Simple Solution Research Articles

A density-controllable 3D measurement system based on linear profile sensor and universal manipulator

In order to offer a simple and efficient solution for obtaining point clouds, a modular 3D measurement system that incorporates an LPS mounted on a universal manipulator is developed. Unlike the requirement for electronic connections between the LPS and the robot to achieve hard synchronization, we employ a high-low-frequency collaborative strategy for soft synchronization, thereby eliminating the need for complex hardware synchronization modules. Since soft synchronization lacks the high-speed synchronous data acquisition of hard synchronization, we have also proposed an interpolation method on low density data to generate uniform higher-density point clouds, thus enabling a density-controllable point clouds acquisition approach. Experimental results demonstrate the effectiveness and versatility of the system.

Development and characterization of active poly (3-hydroxybutyrate) based composites with grapeseed oil and MgO nanoparticles for shelf-life extension of white button mushrooms (Agaricus bisporus)

Poly (3-hydroxybutyrate) (PHB) is undoubtedly a potential substitute for petroleum-based non-biodegradable food packaging materials due to its renewability, high crystallinity, biocompatibility, and biodegradability. Nonetheless, PHB exhibits certain shortcomings, including low flexibility, moderate gas barrier properties, and negligible antimicrobial and antioxidant activities, which limit its direct application in food packaging. Loading essential oils can increase flexibility and induce antimicrobial and antioxidant activities in biopolymers but at the cost of reduced tensile strength. In contrast, nanofiller reinforcement can increase the tensile strength and barrier properties of such biopolymers. Therefore, to harness the synergistic effects of essential oil and nanofiller, PHB-based films incorporated with 5 wt% grapeseed oil (GS) and varying concentrations (0.1–1 wt%) of MgO nanoparticles (MgO NPs) were prepared in this study following simple sonication-assisted solution casting technique. Physicochemical, tensile, microstructural, optical, barrier, antimicrobial, and antioxidant properties were then evaluated for the prepared composite films. FESEM analysis of the PHB-based films with 5 wt% GS and 0.7 wt% MgO NPs (PHB/5GS/0.7MgO) confirmed its compact morphology without any aggregates, pores, or phase separation. In comparison with pristine PHB, the PHB/5GS/0.7MgO films demonstrated higher tensile strength (by 1.4-fold) and flexibility (by 30-fold), along with 79 and 90 % reduction in water vapor and oxygen transmission, respectively. In addition, PHB/5GS/0.7MgO showed good UV-blocking properties, 65.25 ± 0.98 % antioxidant activity, and completely inhibited the growth of Staphylococcus aureus and Escherichia coli. Moreover, PHB/5GS/0.7MgO films proved beneficial effects in terms of extending the shelf-life of white button mushrooms up to 6 days at ambient room conditions.

AX·(H2SeO3)n (A = K, Cs; X = Cl, Br; n = 1, 2): A Series of Ionic Cocrystals as Promising UV Birefringent Materials with Large Birefringence and Wide Band Gap.

The design and syntheses of new birefringent crystals will be of great importance in commercial applications and materials science. A series of ultraviolet (UV) birefringent crystals, AX·(H2SeO3)n (A = K, Cs; X = Cl, Br; n = 1, 2), with large sizes up to 23 × 6 × 3 mm3, was successfully synthesized by simple aqueous solution method. These four compounds belong to three different space groups. Isomorphic KCl·(H2SeO3)2 and CsCl·(H2SeO3)2 crystallize in the space group, while CsBr·(H2SeO3)2 and CsCl·H2SeO3 crystallize in the P21/m and P21/c space groups, respectively. They exhibit cocrystal structures composed of [2(H2SeO3)]∞ and [AX]∞ frameworks, ingeniously inheriting the large optical anisotropy of selenite and the wide band gap of alkali metal halide. And it proves that these compounds indeed possess large birefringence (0.1-0.17 at 532 nm) and short UV cutoff edges (227-239 nm), achieving a balance of optical properties. This research affords a simple and viable strategy for the design and syntheses of new UV birefringent crystals. Besides, it is also found that the n value and ionic size (A and X ions) have important influences on the crystal structures and optical properties of AX·(H2SeO3)n. And this will promote further understanding of the alkali metal halide selenite family.

