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911.
912.
Kim KJ Choi HY Hwang SH Park YS Kwueon EK Choi DS Song CE 《Chemical communications (Cambridge, England)》2005,(26):3337-3339
Markedly enhanced recyclability of osmium catalyst in asymmetric dihydroxylation has been achieved by using osmylated macroporous resins bearing both residual vinyl groups and quaternary ammonium moiety. 相似文献
913.
Soon-Gil Jung W.K. Seong W.N. Kang Eun-Mi Choi Heon-Jung Kim Sung-Ik Lee Hyeong-Jin Kim H.C. Kim 《Physica C: Superconductivity and its Applications》2006,450(1-2):114-117
The Hall resistivity (ρxy) and the longitudinal resistivity (ρxx) in c-axis-oriented superconducting MgB2 thin films have been investigated in extended fields up to 18 T. We have observed a scaling behavior between the Hall resistivity and the longitudinal resistivity, , where the exponent (β) is observed to be independent of the temperatures and the magnetic fields. For a wide magnetic field region from 1 to 18 T and a wide temperature region from 10 to 28 K, a universal power law with β = 2.0 ± 0.1 was observed in c-axis-oriented MgB2 thin films. These results can be well interpreted by using recent models. 相似文献
914.
Seong Kim Patricia M. Cotts Willi Volksen 《Journal of Polymer Science.Polymer Physics》1992,30(2):177-183
The recent introduction of multiangle light-scattering detectors for size-exclusion chromatography has made possible the measurement of the root mean square radius of gyration (Rg) and molecular weight (M) of polymer fractions eluting from a size-exclusion chromatography column. The characterization of the dimensions of a polymer may be accomplished with only a few milligrams. The dimensions of a polyimide precursor prepared by the condensation of the meta-diethyl ester of pyromellitic dianhydride with para-phenylene diamine have been measured with this technique. The dependence of Rg on M across the distribution is compared with that predicted for a freely rotating chain, and with other similar polymers measured with hydrodynamic techniques. 相似文献
915.
We have enhanced color-rendering property of a blue light emitting diode (LED) pumped white LED with yellow emitting Y3Al5O12:Ce3+ (YAG:Ce) phosphor using addition of Pr and Tb as a co-activator and host lattice element, respectively. Pr3+ addition to YAG:Ce phosphor resulted in sharp emission peak at about 610 nm through 1D2→3H4 transition. And when Tb3+ substituted Y3+ sites, Ce3+ emission band shifted to a longer wavelength due to larger crystal field splitting. Y3Al5O12:Ce3+, Pr3+ and (Y1−xTbx)3Al5O12:Ce3+ phosphors were coated on blue LEDs to fabricate white LEDs, respectively, and their color-rendering indices (CRIs, Ra) were measured. As a consequence of the addition of Pr3+ or Tb3+, CRI of the white LEDs improved to be Ra=83 and 80, respectively. Especially, blue LED pumped (Y0.2Tb0.8)3Al5O12:Ce3+ white LED showed both strong luminescence and high color-rendering property. 相似文献
916.
In this article, we consider the global existence and decay rates of solutions for the transmission problem of Kirchhoff type wave equations consisting of two physically different types of materials, one component being a Kirchhoff type wave equation with time dependent localized dissipation which is effective only on a neighborhood of certain part of boundary, while the other being a Kirchhoff type viscoelastic wave equation with nonlinear memory. 相似文献
917.
