Diluent Concentration Research Articles

Effect of diluent content and H2/CO ratio on the laminar combustion characteristics of syngas

A constant volume combustion chamber is employed to investigate the laminar burning characteristics of syngas. The effects of changes in diluent gas composition (CO2/N2) and H2/CO ratio on the laminar burning velocity (SL) of syngas are decoupled and analyzed. The instability of laminar flames is analyzed using effective Lewis number, flame thickness, thermal expansion ratio, and linear stability theory. The results indicate that as the amount of diluent gas increases, thermal diffusion instability (TD) increases, while hydrodynamic instability (DL) gradually decreases. With a decrease in the H2/CO ratio, TD gradually decreases, and DL increases. When the diluent content is below 45%, the critical flame radius under N2 dilution conditions exceeds that under CO2 dilution conditions. Above 45%, the situation reverses. As the H2/CO ratio decreases, the critical flame radius gradually increases. When the H2 content is high, the critical flame radius under N2 dilution conditions is larger.

(Invited) Modeling of the Electric Double Layer (EDL) Structures of Localized High-Concentration Electrolytes (LHCE)

Various electrical double layer (EDL) models have been proposed but mainly for homogenous solutions. Recently, the so-called Localized high-concentration electrolytes (LHCE) have shown many benefits to high-capacity electrodes. Recently, we have proposed micelle-like structures to enable a complete understanding of microstructures in LHCE, which contains a salt, solvent, and non-ion-solvating diluent, analogical to the roles of oil, surfactant, and water as in micelles. [1] As the solid electrolyte interphase (SEI) formation is sensitive to the EDL structure, [2] it is critical to understand the EDL structures for LHCE with heterogeneous structures.Molecular dynamics simulations were performed in several electrolytes with heterogeneous structures on negatively charged surfaces. It was found the Stern model with an absorbed cation layer adsorption layer and a more diffused layer with cation, anion, solvent, and diluents, should be used to describe the EDL of this type of electrolyte.For the system consisting of LiFSI salt, DME solvent, and TFEO diluent at a concentration of LiFSI-1.2DME-2TFEO, the heterogeneous micelle-like structures in LHCE are maintained in the EDL, with the Li+-rich salt-solvent clusters and the Li+-poor diluent regions. The diluent region contains Li+ near the negatively charged surface but does not have any ions in the bulk of LHCE. This is because TFEO cannot form a complete solvation shell in the bulk electrolyte due to the steric effect, however, only a partial solvation shell is needed in the Stern layer in the EDL. The appearance of Li+ in the diluent is also necessary for the EDL, as TFEO alone cannot screen the charge.The chemical and concentration design space for the three components is very large. To obtain a more general picture, we also explored different salt-solvent ratios and different diluent-salt interactions. As the salt solvent ratio increases from low (LCE), to medium (MCE) to high concentration electrolytes (HCE), where all solvents are coordinated with ions, the salt-solvent structures evolve from fully solvated ions or ion pairs in LCE, 3D branched networks in MCE, to fully connected salt aggregates in HCE. The salt-diluent interactions and diluent concentration further modify the micelle-like structures. The EDL for both LHCE and LMCE are heterogenous. [1] Nature Materials 22, 1531–1539 (2023)[2] J. Am. Chem. Soc. 145, 4, 2473–2484 (2023)

Effects of concentrated CO2 on the performance of a PBI/H3PO4 high temperature proton exchange membrane fuel cell

