Деформация тонких пленок полуметаллов методом купольного изгиба подложки

The results of a study of the semimetal films deformation produced by dome bending of the substrate are presented. Deformation control was carried out by means of X-ray diffraction analysis. It is shown that the dome bending method can be used to study films under planar deformation in a film-substrate system with different thermal expansion coefficients. The maximum in-plane deformation for bismuth films of 1 mkm thickness order was found. It was shown that the deformation created by the dome bending of the substrate in combination with the use of substrates with different temperature expansion makes it possible to obtain a relative in-plane deformation of bismuth films up to 0.8% at 300 K.

Study on the Mechanism of Water and Heat Transfer in Sandstone Geothermal System: A Case Study of Doublet Well

The development of sandstone-type geothermal energy is an important part of the development of geothermal resources and has great significance in promoting environmental protection and energy structural transformation. In sandstone geothermal energy development, recharging is the main method to ensure bottom hole pressure. However, the pressure and temperature changes of sandstone reservoirs under recharge conditions have not been extensively studied. It is easy to ignore the hydraulic relationship between the production and the injection wells, which leads to an increased risk of thermal breakthrough. Therefore, a three-dimensional hydrothermal coupling model is established, and simulation studies of different flow rates, well lengths, and well spacings are completed in this paper. Here, we show the numerical simulation results. The low temperature expansion zone and hydrostatic pressure near the injection well increase with increasing flow rate, and the maximum expansion of the low temperature zone is about 350 m. The low temperature expansion area near the injection well has a small relationship with the well spacing, and the increase in hydrostatic pressure is proportional to the well spacing. As the length of the well increases, the increase in hydrostatic pressure near the injection well decreases, indicating that the injected water under the long well section easily enters the reservoir. When no thermal breakthrough occurs and the hydrostatic pressure drops significantly near the production well, it is recommended that the flow rate be controlled at approximately 20–25 L/s, the well spacing should be 600–800 m, and the well length should be greater than 100 m.

ANALYSIS OF LOW-TEMPERATURE EXPANSION PROCESSES OF NON-IDEAL GASES

An energy analysis of the processes of obtaining and using artificial cold in chemical technology is presented. The most well-known methods of obtaining and applying the cooling effect are considered: adiabatic expansion of vapor and gaseous bodies in expanders, throttling. Special attention is paid to the effect of object deviation from the ideal gas model.

Numerical evaluation of expansion loops for pipe subjected to thermal displacements

The thermal expansion can lead to the high stress on the pipe. The problem can be overcome using expansion loops in a certain length depending on the material’s elastic modulus, diameter, the amount of expansion, and the pipe’s allowable stresses. Currently, there is no exact definition for the dimension of expansion loops design both for loop width (W) and loop footing height (H) sizes. In this study, expansion loops were investigated with using ratio of width and height (W/H) variations to understand pipe stress occurring on the expansion loops and the expansion loops’ safety factor. Relationship between non dimensional stress on the expansion loop pipe was studied numerically by finite element software on several working temperatures of 400oF, 500oF, 600oF, and 700oF. It can be found that stress occurring on the pipes increases as the increases of W/H of the expansion loops and results in a lower safety factor. The safety factor of the expansion loops pipe has a value of 1 when the ratio of loop width and loop footing height (W/H) value was 1.2 for a 16-inch diameter pipe. Stress occurring on the pipe increases with the increase of the working temperature. Expansion loops pipe designed for 400oF can still work well to handle thermal extension pipe occurring on 500oF.

