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31.
A mordenite-containing rock from the Tokaj-mountains was investigated. The effect of the treatment with hydrochloric acid solutions of various molarity was established. From gas adsorption measurements, scanning electron microscopic investigations and measurements with a mercury porosimeter conclusions were drawn on the changes caused by acid treatment. Slight changes in the texture were found, but no damage in the crystal structure could be observed.
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align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1087.gif" alt="pcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1084.gif" alt="mcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1095.gif" alt="chcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1093.gif" alt="khcy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1076.gif" alt="dcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1093.gif" alt="khcy" align="BASELINE" BORDER="0">, ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1076.gif" alt="dcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1074.gif" alt="vcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1074.gif" alt="vcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1076.gif" alt="dcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1084.gif" alt="mcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1103.gif" alt="yacy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1093.gif" alt="khcy" align="BASELINE" BORDER="0">, ntent/m818hh34v802h218/xxlarge1074.gif" alt="vcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1074.gif" alt="vcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1093.gif" alt="khcy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1081.gif" alt="jcy" align="MIDDLE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1081.gif" alt="jcy" align="MIDDLE" BORDER="0">. ntent/m818hh34v802h218/xxlarge1053.gif" alt="Ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1102.gif" alt="yucy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1076.gif" alt="dcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">-ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1100.gif" alt="softcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1096.gif" alt="shcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1084.gif" alt="mcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1103.gif" alt="yacy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1074.gif" alt="vcy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1091.gif" alt="ucy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1073.gif" alt="bcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1079.gif" alt="zcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1091.gif" alt="ucy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1096.gif" alt="shcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1085.gif" alt="ncy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1103.gif" alt="yacy" align="BASELINE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1072.gif" alt="acy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1083.gif" alt="lcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1080.gif" alt="icy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1095.gif" alt="chcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1077.gif" alt="iecy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1086.gif" alt="ocy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1081.gif" alt="jcy" align="MIDDLE" BORDER="0"> ntent/m818hh34v802h218/xxlarge1089.gif" alt="scy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1091.gif" alt="ucy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1082.gif" alt="kcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1090.gif" alt="tcy" align="BASELINE" BORDER="0">ntent/m818hh34v802h218/xxlarge1091.gif" alt="ucy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1088.gif" alt="rcy" align="MIDDLE" BORDER="0">ntent/m818hh34v802h218/xxlarge1099.gif" alt="ycy" align="BASELINE" BORDER="0">.
  相似文献   
32.
Summary Several new neutral and cationic di- and tri-nuclear cyano-bridged bis(dioximato)cobalt(III) complexes have been synthesized and characterized (dioximato = dimethylglyoximato or diphenylglyoximato). These compounds are obtained through substitution of labile axial ligands by the nitrogen of the cyano-group in [Co(dioximato)2(CN)2] or [LCo(dioximato)2(CN)] (L = H2O, NH3, or py). In the first case, the existence of only one band in the CN-stretching region of the i.r. spectrum at 2190–2200 cm–1 is indicative of a trinuclear compound, while the presence of a second band at 2140 cm–1 attributable to a terminal cyano-group indicates a dinuclear structure. In the presence of water, aquation of axial positions may take place at the same time as bridge formation, whereas the use of a non-aqueous solvent allows the preparation of complexes with pyridine or NH3.  相似文献   
33.
A new one-step facile method for the synthesis of 1,12,3,4-tetrahydro5H-5-oxo-1,4-benzo-diuzepines is described. The method involves the addition of methyl anlhranilates to elhyl-enimine followed by intramolecular cyclizalion of the resulting intermediate compounds. Another attempted method starting from β-anilinoethylisocyanales is also described.  相似文献   
34.
