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91.
Dispinar T Van Camp W De Cock LJ De Geest BG Du Prez FE 《Macromolecular bioscience》2012,12(3):383-394
A Michael addition strategy involving the reaction between a maleimide double bond and amine groups is investigated for the synthesis of cryogels at subzero temperature. Low-molecular-weight PEG-based building blocks with amine end groups and disulfide-containing building blocks with maleimide end groups are combined to synthesize redox-responsive PEG cryogels. The cryogels exhibit an interconnected macroporous morphology, a high compressive modulus and gelation yields of around 95%. While the cryogels are stable under physiological conditions, complete dissolution of the cryogels into water-soluble products is obtained in the presence of a reducing agent (glutathione) in the medium. Cell seeding experiments and toxicologic analysis demonstrate their potential as scaffolds in tissue engineering. 相似文献
92.
B. Saka 《Physics of Wave Phenomena》2012,20(2):107-117
The nonlinear Schr?dinger equation is numerically solved using the collocation method based on quintic B-spline interpolation functions. The efficiency and robustness of the proposed method are demonstrated by standard test problems, such as a one-soliton solution, interaction of two solitons, and formation of a soliton. This method is compared with both the analytical and numerical techniques in the computational section. 相似文献
93.
Atoms constructing an interconnecting metal linein a semiconductor device are transported by electron flowin high density.This phenomenon is called electromigration,which may cause the line failure.In order to characterize theelectromigration failure,a comparison study is carried outwith some typical phenomena treated by fracture mechanicsfor thin and large structures.An example of thin structures,which have been treated by fracture mechanics,is silica optical fibers for communication systems.The damage growth ina metal line by electromigration is characterized in comparison with the crack growth in a silica optical fiber subjectedto static fatigue.Also a brief comparison is made betweenthe electromigration failure and some fracture phenomena inlarge structures. 相似文献
94.
S.?RiEmail author T.?Muramatsu M.?Saka K.?Nanbara D.?Kobayashi 《Experimental Mechanics》2012,52(4):331-340
Measuring accurate displacement distributions for large-scale structures is an important issue and a very challenging task.
Recently, a simple and accurate phase measurement technique called sampling moiré method [Exp Mech 50–4:501–508, (2010)] has been developed for small-displacement distribution measurements. In this method, the phase distribution of moiré fringes
can be analyzed from a single grating image by simultaneously performing down-sampling image processing and intensity-interpolation
to generate multiple phase-shifted moiré fringe images. In addition, the phase of the original grating can also be obtained
from the phase of the moiré fringe by adding the phase of the sampling grating. In this study, the measurement accuracy of
the sampling moiré method was analyzed through computer simulations and a displacement measurement experiment. Four factors
of the sampling moiré method were investigated, including the sampling pitch, the order of the intensity-interpolation, random
noise, and the form of grating. The results show that determining the optimal sampling pitch is an important factor for obtaining
better results but it is not critical. In addition, a practical application of the sampling moiré method is presented that
involves a deflection measurement on a 10-meter-long crane. The experimental results demonstrate that submillimeter deflections
of the crane can be successfully detected. 相似文献
95.
In our study, the single‐use & eco‐friendly electrochemical sensor platform based on herbal silver nanoparticles (AgNPs) was developed for detection of mercury (II) ion (Hg2+). For this purpose, the surface of pencil graphite electrode (PGE) was modified with AgNPs and folic acid (FA), respectively. The concentrations of AgNPs and FA were firstly optimized by differential pulse voltammetry (DPV) to obtain an effective surface modification of PGE. Each step at the surface modification process was characterized by using cyclic voltammetry (CV) and electrochemical impedence spectroscopy (EIS). The limit of detection (LOD) for Hg2+ was estimated and found to be 8.43 μM by CV technique. The sensor presented an excellent selectivity for Hg2+ against to other heavy metal ions such as Ca2+, Cd2+, Cr3+, Cu2+, Mg2+, Ni2+, Pb2+, Zn2+, Co2+ and Mn2+. Moreover, a rapid, selective and sensitive detection of Hg2+ was successfully performed in the samples of tap water within 1 min. 相似文献
96.
