Deposition Efficiency Research Articles

Effect of arc deposition process on mechanical properties and microstructure of TiAlSiN gradient coatings

In order to successfully prepare a new advanced TiAlSiN gradient coating with Ti content gradually decreased but Al content gradually increased from the cemented carbide substrate to the outermost coating surface by arc ion plating, we deeply investigated the influence mechanisms of two important process parameters. These parameters include substrate bias voltage and arc current, which affect the mechanical properties and microstructure of the gradient coating. The results show that bias voltage and arc current directly affect the particle accumulation effect on the coating surface and the re-sputtering effect caused by high-energy ion bombardment, thus affecting the deposition efficiency of the coating and the formation of defects such as macro-particles and pits on the coating surface. The increase of bias voltage is conducive to the increase of the density of columnar crystals and nanocrystals. While the increase of arc current makes the coating with high Al content transform from columnar crystals to nanocrystals. The hardness and interfacial adhesion of the gradient coatings showed a tendency of firstly increasing and then decreasing with the increase of both bias voltage and arc current. When the bias voltage and arc current are -80 V and 160 A respectively, the coating has the best mechanical properties, its surface hardness reaches 36.94 GPa, and the interfacial adhesion exceeds 120 N. In addition, with the increase of bias voltage and arc current, particles are deposited on the surface of the coating with higher energy, which leads to the preferential orientation transition from (111) to (200) plane. The high hardness of TiAlSiN coating is mainly due to the formation of high Al content of fcc-TiAlN crystals and amorphous Si3N4 in the gradient-coated surface layer. The results have important theoretical and practical significance for developing new high-performance gradient coating tools.

Inhalable tobramycin EEG powder formulation for treating Pseudomonas aeruginosa-induced lung infection

Pulmonary delivery of antibiotics is an effective strategy in treating bacterial lung infection for cystic fibrosis patients, by achieving high local drug concentrations and reducing overall systemic exposure compared to systemic administration. However, the inherent anatomical lung defense mechanisms, formulation characteristics, and drug-device combination determine the treatment efficacy of the aerosol delivery approach. In this study, we prepared a new tobramycin (Tobi) dry powder aerosol using excipient enhanced growth (EEG) technology and evaluated the in vitro and in vivo aerosol performance. We further established a Pseudomonas aeruginosa-induced lung infection rat model using an in-house designed novel liquid aerosolizer device. Notably, novel liquid aerosolizer yields comparable lung infection profiles despite administering 3-times lower P. aeruginosa CFU per rat in comparison to the conventional intratracheal administration. Dry powder insufflator (e.g. Penn-Century DP-4) to administer small powder masses to experimental animals is no longer commercially available. To address this gap, we developed a novel rat air-jet dry powder insufflator (Rat AJ DPI) that can emit 68–70 % of the loaded mass for 2 mg and 5 mg of Tobi-EEG powder formulations, achieving a high rat lung deposition efficiency of 79 % and 86 %, respectively. Rat AJ DPI can achieve homogenous distribution of Tobi EEG powder formulations at both loaded mass (2 mg and 5 mg) over all five lung lobes in rats. We then demonstrated that Tobi EEG formulation delivered by Rat AJ DPI can significantly decrease CFU counts in both trachea and lung lobes at 2 mg (p < 0.05) and 5 mg (p < 0.001) loaded mass compared to the untreated P. aeruginosa-infected group. Tobi EEG powder formulation delivered by the novel Rat AJ DPI showed excellent efficiencies in substantially reducing the P. aeruginosa-induced lung infection in rats.

