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排序方式: 共有268条查询结果,搜索用时 15 毫秒
1.
Karakuş Erman Erdemir Eda Suna Garen Liv Lokman Gunduz Simay Can Şevval Arzu 《Journal of fluorescence》2021,31(6):1617-1625
Journal of Fluorescence - We have constructed a novel fluorescein-based fluorescent chemosensor, FL-In, functionalised with an indole moiety and capable of sensing by both the optical... 相似文献
2.
Igor Rodin Timur Baygildiev Andrey Stavrianidi Arcady Braun Igor Rybalchenko Oleg Shpigun 《Chromatographia》2015,78(7-8):585-591
3.
A feasibility study of X‐ray phase‐contrast mammographic tomography at the Imaging and Medical beamline of the Australian Synchrotron 下载免费PDF全文
Yakov I. Nesterets Timur E. Gureyev Sheridan C. Mayo Andrew W. Stevenson Darren Thompson Jeremy M. C. Brown Marcus J. Kitchen Konstantin M. Pavlov Darren Lockie Francesco Brun Giuliana Tromba 《Journal of synchrotron radiation》2015,22(6):1509-1523
Results are presented of a recent experiment at the Imaging and Medical beamline of the Australian Synchrotron intended to contribute to the implementation of low‐dose high‐sensitivity three‐dimensional mammographic phase‐contrast imaging, initially at synchrotrons and subsequently in hospitals and medical imaging clinics. The effect of such imaging parameters as X‐ray energy, source size, detector resolution, sample‐to‐detector distance, scanning and data processing strategies in the case of propagation‐based phase‐contrast computed tomography (CT) have been tested, quantified, evaluated and optimized using a plastic phantom simulating relevant breast‐tissue characteristics. Analysis of the data collected using a Hamamatsu CMOS Flat Panel Sensor, with a pixel size of 100 µm, revealed the presence of propagation‐based phase contrast and demonstrated significant improvement of the quality of phase‐contrast CT imaging compared with conventional (absorption‐based) CT, at medically acceptable radiation doses. 相似文献
4.
5.
A novel reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides was performed in the presence of silver nitrate or triflate.Conjugated vinyl sulfones as dramatic products were obtained in moderate yields and with Z-selectivity.A free radical mechanism has been proposed to account for the formation of the products. 相似文献
6.
E. Suna 《Chemistry of Heterocyclic Compounds》2012,48(1):44-48
Transition-metal-catalyzed regioselective oxidation of heteroaromatic C–H bonds is highlighted with emphasis on mechanistic issues. 相似文献
7.
Kuo Hsiung Lee 《中国化学快报》2012,23(5):583-586
Two novel styryllactones,goniodilactone(1) and gonioheptenolactone(2),were isolated from the leaves of Goniothalamus cheliensis Hu.Their structures were determined on the basis of spectroscopic data as well as X-ray crystallography analysis. Compounds 1 and 2 exhibited significant cytotoxicities in a panel of human cancer cells,including DU-145,PC-3,MCF-7,A-549, KB and KBvin,with GI50S in the range of 1.29-4.56μg/mL. 相似文献
8.
Imre Miklós Szilágyi Eero Santala Mikko Heikkilä Marianna Kemell Timur Nikitin Leonid Khriachtchev Markku Räsänen Mikko Ritala Markku Leskelä 《Journal of Thermal Analysis and Calorimetry》2011,105(1):73-81
This article demonstrates how important it is to find the optimal heating conditions when electrospun organic/inorganic composite
fibers are annealed to get ceramic nanofibers in appropriate quality (crystal structure, composition, and morphology) and
to avoid their disintegration. Polyvinylpyrrolidone [PVP, (C6H9NO)
n
] and ammonium metatungstate [AMT, (NH4)6[H2W12O40]·nH2O] nanofibers were prepared by electrospinning aqueous solutions of PVP and AMT. The as-spun fibers and their annealing were
characterized by TG/DTA-MS, XRD, SEM, Raman, and FTIR measurements. The 400–600 nm thick and tens of micrometer long PVP/AMT
fibers decomposed thermally in air in four steps, and pure monoclinic WO3 nanofibers formed between 500 and 600 °C. When a too high heating rate and heating temperature (10 °C min−1, 600 °C) were used, the WO3 nanofibers completely disintegrated. At lower heating rate but too high temperature (1 °C min−1, 600 °C), the fibers broke into rods. If the heating rate was adequate, but the annealing temperature was too low (1 °C min−1, 500 °C), the nanofiber morphology was excellent, but the sample was less crystalline. When the optimal heating rate and
temperature (1 °C min−1, 550 °C) were applied, WO3 nanofibers with excellent morphology (250 nm thick and tens of micrometer long nanofibers, which consisted of 20–80 nm particles)
and crystallinity (monoclinic WO3) were obtained. The FTIR and Raman measurements confirmed that with these heating parameters the organic matter was effectively
removed from the nanofibers and monoclinic WO3 was present in a highly crystalline and ordered form. 相似文献
9.
Zhong Lv Zhang Zhi Jie Sun Fei Xue Xian Jin Luo Nai Yun Xiu Li Teng Zong Gen Peng 《中国化学快报》2009,20(8):921-923
A series of novel benzimidazole derivatives was synthesized and their anti-Coxsackie virus B_3(CVB_3) activity was evaluated in VERO cells.Compounds 9 and 10 exhibited better inhibitory activity than those of ribavirin(RBV) with IC_(50) values of 5.30 and 1.06μg/mL,respectively. 相似文献
10.