Ha-Yeon Song Jeong Moo Han Eui-Hong Byun Woo Sik Kim Ho Seong Seo Eui-Baek Byun 《Molecules (Basel, Switzerland)》2021,26(2)
Bombyx batryticatus, a protein-rich edible insect, is widely used as a traditional medicine in China. Several pharmacological studies have reported the anticancer activity of B. batryticatus extracts; however, the capacity of B. batryticatus extracts as immune potentiators for increasing the efficacy of cancer immunotherapy is still unverified. In the present study, we investigated the immunomodulatory role of B. batryticatus protein-rich extract (BBPE) in bone marrow-derived dendritic cells (BMDCs) and DC vaccine-immunized mice. BBPE-treated BMDCs displayed characteristics of mature immune status, including high expression of surface molecules (CD80, CD86, major histocompatibility complex (MHC)-I, and MHC-II), increased production of proinflammatory cytokines (tumor necrosis factor-α and interleukin-12p70), enhanced antigen-presenting ability, and reduced endocytosis. BBPE-treated BMDCs promoted naive CD4+ and CD8+ T-cell proliferation and activation. Furthermore, BBPE/ovalbumin (OVA)-pulsed DC-immunized mice showed a stronger OVA-specific multifunctional T-cell response in CD4+ and CD8+ T cells and a stronger Th1 antibody response than mice receiving differently treated DCs, which showed the enhanced protective effect against tumor growth in E.G7 tumor-bearing mice. Our data demonstrate that BBPE can be a novel immune potentiator for a DC-based vaccine in anticancer therapy. 相似文献
918.
Yu GR Kim SH Park SH Cui XD Xu DY Yu HC Cho BH Yeom YI Kim SS Kim SB Chu IS Kim DG 《Experimental & molecular medicine》2007,39(5):641-652
The aim of this study was to identify molecular markers associated with oncogenic differentiation in hepatocellular carcinoma (HCC). Using an unsupervised clustering method with a cDNA microarray, HCC (T) gene expression profiles and corresponding non-tumor tissues (NT) from 40 patients were analyzed. Of total 217 genes, 72 were expressed preferentially in HCC tissues. Among 186 differentially regulated genes, there were molecular chaperone and tumor suppressor gene clusters in the Edmondson grades I and II (GI/II) subclass compared with the liver cirrhosis (LC) subclass. The Edmondson grades III and IV (GIII/IV) subclass with a poor survival (P=0.0133) contained 122 differentially regulated genes with a cluster containing various metastasis- and invasion-related genes compared with the GI/II subclass. Immunohistochemical analysis revealed that ANXA2, one of the 72 genes preferentially expressed in HCC, was over-expressed in the sinusoidal endothelium and in malignant hepatocytes in HCC. The genes identified in the HCC subclasses will be useful molecular markers for the genesis and progression of HCC. In addition, ANXA2 might be a novel marker for tumor angiogenesis in HCC. 相似文献
919.
The decomposition and detoxification of compounds are of great interest in environmental protection and defense-related areas. We report the generation of gaseous excited species by scanning atmospheric radio frequency (rf) plasma and their reactions with two representative organophosphorus nerve agents, paraoxon and parathion, deposited on solid surfaces. The excited gaseous species generated in the Ar and Ar/O2 plasma were identified as atomic oxygen, OH radical, and excited nitrogen molecule from optical emission spectroscopy analysis. The reaction of these species with paraoxon and parathion was monitored with reflection-absorption infrared spectroscopy and compared with the decomposition by UV irradiation and UV/ozone treatments. The decomposition products of the atmospheric rf plasma treatment were similar to those of the UV/ozone treatment. The atomic oxygen and excited OH species generated by the plasma appear to be responsible for the oxidation of paraoxon and parathion. The plasma-induced decomposition process was much faster and more efficient than the UV/ozone process. The complete detoxification of paraoxon and parathion upon a short time exposure to the Ar/O2 plasma was confirmed by the Drosophila melanogaster culture test. 相似文献
920.
The magnitude of the capillary force at any given temperature and adsorbate partial pressure depends primarily on four factors: the surface tension of the adsorbate, its liquid molar volume, its isothermal behavior, and the contact geometry. At large contacting radii, the adsorbate surface tension and the contact geometry are dominating. This is the case of surface force apparatus measurements and atomic force microscopy (AFM) experiments with micrometer-size spheres. However, as the size of contacting asperities decreases to the nanoscale as in AFM experiments with sharp tips, the molar volume and isotherm of the adsorbate become very important to capillary formation as well as capillary adhesion. This effect is experimentally and theoretically explored with simple alcohol molecules (ethanol, 1-butanol, and 1-pentanol) which have comparable surface tensions but differing liquid molar volumes. Adsorption isotherms for these alcohols on silicon oxide are also reported. 相似文献