Impact of the Different Molecular Weights of Polyethylene Glycol (PEG) Coating Agents on the Magnetic Targeting Characteristics of Functionalized Magnetoresponsive Nanoclusters

In this article, we investigated the influence of molecular weight (Mw) on particle deposition efficiency after PEG-functionalized (polyethylene glycol-PEG) magnetoresponsive magnetic cluster targeting. In this work, the clusters were obtained by the solvothermal polyol method using polyethylene glycol (PEG) as a coating agent. So, we investigated three kinds of magnetoresponsive clusters: MNC-2000, MNC-6000, and MNC-10,000. These clusters were coated with PEG, and had molecular weights (Mw) of 2000 Da, 6000 Da, and 10,000 Da, respectively. The authors propose that the key to achieving maximum efficiency in targeted drug delivery is to deposit a thin, uniform layer of medication that covers the vascular wall in the area of interest. We defined a set of efficiency criteria to focus on the most essential characteristics of the targeting results. These are the obstruction degree, which measures the level of vessel obstruction; the magnet coverage degree, which evaluates the quality of particle deposition along the vessel wall; and the proximal deposition degree, which assesses the effect of pulsatile flow on deposition length. We performed several tests to determine how molecular weight affected these efficiency parameters. These tests examined (a) the effect of the injected cluster quantities, (b) the effect of the magnet distance, and (c) the effect of the injection period. Our findings indicate that an increase in PEG’s molar weight significantly impacts magnetic particle targeting efficiency.

New method for high-efficiency keyhole-based wire direct energy deposition: Process innovation and characterization

Wire laser direct energy deposition enables the mass production of large-scale industrial components and parts. However, energy utilization efficiency is limited in conventional wire laser material deposition to avoid keyhole defects, resulting in a low deposition efficiency. This work presents a high-efficiency wire laser material deposition process that increases energy utilization by generating a keyhole in the filler wire, which can also avoid the keyhole defects in the deposited sample. The influence of process parameters on deposition quality and efficiency was thoroughly examined to determine the process window. A high deposition efficiency of 0.87 kg/(h kW) for 316L stainless steel was achieved with a laser power of 3 kW, approximately three times that of the conventional wire laser material deposition process. The defect-free multitrack and multilayer deposition demonstrated the feasibility of our proposed high-efficiency process.

Two-Parameter Probabilistic Model and Experimental Research on Micron Particle Deposition

The deposition of micron particles in gas pipelines has always been an important problem in ultra-clean ventilation technology in the modern laser fusion, precision electronics, aerospace, and biomedical fields. Combining the mathematical expression of the migration, collision, and deposition of micron particles in a gas pipeline with a simulation of flow fields, a two-parameter particle probability deposition model based on vinl, θcr and collision probability coefficient PP is established, and the distribution law of particle deposition, considering two deposition targets of the pipe wall and deposition layer, is given. Combined with an experiment on particle migration and deposition in a gas pipeline, an interpretation and verification of the particle deposition distribution law are given, and the difference between the model and experiment is discussed through particle deposition efficiency mass distribution. Studies have shown the following: Under the premise of two kinds of deposition targets, different particle sizes in the gas pipeline present different deposition laws; the deposit morphology is a spot deposit of 10 µm particles and a flake deposit of 40 µm particles; the deposit position shows a uniform distribution and a lower wall dominance; and the deposit concentration area of 40 µm shows a more significant distribution. The results are very important for the selection and optimization of gas pipelines for clean spaces.

Carbon cloth with lithiophilic carbon-coated ZnO nanotubes as anode current collector for hybrid lithium ion/lithium metal battery

Reasonable design of light-weight carbon-based current collector is a promising strategy to enable high-energy-density lithium batteries. Herein, carbon-coated ZnO nanotube arrays with good lithiophilicity are constructed on carbon cloth, which is used as anode current collector to construct hybrid lithium ion/lithium metal battery. The modified carbon cloth effectively promotes the formation of robust and inorganic-rich solid electrolyte interphase, which consists of mixed ionic-electronic conductive (MIEC) interface with ion-conductive Li2O/LiC6 and electron-conductive LiZn alloy. Rapid electron/ion transportation during repeated lithium plating/stripping is realized by the Li2O/LiZn/LiC6 MIEC arrays, which homogenizes the lithium deposition and ensures uniform dendrite-free Li deposition. The three-dimensional structure of the current collector also provides enough space to constrain the lithium deposition and avoid the huge volume change. As a result, continuous anode-electrolyte interfacial side reactions and active lithium loss are effectively suppressed. Uniform Li deposition and high average Coulombic efficiency are achieved in the hybrid lithium ion/lithium metal cell. The capacity retention of full cell with carbonate-based electrolyte maintains 47.0 % after 600 cycles, and the full cell also shows superiority in rate performance and energy density. This work provides a promising alternative for light-weight anode current collector to enable high-energy-density lithium batteries.

