Pulsed Treatment Research Articles

Experimental Study on Multiscale Pore Structure Evolution and Methane Desorption Characteristics of Coal with Controlled Electrical Pulse Treatment

Experimental Study on Multiscale Pore Structure Evolution and Methane Desorption Characteristics of Coal with Controlled Electrical Pulse Treatment

Effect of Pulsed Current Treatment on Microstructure and Properties of 304 Stainless Steel Ultra-Thin Strip after Rolling

The annealing process is usually used to heat-treat cold-deformed 304 stainless steel to improve its microstructure and properties to a certain extent; however, it requires a high temperature and a long time. Because the thickness of the ultrathin strip reaches the micrometer level, it has only one or several layers of grains in the thickness direction, and the control of morphology and performance is complex. In this study, pulsed current loading was used to replace traditional annealing for treating ultrathin strips of cold-rolled 304 stainless steel. After loading a 25 W pulsed current treatment for 5 min on the cold-rolled sample, which had a thickness of 0.035 mm and width of 6 mm, complete recrystallization occurred, and the mechanical properties were significantly improved. At this point, the measured temperature was 540 °C. When annealing was used to treat the sample with the same temperature and for the same duration, the microstructure was still dominated by deformed crystals, and the mechanical properties were poor. When annealing was used to obtain a microstructure and properties similar to those obtained via 25 W electrical treatment, the required annealing temperature and time were 810 °C and 60 min, respectively. Pulsed current can increase the vacancy diffusion flux in the sample, accelerate the atomic movement, reduce the recrystallization activation energy, and make the cold-rolled 304 stainless steel ultrathin strip completely recrystallize at a lower temperature and in a shorter time. As the current power continued to increase, the recrystallized grains grew. When the pulsed current power was increased to 25 W, the recrystallized grains grew negligibly. Both recrystallization and grain growth have power thresholds. This study provides a novel approach for regulating the microstructure and mechanical properties of ultrathin cold-rolled 304 stainless steel strips.

Investigation of pulsed magnetic field treatment to enhance the properties of printed circuit board micro drill

Investigation of pulsed magnetic field treatment to enhance the properties of printed circuit board micro drill

Hollow Pt/CeO2 nanocatalysts pretreated with pulsed steam for enhanced CO oxidation performance

The supported Pt/CeO2 catalysts are widely used for the catalytic oxidation of CO at ambient conditions. Herein, we reported a new strategy for modifying the interaction between Pt and CeO2 support via pulsed steam treatment, which significantly optimized the catalytic performance of Pt/CeO2 for CO oxidation. Specifically, the hollow CeO2 nanospheres were prepared by using carbon spheres as sacrificial templates and then subjected to pulsed steam treatment at 150 °C for different times to obtain the CeO2-xH support (x means the time of pulsed steam treatment, min). It was found that the complete oxidation of CO can be achieved at 90 °C over the Pt/CeO2–50H sample, which was much lower than that (130 °C) on Pt/CeO2 without pulsed steam treatment. The XPS and in-situ DRIFTS characterizations were conducted to reveal the high performance of the Pt/CeO2–50H catalyst for CO oxidation. It was found that the valence state of Pt significantly controlled by pulsed steam treatment was critical to the catalytic activity, whereby the presence of two types of active sites (Pt0-CO and Ptδ+-CO) over Pt/CeO2–50H greatly promoted the combination of adsorbed CO and O2 to generate CO2. Accordingly, this study provides a facile method to regulate the Pt valence state by pulsed steam treatment for CeO2 support, which is critical to the CO oxidation activity.

