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Hefei Advanced Light Facility (HALF) will use a 499.8MHz superconducting cavity to provide energy for the beam in the storage ring. The fundamental power coupler (FPC) needs to feed 140kW RF power into the superconducting cavity. In order to meet the requirements of the HALF project, a 499.8MHz FPC prototype was developed at the National Synchrotron Radiation Laboratory (NSRL). This paper presents the design of the FPC prototype. The fabrication process of the FPC prototype will also be described. The cold test of the FPC prototype room-temperature test stand was carried out. The results show that the cold test performance of the FPC prototype meets the requirements and it can be tested with high power. The high power test of the FPC prototype will be carried out in the future.

It is found in oxygen there are a weight loss and an endothermal anomaly in compound of Y_1-xCa_xBa₂Cu₃O_y starting at about 320 °C, while in nitrogen at about 370 °C and a mixed atmosphere, N₂(50%)+O₂(50%), at about 350 °C. The results are different from those in undoped YBa₂Cu₃O_y and some doped systems. It is suggested that Ca prefers a sixfold coordination, which causes the oxygen loss in Cu(2)-O plane and the weight and heat anomalies at different temperature in different atmospheres. The oxygen loss in Cu(2)-O plane is also responsible for T_c suppression in Y_1-xCa_xBa₂Cu₃O_y.

Plastics is commonly used in consumer electronics because of it is high strength per unit mass and good productivity, but plastic components may often become distorted after injection molding due to residual stress after the filling, packing, and cooling processes. In addition, plastic deteriorates depending on various temperature conditions and the operating time, which can be characterized by stress relaxation and creep. The viscoelastic behavior of plastic materials in the time domain can be expressed by the Prony series using the ABAQUS commercial software package. This paper suggests a process for predicting post-production deformation under cyclic thermal loading. The process was applied to real plastic panels, and the deformation predicted by the analysis was compared to that measured in actual testing, showing the possibility of using this process for predicting the post-production deformation of plastic products under thermal loading.

The semi-organic 3-aminophenol-orthophosphoric acid (denoted as 3-amphph) single crystals were grown by slow evaporation solution technique with water as solvent. The resulted crystal has well-defined surface morphology and is transparent and colorless with a size of 29 × 17 × 4 mm³. The powder X-ray diffraction (XRD), NMR spectroscopic technique, UV-vis-NIR, TG/DTA and dielectric analysis are used to characterize the crystals. XRD analysis revealed that the crystal lattice of 3-amphph is orthorhombic having cell parameters a = 4.481(2) Å, b = 9.782(4) Å, c = 18.326(4) Å with non-centrosymmetric space group P2₁2₁2₁. Nonlinear optical studies indicated that the second harmonic generation (SHG) efficiency is 2.22 times that of the standard potassium dihydrogen phosphate (KDP) crystals. Growth mechanism and surface textures of the as-grown single crystals were analyzed by chemical etching analysis.

In this paper, an organic 4-nitroaniline picrate (4NP) single crystal was grown by solution growth method. Single crystal X-ray diffraction study revealed that grown crystal belongs to orthorhombic system with Pbcn space group. The solid state constants such as plasma energy, Penn gap, Fermi energy and polarizability of 4NP crystal were determined theoretically. The functional groups of the grown crystals were confirmed qualitatively from FTIR spectral analysis. The thermal decomposition and melting point of the crystal were determined from thermogravimetric analysis. The optical absorption and cut-off wavelength of the crystal were determined from UV-visible study. The second harmonic generation (SHG) efficiency of the grown crystal was measured by Kurtz–Perry SHG test using Nd:YAG laser. The laser damage threshold value of the grown crystal was estimated by multi-shot method using 1064 nm laser.

As ammonium dihydrogen phosphate (ADP) is a popular nonlinear optical crystal, to engineer its linear and nonlinear optical properties, the chalcogenide compound cobalt sulphide (CoS) was doped and the crystals were grown by the slow solvent evaporation method. To increase the solubility of CoS in water, its nanoparticles were synthesized by wet chemical technique using ethylene diamine as the capping agent followed by microwave irradiation. The nanoparticle sample exhibited finite solubility in water and was used to dope in ADP crystals. The powder XRD patterns showed the single phase nature of the doped crystals. The FTIR spectra confirmed the presence of various functional groups and EDAX gave the estimation of Co and S elements. The EPR spectroscopy also confirmed the presence of cobalt in the doped samples. TGA indicated slightly less thermal stability of the doped crystals compared to the pure ADP. The dielectric study was carried out at room temperature in the frequency range from 100Hz to 1MHz. Also, various linear optical parameters were evaluated for pure and doped crystals using UV–Vis spectroscopy. The second harmonic generation (SHG) efficiency of Nd:YAG laser was evaluated by the Kurtz and Parry method for the doped samples, it was found to be slightly lesser than that of the pure ADP crystals.