Effect of Ti3SiC2 concentration on corrosion resistance and ICR in bipolar plates composite ceramic coatings

Ti3SiC2, a MAX-phase ceramic, amalgamates metallic and ceramic traits, delivering exceptional electrical conductivity and corrosion resistance. In this research, Ti3SiC2 composite coatings were applied to 316 L stainless steel via low-power atmospheric plasma spraying (APS), aiming to bolster the electrical and corrosion resistance attributes of bipolar plates (BPPs). A power input of 15 kW notably enhanced coating density, yielding a Ti3SiC2 concentration of 19.2 wt% in the coating. Extremes in the spraying power led to either diminished deposition efficiency or a reduction of Ti3SiC2 mass fraction below 5 wt%. Tafel curves demonstrated that specimens with elevated Ti3SiC2 mass fractions exhibited robust corrosion resistance, characterized by a self-corrosion potential of −162.5 mV and a self-corrosion current density of 1.7217 × 10−6 A·cm−2. Moreover, the interfacial contact resistance (ICR) between the coating and the gas diffusion layer was remarkably low (down to 5.49 mΩ·cm−2), indicating enhanced surface electron transfer with increasing Ti3SiC2 mass fractions.

Improving the formability and quality of CMT additively manufactured aluminum thin-wall parts via laser stabilization effect

In the recent past, the deposition efficiency has been one of the most concerned problems in aluminum additive manufacturing. In this research, a comparative study on the formation quality, microstructures and mechanical properties of aluminum alloy thin-wall structures between the oscillating laser-arc hybrid additive manufacturing (O-LHAM) and wire-arc additive manufacturing (WAAM) at high deposition speed was performed. The formation quality of the additively manufactured thin-wall parts under O-LHAM was significantly improved compared with WAAM. The molten pool overflow was significantly eliminated due to the higher support force on the molten pool, thus the surface roughness Sa and the maximum surface height difference Sz of O-LHAM thin walls were reduced by 13% and 22%, respectively. Compared with thin wall manufactured via WAAM, the microstructure of O-LHAM mainly consisted of coarse columnar grains and showed anisotropic characteristics due to the increased heat accumulation. Moreover, owing to the higher porosity in the interlayer combination regions of WAAM sample, the elongation of thin walls manufactured via O-LHAM was higher than WAAM in both horizontal and vertical directions, reaching 36.8% and 32.5%, respectively. This work will provide more guidance on thin-wall additive manufacturing with high deposition efficiency.

Aerosol exposure at air-liquid-interface (AE-ALI) in vitro toxicity system characterisation: Particle deposition and the importance of air control responses

Experimental systems allowing aerosol exposure (AE) of cell cultures at the air-liquid-interface (ALI) are increasingly being used to assess the toxicity of inhaled contaminants as they are more biomimetic than standard methods using submerged cultures, however, they require detailed characterisation before use. An AE-ALI system combining aerosol generation with a CULTEX® exposure chamber was characterised with respect to particle deposition and the cellular effects of filtered air (typical control) exposures. The effect of system parameters (electrostatic precipitator voltage, air flowrate to cells and insert size) on deposition efficiency and spatial distribution were investigated using ICP-MS and laser ablation ICP-MS, for an aerosol of CeO2 nanoparticles. Deposition varied with conditions, but appropriate choice of operating parameters produced broadly uniform deposition at suitable levels. The impact of air exposure duration on alveolar cells (A549) and primary small airway epithelial cells (SAECs) was explored with respect to LDH release and expression of selected genes. Results indicated that air exposures could have a significant impact on cells (e.g., cytotoxicity and expression of genes, including CXCL1, HMOX1, and SPP1) at relatively short durations (from 10 mins) and that SAECs were more sensitive. These findings indicate that detailed system characterisation is essential to ensure meaningful results.

