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排序方式: 共有256条查询结果,搜索用时 46 毫秒
251.
This work reports on the synthesis and photophysical properties of novel unsymmetrically substituted monocarboxy magnesium (MgPc, 3), aluminum (ClAlPc, 4) and unmetallated (H2Pc, 5) phthalocyanines. Magnesium phthalocyanine (3) was converted into water soluble quaternized derivative (QMgPc, 6) by reaction with methyl iodide. The synthesized phthalocyanines were characterized by IR, UV-Vis, NMR, mass spectrometry and elemental analyses. Photophysical and photochemical studies were carried out in order to determine the potential of the complexes as photosensitizers for use in photodynamic therapy. Triplet quantum yields ranged from 0.37 to 0.40 and triplet lifetimes from 110 to 140 μs in DMSO. 相似文献
252.
M. Yasin S. W. Harun Kusminarto Karyono D. Lelono Samian A. H. Zaidan H. Ahmad 《Laser Physics》2010,20(4):824-829
The performances of the fiber optic-based displacement sensor with reflective and transmitting techniques were investigated.
The effects of axial displacement on the detected voltage were investigated for different tilting angles of the reflective
and receiving fibers. Three types of light sources were used, yellow and red He-Ne including a green pointer laser at peak
wavelengths of 594, 633, and 533 nm correspondingly. The highest sensitivity and resolution were obtained at 0.0017 mV/μm
and 4 μm, respectively with the employment of a 594 nm laser as the light source. These were attributed to the output power
and beam quality of the laser which was the highest. The tilting angles didn’t change the sensitivity and resolution of the
sensors in both setups. The widest linear range was obtained at 2410 μm with the transmitting technique. The simplicity of
the design, high degree of sensitivity, linear range, non-contact measurement and low cost fabrication make it suitable for
industrially-orientated applications that include control and micro-displacement in the hazardous region. 相似文献
253.
Shuaib Urooj Hussain Tousif Ahmad Riaz Imranullah M. Amjad Muhammad Yasin Amna Shakir Imran Kang Dae Joon 《Journal of Solid State Electrochemistry》2023,27(3):715-725
Journal of Solid State Electrochemistry - Nowadays, metal hexacyanoferrate/metal oxide composites have attracted intense interest as an electrode material for supercapacitor applications due to... 相似文献
254.
255.
Asif Hayat Muhammad Sohail Atef El Jery Khadijah M. Al-Zaydi Khaled F Alshammari Javid Khan Hamid Ali Zeeshan Ajmal T. A. Taha Israf Ud Din Rashid Altamimi Mahmoud Ali Hussein Yas Al-Hadeethi Yasin Orooji Mohd Zahid Ansari 《Chemical record (New York, N.Y.)》2023,23(5):e202200171
Graphitic carbon nitride (g-C3N4) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3N4. The dimensions of g-C3N4 may impact the field of electronics confinement; as a consequence, g-C3N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3N4, there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3N4. Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3N4. Emphasis is given to the practical design and development of g-C3N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium–sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3N4 for fuel transformation and retention activities are explored. 相似文献
256.
In this work, the role of spin-orbit coupling (SOC) in ATl3 (A = Ca, Y, La, and Th) and La3Tl is investigated by theoretical investigation of their structural, electronic, elastic, mechanical, phonon, and electron–phonon interaction properties. The effect of SOC on the electronic band structures of these compounds is that some of the degeneracies at the high symmetry points that would exist in a scalar relativistic calculation without SOC are removed by considering this coupling. The replacement of La and Tl atoms in LaTl3 increases the value of the density of states at the Fermi level N() by a factor of 2.1. Furthermore, this replacement makes almost all phonon modes in La3Tl softer than those in LaTl3. Both softer phonon modes and higher N() make the electron–phonon interaction in La3Tl much stronger than in LaTl3. The presence of SOC increases the values of LaTl3 by 34% (from 1.151 to 1.542 K) and of ThTl3 by 65% (from 0.479 to 0.793 K), resulting in good agreement with the corresponding experimental values of 1.63 and 0.87 K. The inclusion of SOC also improves the agreement with the experiment for values of CaTl3, YTl3, and La3Tl. 相似文献