis-(p-n-Alkoxyphenyl)lsoxazole and 3,5-bis-(p-n-Alkoxyphenyl)Pyrazole

J. Bartulín、Roberto Martı́nez、Hugo Gallardo 等 5 位作者1993-02-01Molecular crystals and liquid crystals science technology. Section A, Molecular crystals and liquid crystals/Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals

The synthesis and mesomorphic behavior of 3,5-bis-(p-n-alkoxyphenyl)isoxazole (series I) and 3,5-bis-(p-n-alkoxyphenyl)pyrazole (series II) are reported for the number of carbon atoms (n) in the alkoxy chains varying from three to eight. Series I shows an enantiotropic nematic phase for all n and an enantiotropic smec…

Liquid Crystal Research AdvancementsMolecular spectroscopy and chiralityAxial and Atropisomeric Chirality Synthesis

Alkylene Polyimides for Aligning Nematic Liquid Crystals: Anomalous Odd-Even Effect in Tilt Bias Angles as a Function of Chain Length of Alkylenes

Hisao Yokokura、Masahito Oh‐e、K. Kondo 等 4 位作者1993-02-01Molecular crystals and liquid crystals science technology. Section A, Molecular crystals and liquid crystals/Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals

Measurements of tilt bias angles of a nematic liquid crystal were carried out, by using several alkylene polyimides synthesized from 3,3′,4,4′-biphenyltetracarboxylic dianhydrides and diamines with different chain lengths as alignment layers. The tilt bias angle dependence on the alkylene chain length of polyimides sh…

Liquid Crystal Research AdvancementsPhotonic Crystals and ApplicationsSynthesis and properties of polymers

Liquid-crystalline and thermochromic behaviour of 4-substituted 1-methylpyridinium iodide surfactants

Jan Jaap H. Nusselder、Jan B. F. N. Engberts、Henk A. van Doren1993-02-01Liquid Crystals

The mesogenic behaviour of a series of thirty-one 1-alkyl-4-(or 2-)alkylpyridinium salts and of a homologous series of four 1-methyl-4-n-alkoxycarbonylpyridinium iodides is described. The occurrence and stability range of the thermotropic phases depend dramatically on the structure of the surfactants. Mesophases are o…

Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsMolecular spectroscopy and chirality

Nonlinear effects in the dynamics of shape and volume oscillations for a gas bubble in an external flow

Su‐A Yang、Z. C. Feng、L. Gary Leal1993-02-01Journal of Fluid Mechanics

This paper considers the dynamics of a gas bubble in response to either a pressure pulse or a pressure step at t = 0, both in the presence and absence of a mean flow. Our work utilizes small-deformation, domain perturbation analysis carried to second and higher order in the amplitude of deformation, ε. In the absence…

Fluid Dynamics and Heat TransferUltrasound and Cavitation PhenomenaParticle Dynamics in Fluid Flows

Critical points in layered systems

Anne-Dominique Defontaines、Jacques Prost1993-02-01Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Critical points that do not involve any symmetry change are shown to define a set of new universality classes in layered systems. Extension of this problem to higher dimensions may be made in an infinite number of ways which define continuously varying upper critical dimensions. This allows us to estimate uncertaintie…

Liquid Crystal Research AdvancementsSpectroscopy and Quantum Chemical StudiesMolecular spectroscopy and chirality

Comparison of Modeling Approaches for a Porous Salt Film

Alan C. West1993-02-01Journal of The Electrochemical Society

In most models of anodically formed salt films, the concentrations of the ionic components of the salt are assumed to be at their saturation values at the film/electrolyte interface. The consequences of also imposing the saturation condition inside a porous film are compared to results of the more commonly employed mo…

Corrosion Behavior and InhibitionEnhanced Oil Recovery TechniquesMinerals Flotation and Separation Techniques

Construction of Dynamic Conoscope Observation System Using CCD Camera and Image Processor

Takayuki Fujikawa、Kazuyuki Hiraoka、Tadaaki Isozaki 等 6 位作者1993-02-01Japanese Journal of Applied Physics

In order to study the dynamic behavior of conoscopic images with high precision and high efficiency, we constructed a conoscope observation system using a CCD (charge coupled device) camera and an image processor. We can analyze biaxiality and apparent tilt angle by means of a homeotropic cell operated at 0.1 Hz. We d…

