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231.
Spherical activated carbon derived from spherical cellulose and its performance as EDLC electrode
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Spherical activated carbons (ca. 30–100 μm in diameter) were synthesized from commercial spherical cellulose beads. The addition of guanidine phosphate was performed as the pretreatment, and CO2 activation was applied for enhancing the specific surface area. The addition of guanidine phosphate drastically improved the yield of carbon during the activation process. The specific surface area reached 1545 m2 g?1 for the sample heat‐treated at 850°C for 1 h in flowing N2 and continuously for 3 h in flowing CO2 activation. The calculated capacitance values per area (F m?2) for the pore size of less than 1 nm was large in the case of small current density. The distortion of the solvation shell could be the reason for the large capacitance value for the small pore size of less than 1 nm. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40950. 相似文献
232.
A Coenzyme‐Independent Decarboxylase/Oxygenase Cascade for the Efficient Synthesis of Vanillin
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Dr. Toshiki Furuya Misa Miura Prof. Dr. Kuniki Kino 《Chembiochem : a European journal of chemical biology》2014,15(15):2248-2254
Vanillin is one of the most widely used flavor compounds in the world as well as a promising versatile building block. The biotechnological production of vanillin from plant‐derived ferulic acid has attracted much attention as a new alternative to chemical synthesis. One limitation of the known metabolic pathway to vanillin is its requirement for expensive coenzymes. Here, we developed a novel route to vanillin from ferulic acid that does not require any coenzymes. This artificial pathway consists of a coenzyme‐independent decarboxylase and a coenzyme‐independent oxygenase. When Escherichia coli cells harboring the decarboxylase/oxygenase cascade were incubated with ferulic acid, the cells efficiently synthesized vanillin (8.0 mM , 1.2 g L ?1) via 4‐vinylguaiacol in one pot, without the generation of any detectable aromatic by‐products. The efficient method described here might be applicable to the synthesis of other high‐value chemicals from plant‐derived aromatics. 相似文献
233.
Takeuchi A Ohtsuki C Kamitakahara M Ogata S Miyazaki T Tanihara M 《Journal of materials science. Materials in medicine》2008,19(1):387-393
Deposition of a hydroxyapatite layer with similar structure to bone mineral is an attractive approach to the fabrication of
bioactive coating layers to achieve direct bonding to living bone. To get successful coating of a hydroxyapatite layer on
an organic polymer using a biomimetic solution, it is essential to find organic substrates that can effectively induce heterogeneous
nucleation of hydroxyapatite after exposure to the body environment. Our previous study showed that sericin, a type of silk
protein, has the ability to induce hydroxyapatite nucleation in a biomimetic solution when the sericin has a β sheet structure.
To confirm the effectiveness of the β sheet structure in hydroxyapatite nucleation, we focused on investigating hydroxyapatite
deposition on a synthetic polypeptide with a β sheet structure in a biomimetic solution. The β sheet forming polypeptides
with and without carboxyl groups, poly(FE)3FG, poly(FQ)3FG, poly(LE)3LG and poly(LQ)3LG, were synthesized in this study. All the polypeptides had mainly β sheet structure. After soaking the polypeptide films
in 1.5SBF, which has 1.5 times the inorganic ion concentrations of human blood plasma, hydroxyapatite formed on the surfaces
of the polypeptides with carboxyl groups, poly(FE)3FG and poly(LE)3LG, within 2 days, but not on those without carboxyl groups, poly(FQ)3FG and poly(LQ)3LG. We confirmed that the β sheet structure was effective for hydroxyapatite nucleation even in the synthetic polypeptide.
This finding is useful for the future design of organic polymers that can effectively induce nucleation of hydroxyapatite. 相似文献
234.
Hiroshi Okuda Toshiki Horiuchi Toshiki Maruyama Michiaki Yamasaki Yoshihito Kawamura Koji Hagihara Shinji Kohara 《Metallurgical and Materials Transactions A》2014,45(1):147-151
Development of LPSO structure and in-plane ordering during annealing the Mg85Y9Zn ternary alloy sample at 673 K (400 °C) was examined by synchrotron radiation small-angle scattering/diffraction measurements. By examining the first diffraction peaks for 18R, 10H, and in-plane order spot, the growth kinetics of in-plane order domain and the transition from 10H into 18R were discussed. The domain growth of in-plane order was characterized by small domain with little correlation between neighboring segregation layers. 相似文献
235.
