Single Process Research Articles

High-precision measurement of the complex magneto-optical Kerr effect using weak measurement

The present paper introduces a quantum weak measurement (WM) scheme for the measurement of the complex magneto-optical Kerr effect (MOKE). We achieve the simultaneous measurement of the Kerr rotation angle and the ellipticity in a single WM process by utilizing two auxiliary pointers derived from the same meter state. The experimental measurement precision for both the Kerr rotation angle and the ellipticity is capable of reaching 10−4 deg. This technique is also employed for the determination of the complex magneto-optical constant Q. The proposed method overcomes the limitation of acquiring the complex magneto-optical Kerr parameters through a multi-step measurement process, which was previously encountered. This breakthrough holds immense significance for efficiently measuring and applying the complex MOKE with high precision and cost-effectiveness.

In Vitro and In Vivo testing of 3D-Printed Amorphous Lopinavir Printlets by SelectiveLaser Sinitering: Improved Bioavailability of a Poorly Soluble Drug.

The aim of this paper was to investigate the effects of formulation parameters on the physicochemical and pharmacokinetic (PK) behavior of amorphous printlets of lopinavir (LPV) manufactured by selective laser sintering 3D printing method (SLS). The formulation variables investigated were disintegrants (magnesium aluminum silicate at 5-10%, microcrystalline cellulose at 10-20%) and the polymer (Kollicoat® IR at 42-57%), while keeping printing parameters constant. Differential scanning calorimetry, X-ray powder diffraction, and Fourier-transform infrared analysis confirmed the transformation of the crystalline drug into an amorphous form. A direct correlation was found between the disintegrant concentration and dissolution. The dissolved drug ranged from 71.1 ± 5.7% to 99.3 ± 2.7% within 120min. A comparative PK study in rabbits showed significant differences in the rate and extent of absorption between printlets and compressed tablets. The values for Tmax, Cmax, and AUC were 4 times faster, and 2.5 and 1.7 times higher in the printlets compared to the compressed tablets, respectively. In conclusion, the SLS printing method can be used to create an amorphous delivery system through a single continuous process.

Development of fiber-reinforced polylactic acid filaments using untreated/silane-treated trichosanthes cucumerina fibers for additive manufacturing

Multi-material additive manufacturing is gaining importance due to the enhancement of properties by utilizing different materials in a single additive process, especially in 3D printing. The prime motive is the need for eco-friendly materials, with the waste-to-wealth concept being the current global trend. Trichosanthes Cucumerina stem fiber, which is obtained from the discarded stem of Trichosanthes Cucumerina plant, is used in this work; the treatment of the Trichosanthes Cucumerina fibers was done using silane. Six filaments were developed with varying untreated/silane-treated Trichosanthes Cucumerina contents (3, 6, and 9%) compared with pure PLA filaments for 3D printing. Developed filaments were assessed for ultimate tensile strength, diameter variation, differential scanning calorimetry, water absorption, morphological and surface roughness. The test results elucidated that the 6% silane-treated Trichosanthes Cucumerina fiber-reinforced/PLA filament had the highest tensile strength of 63.5 MPa with better fiber distribution. The 3% silane-treated Trichosanthes Cucumerina fiber-reinforced/PLA filament had the least diameter deviation of 0.0015 mm. Based on the test data, the 6% silane-treated Trichosanthes Cucumerina fiber-reinforced/PLA filament can be utilized to prepare biodegradable components.

Linking intrinsic scales of ecological processes to characteristic scales of biodiversity and functioning patterns

