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A.?TserepiEmail author E.?Gogolides A.?Bourkoula A.?Kanioura G.?Kokkoris P.?S.?Petrou S.?E.?Kakabakos 《Plasma Chemistry and Plasma Processing》2016,36(1):107-120
Plasma etching has evolved in an important technology for rapid and cost-effective generation of random or quasi-ordered nanostructures in large areas and in a repeatable manner, if properly controlled. It simultaneously affects the chemical composition of etched surfaces. Thus, plasma etching finds numerous applications in the areas of biomaterials and biomicrosystems, since surface chemistry and topography are proven to influence strongly cell–substrate interactions. Herein, we briefly review published studies addressing cell–surface interactions, especially those focusing on optimal surface properties favoring cell adhesion and proliferation. We show that plasma-based micro- and nano-texturing of polymeric surfaces provides a unique, simple and yet versatile tool for tuning the physicochemical properties of polymeric surfaces to those favoring cell cultures. Plasma etching and nanotexturing is proven indispensable also for the patterning on the same substrate of different chemical and/or topographical areas to induce preferential cell adhesion in predefined areas. In this respect, the implementation of surfaces with extreme wettabilities (superhydrophobic/superhydrophilic patterns) is highly valued and when integrated inside microchannels can add new potential to the current archery of microanalytical devices. The paper concludes with the authors’ view to the future outlook of the niche area of plasma nanotextured polymer surfaces. 相似文献
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K.?ChrissafisEmail author M.?Lalia-Kantouri P.?Aslanidis 《Journal of Thermal Analysis and Calorimetry》2011,104(3):1045-1050
Two series of copper (I) halide complexes formulated as [(L)CuX(μ2-L)2CuX(L)] and [(L)2Cu(μ2-L)2Cu(L)2]2+ 2Χ−, respectively (X = Cl, Br and L = 4,6-dimethylpyrimidine-2-thione (dmpymtH)) were prepared. From the thermogravimetric curves
it was found that among the four studied materials, [Cu2(dmpymtH)6]2+2Cl− presents a lower thermal stability. For the determination of the activation energy (E) two different methods have been used comparatively, since every method has its own error. These methods were the isoconversional
methods of Ozawa, Flynn and Wall (OFW), and Friedman. The dependence of the E on the value of the mass conversion α, as calculated with OFW and Friedman’s methods, can be separated in three distinct regions. The decomposition mechanism is
very complex and can be described using at least three different mechanisms with different activation energies. The best fitting
of experimental data with theoretical models gave nth-order for all the three mechanisms (Fn–Fn–Fn). 相似文献
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Recently, Blecher and Kashyap have generalized the notion of W
*-modules over von Neumann algebras to the setting where the operator algebras are σ closed algebras of operators on a Hilbert space. They call these modules weak* rigged modules. We characterize the weak* rigged modules over nest algebras. We prove that Y is a right weak* rigged module over a nest algebra Alg(M){\rm{Alg}(\mathcal M)} if and only if there exists a completely isometric normal representation F{\Phi } of Y and a nest algebra Alg(N){\rm{Alg}(\mathcal N)} such that Alg(N) F(Y)Alg(M) ì F(Y){\rm{Alg}(\mathcal N) \Phi (Y)\rm{Alg}(\mathcal M)\subset \Phi (Y)} while F(Y){\Phi (Y)} is implemented by a continuous nest homomorphism from M{\mathcal M} onto N{\mathcal N} . We describe some properties which are preserved by continuous CSL homomorphisms. 相似文献
76.
Gábor?Márton Dóra?Tombácz Judit?S?Tóth András?Szabó Zsolt?Boldogk?i ádám?Dénes ákos?Hornyák Antal?Nógrádi 《BMC neuroscience》2010,11(1):65
Background
Genetically modified pseudorabies virus (Prv) proved suitable for the delivery of foreign genes to rodent embryonic neurons ex vivo and maintaining foreign gene expression after transplantation into spinal cord in our earlier study. The question arose of whether human embryonic neurons, which are known to be more resistant to Prv, could also be infected with a mutant Prv. Specifically, we investigated whether a mutant Prv with deleted ribonucleotide reductase and early protein 0 genes has the potential to deliver marker genes (gfp and β-gal) into human embryonic spinal cord neurons and whether the infected neurons maintain expression after transplantation into adult mouse cord. 相似文献77.
The flow induced by a sphere rotating inside a non-Newtonian, Bingham fluid has been investigated numerically. The rotating sphere is enclosed in a concentric cubic box with solid boundaries. The Bingham number varied between 0.01 and 100,000 and the Reynolds number varied between 0.01 and 10,000. The torque increases with the Bingham number and reaches an asymptotic state at large Bn. The torque is independent of the Reynolds number at high Bn. The yielded region around the sphere has been determined and an empirical equation is found for its extent. 相似文献
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G. M. Keserü R. Klinga G. Mezey-Vándor M. Nógrádi G. Tóth 《Monatshefte für Chemie / Chemical Monthly》1994,125(4):425-432
Summary During ketalization with ethyleneglycol an arylideneacetone1 dimerized via its ketal2 to give a 4-acetyl-3,5-diarylcyclohexanone ketal5.
Ketal-vermittelte Diels-Alder-Dimerisierung eines Arylidenacetons
Zusammenfassung Bei der Ketalisierung des Arylidenaceton-Derivates1 erfolgt eine Diels-Alder-Dimerisierung des Ethylenketals2 zu einem 4-Acetyl-3,5-diaryl-cyclohexanon5.相似文献
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