In this study, the impact of mimic reformate of formic acid decomposition on the anode polarization of HT-PEMFC is investigated under various operating conditions of the anode, including different concentrations of CO2, N2, CO, and humidification. Polarization curve and EIS measurements indicate that there is no significant difference (less than 5 mV when i < 0.4A/cm2) between the same concentrations of CO2 and N2 up to 75 vol%. No significant poisoning of the anode by CO2 (up to 75 vol%) has been observed, suggesting that the addition of concentrated CO2 acts more as a diluent than a poison. Upon separating the polarization effects, it is found that the oxygen reduction reaction (ORR) is a crucial step limiting the fuel cell performance, with cathodic activation losses reaching as high as 70 % at 0.8A/cm2. However, with 1 vol% CO in a H2/CO2 1/1 mixture, a significant poisoning effect on the fuel cell is observed. DRT (distribution of relaxation times) analyses reveal two peaks related to CO in high-frequency regions above 100 Hz associated with the anode polarization, with the peak integration being five times larger than in pure hydrogen. Humidification doesn't improve the voltage or mitigate CO poisoning. A one-dimensional flux model that includes the anode polarization is developed to analyze the polarizations for both cathode and anode under different concentrations of diluents, well describing the experimental results. When i < 0.8 A/cm2, the predicted values from the model closely match the measured values (within 5–10 mV). Calculations suggest that the anode polarization cannot be ignored, especially when the anode is fed with diluted gases.

A strategy for selective extraction of lanthanides based on self-assembly with MPyEDChDGA from nitric acid solution☆

The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements. In this paper, the extractant (N,N-methylpyridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide, MPyEDChDGA) with a new structure was synthesized, and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure. Using MPyEDChDGA for efficient enrichment of rare earth ions, the self-assembled solids were recovered by simple filtration without further back-extraction and final precipitation, achieving a one-step strategy for the recovery of rare earth ions. Several important parameters affecting the self-assembly extraction, including pH, diluent, temperature, and extractant concentration, were systematically evaluated using La(NO3)3, Tb(NO3)3, and Lu(NO3)3 as representatives. The self-assembled solids were investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), 1H nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FT-IR), Raman, and X-ray photoelectron spectroscopy (XPS) analyses. The stoichiometry of the extraction species was characterized using the Job’s method and electrospray ionization mass spectrometry (ESI-MS). In addition, MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid, and the results show that MPyEDChDGA has good selectivity of Sm from transition metals (Co, Cu). The separation factor of Sm/Co can reach 6281±117, which provides a new approach to recovering Sm from SmCoCu scrap magnets. This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.

The effect of different active diluents on the properties of epoxy materials

Abstract Epoxy resin is widely used in the insulation packaging field of electrical equipment due to its advantages such as low cost, excellent insulation, and mechanical properties. However, the thermal conductivity and the heat resistance of domestic epoxy insulation packaging materials make it difficult to meet the increasingly demanding operating conditions of electrical equipment. This article investigated the effects of active diluents with different functional group numbers on the glass transition temperature, mechanical strength, and low-temperature cracking resistance of epoxy materials. Four functional group active diluents were selected as additives to reduce the viscosity of epoxy resin, and the influence of diluent content on the comprehensive performance of epoxy resin was studied and analyzed.

Laboratory evaluation of cutback bitumen modified with cup lump rubber

Abstract This research introduces a novel approach to addressing challenges in conventional asphalt used for road construction by incorporating cup lump rubber into cutback bitumen. The study investigates the viscosity and flash point of the resulting cutback bitumen to identify the optimal solvent percentage for achieving a lower mixing and compacting temperature range. Various diluent percentages were tested, ranging from 40% to 50%, across temperatures from 30°C to 70°C. Results indicate that higher diluent percentages lead to decreased viscosity in the blended bitumen. The most efficient solvent content for producing cutback bitumen-modified cup lump rubber is identified at 45% and 50% by weight of the bitumen, offering a reduced mixing and compaction temperature range. However, higher diluent content increases volatility potential and reduces the flash point. Additionally, toxicity testing reveals that lead and zinc are consistently present in cup lump rubber-infused samples, albeit below hazardous waste limits set by TCLP. The absence of lead in unmodified cutback bitumen underscores its compliance with environmental safety standards. These findings underscore the minimal environmental impact of this innovative modified bitumen formulation.