Design of laser-powder coupling for high-speed laser direct energy deposition

High-speed laser direct energy deposition (DED-LB) is developed to enhance deposition efficiency while maintaining build quality, compared to conventional DED-LB. The core of designing high-speed DED-LB involves formulating the laser-powder coupling, through optimizing nozzle structural and deposition process parameters. This study developed an analytical model to delineate the coupling mechanisms between laser beam and discontinuous coaxial powder stream (DCPS) comprised of individual single powder streams (SPSs). A data pretreatment method, involving gray processing, normalization, and renormalization of the thermal images successively, was applied to validate the model. Simulation results indicate that the DCPS spot size and SPS particle temperature distribution are predominantly influenced, respectively, by the nozzle structural and deposition process parameters. Through jointly designing the nozzle structural and deposition process parameters, a high deposition rate of high-speed DED-LB, which is 1.7 times that of conventional DED-LB, was achieved. This paper pioneers a new design methodology for high-speed DED-LB.

Effective removal of uranium (VI) with a SDBS doped PPy-SUS304 electrode from alkaline wastewater using electrodeposition strategy

The immobilization of uranium in nuclear wastewater is of paramount importance for environmental and human health. However, there is a paucity of research on the immobilization of uranium in alkaline wastewater, particularly with regards to the application of novel electrodes. This article presents the utilization of an electrochemically polymerized polypyrrole stainless steel (PPy-SUS304) electrode for the effective electrochemical deposition and removal of uranium from alkaline wastewater containing uranium. According to the electrodeposition results, the uranium deposition efficiency of the novel electrode reached 96.82 %, with a uranium deposition rate of 0.048 mg U/(h·cm2) and a charge efficiency of 0.055 mg U/C. These findings demonstrate the successful electrochemical reduction of UO2(CO3)34- in alkaline uranium-containing wastewater using the novel electrode, resulting in improved charge deposition efficiency. The electrode surface products were investigated using scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), and X-Ray Photoelectron Spectroscopy (XPS). The SEM and EDS results demonstrate the formation of a uniform PPy film on the surface of SUS304. In addition, the White light interferometer (WLI) test reveals that the PPy-SUS304 electrode exhibits increased roughness compared to the SUS304 electrode. The XPS results revealed that the electrode surface products of PPy-SUS304 were actually U compounds constituted of U(IV) oxides or hydroxides. This study provides a new perspective for the development of novel electrodes to suppress side reactions and efficiently recover uranium from alkaline uranium-containing wastewater.

Comparative effects of various dietary selenium sources on growth performance, meat quality, essential trace elements content, and antioxidant capacity in broilers

This study aimed to compare the effects of various dietary selenium (Se) sources (0.5 mg/kg) on performance, meat quality, and antioxidant capacity in broilers as well as essential trace elements concentrations in their blood and tissues. A total of 360 one-day-old male yellow-feathered chickens (37.00 ± 0.17 g) were randomly allocated to 5 diet treatments: the basal diet (CON) and 4 diets supplemented with sodium selenite (SS), selenomethionine (SM), selenium-enriched yeast (SY), and nano-selenium (NS) for 56 d, respectively, with 6 replicates per treatment and 12 chickens per replicate. Dietary Se supplementation did not affect growth performance and carcass characteristics in broilers (P > 0.05). Supplemental SM enhanced the redness in the pectoral muscle compared to CON and NS (P < 0.05). Supplementation of SY and NS improved the concentrations of Se, copper, manganese, and zinc in the serum (P < 0.05). Supplemental SS also elevated the zinc content in the serum (P < 0.05). Broilers fed the SY diet showed increased Se content in the liver and pectoral muscle compared to those fed CON, SM, and NS diets (P < 0.05). Also, SY improved the pectoral muscle Se concentration compared to SS (P < 0.05). Besides, dietary Se supplementation increased the Se content in the thigh muscle (P < 0.05), with SY showing highest Se deposition. Dietary supplementation with SS, SM, and NS improved the activities of total superoxide dismutase and total antioxidant capacity (T-AOC) in the serum (P < 0.05). Supplemental SY also elevated the T-AOC in the serum (P < 0.05). Additionally, SS and SM enhanced the T-AOC in the liver (P < 0.05). In conclusion, supplemental SM affected meat color. Supplementing diets with various Se sources increased antioxidant capacity and Se content in the thigh muscle of broilers, with SY showing a more pronounced deposition efficiency. Besides, diets supplemented with different Se sources had variable effects on the concentrations of essential trace elements in the serum and tissues of broilers.