E-Module Pada Materi Suhu, Pemuaian, dan Kalor: Valid dan Praktis

Penelitian ini bertujuan untuk mengembangkan e-module pada materi suhu, pemuaian, dan kalor yang valid dan praktis. Metode pengembangan yang digunakan dalam penelitian ini adalah model pengembangan Alessi dan Trollip yang terdiri dari tiga tahapan, pengembangan dengan model Alessi and Trollip, dengan tahapan yaitu tahap perencanaan, tahap desain, dan tahap pengembangan. E-Module pada materi suhu, pemuaian, dan kalor dikembangkan dengan menggunakan program Flip PDF Professional. Setelah melalui tahap perencanaan dan tahap desain, selanjutnya pada tahap pengembangan peneliti melakukan uji Alpha dan uji Beta. Uji Alpha dilakukan untuk mengetahui tingkat kevalidan e-module dengan melibatkan tiga orang ahli untuk mereview dan menilai aspek isi (konten), aspek kebahasaan, serta aspek dasain dan fitur dari e-module yang dikembangkan. Sedangkan uji Beta dilakukan untuk mengetahui tingkat kepraktisan e-module dengan melibatkan enam orang siswa dengan kemampuan kognitif yang berbeda untuk mereview dan menilai aspek kelayakan isi (konten), aspek penyajian, aspek dasain dan fitur, beserta aspek manfaat dari e-module yang dikembangkan. Berdasarkan hasil uji Alpha yang dilakukan oleh tiga orang ahli diperoleh rerata hasil penilaian masing-masing sebesar 4,90; 4,75; dan 4,51; sedangkan melalui uji Beta yang dilakukan oleh enam orang siswa diperoleh rerata hasil penilaian masing-masing sebasar 4,97; 4,78; 4,60; 4,65; 4,81; dan 4,78. Berdasarkan hasil uji Alpha dan uji Beta tersebut maka e-module pada materi suhu, pemuaian, dan kalor yang dikembangkan dinyatakan sangat valid dan sangat praktis. E-Module pada materi suhu, pemuaian, dan kalor yang telah dikembangkan dapat dimanfaatkan oleh siswa dan guru sebagai sarana pembelajaran di sekolah serta sebagai sarana belajar mandiri oleh siswa dirumah. This study aims to develop an e-module on the material of temperature, expansion, and heat that is valid and practical. The methodology of development used in this research is the development model consisting of three stages: the planning stage, the design stage, and the development stage. E-Module was developed using the Flip PDF Professional program on the material of temperature, expansion, and heat. After going through the planning and design stages, the researcher conducted Alpha and Beta tests on the development stage. The Alpha test was conducted to determine the level of validity of the e-module by involving three experts to review and assess the aspects of the content, the linguistic, and the design and features of the developed e-module. Meanwhile, the Beta test was conducted to determine the level of practicality of the e-module by involving six students with different cognitive abilities to review and assess the eligibility of the content, the aspects of presentation, the design, the features, and the benefits of the developed e-module as well. Based on the Alpha test results conducted by three experts, each obtained an average result of 4.90, 4.75, and 4.51. However, the Beta test results were conducted by six students, each obtained an average result of 4.97, 4.78, 4.60, 4.65, 4.81, and 4.78. In conclusion, the Alpha and Beta test results show that the developed e-module on the material of temperature, expansion, and heat is declared to be very valid and very practical. So, e-module has been developed to benefit students and teachers as a learning tool at school and as a means of independent learning by students at home.

Investigation of Temperature Deformations and Burning of Models from Polymers

The usage of 3D printing technology SLA and DLP is promising for obtaining casting models. The article presents the results of a study of temperature deformations, developing during the burning of models from polymers “Fun to Do Castable Blend”, “Oh-All! Red” and “Orange Fluor”. In the performance of the experiments, photopolymer models were exposed to an impact of isothermal at temperatures from 50 to 330 °C, and their linear dimensions measured; changes developing on their surface were noted. It is shown that, with an increase of the isothermal holding temperature, the models expand first and narrow later. It has been linked to temperature expansion and subsequent decomposition of the photopolymer. It is shown that the casting molds ,obtained with the usied thin-walled hollow casting models from these photopolymers, are destroyed at the stage of their burning.

The Low-Temperature Expansion of the Casimir-Polder Free Energy of an Atom with Graphene

We consider the low-temperature expansion of the Casimir-Polder free energy for an atom and graphene by using the Poisson representation of the free energy. We extend our previous analysis on the different relations between chemical potential μ and mass gap parameter m. The key role plays the dependence of graphene conductivities on the μ and m. For simplicity, we made the manifest calculations for zero values of the Fermi velocity. For μ>m, the thermal correction ∼T2, and for μ<m, we confirm the recent result of Klimchitskaya and Mostepanenko, that the thermal correction ∼T5. In the case of exact equality μ=m, the correction ∼T. This point is unstable, and the system falls to the regime with μ>m or μ<m. The analytical calculations are illustrated by numerical evaluations for the Hydrogen atom/graphene system.

Ripples in spacetime from broken supersymmetry

We initiate the study of gravitational wave (GW) signals from first-order phase transitions in supersymmetry-breaking hidden sectors. Such phase transitions often occur along a pseudo-flat direction universally related to supersymmetry (SUSY) breaking in hidden sectors that spontaneously break R-symmetry. The potential along this pseudo-flat direction imbues the phase transition with a number of novel properties, including a nucleation temperature well below the scale of heavy states (such that the temperature dependence is captured by the low-temperature expansion) and significant friction induced by the same heavy states as they pass through bubble walls. In low-energy SUSY-breaking hidden sectors, the frequency of the GW signal arising from such a phase transition is guaranteed to lie within the reach of future interferometers given existing cosmological constraints on the gravitino abundance. Once a mediation scheme is specified, the frequency of the GW peak correlates with the superpartner spectrum. Current bounds on supersymmetry are compatible with GW signals at future interferometers, while the observation of a GW signal from a SUSY-breaking hidden sector would imply superpartners within reach of future colliders.

Calculation and computation

This chapter introduces Monte-Carlo techniques to simulate the equilibrium properties of complex systems, and perturbative techniques to calculate their behavior as an expansion about solvable limits. It uses the Ising model as a description of magnets, of binary alloys, and of the liquid-gas transition. It introduces Markov chains and detailed balance as providing a guarantee that Monte-Carlo methods converge to equilibrium. To analyze phases and phase transitions, it introduces a 27-term low-temperature expansion for the magnetization of the Ising model. Inside phases, perturbation theory converges; at phase transitions, it cannot. Exercises simulate the behavior of the Ising model and cellular function. They explore equilibration algorithms and calculation of low temperature expansions. And they apply Markov chains to coin flips, unicycles, fruit flies, chemical reaction rates, and DNA replication.