Abstract 307: Generation and characterization of a glioblastoma stem cell model with acquired resistance to LSD1 inhibition

Abstract Epigenetic modifications play an important role in the initiation of various cancer types, including glioblastoma (GBM), and in the development of therapeutic resistance. Patients with GBM, a common malignant brain tumor, have an average survival of 12-15 months after first-line therapy. Lysine-specific demethylase 1 (LSD1) is a histone demethylase that is overexpressed in glioblastoma stem cells (GSCs) and functions to promote proliferation, inhibit differentiation, and enhance motility. Previous work from our group has investigated LSD1 as a therapeutic target in glioblastoma and identified genes that may predict resistance to pharmacological LSD1 inhibitors using RNA-seq. Five upregulated genes, HKDC1, RAB3IL1, RAB39B, FTH1, and FAM213A, were associated with LSD1 inhibitor (LSD1i) resistance and were validated in brain tissue of a GBM model treated with GSK-LSD1 after succumbing to tumor burden. In order to determine whether selection pressure from LSD1 inhibitor treatment caused upregulation of these genes, we created a model of acquired resistance in GSC lines in vitro. Isogenic resistant lines were generated by treating MDA-GSC17 cells with increasing concentrations of LSD1i or diluent (DMSO), as tolerated starting at 50 uM (which was five fold below the IC50 for these lines). In parallel, MDA-GSC17 controls were exposed to DMSO. The resistant line was created over 4 weeks and monitored by cell number and viability to reach 90%. To assess the change in gene expression, we conducted quantitative PCR for the five genes in the parental and resistant MDA-GSC17 line and saw upregulation in 3 of the 5 genes. Two genes, HKDC1 and RAB3IL1, were unable to be assessed due to low basal expression. However, 3 genes were upregulated which are RAB39B, FTH1, and FAM213A. RAB39B is a Ras-analog in brain (RAB) small GTPase and a member of the RAS oncogene family, involved in vesicular trafficking. High expression of ferritin heavy chain 1 (FTH1) is correlated with high-grade gliomas and poor prognosis in glioblastoma. Lastly, the redox regulatory protein, FAM213A, can activate antioxidant proteins and elevated expression is associated with worse outcomes for AML patients. This suggests that modulating the RAS signaling pathways and specific redox pathways may overcome LSD1 resistance. Understanding the changes in gene expression as the cells acquire resistance to LSD1 inhibitors will help us understand the mechanism of resistance to LSD1 inhibitors in glioblastoma and to design new treatment strategies. Citation Format: Kareena H. Patel, Lea Stitzlein, Deokhwa Nam, Frederick Lang, Joy Gumin, Joya Chandra. Generation and characterization of a glioblastoma stem cell model with acquired resistance to LSD1 inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 307.

Competing Influences of Cooling Rate and Diluent Concentration on Crystallization of Poly(3-hexylthiophene)

Competing Influences of Cooling Rate and Diluent Concentration on Crystallization of Poly(3-hexylthiophene)

Effects of reactive diluent on processing, structure, and properties of epoxy foams and their sandwich composites

AbstractFoam sandwich composite (FSC) has recently been widely used in transportation, aerospace, shipping, and construction because of its lightweight, high specific strength, stiffness, and fatigue resistance characteristics. This study aimed to prepare, characterize, and test FSC with different diluent addition amounts. Benzyl glycidyl ester was added to the epoxy foam (EF) as a reactive diluent. Then, the EF was introduced into the three‐dimensional hollow composite (3DHC) by vacuum introduction process to prepare the FSC. Fourier transform infrared spectroscopy and thermogravimetric analysis demonstrated that increased diluent content enhanced SiN bond formation, augmenting thermal stability in resin molecules. The effects of different diluents on the mechanical properties of FSC showed that the mechanical properties of FSC were the best when the diluent content was 5 wt%. Compared with 3DHC, the flat compressive strength, flat tensile strength, and shear strength were increased by 7.2, 6.4, and 2.9 times, respectively.Highlights Diluent improves foaming agent dispersion by lowering resin viscosity. Diluent makes the EP easier to be introduced into 3DHC. FSC demonstrates a 723% increase in flat compression strength.

