Viscosity Temperature Research Articles

Introducing an integrated self-organizing map and radial basis function network for accurate prediction of water- Fe3O4 nanofluid viscosity versus solid volume fraction and temperature

Nanofluids, colloidal suspensions of nanoparticles in base fluids, promise improved thermal conductivity and energy efficiency. Predicting nanofluid viscosity, influenced by factors like temperature and nanoparticle concentration, is crucial for optimizing performance. This research introduces an innovative approach combining Self-Organizing Map (SOM) and Radial Basis Function (RBF) networks to accurately predict viscosity. The SOM guides RBF center placement for enhanced accuracy, validated with water-Fe3O4 nanofluid data. Temperature significantly affects viscosity, with adjustments from 10 to 50 °C showing viscosity decreases from around 5 to lower than 2 mPa.s. The integrated SOM-RBF model achieves high precision (max absolute error 0.1078 mPa.s, 4 % relative error), suggesting potential for further enhancement. This novel neural network combination enhances efficiency in nanofluid applications, advancing predictive modeling in nanofluid engineering for broader industrial and scientific innovation.

Transfer learning for accurate description of atomic transport in Al-Cu melts.

Machine learning interatomic potentials (MLIPs) provide an optimal balance between accuracy and computational efficiency and allow studying problems that are hardly solvable by traditional methods. For metallic alloys, MLIPs are typically developed based on density functional theory with generalized gradient approximation (GGA) for the exchange-correlation functional. However, recent studies have shown that this standard protocol can be inaccurate for calculating the transport properties or phase diagrams of some metallic alloys. Thus, optimization of the choice of exchange-correlation functional and specific calculation parameters is needed. In this study, we address this issue for Al-Cu alloys, in which standard Perdew-Burke-Ernzerhof (PBE)-based MLIPs cannot accurately calculate the viscosity and melting temperatures at Cu-rich compositions. We have built MLIPs based on different exchange-correlation functionals, including meta-GGA, using a transfer learning strategy, which allows us to reduce the amount of training data by an order of magnitude compared to a standard approach. We show that r2SCAN- and PBEsol-based MLIPs provide much better accuracy in describing thermodynamic and transport properties of Al-Cu alloys. In particular, r2SCAN-based deep machine learning potential allows us to quantitatively reproduce the concentration dependence of dynamic viscosity. Our findings contribute to the development of MLIPs that provide quantum chemical accuracy, which is one of the most challenging problems in modern computational materials science.

Numerical simulation of magnetically driven nanomaterial rotating flow configured by convective-radiative cone with chemical reaction

Indeed, nanoliquids have acquired substantial consideration in heat transference field because of their inimitable thermal attributes and favorable application likelihoods. In contrast to orthodox liquids, the haphazard movement of nanoparticles within nanoliquid strengthens fluid turbulence, accomplishes superior thermal effectiveness and declines thermal resistance. Nanoliquids have ample utilization, for illustration, solar energy, electronic chips, automotive radiators and heat exchangers etc. This communication reports chemically reactive electro-magnetized nanomaterial dissipative flow confined by rotating cone. Flow expressions include thermo-solutal buoyancy, varying viscosity and magneto-hydrodynamics. Radiative heat, thermophoresis, viscous dissipation, Brownian diffusion, thermal source and first order chemical reaction are pondered to model transport expressions. Relevant variables are introduced to transfigure partial differential mathematical expressions to mathematical ordinary ones. Numerical outcomes for non-dimensional mathematical expressions are reported via bvp4c algorithm in MATLAB. The comprehensive results featuring dimensionless quantities are explored through graphs and arithmetic representations. It is evaluated that escalating values of variable viscosity, Prandtl number and unsteady parameter decline temperature but temperature is improved as a consequence of progressive variation in radiation parameter, Eckert number, thermophoresis parameter, heat generating and Brownian diffusive variables. The study is relevant to cooling industry, electroconductive, thermal collector and nano-materials processing.

