Kinetic Measurements of Singlet Oxygen Phosphorescence in Hydrogen-Free Solvents by Time-Resolved Photon Counting

Abstract Dynamic hot-electron emission using time-resolved photon counting can address the long-term failure analysis and debug requirements of the semiconductor industry's advanced devices. This article identifies the detector performance parameters and components that are required to scale and keep pace with the industry's requirements. It addresses the scalability of dynamic emission with the semiconductor advanced device roadmap. It is important to understand the limitations to determining that a switching event has occurred. The article explains the criteria for event detection, which is suitable for tracking signal propagation and looking for logic or other faults in which timing is not critical. It discusses conditions for event timing, whose goal is to determine accurately when a switching event has occurred, usually for speed path analysis. One of the uses of a dynamic emission system is to identify faults by studying the emission as a general function of time.

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Single Point PICA Probing with an Avalanche Photo-Diode

ISTFA 2001: Conference Proceedings from the 27th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2001p0023 ◽

2001 ◽

Author(s):

Mike Bruce ◽

Rama R. Goruganthu ◽

Shawn McBride ◽

David Bethke ◽

J.M. Chin

Keyword(s):

Single Photon ◽

Single Point ◽

Photon Counting ◽

Ring Oscillator ◽

Time Resolved ◽

Single Photon Counting ◽

Photo Diode ◽

Avalanche Photo Diode ◽

Photo Multiplier Tube ◽

Channel Plate

Abstract For time resolved hot carrier emission from the backside, an alternate approach is demonstrated termed single point PICA. The single point approach records time resolved emission from an individual transistor using time-correlated-single-photon counting and an avalanche photo-diode. The avalanche photo-diode has a much higher quantum efficiency than micro-channel plate photo-multiplier tube based imaging cameras typically used in earlier approaches. The basic system is described and demonstrated from the backside on a ring oscillator circuit.

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Helmet Phthalocyaninato Iron Complex as a Primary Drier for Alkyd Paints

Materials ◽

10.3390/ma14051220 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1220

Author(s):

Jan Honzíček ◽

Eliška Matušková ◽

Štěpán Voneš ◽

Jaromír Vinklárek

Keyword(s):

Catalytic Performance ◽

Mechanical Tests ◽

Iron Complex ◽

Kinetic Measurements ◽

Time Resolved ◽

Strong Activity ◽

Vis Spectroscopy ◽

Order Of Magnitude ◽

Transparent Coatings ◽

Time Resolved Infrared Spectroscopy

This study describes the catalytic performance of an iron(III) complex bearing a phthalocyaninato-like ligand in two solvent-borne and two high-solid alkyd binders. Standardized mechanical tests revealed strong activity, which appeared in particular cases at concentrations about one order of magnitude lower than in the case of cobalt(II) 2-ethylhexanoate, widespread used in paint-producing industry. The effect of the iron(III) compound on autoxidation process, responsible for alkyd curing, was quantified by kinetic measurements by time-resolved infrared spectroscopy and compared with several primary driers. Effect of the drier concentration on coloration of transparent coatings was determined by UV–Vis spectroscopy.

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Photophysical Properties of Protoporphyrin IX, Pyropheophorbide-a, and Photofrin® in Different Conditions

Pharmaceuticals ◽

10.3390/ph14020138 ◽

2021 ◽

Vol 14 (2) ◽

pp. 138

Author(s):

Bauyrzhan Myrzakhmetov ◽

Philippe Arnoux ◽

Serge Mordon ◽

Samir Acherar ◽

Irina Tsoy ◽

...

Keyword(s):

Singlet Oxygen ◽

Photophysical Properties ◽

Protoporphyrin Ix ◽

Fluorescence Emission ◽

Solvent Polarity ◽

Visible Absorption ◽

Light Dosimetry ◽

Time Resolved ◽

Pyropheophorbide A ◽

Influence Of Solvent

Photodynamic therapy (PDT) is an innovative treatment of malignant or diseased tissues. The effectiveness of PDT depends on light dosimetry, oxygen availability, and properties of the photosensitizer (PS). Depending on the medium, photophysical properties of the PS can change leading to increase or decrease in fluorescence emission and formation of reactive oxygen species (ROS) especially singlet oxygen (1O2). In this study, the influence of solvent polarity, viscosity, concentration, temperature, and pH medium on the photophysical properties of protoporphyrin IX, pyropheophorbide-a, and Photofrin® were investigated by UV-visible absorption, fluorescence emission, singlet oxygen emission, and time-resolved fluorescence spectroscopies.

