The diatom genus Thalassiosira: species from the San Francisco Bay system
(Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
Materials Literature
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Studies on borate esters IV. Structural analysis of borate esters of polyhydroxycarboxylates in water using 13C and 1H NMR spectroscopys
Abstract A combined 13 C and 1 H NMR study on borate esters of a series of polyhydroxycarboxylates is presented. 13 C substituent effects upon borate ester formation, as obtained from a set of model compounds, established that borate esters of the threo ‐3,4‐diol functions of gluconate, glucarate, idarate and probably…
Thermal decomposition of solid sodium bicarbonate
The thermal decomposition of solid sodium bicarbonate has been studied in the temperature range 360–500 K over a range of partial pressures of carbon dioxide. The effect of water vapour has also been studied. Above 440 K the reaction follows contracting-cube kinetics with an activation energy of 32 kJ mol–1 and a freq…
Scanning electron microscopy of uncoated fossils
(Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
Ecological studies on the littoral attaching micro-algae. VII. Adhesive strength of epiphytic diatoms on various seaweeds.
Epiphytic diatoms on the natural seaweeds (seven brown-algae, two red-algae and one green alga) were fractionated by the five step separating treatments of shaking and rubbing. The order of adhesive strength of diatom species was determined from the recovery patterns of each diatom obtained through the five step separ…
Inhibition of Pitting of Type 304L Stainless Steel by N‐Lauroylsarcosine
The resistance of Type 304L SS to localized corrosion by aqueous chloride solutions is increased by addition of N‐lauroylsarcosine (NLS). The effects of N‐lauroylsarcosine concentration, chloride concentration, p H, and metal surface prepassivation on the efficiency of pitting inhibition were investigated. Linear curr…
Structural Study on the Cubic to Tetragonal Transformation in Arc-melted ZrO<SUB>2</SUB>-3 mol%Y<SUB>2</SUB>O<SUB>3</SUB>
A herringbone structure observed in an as arc-melted specimen was investigated using XRD, TEM and surface relief study. The specimen was cooled on a water cooled copper hearth and the grain size was approximately 1 mm. The results confirmed the crystal structure to be tetragonal (at=0.5100 and ct=0.5166 nm, c⁄a=1.0129…
Properties of Mullite Powder Prepared by Coprecipitation and Microstructure of Fired Bodies
A mullite powder was prepared from aluminum isopropoxide and methyl silicate by coprecipitation using a dilute ammonium aqueous solution. Properties and microstructure of fired bodies were examined. The results were compared with those from a sol mixture (SM) and oxide mixture (OX). The coprecipitated powder (Cp), the…
Mechanism for the Dehydroxylation of Kaolinite, Dickite, and Nacrite from Room Temperature to 455°C
The mechanism for the dehydroxylation of Keokuk kaolinite, dickite, and nacrite (Al 2 Si 2 O 5 (OH) 4 ) was investigated in detail with the aid of powder X‐ray diffraction, the Rietveld method, and infrared spectroscopy. It was determined that these polymorphic clay minerals dehydroxylate via an inhomogeneous mechanis…
THE NUCLEATION OF MICROCELLULAR THERMOPLASTIC FOAM: PROCESS MODEL AND EXPERIMENTAL RESULTS
Microcellular polymer foams exhibit greatly improved mechanical properties compared to standard foams due to the formers' small bubble size. Typical microcellular foams have bubbles with diameters on the order of 10 microns and volume reductions of 30 to 40%. The presence of these bubbles acts to increase the impact s…
Structure–magnetism correlation in dimeric copper( II ) carboxylates: crystal and molecular structure of tetra-µ-(propanoato-O,O′)-bis[aquacopper( II )]
The dimeric copper(II) carboxylates [{Cu(O2CR)2(H2O)}2] and [{Cu(O2CR)2}2](R = Et or Prn) have been prepared and characterized by means of spectroscopic, magnetic, and thermogravimetric analyses. For [{Cu(O2CEt)2(H2O)}2] the crystal and molecular structure has also been determined. The crystals are monoclinic, space g…