PM2D: A parallel GPU-based code for the kinetic simulation of laser plasma instabilities at large scales

Laser plasma instabilities (LPIs) have significant influences on the laser energy deposition efficiency and therefore are important processes in inertial confined fusion (ICF). Numerical simulations play important roles in revealing the complex physics of LPIs. Since LPIs are typically a three wave coupling process, the precise simulations of LPIs with kinetic effects require to resolve the laser period (around one femtosecond) and laser wavelength (less than one micron). In the typical ICF experiments, however, LPIs are involved in a spatial scale of several millimeters and a temporal scale of several nanoseconds. Therefore, the precise kinetic simulations of LPIs in such scales require huge computational resources and are hard to be carried out by present kinetic codes like particle-in-cell (PIC) codes. In this paper, a full wave fluid model of LPIs is constructed and numerically solved by the particle-mesh method, where the plasma is described by macro particles that can move across the mesh grids freely. Based upon this model, a two-dimensional (2D) GPU code named PM2D is developed. The PM2D code can simulate the kinetic effects of LPIs self-consistently as normal PIC codes. Moreover, as the physical model adopted in the PM2D code is specifically constructed for LPIs, the required macro particles per grid in the simulations can be largely reduced and thus overall simulation cost is considerably reduced comparing with PIC codes. More importantly, the numerical noise in the PM2D code is much lower, which makes it more robust than PIC codes in the simulation of LPIs for the long-time scale above 10 picoseconds. After the distributed computing is realized, our PM2D code is able to run on GPU clusters with a total mesh grids up to several billions, which meets the requirements for the simulations of LPIs at ICF experimental scale with reasonable cost. Program summaryProgram Title: PM2DCPC Library link to program files:https://doi.org/10.17632/xscj6vnkkw.1Licensing provisions: GNU General Public License v3.0.Programming language: C++, CUDA.Nature of problem: Although the large scale simulations of laser plasma instabilities (LPIs) is of great significance for the inertial confinement fusion (ICF), there is still no suitable code to simulate these problems. PM2D code based on a GPU platform provides an effective method to simulate these large scale problems in ICF.Solution method: A fluid model for LPIs is established firstly, which contains wave equations that describe the laser propagating process, electron and ion fluid equations that describe the plasma motions, and a Poisson's equation that describes the electrostatic field induced by charge separation. The wave equation is solved on a rectangular region using absorption boundary conditions on all of four boundaries. The absorption boundary condition on the left boundary is further extended to allow the incidence of driven lasers and absorption of scattering lasers simultaneously. The fluid equations in the physical model are solved by the particle-mesh method, in which the macro particles are driven to move by fluid forces. Since macro particles can move freely within the fixed fluid grids, the PM2D code can capture the kinetic effects self-consistently. The Poisson's equation for the electrostatic field is solved by a Fourier decomposition method in the y direction, which helps to decrease the simulation cost greatly. The PM2D code is developed on a GPU platform base on CUDA toolkit, which largely increase the computational speed.

