Signal-to-noise analysis of biomedical photoacoustic measurements in time and frequency domains

Sensitivity analysis of photoacoustic measurements is conducted using estimates of the signal-to-noise ratio (SNR) achieved under two different modes of optical excitation. The standard pulsed time-domain photoacoustic imaging is compared to the frequency-domain counterpart with a modulated optical source. The feasibility of high-SNR continuous wave depth-resolved photoacoustics with frequency-swept (chirp) modulation pattern has been demonstrated. Utilization of chirped modulation waveforms achieves dramatic SNR increase of the periodic signals and preserves axial resolution comparable to the time-domain method. Estimates of the signal-to-noise ratio were obtained using typical parameters of piezoelectric transducers and optical properties of tissue.     

Ptychographic characterization of the wavefield in the focus of reflective hard X-ray optics

A technique for quantitatively characterizing the complex-valued focal wavefield of arbitrary optics is described and applied to reconstructing the coherent focused beam produced by a reflective/diffractive hard X-ray mirror. This phase-retrieval method, based on ptychography, represents an important advance in X-ray optics characterization because the information obtained and potential resolution far exceeds that accessible to methods of directly probing the focus. Ptychography will therefore be well-suited for characterizing and aligning future nanofocusing X-ray optics.     

Pulsed magnetic field excitation sensitivity of match-type electric blasting caps

This paper presents a study on energy deposition and electromagnetic compatibility of match-type electroexplosive devices (EEDs), which recently have found more usage in pulsed power environments with high electromagnetic interference (EMI) background. The sensitivity of these devices makes them dangerous to intended and unintended radiation produced by devices commonly used in pulsed power environments. Match-type EEDs have been found to be susceptible to such low levels of energy (7-8 mJ) that safe operation of these EEDs is vital when in use near devices that produce high levels of pulsed EMI. The scope of this paper is to provide an investigation that incorporates results of similar studies to provide detonation characteristics of these EEDs. The three topics included in this study are sensitivity testing, modeling of the thermodynamic heat propagation, and electromagnetic compatibility from pulsed electromagnetic radiation. The thermodynamic joule heating of the primary explosive has been modeled by a solution to the 1D heat equation. A simple pulsed generator, Marx generator with an inductive load, was used for the electromagnetic compatibility assessment of the coupled field between the pulse generator and shorted EED. The results of the electromagnetic compatibility assessment relate the resistive, inductive, and capacitive components of the pulse generator to the area of the shorted EED.     

Electrochemical characteristics of semi conductive silicon anode for lithium polymer batteries

In this paper, the electrochemical characteristics of semi conductive silicon thin films (n-type and p-type silicon) anodes integrated with the solid polymer electrolyte for lithium polymer batteries were investigated. The charge/discharge cycling tests revealed that the phosphorus-doped n-type silicon electrode shows the most stable cyclic performance after the 40^th cycle and still maintains a reversible specific capacity of about 2,500 mAh/g. The enhanced electrochemical performance of the doped silicon anode was attributed to the enhancement of its electrical conductivity, which was further confirmed by impedance spectroscopy and surface analysis by XPS.     

Forward and Reverse Converters and Moduli Set Selection in Signed-Digit?Residue?Number?Systems

This paper presents an investigation into using a combination of two alternative digital number representations; the residue number system (RNS) and the signed-digit (SD) number representation in digital arithmetic circuits. The combined number system is called RNS/SD for short. Since the performance of RNS/SD arithmetic circuits depends on the choice of the moduli set (a set of pairwise prime numbers), the purpose of this work is to compare RNS/SD number systems based on different sets. Five specific moduli sets of different lengths are selected. Moduli-set-specific forward and reverse RNS/SD converters are introduced for each of these sets. A generic conversion technique for moduli sets consisting of any number of elements is also presented. Finite impulse response (FIR) filters are used as reference designs in order to evaluate the performance of RNS/SD processing. The designs are evaluated with respect to delay and circuit area in a commercial 0.13 μm CMOS process. For the case of FIR filters it is shown that generic moduli sets with five or six moduli results in designs with the best area × delay products.

离子注入后品圆清洗带来的材料和掺杂剂损失的测量

对45nm及以下技术节点的逻辑器件嗣造来说,经过次数不断增加的高剂量离子注入光阻层的清洗步骤后,仍保持超浅结（USJ）的完整性非常重要。在PMOS区采用SiGe带来了材料方面的又—挑战。一种新型短循环法可精确测量各种去胶储洗工艺造成的非晶硅或SiGe的损失量。     

Chemically and enzymatically catalyzed synthesis of C6–C10 alkyl benzoates

The esterification of benzoic acid with n‐hexanol, n‐octanol, 2‐ethyl hexanol and n‐decanol was investigated in detail. An analysis of the reaction kinetics of esterification in the presence of different commercially available chemical catalysts was carried out. The effects of catalyst type and loading on the reaction rate were studied. Although the considered reaction is bimolecular, it showed a first‐order behavior, and a linear dependence with respect to the catalyst concentration was observed. Hence, a new approach is presented to describe the reaction kinetics accurately over a wide range. The application of biotechnological synthesis applying different enzymes as catalysts offers an interesting alternative besides chemical synthesis. Especially an esterase from Bacillus subtilis immobilized on Sepabeads EC‐EP showed high stability and was applied for 2 days in the synthesis of hexyl benzoate. Nevertheless, the chemical reaction route remains superior with respect to the catalyst activities under the applied conditions, which were 25 kU/g for the chemical reaction and 0.7 kU/g for the best enzymatic conversion.