Structural Investigation of Rapidly Quenched Li<sub>2</sub>O-B<sub>2</sub>O<sub>3</sub> Glasses by Raman Spectroscopy
Glasses were prepared over a wide range of composition in the system Li2O-B2O3 using a rapid quenching technique. The glass-forming region was extended up to the composition of 70mol% Li2O. Raman spectra of the glasses were measured; drastic spectral changes were observed in the glasses containing more than 50mol% Li2…
Structural change of orthorhombic-Itridymite with temperature: A study based on second-order thermal-vibrational parameters
X-ray studies of orthorhombic- I tridymite, especially focussed on atomic mean-square displacements (m.s.d.'s) at 443, 493, 573, 653 and 693 K respectively, were carried out on the basis of the usual second-order refinement of the Dollase model. The m.s.d.'s for O are highly anisotropic, and large in the planes perpen…
Na5FeS4 – das erste Thioferrat(III) mit diskreten tetraedrischen Anionen
Abstract Rubinrote Kristalle der Verbindung Na 5 FeS 4 lassen sich durch Umsetzung von Natriumsulfid mit Eisen und Schwefel bei 970 K darstellen. Röntgenographische Strukturuntersuchungen an einem Einkristall führten zu einer dem ternären Oxid Na 5 GaO 4 entsprechenden Atomanordnung [1]. Na 5 FeS 4 kristallisiert rhom…
Collagen and Elastin Synthesis in Human Stroma and Breast Carcinoma Cell Lines: Modulation by the Extracellular Matrix
The desmoplastic response to breast carcinoma is being studied. The stimulation of stromal cell proliferation by a preformed breast tumor matrix was shown. An additional mechanism for stimulating scleroprotein deposition is described here. On a per-cell basis, the synthesis of collagen and elastin was increased by 50%…
Charge-density wave transport
The unusual electrical properties of certain inorganic compounds which behave as quasi-one-dimensional metals are reviewed, with emphasis on the evidence which they provide for conduction by the cooperative mechanism, involving the motion of incommensurate charge-density waves (CDWs), first suggested by Frohlich (1954…
Particle-Initiated Breakdown Characteristics and Reliability Improvement in SF6 Gas Insulation
Particle-initiated breakdown characteristics in SF6 gas are investigated. Breakdown voltages are greatly influenced by particle diameter especially for AC voltages, and for very fine metallic wire particles are much higher than those for moderately thick ones. The breakdown stress of a gas gap is obtained as a functio…
Ordered solution structure of a monodispersed polystyrene latex as studied by the transmitted light spectrum method
The microstructure of monodispersed polystyrene latices in deionized solution has been systematically investigated by the transmitted light spectrum method. Latices used are between 85 and 246 nm in diameter and the charge density of the latex surface is between 1.0 and 36 µC cm–2. Clear peaks showing the selective Br…
Binuclear nickel( II ) and cobalt( II ) complexes of the novel binucleating ligand 3,6-bis(1′-pyrazolyl)pyridazine. Crystal and molecular structure and magnetism of bis[µ-3,6-bis(1′-pyrazolyl)pyridazine-N 1 (Ni 1 )N 2 ′(Ni 1 )N 2 (Ni 2 )N 2 ″(Ni 2 )]bis[diaquanickel( II )] tetrachloride dihydrate
Reaction of the ligand 3,6-bis(1′-pyrazolyl)pyridazine (ppd) with nickel(II) and cobalt(II) salts produces binuclear derivatives in which the two pseudo-octahedral metal centres are bound simultaneously between two adjacent ligands in a doubly bridged structure. The complex [Ni2(ppd)2(H2O)4]Cl4·2H2O (1) crystallizes i…
Solidification Microstructure of Y<SUB>2</SUB>O<SUB>3</SUB>-Added Al<SUB>2</SUB>O<SUB>3</SUB>–ZrO<SUB>2</SUB> Eutectic
The microstructure of the Al2O3–ZrO2 eutectic with addition of a small amount of Y2O3 has been studied. The eutectic composition was determined as 59 mol%Al2O3–36.8 mol%ZrO2–4.2 mol%Y2O3. The added Y2O3 (2.1–5.3 mol%) dissolved only in the ZrO2 phase and the crystal structure of this phase changed from monoclinic to t…