Studies on the reduction of dispersed emissions from a low-power household boiler in a plasma ionic wind zone

Gas ionizator is a device for electrostatic precipitation and is widely used to separate fine particulate matter (FPM) from small- and large-scale industrial exhaust gases. Two variations of electrodes design, rod and rectangle-toothed saw were used. The mass and number concentrations of six FPM fractions were detected. Stronger vortices occur at higher EAD/Re2 ratios compared to the secondary electroaerodynamic (EAD) gas velocities. A deposition efficiency higher than 94.9 % was achieved at a gas velocity of 0.2 m/s. The FPM capture efficiency at voltage up to 20 kV is higher more than 7 % than at a voltage of 15 kV.

Melt pool control-assisted additive manufacturing of thin-walled parts

Thin-walled aerospace components manufactured by laser directed energy deposition are susceptible to thermal accumulation effects owing to their deposition path and efficiency, further leading to the edge collapse. The melt pool width, as the carrier of thermal input, is an important geometric factor reflecting the state of the melt pool. Therefore, an in-situ melt pool control technique was proposed. The melt pool width as the control target was monitored using a coaxial camera, and the laser power was adjusted in real time based on the proportional-integral-derivative algorithm. A thermal accumulation model in conventional mode and a thermal suppression model in control mode were derived. The surface roughness, porosity, microstructure, and tensile properties of AISI 316 L stainless steel were compared between two modes. The results demonstrated that the roughness and porosity of thin-walled parts were respectively reduced by 45.3% and 82.7% after control. The periodic evolution of interlayer columnar and equiaxed crystals, and the increase in deformation twins contributed to a simultaneous increase in tensile strength and toughness, with a maximum increase of 35.7% in elongation.

Extraction of crop canopy features and decision-making for variable spraying based on unmanned aerial vehicle LiDAR data

Implementation of precision agriculture aerial applications using unmanned aerial vehicles (UAVs) represents a pivotal technological aspect in precision agriculture. However, current UAV applications are still far from realizing true precision variable spraying. The use of UAVs to analyze and model crop growth, pest and disease conditions, and other pertinent information to enable targeted precision spraying poses a formidable challenge. Herein, a UAV variable-rate spray system with adaptive flow control based on crop canopy morphology was developed using a UAV equipped with a light detection and ranging (LiDAR) sensor to support precision spraying of cotton. Point cloud data captured by the LiDAR sensor initially undergo processing using the simple morphological filter (SMRF) algorithm and feature extraction function. Subsequently, cotton canopy volumes measured by the alpha shape algorithm, convex hull by slices shape algorithm, and voxel-based method were compared with manual measurements with coefficient of determination R2 values of 0.89, 0.78, and 0.82, respectively. The results of the validation experiments denote that the cotton canopy volume obtained using the alpha shape algorithm is in good agreement with that obtained using manual measurements; thus, this algorithm is employed for volume calculations in this design. Models were constructed to relate UAV flight parameters, cotton canopy volume, and spraying parameters to the duty cycle of variable control signals, which enabled the UAV to adjust the flow rate in real time to match the cotton canopy structure. In addition, a polygonal prescription map decoding algorithm based on the cotton canopy morphology was introduced. This algorithm is used for real-time decoding of prescription maps and extraction of flow, latitude, and longitude information. Finally, field experiments were conducted, and the results indicate that the UAV variable-rate spray system designed in this study exhibits biological efficacy (effective application thresholds provided by the pesticide manufacturer) comparable to that of the constant-rate spray system at a lower application rate. Furthermore, it exhibited superior spray deposition efficiency and coverage compared with the constant-rate spray system. Notably, the use of the variable-rate spray system in cotton crops resulted in a 43.37% reduction in spray volume while maintaining high application quality, providing an opportunity for pesticide and labor cost savings.