Efficient micropropagation protocol and assessment of genetic fidelity of micropropagated plantlets of Pueraria tuberosa

The aim of this study was to develop an efficient micropropagation protocol for Pueraria tuberosa, a medicinally valuable woody liana species. The nodal explants derived from in vitro-grown seedlings were cultured on Murashige and Skoog (MS) medium containing various combinations of 6-benzylaminopurine (BAP), thidiazuron (TDZ), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA). These combinations led to the substantial development of multiple shoots. The combination of TDZ (0.57 µM/L) and IBA (0.12 µM/L) resulted in the highest regeneration rate (85%), maximum number of shoots (5.52 ± 0.67), and best shoot length (4.96 ± 0.33 cm). The most effective in vitro rooting treatment consisted of half-strength MS medium accompanied by 2.46 µM/L IBA and a 10-minute pulse treatment with the same concentration of IBA. This treatment resulted in the highest root formation (100%) and maximum roots per shoot (16.72 ± 1.81), with the highest root length (3.58 ± 0.54 cm) among all treatments tested. After four weeks under field conditions, hardened in vitro plantlets showed an 88.2% survival rate. The genetic fidelity of regenerated plants was assessed using inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) markers, which produced monomorphic bands, demonstrating the genetic homogeneity of regeneration and reliability of the in vitro propagation method.

Pulsed peritoneal dialysis in an experimental rat model: A first experience.

Peritoneal dialysis (PD) is commonly performed using either intermittent or tidal exchanges, whereas other exchange techniques such as continuous flow PD are little used. Previous research indicated that stirring the intra-peritoneal dialysate markedly increases small solute clearances. Here, we tested the hypothesis that stirring of the dialysate increases small solute clearances by using a novel exchange technique where the dialysate is pulsed back and forth during the treatment without addition of fresh fluid. PD was performed in anesthetized Sprague-Dawley rats with either no pulsations (20 mL fill volume), 2 mL (10%) pulses (21 mL fill volume), or 5 mL (25%) pulses (22.5 mL fill volume) utilizing a pulse flow rate of 5 mL/min. The higher fill volume for the pulsed treatments compensates for the fact that the average intra-peritoneal volume would otherwise be lower in pulsed treatments. Water and solute transport were closely monitored during the treatment. Net ultrafiltration decreased significantly during pulsed PD with the 25% pulse volume. The 60 min sodium dip was unaltered, whereas the fluid absorption rate was increased for the 25% group. Solute clearances did not significantly differ between groups, except for a slightly lower calcium clearance in the 25% group. Our data indicate that stirring the dialysate using pulsed exchanges does not provide any advantage compared to conventional exchange techniques. In contrast, pulsed treatments had slightly lower ultrafiltration and small solute transport. The present findings may have implications regarding the choice of tidal volume in automated PD, favoring smaller tidal volumes.

Tislelizumab-induced cytokine release syndrome: the first case report and review of the literature.

Cytokine release syndrome (CRS) is an uncommon but deadly side effect of immune checkpoint inhibitors (ICIs). ICIs are presently an increasingly important therapy option for malignant tumors, but there are limited treatments available for CRS. We present a case of a 72-year-old man who received one cycle of ICI coupled with cisplatin and albumin-binding paclitaxel therapy for a locally advanced right lung adenocarcinoma. Following an abrupt onset of dyspnea, the patient underwent a quick physical examination, blood tests and was diagnosed with CRS. After prompt initiation of glucocorticoid pulse treatment, the symptoms relieved. The case illustrates the management of severe CRS following ICI therapy while highlighting the uncommon and potentially fatal immune-related side effects.

Pulsed N2 plasma surface treatment for AlGaN/GaN HEMTs prior to PECVD SiNx passivation to reduce plasma damage

In this work, a pulse-mode N2 plasma surface treatment process was proposed as a means of reducing plasma damage and improving the GaN/GaOx ratio on the surface before SiNx deposition, which further contributes to an enhanced density of 2DEG and a reduced sheet resistance. With the pulsed N2 plasma surface treatment combined with subsequent SiNx passivation, the fabricated GaN HEMTs exhibit negligible current collapse and suppressed leakage current. The improved behavior is attributed to the fact that the pulsed N2 plasma is capable of nitriding the surface and removing carbon contaminants as identified through x-ray photoelectron spectroscopy and energy dispersive x-ray spectroscopy. Compared to the traditional continuous-wave-mode N2 plasma, the pulsed N2 plasma pre-treatment effectively prevents continuous collisions of the plasma during acceleration, thereby significantly reducing plasma damage. This work offers valuable insights for surface treatment processes in micro- and nanofabrication.

