Unveiling the Diffusion-Controlled Operation Mechanism of All-in-One Type Electrochromic Supercapacitors: Overcoming Slow Dynamic Response with Ternary Gel Electrolytes

In this paper, a fuel cell power system is considered to supply DC power for a Peltier based cooling process. For the fuel cell, there exist slow dynamic response and soft characteristic due to long-running. Therefore, the fuel cell hybrid power system is designed, including fuel cell, battery, unidirectional DC-DC converter and bidirectional DC-DC converter. In order to reduce the slow dynamic response and soft characteristic, it is the most important that the bidirectional DC-DC converter is controlled for charging or discharging to the battery. A control scheme combined feedforward and feedback is proposed for the bidirectional DC-DC converter, where feedforward control is based on the output voltage of the fuel cell. Simulation results based on the designed circuit and proposed method are given to verify the performance of the converter.

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A TEM investigation of a hyper-eutectic lead-tin alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010487x ◽

1988 ◽

Vol 46 ◽

pp. 562-563

Author(s):

John A. Sutliff

Keyword(s):

Volume Diffusion ◽

Eutectic Mixture ◽

Precipitation Reaction ◽

Directionally Solidified ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Diffusion Controlled ◽

Discontinuous Precipitation Reaction ◽

Controlled Precipitation

Near-eutectic Pb-Sn alloys are important solders used by the electronics industry. In these solders, the eutectic mixture, which solidifies last, is the important microstructural consituent. The orientation relation (OR) between the eutectic phases has previously been determined for directionally solidified (DS) eutectic alloys using x-ray diffraction or electron chanelling techniques. In the present investigation the microstructure of a conventionally cast, hyper-eutectic Pb-Sn alloy was examined by transmission electron microscopy (TEM) and the OR between the eutectic phases was determined by electron diffraction. Precipitates of Sn in Pb were also observed and the OR determined. The same OR was found in both the eutectic and precipitation reacted materials. While the precipitation of Sn in Pb was previously shown to occur by a discontinuous precipitation reaction,3 the present work confirms a recent finding that volume diffusion controlled precipitation can also occur.Samples that are representative of the solder's cast microstructure are difficult to prepare for TEM because the alloy is multiphase and the phases are soft.

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Quantitative surface damage studies by H.R.E.M.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015513x ◽

1989 ◽

Vol 47 ◽

pp. 632-633

Author(s):

S. R. Singh ◽

H. J. Fan ◽

L. D. Marks

Keyword(s):

Solar Wind ◽

Quantitative Analysis ◽

Surface Science ◽

Surface Damage ◽

Space Environment ◽

Oxygen Desorption ◽

The Past ◽

Diffusion Controlled ◽

Original Observation ◽

Substantial Interest

Since the original observation that the surfaces of materials undergo radiation damage in the electron microscope similar to that observed by more conventional surface science techniques there has been substantial interest in understanding these phenomena in more detail; for a review see. For instance, surface damage in a microscope mimics damage in the space environment due to the solar wind and electron beam lithographic operations.However, purely qualitative experiments that have been done in the past are inadequate. In addition, many experiments performed in conventional microscopes may be inaccurate. What is needed is careful quantitative analysis including comparisons of the behavior in UHV versus that in a conventional microscope. In this paper we will present results of quantitative analysis which clearly demonstrate that the phenomena of importance are diffusion controlled; more detailed presentations of the data have been published elsewhere.As an illustration of the results, Figure 1 shows a plot of the shrinkage of a single, roughly spherical particle of WO3 versus time (dose) driven by oxygen desorption from the surface.

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