Probing long-range correlations in the Berezinskii-Kosterlitz-Thouless fluctuation regime of ultra-thin NbN superconducting films using transport noise measurements

We probe the presence of long-range correlations in phase fluctuations by analyzing the higher-order spectrum of resistance fluctuations in ultra-thin NbN superconducting films. The non-Gaussian component of resistance fluctuations is found to be sensitive to film thickness close to the transition, which allows us to distinguish between mean field and Berezinskii-Kosterlitz-Thouless (BKT) type superconducting transitions. The extent of non-Gaussianity was found to be bounded by the BKT and mean field transition temperatures and depend strongly on the roughness and structural inhomogeneity of the superconducting films. Our experiment outlines a novel fluctuation-based kinetic probe in detecting the nature of superconductivity in disordered low-dimensional materials.Comment: submitted to PR

Dynamic Optimization and Optimal Control of Hydrogen Blending Operations in Natural Gas Networks

We present a dynamic model for the optimal control problem (OCP) of hydrogen blending into natural gas pipeline networks subject to inequality constraints. The dynamic model is derived using the first principles partial differential equations (PDEs) for the transport of heterogeneous gas mixtures through long distance pipes. Hydrogen concentration is tracked together with the pressure and mass flow dynamics within the pipelines, as well as mixing and compatibility conditions at nodes, actuation by compressors, and injection of hydrogen or natural gas into the system or withdrawal of the mixture from the network. We implement a lumped parameter approximation to reduce the full PDE model to a differential algebraic equation (DAE) system that can be easily discretized and solved using nonlinear optimization or programming (NLP) solvers. We examine a temporal discretization that is advantageous for time-periodic boundary conditions, parameters, and inequality constraint bound values. The method is applied to solve case studies for a single pipe and a multi-pipe network with time-varying parameters in order to explore how mixing of heterogeneous gases affects pipeline transient optimization

Transitions from Monotonicity to Chaos in Gas Mixture Dynamics in Pipeline Networks

The blending of hydrogen generated using clean energy into natural gas pipeline networks is proposed in order to utilize existing energy systems for their planned lifetime while reducing their reliance on fossil fuels. We formulate a system of partial differential equations (PDEs) that govern the flow dynamics of mixtures of gases in pipeline networks under the influence of time-varying compressor and regulator control actions. The formulation is derived for general gas networks that can inject or withdraw arbitrary time-varying mixtures of gases into or from the network at arbitrarily specified nodes. The PDE formulation is discretized in space to form a nonlinear control system which is used to prove that homogeneous mixtures are well-behaved and heterogeneous mixtures may be ill-behaved in the sense of monotone-ordering of solutions. We use numerical simulations to compute interfaces that delimit periodic and monotone system responses and show that any solution in the monotonic operating region eventually approaches a periodic orbit. Our results are demonstrated for examples of a single pipeline and a small test network

The future design direction of smart clothing development

Literature indicates that Smart Clothing applications, the next generation of clothing and electronic products, have been struggling to enter the mass market because the consumers’ latent needs have not been recognised. Moreover, the design direction of Smart Clothes remains unclear and unfocused. Nevertheless, a clear design direction is necessary for all product development. Therefore, this research aims to identify the design directions of the emerging Smart Clothes industry by conducting a questionnaire survey and focus groups with its major design contributors. The results reveal that the current strategy of embedding a wide range of electronic functions in a garment is not suitable. This is primarily because it does not match the users’ requirements, purchasing criteria and lifestyle. The results highlight the respondents’ preference for personal healthcare and sportswear applications that suit their lifestyle, are aesthetically attractive, and provide a practical function

A child having rare Hereditary Multiple Exostosis with Covid-19 disease: A case study

Abstract: Hereditary Multiple Exostosis is a rare bone disease in pediatric age group. It is an autosomal dominant disorder, characterized by excessive bony overgrowth arising from lateral aspect of metaphysis of long bone, covered by a cartilaginous cap. These lesions remain asymptomatic clinically. When symptomatic, a variety of health hazards can arise like chronic pain, skeletal deformity, neuro-vascular compression etc. Malignant transformation is a rare, but feared complication. Diagnosis can be made by simple radiographic examination, when symptoms arise. Treatment is only conservative or surgical. SARS- CoV-2 may infect children with any pre-existing disease, like HME in the same proportion of healthy children. We report a rare case of hereditary multiple exostosis, simultaneously suffering from covid-19 disease, that has not been reported previously

Double Carbon−Hydrogen Activation of 2-Vinylpyridine: Synthesis of Tri- and Pentanuclear Clusters Containing the μ-NC\u3csub\u3e5\u3c/sub\u3eH\u3csub\u3e4\u3c/sub\u3eCH═C Ligand