Research and improvement of the design of a sedimentation tank for hydropower and irrigation

The study is devoted to the analysis and optimisation of the design of the sedimentation tank to increase the efficiency of settling solid particles in hydropower and irrigation systems. Both experimental and numerical methods were used to analyse and optimise the design of sedimentation tanks to increase their efficiency in hydropower and irrigation systems. The study examined and analysed various types of sedimentation tanks according to design schemes, flow regime, deposition dynamics and sediment flushing methods, and also considered recommended improvements for hydropower and irrigation of various types of sedimentation tanks. During the study, it was revealed that optimising the geometry of the sedimentation tank significantly increases the efficiency of solid particle deposition. Experimental data have shown that changing the angle of inclination of the walls and increasing the area of the bottom of the sedimentation tank contribute to improving the deposition of silt and sand. It has also been found that the use of special turbulent inserts reduces the particle deposition time and improves the quality of treated water. Hydraulic flow modelling has confirmed that a more uniform velocity distribution in the sedimentation tank reduces turbulence and promotes more efficient particle deposition. The introduction of automated systems for monitoring and controlling the cleaning process has made it possible to increase the reliability and stability of the sedimentation tank. As a result, it was proved that the proposed design and technological changes can significantly increase the efficiency and durability of sedimentation tanks in hydropower and irrigation. The study provides practical recommendations for improving the design of sedimentation tanks, which helps to increase their efficiency and reliability in hydropower and irrigation, thereby improving water management

ELOVL5 and VLDLR synergistically affect n-3 PUFA deposition in eggs of different chicken breeds

There was no significant difference in the composition and content of fatty acids in eggs among different breeds initially, but following the supplementation of flaxseed oil, Dwarf Layer were observed to deposit more n-3 polyunsaturated fatty acid (PUFA) in eggs. Currently, there is limited research on the mechanisms underlying the differences in egg composition among different breeds. Therefore, in this study, 150 twenty-four-wk-old hens of each breed, including the Dwarf Layer and White Leghorn, were fed either a basal diet or a diet supplemented with 2.5% flaxseed oil. After 28 d, eggs and liver samples were collected to determine fatty acid composition, and serum, liver, intestine, and follicles were collected for subsequent biochemical, intestinal morphology, and lipid metabolism-related genes expression analysis. Duodenal contents were collected for microbial analysis. The results showed that there was no significant difference in the content and deposition efficiency of total n-3 PUFA in the liver of the 2 breeds, but the content and deposition efficiency of total n-3 PUFA in the egg of Dwarf Layer were significantly higher than those of White Leghorn after feeding flaxseed oil. Flaxseed oil and breeds did not have significant effects on cholesterol (CHO), free fatty acids (NEFA), low-density lipoprotein (LDL), and estrogen (E2) levels. After feeding with flaxseed oil, the villus height and the villus-to-crypt ratio in both breeds were increased and duodenal crypt depth was decreased. The villus-to-crypt ratio (4.78 vs. 3.60) in the duodenum of Dwarf Layer was significantly higher than that in White Leghorn after feeding with flaxseed oil. Flaxseed oil can impact the gut microbiota in the duodenum and reduce the microbiota associated with fatty acid breakdown, such as Romboutsia, Subdolibranulum, Lachnochlostridium, and Clostridium. This may mean that less ALA can be decomposed and more ALA can be absorbed into the body. Additionally, after feeding flaxseed oil, the mRNA levels of elongation enzymes 5 (ELOVL5), fatty acid desaturase 1 (FADS1), and fatty acid transporter 1 (FATP1) in the liver of Dwarf Layer were significantly higher than those in White Leghorn, while the mRNA levels of peroxisome proliferator-activated receptor alpha (PPAR), carnitine palmitoyl transferase 1 (CPT1), Acyl CoA oxidase 1 (ACOX1), and Acyl-CoA synthetase (ACSL) were significantly lower than those in White Leghorn. The mRNA level of FABP1 in the duodenum of Dwarf Layer was significantly higher than that of White Leghorn, while the mRNA level of FATP1 was significantly lower than that of White Leghorn. The protein levels of ELOVL5 in the liver of Dwarf Layer and very low-density lipoprotein receptor (VLDLR) in the follicles were significantly higher than those of White Leghorn. In summary, after feeding flaxseed oil, the higher ratio of villus height to crypt depth in Dwarf Layer allows more α-linolenic acid (ALA) to be absorbed into the body. The higher mRNA expression of FADS1, ELOVL5, and FATP1, as well as the higher protein expression of ELOVL5 in the liver of Dwarf Layer enhance the conversion of ALA into DHA. The higher protein expression of VLDLR in follicles of Dwarf Layer allows more n-3 PUFA to deposit in the follicles. These combined factors contribute to the Dwarf Layer's ability to deposit higher levels of n-3 PUFA in eggs, as well as improving the deposition efficiency of n-3 PUFA.

