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41.
We present an algebra generated by a single pair of creation and annihilation operators b and b*. We prove that the algebra has a unique d-dimensional representation. Physically this algebra corresponds to a system where there are at most d − 1 particles in a state with otherwise same quantum numbers. 相似文献
42.
Ibrahim Tekin Yashar T. Mehraliyev Mansur I. Ismailov 《Mathematical Methods in the Applied Sciences》2019,42(10):3739-3753
In this paper, an initial boundary value problem for nonlinear Klein‐Gordon equation is considered. Giving an additional condition, a time‐dependent coefficient multiplying nonlinear term is determined, and existence and uniqueness theorem for small times is proved. The finite difference method is proposed for solving the inverse problem. 相似文献
43.
Controlling the electrical characteristics of Au/n‐Si structure with and without (biphenyl‐CoPc) and (OHSubs‐ZnPc) interfacial layers at room temperature 下载免费PDF全文
Nalan Baraz İbrahim Yücedağ Ahmet Demir Gülçin Ersöz Şemsettin Altındal Mehmet Kandaz 《先进技术聚合物》2017,28(8):952-957
In order to interpret well whether or not the organic or polymer interfacial layer is effective on performance of the conventional Au/n‐Si (metal semiconductor [MS]) type Schottky barrier diodes (SBDs), in respect to ideality factor (n ), leakage current, rectifying rate (RR ), series and shunt resistances (Rs , Rsh ) and surface states (Nss ) at room temperature, both Au/biphenyl‐CoPc/n‐Si (MPS1) and Au/OHSubs‐ZnPc/n‐Si (MPS2) type SBDs were fabricated. The electrical characteristics of these devices have been investigated and compared by using forward and reverse bias current–voltage (I–V ) characteristics in the voltage range of (?4 V)–(4 V) for with and without (biphenyl‐CoPc) and (OHSubs‐ZnPc) interfacial layers at room temperature. The main electrical parameters of these diodes such as reverse saturation current (I0 ), ideality factor (n ), zero‐bias barrier height (ΦB0 ), RR , Rs and Rsh were found as 1.14 × 10?5 A, 5.8, 0.6 eV, 362, 44 Ω and 15.9 kΩ for reference sample (MS), 7.05 × 10?10 A, 3.8, 0.84 eV, 2360, 115 Ω and 270 kΩ for MPS1 and 2.16 × 10?7 A, 4.8, 0.7 eV, 3903, 62 Ω and 242 kΩ for MPS2, respectively. It is clear that all of these parameters considerably change by using an organic interfacial layer. The energy density distribution profile of Nss was found for each sample by taking into account the voltage dependence of effective barrier height (Φe ) and ideality factor, and they were compared. Experimental results confirmed that the use of biphenyl‐CoPc and OHSubs‐ZnPc interfacial layer has led to an important increase in the performance of the conventional of MS type SBD. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
44.
Nalan iek Bezir Atilla Evcin Refik Kayal Murivet Kakc
zen Aye Oktay 《Crystal Research and Technology》2016,51(1):65-73
Pure and 1, 2, and 3 wt% Ag doped TiO2 nanofibers were prepared by electrospinning method at different applied voltages and heights at a constant flow rate of 2 mL/h. Characterization of the prepared samples was performed by x‐ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microcopy (AFM),four point probe method (FPPM), the differential scanning calorimetry/the thermal gravimetric analysis (DSC/TGA), ultraviolet/visible spectrometry (UV/VIS), and energy dispersive X‐ray spectrometer (EDX). It was found that the thermally untreated pure TiO2 nanofibers and thermally treated (at 500 °C) samples have the crystalline phase of anatase (A), and mixed anatase and rutile (A+R) phases, respectively. It was also observed that the content of the silver does not affect the crystal structure, but plays strengthening role in the rutile structure. SEM micrographs showed that all fabricated nanofiber samples have uniform morphologies, and AFM measurements indicated that the nanofibers were formed in three‐dimensional coils. The band gap values of the nanofiber samples obtained from UV/VIS measurements revealed that band gap values of the nanofiber samples decrease while the diameter of the nanofiber increases. 相似文献
45.
The notion of self-duality of 2-forms in 4-dimensions plays an eminent role in many areas of mathematics and physics, but although the 2-forms have a genuine meaning related to curvature and gauge-field-strength in higher dimensions also, their “self-duality” is something which is almost avoided above 4-dimensions. We show that self-duality of 2-forms is a very natural notion in higher (even) dimensions also and we prove the equivalence of some scattered and rarely used definitions in the literature. We demonstrate the usefulness of this higher self-duality by studying it in 8-dimensions and we derive a natural expression for the Bonan form in terms of self-dual 2-forms and we give an explicit expression of the local action of SO(8) on the Bonan form. 相似文献
46.
