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131.
Generalized procedures are discussed for the accurate calculation of thermodynamic properties of nonpolar and polar fluids and mixtures. It is shown that the concepts of van der Waals for simple fluids can be extended to complex substances, and that the properties of a wide range of fluids can be calculated from a sufficient number of macroscopic parameters defined through the vapor pressure. 相似文献
132.
The twist in carpet yarns of suitable construction can be adequately set by a continuous treatment with sodium bisulphite in a tape–scouring machine. Different levels of set can be produced by varying the conditions: increasing the bisulphite concentration, the pH of the solution, the dwell time, and the bath temperature all improve the set. Improvements in the colour of the yarn and changes in pH are produced. While the yarn strength and extensibility decrease, the changes are comparable with those produced by the autoclave and water–setting treatments examined. Adverse changes in carpet abrasion resistance may occur when concentrations in excess of 10g/l are used. Bisulphite setting has been found to be more suitable for yarns to be jet–printed than setting in an autoclave or by hot water. 相似文献
133.
Conditions were investigated to determine the optimum processing parameters for preparation of a protein isolate from the ground, dehulled lupin seeds of Lupinus angustifolius. The extraction variables were: particle size (16–100 mesh); pH (2–11); extraction medium; solvent to lupin ratio (10:1 to 40:1); temperature (20–60oC) and time (15–60 min). The isoelectric point of the lupin protein was found to be pH 4.5 with a protein solubility of greater than 90% above pH 8.0. Using 60–100 mesh ground lupin and extracting at pH 8.5 for 30 min, a protein isolate was obtained on acidification to pH 4.8 which was 89.4% protein compared to 34.0% protein for the original dehulled lupin. This protein isolate represented 19.8% of the starting material and 52% of the starting nitrogen. Similar results were also obtained when hexane defatted lupin was used. In this case the protein isolate had a protein content of 92.5%. The yield of protein isolate could be increased to 25.7% of the starting material if the extraction was repeated. The protein efficiency ratio for the protein isolate was 2.90 when supplemented with methionine. 相似文献
134.
This paper outlines a computer program especially tailored to the task of deriving explicit equations of motion for structures with point-connected substructures. The special purpose program is written in FORTRAN and is designed for performing the specific algebraic operations encountered in the derivation of explicit equations of motion. The derivation is by the Lagrangian approach. Using an orderly kinematical procedure and a discretization and/or truncation scheme, it is possible to write the kinetic and potential energy of each substructure in a compact vector-matrix form. Then, if each element of the matrices and vectors encountered in the kinetic and potential energy is a known algebraic expression, the computer program performs the necessary operations to evaluate the kinetic and potential energy of the system explicitly. Lagrange's equations for small motions about equilibrium can be deduced directly from the explicit form of the system kinetic and potential energy. 相似文献
135.
The purpose of this work is to examine the basic foundations, similarities and fundamental differences between the finite element methods (FEM) and the lumped parameter methods (LPM) of analysis for oceanic cables under hydrodynamic load conditions. The continuum method (CM) is presented as a ‘ground truth’ prior to presenting each aspect of the approximate method derivations. 相似文献
136.
137.
Leonard R. Worden 《Journal of the Institute of Brewing》1966,72(3):275-282
The Rigby-Bethune rapid methods for determining bitterness in beer are compared with Moltke-Meilgaard measurements. A new assay is presented which is suitable for the determination of bitterness in beers flavoured with isohumulone concentrates. 相似文献
138.
Michael?BosseEmail author Richard?Rikoski John?Leonard Seth?Teller 《The Visual computer》2003,19(6):417-430
This paper describes a system for structure from motion using vanishing points and three-dimensional lines extracted from omni-directional video sequences. To track lines, we use a novel dynamic programming approach to improve ambiguity resolution, and we use delayed states to aid in the initialization of landmarks. By reobserving vanishing points we get direct measurements of the robots three-dimensional attitude that are independent of its position. Using vanishing points simplifies the representation since parallel lines share the same direction states. We show the performance of the system in various indoor and outdoor environments and include comparisons with independent two-dimensional reference maps for each experiment . 相似文献
139.
A dynamical model for generating synthetic electrocardiogram signals 总被引:14,自引:0,他引:14
McSharry PE Clifford GD Tarassenko L Smith LA 《IEEE transactions on bio-medical engineering》2003,50(3):289-294
A dynamical model based on three coupled ordinary differential equations is introduced which is capable of generating realistic synthetic electrocardiogram (ECG) signals. The operator can specify the mean and standard deviation of the heart rate, the morphology of the PQRST cycle, and the power spectrum of the RR tachogram. In particular, both respiratory sinus arrhythmia at the high frequencies (HFs) and Mayer waves at the low frequencies (LFs) together with the LF/HF ratio are incorporated in the model. Much of the beat-to-beat variation in morphology and timing of the human ECG, including QT dispersion and R-peak amplitude modulation are shown to result. This model may be employed to assess biomedical signal processing techniques which are used to compute clinical statistics from the ECG. 相似文献
140.
McDonald LA Barbieri LR Carter GT Kruppa G Feng X Lotvin JA Siegel MM 《Analytical chemistry》2003,75(11):2730-2739
The molecular formulas for the structures and substructures of muraymycin antibiotics A1 (C52H90N14O19, MW 1214) and B1 (C49H83N11O18, MW 1113) were determined using electrospray ionization (ESI) Fourier transform mass spectrometry (FTMS). The muraymycin A1 and B1 structures were elucidated by utilizing capillary-skimmer fragmentation with up to five stages of mass spectrometry (MS5). Multi-CHEF, a multiple ion isolation method, was used at each stage of MS(n) to isolate a parent ion and up to four reference ions, for exact-mass calibration. The parent ions were fragmented by SORI-CID and the product ions internally calibrated with average absolute mass errors less than 1 ppm at each stage in the fragmentation processes. Using the top-down/bottom-up approach, the molecular formulas for the antibiotics were determined by summing the elemental formulas of the neutral losses, obtained by measuring the mass differences (<500 Da) between the genetically related sequential parent ion masses in the MS(n) spectra, with the unique elemental formula of the lowest parent ion mass (<500 Da). The structures of 12 additional compounds in the muraymycin complex were elucidated using HPLC ESI capillary-skimmer CID FTMS by correlating their fragmentation patterns with those of muraymycins A1 and B1. Sequential neutral losses of an aminosugar, a valine, a uridine, and an ester fatty acid from the muraymycin parent ions provided diagnostic fragments for characterization. 相似文献