Influence of Dilution on the Mechanical Properties and Microstructure of Polyurethane-Cement Based Composite Surface Coating.

Polyurethane-cement composite are widely used in modern civil engineering, and the method of adding diluent is often used to adjust the construction process to adapt to the engineering environment. Studies have shown that the addition of diluent impacts the performance of polyurethane-cement based composite surface coatings, but there have been few reports on the influence of diluent content on the mechanical properties and microstructure of the coatings. To address this, polyurethane coatings with different diluent contents were prepared, and positron annihilation lifetime spectroscopy was used to test the microstructure of the coatings. The tensile strength and elongation at rupture were tested using a universal material testing machine, and the fracture interface morphology of each coating was observed by scanning electron microscopy. Finally, the correlation between the microstructure parameters and the mechanical properties of the coating was analyzed using grey relation theory. The results demonstrated that with the increase in diluent content, (i) the average radius of the free volume hole (R) and the free volume fraction (FV) of the coating both showed a trend of first decreasing and then increasing. The value of R was between 3.04 and 3.24 Å, and the value of FV was between 2.08 and 2.84%. (ii) The tensile strength of the coating increased first and then decreased, while the elongation at rupture decreased first and then increased. Among them, the value of tensile strength was between 3.23 and 4.02 MPa, and the value of elongation at fracture was between 49.34 and 63.04%. In addition, the free volume in polymers plays a crucial role in facilitating the migration of molecular chain segments and is closely related to the macroscopic mechanical properties of polymers. A correlation analysis showed that the R value of the coating had the greatest influence on its tensile strength, while FV showed a higher correlation with the elongation at rupture.

Elimination of rare earth (neodymium (III)) from water by emulsion liquid membrane process using D2EHPA as a carrier in kerosene

The present paper highlights the process for the purification of water, which contains Neodymium (III).The applicability of the Liquid Surfactant Membrane (LSM) process for the removal and the concentration of Nd (III) was investigated. The LSM consists of di-(2-ethylhexyl) phosphoric acid as a carrier, commercial kerosene as an organic solvent, span 80 as an emulsifying agent, and sulphuric acid as a stripping phase. The important factors studied which affect the removal Nd (III) are the concentrations of surfactant (1–9% w/w), carrier (0.05–0.9% w/w), internal phase (0.05–1 N H2SO4), pH of feed solution, stirring speed (100 −400 rpm), external phase concentration and type of diluent. The results showed that it is possible to remove 95% of Nd (III) after 15 min contact time by using ELM at the optimum operating conditions. The application of this new membrane matrix based on sulphuric acid used as inner phase, sorbitan monooleate as a surfactant, and D2EHPA as an extractant in kerosene as a diluent has been proven effective for extracting Neodymium (III) ions in water.

In‐plane and in‐depth frontal polymerization behaviors of continuous fiber‐reinforced epoxy composites

AbstractFrontal polymerization (FP) is a self‐sustaining reaction that relies on polymerization exothermicity and heat transfer. This study explores the in‐plane and in‐depth FP mechanisms of continuous fiber‐reinforced epoxy composites. First, the effects of initiator and diluent concentrations on the FP behaviors of neat epoxy resins were examined. It was found that the frontal velocity and frontal temperature of the neat resins increase with an increase of either the initiator concentration or the diluent content, depending on the polymerization enthalpy and curing kinetics. Then, the FP behaviors of continuous carbon fiber and glass fiber‐reinforced epoxy woven composites were investigated. The results showed that the in‐plane FP behavior of the composites was primarily controlled by the thermal conductivity and specific heat capacity of the continuous fibers, whereas the in‐depth FP behavior mainly depended on the pores of the woven fabrics.Highlights Frontal velocity and temperature of neat resins are controlled by the polymerization enthalpy and curing kinetics. The in‐plane FP behavior of continuous fiber reinforced composites is dependent on the thermal conductivity and specific heat capacity of the fibers. The in‐depth FP behavior of composite is determined by both the thermal conductivity of fibers and the pores of fabrics.

