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The defects in the 20 inch PMTs’ glass shell is very harmful for the stress distribution of the whole body and reduce the its lifetime. In this paper, we develop a digital image processing for the detection of 20 inch PMTs’ glass shell, which can detect defects in hollow ellipsoid surface of the PMTs’ glass shell with large aperture. The theory and the final system is showed in this paper, we use a telecentric system with a fixed working distance, a special cylindrical long optic illuminator is placed in the center position of the glass shell, and illuminate the detected surface with uniform intensity light. The image system is placed in a specially made elliptical guideway with the same shape of the glass shell, which is suitable for digital image processing. Finally, by the process of classification and statistics of surface defects ,we can get the result, the defects of the 20 inch PMTs’ glass shell can be examined with a resolution of micron, and the discrimination, classification, accuracy and the detection speed can meet the required indicators.

Interfacial characterization, which includes wettability, interfacial microstructure and interfacial thermodynamics between VN substrate and Ti–Al molten alloy with different Al concentrations, was studied by the sessile drop method at 1758 K. The wettability between molten Ti–Al alloy and VN depends on alloy composition. The initial apparent contact angle increases from 95 to 120° with increasing Al content from 40 to 80 wt.% in the Ti–Al alloys. The Ti–Al/VN system is a typical dissolution system. The effect of dissolution on the apparent contact angle is reflected in the initial stage and progresses synchronously with movement of the triple-phase line. The wettability of Ti–Al/VN system shows no remarkable improvement with the dissolution of V. AlN and TiN should be formed as the interfacial reaction products during dissolution reaction of VN substrate.

Hereditary hemochromatosis (HH) is an inherited iron overload disorder characterized by normal iron-driven erythropoiesis and abnormal iron metabolism, leading to excess iron deposited in parenchymal cells of liver, heart, and endocrine glands. Iron hormone, hepcidin, plays a critical role in iron homeostasis through interaction with ferroportin (FPN), a major cellular iron exporter. Hepcidin is encoded by hepcidin antimicrobial peptide (HAMP). Mutations in hepcidin and any genes that regulate the biology of hepcidin, including hemochromatosis genes (HFE), Hemojuvelin (HJV), transferring receptor 2 (TFR2) and FPN, result in hemochromatosis. The identification of hepcidin and its role will provide a better understanding for pathogenesis of HH.

The partial isothermal section of the phase diagram of the Nd–Al–Si ternary system at 500°C (50 at.% Nd or less) has been investigated by X-ray diffraction analysis, differential thermal analysis, scanning electron microscopy and electron micro-probe analysis. The existence of six binary compounds, αNd 2 Si 3 , βNdSi x ( x ⩽1.8⩽2.0), NdAl, NdAl 2 , NdAl 3 and αNd 3 Al 11 , and three ternary compounds, NdAl 2 Si 2 ( γ ), NdAl 1.75 Si 0.25 ( δ ), NdAl 1.25 Si 0.25 ( η ), was confirmed. The ternary compound NdAl 1.5 Si 0.5 was not found in this section. This isothermal section consists of 11 single-phase regions, 21 two-phase regions and 11 three-phase regions. The compound NdAl 1.25 Si 0.25 has a large homogeneity range, while the other ternary compounds are non-solubility compounds.

The isothermal section of the phase diagram of the Gd–Mn–Ni ternary system was investigated by X-ray powder diffraction, optical microanalysis and electron probe microanalysis techniques. It consists of 14 single-phase regions, 26 two-phase regions and 13 three-phase regions. At 803 K, the maximum solid solubility of Mn in Ni, Gd 2 Ni 17 , GdNi 5 , Gd 2 Ni 7 , GdNi 3 , GdNi 2 , GdNi and Gd 3 Ni is about 31, 18, 13, 10, 8, 8, 4 and 2 at%, respectively. The maximum solid solubility of Ni in Mn, GdMn 12 , Gd 6 Mn 23 and GdMn 2 is about 3, 4, 3 and 5 at%, respectively. The binary compounds GdNi 4 and Gd 3 Ni 2 were not observed.

This thesis presents the design and implementation of PMOS-based integrated charge pumps with extended voltage range and their regulation circuits in a standard process. The performance of charge pumps are evaluated by their output resistances and power conversion efficiencies. Formulas which describe the charge pump characteristics are developed and presented. Existing charge pumps are analyzed and studied to understand their limitations in generating high voltages and achieving high performance. The proposed charge pump structures are designed to use PMOS switches to alleviate the high voltage stresses across transistors by biasing their bulk independently. The voltages across transistors and capacitors are kept within the suggested voltage rating (VDD)regardless of how high the output voltage is, thus the maximum voltage range is extended and no longer limited by the breakdown voltages of the devices. The charge pump circuits only need low-voltage devices and standard processes, and can be easily integrated in a digital or mixed-signal design. The proposed charge pump regulation circuits include a voltage divider, a voltage controlled ring oscillator and a feedback operational amplifier. The regulation circuits are able to adjust the clock frequency to regulate the charge pump to a steady output voltage (set by the reference voltage) under a large range of current loads. A test chip including the proposed charge pumps and regulation circuits was fabricated in a 0.18 um digital CMOS process provided by Taiwan Semiconductor Manufacturing Company (TSMC). The proposed charge pumps were tested and demonstrated the reliable generation of output voltages up to 11.47 V using only low-voltage devices. The simulation and measurement results have been presented and compared, demonstrating the functionality and performance of the proposed circuits. Kapik Integration, Mitacs

The isothermal section of the phase diagram of the ternary system Co–Pr–Si at 500°C (60 at.% Pr or less) was investigated by X-ray diffraction, optical microscopy and electron microscopy techniques. The section consists of 22 single-phase regions, 48 two-phase regions and 27 three-phase regions. There exist five limit solid solutions in this system. The intermetallic compound CoPrSi 2 is a new phase found in this work.

The isothermal section of the phase diagram of the ternary system Co–Pr–Si at 500°C (60 at.% Pr or less) was investigated by X-ray diffraction, optical microscopy and electron microscopy techniques. The section consists of 22 single-phase regions, 48 two-phase regions and 27 three-phase regions. There exist five limit solid solutions in this system. The intermetallic compound CoPrSi 2 is a new phase found in this work.

The isothermal section of the phase diagram of the Nd–Ni–Ti ternary system at 773 K has been investigated by X-ray powder diffraction, DTA, optic microscopy and scanning electron microscopy techniques. It consists of 13 single-phase regions, 23 two-phase regions and 11 three-phase regions. At 773 K, the maximum solid solubilities of Ti in Ni, NdNi 5 , Nd 2 Ni 7 , NdNi 3 and NdNi 2 are about 7, 3, 3, 3 and 2 at.% Ti, respectively. The existence of any ternary compounds was not observed.