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71.
A new type of ruthenium sensitizers JK-91 and JK-92 with a triazole moiety as a bridging group were designed and synthesized in an attempt to increase the π-conjugated system. Two compounds work as highly efficient sensitizers for the dye-sensitized nanocrystalline TiO2 solar cell. Under standard AM 1.5 sunlight, the sensitizer JK-91 yielded a short-circuit photocurrent density of 12.55 mA/cm2, an open-circuit voltage of 0.73 V, and a fill factor of 0.73, corresponding to an overall conversion efficiency of 6.75%. 相似文献
72.
We present a new fabrication scheme for 3D-networked, cylindrical microfluidic (MF) channels based on shaping, bonding, and assembly of sucrose fibers. It is a simple, cleanroom-free, and environment-friendly method, ideal for rapid prototyping of lab-on-a-chip devices. Despite its simplicity, it can realize complex 3D MF channel architectures such as cylindrical tapers, internal loops, end-to-side junctions, tapered junctions, and stenosis. The last two will be of special use for realizing vaso-mimetic MF structures. It also enables molding with polymers incompatible with high-temperature processing. 相似文献
73.
Young-Geun Han Won-Taek Han Byeong Ha Lee Un-Chul Paek Youngjoo Chung Chang-Seok Kim 《Fiber and Integrated Optics》2001,20(6):591-600
We will present in this work the quantitative analysis of the relationship between the doping concentrations of GeO 2 and B 2 O 3 in the core and cladding regions and the temperature sensitivity of the resonance wavelength shift in long-period fiber gratings (LPFGs). Based on this analysis, the temperature sensitivity was suppressed and enhanced to 0.002 nm/°C and 0.28 nm/°C, respectively. We will also discuss the effect of the residual mechanical stress on the optical and mechanical properties of LPFGs. In particular, we will present the measurement results of the dependence of the refractive index change and mechanical strength on the residual mechanical stress in the boron-doped fibers with depressed clad and matched clad. 相似文献
74.
Xi-Hua Cui Hosakatte Niranjana Murthy Kee-Yoeup Paek 《Applied biochemistry and biotechnology》2014,174(2):784-792
Hypericum perforatum L. (St. John’s Wort) is an important medicinal plant which is widely used in the treatment for depression and irritable bowel syndrome. It is also used as a dietary supplement. Major bioactive phytochemicals of H. perforatum are phenolics and flavonoids. Quality of these phytochemicals is dramatically influenced by environmental and biological factors in the field grown plants. As an alternative, we have developed adventitious root cultures in large-scale bioreactors for the production of useful phytochemicals. Adventitious roots of H. perforatum were cultured in 500 l pilot-scale airlift bioreactors using half-strength Murashige and Skoog medium with an ammonium and nitrate ratio of 5:25 mM and supplemented with 1.0 mg l?1 indole butyric acid, 0.1 mg l?1 kinetin, and 3 % sucrose for the production of bioactive phenolics and flavonoids. Then 4.6 and 6.3 kg dry biomass were realized in the 500 l each of drum-type and balloon-type bioreactors, respectively. Accumulation of 66.9 mg g?1 DW of total phenolics, 48.6 mg g?1 DW of total flavonoids, 1.3 mg g?1 DW of chlorogenic acid, 0.01 mg g?1 DW of hyperin, 0.04 mg g?1 DW of hypericin, and 0.01 mg g?1 DW of quercetin could be achieved with adventitious roots cultured in 500 l balloon-type airlift bioreactors. Our findings demonstrate the possibilities of using H. perforatum adventitious root cultures for the production of useful phytochemicals to meet the demand of pharmaceutical and food industry. 相似文献
75.
Highly Reactive Nonheme Iron(III) Iodosylarene Complexes in Alkane Hydroxylation and Sulfoxidation Reactions
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Dr. Seungwoo Hong Dr. Bin Wang Dr. Mi Sook Seo Dr. Yong‐Min Lee Myoung Jin Kim Prof. Dr. Hyung Rok Kim Prof. Dr. Takashi Ogura Dr. Ricardo Garcia‐Serres Dr. Martin Clémancey Prof. Dr. Jean‐Marc Latour Prof. Dr. Wonwoo Nam 《Angewandte Chemie (International ed. in English)》2014,53(25):6388-6392
High‐spin iron(III) iodosylarene complexes bearing an N‐methylated cyclam ligand are synthesized and characterized using various spectroscopic methods. The nonheme high‐spin iron(III) iodosylarene intermediates are highly reactive oxidants capable of activating strong C? H bonds of alkanes; the reactivity of the iron(III) iodosylarene intermediates is much greater than that of the corresponding iron(IV) oxo complex. The electrophilic character of the iron(III) iodosylarene complexes is demonstrated in sulfoxidation reactions. 相似文献
76.
Jang H. C. Sin K. R. Paek H. R. Jang Y. M. Jong S. H. 《Russian Journal of Organic Chemistry》2020,56(12):2228-2235
Russian Journal of Organic Chemistry - N-Aryl-substituted pyrrolidine derivatives were synthesized via tributylphosphine-catalyzed sequential Michael addition of α-aminonitriles and methyl... 相似文献
77.
78.
We propose a co-sintering process for effective fabrication of three-layered structure for direct-write planar waveguide. Processing parameters and optical properties of the waveguide was investigated. 相似文献
79.
Hong S Lee YM Cho KB Sundaravel K Cho J Kim MJ Shin W Nam W 《Journal of the American Chemical Society》2011,133(31):11876-11879
Mononuclear nonheme iron(IV)-oxo complexes with two different topologies, cis-α-[Fe(IV)(O)(BQCN)](2+) and cis-β-[Fe(IV)(O)(BQCN)](2+), were synthesized and characterized with various spectroscopic methods. The effect of ligand topology on the reactivities of nonheme iron(IV)-oxo complexes was investigated in C-H bond activation and oxygen atom-transfer reactions; cis-α-[Fe(IV)(O)(BQCN)](2+) was more reactive than cis-β-[Fe(IV)(O)(BQCN)](2+) in the oxidation reactions. The reactivity difference between the cis-α and cis-β isomers of [Fe(IV)(O)(BQCN)](2+) was rationalized with the Fe(IV/III) redox potentials of the iron(IV)-oxo complexes: the Fe(IV/III) redox potential of the cis-α isomer was 0.11 V higher than that of the cis-β isomer. 相似文献
80.
Most immuno-analytical systems employ antibodies that do not readily dissociate upon binding to its partner antigen (i.e., target analyte; α2-macroglobulin as a model) and, thus, either need to be disposed of after one-time use or be reused after binding has been reset. To achieve a minimum-step analysis, an antibody that is capable of rapidly reversible binding with high affinity to an antigen was investigated in this study. This antibody was immobilized on the surface of a label-free sensor, which was combined with microfluidic channels, to demonstrate its applicability. The antibody was successively reused without a regeneration step under physiological conditions, offered specific analysis in the serum medium, and detected the analyte at concentrations as low as 0.1 ng mL(-1), which could further be enhanced by 100-fold. The sensor response reached 95% equilibrium after 8.3 and 14.9 min in average on each dose level for the concentration increase and decrease, respectively. The dynamic range covered a 5 logarithmic analyte concentration. Since the sampling size was in the nanolitre to millilitre range per day under the conditions used and the sensor may retain a long shelf-life, it could potentially be used in a clinical setting for long-term, on-line monitoring of diseases. 相似文献