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排序方式: 共有1923条查询结果,搜索用时 16 毫秒
151.
Dr. Luca Gobbi Dr. Joël Mercier Dr. Benny Bang-Andersen Dr. Jean-Marie Nicolas Dr. John Reilly Björn Wagner Dr. David Whitehead Dr. Emmanuelle Briard Dr. R. Paul Maguire Dr. Edilio Borroni Dr. Yves P. Auberson 《ChemMedChem》2020,15(7):560-560
Nonspecific binding (NSB) is a key parameter in optimizing PET imaging tracers. We compared the ability to predict NSB of three available methods: LIMBA, rat fu,brain, and CHI(IAM). Even though NSB is often associated with lipophilicity, we observed that logD does not correlate with any of these assays, clearly indicating that lipophilicity, while influencing NSB, is insufficient to predict it. A cross-comparison of the methods showed that all three correlate and are useful predictors of NSB. The three assays, however, rank the molecules slightly differently, illustrating the challenge of comparing molecules within a narrow chemical space. We also noted that CHI(IAM) values more effectively predict VNS, a measure of in vivo NSB in the human brain. CHI(IAM) measurements might be a closer model of the actual physicochemical interaction between PET tracer candidates and cell membranes, and seems to be the method of choice for the optimization of in vivo NSB. 相似文献
152.
Patrick Illert Björn Wängler Carmen Wängler Frank Zöllner Tanja Uhrig Shanna Litau Marc Pretze Thorsten Röder 《应用聚合物科学杂志》2019,136(19):47571
A dual contrast agent for computed tomography (CT) and magnetic resonance imaging (MRI) was synthesized via microemulsion polymerization. This contrast agent consists of Fe3O4 particles (d = 7 nm) with an iodine-carrying nanopolymeric shell, with overall particle sizes ranging from 50 to 250 nm. 2-Methacryloyloxyethyl(2,3,5-triiodobenzoate) was used as the monomer. Sodium oleate was used as the surfactant and its amount was varied to control the overall particle size. The composite nanoparticles were mainly characterized via dynamic light scattering, with further analyses using transmission electron microscopy and atomic force microscopy. The particles provided a highly visible contrast in CT and MR images. A template for biomedical applications was created by adding a comonomer and the particles were further functionalized with the somatostatin analogue Tyr3-octreotate. The particles were tested for specific uptake into somatostatin receptor-positive AR42J cells. The additional uptake of the functionalized particles was investigated. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47571. 相似文献
153.
154.
Helga Gunnlaugsdottir Björn Sivik 《Journal of the American Oil Chemists' Society》1997,74(11):1483-1490
A combined process of lipase (E.C. 3.1.1.3) catalysis and extraction of product with supercritical carbon dioxide was studied.
The effect of different flow rates of the extraction fluid on the selective removal of the ethyl esters (EE) synthesized in
a lipase-catalyzed alcoholysis of cod liver oil with ethanol was investigated. The faster the flow rate, the faster the extraction
rate and the higher the recovery of EE. For example, after a 270-min extraction, the total recovery of EE was 1520 mg for
a flow rate of 0.3 liter carbon dioxide at atmospheric pressure and room temperature/min (NL/min) as compared to 250 mg when
0.015 NL/min was used. The concentration of EE in the carbon dioxide was found to decrease with increasing flow rate, which
indicates that the rate of diffusion of EE limits their extraction at fast flow rates. A high flow rate was found to result
in a more selective extraction of EE, i.e., less amounts of other lipid components present in the reaction mixture were coextracted
with the EE. Further, by increasing the flow rate, the equilibrium of the reaction was shifted slightly toward ester synthesis.
An increase in the flow rate from 0.015 to 0.075 NL/min resulted in an approximately 10% increase in total conversion (from
73 to 82%), whereas only a negligible increase was obtained when the flow rate was increased further to 0.15 NL/min. 相似文献
155.
Arvani Maedeh Keskinen Jari Railanmaa Anna Siljander Sanna Björkqvist Tomas Tuukkanen Sampo Lupo Donald 《Journal of Applied Electrochemistry》2020,50(6):689-697
Journal of Applied Electrochemistry - In this paper, additive layer-by-layer fabrication of a fully screen printed monolithic supercapacitor exhibiting performance comparable with supercapacitors... 相似文献
156.
