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181.
Kyung Sook Kim MD. Shakilur Rahman Manwoo Lee Guinyun Kim Pham Duc Khue Nguyen Van Do Moo-Hyun Cho In Soo Ko Won Namkung H. Naik Tae-Ik Ro 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):869-877
We measured the isomeric yield ratios for the photonuclear reactions of 93Nb(??,4n)89m,gNb and natMo(??,xnp)95m,gNb by using the activation method. The high-purity 93Nb and natMo metallic foils in disc shape were irradiated with uncollimated bremsstrahlung beams of 50-, 60-, and 70-MeV generated from an electron linear accelerator in Pohang Accelerator Laboratory. The induced activities in the irradiated foils were measured by the high-resolution ??-ray spectrometry with a calibrated high-purity Germanium (HPGe) detector coupled to a PC-based 4?K multichannel analyzer. The reaction 93Nb(??,4n)89m,gNb was studied for the first time which has no comparable literature data. The result of 95m,gNb isomeric pair was measured based on (??,p), (??,np), and (??,2np) reactions which is the first measurement at the intermediate energy region of 50?C70-MeV with a natMo target. 相似文献
182.
W. Roβbander 《Isotopes in environmental and health studies》2013,49(12):477-480
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184.
Sydulu Singu Bal Srinivasan Palaniappan Yoon Kuk Ro 《Journal of Solid State Electrochemistry》2016,20(12):3447-3457
Journal of Solid State Electrochemistry - Nanocomposites consisting of the conducting polymer, polyaniline (PANI), and multiwalled carbon nanotubes (MWNT) were prepared by in situ emulsion... 相似文献
185.
Let X be a projective variety of dimension n and L be a nef divisor on X. Denote by the d-dimensional Seshadri constant of r very general points in X. We prove that
相似文献
186.
A comparison between in vitro and in vivo experiments conducted to investigate the acoustic properties of a novel, 1.2 μm diameter poly(lactic-co-glycolic acid) (50:50) (PLGA) ultrasound contrast agent, the development of which was described previously by us, is presented. A pulse-echo setup was used to determine enhancement in vitro. Additional in vitro studies further characterized the hollow microcapsules, including resonance frequency from attenuation measurements (from 2.25 to 15 MHz) and temperature effects (25 °C vs. 37 °C). In vivo, four rabbits received intravenous injections of the agent (dose range: 0.005–0.13 ml/kg). Quantitative in vivo dose–responses were calculated off-line using spectral power analysis of audio Doppler signals acquired from a custom-made 10 MHz cuff transducer placed around the surgically exposed distal aorta. This frequency was chosen since the very shallow scanning depths encountered in rabbits, in particular for the cuff transducer placed directly around the vessel, necessitates the use of high frequency imaging devices with sufficient spatial resolution to enable meaningful measurements. For qualitative assessments, two rabbits were imaged pre- and post-contrast administration (dose: 0.1 ml/kg) in power Doppler mode. Significant acoustic enhancements (up to 24 dB) were reported both in vitro and in vivo. Moreover, the rabbits did not show any adverse side effects from multiple injections (>20) of the agent. Measured in vitro resonance frequency between 3.09 and 3.49 MHz was lower than predicted for a similar sized free bubble, potentially due to capsule wall structure. Minimal loss of signal (4 dB) was observed at 25 °C over 20 min of insonation at 5 MHz but at 37 °C the signal dropped close to base line within the first 5 min. This temperature sensitivity could be due to loss of capsule integrity (and hence loss of gas). Potential causes include increased hydrolysis or polymer softening and increased water uptake by the shell at temperatures closer to the glass transition temperature (Tg). 相似文献
187.
Dong Hyun Kim Chung Sub Kim Lalita Subedi Sun Yeou Kim Kang Ro Lee 《Tetrahedron letters》2019,60(41):151130
Phytochemical investigation of EtOH extract of NIRAM, natural dye from Polygonum tinctorium, resulted in the purification of nine alkaloid compounds (1–9) including four new compounds (1–4). Structures of these new compounds were elucidated by 1D and 2D NMR (1H and 13C NMR, 1H–1H COSY, 1H–13C HSQC, 1H–13C HMBC), IR, UV, HR-ESI-MS, and ECD spectra. Isolated compounds (1–9) were tested for their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells. Compounds 1–3, 5, and 7 showed potent NO production inhibitory activities, with IC50 values of 3.88–22.87 μM. 相似文献
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190.
E. Ziegler U. Roßmann F. Litvan H. Meier 《Monatshefte für Chemie / Chemical Monthly》1962,93(1):26-33
Zusammenfassung Es werden Synthesen basischer Äther von cyclischen Malonylverbindungen des Phenothiazins, Carbazols, Dihydroacridins und Iminodibenzyls beschrieben.Herrn Prof. Dr.A. Zinke in Freundschaft und Verehrung zum 70. Geburtstag gewidmet. 相似文献