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991.
Árpád Balázs Anasztázia Hetényi Dr. Zsolt Szakonyi Dr. Reijo Sillanpää Prof. Dr. Ferenc Fülöp Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(30):7376-7381
The PdII‐catalyzed intramolecular oxidative cyclization of tosyl‐protected cis‐ and trans‐N‐allyl‐2‐aminocyclohexanecarboxamides was examined, and efficient syntheses of cyclohexane‐fused pyrimidin‐4‐ones and 1,5‐diazocin‐6‐ones were developed. In the course of the research, a marked solvent effect was observed on both the regio‐ and diastereoselectivity. Additionally, a novel PdII‐mediated domino oxidation, oxidative amination reaction was discovered. Our experimental and theoretical findings suggest that the reactions proceed via a cis‐aminopalladation mechanism. 相似文献
992.
Susana García‐Martín Ulises Amador Ainhoa Morata‐Orrantia Juan Rodríguez‐Carvajal Miguel Ángel Alario‐Franco Prof. Dr. 《无机化学与普通化学杂志》2009,635(15):2363-2373
The very high value of ionic conductivity at room temperature reported for La0.51Li0.34TiO2.94 some years ago did originate a great deal of interest in the study of materials of general formula La2/3–xLi3xTiO3 (LaLiTiO) and related systems. These oxides have shown to be potential solid electrolytes for lithium secondary batteries, but other aspects, apart from the conducting properties, such as their dielectric behaviour and crystal structure, have been the main focus of important studies in the area of inorganic solid‐state chemistry. LaLiTiO‐related compounds have the perovskite‐type structure (ABO3) with A‐cation ordering. However, essential details of their crystal structure, as for instance the location of the lithium atoms, are still under discussion and are the subject of current work. We show in this short review of mainly our own work that the complex microstructure of these materials, which has been studied in detail by transmission electron microscopy, is the cause of the difficulties on the precise determination of their crystal structure. We have developed a new approach for crystal structure refinement, which takes into account the microstructural effects, obtaining significantly better results than conventional methods of refinement. The microstructure of these oxides also affects their conducting and dielectric properties. Therefore, different parameters such as composition and microstructure must be considered to understand and, eventually, optimise, as we have done, the conducting properties of LaLiTiO‐related systems. 相似文献
993.
We give a necessary modification of Proposition 1.18 in Nagy and Strambach (Loops in Group Theory and Lie Theory. de Gruyter
Expositions in Mathematics Berlin, New York, 2002) and close the gap in the classification of differentiable Bol loops given
in Figula (Manuscrp Math 121:367–385, 2006). Moreover, using the factorization of Lie groups we determine the simple differentiable
proper Bol loops L having the direct product G
1 × G
2 of two groups with simple Lie algebras as the group topologically generated by their left translations such that the stabilizer
of the identity element of L is the direct product H
1 × H
2 with H
i
< G
i
. Also if G
1 = G
2 = G is a simple permutation group containing a sharply transitive subgroup A, then an analogous construction yields a simple proper Bol loop. If A is cyclic and G is finite and primitive, then all such loops are classified. 相似文献
994.
Israel Bautista-Hernndez Cristbal N. Aguilar Guillermo C. G. Martínez-vila Cristian Torres-Len Anna Ilina Adriana C. Flores-Gallegos Deepak Kumar Verma Mnica L. Chvez-Gonzlez 《Molecules (Basel, Switzerland)》2021,26(17)
Lippia graveolens is a traditional crop and a rich source of bioactive compounds with various properties (e.g., antioxidant, anti-inflammatory, antifungal, UV defense, anti-glycemic, and cytotoxicity) that is primarily cultivated for essential oil recovery. The isolated bioactive compounds could be useful as additives in the functional food, nutraceuticals, cosmetics, and pharmaceutical industries. Carvacrol, thymol, β-caryophyllene, and p-cymene are terpene compounds contained in oregano essential oil (OEO); flavonoids such as quercetin O-hexoside, pinocembrin, and galangin are flavonoids found in oregano extracts. Furthermore, thermoresistant compounds that remain in the plant matrix following a thermal process can be priced in terms of the circular economy. By using better and more selective extraction conditions, the bioactive compounds present in Mexican oregano can be studied as potential inhibitors of COVID-19. Also, research on extraction technologies should continue to ensure a higher quality of bioactive compounds while preventing an undesired chemical shift (e.g., hydrolysis). The oregano fractions can be used in the food, health, and agricultural industries. 相似文献
995.
Árpád Kurusa 《Aequationes Mathematicae》2018,92(5):949-961
Euclidean geometry is the only Minkowski geometry in which either there is a centrally symmetric, or a quadratic conic, or there is a conical ellipsoid or hyperboloid. 相似文献
996.
Fernando de Ávila Silva Todor Gramchev Alexandre Kirilov 《Journal d'Analyse Mathématique》2018,135(2):527-573
The main goal of this paper is to address global hypoellipticity issues for the class of first-order pseudo-differential operators L = Dt + C(t, x,Dx), where (t, x) ∈ T × M, T is the one-dimensional torus, M is a closed manifold, and C(t, x,Dx) is a first-order pseudo-differential operator on M, smoothly depending on the periodic variable t. In the case of separation of variables, when C(t, x,Dx) = a(t)p(x,Dx) + ib(t)q(x,Dx), we give necessary and sufficient conditions for the global hypoellipticity of L. In particular, we show that the famous (P) condition of Nirenberg-Treves is neither necessary nor sufficient to guarantee the global hypoellipticity of L. 相似文献
997.