Provably good multiprocessor scheduling with resource sharing 总被引:2,自引:1,他引:1
We present a 12(1+3R/(4m)) competitive algorithm for scheduling implicit-deadline sporadic tasks on a platform comprising m processors, where a task may request one of R shared resources. 相似文献
157.
Jacob W. Schmidt Anders Bennitz Bj?rn T?ljsten Henning Pedersen 《Canadian Metallurgical Quarterly》2010,14(4):397-405
A durable and very efficient external strengthening system is achieved if steel tendons for posttensioning applications can be replaced with carbon fiber-reinforced polymer (CFRP) tendons, and if reliable anchorage systems are developed. This paper presents a newly developed and simple-to-use, two-piece wedge anchorage for CFRP tendons with an integrated sleeve and a differential angle between barrel and wedge sections. Three longitudinal slits are cut into the one-piece wedge, with one slit open and the other two stopping 1 mm from the inner wedge hole. The integrated sleeve holds the wedge’s sections together during presetting and loading, resulting in a circumferential confined gripping of the CFRP tendon and optimized surface friction area. Therefore, the one-piece wedge differs from conventional wedge systems, where the wedges act separately with adjacent spaces, wedging the separate tendon sleeve in the longitudinal direction. Evaluation of the failure modes during testing was one of the main keys in achieving an increasingly better performance of the anchorage until the final anchorage was developed. The obtained failure modes are therefore described to enlighten the importance of addressing them when testing. The test setup used and measured behavior are described further together with the loading procedure. The anchorage reached the full capacity of the CFRP tendon and was seen to ensure a stable load of fracture. 相似文献
158.
Abramowitz Jonathan S.; Deacon Brett J.; Olatunji Bunmi O.; Wheaton Michael G.; Berman Noah C.; Losardo Diane; Timpano Kiara R.; McGrath Patrick B.; Riemann Bradley C.; Adams Thomas; Bj?rgvinsson Thr?stur; Storch Eric A.; Hale Lisa R. 《Canadian Metallurgical Quarterly》2010,22(1):180
Although several measures of obsessive-compulsive (OC) symptoms exist, most are limited in that they are not consistent with the most recent empirical findings on the nature and dimensional structure of obsessions and compulsions. In the present research, the authors developed and evaluated a measure called the Dimensional Obsessive-Compulsive Scale (DOCS) to address limitations of existing OC symptom measures. The DOCS is a 20-item measure that assesses the four dimensions of OC symptoms most reliably replicated in previous structural research. Factorial validity of the DOCS was supported by exploratory and confirmatory factor analyses of 3 samples, including individuals with OC disorder, those with other anxiety disorders, and nonclinical individuals. Scores on the DOCS displayed good performance on indices of reliability and validity, as well as sensitivity to treatment and diagnostic sensitivity, and hold promise as a measure of OC symptoms in clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
159.
160.
Timothy Wilson Bjørn Clausen Thomas Proffen Jennifer Elle Don Brown 《Metallurgical and Materials Transactions A》2008,39(8):1942-1946
Bulk metallic glasses (BMGs) are an emerging class of materials whose unique properties make them excellent choices for many
applications. As with crystalline metals, the processing and forming techniques used to produce BMG components necessarily
result in residual stresses. However, traditional diffraction stress analysis is difficult to apply to BMG components, because
they lack the long-range order necessary to produce sharp diffraction patterns, and thus, the internal strains for BMG have
not been examined until recently. In this work, in-situ neutron scattering was used to measure the local elastic internal strain distribution in a Zr57Nb5Cu15.4Ni12.6Al10 BMG as a function of applied stress. Various techniques were used to evaluate the internal strain. The strain was determined
in real space, by measuring changes in the atomic pair distribution function (PDF). These results can be used to help understand
the elastic deformation of BMGs as well be to evaluate current models of BMG deformation.
This article is based on a presentation given in the symposium entitled “Bulk Metallic Glasses IV,” which occurred February
25–March 1, 2007 during the TMS Annual Meeting in Orlando, Florida under the auspices of the TMS/ASM Mechanical Behavior of
Materials Committee. 相似文献