During the sputtering-deposition process, the temperature of film growth surface is more important than that of the substrate, which could seriously influence the film growth behavior. While, it is difficult to measure the temperature of film growth surface, because of the low space resolution of traditional temperature measurement systems. In this paper, the temperature of TiO₂ film growth surface and substrate were monitored by the home-made NiCr/NiSi film thermocouple and standard NiCr/NiSi K type wire thermocouple. With the same sputtering parameters, the temperature of TiO₂ film growth surface could reach $846.2\pm 3.9^{\circ }$C. While, the temperature of substrate was only about $305.8\pm 1.4^{\circ }$C. Finally, combining the temperature of film growth surface in sputtering-deposition process, the film growth behavior can be investigated and controlled in future.

High-performance three-dimensional integrated circuits (3D ICs) are now severely constrained by the thermal issue resulting from the high-power density and limited thermal conductivity among vertically stacked chips. The power distribution networks (PDNs) in 3D ICs are composed of good thermal conductors, but several existing methods are unable to demonstrate their heat dissipation effect successfully, and the thermal models of 3D ICs currently used are either incomplete or have significant errors. In this paper, the Adaptive Unit Difference Iterative (AUDI) method is proposed to establish the equivalent thermal model which can characterize the temperature distribution of 3D ICs accurately. Compared with the simulation results from the Finite Element Method (FEM) tool, the proposed model improves the computational efficiency greatly, and the error in temperature responses is within 3%. The model is used to analyze the effect of 3D PDNs parameters on temperature characteristics and the priority of temperature optimization is indicated, which is of significance for the thermal design.

Gravity can be studied in detail in near Earth orbits NEO's using laser-ranged test masses tracked with few-mm accuracy by ILRS. The two LAGEOS satellites have been used to measure frame dragging (a truly rotational effect predicted by GR) with a 10% error. A new mission and an optimized, second generation satellite, LARES (I. Ciufolini PI), is in preparation to reach an accuracy of 1% or less on frame dragging, to measure some PPN parameters, to test the 1/r² law in a very weak field and, possibly, to test select models of unified theories (using the perigee). This requires a full thermal analysis of the test mass and an accurate knowledge of the asymmetric thermal thursts due to the radiation emitted by the Sun and Earth. A Space Climatic Facility (SCF) has been built at INFN-LNF (Frascati, Italy) to perform this experimental program on LAGEOS and LARES prototypes. It consists of a 2 m × 1 m cryostat, simulators of the Sun and Earth radiations and a versatile thermometry system made of discrete probes and an infrared digital camera.

The SCF commissioning is well underway. A test of all its subsystems has been successfully completed on August 4, 2006, using a LAGEOS 3 × 3 retroreflector array built at LNF. This prototype has been thermally modeled in detail with a commercial simulation software. We expect to demonstrate the full functionality of the SCF with the thermal characterization of this LAGEOS array by the beginning of September 2006.

Porous fins with temperature-dependent internal heat generation are frequently used to improve performance in a wide range of heat transfer and porous media applications. Thermal analysis of the porous fin fractal model with temperature-dependent heat generation is generated using fractal derivatives and investigated analytically using a novel Maclaurin series method (MSM). Nonlinear temperature distribution in a porous longitudinal fin is produced by the MSM. The porous fin solution is demonstrated using the Sierpinski fractal, which is based on time-dependent heat generation. The effects of the convection parameter, porosity, internal heat production, and generation number parameter on the dimensionless temperature distribution are discussed. MSM results are graphically and tabularly compared to existing solution methods such as HPM, CM, CSCM, LWCM, and GWRM. A comparison study reveals that MSM is a very reliable, accurate, and effective addition in the field of differential equations.

Single crystals of zinc sulfate doped L-alanine (LAZ) were grown by adopting the slow evaporation technique at room temperature. The crystal structure of LAZ was determined using single-crystal X-ray diffraction. The functional groups of LAZ were identified by FT-IR spectroscopy analysis. UV–Visible–NIR transmittance study was carried out, and the bandgap energy was found. A fluorescence study was performed to get the emission spectrum of the LAZ crystal. The Vickers microhardness test is used to determine the LAZ crystals mechanical behavior. Thermogravimetric and differential thermal analyses have also been studied to investigate the thermal property of the LAZ crystal. The efficiency of the title crystal’s second harmonic generation (SHG) was investigated. The electrical properties were estimated by impedance study.