Starch digestion and physiochemical properties of a newly developed rice variety with low glycemic index

This study aimed to clarify the starch digestion characteristics and related physicochemical properties of the newly developed low-GI rice variety, Ditangliangyou 335 (D335), in comparison with two widely grown rice varieties, Xiangzaoxian 45 (X45) and Zhongzao 39 (Z39). The results showed that D335 had an active digestion duration (286 min) that was 101–190 % shorter, a glucose production rate (1.06 mg g−1 min−1) that was 57–73 % slower, and a total glucose production (303 mg g−1) that was 11–19 % less than X45 and Z39. These differences were attributable to the distinct starch physicochemical properties, including amylose content, amylose-to-amylopectin ratio, starch granule size, amylopectin chain length, and starch molar mass, as well as the different pasting properties of rice flour, such as pasting temperature and breakdown viscosity. These findings reveal the starch digestion characteristics and the key physicochemical properties that determine these characteristics in the low-GI rice variety D335.

Effects of low temperature on near-nozzle breakup and droplet size distribution in airblast kerosene spray

Atomization of low-temperature fuel is encountered in extreme operating conditions of liquid propulsion systems such as cold start and high-altitude relight for aeroengines. Fuel temperature has a great impact on airblast spray characteristics by influencing fuel viscosity and thus the gas–liquid interaction, which raises the demand to clarify the temperature-dependent transition in near-nozzle breakup behavior and the corresponding droplet size distribution. A liquid-centered swirl coaxial injector is tested on the low-temperature swirl spray and combustion test rig at Zhejiang University, using 25 kHz high-speed digital off-axis holography. RP-3 aviation kerosene is atomized under ignition conditions at temperatures of 233, 253, and 301 K, fuel pressures of 0.03 and 0.69 MPa, and air pressure ranging from 0 to 4.0 kPa. Time-resolved near-nozzle dynamics suggest four types of elementary breakup processes: wavy-sheet breakup, pulsating breakup, membrane-type breakup, and nonaxisymmetric Rayleigh breakup. Each process alternately dominates the near field as fuel Reynolds number (Ref) and aerodynamic Weber number (Weg) decrease, corresponding to four primary breakup modes. A mode classification plot is summarized. Spray structures show an extended breakup length and reduced spray cone angle as fuel temperature (Tf) decreases. Increasing air pressure (Pg) promotes spray expansion at 0.03 MPa, but contracts spray cone at 0.69 MPa. Cross-sectional Sauter mean diameter (SMD) distribution indicates a solid-cone spray at 0.03 MPa and a hollow cone spray at 0.69 MPa. Lowering Tf will rise the SMD in the spray center at 0.03 MPa and transform the toroidal SMD distribution at 0.69 MPa into a solid one. Finally, a temperature-related SMD model is derived considering the exponential viscosity–temperature relationship, and a good fit with R2 > 0.95 is achieved. This research aims to deepen the understanding of the effects of low temperature on the transition of near-nozzle atomization characteristics for airblast sprays. Both spray visualization and SMD results provide reference for numerical simulations and near-nozzle spray modeling.

Study of Li2O reduction in mould slag for continuous casting of low-carbon steel slab

The addition of Li2O increases production costs for continuous casting, despite its enhancement of the melting and flow properties of mould slag. Initially, laboratory research focused on assessing the individual impacts of Li2O, F, Na2O and Al2O3 on the viscosity and melting temperature of the slag, using a basicity of 0.95. Subsequently, four stages of industrial testing were conducted to optimise the slag, evaluating parameters such as temperature and friction force curves of the mould copper plate thermocouple, steel slag consumption per ton and strand surface quality. The optimised slag achieved a basicity of 0.98, a viscosity of 0.29 Pa·s and a melting temperature of 1115 °C, meeting all performance requirements for low-carbon steel mould slag. Compared to the original flux, the mass percentage of Li2O decreased significantly from 1.54 to 0 wt-%, while Na2O increased from 2.36 to 7.35 wt-%, and Al2O3 decreased from 7.28 to 3.49 wt-%. The operation of the optimised flux remained stable, with smooth fluctuations observed in the mould copper plate thermocouple temperature and friction force curves. These research findings hold significant reference and practical value for further development and application.

