bluuebunny/crossref_metadata_2025_split huggingface dataset:
Natural convection in a shallow laterally heated air‐filled cavity
Authors: Wright N. G. , Gaskell P. H. , Sleigh P. A. 
Published: August 2005

AbstractThe flow in a shallow, laterally heated air‐filled cavity is investigated numerically using a primitive variable formulation of the governing equations of motion. Solutions are obtained for the entire flow field using a coupled solver combined with an FAS non‐linear multigrid convergence accelerator. While care is taken to use a high‐order, bounded discretization scheme for convective transport, the overall stability and efficiency of the approach is enhanced through the use of defect correction. This combination of features enables solutions to be found on extremely fine grids. Results for the flow in the end region of such cavities are compared qualitatively with the predictions of asymptotic theory for large aspect ratio, A (length:height), up to values of A higher than previously reported (A= 100); the particular case of A = 20 is considered for Rayleigh numbers in the range 103 to 108. Finally it is demonstrated how such solutions can be further enhanced by using locally refined grids in the end regions.
Smooth modelling of the normal vector by using C0‐continuous lagrange elements in BEM
Authors: Sladek V. , Sladek J. 
Published: August 2005

AbstractThe paper reveals the conditions under which the approximations of the normal vector and global coordinates of interior points of two segments on a smooth contour can fail using the C1‐continuous Overhauser elements. A new continuous modelling of the normal vector is developed using the standard Lagrange elements. The derivation is consistent with the assumptions employed in the boundary element method formulations of potential problems. Test numerical examples are considered in order to analyse the accuracy of the approximations based on the use of standard C0‐continuous elements, Overhauser C1‐continuous elements and the proposed ‘smooth’ C0 elements.
A patch test for mesh alignment effects in localized failure
Authors: Pastor M. , Quecedo M. 
Published: August 2005

AbstractComputation of failure mechanisms is of paramount importance for engineers assessing safety of structures. However, computation of failure loads and mechanisms presents numerical difficulties leading to wrong answers, especially in the case where failure consists in localization of plastic deformation or damage in localized zones. Here, the results depend on factors like mesh alignment and element distortion. The paper addresses the problem of designing a suitable patch test to assess element performance under localized failure. It will be shown how predictions of this test provide a reliable answer to the question of whether a particular element will or will not be suitable for such failure computations.
Line follower for finite element postprocessing and current imaging
Authors: Sepulveda N. G. , Wikswo J. P. 
Published: August 2005

AbstractThe display of isopotential contours is a standard technique in the interpretation of results generated by the finite element analysis of voltage distribution problems. The complementary display of the current flow or flux lines is in many ways more useful intuitively, but has not been used widely in finite element analyses. We describe a simple method for generating flux line distributions, and discuss the method as applied to the reconstruction of current distributions from magnetic field maps.
Numerical modeling and investigation of liquid phase epitaxy of Hg1–xCdxTe infrared detectors
Authors: Lin K. , Dold P. , Figgemeier H. , Benz K. W. 
Published: August 2005

AbstractNumerical investigations have been performed for modeling the global temperature field of an industrial liquid phase epitaxy (LPE) facility and to estimate the temperature fluctuations in a Te‐rich solution during the LPE growth. The numerical results agreed well with experimental data and therefore provide reliable reference points for experimenters for further improvements of the growth conditions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The influence of supersaturation on crystal morphology – experimental and theoretical study
Authors: Lu Jun Jun , Ulrich Joachim 
Published: August 2005

AbstractThe surface docking approach of molecular modeling for prediction of crystal morphology in the presence of additives is further developed in this work. It is modified in order to take into account the influence of supersaturation on the crystal habit. With the introduction of the BCF theory and the 2‐D growth mechanism in the above mentioned approach predictions have been carried out for paracetamol and caprolactam crystals, respectively. The verifications by crystals grown from solutions as simulated by the computer model give good agreements. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and optical characterization of cerium and lead‐doped Bi12TiO20 sillenite single crystals
Authors: Carvalho J. F. , Hernandes A. C. 
Published: August 2005

