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101.
Seda Ünlü Göknur Yaşa Atmaca Fikriye Tuncel Elmalı Ali Erdoğmuş 《Photochemistry and photobiology》2023,99(5):1233-1239
Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ = 0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine ( 2a ), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine ( 2b ) in photochemical study) reached to ΦΔ = 0.98 for 2a , 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield. 相似文献
102.
Sikandar Azam Muhammad Imran Amin Ur Rahman Asif Nadeem Riadh Neffati 《International journal of quantum chemistry》2023,123(3):e27025
The optical properties, electronic charge density, electronic structure of the new layered selenides materials, BaGdCuSe3, CsUCuSe3, CsZrCuSe3, and CsGdZnSe3 compounds have been calculated by using the full potential and linear augmented plane wave (FP-LAPW) methods as applied in the WIEN2k package, which is based on the density functional theory. The ALnMSe3 compound's structure of these was (A = Cs, Ba; Ln = Zr, Gd, U; M = Cu, Zn) is composed of (n = 1, 2) layers, which might be separated by A atoms. It is to be observed that there is strong hybridization between the s, p, and d states of Zr, Gd, and Cu atoms. Around the gadolinium atom, the charge density contours are completely circular, but the Gadolinium “Gd” atom shows an ionic nature. To calculate the refractive index, we used Kramer's Kronig correlations with the imaginary part dielectric function. The decrease in the refractive index is due to the lack of probability for direct excitation of the electrons, resulting in a loss of energy. The value of the static refractive index for all reference compounds is about 1.75–2.25, which is indication that the material used in optoelectronic devices. 相似文献
103.
Hassan Nabizadeh Bahareh Feyzi Amir Ahmad Salarian Seyed Reza Abtahi Ali Mohammadi Zahra Hami 《Electroanalysis》2023,35(1):e202200022
The development of selective and simple methods for the determination of different analytes is of great interest. This is the first time to show the applicability of graphene oxide-chitosan (GO-CS) nanocomposite for designing an electrochemical nanosensor for determination of Amlodipine, Valsartan, and Hydrochlorothiazide, simultaneously. Differential pulse voltammetrics current of AML, HCT, and VAL increased linearly in the ranges of 0.1–110, 0.1–110, and 1–230 μM with LOD of 5.5×10−2, 3.5×10−2 and 8.6×10−2 μM, respectively. Finally, GO-CS/GCE was used for the detection of these drugs in commercial tablets and compared with the reference method (HPLC). 相似文献
104.
Dr. David F. León Rayo Ali Mansour Dr. Wenbin Wu Dr. Benjamin N. Bhawal Prof. Fabien Gagosz 《Angewandte Chemie (International ed. in English)》2023,62(3):e202212893
Direct C−H bond functionalization is a useful strategy for the straightforward formation of C−C and C−Heteroatom bonds. In the present work, a unique approach for the challenging electrophilic Au-catalyzed α-C−H bond functionalization of tertiary amines is presented. Electronic, steric and conformational synergistic effects exerted by the use of a malonate unit in the substrate were key to the success of this transformation. This new reactivity was applied to the synthesis of tetrahydro-γ-carboline products which, under oxidative conditions, could be converted into valuable structural motifs found in bioactive alkaloid natural products. 相似文献
105.
Ali Azmy Shunran Li Giasemi K. Angeli Claire Welton Parth Raval Min Li Nourdine Zibouche Lukasz Wojtas G. N. Manjunatha Reddy Peijun Guo Pantelis N. Trikalitis Ioannis Spanopoulos 《Angewandte Chemie (International ed. in English)》2023,62(12):e202218429
In this work we report a strategy for generating porosity in hybrid metal halide materials using molecular cages that serve as both structure-directing agents and counter-cations. Reaction of the [2.2.2] cryptand (DHS) linker with PbII in acidic media gave rise to the first porous and water-stable 2D metal halide semiconductor (DHS)2Pb5Br14. The corresponding material is stable in water for a year, while gas and vapor-sorption studies revealed that it can selectively and reversibly adsorb H2O and D2O at room temperature (RT). Solid-state NMR measurements and DFT calculations verified the incorporation of H2O and D2O in the organic linker cavities and shed light on their molecular configuration. In addition to porosity, the material exhibits broad light emission centered at 617 nm with a full width at half-maximum (FWHM) of 284 nm (0.96 eV). The recorded water stability is unparalleled for hybrid metal halide and perovskite materials, while the generation of porosity opens new pathways towards unexplored applications (e.g. solid-state batteries) for this class of hybrid semiconductors. 相似文献
106.
Dr. Huanhuan Shi Prof. Mengmeng Li Shuai Fu Dr. Christof Neumann Dr. Xiaodong Li Dr. Wenhui Niu Yunji Lee Prof. Mischa Bonn Dr. Hai I. Wang Prof. Andrey Turchanin Dr. Ali Shaygan Nia Dr. Sheng Yang Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303929
Two-dimensional van der Waals heterostructures (2D vdWHs) have recently gained widespread attention because of their abundant and exotic properties, which open up many new possibilities for next-generation nanoelectronics. However, practical applications remain challenging due to the lack of high-throughput techniques for fabricating high-quality vdWHs. Here, we demonstrate a general electrochemical strategy to prepare solution-processable high-quality vdWHs, in which electrostatic forces drive the stacking of electrochemically exfoliated individual assemblies with intact structures and clean interfaces into vdWHs with strong interlayer interactions. Thanks to the excellent combination of strong light absorption, interfacial charge transfer, and decent charge transport properties in individual layers, thin-film photodetectors based on graphene/In2Se3 vdWHs exhibit great promise for near-infrared (NIR) photodetection, owing to a high responsivity (267 mA W−1), fast rise (72 ms) and decay (426 ms) times under NIR illumination. This approach enables various hybrid systems, including graphene/In2Se3, graphene/MoS2 and graphene/MoSe2 vdWHs, providing a broad avenue for exploring emerging electronic, photonic, and exotic quantum phenomena. 相似文献
107.
