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Zeng L.,Xiangtan University | Xiao Y.,Changde Vocational Technical College | Liu J.,Xiangtan University | Tan L.,Xiangtan University
Journal of Molecular Structure | Year: 2012

Three new ruthenium(II) complexes, [Ru(MeIm)4phen]2+ (1), [Ru(MeIm)4ip]2+ (2) and [Ru(MeIm)4pip] 2+ (3), have been synthesized and characterized. The binding properties of the three complexes towards calf-thymus DNA were investigated by different spectrophotometric methods and viscosity measurements. In addition, the cytotoxicity of these complexes has been evaluated by MTT method and Giemsa staining experiment. The main results reveal that the plane area and hydrophobicity of intercalative ligands have a significant effect on the DNA-binding behaviors and the IC50 value of complex 2 against MCF-7 cells is close to that of cis-Pt(NH3)2Cl2. © 2012 Elsevier B.V. All rights reserved.

Qiao N.,University of Science and Arts of Iran | Tang J.,Changde Vocational Technical College
Advanced Materials Research | Year: 2012

Aiming at the dark printed circuit board photoelectric image that contains noise acquired by CCD system, the edge detection method by using multi-scale wavelet transform is proposed. Firstly, ts basic principle is analyzed in detail, and the simple physics explanation and formula deduction are given. Secondly, the idiographic detection steps are given. Finally, the results of experiment verify the correctness of theory analysis. © (2012) Trans Tech Publications, Switzerland.

Luo Y.L.,Changde Vocational Technical College
Applied Mechanics and Materials | Year: 2014

Aimed at the quality issues of current network streaming media playing, it manages by introducing a streaming media caching mechanism to help improve the playing effect. But the cached playing also has its own deficiencies, so here combines the adaptive control algorithm with the caching mechanism to solve this problem. It firstly introduces the streaming media service, and analyzes the transmission process of streaming media and adaptive media playing in detail; secondly analyzes the adaptive control algorithm of streaming media caching from the principle and design of reserving cache algorithm and the balance frame dropping algorithm; and finally gives the core code of the algorithm. This paper has a certain reference value to the video website developers and computer system architecture researchers. © (2014) Trans Tech Publications, Switzerland.

Luo Y.L.,Changde Vocational Technical College
Applied Mechanics and Materials | Year: 2014

With the development of society, urban traffic problem attracts more and more attention from people. In view of the current traffic worsening, it hopes to effectively shunt the travelers by the urban traffic navigation system, to ease traffic pressure. This article first analyzes the genetic algorithm in detail, and describes its principle and implementation steps; then specifically analyzes the overall design and design principle of the urban traffic navigation system; and at last gives part of the core code of the system. This paper has a positive effect for the software developer and city traffic management personnel. © (2014) Trans Tech Publications, Switzerland.

Zhang M.-M.,Hunan University | Zhang M.-M.,Changde Vocational Technical College | Gong J.,Changde Vocational Technical College | Song R.-J.,Hunan University | Li J.-H.,Hunan University
European Journal of Organic Chemistry | Year: 2014

Alkynes serve as prevalent intermediates in the synthesis of natural products and pharmaceuticals. We here described a new and efficient route to internal alkynes by Pd-catalyzed Kumada cross-coupling reactions of alkynyl halides with Grignard reagents. In the presence of Pd(PPh3)4 and N 1,N 1,N 2,N 2-tetramethylethane-1,2-diamine (TMEDA), a variety of alkynyl halides underwent Kumada coupling with Grignard reagents, giving the corresponding internal alkynes in moderate to good yields. A new Pd-catalyzed Kumada cross-coupling reaction of alkynyl halides with Grignard reagents has been developed. This transformation provides a new, experimentally simple access to internal alkynes in good yields, and it can accommodate a broad range of substrates with excellent functional group tolerance and good levels of selectivity control. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lv Y.-W.,Quzhou College | Hu W.,Quzhou College | Wang Y.-L.,Quzhou College | Huang L.-F.,Quzhou College | And 2 more authors.
Molecules | Year: 2011