AbstractBi12TiO20 (BTO) single crystals doped with PbO and CeO2 were grown by the Top Seeded Solution Growth (TSSG) technique from the liquid phase with nominal compositions of 10Bi2O3 : (1–x)TiO2 : x PbO and 10Bi2O3 : (1–x)TiO2 : xCeO2 with x = 0.25 and 0.10. No growth‐related difficulties were encountered other than those typical of sillenite crystals. Samples with good optical quality were obtained and were characterized by optical absorption, dark current, spectral photocurrent dependence, optical activity and electro‐optic coefficient measurements. A comparison is made of the results of the optical measurements of doped and undoped BTO crystals. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the void distribution and size in shaped sapphire crystals
Authors: Bunoiu O. M. , Nicoara I. , Santailler J. L. , Theodore F. , Duffar T. 
Published: August 2005

AbstractRibbon and rod sapphire pulling has been performed in three different crystal growth equipments in order to study the effect of the installation, of the atmosphere, of the die shape, of the feed material and of the pulling rate on the distribution, number and diameter of the characteristic voids (micro‐bubbles) in the crystals. The location of the bubbles in the crystals depends on the die geometry; however, in most cases they are essentially located close to the crystal periphery and then can be efficiently removed by lapping. After statistical analysis of the results, it is demonstrated that the number of gas moles incorporated in the crystals, inside the voids, is totally independent of any growth parameter. It is also shown that the bubble diameter depends only on the pulling rate. Consequently, for a given pulling rate, the number of bubbles auto‐adjusts in order to satisfy the constant molar gas incorporation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of cetyl pyridinium chloride additive on crystallization of gypsum in phosphoric and sulfuric acids medium
Authors: El‐Shall H. , Rashad M. M. , Abdel‐Aal E. A. 
Published: August 2005

AbstractA basic study was carried out to understand effect of Cetyl Pyridinium Cloride (CPC) on calcium sulfate dihydrate (gypsum) crystallization. Induction time was measured under different supersaturation ratios ranging from 1.222 to 1.979. This is the time elapsed between the achievement of supersaturation and the appearance of a solid phase. The results show that, the induction time decreases exponentially with increasing the supersaturation ratio. In addition, the surface energy increases with CPC compared to the baseline (without CPC). Number of molecules required for formation of stable nucleus are calculated to be from 3 to 41 molecules depending on supersaturation ratios and presence of CPC. Interestingly, with addition of the CPC, the mean diameter of the crystals and the median increase. The growth rate was found dependent on the supersaturation with and without CPC. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermodynamic feasibility study for chemical vapour deposition of some ternary crystals using iodine and hydrogen iodide
Authors: Kunjachan S. , Korah I. , Ittyachen M. A. 
Published: August 2005

AbstractThermodynamic feasibility of transition metal dichalcogenide (TMDC) single crystals of Cu Al S2, Cu Al Se2, Cu Al Te2, Cu Ga S2, Cu Ga Se2, Cu Ga Te2, Cu In S2, Cu In Se2, Cu In Te2, Ag Ga S2, Ag Ga Se2, Ag Ga Te2, Ag In Se2, Ag In Te2, using iodine and hydrogen iodide as transporting agents has been reported in this paper. Results give range of temperature for the iodide transport and prevention of starting material formation (elemental transport) in the growth zone. From the range of temperature for the growth of crystals, selected source zone and growth zone temperatures with a differential of 100 °C are also listed. Referring the data listed in the tables can grow good quality crystals. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
HigHighly strained InGaAs/GaAs quantum wells emitting beyond 1.2 µm
Authors: Sharma T. K. , Zorn M. , Zeimer U. , Kissel H. , Bugge F. , Weyers M. 
Published: August 2005

