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11.
Benzoylation of phenoxathiin leads to a mixture of 2- and 3-benzoylphenoxathiins. Starting from 3-phenoxathiincarbonyl chloride and benzene in the presence of anhydrous aluminum chloride, 2-benzoylphenoxathiin was obtained instead of the 3-substituted isomer. Treating 3-benzoylphenoxathiin with aluminum chloride and hydrogen chloride a rearrangement reaction took place, leading to 2-benzoylphenoxathiin.Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, Romania 76233. Romanian Academy, C. D. Nenitzescu Institute of Organic Chemistry, Splaiul Independentei, 202, Bucharest, Romania. Faculty of Pharmacy, Organic Chemistry Department, University of Medicine and Pharmacy Carol Davila, 6 Traian Vuia Street, Bucharest, Romania. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 999–1003, July, 1998. 相似文献
12.
Bukin O. A. Bazarov I. V. Maior A. Yu. Bodin N. S. Il'in A. A. Tsarev V. I. Kiselev V. D. 《Russian Physics Journal》2001,44(5):472-477
The results of experimental estimation of the fulfillment of the local thermodynamic equilibrium (LTE) criterion for the plasma generated by laser pulses of various duration at the surface of a solid target placed in a gaseous atmosphere at standard pressure are given in the present paper. The fulfillment of all the LTE criteria is demonstrated for an ensemble of neutral atoms contained in the plasma generated by a giant laser pulse or by a laser pulse whose complex shape represents several giant pulses against the background of free-running laser oscillations. The plasma excited by the radiation of a Nd : YAG laser with energy 0.4 J per pulse is examined. We have recorded a resonance broadening of atomic Al and Mg lines. This has allowed us to estimate the density of neutral atoms contained in a plasma plume. 相似文献
13.
O. A. Bukin I. V. Bazarov N. V. Bodin A. A. Il’in V. I. Tsarev A. Yu. Maior E. N. Bol’shakova 《Journal of Applied Spectroscopy》2000,67(2):320-326
This article reports the results of an experimental investigation of the basic mechanisms that cause the broadening of emission
lines of a laser-induced plasma generated on the surface of rigid targets in a gaseous atmosphere. The contribution of Stark
and resonance mechanisms of emission-line broadening for the resonance doublet Al I 3s23p2P3/2,1/2-3s24s2S1/2 and triplet Mg I 3s3p3P
0,1,2
0
-3s4s3S1 is discussed. The concentrations of neutral Al atoms in the laser-induced plasma are evaluated by the magnitude of resonance
line broadening.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 2, pp. 234–237, March–April, 2000. 相似文献
14.
Zusammenfassung Die Reaktion zwischen Palladium und Thioxanthren-3-aldoxim (I) wurde spektrophotometrisch untersucht. Mit überschüssigem I bildet sich ein mit Benzol oder Chloroform extrahierbarer Komplex. Die Extraktion mit Benzol erfolgt am besten aus einer 0,5-n salpetersauren, Quecksilbernitrat enthaltenden Lösung, da so der Einfluß von Chloridionen vermieden wird. Die Extinktion wird bei 380 nm gemessen, wo die Absorption des Reagens vernachlässigbar ist. Im Bereich 0,25-8g Pd/ml ist die Extinktion der Konzentration proportional. Zahlreiche Fremdionen stören nicht. Sulfat muß vorher mit Barium gefällt werden, Osmium und Ruthenium lassen sich durch Destillation entfernen und Gold kann durch Extraktion mit Äthylacetat oder Äther beseitigt werden. In Abwesenheit von Quecksilbernitrat bildet sich ein Komplex im Verhältnis PdR= 14, in Anwesenheit von Quecksilbernitrat im Verhältnis 16.
Spectrophotometric investigations of the reaction of palladium with thioxanthrene-3-aldoxime
Summary The reaction between palladium and thioxanthrene-3-aldoxime (I) was studied spectrophotometrically. A complex that can be extracted with benzene or chloroform is produced with excess of I. The extraction with benzene succeeds best from 0.5M solution containing nitric acid and mercuric nitrate so that the influence of chloride ions is averted. The extinction is measured at 380 nm, where the absorption of the reagent is negligible. The extinction is proportional to the concentration in the region 0.25–8g Pd/ml. Numerous foreign ions do not interfere. Sulfate must be removed previously by precipitation with barium; osmium and ruthenium can be removed by distillation, and gold can be removed by extraction with ethylacetate or ether. In the absence of mercuric nitrate there is formed a complex in the ratio of PdR=14, while in the presence of mercury nitrate the ratio is 16.相似文献
15.
