scholarly journals Contact geometry for simple thermodynamical systems with friction

2020 ◽  
Vol 476 (2241) ◽  
pp. 20200244
Author(s):  
Alexandre Anahory Simoes ◽  
Manuel de León ◽  
Manuel Lainz Valcázar ◽  
David Martín de Diego
Keyword(s):  
Contact Structure ◽  
Evolution Equations ◽  
Gradient Methods ◽  
Important Class ◽  
Geometrical Structures ◽  
Laws Of Thermodynamics ◽  
Qualitative Dynamics ◽  
Isolated Systems ◽  
Jacobi Structure

By means of the Jacobi structure associated with a contact structure, we use the so-called evolution vector field to propose a new characterization of isolated thermodynamical systems with friction, a simple but important class of thermodynamical systems which naturally satisfy the first and second laws of thermodynamics, i.e. total energy preservation of isolated systems and non-decreasing total entropy, respectively. We completely clarify its qualitative dynamics, the underlying geometrical structures and we also show how to apply discrete gradient methods to numerically integrate the evolution equations for these systems.

Synthesis and characterization of poly(pyrrole-co-2-nitrocinnamaldehyde) (PPNC), a new copolymer for solar cells applications

2019 ◽  
Vol 28 (4) ◽  
pp. 265-272 ◽  
Author(s):  
Hamou Gherras ◽  
Ahmed Yahiaoui ◽  
Aicha Hachemaoui ◽  
Abdelkader Belfedal ◽  
Abdelkader Dehbi ◽  
...  
Keyword(s):  
Proton Nuclear Magnetic Resonance ◽  
Synthesis And Characterization ◽  
Important Class ◽  
Visible Spectroscopy ◽  
Electrical Stability ◽  
Efficient Catalyst ◽  
Heterocyclic Polymers ◽  
Conjugated Copolymer ◽  
Aromatic Heterocyclic

The use of conductive polymers as a substitute for metallic conductors and semiconductors has attracted much attention in the literature. In particular, aromatic heterocyclic polymers constitute an important class since they possess chemical and electrical stability in both the oxidized (doped) and neutral (undoped) state. A series of poly(pyrrole- co-2-nitrocinnamaldehyde) were obtained via the condensation of pyrrole and 2-nitrocinnamaldehyde in chloroform using acid exchanged montmorillonite clay called maghnite-H+ as an efficient catalyst. The conjugated copolymer was characterized using proton nuclear magnetic resonance, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy.

scholarly journals Unveiling Signatures of Topological Phases in Open Kitaev Chains and Ladders

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 894 ◽  
Author(s):  
Alfonso Maiellaro ◽  
Francesco Romeo ◽  
Carmine Antonio Perroni ◽  
Vittorio Cataudella ◽  
Roberta Citro
Keyword(s):  
Electrical Response ◽  
Differential Conductance ◽  
Model Parameters ◽  
Topological Phases ◽  
Topological Order ◽  
Topological Phase ◽  
Moderate Amount ◽  
Topological System ◽  
Isolated Systems

In this work, the general problem of the characterization of the topological phase of an open quantum system is addressed. In particular, we study the topological properties of Kitaev chains and ladders under the perturbing effect of a current flux injected into the system using an external normal lead and derived from it via a superconducting electrode. After discussing the topological phase diagram of the isolated systems, using a scattering technique within the Bogoliubov–de Gennes formulation, we analyze the differential conductance properties of these topological devices as a function of all relevant model parameters. The relevant problem of implementing local spectroscopic measurements to characterize topological systems is also addressed by studying the system electrical response as a function of the position and the distance of the normal electrode (tip). The results show how the signatures of topological order affect the electrical response of the analyzed systems, a subset of which being robust also against the effects of a moderate amount of disorder. The analysis of the internal modes of the nanodevices demonstrates that topological protection can be lost when quantum states of an initially isolated topological system are hybridized with those of the external reservoirs. The conclusions of this work could be useful in understanding the topological phases of nanowire-based mesoscopic devices.

Towards the Synthesis of Mono- and Bi-Functional Amphiphilic Oligothiophenes: Organic Materials for Opto-Electronic Applications

1999 ◽  
Vol 561 ◽  
Author(s):  
R.C. Advincula ◽  
S. Inaoka ◽  
M. Park ◽  
D. Phillips ◽  
D.M. Shin
Keyword(s):  
Physical Properties ◽  
Ultrathin Films ◽  
Organic Materials ◽  
Photophysical Properties ◽  
Electronic Devices ◽  
Synthesis And Characterization ◽  
Important Class ◽  
Maldi Tof Ms ◽  
Tof Ms

