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771.
We begin a coarse geometric study of Hilbert geometry. Actually we give a necessary and sufficient condition for the natural boundary of a Hilbert geometry to be a corona, which is a nice boundary in coarse geometry. In addition, we show that any Hilbert geometry is uniformly contractible and with coarse bounded geometry. As a consequence of these we see that the coarse Novikov conjecture holds for a Hilbert geometry with a mild condition. Also we show that the asymptotic dimension of any two-dimensional Hilbert geometry is just two. This implies that the coarse Baum–Connes conjecture holds for any two-dimensional Hilbert geometry via Yu’s theorem.
相似文献772.
Dr. Kojiro Fuku Honami Kanai Masanobu Todoroki Nanako Mishima Taisei Akagi Dr. Takashi Kamegawa Prof. Naoki Ikenaga 《化学:亚洲杂志》2021,16(14):1887-1892
Water pollution derived from organic pollutants is one of the global environmental problems. The Fenton reaction using Fe2+ as a homogeneous catalyst has been known as one of clean methods for oxidative degradation of organic pollutants. Here, a layered double hydroxide (Fe2+Al3+-LDH) containing Fe2+ and Al3+ in the structure was used to develop a “heterogeneous” Fenton catalyst capable of mineralizing organic pollutants. We found that sulfate ion (SO42−) immobilized on the Fe2+Al3+-LDH significantly facilitated oxidative degradation (mineralization) of phenol as a model compound of water pollutants to carbon dioxide (CO2) in a heterogeneous Fenton process. The phenol conversion and mineralization efficiency to CO2 reached >99% and ca. 50%, respectively, even with a reaction time of only 60 min. 相似文献
773.
Dr. Kosuke Nakashima Anton Petek Yutaro Hori Dr. Anton Georgiev Dr. Shin-ichi Hirashima Dr. Yasuyuki Matsushima Dr. Dancho Yordanov Prof. Dr. Tsuyoshi Miura Prof. Dr. Liudmil Antonov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(45):11559-11566
The reimagined concept of long-range tautomeric proton transfer using crane subunits is shown by designing and synthesising two new acylhydrazones containing a 7-hydroxyquinoline (7-OHQ) platform. The acylhydrazone subunits attached to the 7-OHQ at the 8th position act as crane arms for delivering proton cargo to the quinoline nitrogen. Light-induced tautomerization to their keto forms leads to Z/E isomerization of the C=C axle bond, followed by proton delivery to the quinoline nitrogen by the formation of covalent or hydrogen bonds. The axle‘s being either an imine or ketimine bond is the structural difference between the studied compounds. The −CH3 group in the latter provides steric strain, resulting in different proton transport pathways. Both compounds show long thermal stability in the switched state, which creates a tuneable action of bidirectional proton cargo transport by using different wavelengths of irradiation. Upon the addition of acid, the quinoline nitrogen is protonated; this results in E/Z configuration switching of the acylhydrazone subunits. This was proven by single-crystal X-ray structure analysis and NMR spectroscopy. 相似文献
774.
A cell specific peptide (Arg‐Gly‐Asp; RGD)‐modified nanogel was prepared and evaluated for its potential to act as a protein delivery carrier. A bovine serum albumin (BSA)/RGD‐modified nanogel complex was efficiently internalized into cells through integrin‐mediated endocytosis. Endosomal escape of the RGD‐modified nanogel was observed after 24 h incubation. The nanogel proved useful for targeted protein delivery.
775.
Ogata K Shimada D Fukuzawa S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(20):6142-6146
Running rings: The first regio- and stereoselective reductive coupling between methylenecyclopropanes, aldehydes, and triethylborane with retention of the cyclopropane ring was achieved using a nickel-phosphine catalyst (see scheme). The reductive coupling reaction constructed a stereo-defined cyclopropane ring with formation of a quaternary stereogenic carbon center. 相似文献
776.
The reaction of the ε-Keggin polyoxometalate (POM) [PMo(12)O(36)(OH)(4){La(H(2)O)(4)}(4)](5+) with Fe(II)(CN)(6)(4-) under typical bench conditions at room temperature and ambient pressure has afforded the novel [ε-PMo(12)O(37)(OH)(3){La(H(2)O)(5)(Fe(CN)(6))(0.25)}(4)] network, which exhibits a three-dimensional multilayered structure. The compound has been fully characterized by synchrotron-radiation X-ray crystallography, IR spectroscopy, elemental analysis, and thermogravimetric analysis. This coordination network constitutes the first example of a cyanometalate bonded to a POM unit. 相似文献
777.
Resolvin E3, 17,18-dihydroxy-5Z,8Z,11Z,13E,15E-eicosapentaenoic acid, is a potent anti-inflammatory lipid mediator. To determine the stereochemistries of the C17- and C18-hydroxy groups of resolvin E3 and to supply a sufficient amount of material for future biological studies, we developed a highly convergent and practical route to its four possible stereoisomers. The key reactions employed here were the Horner–Wadsworth–Emmons coupling, the two copper(I)-mediated reactions between the alkynes and the propargyl tosylates, and the simultaneous reduction of the three triple bonds to the three Z-olefins. 相似文献
778.
1,3-Diemthyl(5H,7H)imidazo(4,5-pyrimidine-2,4,6-trithione () was synthesized by the reaction of carbon disulfide with 1,3-dimethyl-4-cyano-5-aminoimidazolidine-2-thione () which was produced by reacting trimethylsilyl cyanide with methyl isothiocyanate followed by methanolysis. An unusual reversible formation of the dimethylamine salt of is also described. 相似文献
779.
A quantitative analysis of the polyamine in lung cancer patient fingernails by LC‐ESI‐MS/MS 下载免费PDF全文
Jun Zhe Min Akihito Matsumoto Gao Li Ying‐Zi Jiang Hai‐fu Yu Kenichiro Todoroki Koichi Inoue Toshimasa Toyo'oka 《Biomedical chromatography : BMC》2014,28(4):492-499
A quantitative analysis of polyamines in lung cancer patient fingernails by the combination of 4‐(N,N‐dimethylaminosulfonyl)‐7‐fluoro‐2,1,3‐benzoxadiazole derivatives and liquid chromatography–electrospray ionization tandem mass spectrometry is described. The reaction of the reagent with eight kinds of polyamines, that is, N1‐acetylputrescine (N1‐actPUT), N8‐acetylspermidine, N1‐acetylspermine, 1,3‐diaminopropane, putrescine (PUT), cadaverine, spermidine and spermine (SPM) effectively occurs at 60 °C for 30 min. The detection limits (signal‐to‐noise ratio 5) were 5–100 fmol. A good linearity was achieved from the calibration curves, which was obtained by plotting the peak area ratios of the analytes relative to the internal standard (IS), that is, 1,6‐diaminohexane, vs the injected amounts of polyamines (r2 > 0.996), and the intra‐day and inter‐day assay precisions were <9.84%. Furthermore, the recoveries (%) of the polyamines spiked in the human fingernails were 89.14–110.64. The present method was applied to human fingernail samples from 17 lung cancer patients and 39 healthy volunteers. The polyamine concentration was different based on the gender, that is, the N1‐actPUT and PUT contents were 3.10 times and 2.56 times higher in healthy men than in women, respectively. Additionally, in the lung cancer patient group, as compared with the healthy volunteers, the concentrations of SPM had a statistically significant (p < 0.05) correlation. Therefore, because the proposed method provides a good mass accuracy and the trace detection of the polyamines in human fingernails, this analytical technique could be a noninvasive technique to assist in the diagnosis and assessment of disease activity in lung cancer patients. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
780.