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41.
Ammonium dihydrogen phosphate (ADP) is a pioneer kind of nonlinear optical crystal. It can be used in various electro-optical, nonlinear optical applications. The pure and different weight percentage of Picric acid doped ADP single crystals are grown using the slow solvent evaporation technique at room temperature. The powder XRD study shows single phasic nature of all the grown crystals. The photoluminescence study suggests that the dopant causes defect in structure of ADP by virtue of vibration relaxation and self trapping exciton. The dielectric constant and the dielectric loss of all the grown crystals exhibited universal behaviour over frequency range considered. The Correlation Barrier Hopping and the Non Overlapping Small Polaron Tunnelling kind of conductivity mechanism are observed. The grain and grain boundary is indentified using the complex Impedance and the complex modulus spectroscopy. The third order nonlinear optical susceptibility is increased on doping the Picric acid in ADP crystals. The results are discussed here. 相似文献
42.
PurposeThe goal of this study was to develop a methodology to investigate the relationship between contractile function and hyperpolarized (HP) [1-13C]pyruvate metabolism in a small animal model. To achieve sufficient signal from HP 13C compounds, HP 13C MRS/MRSI has required relatively large infusion volumes relative to the total blood volume in small animal models, which may affect cardiac function.MethodsEight female Sprague Dawley rats were imaged on a 4.7T scanner with a dual tuned 1H/13C volume coil. ECG and respiratory gated k-t spiral MRSI and an IDEAL based reconstruction to determine [1-13C]pyruvate metabolism in the myocardium. This was coupled with 1H cine MRI to determine ventricular volumes and mechanical function pre- and post-infusion of [1-13C]pyruvate. For comparison to the [1-13C]pyruvate experiments, three female Sprague Dawley rats were imaged with 1H cine MRI to determine myocardial function pre- and post-saline infusion.ResultsWe demonstrated significant changes in cardiac contractile function between pre- and post-infusion of [1-13C]pyruvate. Specifically, there was an increase in end-diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF). Additionally, the ventricular vascular coupling ratio (VVCR) showed an improvement after [1-13C]pyruvate infusion, indicating increased systolic performance due to an increased arterial load. There was a moderate to strong relationship between the downstream metabolic conversion of pyruvate to bicarbonate and a strong relationship between the conversion of pyruvate to lactate and the cardiac mechanical function response.ConclusionThe infusion of [1-13C]pyruvate resulted in demonstrable increases in contractile function which was related to pyruvate conversion to bicarbonate and lactate. The combined effects of the infusion volume and inotropic effects of pyruvate metabolism likely explains the augmentation in myocardial mechanical function seen in these experiments. Given the relationship between pyruvate metabolism and contractile function observed in this study, this methodological approach may be utilized to better understand cardiac metabolic and functional remodeling in heart disease. 相似文献
43.
The polarization of a D-shaped fiber is modulated after immersing it in magnetic fluid(MF)and applying a magnetic field.Theoretical analysis predicts that magneto-optical dichroism of MF plays a key role in light polarization modulation.During light polarization modulation,the evanescent wave polarized parallel to the magnetic field has greater loss than its orthogonal component.Light polarization of a D-shaped fiber with a wide polished surface can be modulated easily.High concentration MF and a large magnetic field all have great ability to modulate light polarization. 相似文献
44.
Fedotova J. A. Kharchanka A. A. Fedotov A. K. Chichkov M. V. Malinkovich M. D. Konakov A. O. Vorobyova S. A. Kasiuk J. V. Gumiennik U. E. Kula M. Mitura-Nowak M. Maximenko A. A. Przewoźnik J. Kapusta Cz. 《Physics of the Solid State》2020,62(2):368-377
Physics of the Solid State - Electrodeposition of cobalt on monolayer graphene synthesized by chemical vapor deposition produces Co–CoO/graphene composite structures, which is accompanied by... 相似文献
45.
46.
