Chemical structure based model to predict nitrate radical‒mediated degradation of saturated organic contaminants in troposphere

Chemical structure-based predictive model for the oxidation of trace organic contaminants by sulfate radical

Water Research ◽

10.1016/j.watres.2017.03.015 ◽

2017 ◽

Vol 116 ◽

pp. 106-115 ◽

Cited By ~ 67

Author(s):

Tiantian Ye ◽

Zongsu Wei ◽

Richard Spinney ◽

Chong-Jian Tang ◽

Shuang Luo ◽

...

Keyword(s):

Predictive Model ◽

Organic Contaminants ◽

Chemical Structure ◽

Sulfate Radical ◽

Trace Organic Contaminants ◽

Trace Organic

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Changes of Chemical Structure and Composition of Charcoal by Radiocarbon Pretreatments: Decontamination by ABA and ABOx Treatments

Radiocarbon ◽

10.1017/rdc.2016.29 ◽

2016 ◽

Vol 58 (3) ◽

pp. 565-581 ◽

Cited By ~ 3

Author(s):

Shinji Tomiyama ◽

Masayo Minami ◽

Toshio Nakamura ◽

Koichi Mimura ◽

Hiroyuki Kagi

Keyword(s):

Organic Contaminants ◽

Environmental Samples ◽

Chemical Structure ◽

Oxidative Degradation ◽

Chemical Oxidation ◽

Molecular Structures ◽

Acid Base ◽

Oxidation Treatment ◽

Pine Wood ◽

Compositional Changes

AbstractCharcoal is widely used for radiocarbon dating in archaeological and paleoenvironmental studies. Reliable 14C dating requires appropriate chemical treatment to remove postdeposition contamination from the charcoal samples. This study assesses two pretreatments: acid-base-acid (ABA) and acid-base-oxidation with stepped combustion (ABOx-SC). In addition to 14C, the effects of the treatments on the chemical structure and composition of charcoal were studied using Fourier transform infrared spectroscopy (FTIR) and C/H/O elemental analysis. Samples of pine wood charred in the laboratory at 270, 300, 400, 500, and 600°C, and environmental samples of charred pine wood from pyroclastic flow deposits in southern Kyushu, Japan, were tested. The laboratory-charred samples showed that NaOH treatment removed highly hydrophilic organic components derived from endogenous and exogenous organic materials in the samples and that oxidation treatment caused the oxidative degradation of molecules in samples starting from its edges. The ABA-treated environmental charcoal yielded younger 14C dates than the ABOx-treated samples, probably owing to the effects of remaining organic contaminants bound to the edges of the aromatic molecular structures produced by the original pyrolysis. Meanwhile, it was found that ABA-SC treatment can reduce contaminants as effectively as ABOx-SC treatment. This implies that the stepped combustion (SC), not the chemical oxidation, is the key to reduce contaminant residue left after ABA and ABOx treatments. The results in this study indicate that the investigation of the structural and compositional changes of charcoal during its pretreatment is useful for assessment of the reliability of the 14C ages.

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Inelastic Electron-Matter Interactions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070047 ◽

1978 ◽

Vol 36 (3) ◽

pp. 259-267

Author(s):

J. Silcox

Keyword(s):

Electron Microscope ◽

Energy Loss ◽

Chemical Structure ◽

Inelastic Electron ◽

Primary Concern ◽

Unique Probe ◽

Introductory Paper ◽

Elastic Processes ◽

Experimental Level ◽

Inelastic Processes

In this introductory paper, my primary concern will be in identifying and outlining the various types of inelastic processes resulting from the interaction of electrons with matter. Elastic processes are understood reasonably well at the present experimental level and can be regarded as giving information on spatial arrangements. We need not consider them here. Inelastic processes do contain information of considerable value which reflect the electronic and chemical structure of the sample. In combination with the spatial resolution of the electron microscope, a unique probe of materials is finally emerging (Hillier 1943, Watanabe 1955, Castaing and Henri 1962, Crewe 1966, Wittry, Ferrier and Cosslett 1969, Isaacson and Johnson 1975, Egerton, Rossouw and Whelan 1976, Kokubo and Iwatsuki 1976, Colliex, Cosslett, Leapman and Trebbia 1977). We first review some scattering terminology by way of background and to identify some of the more interesting and significant features of energy loss electrons and then go on to discuss examples of studies of the type of phenomena encountered. Finally we will comment on some of the experimental factors encountered.

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Chemical structure of diamond-like carbon thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017668x ◽

1990 ◽

Vol 48 (4) ◽

pp. 710-711

Author(s):

N.-H. Cho ◽

K.M. Krishnan ◽

D.B. Bogy

Keyword(s):

Electrical Resistivity ◽

Chemical Structure ◽

Diamond Like Carbon ◽

Chemical Structures ◽

Sputtering Power ◽

Data Aquisition ◽

Equilibrium Phases ◽

Electron Energy Loss ◽

Power Densities ◽

Preparation Techniques

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.

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Relationship of Chemical Structure of Chlorpromazine to its Liver-Sensitizing Action

Gastroenterology ◽

10.1016/s0016-5085(19)35576-3 ◽

1958 ◽

Vol 35 (1) ◽

pp. 16-24 ◽

Cited By ~ 9

Author(s):

Harry Shay ◽

Herman Siplet

Keyword(s):

Chemical Structure ◽

Relationship Of

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Potential Uses of Vinegar as a Medicine and Related in vivo Mechanisms

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000440 ◽

2016 ◽

Vol 86 (3-4) ◽

pp. 127-151 ◽

Cited By ~ 3

Author(s):

Zeshan Ali ◽

Zhenbin Wang ◽

Rai Muhammad Amir ◽

Shoaib Younas ◽

Asif Wali ◽

...

Keyword(s):

Chemical Structure ◽

Review Paper ◽

Heart Diseases ◽

Folk Medicine ◽

Active Role ◽

Current Review ◽

Different Types ◽

Positive Effect

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.

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