Ecology is a science of scale, which guides our description of both ecological processes and patterns, but we lack a systematic understanding of how process scale and pattern scale are connected. Recent calls for synthesis between population ecology, community ecology, and ecosystem ecology motivate the integration of phenomena at multiple organizational levels. Furthermore, many studies leave out the scaling of a critical process: species interactions, which may be non‐local through movement or foraging and must be distinguished from dispersal scales. Here, we use simulations to explore the consequences of three different process scales (species interactions, dispersal, and the environment) on emergent patterns of biodiversity, ecosystem functioning, and their relationship, in a spatially‐explicit landscape and stable equilibrium setting. A major result of our study is that the spatial scales of dispersal and species interactions have opposite effects: a larger dispersal scale homogenizes spatial biomass patterns, while a larger interaction scale amplifies their heterogeneity. Interestingly, the specific scale at which dispersal and interaction scales begin to influence landscape patterns depends on the scale of environmental heterogeneity – in other words, the scale of one process allows important scales to emerge in other processes. This interplay between process scales, i.e. a situation where no single process dominates, can only occur when the environment is heterogeneous and the scale of dispersal small. Finally, contrary to our expectations, we observe that the spatial scale of ecological processes is more clearly reflected in landscape patterns (i.e. distribution of local outcomes) than in global patterns such as species–area relationships (SARs) or large‐scale biodiversity–functioning relationships. Overall we conclude that long‐range interactions often act differently and even in opposite ways to dispersal, and that the landscape patterns that emerge from the interplay of long‐ranged interactions, dispersal and environmental heterogeneity are not well captured by often‐used metrics like the SAR.

Development of a three-stage process for high coal desulfurization and char yield

Efficient pyrolytic desulfurization with high char yield is a promising yet challenging approach for the cleaner utilization of abundant high-sulfur coal reserves. In this study, we have discovered that a single pyrolysis process under either oxidizing or reducing conditions cannot efficiently remove various sulfur forms while preserving a high char yield. To address this challenge, we propose a three-stage desulfurization process: a low-temperature oxidative pyrolysis (LTOP), a high-temperature reductive pyrolysis (HTRP), and a dry magnetic separation process. LTOP operates in a fluidized bed for only a few minutes to oxidize the diamagnetic pyrite particle surface to Fe2O3 while minimizing char losses. HTRP occurs in another fluidized bed for an appropriate duration to substantially remove organic sulfur while reducing Fe2O3 to highly magnetic Fe3O4 or Fe. Partially magnetized pyrite particles are then removed from the char through magnetic separation. When applied to anthracite coal with a total sulfur content of 4.99%, this process achieves nearly 100% desulfurization for pyritic sulfur and 74.81% for organic sulfur. Ultimately, it recovers 94.5% of the original coal excluding volatiles as char, with 91.6% being low-sulfur char.

Influence of battery cell spacing on thermal performance of phase change material filled lithium-ion battery pack

The era of electric mobility has started, and petrol/diesel vehicles are being replaced by electric vehicles (EVs). The phase change material (PCM) is a trending field of research in its application of energy storage and thermal management. PCM-based thermal management method is found to be quite simple and effective for battery packs. However, its commercialization is difficult due to its low thermal conductivity and extra weight addition to the battery pack. Hence, the present research focuses on the battery performance with PCM. The experimental setup for a 48V, 25Ah battery pack is developed, and its performance is explored with and without PCM. The numerical model for same sized battery pack is developed, and validated with experimental results. The major objective of the present research is to find the optimal gap between two battery cells so that a sufficient amount of PCM can be filled inside the battery pack. Initially, inline and staggered cell arrangements are examined, and no significant difference in thermal performance is found. Further, cell spacing of 5 mm, 3 mm, and 1 mm are examined, and maximum temperature and temperature difference are compared along with the weight and volume of the battery pack. For a single charging process, 1 mm cell spacing is found sufficient, considering the weight of the battery pack and thermal performance. However, with 1 mm cell spacing, temperature increases significantly after each charging and discharging. At the same time, 3 mm and 5 mm are found as feasible solutions considering single and double charging-discharging cycles, respectively. 3 mm cell spacing is better option when weight is a critical issue, while 5 mm cell spacing is better when thermal performance is a critical issue. The current study offers guidance in the advancement of battery packs, particularly in cases where space constraints are a concern.

An insight into the catalytic properties and process optimization of Fe, Ni doped eggshell derived CaO for a green biodiesel synthesis from waste chicken fat

The basic theme of the current research work is based on the utilization of waste materials to produce environmentally friendly energy, i.e., waste + waste = energy. Efficacious and recyclable eggshell derived CaO, and transition metal doped CaO i.e. Fe-CaO, and Ni-CaO catalysts were used to synthesize biodiesel from chicken fat as a potential source of bioenergy. The synthesized catalysts were examined using a variety of analysis methods, such as FTIR, SEM, and XRD. Single step transesterification process gave 83% biodiesel yield using Fe-CaO. The characteristics of synthesized biodiesel were compared with international standards (ASTM6751 and EU14214).