The new organic 2-amino-5-chloropyridinium phenoxyacetate (2A5CPA) nonlinear optical (NLO) crystal was synthesized and grown from methanol solvent by slow evaporation method successfully. The complete 2A5CPA crystal structure was solved by single crystal XRD analysis and it indicates that the 2A5CPA crystal belongs to the tetragonal crystal system with the space group P4₁2₁2. From the structure, the possible hydrogen bonding interactions have been analyzed. The presence of distinctive functional peaks in the 2A5CPA crystal was affirmed by FTIR analysis. The optical investigation reveals that the crystal was completely transparent in the UV–Vis–NIR region. The TG-DTA investigation assured that the 2A5CPA compound is thermally stable up to 134°C without any decomposition. The sharp endo thermic peak at 205°C in the DTA trace indicates the melting point of the crystal. The broad emissive band at 382nm implies the violet emission characteristics of the 2A5CPA crystal. The dielectric study of the 2A5CPA crystal portrays the normal behavior to that of optical materials. The high work-hardening coefficient of 2.94 indicates the soft material nature of the crystal. The LDT value of the 2A5CPA crystal is estimated as 0.6135GW/cm². The third-order NLO properties of the 2A5CPA crystal were analyzed through Z-Scan experiment.

Carbon nanotubes (CNTs) have emerged as efficient tools in drug delivery systems; therefore, it is essential to refer to the importance of the magnetic field, in addition to the fluid flow on the dynamic behavior of CNTs. Additionally, in such medical applications, the actual working environment of nanotube often contains temperature changes, and CNTs are surrounded by soft tissues with viscoelastic mechanical properties. In this study, the vibrational behavior of CNTs conveying magnetic-fluid flow and resting on a viscoelastic foundation is investigated under various temperature variations. To incorporate the influence of slip velocity at the nanoscale, a correction factor is employed on the basis of the Beskok–Karniadakis model. The nanotube is modeled by the Euler–Bernoulli beam theory, and governing equations of motion are derived by implementing Hamilton’s principle based on Eringen’s nonlocal elasticity theory. Results indicate that by applying a magnetic field with an intensity of 30T, the dimensionless critical flow velocity increases from 4.345 to 12.603. Also, the critical flow velocity shows an increase from 4.345 to 5.854 in the presence of a viscoelastic foundation. Furthermore, a temperature variation equal to 20K reduces the critical flow velocity dramatically from 4.345 to 1.802 at low temperatures, while an increase from 4.345 to 5.443 is observed at high temperatures. Consequently, while the magnetic field and the viscoelastic foundation affect the system stability, the temperature variation may improve or deteriorate the stability. Therefore, to plan for a medical application, the inclusion of temperature variation is required.

This study focuses on the vibration characteristics of the functionally graded materials (FGMs) porous plate. The plate is to be supported on different boundary constraints with linearly varying thicknesses. Existence of different porosity (void) pattern, within the materials, are taken into consideration using the power (P-FGM) and sigmoidal (S-FGM) gradation laws. The current methodology was developed utilizing the FSDT (first-order shear deformation theory) under thermal environmental conditions. Variations of temperature like as uniform, linearly varying, and nonlinear distribution patterns were examined by including temperature-dependent and independent material properties. The equations of motion including all the effects are derived from Hamilton’s principle and, subsequently solved using the Galerkin’s Vlasov method for various plate boundary conditions. Finally, the analytical outcomes are verified numerically, with the existing works. Furthermore, the study demonstrates that the fundamental frequency of porous FGM tapered plate is very close to the result obtained by the other researchers. Moreover, a detailed examination has been carried out to reveal the effect of various factors such as volume exponent index ($\mathbb{N})$, side-to-thickness ratio ($a$/$h)$, and temperature effect ($T)$. In addition to this, some new benchmark results are obtained for free vibration analysis of tapered plates under a thermal environment.

Electric-arc discharge deposition (EADD) is used to produce CNT products. The design and electric scheme are discussed in details, as well as all technological features. The results of the outputs of all technological schemes are discussed on the basis of thermal analysis (TGA and DTA), supported by TEM and fullerene-dissolving tests. It is established that CNTs mainly form as compact cathode deposits ("stubs"). Conditions of stub preferential growth are experimentally defined. These conditions have narrow range of parameters that may cause some difficulties in scaling of CNT production.