Density and viscosity of multicomponent diluent/bitumen mixtures with application to in-situ bitumen recovery and diluted bitumen transportation

The extraction of bitumen relies on energy-intensive methods, and its transportation necessitates dilution due to its high viscosity. Hence, there is a growing demand to explore alternative approaches that are cost-effective and energy-efficient to enhance the extraction and transportation processes. While there is ample thermophysical data available in the literature regarding the individual performance of pure solvents and bitumen systems, there is a significant gap in data concerning density and viscosity measurements for multicomponent solvents and their interaction with bitumen. This study presents new measurements by investigating the effect of varying multicomponent diluent concentrations (7 to 70 wt%) on the density and viscosity of multicomponent diluent/Mackay River bitumen system in a pressure range of 1.291–8.769 MPa and a temperature range of 295–389 K. These thermophysical data are essential in the design, optimization, and reservoir simulation of solvent-based and solvent-aided recovery processes, as well as the surface processing and transportation of diluted bitumen. The findings demonstrated that the addition of the diluent, even at a lower mole fraction, has a notable impact on reducing both the density and viscosity of the bitumen. As part of this study, we have also obtained empirical correlations based on well-established relationships that can be employed as predictive tools for estimating the density and viscosity of a multicomponent diluent/bitumen system. The obtained correlations estimate the density and viscosity of mixtures of bitumen and diluent with average absolute relative deviations (AARD) of 0.4 % and 16.29 %, respectively. The new experimental data are then used to perform zeroth-order energy, greenhouse gas emission, and carbon tax recovery analyses of solvent-aided viscosity reduction. The results reveal that the utilization of natural gas condensate as a diluent leads to significant energy reductions and greenhouse gas emissions. The results find applications in solvent-based and solvent-aided bitumen recovery processes, surface processing, and the transportation of diluted bitumen.

Study of the Rheological Properties and Flow Process of High-Viscosity Oil Using Depressant Additives

This article analyzes the dependence of the choice of the method of transportation of high-viscosity oil on the rheological characteristics of the oil in question. An analysis of existing rheological models of high-viscosity oil was carried out, and it was found that a number of models have certain features (model coefficients, their purpose, quantity) that affect the choice of a rheological model of oil. The dependences for determining the coefficient of dynamic viscosity when pumping high-viscosity oil with the addition of pour-point depressants were studied, and the dependence of the hydraulic resistance coefficient when depressants are added to the oil was obtained. A method for choosing a rational oil heating temperature and diluent concentration to achieve the maximum pipeline performance is substantiated.

The Relationship between Ionic Conductivity and Solvation Structures of Localized High-Concentration Fluorinated Electrolytes for Lithium-Ion Batteries.

Localized high-concentration electrolytes (LHCEs) combine a diluent with a high-concentration electrolyte, offering promising properties. The ions, solvent, and diluent interact to form complex heterogeneous liquid structures, where high salt concentration clusters are embedded in the diluent. Optimizing LHCEs for desired electrolyte properties like high ionic conductivity, low viscosity, and effective solid electrolyte interphase (SEI) formation ability within the vast chemical and compositional design space requires deeper understanding and theoretical guidance. We investigated the structures and conductivities of LHCEs based on a fluorinated solvent with two different diluents at varying concentrations. 2,2,3,3-Tetrafluoropropyl trifluoroacetate (TFPTFA) enters the solvation cluster due to its stronger Li-ion interactions, whereas 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether (TFETFE) enters only at extremely high diluent concentrations. The ionic conductivity increases with decreasing diluent concentrations, with a slope change during cluster percolation. Overall, TFETFE demonstrates higher effectiveness than TFPTFA, forming higher local salt concentration clusters and resulting in higher ionic conductivity.

