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991.
Jingjing Zhu Yue Wang Zhenxiang Li Si’an Fang Junbo Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):211-216
In this study, phenylalanine dithiocarbamate (PHEDTC) ligand was successfully synthesized and then radiolabeled with [99mTcO]3+ core and [99mTc≡N]2+ core to produce 99mTcO–PHEDTC and 99mTcN–PHEDTC, respectively. Both complexes were prepared with high radiochemical purity and had good stability. The partition coefficient results showed they were hydrophilic, while 99mTcN–PHEDTC was more hydrophilic than 99mTcO–PHEDTC. The biodistribution study in mice bearing S 180 tumor showed that 99mTcO–PHEDTC and 99mTcN–PHEDTC had high tumor uptake at 2 h post-injection, 1.91 and 1.21, respectively. The good uptake and retention in tumor together with favorable tumor-to-muscle ratios make them promising candidates for further evaluation as potential tumor imaging agents. 相似文献
992.
In this paper, the tangential and normal discontinuities at the interface between the scatterer and the matrix are independently modeled, and these relative displacements are directly proportional to the corresponding components of tractions at the interface. The generation of full band-gaps is investigated on the basis of the derived imperfect interface conditions for a sonic plate with an array of acoustic piezoceramic hollow spheres scatterers embedded in an epoxy matrix. The scatterers are made from functionally graded materials with radial polarization. Numerical evaluation has shown that imperfect interface may have a significant effect on the increasing of the length of the full band-gaps. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
993.
A. V. Geliev Kh. D. Do B. V. Egorov Yu. E. Markachev K. B. Tereshkina D. M. Shogin V. I. Khromov 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(1):124-130
The correlation dependence of the critical Reynolds number of the laminar-turbulent transition on the equilibrium constant
of dimerization in a gas during gas flow in dry or sprayed tubes is presented. A new approach to this problem is suggested
related to the use of the quasi-chemical cluster gas model developed by the authors. 相似文献
994.
D. Ieşan 《Nonlinear Analysis: Real World Applications》2011,12(1):513-524
In this paper we present a theory of mixtures of elastic solids with initial stresses and initial heat flux. First, we establish the equations governing the small deformations superposed on nonlinear deformations of mixtures. Then, we derive the basic equations of prestressed mixtures with initial heat flux. The continuous dependence of the solutions upon initial data and body supplies is established. The theory is used to study the deformation of a prestressed spherical shell subjected to constant pressures. 相似文献
995.
Miroslav Bartušek Mariella Cecchi Zuzana Došlá Mauro Marini 《Central European Journal of Mathematics》2011,9(1):184-195
Globally positive solutions for the third order differential equation with the damping term and delay,
$
x' + q(t)x'(t) - r(t)f(x(\phi (t))) = 0,
$
x' + q(t)x'(t) - r(t)f(x(\phi (t))) = 0,
相似文献
996.
Siloxane-terminated solubilizing side chains: bringing conjugated polymer backbones closer and boosting hole mobilities in thin-film transistors 总被引:1,自引:0,他引:1
Mei J Kim do H Ayzner AL Toney MF Bao Z 《Journal of the American Chemical Society》2011,133(50):20130-20133
We introduce a novel siloxane-terminated solubilizing group and demonstrate its effectiveness as a side chain in an isoindigo-based conjugated polymer. An average hole mobility of 2.00 cm(2) V(-1) s(-1) (with a maximum mobility of 2.48 cm(2) V(-1) s(-1)), was obtained from solution-processed thin-film transistors, one of the highest mobilities reported to date. In contrast, the reference polymer with a branched alkyl side chain gave an average hole mobility of 0.30 cm(2) V(-1) s(-1) and a maximum mobility of 0.57 cm(2) V(-1) s(-1). This is largely explained by the polymer packing: our new polymer exhibited a π-π stacking distance of 3.58 ?, while the reference polymer showed a distance of 3.76 ?. 相似文献
997.
Ultrahigh mobility in polymer field-effect transistors by design 总被引:1,自引:0,他引:1
Tsao HN Cho DM Park I Hansen MR Mavrinskiy A Yoon do Y Graf R Pisula W Spiess HW Müllen K 《Journal of the American Chemical Society》2011,133(8):2605-2612
In this article, the design paradigm involving molecular weight, alkyl substituents, and donor-acceptor interaction for the poly[2,6-(4,4-bis-alkyl-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (cyclopentadithiophene-benzothiadiazole) donor-acceptor copolymer (CDT-BTZ) toward field-effect transistors (FETs) with ultrahigh mobilities is presented and discussed. It is shown that the molecular weight plays a key role in improving hole mobilities, reaching an exceptionally high value of up to 3.3 cm(2) V(-1) s(-1). Possible explanations for this observation is highlighted in conjunction with thin film morphology and crystallinity. Hereby, it is found that the former does not change, whereas, at the same time, crystallinity improved with ever growing molecular weight. Furthermore, other important structural design factors such as alkyl chain substituents and donor-acceptor interaction between the polymer backbones potentially govern intermolecular stacking distances crucial for charge transport and hence for device performance. In this aspect, for the first time we attempt to shed light onto donor-acceptor interactions between neighboring polymer chains with the help of solid state nuclear magnetic resonance (NMR). On the basis of our results, polymer design principles are inferred that might be of relevance for prospective semiconductors exhibiting hole mobilities even exceeding 3 cm(2) V(-1) s(-1). 相似文献
998.
