Estimation of the Sorption Activity of Silver Nanoparticles on Biodegradable Fibers of Natural and Artificial Origin

Russian Physics Journal - The specific features of the sorption activity of silver nanoparticles (AgNPs) on biodegradable polymers of natural (collagen) and artificial (polyamide 6.6) origin have...     

On the Generation of Intense Cs K X-Rays upon Electron Excitation of a Mo Target Heat Treated in Cs and O2 Vapors

JETP Letters - The possibility of stable generation of intense characteristic Cs radiation upon electronic excitation of a Mo anode target heat treated in Cs and O2 vapors is demonstrated. The...     

广义风险过程中渐近方差的非参数估计

本文对广义风险过程中的渐近方差作了非参数估计,得出并证明了两个定理,为广义风险过程中破产概率的区间估计作了理论准备．     

3,3,6,6-四甲基-9-邻氯苯基-1,8-二氧代-3,4,5,6,7,9-六氧化氧杂蒽的合成和晶体结构

标题化合物C23H25对O3Cl是由邻氯苯甲醛与5，5-二甲基1，3-环己二酮在N，N-二甲基甲酸腹中反应而得。结构通过单晶X-射线衍射法确定，其晶体属于单科晶系，空间群=1632。晶体结构用直接法解出，使用全矩阵最小二乘法对原子参数进行修正，最后的偏离因子为R=0．054，Rw一0．063。在晶体结构中，吡喃环与苯环之间的两面角为92．43°。     

Reaction of Methylcyclohexanones with Substituted Benzaldehydes and 2-Naphthylamine

Cascade heterocyclization of 3(4)-methylcyclohexanone, substituted benzaldehyde, and 2-naphthyl-amine in a polar solvent in the presence of hydrochloric acid afforded the corresponding 5-aryl-2(3)-methyl-1,2,3,4-tetrahydrobenzo[a]phenanthridines and 12-aryl-9(10)-methyl-8,9,10,11-tetrahydrobenz[a]acridines     

Crystal and molecular structures of 2,10-diacetoxy-13-thiabicyclo[7.3.1]-cis-tridec-5-ene and 2,9-dichloro-13-thiabicyclo[8.2.1]-cis-tridec-5-ene sulfoxide

The crystal and molecular structures of 2,10-diacetoxy-13-thiabicyclo[7.3.1]-cis-tridec-5-ene and 2,9-dichloro-13-thiablcyclo[8.2.1]-cis-tridec-5-ene sulfoxide were established. The conformations of the molecules are such that the unshared pairs of electrons of the sulfur atoms are directed to the carboncarbon double bonds of their molecules. It was observed that there are stereochemical conditions for transannular transformations under the influence of polarized molecules and cations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1628–1632, December, 1977.     

Total Synthesis of Several 8, 8",-Biflavones

8,8"-Biflavonoidsareantw0rtantclass0fbiflavonoids.Asasystematicresearchofthe8,8"-biflav0noids,wehavepreviouslyreportedthestudyonthereactionof2'-hydroxychaloneswithl2-H2SO4-DMSOsystem.'InthispaPer,thesynthesisof5,5",7,7',-tetTameth0xy-8,8"-biflavonela2,4,4",7,7"-tetramethoxy-8,8"-biflavone1b',4',4",,5,5,',7,7"-hexamethoxy-8,8"-biflav0ne1c4and4,4"-dibenZyl0xy-5,5",7,7"-tetramothoxy-8,8"-biflavoneldisreported.ThesyntheticmethodisshownintheSchemebelow.2-Hydroxyacet0phenonescondensedwithsubsti…     

Glycosides of (+)-syringaresinol and 2-methylbut-3-en-2-yl β-D-glucopyranoside from the leaves ofNolina microcarpa

Two furofuranoid lignan glycosides, having the structures of (+)-syringaresinol 4′,4″-di-β-D-glucopyranoside (1) and (+)-syringaresinol 4′-β-D-glucopyranoside (2), and also 2-methylbut-3-en-2-yl β-D-glucopyranoside (3), have been isolated from an extract of the leaves ofNolina microcarpa (fam. Dracaenaceae).     

Synthesis of the pentasaccharide repeating unit of the O-specific polysaccharide from salmonella strasbourg

The pentasaccharide α - Tyv - (1→3) - β - d - Man - (1→4) - α - l - Rha - (1→3) - d - Gal - (4←1) -α - d - Glc 1, the repeating unit of the O-specific polysaccharide chain of the lipopolysaccharide from S. Strasbourg, was obtained by glycosylation of benzyl - 2,6 - di - O - benzyl - 4 - O - (2,3,4 - tri - O - benzyl - 6 - O - benzoyl - α - d - glucopyranosyl) - β - d - galactopyranoside with 1,2 - methylorthoacetyl - 3 - O - acetyl - 4- O - [3 - O - (2,4 - di - O - acetyl - 3, 6 - dideoxy,- α - d - arabino - hexopyranosyl) - 2,4,6 - tri - O - acetyl - β - d - mannopyranosyl] - β - l - rhamnopyranose 3 followed by removal of protecting groups. The structure of the synthetic pentasaccharide was proved by methylation analysis and ¹³C NMR.