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Polysubstituted Ligand Construction regarding Color Tuning Phosphorescent Iridium(Three) Processes.
6%, and its power gain is 86 dB. The designed radial combiner is highly efficient (power-combining efficiency of 98.4%), and the directional coupler exhibits a very low loss (insertion loss of 0.05 dB).In this paper, an effort has been made to compile various research investigations done so far on fast response gauges for the short duration measurement in the transient state. The review paper is not only about summarization of all-important research work; rather, a detailed review on the development of the fast response gauges, its application, and various methods of heat estimation from the measured transient temperature history is also presented. Before discussing the development of fast response gauges, various heat flux measurement techniques and newer trends in heat transfer gauges are presented. The focus of this Review is mainly on the thin-film gauge, a robust fast response temperature detector best suited for the short duration measurement. The literature on the application of thin-film gauges for various engineering systems such as turbomachinery and aerodynamic heating systems is broadly categorized as single-layered and multi-layered gauges. The applications for the internal combustion engine and low heat flux measurement are also discussed later. The summary tables with studies arranged in chronological order are also provided. Finally, the estimation of the heat transfer rate from the measured transient temperature data is presented.Transverse coupled bunch instability (TCBI) is a major concern at high beam current operations at all synchrotron light sources. Techniques for the mitigation of TCBI include higher order mode tuning of RF cavities, optimization of vacuum chamber designs, increasing the damping rate of beam oscillations, optimization of betatron tune values, and multi-bunch feedback systems. Due to uncertainties, time-variation, and disturbances, the dynamic behavior of accelerators requires further tuning of beam parameters beyond theory-based set points for minimizing the transverse coupled bunch mode (TCBM) instability. In this work, an artificial neural network (ANN) based system is developed to minimize average TCBM levels in the Indus-2 synchrotron light source at the Raja Ramanna Centre for Advanced Technology in Indore, India. The ANN is trained based on various TCBM measurements collected at the Indus-2 for various values of betatron tune and chromaticity in order to learn how to map beam measurements directly to parameters such as optimal betatron tunes and chromaticity values that are sent to a beam feedback control system. The ANN takes as input real-time beam data and is coupled to a feedback controller, thereby creating an adaptive feedback that is able to adjust in real time to variation of the accelerator and beam. We provide a detailed overview of our approach as well as experimental results in which the ANN-guided feedback approach increases the operational beam current of Indus-2 from a limit of ∼170 mA up to ∼230 mA within ∼21 min. We believe that this general method can be useful for a wide range of synchrotron sources operating at high bunch currents.Conventionally, the evaluation of shear failure of discontinuities in rocks and other geomaterials has been conducted under static shear loading. In such methods, the shear failure behaviors of rock discontinuities are significantly influenced by loading velocities. To evaluate the shear failure process under dynamic loading, in this paper, we propose a new experimental methodology by taking advantages of recently available high-speed optical and mechanical measurement techniques. The methodology utilizes the Hopkinson bar to apply impact loading, and the diagnostics include a dynamic stress wave acquisition system, a digital image correlation (DIC) system, and an acoustic emission (AE) monitoring system. click here To improve the accuracy of the DIC analysis, an advanced digital speckle pattern and an updated water transfer printing are used to obtain the optimized and consistent speckle pattern. A flexible piezoelectric film sensor is first introduced to acquire AE signals in order to locate AE events accurately. A dynamic impact shear experiment indicates that the normal stress has a significant effect on the peak shear stress of rock discontinuities and the peak shear stress itself is rate dependent. The displacement field along shear directions is quantified using the DIC method, and the initial AE source locations during the impact shear process are determined using the AE monitoring system. We thus conclude that the dynamic impact shear system can systematically characterize the dynamic impact shear process with quantitative details and can further be implemented to study other dynamic impact failure behaviors of rock discontinuities under in situ stresses.A simultaneous three-dimensional (3D) surface profile and pressure measurement method that integrates phase-shift profilometry and pressure-sensitive paint (PSP2) is proposed. The advantages of this novel technique over previous 3D pressure-sensitive paint (3D-PSP) techniques include a simplified system with low cost, no interference with PSP coatings, high spatial resolution, and high accuracy. A modified digital light-processing (DLP) projector-structured light generator is used to encode ultraviolet light and generate fringe projection to excite the pressure-sensitive paint. The 3D profile is reconstructed using four phase-shifting emission images. Meanwhile, the surface intensity ratio distribution is obtained. The PSP2 method is applied to a nitrogen jet impingement experiment onto a spherical model. The intensity ratio results obtained using the PSP2 method differ little from the conventional PSP results obtained using uniform excitation. The phase distortion due to the emission intensity fluctuation leads to errors in surface profile measurement, and the fringe projection with high