Establishment of reaction engineering approach for saline droplet and its application in spray evaporation simulation

The statistical study of droplets in spray evaporation tower has guiding significance for understanding spray evaporation and designing drying tower. The key to spray evaporation simulation is establishing a suitable single droplet evaporation model through experiment. In this paper, a visualized single droplet evaporation experiment platform was established. The mass, diameter, and temperature during the evaporation of 10 % NaCl solution droplets were obtained. The Reaction Engineering Approach model was developed and validated to describe the single droplet evolution process in saline water spray. A comparison calculation between the spray evaporation of pure and saline water was executed, and the distributions of residence time of droplets were obtained. It reveals that droplets with initial diameters less than 117 μm can fully evaporate, and for larger droplets, pure water droplets represent a higher evaporation ratio. About 50 % of the fully evaporated saline droplets stay in the backflow area. Contrast numerical experiments of saline water spray evaporation were performed, concluded that similar performance can be attained with the same gas-liquid ratio, and excessive inlet air will reduce the residence time of droplets. The influence of other operating parameters on the performance was also discussed, providing a comprehensive understanding of the regularity of spray drying.

Physiochemical Coupled Dynamic Nanosphere Lithography Enabling Multiple Metastructures from Single Mask.

Metastructures are widely used in photonic devices, energy conversion, and biomedical applications. However, to fabricate multiple patterns continuously in single etching protocol with highly tunable photonic properties is challenging. Here, a simple and robust dynamic nanosphere lithography is proposed by inserting a spacer between the nanosphere assembly and the wafer. The nanosphere diameter decrease and uneven penetration of the spacer during etching lead to a dynamic masking process. Coupled anisotropic physical ion sputtering and ricocheting with isotropic chemical radical etching achieve highly tunable structures with various 3D patterns continuously forming through a single etching process. Specifically, the nanosphere diameters define the periodicity, the etched spacer forms the upper parts, and the wafer forms the lower parts. Each part of the structure is highly tunable through changing nanosphere diameter, spacer thickness, and etch conditions. Using this protocol, numerous structures of varying sizes including nanomushrooms, nanocones, nanopencils, and nanoneedles with diverse shapes are realized as proof of concepts. The broadband antireflection ability of the nanostructures and their use in surface-enhanced Raman spectroscopy are also demonstrated for practical application. This method substantially simplifies the fabrication procedure of various metastructures, paving the way for its application in multiple disciplines especially in photonic devices.

Social influence and social identity: A diffusion model analysis.

Building on the seminal studies of Solomon Asch and Muzafer Sherif, recent research has advanced our understanding of the mechanisms underlying social influence by applying a diffusion model analysis. Here, we combined the social identity approach to social influence with a diffusion model analysis to unravel the mechanisms underlying social influence. In particular, we aimed to disentangle whether the difference between in-group and out-group influence on perceptual decision-making is driven by a judgmental bias (i.e., changes in decision criteria) or a perceptual bias (i.e., changes in the uptake of sensory information). Preregistered analyses indicated that in-groups exerted stronger social influence than out-groups because in-groups induced a stronger perceptual bias than out-groups. This finding is in line with the single process assumption of the social identity approach because it implicates that the single process driving social influence (i.e., self-categorisation) translates into a change in a single subprocess of decision-making (i.e., biased information uptake). In conclusion, our results highlight that our theoretical understanding of social influence can be expanded by integrating the social identity approach with a diffusion model analysis.