Dual-ended pumped high-power 915 nm Pr3+:LiYF4 laser and power scaling under energy levels cascade

We reported a high-power 915 nm Pr3+:LiYF4 (Pr:YLF) laser dual-ended pumped by laser diodes (LDs). The maximum output power of the laser was 3.39 W with a slope efficiency of 19.8 %. The fluctuation range of the laser wavelength was less than 0.58 nm. As far as we know, this is the highest power at 915 nm for LD-pumped Pr:YLF lasers to date. To eliminate the power saturation phenomenon and further improve the laser output power, we proposed a simple and effective method, i.e., laser energy levels cascade. Based on the experimental data, we calculated the populations of 3P0 and 1G4 energy levels in Pr:YLF crystal during laser cascading and developed two different models to verify the feasibility of the laser cascade mechanism. Moreover, the laser cascade could be realized merely by designing the lens film without introducing other devices, which provided a simple and effective solution for developing high-performance lasers.

Human behavior changing based on the simulation of the temperature control of a house

To optimize the energy consumption in a house, the behavior of the occupants must be changed. This can be achieved by providing information and suggestions to the occupants. Based on a web application, some suggestions can be offered only if it is available a thermal model of the house. This paper presents a simple solution for thermal modeling of a house which includes experimental identification of the parameters of the model, using a less expensive and noninvasive measurement system (indoor and outdoor temperatures and thermal energy consumption). Such data are used to simulate the thermal behavior of the house, to estimate the energy consumption and to obtain solutions to reduce energy consumption. In simulation, the control of the thermal system is performed using a model predictive control algorithm.

Nanoscale engineering of polypyrrole-silver oxide composites for rapid and ultrasensitive room temperature carbon monoxide detection

In this work, a silver oxide decorated Polypyrrole (Ag2O@Ppy) composites-based sensor was fabricated, for the first time, via a simple solution mixing method. Extensive materials characterization, via XRD, AFM, SEM, UV–vis, FTIR, and Raman spectroscopies, elucidated the tailored nanoarchitecture, unveiling Ag2O nanoparticle decoration homogenously encapsulating Ppy matrices. Systematic comparative gas sensing analysis demonstrated remarkably high sensitivity and selectivity towards CO versus other hazardous species (NH3, NO2, H2S, SO2). A superb 387% response at 300 ppm CO was achieved, significantly exceeding other gases. Remarkably, outstanding 156% response even at ultralow 10 ppm concentration reflected an exceptional limit of detection rivaling most sensors. Rapid, reversible response kinetics with 111 s reaction and 66 s recovery times arose from synergistic coupling between Ppy and Ag2O nanoparticles enabling expedited charge transfer. Excellent linearity spanned an ultrawide 10–600 ppm range. Unprecedented performance combined sensitivity, selectivity, speed, stability, and ambient temperature operation. The work unveils tremendously promising Ppy-Ag2O nanocomposites for next-generation chemiresistive CO monitoring critical for environmental safety and healthcare.

Cost-effective superhydrophobic ZnO films with adjustable wetting behaviors deposited via solution precursor plasma spray process

In this work, ZnO films featuring hierarchical micron−/nanometer-sized structures were deposited for adjusting wettability by a simple solution precursor plasma spray (SPPS) process using cost-effective zinc acetate solution. The effects of solution flow rate on the surface microstructures, surface roughness, crystalline orientation, and wetting behaviors of the films were investigated comprehensively. The results showed that high solution flow rate facilitated the formation of apparent hierarchical surface structures featuring more uniformly-distributed micron-sized protrusions and higher surface roughness. The increase of solution flow rate also promoted the crystalline growth along the non-polar (100) plane. With the solution flow rate increasing from 10 ml/min to 40 ml/min, the synergy of the surface structures and crystalline growth orientation resulted in a sharp decrease of the surface energy of the films from ~74.4 mJ/m2 to ~12.6 mJ/m2 and a dramatic elevation of water contact angles from ~130° to ~155°. The wetting states of different films were elucidated by correlating the wetting behaviors with the surface structures. The SPPS-deposited ZnO films showed high adhesion to water droplets, similar to the wetting behaviors of the petal effect, which could be used as a “mechanical hand” for non-loss microdroplet transfer. The work shows that SPPS represents a promising method to deposit cost-effective superhydrophobic films with adjustable wetting behaviors.

