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Tungsten-Rhenium (W-Re) thin films were grown on alumina ceramic substrate using the magnetron sputtering technique. The feasibility and reliability of the tungsten-rhenium thin film thermocouples application are largely dependent on the adhesion properties between the W-Re film and substrate. In order to get the good adhesion, we researched the effect of magnetron sputtering parameters on adhesion properties of tungsten-rhenium thin film thermocouples. With the help of three factors and three levels orthogonal table, nine orthogonal experiments were designed to study the influences of argon flow rate, sputtering power and vacuum degree on the performance of adhesion. The result showed that the effect of vacuum degree on adhesion properties was the largest, then come sputtering power, while the effect of the argon flow rate was the least and the optimal parameters combination was: argon flow rate 30 Sccm, sputtering power 400 W and vacuum degree 0.7 × 10−6 Torr.

A tungsten-rhenium thin film thermocouples (TFTCs) with ceramic substrate is fabricated and measured in order to establish temperature testing systems. The property of TFTCs with different kind of substrates are measured by and analyzed. The static temperature retention experiment is done to test the thermoelectric characteristics. The experiments showed that TFTCs work at 950K.

The working time of tungsten-rhenium (W-Re) thin film thermocouples (TFTCs) is reduced for the reason of heat volatilization under non oxidizing environment. Influence of magnetron sputtering parameters on thermal volatilization property of tungsten-rhenium TFTCs were discussed by aging test and scanning electron microscope (SEM) test. We used different gas flow rate, sputtering power and the vacuum degree to make 9 samples of TFTCs film. The aging experiment showed that the suitable magnetron sputtering parameters can reduce the heat volatilization rate to 46.5nm/h.

The tungsten-rhenium thin film thermocouples (TFTCs) sensor is designed and optimized based on mechanical properties analysis, the process is optimal designed and the experiment shows the working hours of TFTCs sensor with optimal increasing from 10 minutes to 300 minutes at 900K, and the total work time reach to 600 minutes with a better output voltage when compared with our previously published work and the typically type-S wire thermocouple. Nano-indentation and numerical analysis was used to get the mechanical properties of tungsten-rhenium thin film to make the optimal designed for the dimension parameter of TFTCs. Heat treatment was used to improve the film quality, and the post-processing module was designed to compensate the cold junction temperature and record data. Static thermal test was done to confirm the performance of TFTCs.

A thermal stress range analysis of tungsten-rhenium thin film thermocouples based on ceramic substrates is presented to analyze the falling off and breakage problems caused by the mismatch of the thermal stresses in thin film thermocouples (TFTCs) and substrate, and nano-indentation experiments are done to measure and calculate the film stress to compare with the simulation results. Optimal design and fabrication of tungsten-rhenium TFTCs based on ceramic substrates is reported. Static high temperature tests are carried out, which show the optimization design can effectively reduce the damage caused by the thermal stress mismatch.

In this paper, Nano-indentation technology is used to test the mechanical property of the tungsten-rhenium thin film, including hardness, elastic modulus and residual stress. The effects of different heat treatment temperature and different substrates on the hardness and elastic modulus of tungsten-rhenium films were studied. We research three substrates which are silicon carbide ceramic, aluminum oxide ceramic and zirconium oxide ceramic. Test results show that the tungsten-rhenium films on aluminum oxide ceramic shows the biggest values of elastic modulus and the smallest on silicon carbide ceramic. However, value of hardness is biggest on zirconium oxide ceramic and smallest on aluminum oxide ceramic. Besides, the heat treatment temperature has high influence on hardness and elastic modulus of tungsten-rhenium film. And under different substrates, the hardness and elastic modulus of film on zirconium oxide ceramic is the most sensitive to heat treatment temperature. By contrast, silicon carbide ceramic is the least.

