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101.
We report the infrared (IR) response of Cu-O chains in the high-T(c) superconductor YBa(2)Cu(3)O(y) over the doping range spanning y=6.28-6.75. We find evidence for a power law scaling at mid-IR frequencies consistent with predictions for Tomonaga-Luttinger liquid, thus supporting the notion of one-dimensional transport in the chains. We analyze the role of coupling to the CuO2 planes in establishing metallicity and superconductivity in disordered chain fragments. 相似文献
102.
H Yoshida K Uno S Minoshima K Imazeki T Miyoshi M Saitou H Akiba N Arimizu 《Radioisotopes》1989,38(8):347-350
The biodistribution of nanometer-sized colloidal particles (nanocolloids, Solco-Basle Ltd.) was examined in six rabbits with turpentine-induced abscesses in the musculature of their hind legs. 99mTc labelled colloids with a mean particle size less than 100 nm were administered to each rabbit intravenously. The biodistribution of the tracer was studied with a gamma camera 1, 3, and 24 hours after injection. Prominent uptakes were demonstrated in the liver, spleen, bone marrow, kidneys, and urinary bladder. On the other hand, the abscess and surrounding inflammatory edema were depicted as unclearly margined faint hot spots. Subsequently, the rabbits were sacrificed and activity per gram tissues were counted with a well-type gamma counter. Although the results were almost in agreement with a gamma camera study, it was noticed the activity counts in the abscess were significantly higher than that of control muscles. 相似文献
103.
104.
Sang-Hwui Hong Makoto Mikami Kouji Mimura Masahito Uchikoshi Akihiko Yasuo Seishi Abe Katashi Masumoto Minoru Isshiki 《Journal of Crystal Growth》2009,311(14):3609-3612
The high-quality ZnO single crystals were grown by seeded chemical vapor transport (CVT) in a newly designed ampoule using carbon as a transport agent. The well-faceted crystal of about 5×5×5 mm3 can be grown reproducibly. Secondary ion mass spectroscopy (SIMS) analysis, X-ray rocking curve (XRC) and photoluminescence (PL) measurements demonstrate that the grown single crystal is of high purity and high crystallinity. 相似文献
105.
Michio Sorai Shigemi Murkawa Kouji Ogasahara Hiroshi Suga 《Chemical physics letters》1980,76(3):510-514
Laser Raman spectra of ferrocene crystal are recorded for the stable (orthorhombic) and metastable (triclinic) low-temperature phases, and the stable and undercooled (monoclinic) high-temperature phases.The skeletal vibrational modes [v4(A1g) and v16(E1g)], the CH bending (⊥e) mode [v25(E2g)], and the lattice modes below 100 cm?1 show characteristic changes among these phases. 相似文献
106.
A further improvement of electrokinetic supercharging (EKS) methodology has been proposed, with the objective to enhance the sensitivity of the conventional CZE-UV method down to a single-digit part per trillion (ppt) level. The advanced EKS procedure is based on a novel phenomenon displaying the formation of a zone with an increased concentration of the hydrogen ion, capable to perform the function of a terminator, behind the sample zone upon electrokinetic injection. In combination with a visualizing co-ion of BGE, protonated 4-methylbenzylamine, acting as the leading ion, such system-induced terminator a effected the transient ITP state to efficiently concentrate cationic analytes prior to CZE. Furthermore, to amass more analyte ions within the effective electric field at the injection stage, a standard sample vial was replaced with an elongated vial that allowed the sample volume to be increased from 500 to 900 μL. Alongside, this replacement made the upright distance between the electrode and the capillary tips prolonged to 40.0 mm to achieve high-efficiency electrokinetic injection. The computer simulation was used for profiling analyte concentration, pH, and field strength in order to delineate formation of the terminator during sample injection. The proposed preconcentration strategy afforded an enrichment factor of 80,000 and thereby the LODs of rare-earth metal ions at the ppt level, e.g. 0.04 nM (6.7 ng/L) for erbium(III). 相似文献
107.
108.
The concentration of Fe(II) ion is determined by chelation with 2-nitroso-5-diehtylaminophenol and liquid-liquid extraction into chloroform. Light absorption at 780 nm is measured with a thermal lens spectrophotometer equipped with a semiconductor laser as a light source. The enhancement factor achieved experimentally is 47. The detection limit of Fe(II) ion is 8.1 × 10?9 M, which is 3–4 times better than that obtained by conventional absorption spectrometry, and is governed by the background signal originating from Fe(II) impurity in the reagent. 相似文献
109.
Takanobu Saitou Yushu Jin Kotaro Isobe Takuya Suga Jun Takaya Nobuharu Iwasawa 《化学:亚洲杂志》2020,15(13):1941-1944
The Rh‐catalyzed direct carboxylation of alkenyl C?H bonds was achieved by using pyrazole as a removable directing group. In the presence of 5 mol% RhCl3 ? 3H2O, 6 mol% P(Mes)3, and 2 equiv. of AlMe2(OMe), the alkenyl C?H bond of various alkenylpyrazoles was directly carboxylated in good yields under CO2 atmosphere. Furthermore, several useful transformations of the pyrazole moiety of the product were achieved to afford synthetically useful carboxylic acid derivatives in good yields. 相似文献
110.
Hiroki Fukunaga Dr. Wataru Kosaka Honoka Nemoto Dr. Kouji Taniguchi Dr. Shogo Kawaguchi Dr. Kunihisa Sugimoto Prof. Dr. Hitoshi Miyasaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16755-16766
The insertion of “sandwiched spins” between magnetic layers could efficiently affect the interlayer magnetic correlations, but doing so increases the complexity in the interlayer spin alignment because of competition between the inserted spin-layer interaction JNNI and the interlayer through-space interaction JNNNI if the magnitude of JNNI is of the same order as JNNNI with reciprocal signs of the respective interactions. Herein, systematic tuning of the magnetic phase variations by JNNI and JNNNI in two kinds of metal-variable isostructural series of supramolecular pillared layer magnets [MCp*2][{Ru2II,II(2,3,5,6-F4CO2)4}2(TCNQ)] ⋅ 2 DCE (M=Co, Fe, Cr; 2,3,5,6-F4PhCO2−=2,3,5,6-tetrafluorobenzoate; TCNQ=7,7,8,8-tetracyano-p-quinodimethane; DCE=1,2-dichloroethane) and their DCE-free series, in which [MCp*2]+ (Cp*=η5-C5Me5) species with S=0, 1/2, and 3/2 for M=Co, Fe, Cr, respectively, are sandwiched between ferrimagnetic layers of [{Ru2}2(TCNQ)]−, is demonstrated. The results showed that the flexible magnetic natures of these magnets are changeable in dependence on JNNI and JNNNI, as well as on interlayer inserted spins M. 相似文献