Publications by authors named "Chaoqun Geng"

We have developed an innovative optical emission spectrometry imaging device integrating a diode laser for sample introduction and an atmospheric pressure plasma based on dielectric barrier discharge for atomization and excitation. By optimizing the device parameters and ensuring appropriate leaf moisture, we achieved effective imaging with a lateral resolution as low as 50 μm. This device allows for tracking the accumulation of Cd and related species such as K, Zn, and O, in plant leaves exposed to different Cd levels and culture times.

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Objectives: Sarcomatoid renal pelvis carcinoma (SRPC) is a rare variant of RPC. We aimed to summarize the clinicopathological features and prognostic factors of SRPC.

Methods: In this retrospective study, we collected data from 24 patients with SRPC who were treated at the Department of Urology, Affiliated Hospital of Qingdao University between 2008 and 2021.

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Over the past decade, miniaturized optical emission spectrometry (OES) systems utilizing atmospheric pressure plasmas (APPs) as radiation sources have exhibited impressive capabilities in trace heavy metal analysis. As the core of the analytical system, APPs sources possess unique properties such as compact size, light weight, low energy requirement, ease of fabrication, and relatively low manufacturing cost. This critical review focuses on recent progress of APP-based OES systems employed for the determination of heavy metals.

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An infrared laser (808 nm) has been coupled with dielectric barrier discharge (DBD) for optical emission spectrometric determination of S and Cl in organic compounds. The use of a continuous wave IR laser with an output power of 1-2 W allows volatilization of analytes from condensed surfaces. Analytes thermally delivered to the gas phase are excited and atomized by the DBD plasma triggered by an alternating voltage of 10 kV at 25 kHz under atmospheric pressure.

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