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排序方式: 共有349条查询结果,搜索用时 31 毫秒
1.
The booming development of organometal halide perovskites in recent years has prompted the exploration of morphology‐control strategies to improve their performance in photovoltaic, photonic, and optoelectronic applications. However, the preparation of organometal halide perovskites with high hierarchical architecture is still highly challenging and a general morphology‐control method for various organometal halide perovskites has not been achieved. A mild and scalable method to prepare organometal halide perovskites in inverse opal morphology is presented that uses a polystyrene‐based artificial opal as hard template. Our method is flexible and compatible with different halides and organic ammonium compositions. Thus, the perovskite inverse opal maintains the advantage of straightforward structure and band gap engineering. Furthermore, optoelectronic investigations reveal that morphology exerted influence on the conducting nature of organometal halide perovskites. 相似文献
2.
Polat Narin Ece Kutlu-Narin Gokhan Atmaca Beyza Sarikavak-Lisesivdin Sefer B. Lisesivdin Ekmel Ozbay 《Surface and interface analysis : SIA》2022,54(5):576-583
Metal–organic chemical vapor deposition (MOCVD) is one of the best growth methods for GaN-based materials as well-known. GaN-based materials with very quality are grown the MOCVD, so we used this growth technique to grow InAlN/GaN and AlN/GaN heterostructures in this study. The structural and surface properties of ultrathin barrier AlN/GaN and InAlN/GaN heterostructures are studied by X-ray diffraction (XRD) and atomic force microscopy (AFM) measurements. Screw, edge, and total dislocation densities for the grown samples have been calculated by using XRD results. The lowest dislocation density is found to be 1.69 × 108 cm−2 for Sample B with a lattice-matched In0.17Al0.83N barrier. The crystal quality of the studied samples is determined using (002) symmetric and (102) asymmetric diffractions of the GaN material. In terms of the surface roughness, although reference sample has a lower value as 0.27 nm of root mean square values (RMS), Sample A with 4-nm AlN barrier layer exhibits the highest rough surface as 1.52 nm of RMS. The structural quality of the studied samples is significantly affected by the barrier layer thickness. The obtained structural properties of the samples are very important for potential applications like high-electron mobility transistors (HEMTs). 相似文献
3.
Natural convection and conduction heat transfer in open shallow cavities with bounding walls 总被引:1,自引:0,他引:1
A numerical study has been carried out on inclined open shallow cavities, which are formed by a wall and horizontal fins. Constant heat flux is applied on the surface of the wall inside the cavity while its other surface was kept isothermal. The wall and the fins are conductive. Conjugate heat transfer by natural convection and conduction is studied by numerically solving equations of mass, momentum and energy. Streamlines and isotherms are produced, heat and mass transfer is calculated. A parametric study is carried out using following parameters: Rayleigh number from 106 to 1012, conductivity ratio from 1 to 60, open cavity aspect ratio from 1 to 0.125, dimensionless end wall thickness from 0.05 to 0.20, horizontal walls from 0.01 to 0.15 and inclination of the end wall from 90° to 45°. It is found that the volume flow rate and Nusselt number are a decreasing function of the cavity aspect ratio, horizontal fin thickness and conductivity ratio. They are an increasing function of end wall thickness and inclination angle, except in the latter case optima exist at high Rayleigh numbers. 相似文献
4.
A novel 3-(substituted benzylideneamino)-7-chloro-2-phenyl quinazoline-4(3H)-one (7–27) has been synthesized and characterised by IR, 1H NMR, 13C NMR spectroscopy, and elemental analysis. We changed the methodology for the synthesis of 3-amino 7-chloro-2-phenyl quinazolin-4(3H)-one 6 to fusion reaction at 250 °C, instead of using solvent, to avoid the problem of ring opening, which is commonly observed while synthesizing quinazolines from benzoxazinone. NCI selected, 7-chloro-3-{[(4-chlorophenyl) methylidene] amino}-2-phenylquinazolin-4(3H)-one 12, with GI50 value of ?5.59 M, TGI value of ?5.12 M, and LC50 value of ?4.40 M showed remarkable activity against CNS SNB-75 Cancer cell line. Rational approach and QSAR techniques enabled the understanding of the pharmacophoric requirement for 2,3,7-tri substituted quinazoline derivatives to inhibit EGFR-tyrosine kinase as antitumor agents and could be used as an excellent framework in this field that may lead to discovery of potent anti tumor agent. 相似文献
5.
In this paper,we consider the global existence of solutions for the Cauchy problem of the generalized sixth order bad Boussinesq equation.Moreover,we show that the supremum norm of the solution decays algebraically to zero as(1+t)(1/7)when t approaches to infnity,provided the initial data are sufciently small and regular. 相似文献
6.
We demonstrate a switchable Q-switched and mode-locked erbium-doped fiber laser (EDFL) operating in the L-band region using the nonlinear polarization rotation effect. The switching operation is achieved by controlling intensity-dependent loss using a polarization controller. In Q-switching mode, the EDFL produces a pulse train with a repetition rate of 21.1 kHz, pulse width of 7.7 #s, and pulse energy of 13.6 nJ. The EDFL also generates a multi-wavelength comb with a very narrow and constant wavelength spacing of 0.045 nm and optical signal-to-noise ratio of at least l0 dB. During mode locking, the EDFL produces stretched pulses with 3-dB bandwidth of 26.2 nm, pulse width of 350 fs, repetition rate of 2.38 MHz, and pulse energy of 48.56 pJ. 相似文献
7.
Harun Muhammad Arif Bin Gunnasegaran Prem A./L. Sidik Nor Azwadi Che Beriache M’hamed Ghaderian Javad 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1435-1449
Journal of Thermal Analysis and Calorimetry - High heat generation from electronic devices needs to cool down properly to prevent overheating. Loop heat pipe (LHP) is one of the excellent cooling... 相似文献
8.
9.
Cesme Mustafa Polat Duygu Senel Pelin Golcu Aysegul 《Russian Journal of Electrochemistry》2019,55(4):281-290
Russian Journal of Electrochemistry - In this study, a new biosensor for amisulpride (ASP) determination is defined. The interaction between ASP and fish sperm double-stranded DNA (FSdsDNA) was... 相似文献
10.
Ratiometric fluorescent chemosensors based on the position of ring annulation of the naphthol–thiazole moiety for quantification of zinc ions in aqueous ethanol were synthesized and investigated. It was found that sensor 3 exhibited a remarkably large red shift of 140 nm in emission upon complexation with Zn2+. A TD-B3LYP/6-31G (d,p) calculation was performed to characterize the nature of the fluorescence behavior of sensor 3 upon Zn2+ complexation. The combination of experimental and computational analyses provides a more complete understanding of the molecular level origin of these unique photophysical properties of this type of chemosensor. 相似文献