《Particuology》2018
Silicoaluminophosphates (SAPOs) with different pore structures were synthesized through the implementation of polyethylene glycol (PEG) as a mesopores impregnation agent. Using PEGs with different molecular weights (MWs) and concentrations in the synthesis precursor, several samples were synthesized and characterized. Applying a PEG capping agent to the precursors led to the formation of tuned mesopores within the microporous matrix of the SAPO. The effects of the PEG molecular weight and PEG/Al molar ratio were investigated to maximize the efficiency of the catalyst in the methanol-to-olefin (MTO) process. Using PEG with a MW of 6000 resulted in the formation of both Zeolite Rho and chabazite structural frameworks (i.e., DNL-6 and SAPO-34). Pure SAPO-34 samples were successfully prepared using PEG with a MW of 4000. Our results showed that the PEG concentrations affect the porosity and acidity of the synthesized materials. Furthermore, the SAPO-34 sample synthesized with PEG (MW of 4000) and a PEG/Al molar ratio of 0.0125 showed a superior catalytic stability in the MTO reaction owing to the tuned bi-modal porosity and tailored acidity pattern. Finally, through reactivation experiments, it was found that the catalyst is stable even after several regeneration cycles. 相似文献
47.
Dr. Yong-Sheng Wei Dr. Liming Sun Miao Wang Dr. Jinhua Hong Dr. Lianli Zou Hongwen Liu Dr. Yu Wang Dr. Mei Zhang Dr. Zheng Liu Prof. Yinwei Li Prof. Satoshi Horike Prof. Kazu Suenaga Prof. Qiang Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16147-16156
Understanding the thermal aggregation behavior of metal atoms is important for the synthesis of supported metal clusters. Here, derived from a metal–organic framework encapsulating a trinuclear FeIII2FeII complex (denoted as Fe3) within the channels, a well-defined nitrogen-doped carbon layer is fabricated as an ideal support for stabilizing the generated iron nanoclusters. Atomic replacement of FeII by other metal(II) ions (e.g., ZnII/CoII) via synthesizing isostructural trinuclear-complex precursors (Fe2Zn/Fe2Co), namely the “heteroatom modulator approach”, is inhibiting the aggregation of Fe atoms toward nanoclusters with formation of a stable iron dimer in an optimal metal–nitrogen moiety, clearly identified by direct transmission electron microscopy and X-ray absorption fine structure analysis. The supported iron dimer, serving as cooperative metal–metal site, acts as efficient oxygen evolution catalyst. Our findings offer an atomic insight to guide the future design of ultrasmall metal clusters bearing outstanding catalytic capabilities. 相似文献
48.
Khadichakhan Rafikova Nil Ertekin Binbay Nermin Meriç Aygul Kerimkulova Alexey Zazybin Veysel Binbay Veysi Okumuş Cezmi Kayan Uğur Işik Nevin Arslan Murat Aydemir 《应用有机金属化学》2020,34(7):e5658
Four metal complexes, IL-OPPh2-Ru-p-cymene (3) , IL-OPPh2-Ru-benzene (4) , IL-OPPh2-Ir-Cp* (5) , IL-OPPh2-Rh-COD (6) , have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors. 相似文献
49.
Dr. Yukun Zhu Chunxiao Lv Zhuocheng Yin Prof. Jun Ren Prof. Xianfeng Yang Prof. Chung-Li Dong Prof. Hongwei Liu Dr. Rongsheng Cai Yu-Cheng Huang Prof. Wolfgang Theis Prof. Shaohua Shen Prof. Dongjiang Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):878-883
Red phosphorus is a promising photocatalyst with wide visible-light absorption up to 700 nm, but the fast charge recombination limits its photocatalytic hydrogen evolution reaction (HER) activity. Now, [001]-oriented Hittorf's phosphorus (HP) nanorods were successfully grown on polymeric carbon nitride (PCN) by a chemical vapor deposition strategy. Compared with the bare PCN and HP, the optimized PCN@HP hybrid exhibited a significantly enhanced photocatalytic activity, with HER rates reaching 33.2 and 17.5 μmol h−1 from pure water under simulated solar light and visible light irradiation, respectively. It was theoretically and experimentally indicated that the strong electronic coupling between PCN and [001]-oriented HP nanorods gave rise to the enhanced visible light absorption and the greatly accelerated photoinduced electron–hole separation and transfer, which benefited the photocatalytic HER performance. 相似文献