4D Printing of Ultra‐High Performance Shape Memory Polymer for Space Applications

Developing thermoplastic polyimide (TPI), capable of handling space conditions, through 4D printing is challenging due to its high melting temperature and inherent viscosity. This study presents 4D printing of TPI for shape memory investigation under repetitive cycles for the first time, exploring its potential for self‐deployable hinges in space devices. 4D‐printed TPI exhibits outstanding shape memory effect (SME) with shape fixity (Rf) up to 100% and shape recovery (Rr) of 100% in first cycle. Rf is noted to be increasing up to third cycle and then fixed to 100% up to tenth cycle, while Rr shows a decreasing trend in subsequent cycle with a drop of 37% in tenth cycle. Moreover, it exhibits extremely high glass‐transition temperature, Tg = 263.10 °C, degradation temperature, Td = 520 °C, and storage modulus of 1600 MPa. Among existing high‐performance (HP) and conventional shape memory polymers (SMPs), 3D‐printed TPI exhibits superior performance. Tg of the TPI is found to be 66.52%, 107.16%, and 62.41%, higher than existing HP‐SMPs, polyether ether ketone (Tg = 158 °C), polyamide (Tg = 127 °C), and polyether ketone ketone (Tg = 162 °C), respectively. This investigation reveals a novel characteristic, the SME, of 4D‐printed TPI with ultra‐high Tg and Td, demonstrating suitability for self‐deployable hinges, contributing to materials engineering and 4D printing.

Control of the parameters of thermosetting binders directly during the molding of products made of polymer composite materials

For aviation binders at the moment there is no necessary methodological base on the basis of which it is possible to control the conditions of their curing by viscosity, reaction rate and glass transition temperature in real time. The paper presents a method of control of thermosetting binder parameters directly during the molding process. The epoxy binder VSE-59 was studied. A mathematical model of the relationship between the frequency maximum parameter of the imaginary component of the electrical impedance and the degree of curing is given, the results of dielectric analysis are compared with laboratory methods (differential scanning calorimetry and rheometry). It is shown that the convergence of the values of the degree of conversion is high. Rheological and dielectric analyses revealed a direct correlation between electrical and rheological properties in the range of injection temperatures. Equations were determined and coefficients were experimentally selected to describe the correlation between viscosity and glass transition temperature and dielectric parameters, which provides the possibility of their control in real time. The obtained results can be used to create a hardware and software base, which makes it possible to control the state of the binder at each moment of the process of forming products from polymer composite materials, as well as to carry out optimization to eliminate the emergence of conditions of uneven polymerization. Realization of the detailed control of the binder state in different parts of the product will allow to carry out verification of calculations, to predict and avoid the occurrence of warping and, accordingly, to increase the quality of composite products.

Trialkylsulfonium Thiocyanate Ionic Liquids: Investigation on Temperature‐Dependent Ignition Behavior of Green Hypergolic Propellants

AbstractThree trialkylsulfonium thiocyanate ionic liquids (ILs) are presented as fuel candidates for novel green hypergolic propellants. The physical and chemical properties such as density, viscosity, melting point and decomposition temperature as well as the enthalpy of formation of the ILs were determined. Further, the research focused on the potential of the ILs as fuel components for hypergolic propellants with highly concentrated hydrogen peroxide as oxidizer. For this, the theoretical maximum specific impulses of the propellants were calculated with NASA CEA. To evaluate the ignition delay times of the hypergolic propellants, drop tests were carried out. These were conducted not only at ambient conditions but also at lower levels of fuel temperature. It was found that all three propellant combinations still ignited reliably at temperature levels down to −25°C, however, the average ignition delay increased at lower temperatures. Overall, not only three promising hypergolic fuels were identified, but also important insights into the temperature‐dependent ignition behavior of hypergolic ionic liquid‐based propellants with thiocyanate anions were obtained.

