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11.
12.
Vera A. Schulte Dora F. Alves Paul P. Dalton Martin Moeller Marga C. Lensen Petra Mela 《Macromolecular bioscience》2013,13(5):562-572
Designing three‐dimensional (3D) scaffolds for selective manipulation of cell growth is of high relevance for applications in regenerative medicine. Especially, scaffolds with oriented morphologies bear high potential to guide the restoration of specific tissues. The fabrication of hydrogel scaffolds that support long‐term survival, proliferation, and unidirectional growth of embedded cells is presented here. Parallel channel structures are introduced into the bulk hydrogels by uniaxial freezing, providing stable, and uniform porosity suitable for cell invasion (pore diameters of 5–15 µm). In vitro assessment of the scaffolds with murine fibroblasts (NIH L929) shows a remarkable unidirectional movement along the channels, with the cells traveling several millimeters through the hydrogel.
13.
Dr. Antoine Leliège M. Sc. Jérémie Grolleau M. Sc. Magali Allain Dr. Philippe Blanchard Dr. Dora Demeter Dr. Théodulf Rousseau Dr. Jean Roncali 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(30):9948-9960
Donor–acceptor (D–π–A) systems that combine triarylamine donor blocks and dicyanovinyl (DCV) acceptor groups have been synthesized. Starting from the triphenylamine (TPA)? thiophene? DCV compound ( 1 ) as a reference system, various synthetic approaches have been developed for controlling the light‐harvesting properties and energy levels of the frontier orbitals in this molecule. Thus, the introduction of methoxy groups onto TPA, the replacement of one phenyl ring of TPA by a thiophene ring, or the extension of the π‐conjugating spacer group lead to the modulation of the HOMO level. On the other hand, the fusion of the DCV group onto the vicinal thiophene ring by an ortho‐phenylene bridge allows for a specific fine‐tuning of the LUMO level. The electronic properties of the molecules were analyzed by using UV/Vis spectroscopy and cyclic voltammetry and the compounds were evaluated as donor materials in basic bilayer planar heterojunction solar cells by using C60 as acceptor material. The relationships between the electronic properties of the donors and the performance of the corresponding photovoltaic devices are discussed. Bilayer planar heterojunction solar cells that used reference compound 1 and C70 afforded power‐conversion efficiencies of up to 3.7 %. 相似文献
14.
GVSRPavan Kumar KSrinivasa Rao Arunendra Yadav MLakshman Kumar HSainadh Dora 《印度化学会志》2022,99(5):100338
Groundwater quality is the major concern all over the world. Natural processes and manmade activities are the prime reasons for the contamination of available water resources. It is crucial to assess the quality of groundwater in areas surrounded by various industries. The present study was carried out to assess the groundwater quality during pre-monsoon and post monsoon seasons of 2016, in two mandals of Vizianagaram district of Andhra Pradesh via multivariate statistical analysis and water quality index method. The present work gains importance in light of the construction of proposed international airport at Bhohapuram and the existence of various industries in Pusapatirega mandal. A total of thirty-seven villages, eighteen from Bhogapuram mandal and seventeen from Pusapatirega mandal were selected for the present study. Factor analysis, linear regression analysis, correlation matrix analysis and cluster analysis tools were used to emphasize the parameters influencing quality of water in the chosen study area. From the analysis reports, it was found that the groundwater of the two mandals under investigation was strongly influenced by EC, TDS, total hardness(TH), Ca+2, Mg+2 and K+. During the two seasons under study, the water quality index value was found to be greater than 100 indicating that the water is unfit for human consumption. Concentration of Ca+2, Mg+2 and K+ were found to be beyond the permissible limits prescribed by BIS (2012). Dissolution of calcium and magnesium bearing minerals, mixing of industrial and household wastes may be the reasons for elevated concentration levels of these parameters. 相似文献
15.
Janovszky Dora Sveda Maria Sycheva Anna Kristaly Ferenc Zámborszky Ferenc Koziel Tomasz Bala Piotr Czel Gyorgy Kaptay George 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7141-7157
Journal of Thermal Analysis and Calorimetry - A remarkable number of scientific papers are available in the literature about the bulk amorphous alloys and metallic glasses. Today, DSC is an... 相似文献
16.
Takacs Kata Tatraaljai Dora Pregi Emese Huszthy Peter Pukanszky Bela 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12513-12522
Journal of Thermal Analysis and Calorimetry - A new phosphine-type potential secondary stabilizer was synthesized successfully with large natural raw material content. The stabilizer is a waxy... 相似文献
17.