AbstractHighly strained InxGa1–xAs quantum wells (QWs) with GaAs barriers emitting around 1.2 µm are grown on GaAs substrates by metal organic vapour phase epitaxy (MOVPE) at low growth temperatures using conventional precursors. The effects of growth temperature, V/III ratio and growth rate on QW composition and luminescence properties are studied. The variation of indium incorporation with V/III ratio at a growth temperature of 510 °C is found to be opposite to the results reported for 700 °C. By an appropriate choice of the growth parameters, we could extend the room temperature photoluminescence (PL) wavelength of InGaAs/GaAs QWs up to about 1.24 µm which corresponds to an average indium content of 41% in the QW. The results of the growth study were applied to broad area laser diodes emitting at 1193 nm with low threshold current densities. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micromorphology of pure and PbI2‐doped CdI2 dendritic single crystals
Authors: Kumar Binay , Sinha Nidhi 
Published: August 2005

AbstractUndoped and PbI2‐doped dendritic single crystals were grown by vapour growth technique. The basal surfaces of the as grown crystals were examined by optical and electron microscopy to observe wide variety of growth and defect features. Apart from typical features of dendritic growth, features of overgrowth, slip bands, growth steps and their bunching, etc. were observed. The basal surfaces of the crystals were then etched by controlled condensation of water vapour, after optimizing the etching condition, and the microscopic studies were repeated. Etch pits of hexagonal and triangular shape, both symmetric and asymmetric, and of different density, were observed in the case of undoped and doped crystals, respectively. In some cases, crystallographic hillocks were also observed. The crystals were also examined by X‐ray diffraction for their polytypism and related behaviour. The results are analyzed to elicit information on the correlation of structure, defects and surface features of the crystals. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical anisotropy in GaSe
Authors: Seyhan A. , Karabulut O. , Akįnoğlu B. G. , Aslan B. , Turan R. 
Published: August 2005

AbstractOptical anisotropy of the layer semiconductor GaSe has been studied by photoluminescence (PL) and Fourier Transform Infrared Spectroscopy (FTIR). The PL spectra are dominated by two closely positioned emission bands resulting from the free exciton and the bound exciton connected direct band edge of GaSe. Photoluminescence and transmission spectra of GaSe crystals have been measured for two cases in which the propagation vector k is perpendicular (k ⟂ c) and parallel to the c‐axis (k // c). Peak position of the PL emission band and the onset of the transmission have been found to be significantly different for these two cases. This observed anisotropy is related to anisotropic band structure and the selection rules for the optical absorption in layered GaSe. FTIR transmission spectrum is in good agreement with PL results. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flow cytogenetic studies in chromosomes and whole cells for the detection of clastogenic effects
Authors: Otto Friedrich J. , Oldiges Hubert 
Published: August 2005

AbstractFlow cytometric measurements of the chromosomal DNA content have been used to develop a screening method for the detection of chemically‐ or physically‐induced cytogenetic damage. The reproducibility of this flow cytogenetic assay was shown in a series of subcultures of a Chinese hamster cell clone. The accuracy and sensitivity was tested in cultures treated with chemical mutagens and x‐rays. The clastogenic effectiveness was quantified and the dose‐effect relationship was established by the increase of the coefficient of variation of the peak of the largest chromosome type in the flow histograms. Since structural chromosome aberrations cause an unequal division of the DNA at mitosis, it is expected that clastogenic effects can be detected also in whole cells of growing populations as an increased dispersion of the cellular DNA content. In order to test this feature, high resolution flow cytometric measurements were performed in x‐irradiated hamster cells in vitro and mouse bone marrow cells in vivo.
Intracytoplasmic immunofluorescence in multiple myeloma
Authors: Zeile G. 
Published: August 2005

AbstractA new intracytoplasmic immunofluorescence staining procedure has been investigated to detect and quantify myeloma cells by means of flow cytometry. Freshly harvested bone marrow aspirations from 12 patients with multiple myeloma were treated with collagenase and Triton X‐100, and incubated with different specimens of fluoroisothiocyanate‐marked antihuman immunoglobulins. DNA‐staining was then done with propidium iodide. Biparametric evaluation in a Cytofluorograf 6300 A/FC 200 showed a characteristic cluster distribution of normal and pathological immunoglobulin‐producing cells. This intracytoplasmic fluorochromic staining procedure may be significant for the specific identification of nonsecretive immunocytomas, which cannot be detected by serodiagnostic methods.
Automated absorption image cytometry of electromagnetically exposed frog erythrocytes
Authors: Chiabrera A. , Viviani R. , Parodi G. , Vernazza G. , Hinsenkamp M. , Pilla A. A. , Ryaby J. , Beltrame F. , Grattarola M. , Nicolini C. 
Published: August 2005

