Publications by authors named "Wuyong Chen"

In leather manufacturing, microwave usually has the ability to strengthen the combination between collagen and chemicals and make the corresponding procedures faster and more effective. Although some studies clarified that tanning under microwave resulted in leather with better thermal stability, the process and leather properties of the pelt chrome tanning had not been elaborated in detail. Thus, in this study, pickled goat pelt was tanned for 5 h as a penetration procedure and then basified for another 5 h as a fixation procedure under microwave heating (MW) and water bath heating (WB); then, the changes in the pH of the chromium complexes as well as the leather chrome content were measured; finally, thermal behaviors and collagen structure of leather tanned under different methods were measured.

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To meet the extremely strict requirements of tannery wastewater, scientists need to urgently devise novel methods for controlling the quality of tannery wastewater. With these methods, it would be easier to promote sustainable development in the tannery industry. In this article, we summarize the following aspects of tannery wastewater: (i) the sources and characteristics of tannery wastewater, (ii) the main treatment methods (primary, secondary, and tertiary treatments), and (iii) resource utilization status of wastewater.

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The aim of this study was to design an algorithm to quantify the plantar force transference of children from ages 2-6. In total, 319 healthy children without abnormal gait patterns, foot deformities or injuries, able to walk independently, and with normal BMIs were recruited, and their plantar force distributions were measured. Their plantar areas were divided into ten parts: the hallux, toes #2-5, the first to fifth metatarsal heads (1st-5th MTH), the mid-foot (MF), medial heel (MH) and lateral heel (LH), in which a relative force-time integral (FTIrel) (%) was calculated.

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The aim of this study was first to quantify intra-limb coordination and then to explore the gender differences of 180 healthy children aged 3-6. The children's joint Euler angles and angular velocities were measured and were used to calculate the phase angle (PA) and continuous relative phase (CRP). Firstly, a portrait of the mean and standard deviation (SD) of PA and CRP was applied to quantify coordination in the knees and ankles; then five key events in walking were selected and their inter-age differences were assessed by One-way ANOVA.

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This study aimed at quantitatively evaluating the effectiveness of sheepskin mattress (SSM) in pressure relieving, and then variables of peak pressure (mmHg) (PP), average pressure (AP) and contact area (cm(2)) (CA) at the total, back, sacrum and heel regions of 18 students supinely lying in a control mattress (CM), standard hospital mattress (SHM), SHM+SSM, SSM+CM and AM+CM were measured and contrasted. Paired-T test with a significant level of .05 shows that: the intervention of SSM significantly increased the total CA of SHM by 395.

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Background: There is medium correlation between the current anthropometric method and the radiography in the angle of hallux valgus (AoH) measurement, so this study aimed at designing a reliable and more accurate approach to measure the AoH (AoH).

Materials And Methods: Fifteen age, body weight, and height matched male students were included and those with foot disorders, deformities, or injuries were excluded from the study. The dorsal protrusions of the first metatarsal and the hallux were marked by palpating from three experienced observers; then their barefoot model in standing was collected by a three dimensional laser scanning system.

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Influence of microwave-assisted extraction (MAE) to the characterization and corresponding antioxidant activity of polysaccharides from Auricularia auricula (AAP) was determined. According to gas chromatography-mass spectrometry, high performance size exclusion chromatography, Fourier transform infrared spectroscopy, partial acid hydrolysis, periodic acid oxidation, Smith degradation, methylation analysis and atomic force microscopy, AAP was a heteropolysaccharide (composed of glucose, galactose, mannose, arabinose and rhamnose at the molar ratio of 37.53:1:4.

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Bacillus cereus was used to remove chromium (Cr(VI)) from medium containing tannery wastewater under different conditions. The maximum rate of Cr(VI) removal was attained at a temperature of 37 °C, pH of 7.0-9.

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In this study, the original causes for hexavalent chromium presence in the leather were first evaluated by ageing of chromium(III) solutions and chrome tanned hide powder (50 degrees C, UV lightening at 340 nm, 0-36 h). The results showed that the trivalent chromium at instable coordination state was easy to convert into hexavalent chromium in high pH environment, and the probability of the oxidation increased in this order: multi-coordinate chromium, mono-coordinate chromium, and free chromium. For this reason, the process for stabilizing chromium in the leather was designed with the specific material, which was mostly consisted of the reducers and the chelating agents.

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Article Synopsis
  • Enzymatic unhairing is a clean technology in the leather industry, but enzyme diffusion through skins is slow.
  • Ultrasound can accelerate this diffusion, and in this study, a frequency of 20kHz was found to enhance the efficiency of enzymatic unhairing without affecting enzyme activity or the leather's physical properties.
  • Amylase, which interacts with proteoglycans, can work effectively with ultrasound to improve unhairing capacity, making it a safe option for use alongside protease in environmentally-friendly leather processing.
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