Multifunctional finishes on photochromic microcapsule-printed cotton fabrics using titanium oxide nanoparticles

Purpose This paper aims to study the combination of photochromic microcapsules, which use the ultraviolet (UV) rays for colour changing phenomena, and titanium oxide (TiO2) nanoparticles (NPs), which block the UV rays by their photocatalytic activity in the sunlight on the cotton fabric. Design/methodology/approach The TiO2 NPs mixed with photochromic printing paste are used for coating on cotton fabric and further curing is performed in a one-step process. The photochromic pigment printed fabric impregnated in a liquid solution is processed in a two-step process with two variables such as 1% TiO2 and 2% TiO2. The characterization of samples was done with a UV transmittance analyser, surface contact angle, antimicrobial test and fabric physical properties. Findings The UV protection of TiO2-treated photochromic printed fabric was high and gives the ultraviolet protection factor rating of 2,000 which denotes almost maximum blocking of UV rays. The antibacterial activity of the one-step samples shows the highest 36 mm zone of inhibition (ZOI) against S. aureus (gram-positive) and 32 mm ZOI against E. coli (gram-negative) bacteria. The one-step sample shows the highest static water contact angle of 118.6° representing more hydrophobicity, whereas the untreated fabric is fully wetted (0.4°). In two-step processes, as the concentration of TiO2 increased, the antibacterial activity, UV blocking and hydrophobicity became better. Originality/value This work achieves the multifunctional finishes by using photochromic microcapsules and NPs in a single process as a first attempt. The results inferred that one-step sample has achieved higher values in most of the tests conducted when compared to all other sample.

Investigation of offshore landslides impact on bucket foundations using a coupled SPH–FEM method

BackgroundAs the exploitation of marine resources intensifies, the impact of submarine landslides on underwater structures has become a significant issue. Existing research primarily focuses on the impact on pipelines, often neglecting the actual deformation and mechanical response of underwater structures under impact loads in numerical simulations, thus complicating the evaluation of the reliability of these engineering structures in extreme conditions. Moreover, the dynamic response of bucket foundations, a common form of underwater base, under the effect of submarine landslide impacts remains unclear.MethodsTo address this knowledge gap, we have developed a fluid-structure coupling system that employs the coupled Smoothed Particle Hydrodynamics (SPH)-Finite Element Method (FEM) to investigate a single impact process and analyze the displacement response of bucket foundations within a water-offshore landslide-bucket foundationsubgrade context. The accuracy of this developed method has been systematically verified through comparisons with previous experimental and numerical results.ResultsDuring a submarine landslide impact event, the impact force demonstrates a distinct decrease followed by stabilization, and the displacement response of the bucket foundation exhibits a rebound effect after reaching its maximum value. Furthermore, we conducted an extensive analysis of different impact angles for underwater data centers equipped with multi-bucket foundations. Our study revealed that group-bucket foundations experience a combined translation-turnover failure when subjected to submarine landslide impacts, and the most unfavorable scenario for such impact is identified. The research introduces a novel numerical simulation approach for investigating the impact of submarine landslides on complex underwater structures.

Data-Driven Insights into Labor Progression with Gaussian Processes.

Clinicians routinely perform pelvic examinations to assess the progress of labor. Clinical guidelines to interpret these examinations, using time-based models of cervical dilation, are not always followed and have not contributed to reducing cesarean-section rates. We present a novel Gaussian process model of labor progress, suitable for real-time use, that predicts cervical dilation and fetal station based on clinically relevant predictors available from the pelvic exam and cardiotocography. We show that the model is more accurate than a statistical approach using a mixed-effects model. In addition, it provides confidence estimates on the prediction, calibrated to the specific delivery. Finally, we show that predicting both dilation and station with a single Gaussian process model is more accurate than two separate models with single predictions.

Field control of quasiparticle decay in a quantum antiferromagnet

Dynamics in a quantum material is described by quantized collective motion: a quasiparticle. The single-quasiparticle description is useful for a basic understanding of the system, whereas a phenomenon beyond the simple description such as quasiparticle decay which affects the current carried by the quasiparticle is an intriguing topic. The instability of the quasiparticle is phenomenologically determined by the magnitude of the repulsive interaction between a single quasiparticle and the two-quasiparticle continuum. Although the phenomenon has been studied in several materials, thermodynamic tuning of the quasiparticle decay in a single material has not yet been investigated. Here we show, by using neutron scattering, magnetic field control of the magnon decay in a quantum antiferromagnet RbFeCl3, where the interaction between the magnon and continuum is tuned by the field. At low fields where the interaction is small, the single magnon decay process is observed. In contrast, at high fields where the interaction exceeds a critical magnitude, the magnon is pushed downwards in energy and its lifetime increases. Our study demonstrates that field control of quasiparticle decay is possible in the system where the two-quasiparticle continuum covers wide momentum-energy space, and the phenomenon of the magnon avoiding decay is ubiquitous.