Corrosion and Discharge Behavior of As‐Rolled AZ91 Magnesium Alloy after Electro‐Pulsing Treatment

In this article, a systematic investigation into the corrosion and discharge behaviors of as‐rolled a represents aluminum, Z represents zinc, 9 and 1 represent their respective contents of 9% and 1% in the alloy (AZ91) magnesium alloy after electro pulsing treatment (EPT), considering rolling deformations of 0% (as‐cast AZ91 magnesium alloy), 20%, 30%, and 40%, is presented. In this investigation, immersion weight loss tests, electrochemical tests, and other experimental methods are employed. In the results, it is revealed that the content of the β‐Mg17Al12 phase gradually decreases with increasing rolling deformation after EPT. Notably, the highest content of β‐Mg17Al12 phase and the most outstanding corrosion resistance are achieved with as‐cast AZ91 magnesium alloy. Furthermore, at low current densities (5 and 10 mA cm−2), the 30% rolling deformation exhibits superior discharge activity, while the discharge activity of the 40% rolling deformation is most excellent at high current densities (40 and 50 mA cm−2). The microstructure observations support these findings, highlighting the close relationship between the corrosion resistance and discharge activity of as‐rolled AZ91 magnesium alloy after EPT, and the content of the β‐Mg17Al12 phase and the area of high‐energy grain boundaries.

Potential Disease-Modifying Effects of Ganglioside GM1 Pulse Treatment on Spinocerebellar Ataxia Type 3, a Parallel-Group, Double-Blind, Randomized, Controlled Trial.

Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant inherited neurodegenerative disorder for which there is currently no cure, nor effective treatment strategy. Our aim was to investigate the safety and efficacy of high-dose ganglioside GM1 (ganglioside-monosialic acid) pulse treatment in patients with SCA3. Patients were randomly allocated to receive either high-dose GM1 (400 mg on the first day followed by 200 mg/day), low-dose GM1 (40 mg/day), or placebo (normal saline) for 4 weeks. The primary outcome, assessed by measuring the change in the Scale for the Assessment and Rating of Ataxia (SARA) scores from baseline to 12 weeks post-treatment, is central to evaluating treatment efficacy. Secondary outcomesincluded changes in the International Cooperative Ataxia Rating Scale (ICARS) score, Barthel Index of Activities of Daily Living (ADL), and plasma and cerebrospinal fluid (CSF) GABA levels. Safety was assessed in all treated patients. A total of 48 patients with SCA3 were enrolled in this study. After 12 weeks, data from 43 patients were included in the efficacy analysis (intention-to-treat analysis). The least-squares mean change in the SARA score from baseline to 12 weeks post-treatment was -3.80 (standard error [SE], 0.39; 95% confidence interval [CI], -4.58 to -3.02) in the high-dose GM1 group, 0.34 (SE, 0.40; 95% CI, -0.46 to 1.13) in the low-dose GM1 group, and 0.73 (SE, 0.40; 95% CI, -0.07 to 1.52) in the placebo group, respectively. Secondary outcomes showed improvements in the ICARS score, Barthel Index of ADL, and plasma and CSF GABA levels in the high-dose GM1 group compared to the low-dose GM1 and placebo groups. All treatments were well-tolerated and safe. High-dose GM1 treatment significantly ameliorated ataxic symptoms in patients with SCA3. © 2024 International Parkinson and Movement Disorder Society.

Ecdysteroid-dependent molting in tardigrades.

