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941.
Optical Doppler Tomography: Imaging in vivo Blood Flow Dynamics Following Pharmacological Intervention and Photodynamic Therapy 总被引:1,自引:0,他引:1
Zhongping Chen Thomas E. Milner Xiaojun Wang Shyam Srinivas J. Stuart Nelson 《Photochemistry and photobiology》1998,67(1):56-60
A noninvasive optical technique has been developed for imaging in vivo blood flow dynamics and vessel structure with high spatial resolution. The technique is based on optical Doppler tomography, which combines Doppler velocimetry with optical coherence tomography to measure blood flow velocity at discrete spatial locations in turbid biological tissue. Applications of this technique for monitoring changes in blood flow dynamics and vessel structure following pharmacological intervention and photodynamic therapy are demonstrated. 相似文献
942.
Reactivity Controlling Factors for an Aromatic Carbon‐Centered σ,σ,σ‐Triradical: The 4,5,8‐Tridehydroisoquinolinium Ion 下载免费PDF全文
Dr. Nelson R. Vinueza Dr. Bartłomiej J. Jankiewicz Vanessa A. Gallardo Gregory Z. LaFavers Dane DeSutter Dr. John J. Nash Prof. Hilkka I. Kenttämaa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):809-815
The chemical properties of the 4,5,8‐tridehydroisoquinolinium ion (doublet ground state) and related mono‐ and biradicals were examined in the gas phase in a dual‐cell Fourier‐transform ion cyclotron resonance (FT‐ICR) mass spectrometer. The triradical abstracted three hydrogen atoms in a consecutive manner from tetrahydrofuran (THF) and cyclohexane molecules; this demonstrates the presence of three reactive radical sites in this molecule. The high (calculated) electron affinity (EA=6.06 eV) at the radical sites makes the triradical more reactive than two related monoradicals, the 5‐ and 8‐dehydroisoquinolinium ions (EA=4.87 and 5.06 eV, respectively), the reactivity of which is controlled predominantly by polar effects. Calculated triradical stabilization energies predict that the most reactive radical site in the triradical is not position C4, as expected based on the high EA of this radical site, but instead position C5. The latter radical site actually destabilizes the 4,8‐biradical moiety, which is singlet coupled. Indeed, experimental reactivity studies show that the radical site at C5 reacts first. This explains why the triradical is not more reactive than the 4‐dehydroisoquinolinium ion because the C5 site is the intrinsically least reactive of the three radical sites due to its low EA. Although both EA and spin–spin coupling play major roles in controlling the overall reactivity of the triradical, spin–spin coupling determines the relative reactivity of the three radical sites. 相似文献
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944.
945.
MZDASoft: a software architecture that enables large‐scale comparison of protein expression levels over multiple samples based on liquid chromatography/tandem mass spectrometry 下载免费PDF全文
946.
Wenwen Zhang Nelson R. Vinueza Preeta Datta Stephen Michielsen 《Journal of polymer science. Part A, Polymer chemistry》2015,53(13):1594-1599
In many applications, a functional additive is blended into a polymer matrix to enhance its properties. However, when the polymer and functional additive are applied to a surface, the functional molecule may be easily lost. In favorable cases, it may be possible to incorporate the additive directly into the polymer as a comonomer. In this study, a functionalized polymer has been obtained through the combination of linking a photodynamic, antimicrobial dye, Rose Bengal, to vinyl benzyl chloride via etherification and then polymerizing this into a water‐soluble polymer using chain growth copolymerization. Characterization of the efficiency of synthesis, solubility of the final product, and singlet oxygen production rate has been performed. Dialysis was used to determine the extent of incorporation of the dye into the polymer. The chemical structure of the intermediate produced through etherification has been verified. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1594–1599 相似文献
947.
948.
Propylene polymerization reactions with supported Ziegler–Natta catalysts: Observing polymer material produced by a single active center 下载免费PDF全文
Yury V. Kissin Vladimir P. Marin Patricia J. Nelson 《Journal of polymer science. Part A, Polymer chemistry》2017,55(23):3832-3841
Medium‐ and high‐resolution SEM analysis of several Ti‐based MgCl2‐supported Ziegler–Natta catalysts and isotactic polypropylene produced with them is carried out. Each catalyst particle, 35–55 μ in size, produces one polymer particle with an average size of 1.5–2 mm, which replicates the shape of the catalyst particle. Polymer particles contain two distinct morphological features. The larger of them are globules with Dav ~400 nm; from 1 to 2 × 1011 globules per particle. Each globule represents the combined polymer output of a single active center. The globules consist of ~2500 microglobules with an average size of ~20 nm. The microglobules contain several folded polymer molecules; they are the smallest thermodynamically stable macromolecular ensembles in propylene polymerization reactions. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3832–3841 相似文献
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950.
Kathrin E. Peyer Soichiro Tottori Famin Qiu Prof. Dr. Li Zhang Prof. Dr. Bradley J. Nelson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(1):28-38
Helical microrobots have the potential to be used in a variety of application areas, such as in medical procedures, cell biology, or lab‐on‐a‐chip. They are powered and steered wirelessly using low‐strength rotating magnetic fields. The helical shape of the device allows propulsion through numerous types of materials and fluids, from tissue to different types of bodily fluids. Helical propulsion is suitable for pipe flow conditions or for 3D swimming in open fluidic environments. 相似文献