Reactions of 2-vinylpyridine with the triruthenium complexes [Ru3(CO)12] and [Ru3(CO)10(μ-dppm)] leads to a previously unknown double carbon−hydrogen bond activation of the β-carbon of the vinyl group to afford the pentaruthenium and triruthenium complexes [Ru5(CO)14(μ4-C5H4CH═C)(μ-H)2] (1) and [Ru3Cl(CO)5(μ-CO)(μ-dppm)(μ3-NC5H4CH═C)(μ-H)] (2), respectively. Crystal structures reveal two different forms of bridging of the dimetalated 2-vinylpyridyl ligand, capping a square face in 1 and a triangular face in 2

Effect of the C-bridge length on the ultraviolet-resistance of oxycarbosilane low-k films

The ultra-violet (UV) and vacuum ultra-violet (VUV) resistance of bridging alkylene groups in organosilica films has been investigated. Similar to the Si-CH3 (methyl) bonds, the Si-CH2-Si (methylene) bonds are not affected by 5.6 eV irradiation. On the other hand, the concentration of the Si-CH2-CH2-Si (ethylene) groups decreases during such UV exposure. More significant difference in alkylene reduction is observed when the films are exposed to VUV (7.2 eV). The ethylene groups are depleted by more than 75% while only about 40% methylene and methyl groups loss is observed. The different sensitivity of bridging groups to VUV light should be taken into account during the development of curing and plasma etch processes of low-k materials based on periodic mesoporous organosilicas and oxycarbosilanes. The experimental results are qualitatively supported by ab-initio quantum-chemical calculations

Bengali women's ideas about water quality

Respecting cultural beliefs and customary practices is part of the rights- and commons-based thinking about water. The focus is on place-based practices and beliefs. Incorporating indigenous beliefs into any new, participatory approach to water management, however, is quite challenging to the scientifically oriented development professional. This paper explains to the basics of cultural views of water among Bengali-speaking people of the southern, eastern, and western parts of the Bangladesh delta. Examples are drawn from the authors’ work on arsenic in drinking water and other WASH issues. Ideas such as hot/cold or pure/impure are perceived as “superstitions” by many scientists. If our thinking about water life is to change in the direction the commons-based approach suggests -- to incorporate indigenous views into place-based planning – the main obstacle will be with those who now have the upper hand, not those who are marginalized. Planning processes should be organized in ways that respect local views and take them into consideration when introducing new technologies

Stochastic Finite Volume Method for Uncertainty Management in Gas Pipeline Network Flows

Natural gas consumption by users of pipeline networks is subject to increasing uncertainty that originates from the intermittent nature of electric power loads serviced by gas-fired generators. To enable computationally efficient optimization of gas network flows subject to uncertainty, we develop a finite volume representation of stochastic solutions of hyperbolic partial differential equation (PDE) systems on graph-connected domains with nodal coupling and boundary conditions. The representation is used to express the physical constraints in stochastic optimization problems for gas flow allocation subject to uncertain parameters. The method is based on the stochastic finite volume approach that was recently developed for uncertainty quantification in transient flows represented by hyperbolic PDEs on graphs. In this study, we develop optimization formulations for steady-state gas flow over actuated transport networks subject to probabilistic constraints. In addition to the distributions for the physical solutions, we examine the dual variables that are produced by way of the optimization, and interpret them as price distributions that quantify the financial volatility that arises through demand uncertainty modeled in an optimization-driven gas market mechanism. We demonstrate the computation and distributional analysis using a single-pipe example and a small test network

Explicit finite difference analysis of an unsteady magnetohydrodynamics heat and mass transfer micropolar fluid flow in the presence of radiation and chemical reaction through a vertical porous plate

The investigation of this paper is undertaken to study of the problem of chemical reaction on MHD unsteady heat and mass transfer effects of micropolar fluid flow through a vertical plate. Different effects such as thermal diffusion, Soret and Dufour effects in the presence of radiation and chemical reaction are permitted in this observation. Firstly, the governing partial differential equations (PDEs) are transformed into a system of dimensionless coupled partial differential equations by the procedure of mathematical transformation. Then the obtained dimensionless equations are solved by explicit finite difference method (EFDM). Further, the momentum, temperature and concentration distributions are permitted by the variations of various parameters with the help of computer programming language FORTRAN. By using initial boundary conditions U = 0, V = 0, Γ = 0, T = 1, C = 1 and for Δτ = 0.0005, ΔX = 0.83 and ΔY = 0.50, the convergence criteria are exhibited Pr ≥ 0.205 and Sc ≥ 0.045. In addition, the streamlines and isotherms are evaluated for different interesting parameters. Finally, after stability convergence test (SCT) the profiles of velocity, angular velocity, temperature and concentration are analysed and scrutinized graphically by using graphs software tacplot-9