We report the definition and refinement of a new first principles potential for the acetylene dimer. The ab initio calculations were performed with the DFT-SAPT combination of symmetry-adapted intermolecular perturbation method and density functional theory, and fitted to a model site-site functional form. Comparison of the calculated microwave spectrum with experimental data revealed that the barriers to isomerization were too low. This potential was refined by fitting the model parameters in order to reproduce the observed transitions, an excellent agreement within ~1 MHz being achieved. 相似文献
47.
Özlem Selçuk Zorer Tekin Şahan 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):417-421
Gross α and gross β activities and 238U concentrations were determined in 18 surface water samples collected from Van Lake. The instrumentations used to count the
gross α and gross β activities and to determine the 238U concentrations were α/β counter of the multi-detector low background system (PIC-MPC-9604) and Inductively Coupled Plasma-Mass
Spectrometry (Thermo Scientific Element 2), respectively. Concentrations ranging from 0.001 to 0.021 Bq L−1 and from 0.111 to 2.794 Bq L−1 were observed for the gross α and β activities in surface waters, respectively. For all samples the gross β activities were
higher than the corresponding gross α activities. The results indicated that the gross α radioactive contamination in water
samples was lower than recommended values for the guideline of drinking waters and most of the gross β activities in water
samples were higher than those in the same procedure. The 238U concentrations ranged from 74.49 to 113.2 μg L−1 in surface waters. The obtained results have showed that 238U concentrations are higher than guideline values for uranium. 相似文献
48.
Strength and ultrasonic properties of cemented paste backfill 总被引:1,自引:0,他引:1
This paper presents the strength (UCS) and ultrasonic pulse velocity (UPV) properties of cemented paste backfill (CPB) produced from two different mill tailings (Tailings T1 and T2). A total of 240 CPB samples with diameter × height of 5 × 10 cm and 10 × 20 cm prepared at different binder dosages (5–7 wt.%) and water-to-cement ratios (3.97–5.10) were subjected to the UPV and UCS tests at 7, 14, 28 and 56-days of curing periods. UCS and UPV of CPB samples increased with increasing the binder dosage and reducing the w/c ratio irrespective of the sample size and tailings type. CPB samples with a diameter × height of 5 × 10 cm were observed to produce consistently higher (up to 1.69-fold) UCSs than those of 10 × 20 cm CPB samples at all binder dosages and w/c ratios. However, at the corresponding binder dosages and w/c ratios, the maximum variation of UPV between the CPB samples of 5 × 10 cm and 10 × 20 cm was only 7.45%. Using the method of least squares regression, the UCS values were correlated with the UPV values for CPB samples of 10 × 20 cm in size. A linear relation with a high correlation coefficient appeared to exist between the UCS and UPV for CPB samples. These findings suggest that the UPV is essentially independent of the sample size. In this regard, the UPV test can be suitably exploited for the rapid estimation of the strength and quality of CPB samples even using small samples with concomitant benefits of reducing sample size. 相似文献
49.
Muharrem Diner Namk
zdemir Ahmet etin Tekin Keser Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o639-o642
In the title compound, C22H25N5OS·2H2O, the molecules are stacked in columns running along the b axis. In this arrangemant, the molecules are linked to each other by a combination of one two‐centre N—H⋯O hydrogen bond and four two‐centre O—H⋯O hydrogen bonds containing two types of ring motif, viz.R44(10) and R33(11). In the crystal structure, centrosymmetric π–π interactions between the triazole rings, with a distance of 3.691 (2) Å between the ring centroids, also affect the packing of the molecules. 相似文献
50.
Zeynep Gönül Dilara Altay Öztürk Fatümetüzzehra Küçükbay Suat Tekin Zehra Tekin Hasan Küçükbay 《Journal of heterocyclic chemistry》2023,60(1):86-95
In this study, 10 new indole-dipeptide conjugates were synthesized, and their anticancer activity was determined against on A2780 (ovarian cancer cell line) and MCF-7 (breast cancer cell line) cells. Among compounds, 5 and 10 showed better activity against A2780 cell lines than the standard drug docatexel at 0.1 and 1 μM concentrations, while only compound 5 showed better activity than docatexel, the MCF-7 cell line at 0.1 and 1 μM concentrations. The antioxidant potencies of the compounds were low in both the DPPH and iron reducing power methods tested when compared to standard antioxidants used in this work. 相似文献