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671.
Zhang S Sakai R Abe T Iyoda T Norimatsu T Nagai K 《ACS applied materials & interfaces》2011,3(6):1902-1909
The visible-light-responsive photoelectrochemical and photocatalytic properties of nanoparticles of C(60), partially hydrolyzed aluminum phthalocyanine chloride (denoted as AlPc), and a composite of the two are reported. The three types of nanoparticles were obtained through a reprecipitation method from N-methyl-2-pyrrolidone solutions of C(60), aluminum phthalocyanine chloride (AlPcCl), and their mixture, respectively. The nanoparticle composite's ultraviolet-visible absorption, diffuse-reflectance and Fourier transform IR spectra, X-ray diffraction pattern, and scanning electron microscopy image are all similar to the sum of those of the C(60) and AlPc particles, respectively. The nano-ordered composite exhibits p/n junctionlike photoelectrochemical characteristics, which were investigated in comparison with those of vapor-deposited C(60) (n-type), AlPcCl (p-type), C(60)/AlPcCl (n/p), and AlPcCl/C(60) (p/n) electrodes. The nanoparticle composite further shows photocatalytic activity for the decomposition of trimethylamine to carbon dioxide in a suspension system. 相似文献
672.
In this paper, a low flicker-noise, 2.4 GHz direct onversion receiver (DCR) has been designed. A dynamic current injection (DCI) technique has been utilized in addition with a tuning inductor in the mixing stage. The tuning inductor has been replaced by a differential active inductor circuit, which gives the same inductance, with less chip size and high quality factor. The DCR has been designed in a TSMC 0.18 μm 1P6M CMOS process for wireless LAN 802.11g applications. The proposed DCR achieves 6.7 dB SSB-NF, 34 dB conversion gain, −13.5 dBm IIP3, and flicker noise (1/f) corner frequency of 30 kHz with 137.5 mW power consumption from 1.8 V supply voltage. 相似文献
673.
This paper presents the temperature dependence of predicting the flexural strength of a carbon fiber-reinforced sheet molding
compound (CF-SMC). First, three-point flexural tests were performed to measure strength and elastic modulus at a variety of
temperatures for CF-SMC specimens. Next, simple equations for predicting flexural strength were derived based on the fracture
mechanics approach. The predicted flexural strength was in reasonably good agreement with the experiment results. The scatter
of flexural strength was ascribed to the variation of location and size of the initial damage. In addition, the effect of
temperature on flexural strength and delamination behavior was explained in association with the temperature dependence of
the elastic modulus and fracture toughness. 相似文献
674.
Yoko Kitagawa Masahiro Okihashi Satoshi Takatori Keiji Kajimura Hirotaka Obana Masakazu Furuta Toshimasa Nishiyama 《Food Analytical Methods》2014,7(5):1066-1072
A rapid and simple method has been developed for the determination of 2-alkylcyclobutanone, 2-dodecylcyclobutanone (DCB), and 2-tetradecylcyclobutanone (TCB) in irradiated meat and processed foods. The procedure consists of extraction with n-hexane, following defatting and cleanup with a silica gel mini-column before gas chromatograph–mass spectrometry analysis. The method was evaluated using samples of beef, pork, Parmesan cheese, fried chicken, hamburger, gyoza (Chinese dumplings), and gyudon (boiled beef and onion seasoned with soy sauce and sugar). The recoveries of spiked DCB were 67–88 %, and those of TCB were 70–86 %. Furthermore, the method could detect DCB and TCB from samples irradiated at 1.0 and 2.6 kGy at levels dependent on dose; DCB and TCB were not detected in any nonirradiated samples. The method did not require special equipment, such as Soxhlet extraction, accelerated solvent extraction, or supercritical fluid extraction, for sample preparation. Thus, this method would be useful for determining DCB and TCB levels in irradiated meat and processed foods. 相似文献
675.
Enhancement of Stability and Activity of siRNA by Terminal Substitution with Serinol Nucleic Acid (SNA)
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Dr. Yukiko Kamiya Junya Takai Dr. Hiroshi Ito Keiji Murayama Dr. Hiromu Kashida Prof. Dr. Hiroyuki Asanuma 《Chembiochem : a European journal of chemical biology》2014,15(17):2549-2555
RNA interference (RNAi ), sequence‐specific gene silencing triggered by double‐stranded, small interfering RNA (siRNA), has become a facile and effective tool for biological research and holds potential for therapeutic applications. However, the application of siRNA is hindered by susceptibility to nucleases and off‐target effects. In this study, we introduced artificial nucleotides, serinol nucleic acid (SNA), with an acyclic scaffold, at the termini of siRNA strands. Our aim was appropriately to accommodate the antisense strand in an RNA‐induced silencing complex (RISC) by inhibiting sense‐strand incorporation and thus improve resistance to nuclease‐mediated degradation. Substitution of SNA into siRNA at both termini of the sense strand and at the 3′ terminus of the antisense strand improved antisense strand selectivity remarkably in the formation of RISC, RNAi activity, and nuclease resistance. 相似文献
676.