contrast improves surface profile measurement accuracy. In most of the final results, the average total errors between the reconstructed 3D surface and the CAD geometry are less than 0.1 mm.A new method for profile measurements of small transverse size beams by means of a vibrating wire is presented. link2 A vibrating wire resonator with a new magnetic system was developed and manufactured to ensure that the wire oscillated in a single plane. Presented evidence gives us confidence that the autogenerator creates vibrations at the natural frequency of the wire in a plane of the magnetic system, and these vibrations are sinusoidal. The system for measuring the laser beam reflected from the vibrating wire by means of a fast photodiode was upgraded. The experiments allowed the reconstruction of a fine structure of the focused beam of the semiconductor laser using only a few vibrating wire oscillations. The system presented here would eventually enable the implementation of tomographic measurements of the thin beam profile.We present a framework for training artificial neural networks (ANNs) as surrogate Bayesian models for the inference of plasma parameters from diagnostic data collected at nuclear fusion experiments, with the purpose of providing a fast approximation of conventional Bayesian inference. Because of the complexity of the models involved, conventional Bayesian inference can require tens of minutes for analyzing one single measurement, while hundreds of thousands can be collected during a single plasma discharge. The ANN surrogates can reduce the analysis time down to tens/hundreds of microseconds per single measurement. The core idea is to generate the training data by sampling them from the joint probability distribution of the parameters and observations of the original Bayesian model. The network can be trained to learn the reconstruction of plasma parameters from observations and the model joint probability distribution from plasma parameters and observations. Previous work has validated the application of such a framework to the former case at the Wendelstein 7-X and Joint European Torus experiments. link3 Here, we first give a description of the general methodological principles allowing us to generate the training data, and then we show an example application of the reconstruction of the joint probability distribution of an effective ion charge Zeff-bremsstrahlung model from data collected at the latest W7-X experimental campaign. One key feature of such an approach is that the network is trained exclusively on data generated with the Bayesian model, requiring no experimental data. This allows us to replicate the training scheme and generate fast, surrogate ANNs for any validated Bayesian diagnostic model.A four-tip electrostatic probe is constructed to measure high-frequency (0.1-10 MHz) fluctuations in both the electric field (one component) and electron density in a laboratory plasma. This probe also provides data for the local electron temperature and density. Circuits for high-frequency measurements are fabricated on two miniature boards, which are embedded in the probe shaft, near the tips to minimize the pickup of common-mode signals. The amplitude and phase response of two circuits to sinusoidal test signals are measured and compared with results from modeling. For both circuits, the phase shift between input and output signals is relatively small ( less then 30°). The performance of the probe is verified in a high-density (∼1013 cm-3) and low-temperature (≲10 eV) plasma. The probe successfully measures high-frequency (∼2 MHz) fluctuations in the electric field and density, which are associated with lower hybrid drift waves. This probe can provide information on the wave-associated anomalous drag, which can be compared with the classical resistivity.We present a design for an atomic oven suitable for loading ion traps, which is operated via optical heating with a continuous-wave multimode diode laser. The absence of the low-resistance electrical connections necessary for Joule heating allows the oven to be extremely well thermally isolated from the rest of the vacuum system. Extrapolating from high-flux measurements of an oven filled with calcium, we calculate that a target region number density of 100 cm-3, suitable for rapid ion loading, will be produced with 175(10) mW of heating laser power, limited by radiative losses. With simple feedforward to the laser power, the turn-on time for the oven is 15 s. Our measurements indicate that an oven volume 1000 times smaller could still hold enough source metal for decades of continuous operation.We create a pair of symmetric Bitter-type electromagnet assemblies capable of producing multiple field configurations including uniform magnetic fields, spherical quadruple traps, or Ioffe-Pritchard magnetic bottles. Unlike other designs, our coil allows both radial and azimuthal cooling water flows by incorporating an innovative 3D-printed water distribution manifold. Combined with a double-coil geometry, such orthogonal flows permit stacking of non-concentric Bitter coils. We achieve a low thermal resistance of 4.2(1) °C kW-1 and high water flow rate of 10.0(3) l min-1 at a pressure of 190(10) kPa.Achieving a high time resolution is highly desirable for revealing the electron dynamics and light-induced phenomena in time- and angle-resolved photoemission spectroscopy (TrARPES). Here, we identify key factors for achieving the optimum time resolution, including laser bandwidth and optical component induced chirp. A full diagnostic scheme is constructed to characterize the pulse duration and chirp of the fundamental beam, second harmonic, and fourth harmonic, and prism pairs are used to compensate for the chirp. Moreover, by using a Sb2Te3 film as a test sample, we can achieve a high test efficiency for the time resolution during the optimization process. An optimized time resolution of 81 fs is achieved in our TrARPES system with a high repetition rate tunable from 76 to 4.75/n MHz.
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