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All solid-state microchip lasers having the advantage of short cavity lengths give them tremendous potential as pulsed devices for short pulse laser generation. In this work, by constructing a compact microchip-like laser resonator, we have demonstrated continuous-wave (CW) Pr,Mg:SrAl12O19 (SRA) lasers at 622 nm and 643 nm, respectively with maximum output powers of 0.69 W and 1.18 W with excellent beam qualities, which is believed to be the highest powers that have achieved in Pr3+ microchip lasers. Based on this CW opeation, we, by using a Co:LMA saturabel absorber, have further demonstrated passively Q-switched operation of the two lasers. The shortest pulse widths reached about 28.5 ns (for the 622 nm laser) and 31.9 ns (for the 643 nm laser), which are relatively short pulse time durations for passively Q-switched Pr3+ lasers thanks to the compact laser configuration. This work has proposed a simple route for achieving compact high-power CW and short-pulse Q-switched visible lasers.

In this article, the self-heating effect (SHE) of both dc and ac for a three-channel nanowire-field effect transistor (FET) is investigated and analyzed. In the dc mode, as $\Delta {T}_{{\text {max}}}$ (definition: ${T}_{{\text {max}}}-{300}$ K) increases to 65 K, the transistor suffers from an ${I}_{{\text {on}}}$ degradation of 3.8% along with a ${R}_{{\text {th}}}$ of 4.875 [K/ $\mu \text{W}$ ]. In the ac mode, as the heating time (same as the pulse time) increases, the heat is accumulated more and the cooling time increases accordingly. It is confirmed that $\Delta {T}_{{\text {max}}}$ decreases as the device operating frequency increases and $\Delta {T}_{{\text {max}}}$ saturates to about 40 K at 4 GHz. Finally, the thermal characteristics and the lifetime are analyzed while changing the duty cycle to 25%, 50%, and 75%. It shows that $\Delta {T}_{{\text {max}}}$ increases to 38, 42, and 45 K, respectively, and HCI and BTI lifetime can be increased up to two times and three times, respectively.

The objective of this study was to experimentally evaluate the influence of particle deposition on gas filtration with pulse jet cleaning. Filtration experiments were performed using dolomitic limestone particles, with polyester and polypropylene filter media. A total of 100 filtration tests were performed with a surface velocity of 4 cm/s. The stipulated maximum pressure drop was 1000 Pa, the pulse time was 200 ms, and the pulse pressure was 200 kPa. After 100 filtration cycles, the polyester filter presented higher cleaning efficiency, higher collection efficiency, lower particle retention, higher permeability, lower residual pressure drop, and lower mass retained after reverse air pulse cleaning, compared to the polypropylene filter. The results confirmed that the polyester filter presented excellent operational performance when pulse jet cleaning was used. Furthermore, surface filtration was more pronounced for the polyester filter, due to lower deposition of particles inside the filter.

The objective of this study is to characterize the potential damage of near-fault ground motions on reinforced concrete bridge piers, providing information for engineering practice. To achieve this objective, 200 real near-fault pulse-type records and a bridge pier were selected. The same number of real far-fault ground motions was also selected for comparison. Inelastic time history and damage analyses were performed for the pier subjected to the selected near-fault and far-fault ground motions. The obtained results showed that more than 91% near-fault motions caused the pier to collapse while the pier survived under almost all far-fault motions. The responses of the pier under near-fault motions were characterized by one or few large hysteretic cycles. The damage indices of the pier subjected to near-fault ground motions increased rapidly when the pier underwent pulses of near-fault motions, and the pier damage was mainly caused by pulses. Collapse of the pier subjected to near-fault motions occurred at the pulse time. The duration to collapse, which was defined as the duration from light damage to collapse, of the pier under near-fault motions was extremely short (approximately 2.3–2.5 s). These special and negative structural damage characteristics of near-fault ground motions should be considered in designing and mitigating seismic hazards for structures located in near-fault regions.

The present study aimed to determine the optimum levels of experimental factors that affect electroplating performance, i.e., filling via holes without defects. To this end, the Taguchi experimental design method was employed. The uniformity of plated Cu thickness was selected as the characteristic, and experimental conditions were determined using an orthogonal matrix array with respect to the selected experimental factors. The results were analyzed based on the signal-to-noise ratios acquired from experimental measurements. When the aspect ratio was low, the concentration of a leveler was found to be the determining factor. As the aspect ratio increased, the effect of current density and pulse time became more significant.

SnO2-x thin films with different concentration oxygen vacancies were prepared by Atomic Layer Deposition (ALD). Specifically, the oxygen vacancy concentration was controlled by the oxidation pulse time during the ALD process. The crystal structure of the as-prepared thin films was determined by XRD, and the magnetic properties were measured by VSM, while the optical properties were measured by optical transmittance spectrum. The results showed that the oxygen vacancy concentration of the SnO2-x could be controlled by the oxidation pulse time, and the crystal structures, magnetic properties, and optical properties were largely impacted by the concentration of oxygen vacancy.

