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71.
The possible hypocholesterolaemic properties of milk and fermented milk products have been investigated in groups of albino rats given a basal diet, basal diet plus cholesterol, and basal diet plus cholesterol together with whole milk or standard or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey or lactose-hydrolysed condensed whey. After 30 d, triacylglycerols, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol. In general, yogurts changed HDL-cholesterol little, but tended to raise triacylglycerols. There was marked lowering of LDL-cholesterol in rats given either type of yogurt fortified with whey proteins. This study has demonstrated in a rat model that bifidus yogurts and yogurts fortified with whey proteins can reduce total and LDL-cholesterol, and suggests that if they have the same effect in human subjects they have potential value in cholesterol-lowering diets. 相似文献
72.
首先建立缺陷空间分布和粒径分布的模型,并讨论了缺陷通过版图产生电路错误的过程,给出了IC功能成品率模拟器XD-YES的实现。用XD-YES对微电子测试图和实际IC的功能成品率模拟和分析表明,其结果与实际符合很好,从而表明XD-YES的可行性和实用性。 相似文献
73.
It has been shown that coherent optical fiber receivers with a two-filter structure (TFS) consisting of a wide-band IF filter and a narrow-band postdetection filter are less susceptible to the influence of phase noise. However, the expanded IF bandwidth required to achieve optimum sensitivity performance is large, particularly in multichannel FSK systems. Forward error control coding can relax the laser linewidth requirement and improve receiver sensitivity. In this paper a multichannel asynchronous FSK scheme equipped with (31, k) Reed-Solomon codes is used to verify the coding benefit. A systematic error probability analysis is developed and a stable and accurate performance evaluation procedure is provided. The sensitivity penalties due to the combined phase noise and interchannel crosstalk for both coded and uncoded systems are calculated for comparison. The results show that the performance reduction due to phase noise can be largely alleviated by choosing a proper code rate and an optimum value of the expanded IF bandwidth 相似文献
74.
The electrochemical properties of an electrochemical double-layer capacitor electrode based on an ultra-long (500 μm), aligned, carbon nanotube array (ACNTA) in Et4NPF6/propylene carbonate electrolyte are examined. The specific capacitance of the ACNTA electrode in an organic electrolyte is 24.5 F g−1, which is larger than that obtained in an aqueous electrolyte. The results of ac impedance measurements show that the ACNTA electrode gives a high power density and an excellent rate capability in an organic electrolyte. It is shown that the ACNTA electrode has a lower equivalent series resistance and a better rate capability than activated carbon electrode. This is due to the fact that ACNTA possesses a larger pore size and a more a regular pore structure. Both these features are conformed by scanning electron microscopic and nitrogen gas adsorption studies. 相似文献
75.
针对750m^3高炉铁水生产富余状况,制订了富余铁水向铸铁机铸铁的调送方案,通过创新思维、系统挖潜、优化资源配置等措施的实施,保证了750m^3高炉的正常生产,取得了良好效果。 相似文献
76.
Efficient encoding of IEEE 802.11n LDPC codes 总被引:1,自引:0,他引:1
Addressed is the issue of LDPC coding for the emerging IEEE 802.11n standard. An efficient encoding algorithm is proposed. The algorithm is simple and easy to implement. The memory requirement is trivial 相似文献
77.
78.
Gallop J.C. Langham C.D. Ling Hao Abbas F. 《IEEE transactions on instrumentation and measurement》1997,46(2):122-125
High-quality, high-temperature superconducting (HTS) thin-films exhibit very low losses at microwave frequencies and, as a result, allow very high Q resonators to be produced. The size of such resonators may be significantly reduced by loading with low-loss single crystal dielectric. The potential for HTS dielectric loaded resonators as practical frequency standards and reference elements for low-phase-noise oscillators is assessed, with emphasis on operation at 60 K, a temperature readily attainable with compact Stirling cycle coolers 相似文献
79.
Trintinalia L.C. Bhalla R. Hao Ling 《Antennas and Propagation, IEEE Transactions on》1997,45(11):1664-1668
We present a scattering center extraction algorithm to parameterize the backscattered data from complex targets collected over large angular apertures. This parameterization is based on a scattering center model of the target, but includes an aspect-dependent amplitude function for each scattering center. A two-dimensional (2-D) adaptive Gaussian representation (AGR) algorithm is used to extract the position and the amplitude function associated with each scattering center. The algorithm is tested with data generated by the Xpatch radar simulation code as well as chamber measurement data. The results show that a very good compression ratio can be achieved, resulting in a compact scattering center model of the target. Once such model is available, we can easily reconstruct range profiles and ISAR images at any aspect on the same plane with good accuracy 相似文献
80.
微波在免疫组织化学中的应用 总被引:1,自引:0,他引:1
本文综述微波技术在免疫组织化学中的应用两头及其进展,着重介绍了微波在组织固定、抗原恢复和免疫染色方面的应用,并对微波免疫组织化学的应用前景进行了展望 。 相似文献