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991.
Mohammad M. Mojtahedi Mohammad Saeed Abaee Mohammad Mehdi Zahedi Mohammad R. Jalali A. Wahid Mesbah Werner Massa Roholah Yaghoubi Mehdi Forouzani 《Monatshefte für Chemie / Chemical Monthly》2008,31(2):917-921
A remarkably efficient procedure for the synthesis of styrylcyclohex-2-enone derivatives at room temperature is described
using a mild reaction medium consisting of lithium perchlorate and N-(trimethylsilyl)diethylamine. Several compounds of this class are synthesized conveniently and rapidly. Spectroscopic and
X-ray diffraction experiments confirm the proposed structures. 相似文献
992.
The mono- and bis-iodo-substituted NHC-stabilized alanes (NHC) ⋅ AlH2I and (NHC) ⋅ AlHI2 offer a convenient entry for further substitution reactions at aluminum. Reactions of (NHC) ⋅ AlH2I 1 – 4 with one equivalent of NaCp afforded the adducts (NHC) ⋅ AlH2Cp 9 – 12 (NHC=Me2ImMe ( 9 ), iPr2ImMe ( 10 ), iPr2Im ( 11 ), Dipp2Im ( 12 )). Alane adducts with two Cp substituents (NHC) ⋅ AlHCp2 13 – 16 (NHC=Me2ImMe ( 13 ), iPr2ImMe ( 14 ), iPr2Im ( 15 ), Dipp2Im ( 16 )) were prepared by the analogous reaction of (NHC) ⋅ AlHI2 5 – 8 using two equivalents of NaCp. The unusual dimeric adducts ((NHC) ⋅ AlH2Cp ⋅ CpMgI)2 17 – 19 (NHC=Me2ImMe ( 17 ), iPr2ImMe ( 18 ), iPr2Im ( 19 )) were obtained from the reaction of 1 – 3 with MgCp2. 相似文献
993.
A detailed investigation is made of the continuity, the compactness and the spectrum of the Cesàro operator \(\mathsf {C}\) acting on the weighted Banach sequence space \(c_0(w)\) for a bounded, strictly positive weight w. New features arise in the weighted setting (e.g. existence of eigenvalues, compactness, mean ergodicity) which are not present in the classical setting of \(c_0\). 相似文献
994.
Reference spectra of important adsorbed organic and inorganic phosphate binding forms for soil P speciation using synchrotron‐based K‐edge XANES spectroscopy 下载免费PDF全文
Jörg Prietzel Gertraud Harrington Werner Häusler Katja Heister Florian Werner Wantana Klysubun 《Journal of synchrotron radiation》2016,23(2):532-544
Direct speciation of soil phosphorus (P) by linear combination fitting (LCF) of P K‐edge XANES spectra requires a standard set of spectra representing all major P species supposed to be present in the investigated soil. Here, available spectra of free‐ and cation‐bound inositol hexakisphosphate (IHP), representing organic P, and of Fe, Al and Ca phosphate minerals are supplemented with spectra of adsorbed P binding forms. First, various soil constituents assumed to be potentially relevant for P sorption were compared with respect to their retention efficiency for orthophosphate and IHP at P levels typical for soils. Then, P K‐edge XANES spectra for orthophosphate and IHP retained by the most relevant constituents were acquired. The spectra were compared with each other as well as with spectra of Ca, Al or Fe orthophosphate and IHP precipitates. Orthophosphate and IHP were retained particularly efficiently by ferrihydrite, boehmite, Al‐saturated montmorillonite and Al‐saturated soil organic matter (SOM), but far less efficiently by hematite, Ca‐saturated montmorillonite and Ca‐saturated SOM. P retention by dolomite was negligible. Calcite retained a large portion of the applied IHP, but no orthophosphate. The respective P K‐edge XANES spectra of orthophosphate and IHP adsorbed to ferrihydrite, boehmite, Al‐saturated montmorillonite and Al‐saturated SOM differ from each other. They also are different from the spectra of amorphous FePO4, amorphous or crystalline AlPO4, Ca phosphates and free IHP. Inclusion of reference spectra of orthophosphate as well as IHP adsorbed to P‐retaining soil minerals in addition to spectra of free or cation‐bound IHP, AlPO4, FePO4 and Ca phosphate minerals in linear combination fitting exercises results in improved fit quality and a more realistic soil P speciation. A standard set of P K‐edge XANES spectra of the most relevant adsorbed P binding forms in soils is presented. 相似文献
995.