Performance evaluation of bio-oil and high rubber content modified asphalt: More effective waste utilization

In this study, the bio-oil was used to reduce the viscosity and preparation temperature of high content of rubber-modified asphalt. The high rubber content modified bio-asphalt (RMBA) was prepared, the rubber and bio-oil contents were 20 %-30 % and 5 %-15 % (mass ratio of neat asphalt), respectively. The viscosity, temperature sweep (TS), frequency sweep (FS), multi-stress creep recovery (MSCR), and bending beam rheometer (BBR) tests were performed to assess the properties of RMBA. The Fourier Transform infrared spectroscopy (FTIR), Fluorescence microscopy (FM), and Scanning electron microscope (SEM) tests were conducted to explore the microscopic morphology of RMBA. Besides, the economic analysis and life cycle assessment (LCA) were assessed. Bio-oil contributed to the viscosity-reduction of the RMBA. When the rubber content was 30 %, the viscosity decreased by 48.16 % with a bio-oil content of 15 %. The temperature and frequency sensitivity of RMBA were lower than neat asphalt. Rubber improved the creep recovery and anti-rutting deformation behavior for bio-asphalt. The absorption peaks appeared at 1010 and 1038 cm−1, which represented the SO function group. The rubber did not absorb enough bio-oil for solubilization. This resulted in the functional group of SO appeared in 30 %+B-10 % and R-30 %+B-15 %. FM and SEM test results indicated that the rubber in RMBA exists in different states: undissolved rubber and dissolved rubber. The high content rubber could be partially dissolved in bio-asphalt and retained its elastic properties. The dissolved rubber particles exhibited a large crosslinked network structure. The raw material cost of RMBA decreased significantly with the rise of rubber and bio-oil contents. The reasonable application of waste rubber is beneficial to the alleviation of black pollution. The efficient application of rubber and bio-oil could contribute to the development of waste utilization and green transportation.

Spontaneous imbibition of unsaturated sandstone under different vertical temperature gradients: neutron radiography experiments and dynamic models

To elucidate the imbibition behavior of water in complex temperature and stress environments, spontaneous imbibition experiments were conducted on unsaturated matrix sandstones at different vertical temperature gradients by neutron radiography technology. Additionally, corresponding dynamic models of water imbibition in porous media were established. The research results reveal the phased characteristics of sandstone spontaneous imbibition and the influence of vertical temperature gradient on the evolution of wetting front. Specifically, the initial development speed of the wetting front increases with an increase in the vertical temperature gradient, indicating a direct relationship. However, the growth rate of the wetting front gradually slows down with increasing time, eventually reaching a saturated state. Model validation demonstrates that the traditional Washburn's law is still valid in isothermal conditions without temperature gradient (G=0). Further analysis indicates that the imbibition rate has a direct correlation with linear thermal expansion coefficient (α) and viscosity temperature coefficient (β) across various vertical temperature gradients, and an inverse correlation with surface tension temperature coefficient (γ). Furthermore, when the values of α, β, and γ fall below 0.001, their impact on the imbibition rate becomes negligible. The sensitivity of the imbibition rate to parameters γ, β, and α decreases in that order, with γ being the most sensitive, followed by β, and α being the least sensitive. Moreover, the relative importance of α, β, and γ dictates their specific influence on the imbibition rate, and a synergistic effect exists among these parameters, which collectively influence the water absorption behavior of sandstone.

Quantifying the impact of AGN feedback on the large-scale matter distribution using two- and three-point statistics