Sustainable coloration and analysis of cellulosic viscose fabric incorporating Rosa rubiginosa extraction and pre-mordanting approaches

Dyeing with natural ingredients has gained popularity as a sustainable option because of its numerous useful applications and favorable environmental impacts. The purpose of this study was to determine the optimal conditions for extracting natural dyestuff from the red rose flower (Rosa rubiginosa) by observing the coloring of viscose fabric. The parameters examined were the M:L ratio (1:3), temperature (80 °C), and duration (30 min). Infrared dyeing procedures were conducted on viscose fabric, employing a diverse range of mordants, both natural and synthetic, which included materials such as orange and lemon peels, tannic acid, copper sulfate, and ferrous sulfate, at different mordanting ratios. The highest results of the mordants were achieved by a single mordanting process called pre-mordanting, and their performances were compared for the first time. Here, utilizing orange peel as a natural mordant in a pre-mordanting procedure for dyeing viscose fabrics yields better results and enhanced performance than using any of the other mordants used. The CIELab results were calculated using a variety of measurement conditions, and the ideal value was determined by an experiment on the color strength (K/S) properties. The FTIR spectra confirmed the interaction of colored particles with viscose fabrics, and the SEM investigation confirmed the dye's ability to be absorbed into the fabric's surface. Elemental mapping and EDX spectroscopy both showed that there were dye particles floating about the surface of the colored fabric. The colorfastness ratings, including a rating of 4 for rubbing, 4–5 for washing, and 4 for lightfastness, were found to be satisfactory when the fabric was treated with metal mordants. Hence, Rosa rubiginosa used as a coloration of viscose fabric is a very promising alternative option to synthetic dyestuff, which can be used to satisfy the actual need for coloring and functionality of viscose fabric in the dyeing and finishing industry.

Effects of particle damper design parameters on the damping performance of laser powder bed fused structures

Particle dampers (PD), a passive damping technology, absorb energy from particle-particle and particle-cell wall interactions originating from friction and collision. PDs offer advantages such as design simplicity, low cost, applicability in harsh conditions, and flexibility to be used in a wide frequency band range. Additive manufacturing, specifically the powder bed fusion process, can fabricate structures with integrated PDs in a single printing process, eliminating the need to implement external dampers. However, the dynamic behavior of PDs must be determined to utilize their full potential. In this study, we examined 16 cases of integrated PDs by varying specific parameters including size, number, and locations on the structure to understand the effects of these parameters on the dynamic behavior of the first and second modes of the structure. Modal tests were conducted on additively manufactured samples to extract frequency response functions and calculate modal parameters (natural frequency and damping ratio) using the rational fraction polynomial method, studying the effects of PDs. The results showed that the damping performance of the parts was increased by a factor of up to 10 using body-integrated PDs compared with the fully fused specimen. The effectiveness of body-integrated PDs was shown to be strongly dependent on their volume and location. For instance, the damping generally increased as the volume fraction increased, which also reduced the total weight of the specimens by up to 60 g. Furthermore, the damping performance significantly increased for a specific mode when the PDs were located near the maximum displacement regions.

Kinetic studies of surfactant-aspirin micellization by means of ultrasonic relaxation spectroscopy

We report on the dynamics of the Sodium dodecyl sulfate (SDS) – aspirin micellization process taking place in aqueous environment by combining vibrational and ultrasonic spectroscopies. The experimental vibrational spectra have been compared with the corresponding theoretically predicted spectra obtained by density functional theory electronic structure calculations. The formation of a swollen SDS@aspirin micelle above a specific surfactant concentration significantly affects several physical properties of the system including surface tension and isentropic compressibility allowing the estimation of the critical micelle concentration. In the acoustic spectra, a single ultrasonic relaxation process has been detected in SDS-aspirin-water solutions at concentrations slightly above critical micelle concentration. The variation of the sound absorption coefficient and velocity as a function of frequency at different concentrations reveals the presence of a relaxation process attributed to the perturbation of the monomer-micelle dynamic equilibrium. We progress on the comprehensive understanding of the micellization kinetics, and the results are discussed in the context of several theoretical models of the field.

