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941.
The mechanism of continuous dissolution was studied using transmission electron microscopy, X-ray diffraction and hardness measurements. The metastable phase was identified in the first stage of dissolution nucleating at the - boundaries. Interface dislocations at the - boundaries forming a perpendicular net in the 110 directions were identified as of screw character and of Burgers vector b=1/2a 110. During dissolution a change of shape of precipitates occurs leading to their fragmentation and to a change of the direction of boundaries into 110 directions. 相似文献
942.
Four notions of controllability for general (i.e., possibly nonregular) implicit linear discrete-time systems are considered. Relationships between them are studied. A Hautus-type characterization of all of these notions is also given.This work was performed under the auspices of RP.I.02: Teoria sterowania i optymalizacji ciagych ukadów dynamicznych i procesów dyskretnych. 相似文献
943.
944.
Novel 7‐maleimido‐2(1H)‐quinolones as potential fluorescent sensors for the detection of sulphydryl groups
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Jolanta Kolińska Aleksandra Grzelakowska Jolanta Sokołowska 《Coloration Technology》2018,134(2):148-155
Novel compounds, based on the 2(1H)‐quinolone skeleton, were synthesised and characterised using 1H‐nuclear magnetic resonance (NMR) spectroscopy and chemical ionisation mass spectrometry (CI MS). Their spectroscopic properties, such as absorption and emission spectra and fluorescence quantum yield, were also examined. 7‐maleimido‐4‐methyl‐2(1H)‐quinolone, 7‐maleimido‐3,4‐dimethyl‐2(1H)‐quinolone, 7‐maleimido‐4‐propyl‐2(1H)‐quinolone and 7‐maleimido‐4‐phenyl‐2(1H)‐quinolone were evaluated as potential sensors for the detection of sulphydryl amino acids groups. These new compounds demonstrate a high ‘turn‐on’ fluorescence response and selectivity towards l ‐cysteine in the presence of other amino acids and metal cations. 相似文献
945.
Jakub Bogusławski Yadong Wang Hui Xue Xiaoxia Yang Dong Mao Xuetao Gan Zhaoyu Ren Jianlin Zhao Qing Dai Grzegorz Soboń Jarosław Sotor Zhipei Sun 《Advanced functional materials》2018,28(28)
Actively mode‐locked lasers offer varying degrees of flexibility for a wider range of applications than their passively modulated counterparts, due to their capability for electrically controlled ultrahigh repetition rate operation. Graphene based electrooptic modulators with unique advantages of broad operation bandwidth and ultrafast speed are suitable for light modulation in various optoelectronic applications. Here, an actively mode‐locked laser with a graphene based electrooptic modulator is reported for the first time. The active mode‐locking technique combined together with the intracavity nonlinear pulse shortening effect allows the generation of transform‐limited 1.44 ps pulses with pulse energy of 844 pJ. The electrically controlled repetition rate of generated pulses, a key performance advantage of active mode‐locking, is also demonstrated. These results provide a practical and effective approach for actively mode‐locked lasers with broad operation bandwidth and compact footprint, which contributes a new way for applications of two‐dimensional (2D) layered materials in ultrafast lasers. 相似文献
946.
Electric Field Assisted Microfluidic Platform for Generation of Tailorable Porous Microbeads as Cell Carriers for Tissue Engineering
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947.