UV-Curing Additive Manufacturing of Bio-Based Thermosets: Effect of Diluent Concentration on Printing and Material Properties of Itaconic Acid-Based Materials.

In the quest toward sustainable thermosets, research has been conducted on various polymer classes like epoxy, benzoxazines, acryl-/methacrylates, etc. One particular group that can also be utilized as sustainable inks for additive manufacturing is itaconic acid-based unsaturated polyester resins. However, due to increased viscosity of the resins, the use of reactive diluents is required to increase their processability. While research has focused on creating different polymeric structures to expand the possible applications, the required amount of diluent has not received equal attention. In this work, a group of itaconic acid-based polyesters was synthesized to create a series of formulations with different reactive diluent contents. The physicochemical properties of the prepared formulations, along with their reactivity toward UV light, were assessed via photo-differential scanning calorimetry (photo-DSC), real-time attenuated total reflectance (RT-ATR), and photorheology measurements. The same formulations were then used to fabricate test specimens via digital light processing (DLP) three-dimensional (3D) printing, which were examined as to their thermomechanical properties by means of dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) measurements.

STUDY OF WAYS TO REDUCE THE VISCOSITY OF SUNFLOWER LECITHIN

Today, lecithin is the most important by-product of oilseed processing due to its numerous technological properties. Food industry technologists use lecithin as an emulsifier, wetting agent, stabilizer, viscosity regulator, crystal formation, etc. One of the main disadvantages of sunflower lecithin is the tendency to increase viscosity (plasticization) during storage. Such lecithin is difficult to use. Therefore, obtaining liquid lecithin with a viscosity of less than 12 Pa s (at 25 °C), which does not increase during its storage, is one of the urgent tasks of enterprises for the extraction and processing of vegetable fats. The article compares diluents of different types. Diluents of fatty nature - sunflower oil, oleic acid and its ethyl ester are characterized by a significantly lower viscosity compared to lecithin, therefore they can act as diluents that do not affect the quality of lecithin. However, their amounts are too large to achieve the goal of obtaining liquid lecithin. These amounts significantly reduce the "acetone insoluble" lecithin index. That is, oils, their acids and esters cannot be recommended for reducing the viscosity of lecithins in industry. It has been shown that the efficiency of divalent calcium salts as diluents is much greater, even at low concentrations of these substances. It has also been proven that the introduction of diluents must be carried out before the stage of drying the wet gum. To obtain liquid lecithin from plasticized lecithin, approximately twice as high concentrations of diluents are required compared to the preventive approach - the introduction of diluents into a wet gum. To obtain liquid sunflower lecithin from a wert gum to which diluents were added, the effective concentrations of diluents are as follows,%: sunflower oil - 13, oleic acid - 5, ethyl ester of oleic acid - 4, calcium chloride - 0.35, calcium acetate - 0.4, calcium orthophosphate - 0.4, concentrated phosphoric acid - 2. It is most expedient to use calcium salts in order to obtain high quality liquid lecithin.

Preparation of Hyflon AD/Polypropylene Blend Membrane for Artificial Lung.

