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531.
Amination of phenylene moieties in crystal-like mesoporous silica hybridized with phenylene is successfully achieved with close to 28% conversion of phenylene by a two-step chemical transformation process while preserving both the ordered mesostructure and crystal-like molecular scale periodicity of the parent material. 相似文献
532.
Sol-gel process has gained tremendous attention in past decades for the preparation of pure and composite material for numerous
applications. Organically modified sol-gel glasses (ormosils) have hybrid properties of rigid inorganic silica matrix and
organic functionalities. Ormosils provide ambient environment for bio-molecules encapsulation and such systems have been used
widely for biosensor applications. Biological elements including enzymes, antibodies, antigens, DNA, whole cells, tissues,
proteins, biologically derived material, and biomimetic materials provide the possibility of biological recognition to the
device and transducer to detect the biological signals with the help of associated electronics and software to amplify these
signals into a readable form for the user. In this review we report on the formation of sol-gel based composite materials
primarily on ormosil along with carbon nano tubes, metal nano particles, mediators, inorganic complexes, polymers, ionomers
and biological materials and cite the electrochemical sensor/biosensor system based on it. 相似文献
533.
Viyannalage L Lee V Dennis RV Kapoor D Haines CD Banerjee S 《Chemical communications (Cambridge, England)》2012,48(42):5169-5171
Anisotropic Mg nanowires have been successfully prepared by electrocrystallization of Grignard's reagents thought to proceed via a modified faces, steps, and kinks (FSK) mechanism. Mg nanoparticles with roughly hexagonal shapes have also been obtained via chemical reduction of the same Grignard's reagents. 相似文献
534.
Dinesh Kumar Inder Pal Singh Kapoor Gurdip Singh Nidhi Goel Udai Pratap Singh 《Journal of Thermal Analysis and Calorimetry》2012,107(1):325-334
Recent work has described the preparation and characterization of the two complexes [Fe2(C10H8N2)4O(OH2)2](NO3)4 and [Co(C10H8N2)3]2[Co(OH2)6]·7(OH2) (NO3)8 in which both the nitrogen atoms of 2,2′-bipyridine are directly bonded with the metals. Their structures were determined
by single-crystal X-ray diffraction at 296 K. Thermolysis of these complexes has been detailed by the use of TG–DTA and ignition
delay measurements. Kinetics of thermal decomposition has also been established. Model free isoconversional and model fitting
kinetic approaches have been applied to isothermal TG data for the decomposition of these complexes. 相似文献
535.
Mehmet Baha Karan Aydın Ulucan Mustafa Kaya 《Central European Journal of Operations Research》2013,21(2):479-494
Our paper presents a comparative study applying logistic regression and multiple criteria decision analysis tools to the operations of wholesalers to assess the credit risk of their retailers using payment history data and to cluster the risky customers by ranking their risk levels. Our sample comprises approximately 6,000 retailer customers and 600.000 transactions of one of the major wholesalers of Turkey. Our findings emphasize the importance of using payment history and some non-financial factors data for predicting the creditworthiness of a firm. 相似文献
536.
Xinlin Li Sreehari Surendran Rajasree Dr. Venkatesh Gude Karan Maindan Prof. Dr. Pravas Deria 《Angewandte Chemie (International ed. in English)》2023,62(22):e202219046
Traditional MOF e-CRR, constructed from catalytic linkers, manifest a kinetic bottleneck during their multi-electron activation. Decoupling catalysis and charge transport can address such issues. Here, we build two MOF/e-CRR systems, CoPc@NU-1000 and TPP(Co)@NU-1000, by installing cobalt metalated phthalocyanine and tetraphenylporphyrin electrocatalysts within the redox active NU-1000 MOF. For CoPc@NU-1000, the e-CRR responsive CoI/0 potential is close to that of NU-1000 reduction compared to the TPP(Co)@NU-1000. Efficient charge delivery, defined by a higher diffusion (Dhop=4.1×10−12 cm2 s−1) and low charge-transport resistance ( =59.5 Ω) in CoPC@NU-1000 led FECO=80 %. In contrast, TPP(Co)@NU-1000 fared a poor FECO=24 % (Dhop=1.4×10−12 cm2 s−1 and =91.4 Ω). For such a decoupling strategy, careful choice of the host framework is critical in pairing up with the underlying electrochemical properties of the catalysts to facilitate the charge delivery for its activation. 相似文献
537.
Anton A. Peshkov Elena Jordan Markus Kromrey Karan K. Mehta Tanja E. Mehlstäubler Andrey Surzhykov 《Annalen der Physik》2023,535(9):2300204
Photoexcitation of trapped ions by Hermite–Gaussian (HG) modes from guided beam structures is proposed and investigated theoretically. In particular, simple analytical expressions for the matrix elements of induced atomic transitions are derived that depend both on the parameters of HG beams and on the geometry of an experiment. By using these general expressions, the electric octupole (E3) transition is investigated in an Yb+ ion, localized in the low–intensity center of the HG10 and HG01 beams. It is shown how the corresponding Rabi frequency can be enhanced by properly choosing the polarization of incident light and the orientation of an external magnetic field, which defines the quantization axis of a target ion. The calculations, performed for experimentally feasible beam parameters, indicate that the achieved Rabi frequencies can be comparable or even higher than those observed for the conventional Laguerre–Gaussian (LG) modes. Since HG-like modes can be relatively straightforwardly generated with high purity and stability from integrated photonics, these results suggest that they may form a novel tool for investigating highly-forbidden atomic transitions. 相似文献