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The effect of multi-frequency pulsed ultrasound (20 kHz, 20 + 28 kHz, and 20 + 28 + 40 kHz) on characteristics of a peach pulp-κ-carrageenan blend gel system containing erythritol as a cosolute was systematically studied. Rheological analysis showed that the blend gel system was a pseudoplastic fluid. With the increase in pulsed ultrasound frequency, the consistency coefficient increased and the flow index decreased. Dynamic rheological analysis showed that single-frequency and dual-frequency pulsed ultrasound could significantly enhance the elastic modulus (G’) and viscosity modulus (G”), while triple-frequency pulsed ultrasound had the opposite effect. The particle size was significantly reduced by the cavitation effect produced by multi-frequency pulsed ultrasound, the effect being most pronounced with triple-frequency pulsed ultrasound. Compared with the control group, D50, D[4,3], and D[3,2] of the samples treated by triple-frequency pulsed ultrasound were decreased by 12.32%, 9.80% and 7.57%, respectively. Additionally, multi-frequency pulsed ultrasound could increase the absolute value of the phase angle and conductivity, and reduce the impedance value. Compared with the control group, the absolute value of the phase angle and the conductivity were increased by 35.82% and 10.15% in the triple-frequency pulsed ultrasound group, respectively; and the impedance value was reduced by 38.52%. As the pulsed ultrasound frequency increased, the association between the blend system and water was enhanced, so that a bound water signal appeared. No new absorption peaks were found in the Fourier transform infrared spectra of ultrasound-treated samples, indicating that ultrasound treatment did not destroy the functional groups, but instead only strengthened hydrogen bonding. The micropores of the blend gel system were enlarged by both single-frequency and dual-frequency pulsed ultrasound treatments, while triple-frequency pulsed ultrasound treatment resulted in denser and more uniform pores. This study can provide a reference for improving the quality of blend gels of κ-carrageenan and developing gel-like peach pulp products.

When the surface strain field of concrete structure is measured by digital image correlation(DIC)technology under complex light conditions, the decorrelation effect of the pattern will be caused by the variation in light intensity. For this problem, the optimal light intensity suitable for DIC calculating and analyzing is studied, and the influence of light intensity variation on the measurement accuracy and calculation efficiency of DIC is explored by the traditional 2D-DIC measurement system. The experimental result shows that the average gray level of 190 is the optimal light intensity. The picture is used as the reference image at the optimal light intensity. The strain error increases exponentially when the light intensity increases, and the strain error increases linearly when the light intensity decreases. The computation time and the matching rate of calculation points are insensitive to the slight range fluctuation of light intensity, while the computation time of DIC will increase 1 to 3 times, and about 25 % of calculation points will match failed because of the extreme variation of light intensity. The accuracy of experimental results is verified by Combining them with the image quality assessment index. In order to get high-quality images, the green band-pass filter imaging system is established in this paper. It can stabilize the image's brightness and contrast when the external light varies seriously. The strain error and calculation efficiency are all close to the optimal light intensity when external ambient light changes seriously. Compared with the traditional 2D-DIC measurement system, The green band-pass filter imaging system can be better applied to measure in the outdoor environment.

In order to explore the differences in the aroma quality of different white-fleshed peach cultivars, an electronic nose and headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to analyze the volatile components of eight cultivars of white-fleshed peach including Baiyintao (BYT), Longmi 5 (LM5H), Xinchuanzhongdao (XCZD), Qiutong (QT), Xindajiubao (XDJB), Yihongmi (YHM), Yihongshuimi (YHSM) and Okayama (GSB). Relative odor activity value (ROAV) and variable importance in projection (VIP) were used to analyze the contribution of each volatile component to the overall aroma of white-fleshed peaches. In the electronic nose radar fingerprint, the W1W, W5S, W1S and W2W sensors showed different responses to the eight cultivars. Principal component analysis (PCA) demonstrated differences in the overall aroma of white-fleshed peach cultivars. In total, 49, 46, 46, 47, 49, 47, 47, 53 volatile compounds were identified in BYT, LM5H, XCZD, QT, XDJB, YHM, YHSM, and GSB by HS-SPME-GC-MS, respectively, the major ones being aldehydes, alcohols, lactones and esters. 2-Hexenal, hexanal, trans-2-hexenal and trans-2-hexen-1-ol, contributing to grass aroma; linalool, contributing to floral aroma; and n-hexanol, responsible for fruity aroma, were identified as key aroma compounds due to their ROAV ≥ 1 and VIP > 1. Variations in their concentrations caused differences in the key aroma of the eight white-fleshed peach cultivars.

In the last four decades, the Jiangsu province, like the rest of China, has undergone rapid economic development coupled with a rapid increase in environmental pollution. Freshwater ecosystems have been particularly affected. In Lake Tai, China's third‐largest freshwater lake by volume, water quality has been severely reduced. There is a renewed interest in establishing riparian buffer strips in China as a conservation practice for mitigating agricultural non‐point source pollution. To study the effect of riparian buffers on phosphorus attenuation, eight 50 m × 20 m plots were established between a rice farm and the shore of Lake Tai in China, with the 20 m width facing the lake shore. They were planted with hybrid poplar (Populus deltoides × euramericana), hybrid cypress (Taxodium ascendens × mucronatum), or a mixture of both at densities of 2 m × 3 m, 2 m × 5 m, or 5 m × 5 m, while one plot was left as a control. Samples collected from soil, tree leaves, and groundwater during 2014–2018 were analyzed for multiple forms of phosphorus. Results indicated that riparian buffer width and time (year) were the most significant factors of phosphorus attenuation on all plots. Tree density had a minor effect, with medium density being the most effective, and we found negligible differences among hybrid tree species on attenuating phosphorus. Farmers should use densely vegetated buffer strips at least 15 m wide to ensure a significant reduction in nutrient runoff. Species selection should be based on market value and ecological benefits. Core Ideas: Overfertilization of rice paddies is a systemic issue in China, with little incentive for farmers to change their practices.Riparian buffer strips can serve as an economically viable best management practice (BMP) for alleviating eutrophication on rice farms.A riparian buffer with a width of at least 15 m and medium tree density was found to be the most effective for attenuating phosphorus runoff. [ABSTRACT FROM AUTHOR]