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961.
V. de Zea Bermudez S.M. Gomes Correia M.M. Silva S. Barros M.J. Smith R.A. Sá Ferreira L.D. Carlos C. Molina S.J.L. Ribeiro 《Journal of Sol-Gel Science and Technology》2003,26(1-3):375-381
Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and containing a wide concentration range of potassium triflate, KCF3SO3, have been analyzed by x-ray diffraction and differential scanning calorimetry. The pseudo-phase diagram proposed has been taken into account in the interpretation of the complex impedance measurements. The xerogels prepared are obtained as transparent, thin monoliths. At room temperature the highest conductivity found was 2 × 10–6 –1 cm–1. 相似文献
962.
Crespi M. S. Zorel H. E. Ribeiro C. A. 《Journal of Thermal Analysis and Calorimetry》2003,72(2):507-514
Ti(IV), Zr(IV) and Pb(II) complexes with 5-nitro-8-hydroxyquinoline (5-NQ) were obtained by precipitation in acetone/ammonium
solution medium. The compounds TiO(C9H5N2O3)2·;0.5H2O, ZrO(C9H5N2O3)2·2H2O and Pb(C9H5N2O3)2 were characterized by Elemental Analysis, X-ray Diffratometry and Infrared Absorption Spectrometry and their thermal behavior
followed by TG/DTA. This present study intends to show the variations in the thermal behavior of the compounds and in the
composition and/or structure of final oxide residues, in different atmospheres and heating rates.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
963.
DNA Intercalating RuII Polypyridyl Complexes as Effective Photosensitizers in Photodynamic Therapy 下载免费PDF全文
Cristina Mari Vanessa Pierroz Dr. Riccardo Rubbiani Dr. Malay Patra Jeannine Hess Priv.‐Doz. Dr. Bernhard Spingler Dr. Luciano Oehninger Julia Schur Prof. Dr. Ingo Ott Dr. Luca Salassa Priv.‐Doz. Dr. Stefano Ferrari Prof. Dr. Gilles Gasser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(44):14421-14436
Six substitutionally inert [RuII(bipy)2dppz]2+ derivatives (bipy=2,2′‐bipyridine, dppz=dipyrido[3,2‐a:2′,3′‐c]phenazine) bearing different functional groups on the dppz ligand [NH2 ( 1 ), OMe ( 2 ), OAc ( 3 ), OH ( 4 ), CH2OH ( 5 ), CH2Cl ( 6 )] were synthesized and studied as potential photosensitizers (PSs) in photodynamic therapy (PDT). As also confirmed by DFT calculations, all complexes showed promising 1O2 production quantum yields, well comparable with PSs available on the market. They can also efficiently intercalate into the DNA double helix, which is of high interest in view of DNA targeting. The cellular localization and uptake quantification of 1 – 6 were assessed by confocal microscopy and high‐resolution continuum source atomic absorption spectrometry. Compound 1 , and especially 2 , showed very good uptake in cervical cancer cells (HeLa) with preferential nuclear accumulation. None of the compounds studied was found to be cytotoxic in the dark on both HeLa cells and, interestingly, on noncancerous MRC‐5 cells (IC50>100 μM ). However, 1 and 2 showed very promising behavior with an increment of about 150 and 42 times, respectively, in their cytotoxicities upon light illumination at 420 nm in addition to a very good human plasma stability. As anticipated, the preferential nuclear accumulation of 1 and 2 and their very high DNA binding affinity resulted in very efficient DNA photocleavage, suggesting a DNA‐based mode of phototoxic action. 相似文献
964.
Michele Karoline Lima Daniela Martins Fernandes Marcela Fernandes Silva Mauro Luciano Baesso Antonio Medina Neto Gutierrez Rodriguês de Morais Celso Vataru Nakamura Angelo de Oliveira Caleare Ana Adelina Winkler Hechenleitner Edgardo Alfonso Gómez Pineda 《Journal of Sol-Gel Science and Technology》2014,72(2):301-309
Pure and Co-doped ZnO nanoparticles were synthesized with different cobalt levels (1–10 mol%) via adapted sol–gel method using water as solvent and characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy and photoacoustic absorption spectroscopy. The results showed that all the samples have hexagonal wurtzite structure, with no evidence of any secondary phases until 10 mol% of the dopant. The average crystallite size of the samples was in the range of 25–50 nm, do not showing significant differences with the increase of the dopant level. However, the band gap energy of the nanoparticles decreases from 2.98 eV (pure ZnO) to 1.95 eV (10 mol% of Co). The photocatalytic activity of the samples was evaluated on the removal of methylene blue under visible light irradiation, which revealed an efficiency reduction by Co-doping ZnO. The antibacterial property was carried out indicating activity of the prepared samples against gram-positive bacteria. 相似文献
965.
966.
967.
Kyung Ho Cho Orquidea Ribeiro Dr. Yang Du Dr. Elena Tikhonova Jonas S. Mortensen Kelsey Markham Dr. Parameswaran Hariharan Prof. Claus J. Loland Prof. Lan Guan Prof. Brian K. Kobilka Dr. Bernadette Byrne Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18833-18839
Detergents serve as useful tools for membrane protein structural and functional studies. Their amphipathic nature allows detergents to associate with the hydrophobic regions of membrane proteins whilst maintaining the proteins in aqueous solution. However, widely used conventional detergents are limited in their ability to maintain the structural integrity of membrane proteins and thus there are major efforts underway to develop novel agents with improved properties. We prepared mesitylene‐cored glucoside amphiphiles (MGAs) with three alkyl chains and compared these agents with previously developed xylene‐linked maltoside agents (XMAs) with two alkyl chains and a conventional detergent (DDM). When these agents were evaluated for four membrane proteins including a G protein‐coupled receptor (GPCR), some agents such as MGA‐C13 and MGA‐C14 resulted in markedly enhanced stability of membrane proteins compared to both DDM and the XMAs. This favourable behaviour is due likely to the increased hydrophobic density provided by the extra alkyl chain. Thus, this study not only describes new glucoside agents with potential for membrane protein research, but also introduces a new detergent design principle for future development. 相似文献
968.
969.
970.
Dr. Corrado Atzeri Prof. Luciano Marchiò Dr. Chun Y. Chow Dr. Jeff W. Kampf Prof. Vincent L. Pecoraro Dr. Matteo Tegoni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6482-6486
A 12‐metallacrown‐4 (MC) complex was designed and employed as the building block in the synthesis of coordination polymers, one of which is the first permanently porous MC architecture. The connection of the four‐fold symmetric MC subunits by CuII nodes led to the formation of 2D layers of metallacrowns. Channels are present in the crystalline architecture, which exhibits permanent porosity manifested in N2 and CO2 uptake capacity. 相似文献