Angela A. Albanese José Bonet Werner J. Ricker 《Integral Equations and Operator Theory》2016,86(1):97-112
The Cesàro operator C, when acting in the classical growth Banach spaces \({A^{-\gamma}}\) and \({A_0^{-\gamma}}\), for \({\gamma} > 0\), of analytic functions on \({\mathbb{D}}\), is investigated. Based on a detailed knowledge of their spectra (due to A. Aleman and A.-M. Persson) we are able to determine the norms of these operators precisely. It is then possible to characterize the mean ergodic and related properties of C acting in these spaces. In addition, we determine the largest Banach space of analytic functions on \({\mathbb{D}}\) which C maps into \({A^{-\gamma}}\) (resp. into \({A_0^{-\gamma}}\)); this optimal domain space always contains \({A^{-\gamma}}\) (resp. \({A_0^{-\gamma}}\)) as a proper subspace. 相似文献
996.
Grombe R Gouzy MF Maitz MF Freundenberg U Zschoche S Simon F Pompe T Sperling C Werner C 《Macromolecular bioscience》2007,7(2):195-200
The impact of heparinoid characteristics on model surfaces obtained from immobilization of sole sulfate groups as well as sulfated glycosides, sulfated cellulose, and definite heparin has been investigated. The obtained layers were physico-chemically characterized regarding film thickness, chemical composition, wettability, and surface morphology. Antithrombin adsorption, studied by fluorescence labeling, revealed a strong dependence on the presence of glycosidic structures and on the molecular weight of the grafted saccharide. On contact with whole blood, the coatings resulted in a diminished plasmatic and cellular coagulation in vitro, which did not reflect well the antithrombin binding. Therefore, more complex activating pathways are discussed. 相似文献
997.
998.
García Suárez EJ Ruiz A Castillón S Oberhauser W Bianchini C Claver C 《Dalton transactions (Cambridge, England : 2003)》2007,(27):2859-2861
Two novel bis(o-methoxyphenyl) phosphinoalkylsulfonate (P-O) ligands have been prepared through a new and sustainable synthetic route; they are air stable as well as water soluble and have been applied in Pd-catalysed Suzuki-Miyaura cross-coupling reactions in neat water in conjunction with microwave heating. 相似文献
999.
A spectroscopic method based on attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy has been developed
for reagent-free analysis of blood and urine constituents in the clinical laboratory and for point-of-care-applications. Blood
plasma, whole blood, and urine were analyzed without any sample preparation, such as drying, concentration, or enrichment.
Sample volumes as small as 5 μL (a single drop of blood) can be used. Mathematical models, including partial least-squares
regression, were used to construct a prediction model which can calculate the concentration of albumin, cholesterol, glucose,
total protein, urea, and triglycerides in whole blood or blood plasma samples and the concentration of urea, uric acid, phosphate
and creatinine in urine samples. The absolute precision and reproducibility of the prediction reached is sufficient for routine
clinical analysis and is only limited by the precision of the reference analysis used for calibration. This was achieved by
use of a large number of calibration samples (approx. 400 for blood samples and approx. 100 for urine samples) carefully selected
for physiological and pathological range and for specific disease profiles. 相似文献
1000.
Guillermo P. Curbera Werner J. Ricker 《Journal of Mathematical Analysis and Applications》2007,328(1):287-294
New features of the Banach function space , that is, the space of all ν-scalarly pth power integrable functions (with 1?p<∞ and ν any vector measure), are presented. The Fatou property plays an essential role and leads to a new representation theorem for a large class of abstract p-convex Banach lattices. 相似文献