Development of a reduction-responsive amino acid that induces peptide bond cleavage in hypoxic cells
Shigenaga A Ogura K Hirakawa H Yamamoto J Ebisuno K Miyamoto L Ishizawa K Tsuchiya K Otaka A 《Chembiochem : a European journal of chemical biology》2012,13(7):968-971
Hypoxia-responsive amino acids are indispensable in the preparation of hypoxic tumor-specific peptidyl prodrugs. In this paper, the design and synthesis of a reduction-responsive amino acid that induces peptide bond cleavage after reduction of the nitro group are described. Application to hypoxia-responsive peptide bond cleavage system is also reported. 相似文献
677.
Keiji Komatsu Tetsuo Sekiya Ayumu Toyama Yasuhiro Hasebe Atsushi Nakamura Masahiro Noguchi Yu Li Shigeo Ohshio Hiroki Akasaka Hiroyuki Muramatsu Hidetoshi Saitoh 《Journal of Thermal Spray Technology》2014,23(5):833-838
R2O3 (R = Y, Eu, Er) metal oxides were synthesized from metal–ethylenediaminetetraacetic acid (EDTA) complexes using a flame spray technique. As this technique enables high deposition rates, films with thickness of several tens of micrometers were obtained. Films of yttria, europia, and erbia phase were synthesized on stainless-steel substrates with reaction assistance by H2–O2 combustion gas. The oxide films consisted of the desired crystalline phase with micropores. The porosity of the films was in the range of 6–15%, varying with the metal used. These results suggest that the true density of the metal oxide obtained from metal–EDTA powder through the thermal reaction process plays an important role in achieving film with the desired porosity. 相似文献
678.
We are presenting the first quantum chemical molecular dynamics (QM/MD) model simulations for iron catalyzed single-walled carbon nanotube (SWNT) growth based on the density functional tight binding (DFTB) quantum chemical potential. As model systems, open-ended (10,10) armchair tube fragments were selected with 0, 10, and 20 Fe atoms attached in 1,4-positions on the open rims, and ensembles of randomly oriented C2 molecules were included to simulate carbon plasma feedstock molecules. Isokinetic trajectories at 1500 K to 3000 K show that divalent Fe increases the number of coordination partners with carbon and/or Fe, depending on the Fe concentration. Fe/C interactions weaken the tube sidewall due to electron transfer from Fe into antibonding carbon orbitals, and C2 addition occurs mainly in an Fe-C2-Fe bridge addition mechanism, while growth of polyyne chains characteristic for high-temperature carbon systems is suppressed in the presence of Fe on the rims of the growing SWNT. Our findings are the first quantum chemical evidence for the importance of intermetallic interactions during SWNT growth. 相似文献
679.
Mesangial expansion and glomerular basement membrane (GBM) thickening were not different between normoalbuminuric (NA) and microalbuminuric (MA) type 2 diabetic patients. The quick-freezing and deep-etching (QF-DE) method allows us to examine three-dimensional ultrastructures of human renal glomeruli in vivo at high resolution. In the present study, the QF-DE method was applied to the renal biopsy from 6 type 2 diabetic patients without definable renal diseases other than diabetic nephropathy. Four patients were NA and the other two were MA. Three control specimens were normal parts in surgically resected kidneys of renal cell carcinoma. Replica membranes were prepared by the QF-DE method as previously described. By the QF-DE method, both GBM middle layer and mesangial matrix (MM) were composed of polygonal meshwork structures. The mesh pores of GBM and MM were more enlarged in size and irregular in shape in NA diabetic patients than those of the controls, and these ultrastructural changes became more obvious in MA patients. The diameters of mesh pores in the diabetic patients were significantly larger than those in the control subjects. In conclusion, the QF-DE method could be applied to needle renal biopsy and the present study has firstly clarified the difference of ultrastructural changes between NA and MA type 2 diabetic patients, which had not been disclosed by the conventional electron microscopy, were revealed by the QF-DE method. 相似文献
680.
Aiko Kawashima Ikuyo Tsukamoto Tomoko Koyabu Yasuko Murakami Takayo Kawakami Naoko Kakibuchi Kouichi Takaguchi Keiji Kita Misako Okita 《Lipids》2008,43(4):325-333
Eicosapentaenoic acid (EPA) (1.8 g/day) was administered to 12 chronic hepatitis C patients receiving combination therapy
of pegylated interferon (PEG-IFN) α-2b and ribavirin for 48 weeks (EPA group). Twelve patients were not administered EPA (control
group). All patients also received vitamin E and C (300, 600 mg/day, respectively) during the therapy. Serum alanine aminotransferase
improved to a normal level in 8 of 12 patients from the EPA group and 6 of 12 patients from the control group after 12 weeks.
Lymphocyte counts decreased significantly after 8 weeks in the control group, but not the EPA group. T-helper (Th) 1 decreased
after 4 weeks in the control group, but not in the EPA group (two-way ANOVA; P < 0.05). Th1/Th2 ratios were elevated in 9 of 12 patients in the EPA group, and 3 out of 12 in the control group (P < 0.05) after 8 weeks. After 12 weeks, the arachidonic acid/EPA molar ratio of erythrocyte membrane phospholipid correlated
negatively with the leukocyte count (n = 24, r = −0.439, P < 0.05) and the neutrophil count (n = 24, r = −0.671, P < 0.02). The hemoglobin level improved after 48 weeks compared with 24 weeks in only the EPA group. These findings suggest
that EPA supplementation may be useful in therapy for chronic hepatitis C. 相似文献