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61.
Five chiral -D-glucose-based monoaza-15-crown-5 ethers with phosphinoxidoalkyl side chains of one to five carbon atoms (5a–e)have been synthesised. The cation binding ability of the new lariat ethers was evaluated bythe picrate extraction method. The substituents at the nitrogen atom were not a major influenceon the cation extraction ability of the azacrown ether; the compounds showed, however, a significant asymmetric induction as phase transfer catalysts in the Michael addition of2-nitropropane to chalcone (95% ee).  相似文献   
62.
N&#;meth  Krisztina  Kremmer  Tibor  Kocsis  L&#;szl&#;  Visy  J&#;lia 《Chromatographia》2009,69(11):1307-1313

A novel capillary zone electrophoresis method was developed to investigate the glycoform heterogeneity of human serum α1-acid glycoprotein (AGP). The simultaneous application of a dimethyl polysiloxane coated capillary and oligoamine additives, particularly spermidine resulted in a more detailed separation of AGP glycoforms than reported previously. The relative distribution of AGP glycoforms in CZE was determined by baseline integration of peak areas and verified by peak-fitting analysis. Providing high purity of AGP samples suitable for CZE a schedule of isolation and purification steps including sample preparation and an improved technique of ion exchange chromatography was applied. Based on data obtained by CZE and on the serum AGP levels measured the serum concentrations of AGP glycoforms were calculated in cancer patients with Hodgkin and non-Hodgkin lymphoma, ovary carcinoma and melanoma compared to healthy donors. Results presented here demonstrated a significant increase in the serum concentration of the more acidic AGP fractions also indicating the overproduction of these glycoforms in cancer. In conclusion, our observations may raise the clinical diagnostic relevance of changes in the molecular heterogeneity of AGP detected by CZE in the various forms of malignant diseases.

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63.
Rendiconti del Circolo Matematico di Palermo Series 2 -  相似文献   
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A new efficient interval partitioning approach to solve constrained global optimization problems is proposed. This involves a new parallel subdivision direction selection method as well as an adaptive tree search. The latter explores nodes (intervals in variable domains) using a restricted hybrid depth-first and best-first branching strategy. This hybrid approach is also used for activating local search to identify feasible stationary points. The new tree search management technique results in improved performance across standard solution and computational indicators when compared to previously proposed techniques. On the other hand, the new parallel subdivision direction selection rule detects infeasible and suboptimal boxes earlier than existing rules, and this contributes to performance by enabling earlier reliable deletion of such subintervals from the search space.  相似文献   
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Ohne ZusammenfassungD 91 (München 1941). XV. Mitteilung über reversible Polymerisate von G. Scheibe und Mitarbeitern. — Bisher sind erschienen: I. Angew. Chem.49, 563 (1936); II. Angew. Chem.50, 51 und 212 (1937); III. Angew. Chem.52, 631 (1939); IV. Naturwiss.25, 75 (1937); V. Naturwiss.25, 474 (1937); VI. Naturwiss.25, 795 (1937); VII. Naturwiss.26, 412/413 (1938); VIII. Naturwiss.27, 499 (1939); IX. Kolloid-Z.82, 1 (1938); X. Z. wiss. Photogr.38, 1 (1939); XI. Kolloid-Z.92, 35 (1940) [H. Ecker]; XII. Kolloid-Z.92, 299 (1940) und93, 28. (1940) [F. Katheder]; XIII. Z. wiss. Photogr.39, 18 (1940) [A. Schöntag]; XIV. Z. Elektrochem.47, 73 (1941).  相似文献   
69.
An efficient resolution method was elaborated for the preparation of (+)‐4‐chloro‐5‐methyl‐1‐phenyl‐1,2,3,6‐tetrahydrophosphinine oxide using the acidic Ca2+ salt of (–)‐O,O‐di‐p‐toluoyl‐(2R,3R)‐tartaric acid. Crystal structure of the diastereomeric complex was evaluated by single crystal X‐ray analysis. Beside this, the absolute P‐configuration was also determined by a circular dichroism (CD) spectroscopic study including theoretical calculations. The tetrahydrophosphinine oxide was then converted to the corresponding platinum complex whose stereostructure was investigated by high‐level quantum chemical calculations. The Pt complex was tested as a catalyst in the hydroformylation of styrene.  相似文献   
70.
Hungary is rich in spring waters. A survey studying the naturally occurring alpha emitter radionuclides in 30 frequently visited and regularly consumed spring waters was conducted out in the Balaton Upland region of Hungary.226Ra, 224Ra, 234U, 238U and 210Po activity concentrations were determined by using alpha spectrometry after separation from matrix elements. Average concentration (mBq L− 1) of 226Ra, 224Ra, 234U, 238U and 210Po in the spring waters is varied from 2.1 to 601, from < 1.1 to 65.4, from 3.9 to 741.9, from < 0.44 to 274.3 and from 2 to 15.2 respectively. In most cases radioactive disequilibrium was observed between uranium and radium isotopes. The doses for the analyzed samples of spring water are in the range 3.59–166.73 μSv y− 1 with an average 18.2 μSv y− 1 .This is well below the 100 μSv y− 1 reference level of the committed effective dose recommended by WHO. Only one water sample had a dose higher than 100 μSv y− 1, mainly due to the contribution from radium (226Ra, 224Ra) and 210Po isotopes. This study provides important information for consumers and authorities about their internal radiological exposure risk from spring water intake.  相似文献   
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