ABSTRACTIn this report, we describe our initial synthesis and characterization of mono-functional and bi-functional dibromoalkyl oligothiophenes to achieve amphiphilicity and telechelic functionality. Oligothiophenes are an important class of organic materials for opto-electronic devices and display applications. We have mono-functionalized oligothiophenes by the synthesis of a quinquethiophene bromoalkyl derivative. A bi-functional sexithiophene was derived primarily by the symmetrical coupling of terthiophene derivatives. Both were synthesized using Grignard coupling and lithiation reaction methodologies. UV-Vis, IR, NMR, MALDI-TOF-MS, and DSC confirmed the structure and physical properties of the oligomers. In addition, we have also synthesized an amphiphilic diamine derivative from the reaction of hexamethylenediamine with a bromoalkyl terthiophene derivative. Using photoluminescence, the photophysical properties of the oligomers were found to be that of typical oligothiophenes. Processing as ultrathin films for devices is currently being investigated.

scholarly journals On Some Transverse Geometrical Structures of Lifted Foliation to Its Conormal Bundle

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Cristian Ida ◽  
Alexandru Oană
Keyword(s):  
Normal Bundle ◽  
Contact Structure ◽  
Geometrical Structures ◽  
Liouville Distribution ◽  
Conormal Bundle

We consider the lift of a foliation to its conormal bundle and some transverse geometrical structures associated with this foliation are studied. We introduce a good vertical connection on the conormal bundle and, moreover, if the conormal bundle is endowed with a transversal Cartan metric, we obtain that the lifted foliation to its conormal bundle is a Riemannian one. Also, some transversally framedf(3, ε)-structures of corank 2 on the normal bundle of lifted foliation to its conormal bundle are introduced and an almost (para)contact structure on a transverse Liouville distribution is obtained.

The chemical synthesis and physical characterization of , an important class of membrane glycolipids

1990 ◽  
Vol 55 (3) ◽  
pp. 309-321 ◽  
Author(s):  
David A. Mannock ◽  
Ruthven N.A.H. Lewis ◽  
Ronald N. McElhaney
Keyword(s):  
Chemical Synthesis ◽  
Physical Characterization ◽  
Important Class

scholarly journals Characterization of Air-Based Photovoltaic Thermal Panels with Bifacial Solar Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
P. Ooshaksaraei ◽  
K. Sopian ◽  
R. Zulkifli ◽  
Saleem H. Zaidi
Keyword(s):  
Power Generation ◽  
Total Energy ◽  
Electrical Power ◽  
Exergy Efficiency ◽  
Solar Panels ◽  
First Law Of Thermodynamics ◽  
Laws Of Thermodynamics ◽  
The Cost ◽  
Single Path

Photovoltaic (PV) panels account for a majority of the cost of photovoltaic thermal (PVT) panels. Bifacial silicon solar panels are attractive for PVT panels because of their potential to enhance electrical power generation from the same silicon wafer compared with conventional monofacial solar panels. This paper examines the performance of air-based bifacial PVT panels with regard to the first and second laws of thermodynamics. Four air-based bifacial PVT panels were designed. The maximum efficiencies of 45% to 63% were observed for the double-path-parallel bifacial PVT panel based on the first law of thermodynamics. Single-path bifacial PVT panel represents the highest exergy efficiency (10%). Double-path-parallel bifacial PVT panel is the second preferred design as it generates up to 20% additional total energy compared with the single-path panel. However, the daily average exergy efficiency of a double-path-parallel panel is 0.35% lower than that of a single-path panel.

scholarly journals Generalized Mehler Semigroup on White Noise Functionals and White Noise Evolution Equations

Mathematics ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 1025
Author(s):  
Un Cig Ji ◽  
Mi Ra Lee ◽  
Peng Cheng Ma
Keyword(s):  
Evolution Equation ◽  
White Noise ◽  
Explicit Form ◽  
Infinitesimal Generator ◽  
Evolution Equations ◽  
Time Derivative ◽  
White Noise Functionals

In this paper, we study a representation of generalized Mehler semigroup in terms of Fourier–Gauss transforms on white noise functionals and then we have an explicit form of the infinitesimal generator of the generalized Mehler semigroup in terms of the conservation operator and the generalized Gross Laplacian. Then we investigate a characterization of the unitarity of the generalized Mehler semigroup. As an application, we study an evolution equation for white noise distributions with n-th time-derivative of white noise as an additive singular noise.

Existence of local stable manifolds for some nondensely defined nonautonomous partial functional differential equations

2019 ◽  
Vol 12 (08) ◽  
pp. 1950088
Author(s):  
Amor Rebey
Keyword(s):  
Evolution Equations ◽  
Linear Part ◽  
Admissible Function ◽  
Functional Differential Equations ◽  
Stable Manifolds ◽  
Functional Differential ◽  
Linear Differential ◽  
Lipschitz Conditions ◽  
Local Stable Manifolds

In this paper, we establish the existence of local stable manifolds for a semi-linear differential equation, where the linear part is a Hille–Yosida operator on a Banach space and the nonlinear forcing term [Formula: see text] satisfies the [Formula: see text]-Lipschitz conditions, where [Formula: see text] belongs to certain classes of admissible function spaces. The approach being used is the fixed point arguments and the characterization of the exponential dichotomy of evolution equations in admissible spaces of functions defined on the positive half-line.

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