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111.
Jani D. B. Bhabhor Kiran Dadi Mohsin Doshi Sachindra Jotaniya P. V. Ravat Harish Bhatt Kumar 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2011-2031
Journal of Thermal Analysis and Calorimetry - Solid desiccant-assisted cooling and dehumidification systems are becoming very popular nowadays for maintaining the required thermal comfort in... 相似文献
112.
Combined parametric optimization of P3HT: PC70BM films for efficient bulk-heterojunction solar cells
Siddiqui Hafsa Parra Mohammad Ramzan Pandey Padmini Qureshi M. S. Haque Fozia Zia 《Journal of Solid State Electrochemistry》2019,23(12):3267-3274
Journal of Solid State Electrochemistry - In this report, the effects of photoactive blend compositions, film thicknesses, and annealing conditions on the P3HT:PC70BM solar cells performance and... 相似文献
113.
Emergence of classicality from quantum mechanics, a hotly debated topic, has had no satisfactory resolution so far. Various approaches including decoherence and gravitational interactions have been suggested. In the present work, the Schrödinger–Newton model is used to study the role of semi-classical self-gravity in the evolution of massive spin-1/2 particles in a Stern-Gerlach experiment. For small mass, evolution of the initial wavepacket in a spin superposition shows a splitting in the magnetic field gradient into two trajectories as in the standard Stern–Gerlach experiment. For larger mass, the deviations from the central path are less than in the standard Stern–Gerlach case, while for high enough mass, the wavepacket does not split, and instead follows the classical trajectory for a magnetic moment in inhomogeneous magnetic field. This indicates the emergence of classicality due to self-gravitational interaction when the mass is increased. In contrast, decoherence which is a strong contender for emergence of classicality, leads to a mixed state of two trajectories corresponding to the spin-up and spin-down states, and not the classically expected path. The classically expected path of the particle probably cannot be explained even in the many-worlds interpretation of quantum mechanics. Stern–Gerlach experiments in the macroscopic domain are needed to settle this question. 相似文献
114.
We introduce balanced polyominoes and show that their ideal of inner minors is a prime ideal and has a squarefree Gröbner basis with respect to any monomial order, and we show that any row or column convex and any tree‐like polyomino is simple and balanced. 相似文献
115.
Static and dynamical magnetic properties of Fe nanoparticles (NPs) embedded in non-magnetic (Ag) and antiferromagnetic (Cr) matrices with a volume filling fraction (VFF) of 10% have been investigated. In both Fe@Ag and Fe@Cr nanocomposites, the Fe NPs have a narrow size distribution, with a mean particle diameter around 2 nm. In both samples, the saturation magnetization reaches that of Fe bulk bcc, suggesting the absence of alloying with the matrices. The coercivity at 5 K is much larger in Fe@Cr than in Fe@Ag as a result of the strong interaction between the Fe NPs and the Cr matrix. Temperature-dependent magnetization and ac-susceptibility measurements point out further evidence of the enhanced interparticle interaction in the Fe@Cr system. While the behaviour of Fe@Ag indicates the presence of weakly interacting magnetic monodomain particles with a wide distribution of blocking temperatures, Fe@Cr behaves like a superspin glass produced by the magnetic interactions between NPs. 相似文献
116.
Afzal Shah Muhammad Zaheer Rumana Qureshi Zareen Akhter Muhammad Faizan Nazar 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1082-1087
Cyclic voltammetry (CV) coupled with UV–vis and fluorescence spectroscopy were used to probe the interaction of potential anticancer drug, 4-nitrophenylferrocene (NFC) with DNA. The electrostatic interaction of the positively charged NFC with the anionic phosphate of DNA was evidenced by the findings like negative formal potential shift in CV, ionic strength effect, smaller bathochromic shift in UV–vis spectroscopy, incomplete quenching in the emission spectra and decrease in viscosity. The diffusion coefficients of the free and DNA bound forms of the drug were evaluated from Randles–Sevcik equation. The binding parameters like binding constant, ratio of binding constants (Kred/Kox), binding site size and binding free energy were determined from voltammetric data. The binding constant was also determined from UV–vis and fluorescence spectroscopy with a value quite close to that obtained from CV. 相似文献
117.
Afzal Shah Victor C. Diculescu Niaz Muhammad Rumana Qureshi Saqib Ali Ana Maria Oliveira‐Brett 《Electroanalysis》2010,22(1):121-127
The electrochemical behavior of Na‐salt of 2‐methyl‐3‐(4‐nitrophenyl)acrylate (NPA) and its reduction product was studied by cyclic (CV), differential pulse(DPV) and square wave voltammetry (SWV) using a glassy carbon electrode (GCE). The results revealed that NPA is irreversibly reduced leading to the formation of a reduction product (PNPA). For pH<9.0 the peak potential was linearly dependent on pH. For pH>9.0 the peak potential was pH‐independent and the value of pKb≈9.0 was determined. The adsorbed PNPA exhibited reversible redox reaction. The reduction of PNPA was pH dependent. To ensure that the electrochemical behavior of NPA is due to the reducible moiety, NO2, closely related compounds to NPA were also studied, and a redox mechanism was proposed for NPA. 相似文献
118.
A three-residue trans-cyclopropane gamma-peptide adopts an infinite parallel sheet structure in the solid state stabilized by intermolecular C-H...O hydrogen bonds, as demonstrated by single crystal X-ray diffraction. 相似文献
119.
I. E. Qureshi M. I. Shahzad M. A. Farooq A. H. Dogar S. Manzoor M. A. Rana H. A. Khan 《Radiation measurements》2001,34(1-6):249-254
It has been demonstrated that high-energy heavy ions undergo fission while propagating in dielectric solids. Since these materials act as particle detectors because of their ability to retain primary ionization damage that can be fixed and enlarged with chemical etching, therefore, in principle, a complete kinematical analysis of fission events is possible. The crucial point in this regard is the availability of a well-calibrated range-energy relation, which is necessary for mass identification. We have developed an analytical method to convert the geometrical parameters of fission fragment tracks into physical parameters using an equation that expresses velocity as a polynomial of mass and range. A set of nine different polynomials was used to represent small regions of mass and range in order to improve accuracy. In the case of (15.9 MeV/u) Au ions incident normally on CR-39, we have found about 200 events which could be categorized as in-flight fission of Au ions inside the body of the detector. Mass distributions and cross sections of fission events have been calculated. 相似文献
120.
Lajna P. Vijayan Bhakti V. Raigaonkar M.S. Qureshi R.N. Dubey M.M. Malik 《Journal of Electrostatics》2010,68(4):384-389
This paper reports the study of surface charge characteristics of bio-magnetoelectrets of amino acid l-serine. Electrets were prepared under the combined effect of heat and magnetic field. Three different forming temperatures and five different magnetic fields were used for the study. The bio-magnetoelectrets prepared this way were observed to have a surface charge of the order of 10?9 C. The decay of surface charge was studied continuously for 20 days and corresponding time constant was calculated. The comparative studies of surface charge characteristics were done by preparing bio-magnetoelectrets using homogeneous and inhomogeneous magnetic fields. 相似文献