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991.
992.
The fatty acid profile and beta-carotene content of a number of Australian varieties of purslane (Portulaca oleracea) were determined by GC and HPLC. The total fatty acid content ranged from 1.5 to 2.5 mg/g of fresh mass in leaves, 0.6 to 0.9 mg/g in stems and 80 to 170 mg/g in seeds. alpha-Linolenic acid (C18:3omega3) accounted for around 60% and 40% of the total fatty acid content in leaves and seeds, respectively. Longer-chain omega-3 fatty acids were not detected. The beta-carotene content ranged from 22 to 30 mg/g fresh mass in leaves. These results indicate that Australian purslane varieties are a rich source of alpha-linolenic acid and beta-carotene. 相似文献
993.
Higher Order Squeezed States of Anharmonic Oscillators 总被引:1,自引:0,他引:1
Ji-Suo Wang Tang-Kun Liu Ming-Sheng Zhan 《International Journal of Theoretical Physics》2000,39(11):2583-2593
In this paper the N eigenstates of the Nth powers (N 3) of the annihilationoperator of an anharmonic oscillator are constructed and their completeness isinvestigated. We introduce a new kind of higher order squeezing, Mth-order SU(1,1) squeezing. The properties of Mth-order SU(1, 1) squeezing and anticorrelationof the N states are studied. The result show that these states may form a completeHilbert space; the Mth-order [M = (n + 1/2)N;n = 0,1, ...] SU(1, 1) squeezingeffects exist in all of the N states when N is even. There is anticorrelation in allof them. 相似文献
994.
本证明明了多线性Littlewood—Patey算子在一类H^1空间上的加权有界性。 相似文献
995.
Yuri Alexeev Theresa L. Windus Chang‐Guo Zhan David A. Dixon 《International journal of quantum chemistry》2005,104(3):379-380
The original article to which this Erratum refers was published in International Journal of Quantum Chemistry (2005) 102(5) 775–784 相似文献
996.
In this paper,we report on the magnetic properties of Fe3O4 nanoparticles with different grain sizes under different pressures.In all the samples,the saturated magnetization Ms shows a linear decrease with increasing pressure.The thickness of the magnetic dead layer on the nanoparticle surface nuder different pressures was roughly estimated,which also increases with increasing pressure.The transport measurements of the nanoparticle Fe3O4 compacts show that the low-field magnetoresistance (MR) value is insensitive to the grain size in a wide temperature range;however,the high-field MR value is dependent on grain size,especially at low temperatures.These experimental results can be attributed to the different surface states of the nanoparticles. 相似文献
997.
998.
介绍了二类不同结构的(表面和侧面发射型)红外发光二极管.研究和分析了它们在低频大电流脉冲注入下的Pp—Ip特性和直流注入下的光谱特性.结果表明:正常情况下,器件具有线性的Pp—Ip特性,直流注入下的发射光谱具有高斯分布形状,对于Burrus表面发射型器件,在0—3A的峰值脉冲电流注入下,部分器件具有的异常Pp—Ip特性:线性-亚线性-超线性区.在20—100mA的直流电流注入下,部分器件的发射光谱具有多峰状. 相似文献
999.
Rajendra Bhatia Xingzhi Zhan 《Proceedings of the American Mathematical Society》2001,129(8):2277-2281
Let be a compact operator on a Hilbert space such that the operators and are positive. Let be the singular values of and the eigenvalues of , all enumerated in decreasing order. We show that the sequence is majorised by . An important consequence is that, when is less than or equal to , and when this inequality is reversed.
1000.
An MHB amphiphile, N-stearoyl-l-glutamic acid (C(18)-Glu), forms disk- and fiber-like nanostructures respectively in hydrophilic and hydrophobic environments due to the inter- and intra-molecular H-bonds. 相似文献