Investigation of the filtration rate of silica in aluminum fluoride production from silicic acid

The effect of some influencing parameters such as temperature, initial concentration of flusilicic acid, rate of addition of Al(OH)₃ powder, agitation speed and aging time of slurry and their mixed effects on the filtration rate of silica precipitates have been investigated. Moreover, a suitable model is presented to describe the formation mechanism of aggregated silica precipitates which can well explain the effect of different factors on the filtration rate of the silica precipitates.     

Far infrared spectrum of CD3OH methanol from 40–220 CM−1

The Fourier transform far-infrared (FTFIR) spectrum of CD₃OH has been obtained from 40–220 cm^?1 at a resolution of 0.002 cm^?1, and partially analyzed. Numerousb-type branches have been assigned in the spectrum, ranging over torsional states fromn=0 to 3. The branches have been fitted toJ(J+1) power-series energy expansions in order to obtainJ-independent branch origins. These in turn have been fitted to the torsion-rotation Hamiltonian, and improved molecular constants have been obtained for the ground vibrational state.     

Total cavopulmonary anastomosis: selection criteria related to postoperative results

Cystitis cystica, a common urothelial pathology whose aetiology, morphology and clinical significance are poorly understood, affects the human urinary bladder and trigone in both sexes. We have studied the fine structure of urothelial cysts in 11 patients diagnosed cystoscopically as suffering from cystitis cystica. Several abnormal features were observed in the adjacent urothelium, including large intracellular vacuoles (4 patients), Brunn's nest (5), lymphocyte infiltration (10) and generally disorganised urothelial architecture (10). Squamous metaplasia was observed in one case. The wall of each cyst consisted of a 2-3 layered epithelium with either tall columnar or flattened cells lining the fluid-filled lumen. Both types of lining cell possessed short microvilli, while the columnar type also contained numerous membrane-bound, electron dense secretory granules in the apical cytoplasm. Rough endoplasmic reticulum, mitochondria and Golgi membranes were plentiful in the surface cells. Junctional complexes joined adjacent lining cells. The deeper cells contained relatively fewer organelles, while a basal lamina separated the cyst wall from the underlying connective tissue.     

Analysis of two loops for carrier recovery in CPM with index 1/2

An examination is made of the performance of a squaring loop and a fourth-power loop used for tracking the received carrier phase of binary continuous-phase modulated (CPM) signals with index 1/2. Noise-free analysis is performed first and a simple relationship between the phase error and the control voltage is obtained for each case, with the premodulation filter response as a parameter. Linearized analysis of the phase error variance is then conducted in the presence of additive white Gaussian noise. It is shown that the phase variance in both cases contains a self-noise component that sets a lower bound on the synchronizer's performance at very high signal-to-noise ratios. Numerical results are presented for a number of popular CPM signals. It is found that the squaring loop performs best with MSK (minimum shift keying), while the fourth-power loop performs best with duobinary MSK     

Isolation and characterization of a lectin with antifungal activity from Egyptian Pisum sativum seeds

A plant lectin isolated in its pure state from the Egyptian seeds of Pisum sativum (PSL) produced two bands in SDS–PAGE (5.53 and 19.3 kDa; i.e. α and β chain) but one peak by gel filtration chromatography on Sephadex G-100, corresponding to 50 kDa, i.e., a dimeric structure of two monomers, each consisting of one α and one β subunit. PSL is a glycoprotein bound with glucose (2 mol/mol of protein) and stabilized by 2 atoms of each of Ca²⁺ and Mn²⁺ per molecule of protein. It highly agglutinated human, rabbit and rat erythrocytes but weakly agglutinated chicken erythrocytes, while no agglutination occurred with sheep erythrocytes. Hemagglutination was markedly affected by acidic pH, but was heat stable below 60 °C for 30 min. Among the various tested sugars, PSL agglutination was most inhibited by mannose. PSL is rich in hydroxyl amino acids while totally lacking sulfur amino acids. PSL inhibited the growth of Aspergillus flavus, Trichoderma viride and Fusarium oxysporum.     

An "offshore-resistant" degree program

The new University of Guelph-Humber has created an innovative, combined university degree and college diploma program in computer science and communications technology. This venture between the university and the Humber Institute of Technology and advanced learning offers jointly an honors baccalaureate in computing science from Guelph and a diploma in wireless and telecommunications systems technology from Humber. The program, one of six joint programs between the two institutions, specializes in distributed and wireless computing.     

Controlled-Release Frusemide Microcapsules: Preformulation Studies

Microencapsulation of plain frusemide or its solid-dispersion with PEG 6000 was achieved by phase-separation coacervation. Formulations showed reasonable in-vitro dissolution behaviour were assessed for their absorption rates by LD₅₀ testing in mice. Toxicity studies showed close agreement between the increase in lethal dose and the decrease in dissolution rate and revealed that the formulation containing frusemide as fused mixture with PEG 6000 and microencapsulated with polystyrene, in frusemide-PEG 6000-polystyrene weight ratio of 2:2:1, was the formula of choice for prolonging the absorption, hence, the action of frusemide.     

Work flow methodology : A proposed approach for analysis and conceptual design of large scale computer based information systems

The objective of this paper is to explain our approach called “Work Flow Methodology for Analysis and Conceptual Data Base Design of Large Scale Computer Based Information System”. The user fills in, through the different steps of the methodology and in the light of the definition of dynamic adaptive system, a number of forms which relate the topological dimension to the time dimension for each application of a given system. In addition, we obtain the “Unit Subschema” which defines the responsibilities of issuing and authorization of receiving information at the proper time. Finally, we apply our methodology to the Registration System in Kuwait University.     

Modal analysis of open groove waveguide

A self-contained analysis for lower-order modes in the open groove waveguide is presented. By adopting an approximate form for the fields in the outer region of the guide and then performing the remainder of the analysis rigorously, closed-form results for the fields and modal equation are obtained. The analysis shows a simple transverse network representation that can be compared with that obtained by A.A. Oliner and P. Lampariello (ibid., vol.33, no.9, p.755-64, 1985). Universal dispersion curves, obtained numerically for the dominant mode, are presented