Zemlyanov A. A. Babushkin P. A. Golik S. S. Donchenko V. A. Zemlyanov Al. A. Maior A. Yu. Oshlakov V. K. Ryambov R. V. Trifonova A. V. 《Russian Physics Journal》2022,64(11):2151-2154
Russian Physics Journal - The paper presents the femtosecond laser filamentation, which splits the liquid spray into two jets. The dependence is suggested for the acoustic signal and the... 相似文献
16.
Maior Luane de Oliveira de Almeida Vanessa Soltes Barretti Barbara Ruivo Válio Ito Vivian Cristina Beninca Cleoci Demiate Ivo Mottin Schnitzler Egon Carvalho Filho Marco Aurélio Da Silva Lacerda Luiz Gustavo 《Journal of Thermal Analysis and Calorimetry》2021,143(1):265-273
Journal of Thermal Analysis and Calorimetry - Maize is the most important source of starch used for industrial applications. Its starch properties can be improved by either single or double... 相似文献
17.
Ossamu Hojo Carlos Osamu Hokka Ana Maria Souto Maior 《Applied biochemistry and biotechnology》1999,78(1-3):535-545
Tests were performed in a continuous stirred tank reactor (CSTR), with and without cell recycling, to produce ethanol. The
reactor without cell recycling produced the kinetic model of ethanol production, whereas the reactor with cell recycling allowed
for a study of process stability.
The Levenspiel kinetic model was adopted; however, in the case of fermentation with cell recycling, the coefficient of cell
death was added. It was observed that cellular viability varied greatly throughout the fermenting process and that microaeration
is of fundamental importance in maintaining the stability of the process. 相似文献
18.
N. Badicu T. Loloiu D. Gavriliu G. Loloiu O. Maior 《Chemistry of Heterocyclic Compounds》1999,35(12):1474-1479
The reactions of phenoxathiin-2-carbonyl-or thianthrene-2-carbonyl-isothiocyanates with certain primary amines lead to the formation of corresponding N-substituted-N-hetaroylthiocarbamides. The aforementioned isothiocyanates were obtained in situ by reactions of phenoxathiin-2-or thianthrene-2-carbonyl chlorides with KSCN. The new compounds were characterized by elemental analysis and spectral data (IR,1H and13C NMR).Analytical Laboratory-Biofarm, 99 Logofat Tautu Street, Bucharest, Roumania. Faculty of Pharmacy, Organic Chemistry Departament, University of Medicine and Pharmacy Carol Davila, 6 Traian Vuia Street, Bucharest, Roumania, Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, 76233, RoumaniaPublished in Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1681–1686, December, 1999. 相似文献
19.
D. Gavriliu T. Loloiu A. Nicolae G. Loloiu O. Maior 《Chemistry of Heterocyclic Compounds》2002,38(2):242-248
The Kröhnke reaction of 2-bromoacetylphenoxathiin and 2--bromophenoxathiin 10,10-dioxide, through N-ylide and S-ylide intermediates, leading to the corresponding glyoxals, was described. The condensation reaction of 2--bromoacetylphenoxathiin with aromatic o-hydroxy aldehydes and further cyclization to new furan derivatives was also performed. The new compounds were characterized through elemental analysis and spectral data (IR, 1H NMR and 13C NMR). 相似文献
20.
CF is an inherited autosomal recessive disease whose lethality arises from malfunction of CFTR, a single chloride (Cl-) ion channel protein. CF patients harbor mutations in the CFTR gene that lead to misfolding of the resulting CFTR protein, rendering it inactive and mislocalized. Hundreds of CF-related mutations have been identified, many of which abrogate CFTR folding in the endoplasmic reticulum (ER). More than 70% of patients harbor the DeltaF508 CFTR mutation that causes misfolding of the CFTR proteins. Consequently, mutant CFTR is unable to reach the apical plasma membrane of epithelial cells that line the lungs and gut, and is instead targeted for degradation by the UPS. Proteins located in both the cytoplasm and ER membrane are believed to identify misfolded CFTR for UPS-mediated degradation. The aberrantly folded CFTR protein then undergoes polyubiquitylation, carried out by an E1-E2-E3 ubiquitin ligase system, leading to degradation by the 26S proteasome. This ubiquitin-dependent loss of misfolded CFTR protein can be inhibited by the application of 'corrector' drugs that aid CFTR folding, shielding it from the UPS machinery. Corrector molecules elevate cellular CFTR protein levels by protecting the protein from degradation and aiding folding, promoting its maturation and localization to the apical plasma membrane. Combinatory application of corrector drugs with activator molecules that enhance CFTR Cl- ion channel activity offers significant potential for treatment of CF patients. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com). 相似文献