Carbonaceous nanotubes with a calculated specific heat of 710J K${}^{-1}$ Kg${}^{-1}$, and an outer diameter of 58nm, made by a micro-thermal reaction, using polypyrrole nanotubes precursor is presented here. Three degradation stages from the thermal curves are identified. We observe a decomposition temperature at 371${}^{\circ }$C that relates to the presence of amorphous carbon on samples for the first time in this material. Also, it is identified that gradual decomposition of the fragments provides a different kind of residue percentage in the range 48–32% that is related to stirring speed used in each synthesis. It is worthy to note that electron transmission microscope images of carbonaceous nanotubes present defects as well, wherein we identify chloride and nitrogen as doped agents. Finally, results of nanotubes using Infrared, Raman spectrometry analysis, scanning electron microscopy and electron diffraction are presented here.

Thermal analysis can be used as one of the basis for the friction pair material selection in high-speed friction braking system. In this study, the experimental results showed that surface temperature could be reduced by increasing the radius of the friction disk or thermal conductivity coefficient of disk material with stable braking; In the early stage of long braking, the temperature on the friction surface rises rapidly, but further braking does not lead to a significant rise in temperature; In the case of short braking, there is not enough time for the friction surface to reach the critical temperature, and the disk surface reaches the maximum temperature at the end of braking. During long braking, the dimensionless time capacity of the friction surface reaching the highest temperature is F₀ ≈ 0.1F_0s.

Industrial transformer is one of the most critical assets in the power and heavy industry. Failures of transformers can cause enormous losses. The poor joints of the electrical circuit on transformers can cause overheating and results in stress concentration on the structure which is the major cause of catastrophic failure. Few researches have been focused on the mechanical properties of industrial transformers under overheating thermal conditions. In this paper, both mechanical and thermal properties of industrial transformers are jointly investigated using finite element analysis (FEA). Dynamic response analysis is conducted on a modified transformer FEA model, and the computational results are compared with experimental results from literature to validate this simulation model. Based on the FEA model, thermal stress is calculated under different temperature conditions. These analysis results can provide insights to the understanding of the failure of transformers due to overheating, therefore are significant to assess winding fault, especially to the manufacturing and maintenance of large transformers.

Applications for heat exchangers are many and include power plants, air conditioning, chemical and chemical engineering, and other scientific fields. The cost of materials and energy has increased recently, placing pressure on heat exchangers to become even more efficient. In mechanical design, this work proposes a hybrid method for heat transfer optimization and thermal analysis. The proposed hybrid method is the joint execution of both the Wild Horse Optimizer (WHO) and Multi Fidelity Deep Neural Network (MFDNN). It is hence known as the WHO–MFDNN approach. This proposed technique’s goal is to minimize the system’s overall operating costs while optimizing the system’s efficacy. The MFDNN technique is used to forecast the system’s ideal solution, while the proposed WHO approach is employed to minimize the system’s overall operating costs. By then, the proposed approach has been implemented into the MATLAB working platform, and the existing technique is used to compute the execution. In every system now in use, like Artificial Neural Network (ANN), Wild Border Collie Optimization (BCO) and Particle Swarm Optimization (PSO) the proposed approaches produce superior results. It concludes that the proposed method offers superior performance by achieving a cost of $40, converging in just 200 iterations, and requiring only 10 s of computational time, significantly outperforming existing methods with higher costs and longer convergence and computation times.

The oxidative polycondensation reaction conditions of 4-m-tolylazomethinephenol (4-TAMP) in the presence of air O₂ and NaOCl as oxidants were studied in an aqueous alkaline medium between 50 and 90°C. The structures of the obtained monomer and oligomer were confirmed by FT-IR, UV-Vis, ¹H- and ¹³C-NMR and elemental analysis techniques. The physical characterization was made by TG-DTA, size exclusion chromatography (SEC) and solubility tests. At the optimum reaction conditions, the yield of oligo-4-m-tolylazomethinephenol (O-4-TAMP) was found to be 62.50% (for air O₂ oxidant) and 90.0% (for NaOCl oxidant), respectively. According to the SEC analysis, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of O-4-TAMP were found to be 2310, 2610 g mol^-1 and 1.13, respectively, using air O₂, and 1390, 1710 g mol^-1 and 1.23, using NaOCl, respectively. According to TG-DTA analyses, O-4-TAMP was more stable than 4-TAMP against thermal decomposition. The weight losses of 4-TAMP and O-4-TAMP were found to be 68% and 58% at 1000°C. Electrical conductivity of the O-4-TAMP was measured, showing that the polymer is a typical semiconductor. Electrochemically, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and electrochemical energy gaps (E′_g) for 4-TAMP are -5.96, -3.22 and 2.74 eV, respectively. The HOMO, LUMO and (E′_g) for O-4-TAMP are -5.78, -3.44 and 2.34 eV, respectively. According to UV-Vis measurements, optical band gaps (E_g) of 4-TAMP and O-4-TAMP were found to be 3.45 and 3.10 eV, respectively.