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1.
Photoresponsive biomaterials are experiencing a transition from in vitro models to in vivo demonstrations that point toward clinical translation. Dynamic hydrogels for cell encapsulation, light-responsive carriers for controlled drug delivery, and nanomaterials containing photosensitizers for photodynamic therapy are relevant examples. Nonetheless, the step to the clinic largely depends on their combination with technologies to bring light into the body. This review highlights the challenge of photoactivation in vivo, and presents strategies for light management that can be adopted for this purpose. The authors’ focus is on technologies that are materials-driven, particularly upconversion nanoparticles that assist in “direct path” light delivery through tissue, and optical waveguides that “clear the path” between external light source and in vivo target. The authors’ intention is to assist the photoresponsive biomaterials community transition toward medical technologies by presenting light delivery concepts that can be integrated with the photoresponsive targets. The authors also aim to stimulate further innovation in materials-based light delivery platforms by highlighting needs and opportunities for in vivo photoactivation of biomaterials. 相似文献
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A. Hernández O. Arés C. Hart D. Domínguez H. Pastoriza A. Butera 《Journal of Low Temperature Physics》2004,135(1-2):119-122
The response of mesoscopic superconductors to an ac magnetic field is investigated both experimentally and with numerical simulations. We study small square samples with dimensions of the order of the penetration depth. We obtain the ac susceptibitity χ=χ′+iχ″ at microwave frequencies as a function of the dc magnetic field H dc. We find that the dissipation, given by x″, has a non monotonous behavior in mesoscopic samples. In the numerical simulations we obtain that the dissipation increases before the penetration of vortices and then it decreases abruptly after vortices have entered, the sample. This is verified experimentally, where we find that χ″ has strong oscillations as a function of H dc in small squares of Pb. 相似文献
4.
Ayhan Demirbas M. Masuk Kü ü k Yunus Erdogan M. Ya in Nutku Oktay Torul 《Petroleum Science and Technology》1992,10(2):185-197
A kinetic study of pyrolysis of dried black liquor was performed using a Netzsch 429 Thermogravimetric Analyzer. It was found that as conversion increases from 10 to 45% the apparent pyrolysis activation energy for black liquor increases from 77.20 to 112.74 KJ/mol. For black liquor the order of reaction was found to be first-order. The reaction rate constant was found to be 2.12×109 min. These results are in agreement with the data reported by other investigators on biomass pyrolysis. 相似文献
5.
Pori Maja Arčon Iztok Dasireddy Venkata D. B. C. Likozar Blaž Orel Zorica Crnjak Marinšek Marjan 《Catalysis Letters》2021,151(11):3114-3134
Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature... 相似文献
6.
Sibel Irmak Halil Ibrahim Yavuz Oktay Erbatur 《Applied catalysis. B, Environmental》2006,63(3-4):243-248
Degradation of 4-chloro-2-methylphenol (PCOC), a refractory toxic chemical emitted to the environment from the industrial production of phenoxy herbicides was studied in aqueous solution. Electro-Fenton and photoelectro-Fenton processes were used as the degradation methods. H2O2, produced by the reduction of oxygen at carbon cathode reacted with dissolved metal ions to form hydroxyl radicals, which in turn reacted with PCOC sequentially to degrade the aromatic ring. The effects of using different [Fe2+]/[PCOC]0 and the effect of replacing Fe2+ by Mn2+ ion have been examined. It was found that degradation rate was increased with increasing [Fe2+]/[PCOC]0 ratio from 2 to 4. However, the total charge utilized during the treatment was also increased. The efficiency of PCOC degradation was observed to be higher when Mn2+ was used as the catalyst. The mineralization of aqueous solutions of PCOC, withdrawn from the reactor at certain time interval, has been followed by total organic carbon (TOC) decay and dechlorination. A fast and complete degradation of the aromatic ring was achieved in photoelectro-Fenton system. 41.7% TOC decay and complete dechlorination were observed by consuming only 141.4 C electrical charge during a 300 min photoelectron-Fenton treatment. In the case of electro-Fenton system, 280.7 C electrical charge was consumed during 450 min of electrolysis to attain a similar degradation of PCOC. 14.9% TOC removal and 89.3% dechlorination have been obtained in this system under the applied conditions. 相似文献
7.
Juan Chirinos Jose Arévalo Tamara Rajmankina Angel Morillo Darmenia Ibarra Ali Bahsas Alvaro Parada 《Polymer Bulletin》2004,51(5-6):381-387
Summary The complex
5-(C5H5)2Ti
(1-OC(O)C6H5)2
was synthesized and activated with MA0 for ethylene
polymerization. The resultant polymer is UHMW-PE with a
viscosimetric molecular weight of Mv = 6.8 x
106 to 0.7 x
106 g/mol dependent on the
temperature of the reaction. The effects of the Al/Ti molar
ratio and temperature of the reaction on the catalytic activity
and polymer properties were studied. 相似文献
8.
9.
J. F. Muñoz‐Rosas E. Álvarez‐Verdejo M. N. Pérez‐Aróstegui L. Gutiérrez‐Gutiérrez 《Quality and Reliability Engineering International》2016,32(2):453-464
A control chart is a very common tool used to monitor the quality of business processes. An estimator of the process variability is generally considered to obtain the control limits of a chart when parameters of the process are unknown. Assuming Monte Carlo simulations, this paper first compares the efficiency of the various estimators of the process variability. Two empirical measures used to analyze the performance of control charts are defined. Results derived from various empirical studies reveal the existence of a linear relationship between the performance of the various estimators of the process variability and the performance of charts. The various Monte Carlo simulations are conducted under the assumption that the process is in both situations of in‐control and out‐of‐control. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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