Abstract Feedback from active galactic nuclei (AGN) plays a critical role in shaping the matter distribution on scales comparable to and larger than individual galaxies. Upcoming surveys such as Euclid and LSST aim to precisely quantify the matter distribution on cosmological scales, making a detailed understanding of AGN feedback effects essential. Hydrodynamical simulations provide an informative framework for studying these effects, in particular by allowing us to vary the parameters that determine the strength of these feedback processes and, consequently, to predict their corresponding impact on the large-scale matter distribution. We use the EAGLE simulations to explore how changes in subgrid viscosity and AGN heating temperature affect the matter distribution, quantified via 2- and 3-point correlation functions, as well as higher order cumulants of the matter distribution. We find that varying viscosity has a small impact ($\approx 10~{{\%}}$) on scales larger than 1h−1 Mpc, while changes to the AGN heating temperature lead to substantial differences, with up to 70% variation in gas clustering on small scales (≲ 1h−1 Mpc). By examining the suppression of the power spectrum as a function of time, we identify the redshift range z = 1.5 − 1 as a key epoch where AGN feedback begins to dominate in these simulations. The 3-point function provides complementary insight to the more familiar 2-point statistics, and shows more pronounced variations between models on the scale of individual haloes. On the other hand, we find that effects on even larger scales are largely comparable.

Development of synergistic antifungal in situ gel of miconazole nitrate loaded microemulsion as a novel approach to treat vaginal candidiasis

Limited solubility is the main cause of the low local availability of anti-candidiasis drug, miconazole nitrate (MN). The study’s objective was to develop and characterize microemulsion (ME) based temperature-triggered in situ gel of MN for intravaginal administration to enhance local availability and antifungal activity. The solubility of MN was initially studied in different oils, surfactants, and co-surfactants. Then, pseudo-ternary phase diagrams were constructed to select the best ratio of various components. The ME formulations were characterized by thermodynamic study, droplet size, polydispersity index (PDI), viscosity, and in-vitro antifungal mean inhibition zone (MIZ). Selected MEs were incorporated into different in situ gel bases using a combination of two thermosensitive polymers (poloxamer (PLX) 407 and 188), with 0.6% of hydroxypropyl methylcellulose (HPMC K4M) and gellan gum (GG) as mucoadhesive polymer. ME-based gels (MG) were investigated for gelation temperature, gelation time, viscosity, spreadability, mucoadhesive strength, in vitro release profile, and MIZ test. Furthermore, the optimum MG was assessed for in vivo animal irritation test and FESEM investigation. Tea tree oil, lavender oil, tween 80, and propylene glycol (PG) were chosen for ME preparation for the optimal formulation; formulation ME7 and ME10 were chosen. After incorporation of the selected formulation into a mixture of P407 and P188 (18:2% w/w) with 0.6% mucoadhesive polymer, the resultant MG formulation (MG1) revealed optimum gelation temperature (33 ± 0.01℃) and appropriate viscosity with enhanced sustained release (98%) and retention through sheep vaginal mucosa, MG1 exhibited a better MIZ compared to the 2% MN gel formulation and the marketed MN product, and no rabbit vagina irritation. In conclusion, the miconazole nitrate-loaded MG-based formula sustained the duration of action and better antifungal activity than the marketed miconazole nitrate formulation.

The Association Between the Structure of the Fatty Chain in Amides and Their Lubricating Performance in Acrylonitrile‐Butadiene‐Styrene (ABS) Resins

ABSTRACTThe exploitation of efficient lubricants for ABS resins is widely recognized as beneficial for industrial production. Fatty diamides are typically applied as the lubricants for ABS resins; however, the connection between fatty chain structures and the lubricating properties is still vague. In this work, a range of ethylenediamine‐based amide lubricants (EDA‐Cn) with different fatty chain structures were successfully prepared and chemical structures were characterized in detail by the Fourier transform infrared spectrometer and proton nuclear magnetic resonance. The rheological test results suggested that the complex viscosity and relaxation time were positively associated with the fatty chain lengths of EDA‐Cn. The dynamic mechanical analysis results confirmed that EDA‐Cn exhibited excellent compatibility with ABS resins. The lubricating effect of EDA‐Cn decreased with increasing fatty chain lengths, which was manifested by a higher glass transition temperature, and lower elongation at break of ABS resins. In comparison to EDA‐C22, the complex viscosity (angular frequency = 0.1 rad/s) and glass transition temperature of EDA‐C10 have decreased by 24.9% and 3.9%, respectively. The molecular dynamics simulations revealed the intrinsic mechanism of lubricant‐substrate interaction. The EDA‐Cn containing short fatty chain lengths reduced the interaction energy with the matrix, thereby promoting the diffusive movement of the chain segments, and resulted in the increase in the mean square displacement and improved flow properties. These findings provided sufficient theoretical basis for the rational design and preparation of lubricants for ABS resins.

