Top PDF A Simplified Approach to the Problems of Room Temperature Superconductivity

A Simplified Approach to the Problems of Room Temperature Superconductivity

A Simplified Approach to the Problems of Room Temperature Superconductivity

superconductivity is two-dimensional in them. “Pseudogap” state and a diagram showing the dependence of the quantum state of the degree of doping are strange. Pseudogap state is subjected to complex researches, but a simple model still does not exist. A theory in which the superconducting and charge-density wave orders exhibit angular fluctuations in a six-dimensional space is presented in [1]. This theory provides a natural quantitative fit to the experimental data but cannot give us understanding of the pseudogap nature. This example shows the com- plexity of the features of HTSC, so survey in one article is impossible. Our goal is another to find a simplified micro-approach. From this point of view, it is interesting to note the detection of topological insulator (TI) state in HTSC and term “topological superconductivity” [2].
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A Different Approach to High Tc Superconductivity: Indication of Filamentary Chaotic Conductance and Possible Routes to Room Temperature Superconductivity

A Different Approach to High Tc Superconductivity: Indication of Filamentary Chaotic Conductance and Possible Routes to Room Temperature Superconductivity

The composition for such composites will be passed 4 by the empirical relation of Tco = 2740 q c that connects the transition temperature Tco of optimum doped superconductors with the me[r]

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Simplified models for heating system optimisation using a thermal electrical analogy

Simplified models for heating system optimisation using a thermal electrical analogy

For the data under consideration here, the supply tempera- tures are reduced during the working day in order to maintain the room set points, as illustrated by Fig. 2. The supply temperatures are constant during the weekend. This pattern is repeated during the first 25 days of the month, during which time the rooms are generally warmer than the supply and ambient temperatures. By contrast, the right hand side of Fig. 2 shows that the supply temperatures are significantly higher during the last few days of September, although there is no obvious change in the outside temperature profile to explain this. For the model optimisation example considered later, the first two weeks of September 2017 are used for estimation purposes and the final two weeks for validation. This approach ignores the changing dynamics noted above and clearly requires more research. Finally, it is clear that room two is consistently a little colder than room one, and suffers greater variation in temperature, which is likely to be due to its position next to the atrium, with the associated heat losses.
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Superconductivity in ropes of carbon nanotubes

Superconductivity in ropes of carbon nanotubes

Recent experimental and theoretical results on intrinsic superconductivity in ropes of single- wall carbon nanotubes are reviewed and compared. We find strong experimental evidence for superconductivity when the distance between the normal electrodes is large enough. This indi- cates the presence of attractive phonon-mediated interactions in carbon nanotubes, which can even overcome the repulsive Coulomb interactions. The effective low-energy theory of rope super- conductivity explains the experimental results on the temperature-dependent resistance below the transition temperature in terms of quantum phase slips. Quantitative agreement with only one fit parameter can be obtained. Nanotube ropes thus represent superconductors in an extreme 1D limit never explored before.
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Customised ocular prosthesis  A simplified approach

Customised ocular prosthesis A simplified approach

The disfigurement after the loss of an eye can cause significant physical and psychological disturbance to a patient. The rehabilitation of an ocular defect patient is a challenging task both clinically and technically. A Custom made ocular prosthesis aids in replicating the exact location of the iris and gaze of the patient along with an accurate reproduction of the color, contour, and size of bes a simplified approach for fabricating an accurate, made ocular prosthesis in an attempt to restore facial symmetry and

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Are silanes the primary driver of interface strength in glass fibre composites? : exploring the relationship of the chemical and physical parameters which control composite interfacial strength

Are silanes the primary driver of interface strength in glass fibre composites? : exploring the relationship of the chemical and physical parameters which control composite interfacial strength

reveal some similarity with a maximum value occurring around R=1 and both IFSS and Tg reducing as R moves away from unity (in either direction). A particularly interesting correlation is the position of the large step down in IFSS when R<0.5. It is also at this approximate value of R that the matrix Tg drops below room temperature. Consequently, the very low values of IFSS observed for R<0.5 in Figure 3 were measured at a temperature above the matrix Tg when presumably there is little remaining residual interfacial stress to contribute to the measured IFSS. This appears to be the same phenomenon observed in Figure 2b where the experiment design involved a fixed matrix Tg (≈80 °C for R=1) and measurement of IFSS at temperatures above and below this value. In Figure 3 the experiment is designed with a constant IFSS measurement temperature but a changing epoxy matrix Tg. In both cases a similar effect can be observed of reduced IFSS when the measurement temperature is above the Tg of the matrix polymer. Further work to characterise the system IFSS as a function of both R value and temperature is planned [4,27].
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Efficient Route for the Synthesis of New Derivatives of Bioactive Organic Compounds at Room Temperature

Efficient Route for the Synthesis of New Derivatives of Bioactive Organic Compounds at Room Temperature

Ruthenium-catalyzed double addition of indoles to aldehydes. A mixture of indole (2 mmol), aldehyde (1 mmol) and RuCl 3 .nH 2 O (1.2mol%, 0.012 mmol) was stirred at room temperature for the appropriate time (see Table 1). After completion of the reaction as was monitored by TLC, the precipitated product was filtrated and rinsed with cold reaction solvent. In the case of entry 8 in Table 1, purification of the reaction mixture by preparative TLC (petroleum ether-ethyl acetate, 10:3) provided the pure product.

