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Site period has been widely acknowledged to be a reasonable site parameter for ground-motion modeling and site effect modeling. Its value could be analytically calculated using the shear-wave velocity (V S) profile by assuming that soil layers overlie a rigid bedrock, or empirically estimated from the horizontal-to-vertical spectral ratio (HVSR). In this study, we tested the uncertainty of site period on the variability of the site period-based ground-motion prediction equations (GMPEs). The ground-motion records and site data in Japan were used. We first used different V S values as engineering bedrock to derive a set of analytical site periods, and tested the uncertainty because of the bedrock V S selection on the GMPE variability. The results show that adding information about the stiff-soil or soft-rock layer beneath the surface soft-soil layers would significantly improve site effect prediction accuracy. An engineering bedrock with V S equal to about 800 m/s is recommended. We then tested the uncertainty of site period because of the choice between the analytical one and the empirical one on the GMPE variability. The empirical site period is better than the analytical site period at spectral periods from 0.06s to 0.4s. At spectral periods longer than 0.4s, the empirical site period produces larger variability than the analytical one using V S ≥ 800 m/s bedrock and has a better performance than that using V S < 600 m/s bedrock. The larger variability is partly contributed by the uncertainty in identifying site period value from the HVSR curve. Using the site period from the first peak of the HVSR curve generally produces a smaller variability than that from the highest peak. For sites with more than one comparable peak in the HVSR curve, the site period from the first peak is recommended. For the regions out of Japan, cautions may be paid for these recommendations because of the potential region dependence of site response. • The uncertainty of site period on variabilities of ground-motion prediction equations is presented. • The modeling effects between the site period derived from V S profiles and that estimated from HVSR curves are compared. • A V S = 800 m/s bedrock is recommended in practice if a V S profile is used for site period calculation. • The site period derived from the first peak of the HVSR curve is recommended if multiple comparable peaks are identified. [ABSTRACT FROM AUTHOR]

Most mechanical oil leaks and industrial oily wastewater are in complex and harsh environments. Hence, developing a simple and efficient method to store oil or separating oil–water contaminants has become an ongoing challenge. Hierarchically porous polyetheimide (HPPEI) is a promising competitive candidate due to the combination of functional designability, featuring multilayer pores, and the excellent properties of PEI. Herein, HPPEI (micro‐ and nano‐) is developed by fused deposition modeling (FDM) printing, which enables customizable uniform pores, and green and cost‐effective supercritical CO2 foaming method. HPPEI exhibits remarkable oil content and oil adsorption rate, attributed to the nanopores functioning as "windows." Nanopores alter the adsorption mode from the "individual adsorption" of PPEI to "interconnected adsorption," accompanied by an increased storage capacity, and enhanced the overall adsorption rate due to strong capillary effect and higher adsorption rate. HPPEI modified with hydrophobic nano fumed silica (HN─SiO2), demonstrates outstanding hydrophobicity and lipophilicity features selective oil adsorption and oil–water separation, and retains excellent hydrophobic even at high temperatures and in acidic and alkaline environments. This material is expected to provide a strategy for energy conservation: selective oil adsorption from oily wastewater in harsh environments and then the oily material is utilized for lubrication areas, avoiding material waste. [ABSTRACT FROM AUTHOR]

In order to determine metal ions in aqueous solution, a millisecond pulsed solution cathode glow discharge (SCGD) source coupled with a portable spectrometer was developed for atomic emission spectrometry (AES). The millisecond pulsed SCGD source was operated with two high-voltage DC power supplies and a high-voltage pulse switch, specifically boosting the analyte excitation and sustain the glow discharge. The method to excite the plasma discharge contrasts with traditional approaches that employ a single power source. The influence of operating parameters, including pulsed voltage, pulsed frequency, duty ratio, and sample flow rate, were optimized to construct a system having good stability and improved excitation of metal ions. The optimum detection limits for Na, K, Li, Mg, Ag, Cs, Rb, and Sr were 0.17, 0.32, 0.38, 0.50, 2.65, 1.30, 0.22, and 74.02 µg·L−1, respectively. Furthermore, mountain spring, Yangtze River, and reservoir water were spiked with Ag, Rb, and Cs; the recoveries ranged from 105% to 106%, 106% to 107%, and 107% to 108% indicating that the developed system has favorable analytical performance. [ABSTRACT FROM AUTHOR]

