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Abstract  

One novel styrylpyridine derivatives(AV-45) coupled with 99mTc complex was synthesized. 99mTc-BAT-AV-45 was prepared by a ligand exchange reaction employing sodium glucoheptonate, and effects of the amount of ligand, stannous chloride, sodium glucoheptonate and pH value of reaction mixture on the radiolabeling yield were studied in details. Quality control was performed by thin layer chromatography and high performance liquid chromatography. Besides the stability, partition coefficient and electrophoresis of 99mTc-BAT-AV-45 were also investigated. The results showed that the average radiolabeling yield was (95 ± 1%) and 99mTc-BAT-AV-45 with suitable lipophilicity was stable and uncharged at physiological pH.

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The essential oil extracted from Nardostachys chinensis Batal (NCB) was analyzed by gas chromatography-mass spectrometry (GC-MS) combined with two chemometric resolution methods (CRM), heuristic evolving latent projections (HELP), and selective ion analysis (SIA). Qualitative analysis was performed by comparing the obtained pure mass spectra with those in National Institute of Standards and Technology (NIST) mass spectra database. Identification of some compounds was assisted by comparison of programmed temperature retention indices (PTRIs). The quantitative results were obtained by overall volume integration (OVI). A total of 69 compounds in the essential oil of N. chinensis Batal were identified, accounting for 93.98% of the total content. The major compounds were (−)-spathulenol, epiglobulol, trans-longipinocarveol, and patchouli alcohol which contribute to the antimicrobial and antioxidant activity. The results showed that the efficiency and reliability were greatly improved by use of chemometric techniques and programmed temperature retention index as assistants of GC-MS in identification of the plant essential oil.

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Abstract

A methodology that may be applied to help in the choice of a continuous reactor is proposed. In this methodology, the chemistry is first described through the use of eight simple criteria (rate, thermicity, deactivation, solubility, conversion, selectivity, viscosity, and catalyst). Then, each reactor type is also analyzed from their capability to answer each of these criteria. A final score is presented using “spider diagrams.” Lower surfaces indicate the best reactor choice. The methodology is exemplified with a model substrate nitrobenzene and a target pharmaceutical intermediate, N-methyl-4-nitrobenzenemethanesulphonamide, and for three different continuous reactors, i.e., stirred tank, fixed bed, and an advanced microstructured reactor. Comparison with the traditional batch reactor is also provided.

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The thermal stability of chromium(III) complexes with dithiocarbamate acid derivatives was studied. The general formula of these complexes is (RCS2)3Cr where: The thermal stability of these complexes was found to depend on the kind ofR and the decomposition occur in several stages.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Ely, K. Anderson, D. Bates, R. Kouzes, C. Lo Presti, R. Runkle, E. Siciliano, and D. Weier

Abstract  

Plastic scintillator material is often used for gamma-ray detection in many applications due to its relatively good sensitivity and cost-effectiveness compared to other detection materials. However, due to the dominant Compton scattering interaction mechanism, full energy peaks are not observed in plastic scintillator spectra and isotopic identification is impossible. Typically plastic scintillator detectors are solely gross count detectors. In some safeguards and security applications, such as radiation portal monitors for vehicle screening, naturally-occurring radioactive material (NORM) often triggers radiation alarms and results in innocent or nuisance alarms. The limited energy information from plastic scintillator material can be used to discriminate the NORM from targeted materials and reduce the nuisance alarm rate. An overview of the utilization of the energy information from plastic scintillator material will be presented, with emphasis on the detection capabilities and potential limitations for safeguards and security applications.

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Thermal stability of stercorite H(NH4)Na(PO4)·4H2O

A cave mineral from Petrogale Cave, Madura, Eucla, Western Australia

Journal of Thermal Analysis and Calorimetry
Authors: Ray L. Frost and Sara J. Palmer

calcite with bat guano or with chemicals from bat guano which are water soluble and crystallise out on the calcite surfaces. The mineral stercorite is water soluble and may translocate through the Petrogale cave network [ 3 ]. Thermal analysis

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issue of whether this mineral would be stable if cave temperatures were significantly high. The mineral is a mixed anion sulphate phosphate of calcium and is formed by the reaction of bat guano with calcite. The mineral is monoclinic of point group m

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Thermal stability of crandallite CaAl3(PO4)2(OH)5·(H2O)

A ‘Cave’ mineral from the Jenolan Caves

Journal of Thermal Analysis and Calorimetry
Authors: Ray L. Frost, Sara J. Palmer, and Ross E. Pogson

are very old around 340 million years [ 10 ]. The calcite in the caves is older and has been dated as 430 million years old. The mineral crandallite is a hydroxy phosphate of calcium and aluminium. The mineral may be formed through the reaction of bat

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