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Correlated Electron Systems and High Temperature Superconductivity

Correlated Electron Systems and High Temperature Superconductivity

We have investigated the superconductivity of electronic origin on the basis of the (single-band and three-band) two-dimensional Hubbard model. First, we employ the variational Monte Carlo method to clarify the phase diagram of the ground state of the Hubbard model. The superconducting condensation energy per site obtained by the Gutzwiller ansatz is reasonably close to experimental value 0.17  0.26 meV site . We have examined the stability of striped and checkerboard states in the under-doped region. The relation of the incom- mensurability and hole density,   x , is satisfied in the
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A Simplified Model of the Dynamic Response of a Finned-tube Heat Exchanger

A Simplified Model of the Dynamic Response of a Finned-tube Heat Exchanger

Pri analizi dinam ičnega odziva prenosnika toplote smo želeli pridobiti tudi informacije o dogajanjih znotraj obravnavanega sistema, zato smo za reševanje matematičnega modela uporabili numerične metode. Namen analize z numeričnim modeliranjem je bil tudi ugotoviti, do kakšne stopnje lahko poenostavimo m atem atični m odel, da bom o dobili še ustrezne rezultate pri sim uliranju dinam ičnega delovanja prenosnika toplote. V našem primeru smo za analizo izbrali standardni lamelni prenosnik, z vodo kot delovnim medijem za hlajenje oziroma gretje vlažnega zraka. Njegovo delovanje smo analizirali glede na spremembe izstopne temperature zraka v odvisnosti od spremembe vstopne temperature vode v področju občutnega hlajenja vlažnega zraka.
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DIMZAL: A Software Tool to Compute Acceptable Safety Distance

DIMZAL: A Software Tool to Compute Acceptable Safety Distance

This paper presents a multidisciplinary work and argues a software tool (DIMZAL) to compute Acceptable Safety Distance (ASD). This distance was usually set thanks to a general rule-of-thumb: it should be at least 4 times the maximum flame length. This distance is very important because it is used to design fuel breaks. In the proposed ap- proach, to quantify this ASD, a closed physical model is used, including a physical propagation model, a flame length submodel and an analytical model for the computa- tion of ASD. The model is hosted as a web service, and used a simulation framework based on Discrete EVent system Specification formalism (DEVS). In this new work, various results based on the vegetation characterization are presented. Model predic- tions are compared against measured flame length of spreading fires through shrub ve- getation. This work shows that the simplified physical approach presents a main ad- vantage: its capability to be used for all types of fires under a wide range of conditions if fuel models, describing structural types of vegetation, are available. So, this tool can be seen as an alternative operational length flame model, which can be applied to calculate more accurately safety distances and to forecast fuelbreak safety zone sizes at the field scale.
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The importance of a multidisciplinary approach to hepatocellular carcinoma

The importance of a multidisciplinary approach to hepatocellular carcinoma

The complexity of these scoring and staging systems calls for interaction of various specialties at different stages of the disease. Gastroesophageal varices, ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, and hepatic encephalopathy often coincide with treatment of HCC, both during curative therapy and palliative care. Early recognition and treatment of each of these concurrent complications are vital for improving outcomes. Published literature have also backed the idea that an integrated multidisciplinary approach can help optimize the management of HCC patients. 5,10 Pub-
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Heat Losses to the Ground According to the SIST EN ISO 13370 Standard – a Simplified Calculation Method

Heat Losses to the Ground According to the SIST EN ISO 13370 Standard – a Simplified Calculation Method

za dani primer znotraj obmoèja -8% do +12%. Pri vseh preostalih analiziranih primerih pa je prièakovana nenatanènost med metodo po SIST EN ISO 13370 in razvito poenostavljeno metodo znotraj obmoèja, ki ga predpisuje standard [13] za metode, ki temeljijo na “izraèunu z uporabo kataloga”. Iz tega izhaja, da je povpreène letne zunanje temperature in letne periodiène spremembe povpreènih meseènih temperatur mogoèe nadomestiti z zunanjo projektno temperaturo doloèenega kraja.

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An Approach to the Chemosystematics of the Genus Cucumis L.

