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1.
In this paper, a quantum cascade laser (QCL) design is proposed based on GaAs/AlGaAs material system, which simultaneously operates at three widely separated wavelengths ( and ). In the design, all the wavelength radiations are achieved by the engineering of the electronic spectrum via the quantum-well widths and the applied electric field in a single active region within a same waveguide. The mid-infrared (mid-IR) wavelengths are obtained by adoption a dual-upper-state active region, and the proposed design aims to use both the mid-IR radiations as the coherent deriving fields to populate the upper THz lasing state to aid the THz-laser population inversion via optical pumping instead of direct electrical injection. A detailed analysis of electronic transport in the structure is carried out using a multi-level rate-equation model. The results show that the proposed structure offers an alternative approach to room temperature THz generation in QCLs. 相似文献
2.
Khezri Behrooz Maskanati Maryam Zohrevand Bahareh Liyaghati-Delshad Mozhdeh Soltanali Fatemeh 《Structural chemistry》2022,33(2):315-322
Structural Chemistry - This is an analysis report on the use of density functional theory (DFT) to investigate the potentials of pristine and amino acid–functionalized C4B32 borospherenes in... 相似文献
3.
Molecular Diversity - In current research, benzazepine derivative is synthesized via a new process of four-component reaction of isatin or its derivatives, α-haloketones, activated acetylenic... 相似文献
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5.
To construct a class of new multiwave interaction solutions for the (3+1)-dimensional generalized Kadomtsev-Petviashvili equation, we calculate different types of interaction solutions among solitons, periodic waves and rational waves using the direct algebraic method together with the inheritance solving skill. Moreover, a new algorithm is proposed with the aid of the simplified Hirota method, the conjugated parameters assignment and long wave limit strategies, from which multiwave interaction solutions among solitons, breathers and lump waves are generated. 相似文献
6.
Mohammad Javad TAGHIZADEH Maryam Saleh MOHAMMADNIA Masoumeh GHALKHANI Esmail SOHOULI 《高等学校化学研究》2022,38(2):546-551
Azaperone, with anti-anxiety and anti-aggressive activities used in veterinary medicine, is a member of the butyrophenone class. It is ordinarily utilized for a wide range of indications, such as sedation, obstetrics, and anesthesia. In this research, an improved synthetic route is presented for azaperone using a phase-transfer catalyst(PTC). In general, it was synthesized as a dopamine antagonist in four steps. The bis(2-chloroethyl) amine intermediate is easily obtained after the conversion of the alcohol groups into the chloride leaving group using thionyl chloride(95% yields). The alkylation of commercially available 2-amino pyridine in the presence of PTC was then carried out, giving 1-(pyridin-2-yl) piperazine with 75% yield. 1-(Pyridin-2-yl) piperazine was finally alkylated using 4-chloro-1-(4-fluorophenyl) butan-1-one to achieve azaperone with 60% yield. The butyrophenone intermediate was obtained via the Friedel-Crafts reaction of fluorobenzene with 4-chlorobutyryl chloride in the presence of AlCl3. High efficiency, gentle reaction conditions, and fast and simple procedure are the advantages of this method. Also, the electrochemical oxidation behaviour of azaperone was investigated using cyclic and differential pulse voltammetry techniques. Cyclic voltammetric studies indicated an irreversible process for azaperone electro-oxidation with a peak potential of 0.78 V in a phosphate buffer solution(pH=7.0) vs. Ag/AgCl(saturated KCl) electrode. The value of the peak current vs. the azaperone concentration was enhanced linearly in the range of 10―70 μmol/L, and the detection limit was found to be 3.33 μmol/L. 相似文献
7.
We will study all finite groups and their subgroups with at most four relative centralizers. 相似文献
8.
The First principles study on structural, electronic, Electron Field Gradient (EFG), optical and vibrational properties of tetragonal BaTiO3 have been done in the framework of Density Functional Theory (DFT). Obtained structural properties are in agreement with others, and also the electronic study shows that the tetragonal BaTiO3 has an indirect energy gap (Eg) about 1.864 eV by GGA and 2.6 eV by GGA-mbj at equilibrium state which Eg shifts toward small values by decreasing pressure. By increasing pressure to 31.479 GPa, the EFG decrease for O atom, and increase for Ba and Ti atoms that is a sign to piezoelectric property for tetragonal BaTiO3. The optical parameters were studied under pressure, such as the real and imaginary parts of the dielectric function, Loss function, reflection index, absorption coefficient, conductivity and reflection. Moreover, by applying hydrostatic pressure, the roots of the real part of the dielectric function shift toward higher energies, and the energy loss and absorption peak intensity were reduced. Finally, lattice vibration survey indicates the stability of tetragonal BaTiO3 under pressure. 相似文献
9.
Today the synthesis of silver nanoparticles is very common due to their numerous applications in various fields. Silver nanoparticles have unique properties such as: optical and catalytic properties, which, depend on the size and shape of the produced nanoparticles. So, today the production of silver nanoparticles with different shapes which have various uses in different fields such as medicine, are noted by many researchers. This article, is an attempt to present an overview of the shape-controlled synthesis of silver nanoparticles using various methods. 相似文献
10.
Esmaeili Hossein Armaghani T. Abedini A. Pop I. 《Journal of Thermal Analysis and Calorimetry》2019,135(6):3247-3257
Journal of Thermal Analysis and Calorimetry - The nanofluid is a mixture of base fluid and solid nanoparticles in nanosize. The heat transfer generated by the nanofluid is more than the base fluid... 相似文献