Tail Fan Necrosis syndrome in decapod crustaceans: A review.

Lobsters and crayfish in Australasia can develop a condition known as Tail Fan Necrosis (TFN syndrome). Many attempts have been made to find a primary pathogen or link the syndrome to commercial activities, but a solution remains elusive. TFN syndrome is a 'wicked problem', a problem difficult or impossible to solve because of incomplete and contradictory information forming a matrix of potential outcomes with no simple solution. Reviewing the literature shows TFN syndrome is sometimes reported to develop in association with sterile blisters on the telson and uropods which may rupture permitting invasion by environmental fungal and/or bacterial flora. Whether blisters form prior to, or because of, infection is unknown. TFN syndrome sometimes develops in captivity, sometimes requires a previous insult to the telson and uropods, and prevalence is patchy in the wild. The literature shows the cause of blisters associated with TFN syndrome remains an enigma, for which we suggest several possible initiating factors. We strongly urge that researchers not 'jump to conclusions' as to the aetiology of TFN syndrome. It cannot be explained without carefully exploring alternative aetiologies whilst being cognisant of the age-old lesson that 'correlation does not equal causation'.

Solid-State Lithium Batteries with Ultrastable Cyclability: An Internal-External Modification Strategy.

A commonly used strategy to tackle the unstable interfacial problem between Li1.3Al0.3Ti1.7(PO4)3 (LATP) and lithium (Li) is to introduce an interlayer. However, this strategy has a limited effect on stabilizing LATP during long-term cycling or under high current density, which is due in part to the negative impact of its internal defects (e.g., gaps between grains (GBs)) that are usually neglected. Here, control experiments and theoretical calculations show clearly that the GBs of LATP have higher electronic conductivity, which significantly accelerates its side reactions with Li. Thus, a simple LiCl solution immersion method is demonstrated to modify the GBs and their electronic states, thereby stabilizing LATP. In addition to LiCl filling, composite solid polymer electrolyte (CSPE) interlayering is concurrently introduced at the Li/LATP interface to realize the internal-external dual modifications for LATP. As a result, electron leakage in LATP can be strictly inhibited from its interior (by LiCl) and exterior (by CSPE), and such dual modifications can well protect the Li/LATP interface from side reactions and Li dendrite penetration. Notably, thus-modified Li symmetrical cells can achieve ultrastable cycling for more than 3500 h at 0.4 mA cm-2 and 1500 h at 0.6 mA cm-2, among the best cycling performance to date.

Surface stratification determines the interfacial water structure of simple electrolyte solutions

The distribution of ions at the air/water interface plays a decisive role in many natural processes. Several studies have reported that larger ions tend to be surface-active, implying ions are located on top of the water surface, thereby inducing electric fields that determine the interfacial water structure. Here we challenge this view by combining surface-specific heterodyne-detected vibrational sum-frequency generation with neural network-assisted ab initio molecular dynamics simulations. Our results show that ions in typical electrolyte solutions are, in fact, located in a subsurface region, leading to a stratification of such interfaces into two distinctive water layers. The outermost surface is ion-depleted, and the subsurface layer is ion-enriched. This surface stratification is a key element in explaining the ion-induced water reorganization at the outermost air/water interface.

Design of an efficient neural network model for detection and classification of phase loss faults for three-phase induction motor

AbstractIn industrial applications, three-phase induction motors (IMs) are widely used, and they are subjected to many types of faults. One such fault is the loss of a motor phase caused by a blown fuse, a broken wire, mechanical damage, etc. When this fault occurs during motor operation, it continues to rotate but experiences rapid heating, which can ultimately lead to motor failure. Therefore, various protection devices are available to protect the motor against this fault, but most traditional protection devices do not offer a comprehensive classification of such a fault. So, in this paper, an efficient neural network model is presented for detecting and classifying 12 types of phase loss faults for a three-phase induction motor (IM) based on factors such as the unhealthy phase, fault location, and motor action modes (standstill, transient, and steady-state modes). Thus, the main goal of this work is to determine the motor mode during the fault, the defective phase, and its location to help the maintenance team repair the fault quickly. The system is simulated and tested using the “MATLAB/Simulink” software, employing a feed-forward neural network. The simulation results demonstrate that the proposed network achieves correct detection and classification of phase loss faults within a short time frame from the occurrence of the fault. Therefore, the proposed network model proves to be a simple and reliable solution for integration into the protection system of a three-phase IM, enabling the detection and classification of various phase loss faults.

