Signature of the γ\gamma+jet and dijet production mediated by an excited quark with QCD next-to-leading order accuracy at the LHC

We present a detailed study of the production and decay of the excited quark at the QCD next-to-leading order (NLO) level at the Large Hadron Collider, using the narrow width approximation and helicity amplitudes method. We find that the QCD NLO corrections can tighten the constraints on the model parameters and reduce the scale dependencies of the total cross sections. We discuss the signals of the excited quark production with decay mode $q^{\ast}\rightarrow q\gamma$ and $q^{\ast}\rightarrow qg$, and present several important kinematic distributions. Moreover, we give the upper limits of the excited quark excluded mass range and the allowed parameter space for the coupling constants and the excited quark mass.Comment: 20 pages, 13 figures; version published in PR

Transition Metal Chalcogenides for the Electrocatalysis of Water

Sustainable energy technology has received enormous attention in recent years. Specifically, electrochemical water splitting is considered to be the cleanest technique for the production of promising fuels, for example, hydrogen and oxygen, where transition metal (di)chalcogenides (TMCs) as electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) have been a growing interest. In this chapter, the typical preparation methods of TMCs such as chemical vapor phase deposition (CVD) and solvothermal synthesis are introduced. Then, several TMC materials for catalyzing HER and OER are reviewed. Most importantly, this chapter also introduced some in situ approaches to realize the mechanism of electrocatalytic behavior toward HER and OER. Finally, the conclusion and futuristic prospects of TMCs in HER and OER are discussed

Threshold resummation for the production of a color sextet (antitriplet) scalar at the LHC

We investigate threshold resummation effects in the production of a color sextet (antitriplet) scalar at next-to-next-to-leading logarithmic (NNLL) order at the LHC in the frame of soft-collinear effective theory. We show the total cross section and the rapidity distribution with NLO+NNLL accuracy, and we compare them with the NLO results. Besides, we use recent dijet data at the LHC to give the constraints on the couplings between the colored scalars and quarks.Comment: 21 pages,9 figures,3 tables; Version published in EPJ

PAN/lignin/TEOS nanofibers as precursor for the production of carbon nanofibers

Carbon nanofibers (CNF) is widely applied as heat-management materials, composite reinforcement, filtration membrance, and energy storage. Polyacrylonitrile (PAN) is the main precursor for fabrication of CNF due to its brilliant properties such as high specific surface area, high aspect ratio, high mechanical strength and flexibility. However, the manufacturing prices is high. Low-cost carbon nanofibers can be fabricated from renewable materials such as lignin. It is a second most abundant raw material on earth and can be obtained easily. Tetraethyl orthosilicate (TEOS) can be added into the CNF as pore generator to generate more porous surface and catalyze the stabilization process. Porous surface is very important in providing the CNF with high electrical performance such as improved electric double-layer capacitance in supercapacitor. In this study, lignin/PAN/TEOS carbon nanofibers was lignin/PAN/TEOS carbon nanofibers were prepared by using electrospinning method followed by the heat treatment of the up to 1000°C. Electrospun nanofibers were characterized by TGA, DSC and SEM while the carbon nanofibers were characterized by using FTIR and FESEM. The TGA results show that the major degradation temperature decreased to around 270-280°C after lignin is added due to the lower thermal stability of lignin. DSC results show the addition of TEOS shifted the exothermic peaks to lower temperature due to catalytic ability of TEOS. This indicated that the stabilization process of TEOS-incorporated CNF is kinetically higher than those without TEOS. SEM images show the morphology and diameter of the sample which decreased as the lignin concentration was increased. IR spectra show peaks around 1100 cm-1 which is correspond to Si-O-C bond. This indicated the successful formation of Si-O-C/Si-O-Si structures which will influence the properties of CNF such as electrochemical performances. FESEM shows the fiber diameter decreased as TEOS amount increased and pores were successfully produced at the surface of carbon nanofibers

Some Results On Spectrum And Energy Of Graphs With Loops

Let $G_S$ be a graph with loops obtained from a graph $G$ of order $n$ and loops at $S \subseteq V(G)$. In this paper, we establish a neccesary and sufficient condition on the bipartititeness of a connected graph $G$ and the spectrum Spec($G_S$) and Spec($G_{V(G)\backslash S}$). We also prove that for every $S \subseteq V(G)$, $E(G_S) \geq E(G)$ when $G$ is bipartite. Moreover, we provide an identification of the spectrum of complete graphs $K_n$ and complete bipartite graphs $K_{m,n}$ with loops. We characterize any graphs with loops of order n whose eigenvalues are all positive or non-negative, and also any graphs with a few distinct eigenvalues. Finally, we provide some bounds related to $G_S$.Comment: 16 pages, published versio

Highly sensitive biosensor based on a microstructured photonic crystal fibre for alcohol sensing

This research article was published by Elsevier 2023A microstructure alcohol biosensor has been proposed to operate in the wavelength range of 0.8 to 2.0 μm for the sensing of propanol, butanol, and pentanol, unveiling impressive results of relative sensitivity and confinement loss. The results are achieved by implementing closely arranged cladding air holes of 3 rings with a single elliptical core hole for analyte infiltration. Performance evaluation of the sensor was conducted using COMSOL Multiphysics software and yields relative sensitivity of 96.75%, 89.60%, and 82.02% for propanol, butanol, and pentanol, respectively, and confinement losses of 5.49 × 10 12 dB/m for propanol, 1.98 × 10 12 dB/m for butanol, and 9.36 × 10 13 dB/m for pentanol. Other optical parameters have also been analysed that recorded effective refractive index, high power fraction, low birefringence, small effective area, and large nonlinear co- efficients. The proposed biosensor is eligible for practical application in alcohol sensing with these results. Moreover, this proposed biosensor is suitable as a supercontinuum source in optical communication systems because of the high nonlinear coefficients

Interference-Aware Deployment for Maximizing User Satisfaction in Multi-UAV Wireless Networks

In this letter, we study the deployment of Unmanned Aerial Vehicle mounted Base Stations (UAV-BSs) in multi-UAV cellular networks. We model the multi-UAV deployment problem as a user satisfaction maximization problem, that is, maximizing the proportion of served ground users (GUs) that meet a given minimum data rate requirement. We propose an interference-aware deployment (IAD) algorithm for serving arbitrarily distributed outdoor GUs. The proposed algorithm can alleviate the problem of overlapping coverage between adjacent UAV-BSs to minimize inter-cell interference. Therefore, reducing co-channel interference between UAV-BSs will improve user satisfaction and ensure that most GUs can achieve the minimum data rate requirement. Simulation results show that our proposed IAD outperforms comparative methods by more than 10% in user satisfaction in high-density environments.Comment: 5 pages, 3 figures, to appear in IEEE Wireless Communications Letter

Carbon-Based Nanocomposite Materials for High-Performance Supercapacitors

Lightweight, flexible, wearable, and portable electronic gadgets have drawn significant attention in modern electronics industry. To power these gadgets, great efforts have been made to develop highly efficient energy-storage equipment. Among various power sources, a supercapacitor, acting as a bridge between the conventional battery and electrolytic capacitor, has been considered a promising portable energy storage device because of its high power density, fast charge/discharge rate, adequate operational safety, and excellent working lifetime. Hybrid supercapacitors, which combine redox materials with carbon-based materials, exhibit tremendous potential to fulfill the requirement of practical applications. In this chapter, we will review recent reports focusing on composite materials (i.e. metal oxide, metal hydroxide, and metal dichalcogenide composited with carbon materials) for the application in supercapacitors. The conclusion and futuristic prospects and challenges of highly efficient supercapacitors are briefly discussed