A large number of chemical, bio-chemical and pollution-control processes use heterogeneous fixed-bed reactors. The use of finite hollow cylindrical catalyst pellets can enhance conversion levels in such reactors. The absence of the pellet core can significantly lower the diffusional resistance associated with the solid phase. This leads to a better utilization of the catalytic material, which i...

Combination of solid-phase microextraction with gas chromatography enables rapid, repeated analysis of organic compounds in water. Fluazifop-p-butyl (FPB) (propanoic acid 2-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy] butyl ester) is the active substance in the herbicide Fusilade. Samples of distilled water were spiked with FPB in the laboratory and the analyte was isolated from the water ...

A rapid, specific and sensitive ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method was developed for the simultaneous determination of four trace alkaloids, including aconitine (AC), hypaconitine (HA), mesaconitine (MA) and yunaconitine (YA) in human urine samples. UPLC-MS-MS system coupled with an electrospray ionization (ESI) source was performed in multiple reactio...

We demonstrate a 158 fs 5.3 nJ mode-locked laser system based on a fiber oscillator, fiber amplifier and fiber compressor. Dispersion compensation in the fiber oscillator was obtained with a solid-core photonic bandgap (SC-PBG) fiber spliced to standard fibers, and external compression is obtained with a hollow-core photonic bandgap (HC-PBG) fiber.

in this project, eggshell membrane was used as a solid phase extraction sorbent for extraction of morphine followed by hplc analysis. at first, raw eggshell membrane was used and then, because of low adsorption of morphine on untreated eggshell membrane (

We develop a method for the fabrication of functional microstructured optical fibers (MOFs) by selectively filling the air holes with liquid phase materials, where we utilize the dependence of filling speed on the size of the air holes. As a demonstration, we construct a hybrid MOF by filling the center hollow core of a triangular lattice photonic crystal fiber with dye-doped curable polymer, a...

This application presents a fast, easy, and cost-effective method for the determination of 24 pesticide residues in red wine. Sample preparation involves the extraction of pesticides from red wine using the QuEChERS extraction method (AOAC version). The samples then undergo cleanup by dispersive solid-phase extraction (dSPE) using primary secondary amine (PSA) sorbent, which effectively retains...

In this paper, the possibility of using a new ordered nanoporous carbon as a new fiber in headspace solid phase microextraction (HS-SPME) to determine of mononitrotoluenes (MNTs) in waste water is demonstrated. The structural order and textural properties of the ordered nanoporous carbon were studied by X Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) images and nitrogen adsorpti...