Anodic leaching plus chronopotentiometric aging of Ni2Fe ingot for sustainable oxygen evolution and urea oxidation reactions

A Ni–Fe binary alloy ingot, prepared by conventional vacuum smelting, was adopted as substrate in this work to fabricate the anode for water splitting. To improve the surface roughness of anode surface, the electrode was firstly subjected to anodic leaching in a simple KSCN solution. The as-leached electrode was subsequently activated through linear sweep voltammetry in 1 M KOH solution with or without 0.33 M urea addition to finish the final step for electrode preparation. The as-prepared anode delivers the 10 mA cm−2 current density at an overpotential of 284 mV for oxygen evolution reaction (OER) and at 1.361 V (RHE) for urea oxidation reaction (UOR), respectively. No apparent change of OER and UOR performance was observed after chronopotentiometric aging. The more complex UOR behavior was analyzed to elucidate the synergy among all constituents functioning through direct or indirect mechanisms for the half-reaction on this binder-free, self-supporting and substrate-rejuvenating anode.

Testing Weyl geometric gravity with the SPARC galactic rotation curves database

We present a detailed investigation of the properties of the galactic rotation curves in the Weyl geometric gravity model, in which the gravitational action is constructed from the square of the Weyl curvature scalar, and of the strength of the Weyl vector. The theory admits a scalar–vector–tensor representation, obtained by introducing an auxiliary scalar field. By assuming that the Weyl vector has only a radial component, an exact solution of the field equations can be obtained, which depends on three integration constants, and, as compared to the Schwarzschild solution, contains two new terms, linear and quadratic in the radial coordinate. In the framework of this solution we obtain the exact general relativistic expression of the tangential velocity of the massive test particles moving in stable circular orbits in the galactic halo. We test the theoretical predictions of the model by using 175 galaxies from the Spitzer Photometry & Accurate Rotation Curves (SPARC) database. We fit the theoretical predictions of the rotation curves in conformal gravity with the SPARC data by using the Multi Start and Global Search methods. In the total expression of the tangential velocity we also include the effects of the baryonic matter, and the mass to luminosity ratio. Our results indicate that the simple solution of the Weyl geometric gravity can successfully account for the large variety of the rotation curves of the SPARC sample, and provide a satisfactory description of the particle dynamics in the galactic halos, without the need of introducing the elusive dark matter particle.

PdCu alloy anchored defective titania for photocatalytic conversion of carbon dioxide into methane with 100% selectivity

The photoreduction of CO2 into CH4 with simultaneous high activity and selectivity is a promising strategy to increase energy supply and alleviate global warming. However, the absence of the active sites that is responsible for the adsorption and activation of CO2 and the generation of CO and H2 via side reactions often lead to poor efficiency and low selectivity of the catalyst. Herein, Cu, Pd, and PdCu metal clusters cocatalyst-anchored defective TiO2 nanotubes (Cu/TiO2-SBO, Pd/TiO2-SBO, and Pd1Cu1/TiO2-SBO) were designed via a simple solution impregnation reduction and applied for photocatalytic conversion of CO2 to CH4. The Pd1Cu1/TiO2-SBO photocatalyst exhibits excellent catalytic performance among the other catalysts for photoreduction of CO2 into CH4. More interestingly, the product selectivity of CH4 reaches up to 100% with a rate of 25 µmol g−1 h−1. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) simulations indicate that the main reasons for the high selectivity of CH4 are attributed to the PdCu alloy and oxygen vacancies, which jointly enhance the photoinduced carrier separation and lower energy barriers of key intermediates. Moreover, due to the tunable d-band center of the Cu site in the PdCu alloy, the generated intermediates can be well prevented from poisoning and promoted to participate in further reactions. Hopefully, the current study will provide insight into the development of new, highly selective photocatalysts for the visible light-catalytic reduction of CO2 into CH4.

