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1.
Let {X 1, ...,X m } and {Y 1, ...,Y n } be two samples independent of each other, but the random variables within each sample are stationary associated with one dimensional marginal distribution functionsF andG, respectively. We study the properties of the classical Wilcoxon-Mann-Whitney statistic for testing for stochastic dominance in the above set up.  相似文献   
2.
The mass attenuation coefficient (μ m) of 662 keV gamma rays have been measured in the extended media of bakelite and perspex under different collimation conditions. The increase in attenuation coefficient is seen with increase in sample thickness as well as with collimator size due to the contribution of multiple scattered photons in the uncollided beam of 662 keV gamma rays.  相似文献   
3.
A compact planar antenna sources with on-chip fabrication and high directivity in order to achieve large depth-of-field for better image resolution is the prospective demand for THz imaging application. Therefore, the small-gap photoconductive dipole antennas have been explored to fulfil such applications demand. However, there are certain modalities for improving the photoconductive dipole antenna performance which need to identify to accomplish high THz average radiated power and improved total efficiency. The unit-cell small-gap photoconductive dipole antenna radiation power enhancement methods need to optimize the design parameters with photoconductive material selection from theoretical simulation. Further, the potential improvement of coupling efficiency of THz wave with air as well as femto-second laser incident efficiency is also important parameters to enhance the radiation power of small-gap photoconductive dipole antenna. In this paper, we have presented an analytical procedure employing explicit mathematical expression leading to the physical behaviour of small-gap photoconductive dipole antenna. The effects of biased lines on the antenna performance parameters are discussed with the help of proposed equivalent circuit model. We have explored the effect of gap-size on the THz radiated power and on total radiation efficiency from the proposed photoconductive dipole antennas.  相似文献   
4.
Recently, delafossite materials have captured the interest of numerous researchers due to their unique characteristics of p-type conductivity and transparency. These materials exhibit promising potential in various applications such as photovoltaics, sensors, and transparent electronics. This paper presents a detailed account of the preparation of CuCrO2 delafossite via the solid-state reaction method. The structural properties of the sample are analyzed using XRD which confirms rhombohedral crystal structure with R-3m space group. The optical band gap was determined to be 3.39 eV through UV-visible spectroscopy. The morphology is studied using Laser Confocal scanning optical microscopy and the estimated grain size is found to be within the range of 7 µm.  相似文献   
5.
Kernel-type density and failure rate estimation for associated sequences   总被引:1,自引:0,他引:1  
Let {X n ,n1} be a strictly stationary sequence of associated random variables defined on a probability space (,B, P) with probability density functionf(x) and failure rate functionr(x) forX 1. Letf n (x) be a kerneltype estimator off(x) based onX 1,...,X n . Properties off n (x) are studied. Pointwise strong consistency and strong uniform consistency are established under a certain set of conditions. An estimatorr n (x) ofr(x) based onf n (x) andF n (x), the empirical survival function, is proposed. The estimatorr n (x) is shown to be pointwise strongly consistent as well as uniformly strongly consistent over some sets.  相似文献   
6.
Well‐defined and air‐stable PEPPSI (Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation) themed palladium bis‐N‐heterocyclic carbene complexes have been developed for the domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with a variety of terminal alkynes and C‐H bond arylation of benzothiazole with aryl iodides. The PEPPSI themed palladium complexes, 2a and 2b were synthesized in good yields from the reaction of corresponding imidazolium salts with PdCl2 and K2CO3 in pyridine. The new air‐stable palladium‐NHC complexes were characterized by NMR spectroscopy, X‐ray crystallography, elemental analysis, and mass spectroscopy studies. The PEPPSI themed palladium(II) bis‐N‐heterocyclic carbene complexes 2a and 2b exhibited excellent catalytic activities for domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with terminal alkynes yielding benzofuran derivatives. In addition, the palladium complexes, 2a and 2b successfully catalyzed the direct C‐H bond arylation of benzothiazole with aryl iodides as coupling partners in presence of CuI as co‐catalyst.  相似文献   
7.
8.
Fatty hydroxamic acid (FHA) immobilized in polyvinyl chloride (PVC) has been studied as a sensor element of an optical fibre chemical sensor for V(V). By using this instrument, V(V) in solution has been determined in the log concentration range of 0-2.5 (i.e. 1.0-300 mg/L). The detection limit was 1.0 mg/L. The relative standard deviation (R.S.D.) of the method for the reproducibility study at V(V) concentration of 200 mg/L and 300 mg/L were calculated to be 2.9% and 2.0%, respectively. Interference from foreign ions was also studied at 1:1 mole ratio of V(V):foreign ions. It was found that, Fe(III) ion interfered most in the determination of vanadium(V). Excellent agreement with ICP-AES method was achieved when the proposed method was applied towards determination of V(V).  相似文献   
9.
The ground state structures and their magnetic properties have been investigated for GenCr clusters (1≤n≤13)(1n13) using spin polarized density functional theory. The growth behavior of GenCr clusters for n≤13n13 shows preference of Cr atom to stabilize at the exohedral position. The binding energy increases with the increase in cluster size, but shows a small decrease w.r.t. pure Gen clusters. Interestingly, the magnetic moment in Cr doped Gen is found to be either 4μB4μB or 6μB6μB and shows no sign of magnetic quenching in any of the ground state structures and isomers investigated up to n  =13. It is found that the magnetic moment is mainly localized at the Cr atom along with small induced magnetic moment on surrounding Ge atoms. The results are consistent with the available theoretical results for n≤5n5.  相似文献   
10.
Coronavirus Disease-2019 (COVID-19) is a highly contagious disease caused by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). The World Health Organization (WHO) classified the disease a as global public health hazard on 11 March 2020. Currently, there are no adequate measures to combat viral infections, including COVID-19, and the medication guidelines for the management of COVID-19 are dependent on previous findings from SARS-CoV and MERS-CoV research. Natural products have achieved widespread acceptance around the world as a means of enhancing healthcare and disease prevention. Plants are a potential source of antiviral factors such as flavonoids, phenolic acids, terpenoids, and others. Some of these agents exhibit a broad spectrum of antiviral activity. This study aimed to screen herbal leads for possible inhibitors of the SARS-CoV-2 ADP Ribose Phosphatase enzyme (ARP). Guggulsterone was found to be highly stabilized within the active site of the viral ARP enzyme by molecular dynamic simulation with very little fluctuation throughout the simulation timeframe of 100 ns. Thus, guggulsterone can be further used to develop a safe and competent medication for evolving therapy against SARS-CoV-2 in post-preclinical and clinical trials.  相似文献   
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