Capturing non-equilibrium in hypersonic flows: Insights from a two-temperature model in polyatomic rarefied gases

The study utilizes a two-temperature model to analyze non-equilibrium in normal shocks within hypersonic flows in polyatomic rarefied gases. Derived from the extended second law of thermodynamics, this model separates translational and internal temperatures in polyatomic gases, providing a more accurate depiction of non-equilibrium gas flow compared to classical theories like the Navier–Stokes and Fourier (NSF) system. Notably, the analysis reveals that the two-temperature model incorporates an additional contribution to the heat flux due to the gradient of the dynamic temperature, resulting in improved accuracy, especially for high Mach numbers. Results show that the model gives satisfactory shock density and temperature profiles up to Mach 10, with very good agreement observed up to Mach 6.1 compared to the classical NSF model. We conduct an order of magnitude analysis on the dynamic temperature and heat flux gradients appearing in the new constitutive equation using the Mott-Smith method. This analysis highlights the impact of these terms on accurately modeling polyatomic gas behavior in high-speed flows. The effects of bulk viscosity and incoming temperature on shock profiles are also investigated, contributing to a better understanding of shock wave structures in polyatomic gases and their implications for hypersonic flow dynamics.

Study on the Effect of Nitrogen Bubble Foam Flooding in Deep Heavy Oil Reservoirs with Edge And Bottom Water

Abstract The oil recovery rate is low, the degree of recovery is low and the water content rises fast after water flooding in deep edge and bottom water heavy oil reservoir in Lukeqin oilfield. In order to explore the method to improve the production effect, the integrated foam system of high temperature and high pressure resistant viscosity reduction and oil displacement is optimized. On the basis of clarifying the mechanism of improving the production effect of nitrogen foam flooding for deep heavy oil, taking the west area of Lukeqin oilfield as the research object, the parameter optimization design of nitrogen foam flooding for deep edge and bottom water heavy oil is carried out, such as injection section plug, gas-liquid ratio and injection-recovery ratio. The optimization results are as follows: the injected nitrogen foam slug is 0.2pv, the gas-liquid ratio is 1-1.2, and the injection production ratio is 1:1. The pilot test of 4 well groups was carried out on the site. After foam flooding, the injection pressure was increased by 5.2mpa, the daily oil production of the oil well was increased by 43T / D, the water cut was decreased by 45%, the accumulated oil production was increased by 32000 tons, and the oil recovery was expected to be increased by more than 10%. The purpose of improving the development efficiency of this type of oil reservoir was achieved. Using this optimization technology for scheme design and field implementation, the oil enhancement effect is remarkable and improves the benefit of deep thick oil development, which can provide technical support for the development of similar domestic reservoirs.

Analysis of disturbance factors of magnetorheological damper in continuous impact buffer system

Abstract Magnetorheological (MR) impact buffering systems are widely used in vehicle suspensions, bridge damping, and aircraft landing gear due to their excellent buffering performance and rapid response time. However, under the condition of high-speed continuous impact, magnetorheological damper (MRD) operate in complex environments where various internal and external uncertainties can negatively affect control performance. This paper analyzes the impact of disturbance signals on MR buffering systems and explores control strategies to mitigate these effects. First, we established a hysteresis model based on experimental data and identified parameters using a genetic algorithm to determine the influence of hysteresis disturbances. Next, we developed a temperature model based on the thermal characteristics of SG-MRF2035 magnetorheological fluid, fitting the relationship between temperature and dynamic viscosity to identify temperature disturbances. The results showed that when disturbances were considered, the system exhibited higher peak damping forces and a deviation from the desired ‘platform effect’ in the damping force-displacement relationship. Finally, we applied an Active Disturbance Rejection Control(ADRC) strategy, which effectively compensated for the hysteresis and temperature disturbances, enhancing the system’s robustness. Compared to PID control, the ADRC-controlled system demonstrated lower peak damping forces and a damping force-displacement relationship closer to the desired platform effect.