Two assays for the quantitative determination of the neutral and amino-monosaccharides attached to a therapeutic glycoprotein were developed using capillary zone electrophoresis (CZE) and RP-HPLC. These assays meet the strict batch release requirements of the quality control in biopharmaceutical industry. The monosaccharides were released from the glycoprotein by hydrolysis with 2N trifluoroacetic acid. In the CZE assay the monosaccharides were reacetylated prior to derivatization with 8-aminopyrenesulfonic acid (APTS), reacetylation in the glycoprotein matrix was investigated in detail. The RP-HPLC method used pre-column derivatization with anthranilic acid in methanol-acetate-borate reaction medium; reacetylation was not necessary. However, epimerization of the different monosaccharides was observed and studied in detail. For the quantitative assay, separation of the amino-monosaccharide epimers had to be developed. The HPLC assay was validated.  相似文献   
35.
The 4-pyrazoline-3-oneng class="a-plus-plus">1ng> reacts with 4-dimethylaminobenzaldehyde to yield the stable asymmetric cyanine dyeng class="a-plus-plus">2bng> which reacts withng class="a-plus-plus">1ng> to give the colorless (aryl) (dipyrazolyl) methaneng class="a-plus-plus">3bng>. Using aldehydes with less cationstabilizing groups the polymethinesng class="a-plus-plus">2ng> are not isolated but only the methanesng class="a-plus-plus">3ng>. The structures ofng class="a-plus-plus">2bng> andng class="a-plus-plus">3ng> are discussed by1 ng class="a-plus-plus">Hng>,13C and Hetero NMR spectra.  相似文献   
36.
Reaction conditions and structure of the starting enamines (cyclic or open-chain) determine greatly the final products of the title reactions. Whereas in benzene and acetonitrile, DMAD and 1 give a mixture of the diastereoisomeric dienamines 5, in methanol they afford pirrolizine 3. Enaminofuranones 2 and 10 furnish the corresponding “Michael adducts” 7a,b,c and 11a,b,c but fail to yield pirrolizines. It has been demonstrated that above b and c adducts differ exclusively on the arrangement of groups around a chiral axis.  相似文献   
37.
Hundreds of catalytic methods are developed each year to meet the demand for high-purity chiral compounds. The computational design of enantioselective organocatalysts remains a significant challenge, as catalysts are typically discovered through experimental screening. Recent advances in combining quantum chemical computations and machine learning (ML) hold great potential to propel the next leap forward in asymmetric catalysis. Within the context of quantum chemical machine learning (QML, or atomistic ML), the ML representations used to encode the three-dimensional structure of molecules and evaluate their similarity cannot easily capture the subtle energy differences that govern enantioselectivity. Here, we present a general strategy for improving molecular representations within an atomistic machine learning model to predict the DFT-computed enantiomeric excess of asymmetric propargylation organocatalysts solely from the structure of catalytic cycle intermediates. Mean absolute errors as low as 0.25 kcal mol−1 were achieved in predictions of the activation energy with respect to DFT computations. By virtue of its design, this strategy is generalisable to other ML models, to experimental data and to any catalytic asymmetric reaction, enabling the rapid screening of structurally diverse organocatalysts from available structural information.

A machine learning model for enantioselectivity prediction using reaction-based molecular representations.  相似文献   
38.
The identification of acyclic isoprenoid hydrocarbons in organic extracts of geological samples and particularly in petroleum deserves a great interest from the biological origin of the sedimentary organic matter and the understanding of geochemical processes.  相似文献   
39.
Growth of the ascomyceteChrysonilia sitophila during degradation of lignin model dimers and monomers was compared to a glucose control. An inhibition of growth by Cα-carbonyl monomers and stimulation by β-O-4 lignin model and vanillyl alcohol were observed. A comparison of the degradation by this ascomycete with the basidiomycetePhanerochaete chrysosoporium showed similarities in relation to the type of degradation caused.  相似文献   
40.
Analytical intermolecular potentials for the Fe+?H2O and Feo?H2O systems have been determined from ab initio calculations. Interaction energies for a lot of points along the two potential energy surfaces were calculated using Huzinga's MINI ?2 basis set. The results obtained were fitted to an analytical function containing 11 adjustable parameters that we have already used with success for the Fe2+?H2O system. The goodness of the generated intermolecular potentials is discussed.  相似文献   
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