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11.
M Kaneko T Kobayashi H Takano T Ohnishi T Kaku T Nishi C Kawase K Kaneko 《Radioisotopes》1989,38(8):344-346
Thyroid scintigraphy in rats and mice with 99mTc and 123I was attempted to examine whether this modality might be used in small animals and to describe the possibilities of its application in examining experimentally produced thyroid diseases. A human gamma camera with a pinhole collimator improved for small animals was used for imaging. Thyroid images with 99mTc were obtained 20 minutes after injection and those with 123I were 24 hours after administration. All the scintigrams, although those obtained from mice with 99mTc displayed overlapped salivary gland images, demonstrated sufficiently clear images in size and shape, which showed that thyroid scintigraphy in small animals should be applicable in examining experimentally produced thyroid diseases. 相似文献
12.
[reaction: see text] The enantioselective total synthesis of (+)-allocyathin B(2) has been achieved. Our approach features a convergent enantioselective construction of the 5-6-7 tricyclic core system using the originally developed chiral building blocks via asymmetric catalysis, the intramolecular aldol reaction in high yield, successful samarium diiodide-mediated ring expansion, and a newly developed double-bond installation method. 相似文献
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Yukihiro Shintani Keiji Hirako Masanori Motokawa Yoshihiko Takano Masahiro Furuno Hiroyoshi Minakuchi Mitsuyoshi Ueda 《Analytical sciences》2004,20(12):1721-1723
An interconnecting technique, the "PDMS connection method", for quartz microchips in a high-pressure system is presented. The connection between quartz microchips is an essential technology for modular microfluidic devices, such as microchip-HPLC. PDMS was applied to the seal material, being spread on the seal side of the chips, and set into the metal housing. The characteristics of the PDMS connection method concerning pressure resistance and the extension of the peak were examined. The experimental results showed a good seal at 5 MPa, which seem to be sufficient for realizing microchip-HPLC utilizing a monolithic silica capillary column as a separation medium. The influence of the extra column effect on chromatographic separation was almost the same as in the case using a commercial union fitting. In addition, the PDMS connection enabled the detachability of chip-based modules with user-friendliness. Our experimental findings suggest that the novel PDMS connection method can possibly be applied as a generic technology in high-pressure microTAS. 相似文献
17.
127I M?ssbauer spectra of good quality were obtained at 20 K using a Zn127mTe source produced by high flux neutron irradiation of 66Zn-126Te at reactor core. The M?ssbauer spectra for KI and some iodine(III) compounds with absorption intensity of about 5% suggest that the 127I M?ssbauer spectroscopy is useful in elucidating the bonding nature of the iodine compounds. Preparative method of the M?ssbauer source and experimental technique are reported in detail. 相似文献
18.
Properties of Sr2Cu(PO4)2 and Ba2Cu(PO4)2 having [Cu(PO4)2]∞ linear chains in their structures with Cu-O-P-O-Cu linkages were studied by magnetic susceptibility (T=2-400 K, H=100 Oe) and specific heat measurements (T=0.45-21 K). Magnetic susceptibility versus temperature curves, χ(T), showed broad maxima at TM=92 K for Sr2Cu(PO4)2 and TM=82 K for Ba2Cu(PO4)2 characteristic of quasi-one-dimensional systems. The χ(T) data were excellently fitted by the spin susceptibility curve for the uniform S=1/2 chain (plus temperature-independent and Curie-Weiss terms) with g=2.153(4) and J/kB=143.6(2) K for Sr2Cu(PO4)2 and g=2.073(4) and J/kB=132.16(9) K for Ba2Cu(PO4)2 (Hamiltonian H=JΣSiSi+1). The similar J/kB values were obtained from the specific heat data. No anomaly was observed on the specific heat from 0.45 to 21 K for both compounds indicating that the temperatures of long-range magnetic ordering, TN, were below 0.45 K. Sr2Cu(PO4)2 and Ba2Cu(PO4)2 are an excellent physical realization of the S=1/2 linear chain Heisenberg antiferromagnet with kBTN/J<0.34% together with Sr2CuO3 (kBTN/J≈0.25%) and γ-LiV2O5 (kBTN/J<0.16%). Sr2Cu(PO4)2 and Ba2Cu(PO4)2 were stable in air up to 1280 and 1150 K, respectively. 相似文献
19.
Syntheses of several 1-spiroisoquinoline derivatives (VIII, IX, X, XI, XII, XIII, and XIV) were carried out and their unique mass spectral fragmentations were reported. The presence of carbonyl groups at the C-9 and C-14 positions caused cleavage of the five membered ring through the elimination of one or two carbon monoxide groups. This led to the formation of the three membered ring system on the fragmentation pathway. 相似文献
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Electrolytic coupling reaction of laudanosine (1) gave the O-methylflavinantine (II). N-Ethoxycarbonylated dihydrostilbene (IVa) gave a rearranged dienone (Va) and N-trifluoro-acetylated dihydrostilbene (IVb) contrastively gave an unrearranged dienone (Vb). 相似文献