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991.
In the development of a novel freeze-drying technique in a fluidized bed at atmospheric pressure, a parallel study was undertaken using a conventional vacuum equipment. Two kinetically distinct phases were observed during freeze drying of representative Pood samples:
(1) a period during which the rate of drying was constant and (2) a second period during which the drying rate sufferedcontinual reduction. This paper focused attention on the primary drying period which corresponded with the kinetics of sublimation of pure 相似文献
(1) a period during which the rate of drying was constant and (2) a second period during which the drying rate sufferedcontinual reduction. This paper focused attention on the primary drying period which corresponded with the kinetics of sublimation of pure 相似文献
992.
P.J. Campion 《Measurement》1985,3(3):121-124
Two complementary national laboratory accreditation schemes are run by the National Physical Laboratory (NPL) to provide official recognition of competent British laboratories and an assurance of quality to their customers. The first of these, the British Calibration Service (BCS), was set up in 1966 to accredit laboratories to calibrate instruments, gauges and reference materials. In 1981 the National Testing Laboratory Accreditation Scheme (NATLAS) was formed to extend the service to all kinds of testing. Both BCS and NATLAS form an integral part of the UK national measurement system and were combined to form the National Measurement Accreditation Service on 1 October 1985. 相似文献
993.
994.
Translated from Atomnaya Énergiya, Vol. 67, No. 2, pp. 111–113, August, 1989. 相似文献
995.
测定钠中杂质的手动阻塞计的研究 总被引:1,自引:1,他引:0
文章介绍了测定钠中杂质浓度的手动阻塞计的原理、装置和实验结果。为了减少测量误差,我们研究了影响准确测定阻塞温度的因素,并且找到了减少测量误差的办法。在同样的杂质饱和温度下,该阻塞计测得的高、低阻塞温度所对应的杂质浓度差是很接近的。对氧其差值为1.03ppm;对氢为0.0763ppm。 相似文献
996.
997.
998.
The effect of secondary scattering that is produced by the induced current in an infinitely long, finitely conducting wire over a plane, finitely conducting earth from an incident electromagnetic pulse is investigated. This is accomplished by finding the field of a Hertzian dipole over the earth and identifying the part that is due to secondary scattering. Frequency-domain results for the overall induced current require that certain infinite integrals be numerically evaluated. Fourier inversion to the time domain in turn requires the numerical evaluation of another infinite integral. When the results are compared to those obtained when secondary scattering is ignored, it is found that secondary scattering slightly increases the current for the case of broadside incidence and reduces it for the case of grazing incidence by as much as two orders of magnitude. Peak currents are much smaller than previously thought. These general results hold for all of the earth parameters that were used in the study 相似文献
999.
Mountfield K. Mitchell P. Lee J.-W. Demczyk B. Artman J. 《IEEE transactions on magnetics》1987,23(5):2037-2039
A sequence of Co78 Cr22 films, 500 nm in thickness, was prepared by deposition on glass in a modified Varian D.C. magnetron S-gun sputtering system. The substrate temperature during deposition, Ts , was fixed at various values with an upper limit of 300°C. Specimens were examined by VSM, TM, FMR and TEM. Ms rises significantly with increasing Ts , peaking at 200°C at 370 emu/cm3. The effective volume-averaged anisotropy drops for Ts >110°C from +1.6 KOe to progressively negative values (-4.3 KOe at 300°C). From FMR we find indications of the presence, in addition to the transition and bulk layers, of a highly negative anisotropy constituent (sim-11.5 KOe anisotropy field). This resonance appears at Ts values of 150°C and above. TEM plane and cross-section views taken on a Ts = 150°C specimen show islands composed of tilted columns within the bulk. For vertical recording, specimens prepared at Ts values between 50 and 100°C are recommended. On the other hand, for longitudinal recording applications, films prepared at Ts values above 250°C would seem to be appropriate. 相似文献
1000.
W Seilmeier H Wieser H D Belitz 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1987,185(6):487-489
Reduced glutenin is separated by gel permeation high-performance liquid chromatography into three major and five minor fractions, which significantly differ in their amino acid compositions. By reversed-phase high performance liquid chromatography, about 20 glutenin components are obtained. These can be classified into three groups according to their amino acid compositions: a hydrophilic group with relatively high values of Glx and Phe, a more hydrophobic group with a high content of Gly, and a strongly hydrophobic group with higher values of Val and Leu. Groups 1, 2 and 3 contain middle-, high- and low-molecular-weight (MMW-, HMW-, LMW-) subunits respectively. 相似文献