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991.
《Physics letters. A》2020,384(2):126061
In this paper, we proposed an unidimensional continuous-variable quantum key distribution (CV-QKD) protocol with discrete modulation, which waives the necessity in one of the quadrature modulations and further simplified the implementation of the CV-QKD protocol. On the basis of the Heisenberg uncertainty relation, we analyze the boundary between the unphysical and physical region. Besides, we utilize a novel proof approach to achieve a lower bound valid of transmission distance. This scheme shows an available method to further simplified the implementation of the QKD. 相似文献
992.
993.
994.
采用溶胶-凝胶法制备了不同烧结温度的钙钛矿类锰氧化物La0.67Sr0.33MnO3样品。实验结果表明,在1573 K以上烧结的样品,晶粒出现异常长大,晶界效应明显。随着烧结温度的提高,磁化强度逐渐增大,但样品的居里温度基本不变。此外,在1173和1573 K温度下烧结的样品,均出现了低于居里温度的金属-半导体导电行为转变。在合适的烧结条件下,可以观察到隧道磁电阻(TMR)和超大磁电阻(CMR)2种磁电阻效应。实验表明,自旋电子的输运,不仅与样品平均粒径的大小和密度有关,而且与晶界的微观结构有密切关系。 相似文献
995.
Mustafa Yavuz 《高分子科学》2007,(4):347-355
Electrorheological (ER) properties of polyaniline (PAni), pumice and polyaniline/pumice composites (PAPC) were investigated. Polyaniline and PAni/pumice composite were prepared by oxidative polymerization. PAni/pumice particlesbased ER suspensions were prepared in silicone oil (SO), and their ER behavior was investigated as a function of shear rate, electric field strength, concentration and temperature. Sedimentation stabilities of suspensions were determined. It has been found that ER activity of all the suspensions increases with increasing electric field strength, concentration and decreasing shear rate. It has shown that the suspensions have a typical shear thinning non-Newtonian viscoelastic behavior. Yield stress of composite suspensions increased linearly with increasing applied electric field strength and with concentrations of the particles. The effect of high temperature on ER activity of purrfice/silicone oil systems was also investigated. 相似文献
996.
Sankar B Jaleel CA Manivannan P Kishorekumar A Somasundaram R Panneerselvam R 《Colloids and surfaces. B, Biointerfaces》2007,60(2):229-235
An investigation was carried out to find out the extent of changes occurred in groundnut (Arachis hypogaea L.) cultivars in response to paclobutrazol (PBZ) treatment under water deficit stress. Two groundnut cultivars namely ICG 221 and ICG 476 were used for the study. Individual treatment with PBZ and drought stress showed an increase in ascorbic acid, -tocopherol and reduced glutathione, superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) activities. PBZ with drought stressed plants maintained higher levels of antioxidant and scavenging enzymes. Significant differences were observed between cultivars and treatments. These results suggests that the adverse effects of water stress can be minimized by the application of PBZ by increasing the antioxidant levels and activities of scavenging enzymes such as SOD, APX and CAT. The Cv. ICG 221 appears to be more tolerant to water stress than the ICG 476. 相似文献
997.
Czesław Rudowicz Ireneusz Stefaniuk Roman Dziembaj Hitoshi Ohta Marcin Molenda Susumu Okubo Makoto Yoshida 《Research on Chemical Intermediates》2007,33(8):853-862
This paper deals with the analysis of the temperature dependence of high-frequency EMR (HF-EMR) spectra due to Mn3+ and Mn4+ ions in the lithium manganese spinel LiMn2O4. A range of powder samples obtained by the sol-gel method with calcinations in several temperature ranges were prepared for
this study. Based on the initial characterization carried out by a number of techniques, the physicochemical and structural
properties of the samples were earlier determined. Independently, temperature magnetization and HF-EMR measurements were carried
out. The EMR spectra vary strongly between samples, indicating possible structural or chemical changes. Quantitative analysis
of the temperature dependence of the HF-EMR spectra due to Mn3+ and Mn4+ ions in LiMn2O4 is presented in this paper. The spectral analysis concerns the line shape, linewidth, intensity and g-factors. Fittings using the Lorentzian spectral shape and, to a certain extent, the Gaussian spectral shape have been carried
out in order to parameterize the temperature dependence of the HF-EMR spectra. This parameterization of the HF-EMR experimental
data enables a deeper characterization of the samples. Subsequently, a better insight into the role of the Mn3+ and Mn4+ ions in accounting for the characteristics most suitable for application of LiMn2O4 as a cathode material may be gained. 相似文献
998.
999.
1000.
两亲嵌段共聚物溶液内胶束形成的温度效应 总被引:2,自引:0,他引:2
合成了一系列具有两亲嵌段结构的聚(乙二醇)(PEO)一聚(丙二醇)(PPO)共聚物.利用荧光探针及示差量热法测定了共聚物水溶液的临界胶束形成温度(CMT)值.发现二嵌段共聚物(PEO-PPO)和三嵌段共聚物(PEO-PPO-PEO)有着类似的变化规律,即随共聚物分子中疏水链(PPO)长度的增大,其CMT值降低.但三嵌段共聚(PPO-PEO-PPO)则因疏水链段处于共聚物分子的两端,因而在溶液中有可能形成立体网状交联结构.此外,利用探针分子在不同极性溶剂中荧光峰值波长发生位移的现象可以对形成胶束内核的组织程度、极性大小进行估测. 相似文献