Although molting is a defining feature of the most species-rich animal taxa-the Ecdysozoa, including arthropods, tardigrades, nematodes, and others1,2-its evolutionary background remains enigmatic. In pancrustaceans, such as insects and decapods, molting is regulated by the ecdysteroid (Ecd) hormone and its downstream cascade (Figure1A, see also the text).3,4,5 However, whether Ecd-dependent molting predates the emergence of the arthropods and represents an ancestral machinery in ecdysozoans remains unclear. For example, involvement of the Ecd hormone in molting regulation has been suggested only in some parasitic nematodes outside of arthropods,6,7 and insect Ecd synthesis and receptor genes are lacking in some ecysozoan lineages (FigureS1A).8,9,10 In this study, we investigated the role of Ecd in the molting process of the tardigrade Hypsibius exemplaris. We show that the endogenous Ecd level periodically increases during the molting cycle of H.exemplaris. The pulse treatment with exogenous Ecd induced molting, whereas an antagonist of the Ecd receptor suppressed the molting. Our spatial and temporal gene expression analysis revealed the putative regulatory organs and Ecd downstream cascades. We demonstrate that tardigrade molting is regulated by the Ecd hormone, supporting the ancestry of Ecd-dependent molting in panarthropods. Furthermore, we were able to identify the putative neural center of molting regulation in tardigrades. This region may be homologous to the neural center in the protocerebrum of pancrustaceans and represent an ancestral state of panarthropods. Together, our results suggest that Ecd-dependent molting evolved in the early-late Ediacaran, 22-76 million years earlier than previously suggested.11.

Ablation treatment of CFRP via nanosecond pulsed Ytterbium-doped fiber laser: Effects of process parameters on surface morphology and shear strength of adhesive bonded joints

Adhesive bonding is the joining technique that provides the maximum exploitation of Carbon Fiber Reinforced Polymers (CFRPs) for structural applications. However, it is necessary to attain a high-strength adhesive bond, achieved by removing surface contaminants, such as mold release agents, and simultaneously generating a surface structure suitable to increase the actual contact surface area. The purpose of the research work presented in this paper is to evaluate the effect of process parameters of a nanosecond pulsed laser pre-bonding surface treatment on the ablation of thermoset matrix CFRP substrates. In particular, the link between the volume of ablated material and the tensile shear strength (TSS) of adhesive bonded joints was evaluated by lap-shear tests, profilometer surveys, and Scanning Electron Microscope (SEM) analysis. ANOVA and regression models were used to highlight the influence of laser parameters, with power emerging as the most significant factor, and energy density proving pivotal for joint strength. Line spacing was also significant, while scanning direction had negligible impact. The key outcomes of the study demonstrated that controlled laser ablation plays a critical role in determining joint performance. A negative correlation was found between TSS and the thickness of ablated material, indicating that excessive ablation weakens the bond. Optimal joint strength was achieved with moderate fiber exposure while maintaining matrix integrity, emphasizing the need for precise control over laser parameters. Fracture surface analyses revealed distinct failure mechanisms, ranging from cohesive failure within the adhesive layer to interfacial failure at the fiber-matrix boundary, depending on the ablation conditions. The findings provide clear guidelines for optimizing laser surface treatments to enhance the structural performance of CFRP adhesive joints in practical applications.

Enhance forming properties of 7075-T6 aluminium alloy by two-step electromagnetic forming and electrical pulse treatment

Enhance forming properties of 7075-T6 aluminium alloy by two-step electromagnetic forming and electrical pulse treatment

A Biotechnical System for Increasing the Effectiveness of the Pre-Sowing Pulsed Laser Irradiation of Seeds to Increase Sunflower Yield

In this study, we investigated the use of the pre-sowing electrophysical stimulation of seeds, particularly focusing on optimizing technological regimes for enhancing seed quality. The aim of this study was to improve sunflower seed germination utilizing laser optical radiation. The methods explored involved the pre-sowing stimulation of oilseeds and analyzing the key mechanisms affecting germination. Through our experimental research, we sought to identify the most effective laser irradiation parameters, ensuring the maximum seed quality improvement with minimal energy use. Using seeds of the first reproduction, we employed artificial aging to simulate a reduced seed quality and determined optimal irradiation regimes. Standard methods were followed to assess seed quality before and after irradiation, with 6–7 days of further exposure. Seed germination was carried out under controlled light and temperature conditions using the “on paper” method with paper napkins. A full factorial experiment was performed and key parameters for laser irradiation were determined, confirming that the pre-sowing laser pulse treatment significantly improved seed quality. In this research, we developed a biotechnical system for processing seeds and propose a method to adjust irradiation parameters based on the initial seed quality. The system effectively enhanced germination and crop yield, offering a reliable solution for improving sunflower seed productivity through laser treatment.