Process parameters for enhanced microstructure and composition of as-sprayed Yb2Si2O7 environmental barrier coatings via atmospheric plasma spray

Achieving high crystallinity levels, dense, crack-free microstructures with near-stoichiometric phase composition and controlled secondary phase formation are crucial for enhancing the performance of environmental barrier coatings (EBCs). To investigate the impact of APS process parameters on the as-sprayed crystallinity, microstructure, and phase composition of Yb2Si2O7 EBCs, various spraying conditions were explored by adjusting torch power, nozzle size, powder feedrate, stand-off distance, and adding a shroud attachment to the torch. The velocity of particles controlled the density of the EBCs by an interplay between deposition efficiency and splat flattening ratios. Increasing nozzle size from 5/16″ to 1/2″ reduced particle velocity by up to 40 %, resulting in improved deposition efficiencies, porosity levels and coating thickness. However, larger nozzles led to higher silicon evaporation and up to 8 wt% more stable Yb2SiO5 (I2/a) secondary phase was formed. Increasing the stand-off distance from 50 mm had minimal effect on microstructure, but metastable Yb2SiO5 (P21/c) was detected (up to 9 wt%) at longer stand-off distances of 100 and 150 mm. Raising the powder feedrate from 15 gr/min to 60 gr/min improved deposition efficiency (up to 9 %) and density (up to 15 %) of EBCs, yet resulted in higher silicon-depleted phase formation (up to 12 wt%). Adding a shroud to the torch nozzle exit led to severe silicon evaporation and formation of up to 42 wt% and 6 wt% of Yb2SiO5 (I2/a) and Yb2O3, respectively. Moreover, due to the shroud's funnelling effect on smaller particles as well as particle overheating, porous microstructures with up to 28 % porosity levels were formed. High levels of crystallinity (∼75–91 %) were achieved in the as-sprayed condition for all the coatings, indicating real-time crystallization during spraying in all the spraying conditions.

Highly sensitive and specific detection of human papillomavirus type 16 using CRISPR/Cas12a assay coupled with an enhanced single nanoparticle dark-field microscopy imaging technique

Human papillomavirus (HPV) is a prevalent sexually transmitted pathogen associated with cervical cancer. Detecting high-risk HPV (hr-HPV) infections is crucial for cervical cancer prevention, particularly in resource-limited settings. Here, we present a highly sensitive and specific sensor for HPV-16 detection based on CRISPR/Cas12a coupled with enhanced single nanoparticle dark-field microscopy (DFM) imaging techniques. Ag–Au satellites were assembled through the hybridization of AgNPs-based spherical nucleic acid (Ag-SNA) and AuNPs-based spherical nucleic acid (Au-SNA), and their disassembly upon target-mediated cleavage by the Cas12a protein was monitored using DFM for HPV-16 quantification. To enhance the cleavage efficiency and detection sensitivity, the composition of the ssDNA sequences on Ag-SNA and Au-SNA was optimized. Additionally, we explored using the SynSed technique (synergistic sedimentation of Brownian motion suppression and dehydration transfer) as an alternative particle transfer method in DFM imaging to traditional electrostatic deposition. This addresses the issue of inconsistent deposition efficiency of Ag–Au satellites and their disassembly due to their size and charge differences. The sensor achieved a remarkable limit of detection (LOD) of 10 fM, lowered by 9-fold compared to traditional electrostatic deposition methods. Clinical testing in DNA extractions from 10 human cervical swabs demonstrated significant response differences between the positive and negative samples. Our sensor offers a promising solution for sensitive and specific HPV-16 detection, with implications for cancer screening and management.