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991.
Hyunji Jung Dr. Abhishek Dubey Hyun Jung Koo Dr. Vaishali Vajpayee Dr. Timothy R. Cook Dr. Hyunuk Kim Prof. Se Chan Kang Prof. Peter J. Stang Prof. Ki‐Whan Chi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6709-6717
The synthesis of six new [2+2] metallarectangles through the coordination‐driven self‐assembly of octahedral RuII‐based acceptors with ambidentate pyridyl‐carboxylate donors is described. These molecular rectangles are fully characterized by 1H NMR spectroscopy, high‐resolution electrospray mass spectrometry, and single‐crystal X‐ray diffraction. In each case, despite the possible formation of multiple isomers, based on the relative orientation of the pyridyl and carboxylate groups (head‐to‐head versus head‐to‐tail), evidence for the formation of a single preferred ensemble (head‐to‐tail) was found in the 1H NMR spectra. Furthermore, the cytotoxicities of all of the rectangles were established against A549 (lung), AGS (gastric), HCT‐15 (colon), and SK hep 1 (liver) human cancer cell lines. The cytotoxicities of rectangles that contained the 5,8‐dihydroxy‐1,4‐naphthaquinonato bridging moiety between the Ru centers ( 9 – 11 ) were particularly high against AGS cancer cells, with IC50 values that were comparable to that of reference drug cisplatin. 相似文献
992.
Seung Jun Chang Hyun Soo Chung David Skoug 《Central European Journal of Mathematics》2013,11(3):538-551
In this paper we obtain several basic formulas for generalized integral transforms, convolution products, first variations and inverse integral transforms of functionals defined on function space. 相似文献
993.
Hyun Kyoo Park Hana Rah Dong Jun Kang Uong Chun Sun-Geon Kim 《Journal of Sol-Gel Science and Technology》2013,67(3):464-472
Nanostructures of single crystallites of spinel LiMn2O4 (LMO) were prepared by the simple pyrolysis of aqueous solution of LiNO3 and Mn(NO3)2 in a confined space such as either droplets or mesopores. When the mixed nitrate solution was spray pyrolyzed at temperatures below 700 °C, 1-μm LMO spheres were obtained consisting of ~20-nm single crystallites randomly packed. Such LMO phase, once obtained, would sustain for further heat-treatment. Next, new spraying solution was prepared by adding the precursor for mesoporous silica (MPS) to the nitrates solution. By spray pyrolyzing such solution, LMO was impregnated inside pores of the MPS being structured. The silica could be removed by subsequent NaOH treatment to leave spherical LMO mesophase. The nitrates was also able to soak into the existing MPS having cylindrical pores and form short isolated LMO chains in the mesopores by the subsequent heating. After the same NaOH treatment, the LMO phase turned into bundles of very ‘long’, and often straight, chains, consisting of 8-nm LMO nanoparticles. This will be elucidated through further study. 相似文献
994.
Biomineralized Multifunctional Magnetite/Carbon Microspheres for Applications in Li‐Ion Batteries and Water Treatment
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Dr. Hyun‐Woo Shim Dr. Sangbaek Park Hee Jo Song Jae‐Chan Kim Eunjin Jang Prof. Kug Sun Hong Prof. T. Doohun Kim Prof. Dong‐Wan Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4655-4663
Advanced functional materials incorporating well‐defined multiscale architectures are a key focus for multiple nanotechnological applications. However, strategies for developing such materials, including nanostructuring, nano‐/microcombination, hybridization, and so on, are still being developed. Here, we report a facile, scalable biomineralization process in which Micrococcus lylae bacteria are used as soft templates to synthesize 3D hierarchically structured magnetite (Fe3O4) microspheres for use as Li‐ion battery anode materials and in water treatment applications. Self‐assembled Fe3O4 microspheres with flower‐like morphologies are systematically fabricated from biomineralized 2D FeO(OH) nanoflakes at room temperature and are subsequently subjected to post‐annealing at 400 °C. In particular, because of their mesoporous properties with a hollow interior and the improved electrical conductivity resulting from the carbonized bacterial templates, the Fe3O4 microspheres obtained by calcining the FeO(OH) in Ar exhibit enhanced cycle stability and rate capability as Li‐ion battery anodes, as well as superior adsorption of organic pollutants and toxic heavy metals. 相似文献
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997.
Montelukast (MKT), a leukotriene receptor antagonist, degrades when it is exposed to light. The analysis of MKT content in blood plasma by high-pressure liquid chromatography requires several sample preparation steps including deproteinization. This study aimed to evaluate MKT photodegradation in blood plasma samples and optimize a deproteinization method to reduce MKT photodegradation, and thereby improve analytical quality. We evaluated the stability of MKT in water and plasma in real time using high-pressure liquid chromatography and optimized a sample deproteinization procedure by comparing the effectiveness of several deproteinization methods. When exposed to light, MKT photodegraded quickly. Although MKT photodegradation was slightly slower than that in water, a half portion (55%) of the MKT in plasma degraded within 2 h when exposed to light. The rate of MKT photodegradation was dramatically reduced by sample deproteinization using ZnSO4–Ba(OH)2, but it was accelerated by deproteinization through precipitation using methanol or acetonitrile. These results suggest that precautions should be taken when preparing plasma samples for the analysis of MKT, and that deproteinization of such samples using ZnSO4–Ba(OH)2 can reduce the risk of analytical error arising from MKT photodegradation. 相似文献
998.
Novel stilbene‐based Fischer base analog of leuco‐TAM – (2E,2′Z)‐{2‐(4‐(E)‐styrylphenyl)propane‐1,3‐diylidene}bis(1,3,3‐trimethylindoline) – derivatives: synthesis and structural consideration by 1D NMR and 2D NMR spectroscopy
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We report the synthesis of a series of novel stilbene‐based (St) Fischer base analogs of leuco‐triarylmethane (LTAM) dyes by treating Fischer base with (E)‐4‐styrylbenzaldehyde derivatives. All St‐LTAM molecules examined herein are characterized by 1D and 2D NMR. They were found to exhibit ZE configuration and isomerize to their diastereomers EE and ZZ in 2–3 h. They exhibit type I behavior of diastereomeric isomerization. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
This study aims at analyzing the red blood cell (RBC) deformation and velocity while streaming through venules and through capillaries whose diameters are smaller than the RBC size. The characteristics of the RBC shape change and velocity can potentially help in diagnosing diseases. In this work, the RBC is considered as a surfactant‐covered droplet. This is justified by the fact that the cell membrane liquefies under pressure in the capillaries, and this allows the marginalization of its mechanical properties. The RBC membrane is in fact a macro‐colloid containing lipid surfactant. When liquefied, it can be considered as a droplet of immiscible hemoglobin covered with lipid surfactant in a plasma surrounding. The local gradient in the surface tension due to non‐uniform local interface surfactant distribution is neglected here, and a non‐uniform zonal‐averaged value of surface tension representative of the surfactant bulk zonal concentration is rather implemented. The interplay between the surface tension geometry and the hydrodynamic conditions determines the droplet shape by affecting a change in its Weber number, and influences its velocity. The Gunstensen lattice Boltzmann model for immiscible fluids is used here since it provides independent adjustment of the local surface tension, and allows the use of fluids with viscosity contrast. The proposed concept was used to investigate the dynamic shape change of the RBC while flowing through the microvasculature, and to explore the Fahraeus and the Fahraeus–Lindqvist effects. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
1000.