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41.
The enzymic activity of the GTP-dependent acyl-CoA synthase isolated from rat liver mitochondria is affected by removal and
addition of lecithin (3). Purified preparations of this enzyme contain bound lecithin. In this presentation the nature of
the lecithin-protein interaction is examined. From binding measurements at different temperatures it is possible to postulate
which type of secondary valence bonds is holding the protein and lecithin together.
Presented at AOCS Meeting, Chicago, October 1967. 相似文献
42.
M. Rossi G. Vitali D. Karpuzov M. Kalitzova H. Budinov 《Journal of Materials Science》1991,26(12):3337-3342
GaAs 100 wafers were implanted and later annealed by using three different techniques: furnace thermal annealing (FTA), flash lamp (RTA) and low-power laser annealing (LPLA). The resulting modifications of the structure were studied by RHEED. The RHEED pattern analysis indicates that: (a) A well annealed structure is observed after thermal treatment in furnace at 850 °C for 30 min; (b) the particular RTA employed leads to some texturing, but is not sufficient to provide good structural effects; (c) best annealing under our conditions is obtained by the LPLA technique, especially for low ion doses (less than 1013 cm–2); (d) variable-glancing-angle RHEED is an effective and convenient method to investigate the ion induced disorder in crystals at small depths. 相似文献
43.
Marasca Andre Backes Andre Favarim Fabio Teixeira Marcelo Casanova Dalcimar 《国际自动化与计算杂志》2021,18(3):468-479
Machine Intelligence Research - The success of new scientific areas can be assessed by their potential for contributing to new theoretical approaches aligned with real-world applications. The... 相似文献
44.
Kaio C. S. Rodrigues Ivan I. K. Veloso Marcelo P. A. Ribeiro Antonio J. G. Cruz Alberto C. Badino 《加拿大化工杂志》2021,99(1):401-409
Fast, simple, accurate, and inexpensive methods for obtaining analyte concentration data are desirable in the industrial sector. In the present study, the use of Fourier transform mid‐infrared (FT‐MIR) spectroscopy, combined with partial least squares (PLS) regression, was investigated as a tool for real‐time monitoring of processes of ethanol absorption in glycols. Calibration was performed using simple synthetic samples containing ethanol, water, and monoethylene glycol (MEG) or diethylene glycol (DEG). The PLS models presented excellent performance, with correlation coefficients (R2) close to unity and root‐mean‐square errors of cross‐validation (RMSECV) and prediction (RMSEP) lower than 2% of the calibration data ranges for both analytes (ethanol and water) in both absorbents (MEG and DEG). The monitoring technique developed has potential to be applied in absorption processes and could also be used in other large‐scale unit operations, providing information in real time and enhancing process control. 相似文献
45.
G. J. Feng J. D. Rossi M. T. Gerusky 《Journal of Materials Engineering and Performance》1994,3(1):105-109
An attempt has been made to apply the linear elastic fracture mechanics concept to Beta-C titanium alloy pressure vessels
that exhibited brittle fractures during hydrotesting. Based on the results of stress analysis on the real structures and fracture
surface examinations, a stress-intensity factor,K
IC, was estimated. TheK
IC value of the material in the cracking direction was measured by a surface semi-elliptical crack method. It was found that
theK
IC value of the material is very close to the estimated stress-intensity factorK
I during failure, which places the pressure vessels in a critical condition in that a small variation in flaw size may cause
a catastrophic failure. A compromise must be made betweenK
IC and the required yield strength. In this restricted case, the yield strength of the material should be controlled in the
range of 1150 to 1200 MPa to avoid brittle fracture and the possible occurrence of yield during hydrotesting. Control of microstructure
and other mechanical properties is also discussed in this investigation. 相似文献
46.
This research focused on determining the sociocultural factors that build the social perception of the social roles of senior citizens in Chile in the 2002–2012 period. For this purpose, public opinion was studied in newspapers El Mercurio and La Cuarta. Specialized opinion included the Senior Citizen Program of Pontificia Universidad Católica de Chile, the National Service for Senior Citizens, the Social Observatory for Aging and Old Age of Universidad de Chile, and the Society of Geriatrics and Gerontology of Chile. A comprehensive methodology was used, along with a bibliographical four-stage design. The following ten sociocultural factors were identified: Health and Quality of Life, Studies and Data, Social Images of Aging, Gerontological Concepts and Sociopolitical Participation, Gerontological Policies, Plans and Principles, Aging, Production and Gender, Institutionalization, Demographic Growth, Gerontological Training, and Exclusion and Old Age. This work suggests modifying the conceptual premise that emphasizes the inexistence of a social role for elderly people with a vision centered on the heterogeneity of social roles under permanent sociocultural construction. 相似文献
47.
48.
49.
Felisari L Grillo V Jabeen F Rubini S Menozzi C Rossi F Martelli F 《Ultramicroscopy》2011,111(8):1018-1028
A dedicated specimen holder has been designed to perform low-voltage scanning transmission electron microscopy in dark field mode. Different test samples, namely InGaAs/GaAs quantum wells, InGaAs nanowires and thick InGaAs layers, have been analysed to test the reliability of the model based on the proportionality to the specimen mass-thickness, generally used for image intensity interpretation of scattering contrast processes. We found that size of the probe, absorption and channelling must be taken into account to give a quantitative interpretation of image intensity. We develop a simple procedure to evaluate the probe-size effect and to obtain a quantitative indication of the absorption coefficient. Possible artefacts induced by channelling are pointed out. With the developed procedure, the low voltage approach can be successfully applied for quantitative compositional analysis. The method is then applied to the estimation of the In content in the core of InGaAs/GaAs core-shell nanowires. 相似文献
50.
Jeanbourquin D Sage D Nguyen L Schaeli B Kayal S Barry DA Rossi L 《Water science and technology》2011,64(5):1108-1114
Discharges of combined sewer overflows (CSOs) and stormwater are recognized as an important source of environmental contamination. However, the harsh sewer environment and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. An in situ system for sewer water flow monitoring based on video images was evaluated. Algorithms to determine water velocities were developed based on image-processing techniques. The image-based water velocity algorithm identifies surface features and measures their positions with respect to real world coordinates. A web-based user interface and a three-tier system architecture enable remote configuration of the cameras and the image-processing algorithms in order to calculate automatically flow velocity on-line. Results of investigations conducted in a CSO are presented. The system was found to measure reliably water velocities, thereby providing the means to understand particular hydraulic behaviors. 相似文献