Ece Aktas Jesús Jiménez-López Cristina Rodríguez-Seco Dr. Rajesh Pudi Dr. Manuel A. Ortuño Prof. Núria López Prof. Emilio Palomares 《Chemphyschem》2019,20(20):2702-2711
Truxene derivatives, due to their molecular structure and properties, are good candidates for the passivation of defects when deposited onto hybrid lead halide perovskite thin films. Moreover, their semiconductor characteristics can be tailored through the modification of their chemical structure, which allows-upon light irradiation- the interfacial charge transfer between the perovskite film and the truxene molecules. In this work, we analysed the use of the molecules as surface passivation agents and their use in complete functional solar cells. We observed that these molecules reduce the non-radiative carrier recombination dynamics in the perovskite thin film through the supramolecular complex formation between the Truxene molecule and the Pb2+ defects at the perovskite surface. Interestingly, this supramolecular complexation neither affect the carrier recombination kinetics nor the carriers collection but induced noticeable hysteresis on the photocurrent vs voltage curves of the solar cells under 1 sun illumination. 相似文献
97.
Research on substituted phenol degradations has received substantial attention. In this work, effective Co(II) and Cu(II) phthalocyanine complexes as catalysts were studied to degrade toxic phenols to harmless products. The effect of various process parameters, such as initial concentration of phenol, catalyst, oxygen sources, and temperature on the degradation reaction was investigated to achieve maximum degradation efficiency. The catalytic activities of Co(II) and Cu(II) phthalocyanines were evaluated for oxidation of phenolic compounds such as p-nitrophenol, o-chlorophenol, 2,3-dichlorophenol, and m-methoxyphenol. Co(II) phthalocyanine displayed good catalytic performance in degradation of 2,3-dichlorophenol to 2,3-dichlorobenzaldehyde and 2,3-dichloro-1,4-benzoquinone with the highest TON and TOF values within 3?h at 50?°C. The fate of catalyst during the degradation process was followed by UV–Vis spectroscopy. 相似文献
98.
Using the total radius of alkaline fluorides and sodium halides and their experimental total enthalpy values, absolute hydration
enthalpies of sodium and fluoride ions ( and ) were previously calculated. Also, by the help of data of sodium and fluoride ions for all alkaline metal ions and halides
absolute hydration enthalpies were determined.
相似文献
Sevda AyataEmail: |
99.
In-situ fatigue test on pre-fatigued aluminum single crystals and also in-situ tensile test of pre-fatigued copper-2 at.% aluminum alloy single crystals were carried out in an HVEM. In the Al crystals, forward and backward motion of dislocations, change of cell structures, formation of voids and crack propagation were directly observed in-situ by an HVEM under alternating stress. In the Cu-Al crystals, it was observed that slip occurred only in the part of the persistent slip bands during in-situ tensile deformation in an HVEM. 相似文献
100.
A new high‐performance blue to transmissive electrochromic material and use of silver nanowire network electrodes as substrates
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Janset Turan Ece Alpugan Serife Ozdemir Hacioglu Levent Toppare Ali Cirpan Husnu Emrah Unalan Gorkem Gunbas 《Journal of polymer science. Part A, Polymer chemistry》2017,55(10):1680-1686
Synthesis of a novel, high‐performance blue to transmissive switching electrochromic material is described. The polymer (P1) was prepared by both electrochemical ( P1E ) and chemical ( P1C ) means from the corresponding monomer. The electrochemically synthesized polymer ( P1E ) revealed 64% optical contrast change (on ITO) in the visible region and very fast switching times of 0.32 s (coloration) and 0.90 s (bleaching). On the other hand, the chemically synthesized, solution processable polymer ( P1C ) also showed a high optical contrast value (49%, on ITO) with very fast switching times of 0.86 s for coloration and 0.57 s for bleaching. These high optical contrast values coupled with fast switching times place these materials along with high‐performance blue to transmissive electrochromic polymers. Significantly, these improved characteristics were achieved by side chain engineering of a known, inferior blue to transmissive polymer, PBEBT. Towards fabrication of flexible electrochromic devices, the performance of P1C was also tested on silver nanowire network electrodes. Even though the full potential of the material could not be demonstrated, a good optical contrast of 24% was achieved using these electrodes. Under the same potential range allowed by silver nanowire network electrodes, P1C on ITO showed an optical contrast of 30%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1680–1686 相似文献