Optimization of co-linear-type pulsed electric field treatment chamber for milk pasteurization

Pulsed electric fields (PEFs) are increasingly employed industrially as pasteurization methods for liquid foods. However, some issues regarding heat-sensitive, high-protein liquid foods remain unresolved. The efficacy of PEFs during continuous processing depends on the structural characteristics of the processing chamber. This study presents the optimal structure of our originally developed colinear-type PEF treatment chamber, determined through a combination of experimental and numerical calculations. Our pasteurization system, with a flow rate of 10 L/h, involved an optimized PEF treatment and a moderate heat treatment at 60 °C. Our system inactivates Listeria innocua in sterilized milk by more than seven orders of magnitude. In a durability test, the system was successfully operated continuously for more than 1 h under pasteurized conditions without any damage or component adhesion on the stainless-steel electrodes. This study provides guidelines for the high-flow pasteurization of high-protein liquid foods.

Microstructure evolution and mechanical behavior of 2024 aluminum alloy under electric pulse treatment

This study examined the effects of electric pulse treatment (EPT) on solution-treated 2024 alloy. We found that the combined effect of non-uniform stress field caused by thermal expansion and localized Joule heating promoted the formation of helical dislocations. During the subsequent aging process, these severely deformed helical dislocations formed a network configuration, which accelerated the coarsening of the S phase, and the S phase also retained a helical shape. Compared to conventional solution-treated samples, the yield strength of the EPT samples increased by 24 % with almost no loss of fracture elongation. The increase in strength is primarily due to the increase of volume fraction of rod-shaped S phase，enhancing the matrix's resistance to deformation. This study proposes a simple and rapid method to adjust dislocation configurations and aging precipitation through electric pulses, offering new insights for the industrial application of aluminum alloys to swiftly enhance mechanical properties.

Dissolution of Primary Carbides and Formation and Healing of Kirkendall Voids in Bearing Steel under Pulsed Electric Current

The alloying elements in 8Cr4Mo4V bearing steel tend to form large primary carbides with carbon, which not only causes element segregation but also becomes the primary source of fatigue crack initiation, thereby decreasing the material's usability and machinability. Owing to the excellent thermal stability of primary carbides, traditional homogenization annealing requires high temperatures, which is both time‐ and energy‐intensive. Excessively high heat treatment temperatures can also result in “overburning” of the sample. Herein, primary carbides are rapidly dissolved at low temperatures using pulsed electric current treatment. The additional free energy introduced by the pulsed electric current lowers the thermodynamic barrier for carbide dissolution. During the second‐phase dissolution process, the unbalanced diffusion of elements may cause the formation of Kirkendall voids. Due to the difference in electrical conductivity between the voids and the matrix, the pulsed electric current generates thermal compressive stress on the voids, promoting rapid atom migration to these voids and accelerating their healing. This pulse‐current treatment technology offers a novel method for the rapid dissolution of carbides in alloys at low temperatures and for the rapid healing of related voids.