Synthesis and chemical recycling investigations of polythioureas

There is currently intensive research on the development of biobased polymers as potential alternatives to the environmentally hazardous isocyanate-based polyurethanes. In this context, polythioureas (PTUs) form a particularly attractive target because they can be synthesized by using isothiocyanates, a class of molecules that can be found in nature with expected low toxicity. Herein, a series of 16 PTUs with varied chemical structures, mostly being new polymers, have been synthesized and their possible chemical recycling pathways via thermally induced and acid-catalyzed depolymerizations have been investigated. The obtained PTUs showed a varied range of molecular weights (up to Mn ∼ 69.5 kDa), intrinsic viscosity (up to ∼6 dL/g), and glass transition temperatures (Tg ∼ 59–128 °C). Notably, we observed that the presence of aromatic segments lowered the thermal stability of the polymers, so they were generally easier to depolymerize (compared to those without aromatic groups), forming oligomers with controlled end-groups (i.e. telechelic polymers) that could be repolymerized. The obtained aliphatic PTUs were generally resistant against thermochemical depolymerizations, but they could be effectively depolymerized by sulfuric acid. The repolymerization methods depended on the end groups of the depolymerized products, which in this work included direct repolymerization of polythioureas (if the end groups contain ∼1:1 of isothiocyanates and amines) and copolymerizations with another monomer terephthaldehyde (if the end groups contain only amines). Our results provided a first comprehensive molecular insight into the synthetic and recycling possibilities of using isothiocyanates and polythioureas in the exploration of potential alternatives for isocyanates and polyurethanes.

Direct Printing of Disperse Dye Inks to Polyester Fabrics without Chemical Pretreatment.

Direct inkjet digital printing is a relatively green and environmentally friendly textile printing method with a wide range of applications in the textile printing and dyeing industry. However, pretreatment of the fabric is required before digital printing, which will generate certain energy consumption and wastewater. In this study, a digital direct inkjet printing method was developed to improve the printing accuracy of poly(ethylene terephthalate) (PET) fabrics without any pretreatment. A kind of direct inkjet printing ink was prepared by the response change in temperature viscosity. The increase in viscosity inhibits ink bleeding on the fabric, thereby improving printing accuracy. A thermosensitive direct inkjet printing disperse dye ink was prepared by adding cetyltrimethylammonium bromide (CTAB) and 3-methylsalicylic acid (3MS) to the ink. By evaluating the changes in the ink particle size, shear viscosity, and temperature viscosity, it was found that this thermosensitive ink has an excellent average particle size and special changes in viscosity with increasing temperature. When this heat-sensitive ink is printed on a polyester fabric, the fabric does not need pretreatment to improve the clarity of printing, and the printed fabric has satisfactory color fastness to friction and washing.

The physicochemical, functional, and pasting properties of Moringa oleifera leaf powder from different leaf stalk colors

ABSTRACT Moringa oleifera (MO) leaf powder (MOLP) is functional, and its composition affects its use. The MO tree has different colors i.e. white, green, and red. This study aimed to evaluate MOLP physicochemical, functional, and pasting properties based on the leaf stalk color as the basis for their suitable use in food products. Leaf stalk color slightly affect characteristics, with typical high protein, dietary fiber, and ash, but low starch and fat. MOLP has high soluble dietary fiber, high amylose starch, and significant amounts of phenolics and flavonoids. Chlorophyll is the abundant pigment followed by β carotene. MOLP is rich in essential amino acids with methionine is a limiting essential amino acid. MOLP has almost equal saturated and unsaturated, and rich in essential fatty acids. Low starch and high fiber affect pasting properties, exhibiting low viscosity and gelatinization temperature, but high stability. Low solubility of MOLP is a challenge to improve.