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Photoreactivity of Hair Melanin from Different Skin Phototypes—Contribution of Melanin Subunits to the Pigments Photoreactive Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22094465 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4465

Author(s):

Krystian Mokrzynski ◽

Shosuke Ito ◽

Kazumasa Wakamatsu ◽

Theodore G. Camenish ◽

Tadeusz Sarna ◽

...

Keyword(s):

Chemical Composition ◽

Singlet Oxygen ◽

Near Infrared ◽

Paramagnetic Resonance ◽

Time Resolved ◽

W Band ◽

Epr Oximetry ◽

X Band ◽

Hair Samples ◽

Electron Paramagnetic

Photoreactivity of melanin has become a major focus of research due to the postulated involvement of the pigment in UVA-induced melanoma. However, most of the hitherto studies were carried out using synthetic melanin models. Thus, photoreactivity of natural melanins is yet to be systematically analyzed. Here, we examined the photoreactive properties of natural melanins isolated from hair samples obtained from donors of different skin phototypes (I, II, III, and V). X-band and W-band electron paramagnetic resonance (EPR) spectroscopy was used to examine the paramagnetic properties of the pigments. Alkaline hydrogen peroxide degradation and hydroiodic acid hydrolysis were used to determine the chemical composition of the melanins. EPR oximetry and spin trapping were used to examine the oxygen photoconsumption and photo-induced formation of superoxide anion, and time-resolved near infrared phosphorescence was employed to determine the singlet oxygen photogeneration by the melanins. The efficiency of superoxide and singlet oxygen photogeneration was related to the chemical composition of the studied melanins. Melanins from blond and chestnut hair (phototypes II and III) exhibited highest photoreactivity of all examined pigments. Moreover, melanins of these phototypes showed highest quantum efficiency of singlet oxygen photogeneration at 332 nm and 365 nm supporting the postulate of the pigment contribution in UVA-induced melanoma.

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Simple scanning near-infrared time-correlated single-photon counting instrument with a pulsed diode laser and avalanche photodiode (APD) for time-resolved measurements in scanning applications with a DNA sequencer

10.1117/12.347539 ◽

1999 ◽

Cited By ~ 2

Author(s):

Yuling Zhang ◽

Steven A. Soper ◽

Lyle R. Middendorf ◽

John A. Wrum ◽

Rainer Erdmann ◽

...

Keyword(s):

Diode Laser ◽

Near Infrared ◽

Single Photon ◽

Photon Counting ◽

Avalanche Photodiode ◽

Time Resolved ◽

Single Photon Counting ◽

Time Resolved Measurements ◽

Dna Sequencer

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Detector commissioning and development for PETRA-III

Diamond Light Source Proceedings ◽

10.1017/s2044820110000043 ◽

2010 ◽

Vol 1 (SRMS-7) ◽

Cited By ~ 1

Author(s):

David Pennicard ◽

Heinz Graafsma ◽

Michael Lohmann

Keyword(s):

High Speed ◽

Materials Science ◽

Dynamic Range ◽

Photon Counting ◽

High Energy ◽

X Rays ◽

Silicon Detectors ◽

Time Resolved ◽

Wide Range ◽

Synchrotron Light

The new synchrotron light source PETRA-III produced its first beam last year. The extremely high brilliance of PETRA-III and the large energy range of many of its beamlines make it useful for a wide range of experiments, particularly in materials science. The detectors at PETRA-III will need to meet several requirements, such as operation across a wide dynamic range, high-speed readout and good quantum efficiency even at high photon energies. PETRA-III beamlines with lower photon energies will typically be equipped with photon-counting silicon detectors for two-dimensional detection and silicon drift detectors for spectroscopy and higher-energy beamlines will use scintillators coupled to cameras or photomultiplier tubes. Longer-term developments include ‘high-Z’ semiconductors for detecting high-energy X-rays, photon-counting readout chips with smaller pixels and higher frame rates and pixellated avalanche photodiodes for time-resolved experiments.

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