Tiziana Forleo Alessandro Zappi Dora Melucci Martina Ciriaci Francesco Griffoni Simone Bacchiocchi Melania Siracusa Tamara Tavoloni Arianna Piersanti 《Molecules (Basel, Switzerland)》2021,26(9)
The international seafood trade is based on food safety, quality, sustainability, and traceability. Mussels are bio-accumulative sessile organisms that need regular control to guarantee their safe consumption. However, no well-established and validated methods exist to trace mussel origin, even if several attempts have been made over the years. Recently, an inorganic multi-elemental fingerprint coupled to multivariate statistics has increasingly been applied in food quality control. The mussel shell can be an excellent reservoir of foreign inorganic chemical species, allowing recording long-term environmental changes. The present work investigates the multi-elemental composition of mussel shells, including Al, Cu, Cr, Zn, Mn, Cd, Co, U, Ba, Ni, Pb, Mg, Sr, and Ca, determined by inductively-coupled plasma mass-spectrometry in Mytilus galloprovincialis collected along the Central Adriatic Coast (Marche Region, Italy) at 25 different sampling sites (18 farms and 7 natural banks) located in seven areas. The experimental data, coupled with chemometric approaches (principal components analysis and linear discriminant analysis), were used to create a statistical model able to discriminate samples as a function of their production site. The LDA model is suitable for achieving a correct assignment of >90% of individuals sampled to their respective harvesting locations and for being applied to counteract fraud. 相似文献
18.
José C. González-Iñiguez Víctor M. Ovando-Medina Carlos F. Jasso-Gastinel Dora A. González Jorge E. Puig Eduardo Mendizábal 《Colloid and polymer science》2014,292(6):1269-1275
Nanoparticles of semiconducting polypyrrole (PPy) were synthesized by batch heterophase (BHP) and semicontinuous heterophase polymerization (SHP) using ferric chloride (FeCl3), potassium persulfate (KPS), or ammonium persulfate (APS) as the oxidizing agent, sodium dodecyl sulfate (SDS) as surfactant, and ethanol (EtOH) or iso-pentyl alcohol (iC5OH) as co-surfactants. In all cases, the molar ratios of monomer/oxidizing agent were 1/1. Pyrrol polymerization by BHP and SHP allowed using much lower percentages of surfactant than those employed in microemulsion polymerization of this monomer. The effects of temperature, oxidizing agent, and co-surfactant on conductivity were studied. The polymers were analyzed by transmission electron microscopy (TEM), UV/Visible and Fourier transform infrared (FTIR) spectroscopies, and cyclic voltammetry. Higher PPy conductivities were obtained by polymerizing at 0 °C with FeCl3 as the oxidizing agent, in the presence of iC5OH as co-surfactant. When the reaction was carried out by SHP with low reaction times, smaller particles with similar conductivities were obtained compared to those obtained by BHP; the conductivity of PPy decreases with increasing polymerization time, which can be explained by PPy overoxidation. 相似文献
19.
Celina Love Jan Steinkühler David T. Gonzales Naresh Yandrapalli Tom Robinson Rumiana Dimova Dr. T.-Y. Dora Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6006-6013
In situ, reversible coacervate formation within lipid vesicles represents a key step in the development of responsive synthetic cellular models. Herein, we exploit the pH responsiveness of a polycation above and below its pKa, to drive liquid–liquid phase separation, to form single coacervate droplets within lipid vesicles. The process is completely reversible as coacervate droplets can be disassembled by increasing the pH above the pKa. We further show that pH-triggered coacervation in the presence of low concentrations of enzymes activates dormant enzyme reactions by increasing the local concentration within the coacervate droplets and changing the local environment around the enzyme. In conclusion, this work establishes a tunable, pH responsive, enzymatically active multi-compartment synthetic cell. The system is readily transferred into microfluidics, making it a robust model for addressing general questions in biology, such as the role of phase separation and its effect on enzymatic reactions using a bottom-up synthetic biology approach. 相似文献
20.
Dora Izzo 《Liquid crystals》2020,47(1):99-105
ABSTRACTWe use the Landau theory of phase transitions to describe the phase diagram of a liquid crystal displaying the isotropic (i), nematic (N), smectic-A and smectic-C phases. The order parameter of the smectic-C phase is defined as the projection of the director on the plane of the smectic layers, vanishing in the smectic-A phase. We present a detailed phase diagram that shows transition between any two of these phases, containing a triple point INA, a Lifshitz point NAC, a tricritical at the NA line, and a critical end point IAC. As one approaches the NC line from the smectic-C phase, the tilt angle approaches a nonzero value, but if the AC line is approached, the tilt angle vanishes according to the distance to the AC line to the power 1/2. 相似文献