A high-performance polypropylene hollow fiber membrane (PP-HFM) was prepared by using a binary environmentally friendly solvent of polypropylene as the raw material, adopting the thermally induced phase separation (TIPS) method, and adjusting the raw material ratio. The binary diluents were soybean oil (SO) and acetyl tributyl citrate (ATBC). The suitable SO/ATBC ratio of 7/3 was based on the size change of the L-L phase separation region in PP-SO/ATBC thermodynamic phase diagram. Through the characterization and comparison of the basic performance of PP-HFMs, it was found that with the increase of the diluent content in the raw materials, the micropores of outer surface of the PP-HFM became larger, and the cross section showed a sponge-like pore structure. The fluoropolymer, Hyflon ADx, was deposited on the outer surface of the hollow fiber membrane using a physical modification method of solution dipping. After modification, the surface pore size of the Hyflon AD40L modified membranes decreased; the contact angle increased to around 107°; the surface energy decreased to 17 mN·m-1; and the surface roughness decreased to 17 nm. Hyflon AD40L/PP-HFMs also had more water resistance properties from the variation of wetting curve. For biocompatibility of the membrane, the adsorption capacity of the modified PP membrane for albumin decreased from approximately 1.2 mg·cm-2 to 1.0 mg·cm-2, and the adsorption of platelets decreased under fluorescence microscopy. The decrease in blood cells and protein adsorption in the blood prolonged the clotting time. In addition, the hemolysis rate of modified PP membrane was reduced to within the standard of 5%, and the cell survival rate of its precipitate was above 100%, which also indicated the excellent biocompatibility of fluoropolymer modified membrane. The improvement of hydrophobicity and blood compatibility makes Hyflon AD/PP-HFMs have the potential for application in membrane oxygenators.

Effect of reactive diluent concentration on rheological and curing behavior of zirconia ceramic slurry for DLP printing

AbstractA series of photosensitive zirconia ceramic slurry with adjustable viscosity and cured depth have been presented for the construction of high‐quality zirconia ceramic fabricated by digital light processing 3D printing. The rheological and curing behavior of the slurry can be flexibly optimized by tuning the reactive diluent concentration and category, since the change of dominant position of diluent on viscosity and the different curing mode. Monofunctional reactive diluent (HEA, hydroxyethyl acrylate) exhibits an enhanced dilution effect compared with that of bifunctional reactive diluent (HDDA, 1,6‐hexamethylene diacrylate) due to the lower molecular mass of monofunctional diluent. As a result, the viscosity reaches lower than 2000 mPa·s when the concentration of both HEA and HDDA exceeds 50 wt.%. At the same time, the non‐Newtonian properties of the slurry are also changed, which facilitates the printing process. However, excessive addition of diluent may generate more defects in ceramic green body. Consequently, the cured depth of zirconia slurry can reach 55 and 50 µm, respectively, at the curing time of 3 s while introducing the HEA or HDDA with the concentration below 70 wt.%, and the modified feedstock is promising for high‐quality and low‐defect zirconia ceramic components printing for biomedical applications.

Research on Detection of Ultra-Low Concentration Anthrax Protective Antigen Using Graphene Field-Effect Transistor Biosensor.

Protective antigen (PA) is an important biomarker for the early diagnosis of anthrax, and the accurate detection of protective antigen under extremely low concentration conditions has always been a hot topic in the biomedical field. To complete the diagnosis of anthrax in a timely manner, it is necessary to detect PA at extremely low concentrations, as the amount of PA produced in the early stage of anthrax invasion is relatively small. Graphene field-effect transistor (Gr-FET) biosensors are a new type of material for preparing biosensors, with the advantages of a short detection time and ultra-low detection limit. The effect of different concentrations of diluents on the affinity of PA monoclonal antibodies was determined via an ELISA experiment. Combined with the Debye equation, 0.01 × PBS solution was finally selected as the diluent for the experiment. Then, a PA monoclonal antibody was selected as the bio-recognition element to construct a Gr-FET device based on CVD-grown graphene, which was used to detect the concentration of PA while recording the response time, linear range, detection limit, and other parameters. The experimental results showed that the biosensor could quickly detect PA, with a linear range of 10 fg/mL to 100 pg/mL and a detection limit of 10 fg/mL. In addition, the biosensor showed excellent specificity and repeatability. By constructing a Gr-FET device based on CVD-grown graphene and selecting a PA monoclonal antibody as the bio-recognition element, a highly sensitive, specific, and repeatable Gr-FET biosensor was successfully prepared for detecting extremely low concentrations of anthrax protective antigen (PA). This biosensor is expected to have a wide range of applications in clinical medicine and biological safety monitoring.