An 8-tap CMOS lock-in pixel image sensor that has seven carrier-capturing and a draining time window was developed for short-pulse time-of-flight (TOF) measurements. The proposed pixel for the short-pulse TOF measurements has seven consecutive time-gating windows, each of which has the width of 6 ns, which is advantageous for high-resolution range imaging, particularly for relatively longer distances (&gt, 5 m) and under high ambient light operations. In order to enhance the depth resolution, a technique for the depth-adaptive time-gating-number assignment (DATA) for the short-pulse TOF measurement is proposed. A prototype of the 8-tap CMOS lock-in pixel image sensor is implemented with a 1POLY 4METAL 0.11-&mu, m CIS process. The maximum non-linearity error of 1.56%FS for the range of 1&ndash, 6.4 m and the depth resolution of 6.4 mm was obtained at 6.2 m using the DATA technique.

Liquid crystal elastomer (LCE) fibers are capable of large and reversible deformations, making them an ideal artificial muscle. However, limited to stimulating source and structural design, current LCE fibers have not yet achieved both large contraction ratio and fast contraction rate to perform the intense motion. In this work, electrothermal-responsive liquid metal (LM) containing LCE (LM-LCE) fibers is reported. By introducing flexible liquid metal, LM-LCE fibers retain deformability with a large contraction ratio similar to that of pure LCE fibers and are endowed with electrical responsiveness. Applying precisely controlled electrical stimulation, the contraction ratio and rate of LM-LCE fibers can be programmed by adjusting voltage value and pulse time. Under electrical stimulation at 1.25 V cm-1 , 0.1 s, LM-LCE fibers can produce over 40% contraction ratio at an ultrafast contraction rate of up to 280% s-1 . Furthermore, LM-LCE fibers mimic human triceps muscle and can conduct precise ball shooting. LM-LCE fibers with excellent contraction ratio and rate extend their functionality as artificial muscles to perform intense movements and are expected to enrich the challenging applications of soft robots.

The differential pulse adsorptive cathodic stripping voltammetry (DP-AdsCSV) employing the hanging mercury drop electrode (HMDE) was used towards the determination of two psychotropic drugs in environmental samples. Voltammetric and experimental conditions to Clonazepam (CLO) and diazepam (DIAZ) were optimized and the methods were in-house validated. Accumulation potentials were −0.3 V to CLO and −0.6 V to DIAZ at 120 s of accumulation time. Pulse amplitude, pulse time and scan rate were 80 mV, 20 ms and 25 mV s−1 to CLO and 100 mV, 20 ms and 40 mV s−1 to DIAZ, respectively. Recovery tests were done in three different concentrations to evaluate methods’ accuracy and the results were from 88±6 to 120±13 %. In precision tests, standard deviations were lower than 15 % for both methods. Goods limits of quantification 0.65 and 0.27 μg L−1 to CLO and DIAZ respectively were achieved without pre-concentration steps such as SPE, etc. Voltammetry employing HMDE was first used for the determination of CLO and DIAZ in natural water. Natural samples were spiked and recovery tests confirmed the applicability of the methods developed. Nine samples from Parana state, Brazil, were analyzed and CLO and DIAZ values were below the limits of detection in all samples.

This work investigates the effects of varying reverse pulse time (0 s, 0.5 s, 1 s, 2.5 s, and 5 s) and varying the forward current densities (20 mA/cm2, 40 mA/cm2 and 60 mA/cm2) on the surface structure, composition, hardness and corrosion resistance of Ni-W coatings deposited by the pulse reverse current (PRC) electrodeposition method. It was observed that the reverse pulse current time and the forward current density a parabolic affect the corrosion resistance of the Ni-W coatings. The optimum reverse pulse time and forward current density for the set of parameters used in the experiments was determined to be 1 s and 40 mA/cm2.

It is widely known that pulsed magnetic field (PMF) is very useful tool to manipulate chemical and physiological processes in human body. The purpose of our study is to observe dynamics of rouleaux patterns of red blood cells (RBC) under PMF. The aggregation of RBCs or rouleaux formation is caused by fibrinogen in blood plasma. The maximum magnetic field intensity is 0.27 T and pulse time of 0.102 msec and pulse repetition rate was 1 ㎐. PMF stimulus was applied to the palm of left hand for 5, 10, 15 and 20 min. Live blood analysis was used in vitro in order to quantitatively estimate the velocity of RBC exposed to PMF stimulus. The velocity of stacked-RBC of 10 minute PMF stimulus was increased up to 8 × 10 −4 m/sec, but it decreased rapidly as the time passed. The results of present study have adduced that PMF stimulus on hand provide the improvement of RBC rouleaux formation, increase of RBC’s moving velocity as well as low blood viscosity.

This work was performed in order to evaluate the operating conditions during the pulse jet cleaning filtration using different surface treated fibrous filters. The experiments were realized using a small flat media. The comparative studies were performed with untreated and treated (singeing/calendering and calendering/thermofixation with an eggshell type anti-pilling finish (smooth surface) on one side) polyester filters to remove micrometric particles of dolomitic limestone. Filtration tests were conducted with a superficial velocity of 4 cm/s. The stipulated maximum pressure drop was 100 Pa, the pulse time was 200 ms and pressure pulse (Pp) of 2 kgf/cm2. The filters showed satisfactory performance during fifty cycles. The untreated filter presented better cleaning efficiency and lower residual pressure drop, resulting in better regeneration of the filter during fifty cycles. However, the collection efficiency of the untreated filter was lower, compared to the surface-treated filters. The findings indicate that it is important to use surface treatment of filters in order to avoid deep deposition of particles and achieve high collection efficiencies during prolonged filtration cycles.