We use high-frequency data from the Nasdaq exchange to build a measure of volume imbalance in the limit order (LO) book. We show that our measure is a good predictor of the sign of the next market order (MO), i.e., buy or sell, and also helps to predict price changes immediately after the arrival of an MO. Based on these empirical findings, we introduce and calibrate a Markov chain-modulated pure jump model of price, spread, LO and MO arrivals and volume imbalance. As an application of the model, we pose and solve a stochastic control problem for an agent who maximizes terminal wealth, subject to inventory penalties, by executing trades using LOs. We use in-sample-data (January to June 2014) to calibrate the model to 11 equities traded in the Nasdaq exchange and use out-of-sample data (July to December 2014) to test the performance of the strategy. We show that introducing our volume imbalance measure into the optimization problem considerably boosts the profits of the strategy. Profits increase because employing our imbalance measure reduces adverse selection costs and positions LOs in the book to take advantage of favourable price movements. 相似文献
998.
Mateo Alajarín Prof. Carmen López‐Leonardo Dr. Ángel Álvarez‐García Pilar Llamas‐Lorente Dr. Pilar Sánchez‐Andrada Dr. José Berná Dr. Aurelia Pastor Dr. Delia Bautista Dr. Peter G. Jones Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(12):3728-3735
A series of N,P,P‐trisubstituted aminophosphanes react with diphenylcyclopropenone to afford an easily separable mixture of two diastereomeric α,β‐diphenyl‐β‐phosphinoyl carboxamides in good yields. X‐ray crystal structures reveal that these compounds associate into dimers, formed from two enantiomeric units linked by two bifurcated hydrogen bonds, whereby the oxygen atom of the phosphoryl group acts as a dual acceptor for the vicinal NH and CH of a carbonyl group of a neighbouring molecule. Studies on the interconversion between diastereomeric phosphinoyl carboxamides in basic solution show that the thermodynamically most stable isomer depends on the nature of the substituent at the nitrogen atom. Simple computational calculations explain this phenomenon. 相似文献
999.
Frank J. Millero J. Magdalena Santana-Casiano Melchor González-Dávila 《Journal of solution chemistry》2010,39(4):543-558
The inorganic behavior of most divalent metals in natural waters is affected by the formation of carbonate complexes. The
acidification of the oceans will lower the carbonate concentration in the oceans. This will increase the concentration of
free copper that is toxic to marine organisms. To be able to determine the effect of this acidification, reliable stability
constants are needed for the formation of copper carbonate complexes. In this paper, the speciation of Cu(II) with bicarbonate
and carbonate ions
${rcl}&&\mathrm{Cu}^{2+}+\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{CuCO}_{3(\mathrm{aq})}+\mathrm{H}^{+}\\[4pt]&&\mathrm{Cu}^{2+}+2\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{Cu}(\mathrm{CO}_{3})_{2}^{2-}+2\mathrm{H}^{+}\\[4pt]&&\mathrm{Cu}^{2+}+\mathrm{CO}_{3}^{2-}\rightleftharpoons \mathrm{CuCO}_{3(\mathrm{aq})}\\[4pt]&&\mathrm{Cu}^{2+}+2\mathrm{CO}_{3}^{2-}\rightleftharpoons \mathrm{Cu}(\mathrm{CO}_{3})_{2}^{2-}\\[4pt]&&\mathrm{Cu}^{2+}+\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{CuHCO}_{3}^{+}$\begin{array}{rcl}&&\mathrm{Cu}^{2+}+\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{CuCO}_{3(\mathrm{aq})}+\mathrm{H}^{+}\\[4pt]&&\mathrm{Cu}^{2+}+2\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{Cu}(\mathrm{CO}_{3})_{2}^{2-}+2\mathrm{H}^{+}\\[4pt]&&\mathrm{Cu}^{2+}+\mathrm{CO}_{3}^{2-}\rightleftharpoons \mathrm{CuCO}_{3(\mathrm{aq})}\\[4pt]&&\mathrm{Cu}^{2+}+2\mathrm{CO}_{3}^{2-}\rightleftharpoons \mathrm{Cu}(\mathrm{CO}_{3})_{2}^{2-}\\[4pt]&&\mathrm{Cu}^{2+}+\mathrm{HCO}_{3}^{-}\rightleftharpoons \mathrm{CuHCO}_{3}^{+}\end{array} 相似文献
1000.
α-1-acid glycoprotein (AGP) is a highly heterogeneous protein that presents a vast number of isoforms (molecules of the protein differing in its peptidic and/or glycosidic moieties). In the last years, several authors have studied the potential use of AGP as a cancer biomarker. These studies focus on the correlation of different features of AGP structure (i.e. fucosylation, antennarity) with cancer or on the total protein blood concentration. In this study, the potential of CZE-UV and CZE-ESI-MS analysis of intact AGP isoforms to study the correlation of this protein with bladder cancer is shown. Samples from 16 individuals (eight healthy, eight bladder cancer) were analyzed and characterized in great detail including data on intact protein isoforms and on released glycans. The analytical data were evaluated employing different statistical techniques (ANOVA; principal component analysis, PCA; linear discriminant analysis; and partial least squares-discriminant analysis). Statistical differences between the two groups of study were observed. The best results were obtained by linear discriminant analysis of the CZE-ESI-MS data for intact AGP isoforms (93.75% of correct classification). Due to MS characterization, it can be observed that differences between the samples are mainly due to higher abundance of AGP isoforms containing tri- and tetra-antennary fucosylated oligosaccharides in cancer patients. The results show the great potential of CE-MS in combination with advanced data processing for the use of intact protein isoforms as disease biomarkers. 相似文献
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