AbstractFrog erythrocytes dedifferentiate in vitro when exposed to a suitable electromagnetic field in a chemically potentiated microenvironment. These electrochemical stimuli are able to induce a chromatin decondensation, as previously shown by measuring the chromatin accessible sites for acridine orange intercalation by means of flow cytometry (acridine orange green fluorescence). Automated absorption image cytometry of Feulgen stained smeared erythrocytes has been performed to further elucidate the above processes. After measuring or computing the area A of the nucleus, which is related to its volume, the nucleic integrated optical density D, which is related to the DNA content, the average optical density DA = D/A, which is related to chromatin conformation, and the accessible chromatin sites SA = D2/3 A1/3, the following results have been obtained: (a) electromagnetically exposed cells progress to stages which correspond to values of D equal to those of controls, in the potentiating solution, whereas A increases, so that DA is smaller in exposed erythrocytes than in control ones, confirming that chromatin decondensation is occurring as an early dedifferentiation step. (b) By using the electromagnetic signal that is most effective in promoting dedifferentiation, erythrocytes further progress toward more advanced stages, which correspond to larger values of both D and A than in controls, i.e., to larger DNA content. (c) In all cases, the histograms of SA are in agreement with those previously obtained by flow microfluorometry of chromatin conformation (acridine orange green fluorescence). Finally, flow microfluorometric measurements of acridine orange red fluorescence give an increase of RNA content for case (a), as compared with controls, and for case (b) as compared with (a). These results point out that frog erythrocytes can be electromagnetically reactivated, resuming both RNA and DNA syntheses after initial chromatin decondensation.
A model for the computer analysis of synchronous DNA distributions obtained by flow cytometry
Authors: Fox Michael H. 
Published: August 2005

AbstractA new model for obtaining the distributions of cells in the cell cycle by computer analysis of flow cytometry data is proposed. The model is able to analyze distributions from both asynchronous and synchronous cell populations. A culture of HeLa cells is pulse‐labeled with tritiated thymidine at various times after sychronization by the mitotic selection method, then analyzed by flow cytometry and autoradiography. The results show good agreement between the percentage S‐phase cells determined by the model and by autoradiography.
Selection of viable cells with known DNA content
Authors: Hamori Eugene , Arndt‐Jovin Donna J. , Grimwade Brian G. , Jovin Thomas M. 
Published: August 2005

AbstractCells doubly stained with Hoechst 33342 (H‐33342) for DNA content and fluorescein diacetate for viability can be selected on the basis of both criteria using a single UV laser flow sorter. The selection is made possible due to resonance energy transfer occurring between the H‐33342 and fluorescein fluorophores. Both a static fluorescence microscope and a dual laser flow sorter were used to demonstrate that energy transfer occurs in the doubly stained cells and that the sensitized emission in conjunction with the DNA emission can be used to select populations of cells with known DNA content and viability. The results indicate that fluorescein liberated by cellular esterases is freely accessible to the nucleus.
Percentage of cells in the S phase of the cell cycle in human lymphoma determined by flow cytometry. Correlation with labeling index and patient survival
Authors: Braylan Raul C. , Diamond Lawrence W. , Powell Marie L. , Harty‐Golder Barbara 
Published: August 2005