Solution blending preparation of polyurethane/graphene composite: Improving the mechanical and anti-corrosive properties of the coating on aluminum surface

Graphene-based polyurethane composites (PU/G) are prepared by a simple solution blending method to disperse defect-free graphene flakes (prepared via liquid phase exfoliation process) into the polyurethane matrix. The PU/G composite with 1 wt% of graphene flakes performs the significant improvement (∼50 %) of the impact strength (124 kg.cm) and adhesion behavior (∼2.3 MPa) with respect to that of pristine PU. The PU/G coating with 2 wt% of graphene achieves the highest long-term anti-corrosion performance after 150 immersed days in 3 wt% NaCl solution (with the stable impedance modulus of ∼2.7 × 1010 Ω.cm2) or after 2500 h of salt spray exposure in 5 wt% NaCl solution (no corrosive traces detected on aluminum substrate).

Finite element analysis of temperature distribution in 3YSZ ceramics during conventional sintering

AbstractThe presence of a temperature gradient (if any) within the ceramic sample is casually ignored during the sintering of ceramic shapes. The present work exposes some serious repercussions of such a thought process and provides simple solutions to mitigate the same; 3 mol.% yttria‐doped zirconia ceramic was used for this study. With the help of the combinatorial finite element analysis (FEA) model and real‐life experiments, our work illustrates the complex interplay of heat transfer mechanisms and reveals the dynamic nature of temperature distribution during the heating and cooling cycles of ceramics. Although the rate of heating is usually assigned as the most important factor during sintering, the present study shows that variations in heat transfer mechanism and sample geometry contribute very strongly to overall temperature distribution during the heating, holding, and cooling cycles. Along with of vertical positioning of the samples (inside the furnace), a bottom supporting ceramic plate with a high thermal conductivity can also help in reducing the temperature gradient between the top and bottom of the ceramic samples. Overall, exposing the sample most for the radiative heat transfer holds the key to successful sintering in order to avoid any phase, compositional, or microstructural heterogeneity across the thickness of the specimen.

Navigating "Wicked Problems" in Public Policy: The Power and Promise of Using SHAMROQ's Transdisciplinary Approach to Find Regulatory Text Patterns – A Mixed Method Study

In an era marked by significant public policy challenges, including climate change, public health, and economic inequality, traditional bureaucratic or technocratic methods prove increasingly inadequate. These so-called "wicked problems," characterized by their complexity and resistance to simple solutions, require more dynamic, inclusive approaches, that transcend jurisdictional boundaries. Embracing these approaches, we extend SHAMROQ, a novel transdisciplinary approach that combines Software Engineering, Artificial Intelligence, Linguistics, and Logic to extract, classify, and model deontic expressions from regulatory texts. This mixed-method study examines three CFR titles: Title 16 Commercial Practices, Title 45 Public Welfare, and Title 48 Federal Acquisition Regulations Systems, with an emphasis on the distribution of deontic expressions and identifying challenges in regulatory text. The results, supported by a chi-square test of independence with a highly significant p-value < .001 , show a strong association between deontic expression types and CFR Titles. This research also provides deeper insights into regulatory language complexity by broadening the analysis across CFR Titles 16, 45, and 48. Title 16 features diverse permissions and obligations, reflecting commercial law's complexity. Title 45 uses strict directives like 'must' and 'shall' for public welfare compliance, while Title 48 focuses on obligatory terms for federal acquisition, aligning with procurement demands. Such insights can inform future research and practical applications in regulatory analytics, compliance, and public policy.