A method for the analysis of flavonoids in Astragali Radix by highperformance liquid chromatography (HPLC) combined with photodiode-array detection (DAD) and an electrospray ionization (ESI) - mass spectrometry (MS) was developed. After the samples were extracted with ethanol, the optimum separation conditions for these analytes were achieved using a gradient elution system and a 2.0 × 150 mm Shimadzu VP-ODS column. Eight flavonoids were identified to exist in Astragali Radix based on their characteristic UV data and mass spectra. The concentrations of three major components in this herb-ononin, calycosin and formononetin-were determined by LC/ESI-MS in positive selective ion monitoring (SIM) mode. The calibration curves were linear in the range of 0.9̃180.0 μg.mL-1 for ononin, 1.8̃360.0 μg.mL -1 for calycosin and 1.4̃280 μg.mL-1 for formononetin, respectively. The limits of quantification (LOQ) and detection (LOD) were 0.9 μg. mL-1 and 0.2 μg mL-1 for ononin, 1.8 μg mL-1 and 0.5 μg.mL-1 for calycosin, 1.4 μg mL-1 and 0.5 μg.mL-1 for formononetin, respectively. The standard recoveries were between 95.4̃104.7%. The developed method was proven to be useful for the quantitative and qualitative analysis of flavonoid constituents in various resources of Astragali Radix. © 2011.

Zheng Y.,Changde Vocational Technical College
Applied Mechanics and Materials | Year: 2014

This paper establishes a set wireless intelligent vehicle monitoring system can be used in car based on S3C2440 and UC-OS, including hardware design, software design, system terminal high-speed wireless data transmission and monitoring platform. The experimental results show that the system have high detection sensitivity and high accuracy, and that can effectively prevent drunk driving and theft has very good practical value. © (2014) Trans Tech Publications, Switzerland.

Jieli L.,Changde Vocational Technical College
WIT Transactions on Information and Communication Technologies | Year: 2014

Some defects in the Visual FoxPro itself lead to its low safety performance and not powerful function. To make up the defects, and to play better the advantages of the database management and programming aspects, the system clarifies the operational application of the ACCESS database under the environment of Visual FoxPro. This article first details the comparison of the similarities and differences between Visual FoxPro and ACCESS, and then describes the main problems occurring in the ACCESS database operation in a Visual FoxPro environment, and finally focuses on the implementation methods of ACCESS database operations on the Visual FoxPro environment. © 2014 WIT Press.

Li H.-C.,Changde Vocational Technical College
Chinese Journal of New Drugs | Year: 2011

Objective: To optimize the process conditions of terbutaline sulphate dry powder inhalation by orthogonal design. Methods: Terbutaline sulphate dry powder inhalation was prepared by spray-drying method. Following spray-drying, resultant powders were characterized using scanning electron microscopy. Particle size analysis was performed by laser diffraction. Moisture content was examined by thermogravimetric analysis. And the aerosolisation performance was determined using twin-stage liquid impinger. The process conditions were optimized with orthogonal design combined with multi-index test. The powder yield , moisture content, aerodynamic diameter and respirable fraction were used as indices for orthogonal design. Results: The results of optimized process parameters were confirmed with atomization pressure of 190 kPa, aspiration speed of 0.7 m3·min-1, feed flow rate of 7 mL·min-1 and inlet temperature of 120°C. Conclusions: 50.54% yield, 0.467% moisture content, 1.80 μm aerodynamic diameter and 55.19% respirable fraction are obtained by the optimal process conditions. Orthogonal design combined with multi-index test can be used to optimize the preparation technique for terbutaline sulphate dry powder inhalation.

PubMed | Changde Vocational Technical College, Hunan Normal University, Lanzhou University, University of North Carolina at Chapel Hill and Beijing Kein Research Center for Natural science
Type: Journal Article | Journal: The journal of physical chemistry. A | Year: 2016

How to accurately predict electronic properties of a Columbic system with the electron density obtained from experiments such as X-ray crystallography is still an unresolved problem. The information-theoretic approach recently developed in the framework of density functional reactivity theory is one of the efforts to address the issue. In this work, using 27 atoms and 41 molecules as illustrative examples, we present a study to demonstrate that one is able to satisfactorily describe such electronic properties as the total energy and its components with information-theoretic quantities like Shannon entropy, Fisher information, Ghosh-Berkowitz-Parr entropy, and Onicescu information energy. Closely related to the earlier attempt of expanding density functionals using simple homogeneous functionals, this work not only confirms Nagys proof that Shannon entropy alone should contain all the information needed to adequately describe an electronic system but also provides a feasible pathway to map the relationship between the experimentally available electron density and various electronic properties for Columbic systems such as atoms and molecules. Extensions to other electronic properties are straightforward.

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