An Approach to the Chemosystematics of the Genus Cucumis L.

phenolics are characterized by the presence of at least one aromatic ring with one or more hydroxyl groups directly bonded to the ring. They range from the naturally occurring simple, low molecular weight, single-aromatic-ring compounds to the large and complex tannins and derived-polyphenols. The most productive plant metabolic route, in terms of the number of phenolic substances it produces, is the one that leads to the flava-/flavo-noids, a C 6 -C 3 -C 6 framework with close to 10,000 structures characterised to date. Flavonoids, because of their easy isolation, identification, stability and occurrence in different structural forms, have been used extensively for differentiating various species, establishing relationships at inter-generic and sub- familial levels and solving taxonomic problems 13 .
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Automatic room temperature control

Automatic room temperature control

While the enhanced air conditioning system is being designed, the consideration of the type of control system must be included in a modeling design. In particular the controller must be able to avoid the inefficiency of having the air conditioning operate all the time. Several control options were considered at presence sensing circuit, which would turn the air conditioning off when people are not in the room with the air conditioning and a temperature sensor input, which would change the air conditioning operation depending on room temperature [1]. Based on the observation of the using the present conventional air conditioning application, it always working all the time without a systematic control. Therefore, the control of the air conditioning is adjusted through a feedback control system to monitor and maintain a constant temperature based on the data input from the sensor.
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Automatic Room Temperature Controller

Automatic Room Temperature Controller

7 Here (Figure 2.2) is a circuit through which the speed of a fan can be linearly controlled automatically, depending on the room temperature. The circuit is highly efficient as it uses thyristors for power control. Alternatively, the same circuit can be used for automatic temperature controlled AC power control. In this circuit, the temperature sensor used is an NTC thermistor, i.e. one having a negative temperature coefficient. The value of thermistor resistance at 25°C is about 1 kilo-ohm. Op-amp A1 works as current-to-voltage converter and converts temperature variations into voltage variations. Other side, Op-amps A2, A3 and A4 work as an instrumentation amplifier to amplify the change in voltage due to change in temperature [2].
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Simplified Fokker-Plank Equation Treatment of Finite-temperature Spin-torque Problems

Simplified Fokker-Plank Equation Treatment of Finite-temperature Spin-torque Problems

The dynamics of a macrospinunder spin-torque-driven magnetic reversal has been extensively studied. [8-9] In the limit of uniaxial anisotropy only and with finite temperature at large drive amplitude I >> I c0 , with I being the current passing

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An Analytical Determination of the Mean Radiant Temperature for a Complex Room Geometry

An Analytical Determination of the Mean Radiant Temperature for a Complex Room Geometry

Radiative heat losses represent a substantial part of the total heat balance of the human body in a closed space. The correct determination of this contribution is necessary in order to gain an insight into the influence of this parameter on human thermal comfort. The thermal balance is strongly affected by surface temperatures and by the angle factor between a body and a wall surface. Since a room’s internal surfaces are composed of various parts, the calculation of view factors becomes more complex. Therefore, a computer algorithm is a useful tool for determining the radiant heat exchange, particularly for the complex surface compositions encountered in practical situations.
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Classifying superconductivity in ThH-ThD superhydrides

Classifying superconductivity in ThH-ThD superhydrides

where M is isotope mass, and 𝛼 ≈ 1 2 ⁄ (for weak-coupling limit of BCS theory [1]), is central indispensable feature of electron-phonon mediated superconductivity [1]. This effect was observed in several elemental superconductors, but not in all of them [2]. And, for instance, Geballe et al [3] were first who found the absence of the isotope effect in ruthenium (more details can be found elsewhere [2-4]). Later, Satterthwaite and Toepke [5] reported the absence of the isotope effect in Th 4 H 15 -Th 4 D 15 super-hydride/deuteride phases. Soon after

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A Facile Approach of Diels-Alder Reaction in Imidazolium-based Ionic Liquids at Room Temperature

A Facile Approach of Diels-Alder Reaction in Imidazolium-based Ionic Liquids at Room Temperature

In a two-neck round bottom flask, p-toluidine was dissolved in tetrahydrofuran and mixed with maleic anhydride. Mixture was stirred at room temperature under an inert atmosphere overnight. The resulting precipitate was filtered and used in the next step without further purification. The crude p-maleimide acid was suspended in dry acetonitrile. Zinc bromide and HMDS were added to the solution and the resulting reaction mixture was heated at reflux (90°C) for 2 h. The reaction mixture was cooled down at room temperature and filtered. Water was added and the pH of the solution was adjusted to pH1 using 1M HCl. The solution was washed with ethyl acetate, the layers separated and the organic phase dried (MgSO 4 ) 27 . The solution was
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