Vibration analysis of metallic structure of an innovative dam gate

An analysis of the vibrations that may occur at the gate of a dam is proposed. Thus, the determination of an optimal constructive solution is sought from the point of view of vibration behavior. The dam gate is part of a constructive solution of an oscillating center pivot dam, which closes the gates if the downstream water level rises above a certain limit. This constructive solution is new. The gates are controlled by the water level. Such a system is easy to implement practically and the construction and maintenance costs are lower than in the case of classic dams. The problem that arises is that of the behavior of such a structure to vibrations. The eigenvalues of the gate structure are determined for a constructive solution proposed by the designers and the behavior of the forced vibrations that can stress the gate is studied. The analysis is performed for the case where the dam gates are closed. The work continues previous research on the structure's resistance to static loads and justifies the use of this solution in design. The method used to carry out the study is the finite element method. The advantages of the studied structure consist of lower costs for the proposed relatively simple constructive solution.

System-Based Protection Method for High-Voltage Pulse Generator Switching Units in Biomass Electroporation

Background High-voltage pulsed electric field (PEF) technology has emerged as a promising technique for enhancing cell membrane permeabilization for biotechnological and medical applications. Given the parametric instability and low resistivity of biomass when used it as an electrical load, it is imperative for the switching unit to meet specific requirements in terms of load capacity and protection against overloads and short circuits. Methods To construct generators capable of producing high-voltage pulses in the microsecond and millisecond duration ranges, we are incorporating a switching unit that employs a hardware-software method to safeguard critical transistors against overloads and short-circuit currents. Our strategy revolves around utilizing the energy storage capacitor (ESC) both as a means of energy storage and as a current sensor. By monitoring the voltage drop during discharge, we can accurately estimate current parameters. The occurrence of an excessively rapid discharge from the ESC serves as an indicator of a short circuit. The microcontroller calculates ESC discharge limits based on preset parameters within a defined timeframe. Should this limit be exceeded, the system promptly interrupts to address the pulse responsible for the short circuit and halts the further supply of remaining pulses to the load. This sophisticated approach ensures the protection and integrity of the system in the face of potential overloads or short circuits. Results Applying a systemic approach in the design of the presented implementation of protection for key transistors in the switching node from overload and short-circuit current for high-voltage pulse generators (HVPG) in the microsecond and millisecond duration ranges allows for a simpler circuit solution. In this case, the system approach also provides a unified control principle when implementing the considered option for organizing protection, regardless of the number and type of transistors or solid-state switching modules used and connected in parallel. Conclusions The configuration and protective circuitry presented in the article are specifically tailored for shielding switching elements from short-circuit currents, with a primary focus on their application in high-voltage pulse generators (HVPG). These generators are commonly employed in the high-voltage pulse treatment of diverse and unstable loads during the electroporation of biomass. The technical solution expounded in the article is intended for use in the switching nodes of HVPG, particularly those with discharge circuits constructed based on a direct capacitive discharge scheme. Notably, this protection configuration introduces local innovation and is characterized by the circuit's simplicity, achieved through the effective utilization of existing system resources. This protective variant for HVPG switches is particularly well-suited for devices utilized in versatile technological installations with relatively lower performance levels.

Suppressing Redox Reactions at the Perovskite-Nickel Oxide Interface with Zinc Nitride to Improve the Performance of Perovskite Solar Cells.

For p-i-nperovskite solar cells (PSCs), nickel oxide (NiOx) hole transport layers (HTLs) are the preferred interfacial layerdue to their low cost, high mobility, high transmittance, and stability. However, the redox reaction between the Ni≥3+ and hydroxyl groups in the NiOx and perovskite layer leads to oxidized CH3NH3 + and reacts with PbI in the perovskite, resulting in a large number of non-radiative recombination sites. Among various transition metals, an ultra-thin zinc nitride (Zn3N2) layer on the NiOx surface is chosen to prevent these redox reactions and interfacial issues using a simple solution process at low temperatures. The redox reaction and non-radiative recombination at the interface of the perovskite and NiOx reduce chemically by using interface modifier Zn3N2 to reduce hydroxyl group and defects on the surface of NiOx. A thin layer of Zn3N2 at the NiOx/perovskite interface results in a high Ni3+/Ni2+ ratio and a significant work function (WF), which inhibits the redox reaction and provides a highly aligned energy level with perovskite crystal and rigorous trap-passivation ability. Consequently, Zn3N2-modified NiOx-based PSCs achieve a champion PCE of 21.61%, over the NiOx-based PSCs. After Zn3N2 modification, the PSC can improve stability under several conditions.