Tangential flow filtration for continuous processing of crystallized proteins

Protein crystallization has the potential to provide nearly pure protein products in a single processing step. Most previous studies of protein crystallization have used centrifugation for dewatering and washing the crystallized solids, but this approach would be difficult to adopt in continuous bioprocessing operations. This study provides the first demonstration that crystallized proteins can be successfully filtered using hollow fiber tangential flow filtration (TFF) modules. Experiments were performed with human serum albumin (HSA) crystallized by the addition of trivalent CeCl3, both with and without polyethylene glycol (PEG). Greater than 85 % protein yield was achieved using 4.5 mM CeCl3 in the presence of 3 wt% PEG with the crystallization occurring in less than 20 s, which is ideal for continuous processing. The addition of PEG had minimal effect on the crystallization yield, but it did lead to the formation of larger and denser crystals and a corresponding increase in the critical flux, which is the maximum value of the flux that causes minimal increase in the transmembrane pressure (i.e., minimal fouling). Filtration experiments performed at optimal conditions were successfully run for 24 h with the transmembrane pressure remaining below 5 kPa, demonstrating the feasibility of using continuous crystallization with tangential flow filtration for the purification of high value protein products.

Machine vision-based automatic focusing method for robot laser welding system

Background Defocus distance is a critical parameter in laser welding, especially when encountering changes in the contour of the welding surface. This paper proposed an automated focusing method to address the challenging issue of accurately adjusting the defocus distance. Methods The proposed method involves several steps. Firstly, a clarity evaluation function based on the Kirsch operator is employed to calculate real-time image clarity of the welding surface captured by the machine vision system. Next, an improved Canny edge detection algorithm is applied to identify the edge contours of the welding surface, from which their central points are extracted. Finally, automatic focusing is achieved by employing a variable step-size hill-climbing algorithm to search for the focal plane. Results To verify the applicability of the automatic focusing method proposed for welding the solder ring, a robot laser welding system was designed and constructed. Experimental results show that the positioning error of the robot after automatic focusing is within ±0.4 mm. The average time required for a single automatic focusing process is 16.27 s. These results demonstrated the successful accomplishment of automatic adjustment and control of the focal length. Conclusions The machine vision-based automatic focusing method proposed in this paper enhances the consistency of the robot’s position after automatic focusing in robot laser welding systems. It elevates the level of automation in the welding process and provides an efficient solution for accurately adjusting the welding focal distance during the laser welding process.

Mechanically Joined Extrusion Profiles for Battery Trays

In the context of electromobility, ensuring the leak tightness of assemblies is of paramount importance, particularly in battery housings. Current battery housings, often featuring base assemblies crafted from extruded aluminum profiles, address the challenge of leak tightness at joints through methods like friction stir welding, a process known for its time and cost intensiveness. The aim of this study is to develop and implement a new type of extruded profile concept to produce tight base assemblies for battery housings by a longitudinal mechanical single stroke joining process. The geometry, the process and the properties of the aluminum profiles are investigated to get a joint that meets the tightness requirements and achieve high load-bearing capacities in agreement with the high homologation requirements set to vehicles with high-voltage systems. The joint is formed by means of a single stage press stroke, which eliminates the need for complex tool designs that are necessary for continuous joining (roll joining). Flat steel contact surfaces are used as joining tools. To evaluate the joint quality, force curves from the joining process are analyzed and the resulting joint geometries are assessed using micrographs. The resulting leak tightness of the linear joints is measured by a helium sniffer leak detector and the load-bearing capacities are investigated by shear lap and bending tests and fatigue strength test. The study also explores whether a difference in strength between the two joining partners has a positive effect on the joint properties.