Summary: In this work, soy protein isolates (SPIs) were subjected to microparticulation, turning soy protein ingredients into microparticles with improved thermal stability which could be used in high‐protein foods. The pH is a critical determinant in microparticulation. Our work is mainly to investigate the effect of pH on the formation and properties of protein microparticles. To clarify the effects of pH conditions on the properties of the resulting particles, microparticulation was performed at different pH conditions (7.0, 6.0 and 5.0). Aggregation behaviours described by the parameters calculated from the protein dispersion viscosity combined with the observation of the morphology change were used to analyse the particle formation process. For the microparticles prepared at pH 5.0, soy proteins were more inclined to aggregate into clusters on a micro‐scale which had a flexible conformation. After spray drying, This powder could be easily dispersed in water, creating a dispersion with a protein concentration of 10 wt%. At this concentration, the thermal gelation capacity of the proteins was observed to decrease. Conversely, the tendency of protein aggregation was largely restricted when soy protein microparticulation was carried out at pH 7.0. As these soy protein particles in nano‐scale were dispersed in water, a decrease rather than an increase was recorded in the viscosity of this dispersion after it was heated, suggesting that these particles had improved thermal stability. This work has demonstrated that implementing appropriate pH conditions during microparticulation can prepare soy protein particles with different sizes and rheological properties, which might meet the demands of various food processing. [ABSTRACT FROM AUTHOR]

A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N 2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives. • A new phosphorus-free flame retardant was synthesized under solvent-free conditions. • The preparation process was simple, cost-effective and environmentally friendly. • Cotton fabric achieved the LOI of 28.3 % and passed vertical combustion test. • The hydrophobicity of the flame-retardant cotton fabric was also enhanced. [ABSTRACT FROM AUTHOR]

Starch granule oleogels were prepared and their rheological properties were precisely tuned using the capillary bridging phenomenon. The addition of a small amount of water to an oily suspension of starch granules can lead to starch granule bridging and network formation, transitioning it from a fluid-like to a gel-like state. Small-granule starches with high specific surface area and interfacial area exhibited a greater number of liquid bridges and stronger starch granules interactions, making them more prone to forming structurally stable oleogel systems. By increasing the content of water and starch granule, the starch oleogels exhibited three distinct structural states: pendular state (water ≤ 3.28 %, starch ≤ 17.85 %), pendular bridging network (water: 4.92 %, starch: 24.59 %), and capillary aggregates (water ≥ 6.56 %, starch > 24.59 %). Furthermore, the influence of starch granule surface lipids on the lubrication performance of the oleogel system was investigated. Surface roughness increased after extraction of surface lipids, and the friction coefficient also showed a significant increase. Overall, capillary suspension system can potentially be used to design novel fat food products, and our findings have established the correlation between starch granule surface properties and sensory perception in food, providing valuable insights for adjusting the oral processing characteristics of food. [Display omitted] [ABSTRACT FROM AUTHOR]

