Rectangular Shape (rectangular + shape)

Distribution by Scientific Domains


Selected Abstracts


Crystal growth features and properties of layered rare earth and barium cobaltates

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 4-5 2005
G. L. Bychkov
Abstract High quality single crystals of LnBaCo2O5+, (0 < , < 1) (Ln = Pr, Eu, Gd, Tb, Dy) with rectangular shape and average dimensions 5 mm × 5 mm × 1 mm were grown for the first time from overstoichiometric flux melt. The data on the primary crystallization field of most cobaltate phases, which appear in parts of corresponding Gibbs triangles in the range 1373 , 1523 K are discussed. Bulk single crystals of new phases HoBaCo4O7 up to 300 mm3, YBaCo4O7 and TbBaCo4O7 up to 10 mm3 in volume were grown first. A solution of these compounds structure has been found in the space group P63mc. For the Ln = Pr, Gd, Sm, Tb, Dy, Ho based systems under the liquidus line there are several other new cobaltate phases of both perovskite, and hexagonal crystal structure. Stability of the double perovskite phase and temperature of the antiferromagnetic , ferromagnetic phase transition in relation to the radius of rare earth ions are compared. The data on the exact analysis of chemical composition, including EDX and iodometric titration, as well as results on magnetic susceptibility of EuBaCo1- xAlxO5+, (0 < x < 0.3) are discussed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Crescent Versus Rectangle: Is It a True Negative Margin in Second and Subsequent Stages of Mohs Surgery?

DERMATOLOGIC SURGERY, Issue 2 2010
YUE YU MD
BACKGROUND The hallmark of Mohs micrographic surgery is using tangential tissue sections that theoretically allow 100% of the tissue margin to be examined, but when taking additional layers for second and subsequent Mohs stages, no detailed methods have been described to ensure that 100% of the tissue margins are analyzed. METHOD A rectangular or a crescent-shaped layer is often used to take second and subsequent stages. Here we compare the two techniques for their theoretic advantages and disadvantages. SUMMARY The advantage of the rectangular shape has been ease of processing, as well as built in vertical "nicks" that automatically mark the border of the tissue removed, but the rectangular layer may not provide 100% evaluation of the tumor margin because the vertical edges of the rectangular layer are not always completely analyzed, and thus tumor cells cannot be visualized in the vertical margins of these layers. This might result in a false-negative margin reading, which can be avoided by using the crescent layer. CONCLUSION We propose taking second and subsequent Mohs layers with only a crescent shape, which allows true 100% tissue margin assessment. The authors have indicated no significant interest with commercial supporters. [source]


Effect of Minimal Processing Conditions on Respiration Rate of Carrots

JOURNAL OF FOOD SCIENCE, Issue 8 2008
T. Iqbal
ABSTRACT:, Measurement, analysis, and modeling of respiration rate (RR) of fresh produce are fundamental for the engineering design of MAP. This study investigates the effect of type of cutting (sliced in circular shape, batons in rectangular shape, and shredded into thin strips) on the respiration rate of carrots at different temperatures (4, 8, 12, 16, and 20 °C) with ambient atmosphere. The higher respiration rates were found for shredded carrots and the lowest for whole carrots at all the temperatures tested. The RR increased from 9 ± 1 to 26 ± 3, 10 ± 1 to 53 ± 2, 11 ± 1 to 55 ± 2, and 18 ± 1 to 75 ± 3 mL of O2 per kilogram hour for whole, sliced, baton, and shredded carrots, respectively, as the temperature increased from 4 to 20 °C. On an average, RO2 and RCO2 were increased by 85% and 64%, 100% and 72%, and 151% and 124% for sliced, baton, and shredded carrots, respectively, compared to the RR values of whole carrots. The temperature dependence of RR followed an Arrhenius-type relationship for all types of carrots, with activation energies in the range of 35 ± 3 to 62 ± 2 kJ/mol. Type of cut was the major factor for both RO2 and RCO2, with shredded carrots having the highest rates and whole carrots the lowest. RR of whole carrots did not vary during storage, whereas it increased for cut carrots and especially for shredded carrots. The respiratory quotient (RQ) increased with temperature and did not vary during storage in all types of carrots, except the RQ of whole carrots decreased significantly over time. [source]


Uniaxial Testing and the Performance of a Pallet Press

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 2 2003
G.G. Enstad
Abstract It is a common problem that powders become aerated during filling into sacks, causing increased volumes, low mechanical stability, bursting of sacks, dusting as air escapes, difficulties in palletizing, and stacking of the pallets. In order to overcome such problems, a pallet press was developed several years ago. The press is used to obtain a more uniform geometry and to get rid of excess air from palletized sacks by simply pressing the pallets into a rectangular shape. How a powder will behave during filling into sacks will depend on its properties. By testing the powders to be stored in this way, one can predict what advantages can be obtained by using the pallet press for specific powders. The applicability of a uniaxial tester, developed for testing flow properties of powders, has been investigated for this purpose by Tel-Tek, POSTEC dept. [source]


Highly Periodic Fullerene Nanomesh,

ADVANCED MATERIALS, Issue 2 2006
N. Néel
Fullerene nanomesh: Fullerene islands with rectangular shapes organize themselves on a vicinal gold surface in an extraordinarily well-ordered mesh with unprecedented periodicity and low defect density (see Figure). This adsorbate system is a promising candidate for guiding subsequent deposition of functional units. [source]