Effect of pulsed light on enzyme inactivation, colour, firmness, surface morphology, and bioactive compounds in fresh and dried whole red chilies (Capsicum annuum var. longum)

The effect of pulsed light on enzymatic activity and biochemical stability of red chillies was investigated. Balancing and reducing the aw and moisture content to 0.6 aw and 0.35 aw is crucial to attain biochemical stability. Upon drying at 60 °C/5 h + 40 °C/2 h and 70 °C/11 h + 55 °C/4 h + 40 °C/2 h the enzymes inactivated to more than 30 %, respectively. Hence, to completely inactivate the enzymes, a technology has been introduced i.e., pulsed light treatment (PLT), which employed 0.53–2.59 J·cm−2. The stability of red chillies was evaluated based on the quality attributes such as enzyme activity, total phenolics, flavonoids, antioxidant capacity, ascorbic acid, capsiacinoids, and carotenoids. After treatment at fluence of 2.59 J·cm−2, there was >90 % inactivation of PPO and POD. Based on kinetic modelling, it is showed PLT better preserved the colour, texture, morphology, and bioactive compounds in 0.6 and 0.35 aw than 0.85 aw red chillies. Morphological studies determined the changes in red chillies after PLT. FTIR and GCMS analysis revealed the structural and compositional changes occurring after PLT. Therefore, drying combined with PL can be a potential alternative method to blanching along with maximizing the availability of bioactives.

Telangiectasia Macularis Multiplex Acquisita and its Potential Association with Calcium Channel Blockers: A Retrospective Study of 46 Chinese Patients.

Telangiectasia macularis multiplex acquisita is an acquired cutaneous telangiectasis of unknown aetiology, and it lacks both effective and cost-efficient treatment. This study aims to identify a novel potential associated factor of the disease and explore feasible therapeutic interventions. In this retrospective case series study, 46 Chinese patients diagnosed with telangiectasia macularis multiplex acquisita between 1 January 2007 and 18 May 2023 were included. The median age of onset was 43 years (23 to 60 years), and the male to female ratio was 10.5:1. Besides previously reported associations including chronic liver disorders, alcohol consumption, and smoking, a potential association was found between use of calcium channel blockers and development of telangiectasia macularis multiplex acquisita. Twenty-two of 27 hypertensive patients took calcium channel blockers, with 17 followed up. Ten out of 17 displayed a range of improvements following the cessation of calcium channel blockers; 1 patient reported no lesion change post-discontinuation of calcium channel blockers; 1 patient continued their medication but showed partial improvement after 2 pulsed dye laser treatments; 1 patient observed lesion colour lightening without altering hypertensive medication or other specific treatments; and another 4 kept their previous hypertensive regimen due to blood pressure stability concerns, with no change in their lesions. The study proposes that cessation of calcium channel blockers can be a novel therapeutic approach for affected individuals.

Inactivation kinetics of Bacillus cereus and Aspergillus niger spores in dehydrated onion shreds after pulsed light and infrared treatments

Fresh onions are dehydrated to increase their shelf-life. Primarily, open dehydration techniques like solar dehydration come with the problem of contamination through natural air convection. A solar conduction dryer that uses conduction, convection, and radiation for dehydration of food samples is exploited in this study. The food samples are often contaminated by Bacillus and Aspergillus species spores. As a remedy, pulsed light treatment as a non-thermal technology and infrared treatment as a thermal technology are studied and compared. Bacillus cereus and Aspergillus niger spores are chosen as a representative of bacterial and fungal contamination in onions. Dehydrated onion shreds with varying water activities (0.4, 0.5, 0.6) were treated. The spore inactivation was best described by Weibull model as compared with first-order model. Scanning electron microscopy images of the microbial cells showed surface distortions on the bacterial and fungal spores. The effect of the treatment technologies on the colour, flavour (thiosulphinate and pyruvic acid concentration), total phenolic and flavonoid content, and ascorbic acid concentration are compared. Overall, pulsed light treatment showed promising inactivation with a maximum log reduction of 4.5 log B. cereus spores·g−1 and 3.1 log A. niger spores·g−1 at 2.131 J·cm−2 in samples with water activity 0.6. The inactivation rate increased with an increase in water activity. The colour was better retained in pulsed light treated samples. The thiosulphinate content (9.24 μmol·g−1), total phenolics (0.268 mg GAE·g−1), and flavonoid content (0.344 mg QE·g−1) in the sample were improved upon pulsed light exposure.Graphical