3D printing has extremely high requirements for the design of food matrices with suitable rheological properties. Starch exhibits considerable potential as a material for 3D printing. However, there is limited research available on the direct fabrication of oleogels using starch granules as building blocks. In this study, we developed a simple approach to fabricate plant-based oleogels as edible 3D printable materials by exploiting capillary forces between starch granules. When a small amount of water (less than 5 wt%) was added to starch granules dispersed in an oil phase, a pendular bridging network was formed between the starch granules. The rheological properties of the starch-oil suspension were significantly changed, transitioning it from a fluid-like to a gel-like state. The rheological properties of the oleogel could be altered by varying the starch granule volume fraction, the amount of water added, the structure of starch granules, and the oil-water interfacial tension. Confocal laser microscopy imaging demonstrated that starch granule oleogels exhibit three distinct structural states: pendular state, pendular bridge network, and capillary aggregation. Furthermore, the presence of water was identified as a liquid bridge between starch granules. Additionally, starch granule oleogels exhibited excellent thermal stability and freeze-thaw stability. Overall, this approach enhances the feasibility of preparing starch oleogels and provides valuable insights for the personalized 3D printing of oleogels. [Display omitted] • Starch granule based oleogels were successfully prepared through capillary attraction. • Untreated native starch granules were firstly used in the preparation of oleogels. • The oleogel network was formed by granules connected through meniscus bridges. • Modulating rheological properties of the oleogel via added water or starch content. [ABSTRACT FROM AUTHOR]

The reduction of sodium intake without affecting saltiness perception is still a huge challenge. The acid method (pH 2.0, 85 °C, 90min) and subcritical water treatment (SW, pH 6.3–2.0, 120 °C, 30min) were used to prepare saltiness-enhanced polysaccharides from soy hull. Structural and physicochemical properties of soy hull polysaccharides (SHP) and their relationship to the salivary diffusion and mucosal retention of Na+ were analyzed. Compared to acid-extracted SHP (ASHP), SW-extracted SHP (SW6.3, SW5.0, and SW4.0) exhibited a higher saltiness-enhanced effect, accompanied by an accelerated diffusion of Na+ in the saliva and enhanced adhesive retention of Na+ on the porcine tongue. These phenomena may be attributed to different fractions extracted by two methods. ASHP mainly consists of pectic polysaccharides with a higher galacturonic acid content, while RG-I enriched pectic and hemicellulosic polysaccharides were speculated for SW6.3, SW5.0 and SW4.0, which exhibited highly branched conformation with higher M w and lower charge. The SHP-induced disruption of the salivary mucin network probably accelerates the Na+ permeation and the adhesion of Na+ on the porcine tongue. SW3.0 and SW2.0 showed lower apparent viscosity and M w due to excessive degradation of the backbone and side chain, weakening the diffusion and adhesion of Na+, and salt taste. These results would be useful to reveal the regulatory mechanism of polysaccharides on saltiness perception, which provided a technology to prepare a saltiness-enhanced ingredient from a by-product of soybean processing for low-sodium foods. [Display omitted] • The salivary penetration and mucosal retention of Na + strongly affect salty taste. • The saltiness-enhanced effect of SW-extracted SHP was higher than that of ASHP. • SW-extracted SHP exhibit higher salivary penetration and retention of Na+. • SW extracted high-branched RG-I enriched SHP with higher M w and lower charge. [ABSTRACT FROM AUTHOR]

Seed-type hemp fiber is hard to spinning and weaving because of its high lignin and hemicellulose content. In this work, the impurities in seed-type hemp fiber were removed by alkali degumming method, ammonium oxalate-complex enzyme method, ethylenediamainetetraacetic acid disodium -complex enzyme method, ammonium oxalate-complex enzyme-chemical method and ethylenediamainetetraacetic acid disodium -complex enzyme-chemical method, and the results were compared. The fibers were characterized by scanning electron microscopy (SEM) and fourier-transform infrared spectroscopy (FTIR). The fiber after impurity removal is prepared into pulp, and the structure of pulp was characterized by fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The hemp pulp was dissolved into ZnCl 2 aqueous solution at a specific temperature to prepare a spinning solution and spun to produce antimicrobial seed-type hemp regenerated cellulose fibers by using a self-made spinning machine. The surface morphology, strength, moisture regain, and antibacterial properties were evaluated, the regenerated fibers had a superior performance. • A functional regenerated cellulose fibers had been prepared from seed-type hemp fibers which are difficult to spin. • The seed-type hemp fiber degumming treatment was improved by using a biological enzyme & chemical composite technology. • ZnCl 2 solution was used to dissolve seed-type hemp fiber and wet spin with environmentally friendly consumption. [ABSTRACT FROM AUTHOR]