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Maryam Oudi Kazem Sanchooli Tazeh Nourallah Hazeri Maryam Fatahpour Raheleh Ahmadi 《中国化学会会志》2019,66(12):1721-1728
In the present work, the catalytic activity of quinolinic acid (QUIN) was studied for the synthesis of spirochromene and pyranopyrazole derivatives from readily available materials. The salient features of these one‐pot multicomponent protocols are the clean reaction profile, easy isolation of products, no chromatographic separation techniques, high efficiency, short reaction time, and high yield of products plus using QUIN as a new, inexpensive, commercially available, and efficient organocatalyst. 相似文献
93.
Akram Hosseinian Arezoo Gharachorloo Tarlan Mohazzab Lighvani Parvaneh Delir Kheirollahi Nezhad Esmail Vessally 《应用有机金属化学》2018,32(10)
It has been previously reported that the recently synthesized hexa‐peri‐hexabenzocoronene (HBC) nanographene cannot detect toxic chloropicrin (CP) gas. To overcome this problem, we examined the effect of Al doping and applying an electric field on the sensitivity of HBC towards CP gas by means of density functional theory calculations. We found that the Al‐doping process significantly increases the adsorption energy of CP gas from ?7.1 to ?39.9 kcal mol?1 but decreases the sensitivity of HBC. By applying an electric field, the HBC is polarized with two different electrostatic potentials on its different surfaces, which increases the adsorption energy. By increasing the electric field strength, the adsorption energy and electronic sensitivity of HBC are increased. We predicted that in the presence of an electric field of about ?0.025 au, HBC can act as an electronic senor or a work function‐type sensor with a short recovery time. At this field, the electrical conductivity of HBC is significantly increased on CP adsorption which generates an electrical signal. Increasing the electric field to higher intensities is not favourable because of increasing recovery times, and decreasing it to lower intensities reduces the sensitivity of HBC. 相似文献
94.
Maryam Taherzadeh Raheleh Afzali Marek Nečas 《Phosphorus, sulfur, and silicon and the related elements》2017,192(8):936-944
The hydrogen bond pattern of N-(4-methoxybenzoyl)-N′,N″-bis(4-methylbenzyl)-phosphoric triamide, C24H28N3O3P, (I), was investigated. In the crystal structure, the molecules are aggregated through NCP―H···O═P and NP―H···O═C hydrogen bonds in a one-dimensional arrangement parallel to the c axis (NCP is the nitrogen atom in the C(O)NHP(O) segment and NP stands for the two other nitrogen atoms bonded to the P atom). There is also a novel NP?H···π hydrogen bond in the crystal which extends the aggregation of the molecules to a two-dimensional array parallel to the bc plane. A Cambridge Structural Database (CSD, version 5.37, Feb 2016) analysis shows that the N―H···π hydrogen bond was not observed in any of 156 [RC(O)NH]P(O)[NR1R2]2 (R1 ≠ H, R2 = H or ≠ H) phosphoric triamide structures reported so far. The theoretical calculations at the B3LYP/6-311G** level of theory (DFT, AIM, and NBO) were performed to evaluate the strengths of NCP―H···O═P, NP―H···O═C and NP―H···π hydrogen bonds, considering two-aggregate molecular assemblies containing these hydrogen bonds. The calculations on the title compound suggest that the intermolecular NCP―H···O═P hydrogen bond is stronger than NP―H···O═C and NP―H···π interactions. The hydrogen bond strength was investigated by NBO, topological analysis, geometry calculation, Hirshfeld surface analysis and experimental spectroscopic results, which are in agreement with each other. 相似文献
95.
Spherical spline quaternion interpolation has been done on sphere in Euclidean space using quaternions. In this paper, we have done the spline split quaternion interpolation on hyperbolic sphere in Minkowski space using split quaternions and metric Lorentz. This interpolation curve is called spherical spline split quaternion interpolation in Minkowski space (MSquad). 相似文献
96.