A tungsten-rhenium thin film thermocouples is designed and fabricated, and the characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. Protective film was presented to prevent from the oxidation and evaporation of tungsten-rhenium TFTCs at high temperature. The experiment shows TFTCs sensor with protective film have an acceptable linearity up to 1370K with a suitable voltage output and can work for half an hour at 1370K, however the TFTCs without protective films break after high temperature constant at 900K.

A tungsten-rhenium thin film thermocouple is designed and fabricated, depending on the principle of thermal-electric effect caused by the high temperature. The characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. The working mechanism and thermo-electric features of the thermocouples are analyzed depending on the simulation results. Then the thin film thermocouples are fabricated and calibrated. The calibration results show that the thin film thermocouples based on the tungsten-rhenium material achieve ideal static characteristics and work well in the practical applications.

The electron-transfer kinetics for each of three copper(II/I) tripodal ligand complexes reacting with multiple reducing and oxidizing counter reagents have been examined in aqueous solution at 25 degrees C, mu = 0.10 M. For all of the ligands studied, an amine nitrogen serves as the bridgehead atom. Two of the ligands (PMMEA and PEMEA) contain two thioether sulfurs and one pyridyl nitrogen as donor atoms on the appended legs while the third ligand (BPEMEA) has two pyridyl nitrogens and one thioether sulfur. Very limited kinetic studies were also conducted on two additional closely related tripodal ligand complexes. The results are compared to our previous kinetic study on a Cu(II/I) system involving a tripodal ligand (TMMEA) with thioether sulfur donor atoms on all three legs. In all systems, the Cu(II/I) electron self-exchange rate constants (k(11)) are surprisingly small, ranging approximately 0.03-50 M(-)(1) s(-)(1). The results are consistent with earlier studies reported by Yandell involving the reduction of Cu(II) complexes with four similar tripodal ligand systems, and it is concluded that the dominant reaction pathway involves a metastable Cu(II)L intermediate species (designated as pathway B). Since crystal structures suggest that the ligand reorganization accompanying electron transfer is relatively small compared to our earlier studies on macrocyclic ligand complexes of Cu(II/I), it is unclear why the k(11) values for the tripodal ligand systems are of such small magnitude.

The absolute magnitude of an "entatic" (constrained) state effect has never been quantitatively demonstrated. In the current study, we have examined the electron-transfer kinetics for five closely related copper(II/I) complexes formed with all possible diastereomers of [14]aneS(4) (1,4,8,11-tetrathiacyclotetradecane) in which both ethylene bridges have been replaced by cis- or trans-1,2-cyclohexane. The crystal structures of all five Cu(II) complexes and a representative Cu(I) complex have been established by X-ray diffraction. For each complex, the cross-reaction rate constants have been determined with six different oxidants and reductants in aqueous solution at 25 degrees C, mu = 0.10 M. The value of the electron self-exchange rate constant (k(11)) has then been calculated from each cross reaction rate constant using the Marcus cross relation. All five Cu(II/I) systems show evidence of a dual-pathway square scheme mechanism for which the two individual k(11) values have been evaluated. In combination with similar values previously determined for the parent complex, Cu(II/I)([14]aneS(4)), and corresponding complexes with the two related monocyclohexanediyl derivatives, we now have evaluated a total of 16 self-exchange rate constants which span nearly 6 orders of magnitude for these 8 closely related Cu(II/I) systems. Application of the stability constants for the formation of the corresponding 16 metastable intermediates--as previously determined by rapid-scan cyclic voltammetry--makes it possible to calculate the specific electron self-exchange rate constants representing the reaction of each of the strained intermediate species exchanging electrons with their stable redox partners--the first time that calculations of this type have been possible. All but three of these 16 specific self-exchange rate constants fall within--or very close to--the range of 10(5)-10(6) M(-1) s(-1), values which are characteristic of the most labile Cu(II/I) systems previously reported, including the blue copper proteins. The results of the current investigation provide the first unequivocal demonstration of the efficacy of the entatic state concept as applied to Cu(II/I) systems.