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991.
Raman spectroscopy has been widely used to identify the physical properties of carbon nanotubes (CNTs), and to assess their func-tionalization as well as orientation. Recently, Raman spectroscopy has become a powerful tool to characterize the interfacial properties between CNTs and polymer matrices. This review provides an overview of micro-Raman spectroscopy of CNTs and its application in studying CNT reinforced polymer composites. Based on the specific Raman band shifts relating to the mechanical deformation of CNTs, Raman scattering can be used to evaluate the interactions between the CNTs and the surrounding polymer in the composites, and to detect the phase transitions of the polymer, and investigate the local stress state as well as the Young’s modulus of the CNTs. Moreover, we also review the current progress of Raman spectroscopy in various CNT macroarchitectures (such as films, fibers as well as composite fibers). The microscale structural deformation of CNT macroarchitectures and strain transfer factors from macroscale architectures to microscale structures are inferred. Based on an in situ Raman-tensile test, we further predict the Young’s modulus of the CNT macroarchitectures and reveal the dominating factors affecting the mechanical performances of the CNT macroarchitectures 相似文献
992.
In this paper, based on the verifiable pair and identity-based threshold cryptography, a novel identity-based (ID-based) threshold
decryption scheme (IDTDS) is proposed, which is provably secure against adaptive chosen ciphertext attack under the computational
bilinear Diffie-Hellman (CBDH) problem assumption in the random oracle. The pubic checkability of ciphertext in the IDTDS
is given by simply creating a signed ElGamal encryption instead of a noninteractive zero-knowledge proof. Furthermore, we
introduce a modified verifiable pairing to ensure all decryption shares are consistent. Our scheme is more efficient in verification
than the schemes considered previously. 相似文献
993.
Lianru Zhang Junjie Chen Siyang Song Zhonghui Zheng Yaojian Huang 《武汉大学学报:自然科学英文版》2010,15(5):444-448
The interaction between acetylgliotoxin and human serum albumin (HSA) has been studied by spectroscopic method. Acetylgliotoxin
quenches the intrinsic fluorescence of HSA in a static quenching procedure. The binding of acetylgliotoxin to HSA causes a
slight conformational change of HSA. The binding constants at different temperatures as well as enthalpy change and entropy
change, are calculated according to relevant fluorescent data and Van’t Hoff equation. The hydrogen bond is a predominant
intermolecular force for stabilizing the complex, which is in conformity with the results of molecular modeling study. 相似文献
994.
In this paper,a Littlewood-Paley function characterization of the spaces L p(R),1
相似文献
995.
For the problem of track correlation failure under the influence of sensor system deviation in wireless sensor networks, a
new track correlation method which is based on relative positional relation chart matching is proposed. This method approximately
simulates the track correlation determination process using artificial data, and integrally matches the relative position
relation between multiple targets in the common measuring space of various sensors in order to fulfill the purpose of multi-target
track correlation. The simulation results show that this method has high correlation accuracy and robustness. 相似文献
996.
A slight halophilic heterotrophic nitrobacteria named gs1 was separated from the matured activated sludge. According to the morphological observation,physiological biochemical tests and sequence analysis of the 16S rDNA,strain gs1 was identified to be as Pseudomonas sp. Sodium acetate and ammonium chloride were used as carbon and nitrogen sources,respectively,to investi-gate the characteristics of the bacterium. When cultured for 24 h under aerobic conditions,with the removal rates of the NH4+-N and COD being 82.2% and 74.73%,respectively,strain gs1 will have a nitrification function of producing NO2--N. When cultured for 24 h under aerobic conditions in nitrite medium,the removal rate of the NO2--N became 100%,and when cultured for 24 h under aerobic conditions in nitrate medium,the removal rate of the NO3--N became 97%. The result shows that this strain functions for either nitrification or denitrification,i.e.,it can complete the full process of biological deoxidation. 相似文献
997.
A method of sequence-based typing (SBT) has been adopted to assort types of exons 2 and 3, which have the most polymorphism,
of HLA-B locus of the Tujia nation group in Hubei province. The correlation among the HLA-B alleles, human papillomavirus
(HPV) infection and cervical cancer risk has also been investigated. Under the condition of resident location and age, race
unified, 100 specimens of cancer patients were sampled as a case group, of which 86 were HPV positive and were screened for
HLA-B alleles; while 187 specimens were taken from healthy people, of which 92 were HPV negative as a control group. The result
shows that by comparing the above mentioned 86 HPV positive cervical cancer group and 92 HPV negative normal group, it was
concluded that HLA-B*6701 was only found in the cervical cancer group (p < 0.034), which shows that HLA-B*6701 can be used as an important candidate biological marking gene for generation of cervical
cancer in Wufeng county of Hubei province. 相似文献
998.
We study the functions with low differential uniformity, and concentrates mainly on the properties of perfect nonlinear (PN)
functions, including the properties of the derivative of the components of those functions. Some sufficient and necessary
conditions have been explored to judge when a function is a PN function. These conditions may be useful in constructing new
PN functions. We also construct some functions with differential 4-uniformity that have rarely been studied in the literature.
Some of the constructed functions with differential 4-uniformity have high nonlinearity as well. Finally, a class of functions
with differential 4-uniformity which are not extended affine equivalent to any power functions are constructed. 相似文献
999.
A Kleene-Stone algebra is a bounded distributive lattice with two unary operations that make it a Kleene and a Stone algebra. In this paper, we study the properties of the prime ideals in a Kleene-Stone algebra and characterize the class of Kleene-Stone algebras that are congruence permutable by means of the dual space of a Kleene-Stone algebra and then show that a finite Kleene-Stone algebra is congruence permutable if and only if it is isomorphic to a direct product of finitely many simple algebras. 相似文献
1000.
So far, most of the proposed group key exchange (GKE) protocols do not consider the attack when the adversary reveals the parties’ephemeral private keys without their long-term private keys, so these GKE protocols are insecure on this attack. In this paper, for resisting above attack, we propose a dynamic authenticated group key exchange (AGKE) protocol in the ID-based setting. Different from previous ID-based protocols, our protocol does not utilize bilinear pairings, which makes it more efficient. At last, we analyze the security of the protocol in the eCK (enhanced Canetti-Krawczyk) security model. 相似文献