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931.
V A Meshcheriakova M A Samsonov I A Frolova O A Plotnikova G R Pokrovskaia 《Voprosy pitaniia》1985,(3):9-13
A study was made of the effect of wheat bran contained by the antisclerotic diet on lipid metabolism in patients with chronic coronary heart disease. Eighty-two patients (males) aged 36-59 years with a history of myocardial infarction of 1- to 15 year-standing were entered into the study. It was ascertained that inclusion into the antisclerotic diet of wheat bran in an amount of 70-80 g does not exert any hypolipidemic action. No elevation of the serum alpha-cholesterol content was noticed either. The augmentation of the cholic acid concentration together with a reduction in the cholesterol content in the hepatic bile attests to its reduced lithogenicity. 相似文献
932.
R. Simarro S. Cervera-March S. Esplugas 《International Journal of Hydrogen Energy》1985,10(4):221-226
Water photolysis has been studied in liquid phase, using neutral aqueous suspensions of RuOx/Pt/TiO2 particles and u.v. light. A continuous gas flow apparatus of ca 350 cm3 of total volume and holding 150 cm3 of catalyst suspension was designed and tested. Hydrogen generation rates up to 110 μmol h?1 have been obtained. Influence of photoproducts and catalyst concentration on the process rate is studied. Discussion is centred in the role played by oxygen in catalyst activity and process dynamics. 相似文献
933.
V.R.S. Hutton 《Geothermics》1985,14(5-6)
The initial problems associated with the fieldwork and integration of the results of four independent European university research groups involved in magnetotelluric studies in the Travale Test Site are discussed. This is followed by an account of the development of collaborative field studies, rewarding data and computer programme interchange and finally compatibility in the resulting electrical conductivity models and their interpretation. A suggested strategy for future EEC collaborative geothermal studies concludes this overview. 相似文献
934.
SIMULATION OF THAWING OF FOODS USING FINITE ELEMENT METHOD 总被引:2,自引:0,他引:2
935.
936.
Bilateral control of teleoperators with time delay 总被引:5,自引:0,他引:5
A control law for teleoperators is presented which overcomes the instability caused by time delay. By using passivity and scattering theory, a criterion is developed which shows why existing bilateral control systems are unstable for certain environments, and why the proposed bilateral control law is stable for any environment and any time delay. The control law has been implemented on a single-axis force-reflecting hand controller, and preliminary results are shown. To keep the presentation clear, a single-degree-of-freedom (DOF) linear time-invariant (LTI) teleoperator system is discussed. Nevertheless, results can be extended, without loss of generality, to an n -DOF nonlinear teleoperation system 相似文献
937.
A monolithic grating surface-emitting, GaAs/AlGaAs, separate-confinement-heterostructure, single-quantum-well diode laser has been fabricated on a Si substrate using a single-step metalorganic chemical vapour deposition process. An output power of 30 mW has been obtained under pulsed operation with a peak emission wavelength of 885 nm.<> 相似文献
938.
Attar A. Nakhai M.R. Aghvami A.H. 《Wireless Communications, IEEE Transactions on》2008,7(4):1157-1162
In this paper, we propose a cognitive cellular system based on DS MC-CDMA to coexist with a number of narrow-band legacy systems in the same frequency range. If the bandwidth and the frequency location of each narrow-band system are known to this cognitive MC-CDMA, it is possible to mitigate their interfering effect in the cognitive receivers by adaptive transmission. We will develop an algorithm for calculating the adaptive transmission parameters and show that it combats interference in the channel effectively. 相似文献
939.
Koch B. Hidayat A. Hongbin Zhang Mirvoda V. Lichtinger M. Sandel D. Noe R. 《Photonics Technology Letters, IEEE》2008,20(12):961-963
We demonstrate endless polarization stabilization with a control speed of up to 9 krad/s, over random Poincare sphere trajectories. These are in total >35 Mrad long, are composed in particular of difficult-to-track circles with all radii and orientations, and thereby include all possible worst cases. The maximum polarization mismatch and relative intensity errors are 0.13 rad and 0.43%, respectively. The controller runs on a field-programmable gate array and uses a commercial multistage LiNbO3 polarization transformer as the control device. 相似文献
940.
Grobnic D. Mihailov S.J. Smelser C.W. Ramos R.T. 《Photonics Technology Letters, IEEE》2008,20(12):973-975
Strong fiber Bragg gratings were written through the standard polymer coatings of "off-the-shelf" high numerical aperture single-mode optical fibers after a few seconds exposure with femtosecond pulse durations of infrared radiation through a phase mask. While writing through the acrylate coating, we obtained index modulations of up to 1.4 x 10-3 and 7 x 10-4 with and without H2 -loading, respectively. 相似文献