Kihara T 《Applied optics》2006,45(35):8848-8854
In scattered-light photoelasticity with unpolarized light, the secondary principal stress direction psi and the relative phase retardation rho in a three-dimensional stressed model with rotation of the principal stress axes can be obtained by use of Stokes parameters. For completely automated stress analysis, measurements of the total relative phase retardation and the secondary principal stress direction over the entire field are required, and it is necessary to unwrap psi and rho. A phase unwrapping method is thus proposed for the determination of these values based on scattered-light photoelasticity. The values are easily obtained via an arctangent function, overcoming the error associated with the quarter-wave plate by employing an incident light of different wavelengths. The proposed technique provides automated and nondestructive determination of the total relative phase retardation and the secondary principal stress direction in a model exhibiting rotation of the principal stress axes. 相似文献
236.
T Watanabe Y Kawano S Kanamaru T Onishi S Kaneko Y Wakata R Nakagawa A Makimoto Y Kuroda Y Takaue JE Talmadge 《Canadian Metallurgical Quarterly》1999,93(4):1157-1163
The relationship between stem cell mobilization with granulocyte colony-stimulating factor (G-CSF) and the endogenous production of interleukin-8 (IL-8), macrophage inflammatory protein-1alpha (MIP-1alpha), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) was studied in normal donors for allogeneic peripheral blood stem cell (PBSC) transplantation. G-CSF was administered to 20 normal donors at a dose of 10 microg/kg/d for 5 days with aphereses on days 5 and 6 of G-CSF treatment. Cytokine serum levels were measured using an enzyme-linked immunosorbent assay (ELISA) before and during G-CSF treatment. Before treatment, the average level of IL-8 was 7.1 pg/mL, increasing to 207.0 pg/mL on day 5 and 189.1 pg/mL on day 6. Serum IL-8 levels correlated CD34(+) cell numbers (P =.0151 and P =.0005 on days 5 and 6, respectively) and colony-forming unit-granulocyte-macrophage (CFU-GM) numbers (P =.0019 and P =.0010 on days 5 and 6, respectively). Furthermore, preapheresis serum IL-8 levels correlated with the yield of CD34(+) cells (P =.0027). In contrast, before treatment, the average levels of MIP-1alpha, TNF-alpha, and IFN-gamma were 70.1, 4.03, and 3.84 pg/mL, respectively, and no significant changes in the levels of these cytokines were observed during G-CSF treatment. These studies suggest that IL-8 production may be critical to G-CSF-induced stem cell mobilization, although the underlying mechanism could not be clarified. 相似文献
237.
Toshiki Ueno Takeru Nakaki Taisei Mukogawa Shuonan Dong Hiroki Kurita Keisuke Otsuka Kanjuro Makihara Fumio Narita 《Advanced Engineering Materials》2023,25(19):2300185
In this study, the Fe–Co alloy is combined with cobalt ferrite (CoFe2O4) and nickel (Ni) to form Fe–Co/CoFe2O4 and Fe–Co/Ni clad sheets and their energy-harvesting performance is evaluated. The Fe–Co/CoFe2O4 clad sheet exhibits an output voltage of 4.229 mV and an output power of 6.89 nW at a wind speed of 10 m s−1. The energy-harvesting performance of both these clad sheets cannot be quantitatively compared owing to their different thicknesses, which result in varying volume and distance from the neutral plane. Nevertheless, the values of output voltage and power for Fe–Co/CoFe2O4 are higher than those for Fe–Co/Ni (2.107 mV and 0.294 nW). 相似文献
238.
Koji Kadota Toshiki Mikami Dr. Ai Kohata Dr. Jumpei Morimoto Prof. Dr. Shinsuke Sando Dr. Kohsuke Aikawa Dr. Takashi Okazoe 《Chembiochem : a European journal of chemical biology》2023,24(21):e202300374
With an increasing demand for macromolecular biotherapeutics, the issue of their poor cell-penetrating abilities requires viable and relevant solutions. Herein, we report tripeptides bearing an amino acid with a perfluoroalkyl (RF) group adjacent to the α-carbon. RF-containing tripeptides were synthesized and evaluated for their ability to transport a conjugated hydrophilic dye (Alexa Fluor 647) into the cells. RF-containing tripeptides with the fluorophore showed high cellular uptake efficiency and none of them were cytotoxic. Interestingly, we demonstrated that the absolute configuration of perfluoroalkylated amino acids (RF-AAs) affects not only nanoparticle formation but also the cell permeability of the tripeptides. These novel RF-containing tripeptides are potentially useful as short and noncationic cell-penetrating peptides (CPPs). 相似文献