Sol-gel based alumina powders with catalytic applications 总被引:1,自引:0,他引:1
Maria Cri?an Maria ZaharescuValluri Durga Kumari Machiraju SubrahmanyamDorel Cri?an Nicolae Dr?ganM?lina R?ileanu Mihaela JitianuAdriana Rusu Gullapelli SadanandamJakkidi Krishna Reddy 《Applied Surface Science》2011,258(1):448-455
The sol-gel process provides a new approach to the preparation of oxide materials and offers many advantages for making catalysts. Since homogeneous mixing can be achieved at the molecular scale, the chemical reactivity of the oxide surface can be greatly enhanced; thus powders with high surface area and optimized pore size distribution can be obtained at low temperatures. In the present work NiO/Al2O3 sol-gel catalysts were obtained by simultaneous gelation of aluminium isopropoxide and nickel nitrate. A comparative study with pure sol-gel alumina was also realized. By physical-structural studies the changes induced by the introduction of the Ni precursor, before and after aluminium alkoxide hydrolysis were highlighted. The introduction of Ni at the beginning of the reaction favors γ-Al2O3 crystallization. When Ni is added at the end of reaction, it delays the alumina crystallization and induces the disorder of the lattice. The obtained Ni doped sol-gel derived alumina has been used as catalyst in the finished form for glycerol reforming to generate H2 for fuel cell applications. Some evaluation results of Ni-doped alumina combined with TiO2 in photocatalytic glycerol reforming reaction have been included. 相似文献
999.
Berna Körpınar Fehmi Saltan Armağan Kınal 《International Journal of Polymer Analysis and Characterization》2020,25(3):134-146
AbstractIn this study, it has been demonstrated that poly(styrene-co-1-methylpyrenyl methacrylate) macro-photoinitiator (PSMM) containing side chain pyrene moieties were successfully prepared using “radical polymerization method.” Firstly, 1-pyrene methanol and methacryloyl chloride were reacted in dichloromethane for 24?h at 0?°C in order to give 1-methoxy pyrene methacrylate macromonomer. Then styrene was polymerized with this macromonomer to obtained macro-photoinitiator. The synthesized copolymer is also both computationally and experimentally demonstrated that the macro-photoinitiator obtained has similar absorption characteristics with the parent pyrene molecule. According to obtained results, the synthesized copolymer was more effective in the presence of triethyl amine as a macro-photoinitiator. 相似文献
1000.
Bestenur YALIN Doan AKCAN brahim Erturul YALIN Mehmet Can ALPHAN Kenan ENTÜRK brahim lker
ZYT Lütfi ARDA 《Turkish Journal of Chemistry》2020,44(4):1177
The objective of this study is to synthesize ZnO and Mg doped ZnO (Zn1−xMgxO) nanoparticles via the sol-gel method, and characterize their structures and to investigate their biological properties such as antibacterial activity and hemolytic potential.Nanoparticles (NPs) were synthesized by the sol-gel method using zinc acetate dihydrate (Zn(CH3COO)2.2H2O) and magnesium acetate tetrahydrate (Mg(CH3COO)2.4H2O) as precursors. Methanol and monoethanolamine were used as solvent and sol stabilizer, respectively. Structural and morphological characterizations of Zn1−xMgxO nanoparticles were studied by using XRD and SEM-EDX, respectively. Photocatalytic activities of ZnO and selected Mg-doped ZnO (Zn1−xMgxO) nanoparticles were investigated by degradation of methylene blue (MeB). Results indicated that Mg doping (both 10% and 30%) to the ZnO nanoparticles enhanced the photocatalytic activity and a little amount of Zn0.90 Mg0.10 O photocatalyst (1.0 mg/mL) degraded MeB with 99% efficiency after 24 h of irradiation under ambient visible light. Antibacterial activity of nanoparticles versus Escherichia coli ( E. coli ) was determined by the standard plate count method. Hemolytic activities of the NPs were studied by hemolysis tests using human erythrocytes. XRD data proved that the average particle size of nanoparticles was around 30 nm. Moreover, the XRD results indicatedthat the patterns of Mg doped ZnO nanoparticles related to ZnO hexagonal wurtzite structure had no secondary phase for x ≤ 0.2 concentration. For 0 ≤ x ≤ 0.02, NPs showed a concentration dependent antibacterial activity against E. coli . While Zn0.90Mg0.10 O totally inhibited the growth of E. coli , upper and lower dopant concentrations did not show antibacterial activity. 相似文献
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