Liquid Crystal Research AdvancementsOptical Polarization and EllipsometryMolecular spectroscopy and chirality

Lyotropic mesophase of imogolite, 3 observation of liquid crystal structure by scanning electron and noval polarized optical microscopy

Nobuo Donkai、Hiroshi Hoshino、Kanji Kajiwara 等 4 位作者1993-02-01Die Makromolekulare Chemie

Abstract The mesophase (lyotropic liquid crystal) of the inorganic rod‐like polymer, imogolite, displays a typical fingerprint texture under a polarized optical microscope (POM), although the mesophase reveals no circular dichroism. The scanning electron microscope revealed a honeycomb structure of thin sheets having…

Liquid Crystal Research Advancements

Polyesterification reactions of adipic acid‐based polyesters

Wally L. Chang、Tom Karalis1993-02-01Journal of Polymer Science Part A Polymer Chemistry

Abstract A series of studies of uncatalyzed and catalyzed polyesterification experiments have been investigated using different glycols at different temperatures. The experimental results for uncatalyzed reactions agreed quite well with the kinetic equation as proposed by P. J. Flory. However, Flory proposed a second‐…

Organometallic Complex Synthesis and Catalysisbiodegradable polymer synthesis and propertiesCarbon dioxide utilization in catalysis

Boxwork Fabric of Halloysite-Rich Kaolin Formed by Weathering of Anorthosite in the Sancheong Area, Korea

Gi Young Jeong、Soo Jin Kim1993-02-01Clays and Clay Minerals

Abstract Boxwork fabric in which numerous thin or thick halloysite walls are interconnected into a microscopically porous cellular pattern is widely developed in the halloysite-rich kaolin formed by weathering of anorthosite in Sancheong, Korea. Studies using optical microscopy, scanning electron microscopy, and trans…

Clay minerals and soil interactionsIron oxide chemistry and applicationsMineralogy and Gemology Studies

Water accumulation in the alcohol extraction of cottonseed

G N Abraham、R. J. Hron、M. S. Kuk 等 4 位作者1993-02-01Journal of the American Oil Chemists Society

The critical moisture content of cottonseed flakes extracted with an aqueous alcohol solvent can be defined as that flake moisture level at which the flakes lose no moisture during extraction. This study shows that the critical moisture content for aqueous ethanol (92%, w/w) is 3%. For aqueous isopropanol (88%, w/w) t…

Textile materials and evaluationsResearch in Cotton Cultivation

Adsorption of palladium-ammino-aquo complexes on .gamma.-alumina and silica

D. Spielbauer、H. Zeilinger、H. Knoezinger1993-02-01Langmuir

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAdsorption of palladium-ammino-aquo complexes on .gamma.-alumina and silicaD. Spielbauer, H. Zeilinger, and H. KnoezingerCite this: Langmuir 1993, 9, 2, 460–466Publication Date (Print):February 1, 1993Publication History Published online1 May 2002Published inissue 1 February…

Analytical chemistry methods developmentCorrosion Behavior and InhibitionMesoporous Materials and Catalysis

Swinging of the bent nitrosyl ligand in (nitrosyl- 15N)(meso-tetraphenylporphinato)cobalt: a solid-state motion detected by nitrogen-15 CPMAS NMR spectroscopy

Christopher J. Groombridge、Leslie F. Larkworthy、Joan Mason1993-02-01Inorganic Chemistry

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSwinging of the bent nitrosyl ligand in (nitrosyl- 15N)(meso-tetraphenylporphinato)cobalt: a solid-state motion detected by nitrogen-15 CPMAS NMR spectroscopyChristopher J. Groombridge, Leslie F. Larkworthy, and Joan MasonCite this: Inorg. Chem. 1993, 32, 4, 379–380Publicati…

Magnetism in coordination complexesPorphyrin and Phthalocyanine ChemistryElectron Spin Resonance Studies

A geometrical constraint approach for reproducing the native backbone conformation of a protein

Shin Saitoh、Takahisa Nakai、Ken Nishikawa1993-02-01Proteins Structure Function and Bioinformatics

It is known that the backbone conformation of a protein can be reproduced with precision once a correct contact map (two-dimensional representation showing residue pairs in contact) is given as geometrical constraints. There is, however, no way to infer the correct contact map for a protein of unknown structure. We st…

Protein Structure and DynamicsRNA and protein synthesis mechanismsEnzyme Structure and Function