Electric Field Assisted Microfluidic Platform for Generation of Tailorable Porous Microbeads as Cell Carriers for Tissue Engineering
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Marco Costantini Jan Guzowski Paweł J. Żuk Pamela Mozetic Simone De Panfilis Jakub Jaroszewicz Marcin Heljak Mara Massimi Maxime Pierron Marcella Trombetta Mariella Dentini Wojciech Święszkowski Alberto Rainer Piotr Garstecki Andrea Barbetta 《Advanced functional materials》2018,28(20)
Injection of cell‐laden scaffolds in the form of mesoscopic particles directly to the site of treatment is one of the most promising approaches to tissue regeneration. Here, a novel and highly efficient method is presented for preparation of porous microbeads of tailorable dimensions (in the range ≈300–1500 mm) and with a uniform and fully interconnected internal porous texture. The method starts with generation of a monodisperse oil‐in‐water emulsion inside a flow‐focusing microfluidic device. This emulsion is later broken‐up, with the use of electric field, into mesoscopic double droplets, that in turn serve as a template for the porous microbeads. By tuning the amplitude and frequency of the electric pulses, the template droplets and the resulting porous bead scaffolds are precisely produced. Furthermore, a model of pulsed electrodripping is proposed that predicts the size of the template droplets as a function of the applied voltage. To prove the potential of the porous microbeads as cell carries, they are tested with human mesenchymal stem cells and hepatic cells, with their viability and degree of microbead colonization being monitored. Finally, the presented porous microbeads are benchmarked against conventional microparticles with nonhomogenous internal texture, revealing their superior performance. 相似文献
948.
New calcium‐free Na2O–Al2O3–P2O5 bioactive glasses with potential applications in bone tissue engineering
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Oliwia Jeznach Marcin Gajc Karolina Korzeb Andrzej Kłos Krzysztof Orliński Ryszard Stępień Małgorzata Krok‐Borkowicz Łucja Rumian Krzysztof Pietryga Katarzyna Reczyńska Elżbieta Pamuła Dorota A. Pawlak 《Journal of the American Ceramic Society》2018,101(2):602-611
Sodium aluminophosphate glasses were evaluated for their bone repair ability. The glasses belonging to the system 45Na2O–xAl2O3‐(55‐x)P2O5, with x = (3, 5, 7, 10 mol%) were prepared by a melt‐quenching method. We assessed the effect of Al2O3 content on the properties of Na2O–Al2O3–P2O5 (NAP) glasses, which were characterized by density measurements, DSC analyses, solubility, bioactivity in simulated body fluid and cytocompatibility with MG‐63 cells. To the best of our knowledge, this is the first investigation of calcium‐free Na2O–Al2O3–P2O5 system glasses as bioactive materials for bone tissue engineering. 相似文献
949.
Cyclopropaneoctanoic Acid 2‐Hexyl Upregulates the Expression of Genes Responsible for Lipid Synthesis and Release in Human Hepatic HepG2 Cells
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Recently we have found cyclopropaneoctanoic acid 2‐hexyl (CPOA2H) in humans and demonstrated its elevated levels in patients with metabolic diseases associated with hypertriglyceridemia. However, it is still unclear whether CPOA2H may influence lipid metabolism in lipogenic tissues. To verify this, HepG2 hepatocytes and 3T3‐L1 adipocytes were cultured with various concentrations of CPOA2H, and then the expressions of genes associated with lipid metabolism were determined. Incubation with CPOA2H at concentrations found in patients with metabolic diseases enhanced the expression of hepatocyte genes associated with lipid synthesis and release, in particular, the fatty acid synthase gene (nearly 20‐fold increase in the mRNA level). In contrast, incubation with CPOA2H caused the downregulation of most adipocyte genes associated with lipid synthesis, whereas the level of leptin mRNA was increased. These findings suggest that CPOA2H may contribute to hypertriglyceridemia in patients with metabolic diseases, upregulating the expression of hepatocyte genes responsible for lipid synthesis and release. 相似文献
950.
Pawel Stoch Małgorzata Ciecińska Agata Stoch Łukasz Kuterasiński Ireneusz Krakowiak 《Ceramics International》2018,44(1):728-734
In the paper process of sintering of hospital incineration ash as a counterpart of low-level active waste with borosilicate glass frit is presented. It is shown that low porosity glass-ceramic waste-form can be obtained at a temperature range of 850–900 °C. In the sinter, the main crystal phases are wollastonite and aegirine-augite pyroxenes which have a large isomorphous capacity of binding hazardous elements. The crystal phases are fully encapsulated by the glass that provides additional protection against environmental influence. Thus, multibarrier material can be obtained at a temperature considerably lower than vitrification. This, in turn, can improve the economics of immobilization process. 相似文献