AbstractThe percentage of cells with S phase DNA content (S cells) was determined by flow cytometry in cell suspensions obtained from 27 patients with non‐Hodgkin's lymphomas. DNA was measured in ethanol‐fixed cells stained with propidium iodide after RNase treatment. Cells from 17 samples were also exposed to [3H]‐thymidine and labeling indices were determined. An excellent linear correlation was observed between the percentage of S cells calculated by flow cytometry and the labeling index (r = 0.95). To determine the relationship between the percentage of S cells and the clinical behaviour of the tumors, the survival of the 27 patients was analyzed. None of the patients was undergoing antineoplastic therapy at the time of the study. The patients were separated into 2 groups according to the percentage of S cells calculated by flow cytometry: those with less than 5% S cells and those with higher than 5% S cells. Clinical follow‐up ranged from 5 to 20 months. While 7 of 12 patients with tumors containing more than 5% S cells have died of lymphoma (median survival, 9 months), there has been only one death from lymphoma among 15 patients with tumors containing less than 5% S cells. The difference in survival between these two groups is statistically significant (P = 0.01).
Flow cytometric determination of esterase and phosphatase activities and kinetics in hematopoietic cells with fluorogenic substrates
Authors: Malin‐Berdel J. , Valet G. 
Published: August 2005

AbstractViable and formaldehyde fixed rat bone marrow or spleen cells and rat or human blood leukocytes were incubated with fluorescein (fluorescein‐diacetate, ‐dibutyrate and ‐laurate) or umbelliferone (4‐methylumbelliferyl acetate and ‐phosphate) fluorogenic substrates for subsequent flow cytometric determination of cell fluorescence and cell volume. Formaldehyde‐fixed cells preserved between 14 and 20% of the enzyme activity of the unfixed cells and the number of cell clusters for fixed and unfixed cells was the same. The esterase substrates revealed one cell cluster for spleen cells, two for bone marrow cells and four for peripheral blood leukocytes. Phosphatase activity was only associated with a cell cluster of large cells. The time course of substrate cleavage was linear during the first 10 min of incubation. Later on a plateau was reached. Specific enzyme activities were calculated on a single cell level from the simultaneous cell volume and cell fluorescence measurement. Two enzyme activites could be measured simultaneously by using a substrate mixture of umbelliferone acetate and fluorescein acetate.
Preparation of tissues for DNA flow cytometric analysis
Authors: Thornthwaite Jerry T. , Sugarbaker Everett V. , Temple Wally J. 
Published: August 2005

AbstractA method for measuring DNA in tissue cells by flow cytometry utilizing a one step combination nuclear isolation‐DNA fluorochrome staining procedure is described. A variety of cells and tissues, both in vivo and in vitro, was used to illustrate the universal nature of this technique. These included murine bone marrow, liver testicle, sarcoma brain tumor, rat pancreatic islets, human peripheral blood, colon mucosa, colon cancer, sarcoma and brain tumor tissues. A special nuclear isolation medium, which contained either of the DNA fluorochromes, 4′,6‐diamidino‐2 phenylindole‐2 HCl or propidium iodide, was utilized successfully to isolate single suspensions of DNA fluorochrome stained nuclei in a rapid (5–10 min), consistent manner from a variety of tissues and cells. Multiple sampling of the same tissue or comparison between whole tissues and their single cell isolates showed that a representative sample was being obtained.
Nozzle design for the generation of plane liquid surfaces
Authors: Eisert Wolfgang G. , Dennenloehr Manfred 
Published: August 2005

AbstractMeasurements besides total fluorescence intensity of more elaborate optical techniques such as light scattering, extinction as well as fluorescence polarization and slit scan profiles have been reported in various cell sorter design studies. However the cylindrical liquid stream in air, common to many research system, limits the optical properties of the system. We report the successful application of three new types of nozzles, all having in common the fact that the main optical axes intersect plane liquid surfaces. This has been achieved on the basis of a double sheath arrangement, which we have reported previously. The nozzles generate fluid streams with either rectangular, square or triangular cross‐sections at the location of the optical axis. The latter facilitates the alignment of two beams with different wavelengths on the same optical axis within the liquid. Square or rectangular cross‐sections improve light scattering and extinction measurements and may well be better suited to more complicated geometrical analysis of cells and particles in flow streams.