Golnaz Sadoughi Raheleh Mohammadpour Azam Irajizad Nima Taghavinia Shabnam Dadgostar Mahmoud Samadpour Fariba Tajabadi 《Current Applied Physics》2013,13(2):371-376
The photoanodes of solid state dye sensitized solar cells (ss-DSCs) embedded with different contents of TiO2 hollow spheres (HSs) were prepared and the photovoltaic performances were systematically characterized. TiO2 hollow spheres were synthesized by a facile sacrificial templating method, grounded and added in different ratios to TiO2 nanoparticle (NP) paste, from which composite HS/NP electrodes were fabricated. The composite photoanodes include hollow spheres of 300–700 nm with enhanced light scattering characteristics in visible range which leads to improved light absorption in conventional thin film electrodes of ss-DSC. By optimizing the amount of HSs in the paste, 40% improvement in efficiency was obtained in comparison to ss-DSC utilized pure NP electrodes. By increasing the fraction of HSs in the electrode the current density increased by 56% (from 2.5 to 3.9 mA cm?2). The improved photovoltaic performance of ss-DSC is primarily due to different morphology and altered charged trap distribution in HSs in comparison to NP which leads to significant enhancement in electron transport time and electron lifetime as well as charge collection efficiency and light absorption properties. 相似文献
97.
Sara Alesheikh Nasser Shahtahmassebi Mahmood Rezaee Roknabadi Raheleh Pilevar Shahri 《Physics letters. A》2018,382(8):595-600
The importance of applying DNA sequencing in different fields, results in looking for fast and cheap methods. Nanotechnology helps this development by introducing nanostructures used for DNA sequencing. In this work we study the interaction between zigzag silicene nanoribbon and DNA nucleobases using DFT and non equilibrium Green's function approach, to investigate the possibility of using zigzag silicene nanoribbons as a biosensor for DNA sequencing. 相似文献
98.
Tppz (2,3,5,6-tetrakis(2-pyridyl)pyrazine) complexes [Rh(tppz)(bpy)Cl][PF6]2.acetylacetone (bpy = 2,2′-bipyridine) and [{CdCl2}2(μ-tppz)].ethylene glycol have been synthesized and characterized by elemental analyses, IR, 1H NMR, cyclic voltammetry, photoluminescence and electronic spectral studies. Solid state structures of both complexes have been determined by single-crystal X-ray crystallography. The structural determination shows that the dinuclear Cd(II) complex, [{CdCl2}2(μ-tppz)], is a 1D coordination polymer. An ORTEP drawing of [Rh(tppz)(bpy)Cl][PF6]2.acetylacetone shows that the coordination geometry around the Rh(III) center is a distorted octahedron. [{CdCl2}2(μ-tppz)] displays intraligand 1(π–π*) fluorescence and can potentially serve as a photoactive material. For the mononuclear Rh(III) complex, only a two-electron reduction process occurs at the metal with the elimination of Cl− ligand. The emission of this complex is assigned as πd* phosphorescence. 相似文献
99.
First principles study and comparison of vibrational and thermodynamic properties of XBi(X= In,Ga, B,Al) 下载免费PDF全文
In the present work, vibrational and thermodynamic properties of XBi(X = B, Al, Ga, In) compounds are compared and investigated. The calculation is carried out using density functional theory(DFT) within the generalized gradient approximation(GGA) in a plane wave basis, with ultrasoft pseudopotentials. The lattice dynamical properties are calculated using density functional perturbation theory(DFPT) as implemented in Quantum ESPRESSO(QE) code. Thermodynamic properties involving phonon density of states(DOS) and specific heat at constant volume are investigated using quasiharmonic approximation(QHA) package within QE. The phonon dispersion diagrams for InBi, GaBi, BBi, and AlBi indicate that there is no imaginary phonon frequency in the entire Brillouin zone, which proves the dynamical stability of these materials. BBi has the highest thermal conductivity and InBi has the lowest thermal conductivity. AlBi has the largest and GaBi has the smallest reststrahlen band which somehow suggests the polar property of XBi materials. The phonon gaps for InBi, GaBi, BBi and AlBi are about 160 cm~(-1), 150 cm~(-1), 300 cm~(-1), and 150 cm~(-1), respectively. For all compounds,the three acoustic modes near the gamma point have a linear behavior. C_V is a function of T~3 at low temperatures while for higher temperatures it asymptotically tends to a constant as expected. 相似文献
100.
Moradi Ahmad Toghraie Davood Isfahani Amir Homayoon Meghdadi Hosseinian Ali 《Journal of Thermal Analysis and Calorimetry》2019,137(5):1797-1807
Journal of Thermal Analysis and Calorimetry - This paper presents the results of an experimental investigation on the heat transfer characteristics of multi-walled carbon nanotube aqueous... 相似文献