Abdul Malek Yanrong Xue Xu Lu 《Angewandte Chemie (International ed. in English)》2023,62(40):e202309854
In the pursuit of long-term stability for oxygen evolution reaction (OER) in seawater, retaining the intrinsic catalytic activity is essential but has remained challenging. Herein, we developed a NixCryO electrocatalyst that manifested exceptional OER stability in alkaline condition while improving the activity over time by dynamic self-restructuring. In 1 M KOH, NixCryO required overpotentials of only 270 and 320 mV to achieve current densities of 100 and 500 mA cm−2, respectively, with excellent long-term stability exceeding 475 h at 100 mA cm−2 and 280 h at 500 mA cm−2. The combination of electrochemical measurements and in situ studies revealed that leaching and redistribution of Cr during the prolonged electrolysis resulted in increased electrochemically active surface area. This eventually enhanced the catalyst porosity and improved OER activity. NixCryO was further applied in real seawater from the Red Sea (without purification, 1 M KOH added), envisaging that the dynamically evolving porosity can offset the adverse active site-blocking effect posed by the seawater impurities. Remarkably, NixCryO exhibited stable operation for 2000, 275 and 100 h in seawater at 10, 100 and 500 mA cm−2, respectively. The proposed catalyst and the mechanistic insights represented a step towards realization of non-noble metal-based direct seawater splitting. 相似文献
108.
Chathuranga S. L. Rathnamalala Selena Hernandez Dr. Melissa Y. Lucero Chelsea B. Swartchick Dr. Abdul Kalam Shaik Prof. Dr. Nathan I. Hammer Amanda K. East Prof. Dr. Steven R. Gwaltney Prof. Dr. Jefferson Chan Prof. Dr. Colleen N. Scott 《Angewandte Chemie (International ed. in English)》2023,62(13):e202214855
Shortwave infrared (SWIR) dyes are characterized by their ability to absorb light from 900 to 1400 nm, which is ideal for deep tissue imaging owing to minimized light scattering and interference from endogenous pigments. An approach to access such molecules is to tune the photophysical properties of known near-infrared dyes. Herein, we report the development of a series of easily accessible (three steps) SWIR xanthene dyes based on a dibenzazepine donor conjugated to thiophene ( SCR-1 ), thienothiophene ( SCR-2 ), or bithiophene ( SCR-3 ). We leverage the fact that SCR-1 undergoes a bathochromic shift when aggregated for in vivo studies by developing a ratiometric nanoparticle for NO ( rNP-NO ), which we employed to successfully visualize pathological levels of nitric oxide in a drug-induced liver injury model via deep tissue SWIR photoacoustic (PA) imaging. Our work demonstrates how easily this dye series can be utilized as a component in nanosensor designs for imaging studies. 相似文献
109.
Dr. Ali Munaim Yousif Stefania Colarusso Elisabetta Bianchi 《European journal of organic chemistry》2023,26(12):e202300099
Peptide drug discovery often benefits from the large structural diversity permitted by unnatural amino acids (UAAs). Indeed, numerous approved peptide drugs include UAAs in their sequences. Therefore, innovative chemical approaches either to synthesize UAAs or to allow late-stage functionalization of peptides are emerging themes in peptide drug discovery. Thanks to the recent advances in deaminative strategies using alkylpyridiniums salts, often referred to as Katritzky salts, a variety of radical alkylation methods have been developed. In recent years the use of Katritzky salts have become popular in peptide chemistry due to their ease of preparation from a primary amine, which is a predominant functional group in amino acids. This review highlights the progress that has been made by using Katritzky salts in the synthesis of UAAs, late-stage peptide functionalization, and peptide macrocyclization. 相似文献
110.
Shaik Inayath Basha Atta Ur Rehman Hammad R. Khalid Md. Abdul Aziz Jung-Hoon Kim 《Chemical record (New York, N.Y.)》2023,23(10):e202300054
Three-dimensional (3D) geopolymer printing (3DGP) technology is a rapidly evolving digital fabrication method used in the construction industry. This technology offers significant benefits over 3D concrete printing in terms of energy saving and reduced carbon emissions, thus promoting sustainability. 3DGP technology is still evolving, and researchers are striving to develop high-performance printable materials and different methods to improve its robustness and efficiency. Carbon-based nanomaterials (CBNs) with beneficial properties have a wide range of applications in various fields, including as concrete/geopolymer systems in construction. This paper comprehensively reviews the research progress on carbon-based nanomaterials (CBNs) used to develop extrusion-based 3D geopolymer printing (3DGP) technology, including dispersion techniques, mixing methods, and the materials′ performance. The rheological, mechanical, durability, and other characteristics of these materials are also examined. Furthermore, the existing research limitations and the prospects of using 3DGP technology to produce high-quality composite mixtures are critically evaluated. 相似文献