Hongfeng Sun

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A method has been developed for the determination of methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) in human urine using microwave extraction-gas chromatography(GC). To improve the extraction efficiency, experimental parameters of the extraction, including extraction solvent and its amount, pH value of(More)
Peers were divided into different peer groups according to similar contents or interests to improve search efficiency in peer-to-peer networks. But with the number of peer groups grows up, when none peer could provide results for a request within one peer group, flooding will be used which will also cause large network flows. In order to increase search(More)
In P2P systems, peers are often organized by similarity, trying to ensure the content that any peer needs be found in peers who are in short connections with them to improve the efficiency of searching resources which become popular and difficult in P2P field. First, the background of P2P systems and typical applications are introduced. Then the concept of(More)
A method was developed for the determination of methamphetamine (MAM) in human blood using microwave extraction-gas chromatography (GC). To improve the extraction efficiency, experimental parameters on the extraction, including such as extraction solvent and its amount, pH value of blood sample, extraction time and temperature were investigated. Comparing(More)
This cross-sectional study aimed to investigate the relationship between glycosylated haemoglobin (HbA1c) and cognitive vulnerability to depression (dysfunctional attitudes) in patients with type 2 diabetes mellitus. A total of 245 valid records from June 2016 to December 2016 were collected from a hospital in Beijing. Participants were asked to complete(More)
In the modern social, with the enhancement of informatization degree of every industry, a great deal of complicated data were produced and accumulated. These big data will highlight the important value with the function of data mining technique. The paper discourses the five aspects in which data mining of big data serviced finance industry. This also(More)
We report a novel graphene oxide quantum dot (GOQD)-sensitized porous TiO2 microsphere for efficient photoelectric conversion. Electro-chemical analysis along with the Mott-Schottky equation reveals conductivity type and energy band structure of the two semiconductors. Based on their energy band structures, visible light-induced electrons can transfer from(More)