Polyethylene Terephthalate/Carbon Fabric/Polyurethane Foam Sandwich Composites: Flame Retardance and Mechanical Properties

Liwei Wu,Jingyan Ban,Qian Jiang,Ting-Ting Li,Bing-Chiuan Shiu,Shih-Yu Huang,Ching-Wen Lou,Jia-Horng Lin 한국섬유공학회 2019 Fibers and polymers Vol.20 No.6

Polyethylene terephthalate (PET) nonwoven fabrics, carbon fabrics (CF), and flexible polyurethane (PU) foamsare made into novel sandwich composites using one-step molding. The flame retradance and mechanical properties of thesandwich composites are evaluated, examining the influences of the content of flame retardant agent (20, 30, 40, and 50 wt%)and areal density of PET panels (200, 300, and 400 g/m2). The test results show that the PET/CF/PU sandwich composites arerated flame retardant as V0 and do not generate melts. The failure mode of PET/CF/PU sandwich composites converts fromoverall fracture to layered fracture as a result of increasing the flame retardant agent. The tensile strength at break of PET/CF/PU sandwich composites with corresponding PET panels is 650 N for 200 g/m2, 928 N for 300 g/m2, and 1744 N for 400 g/m2,which are 42.63 %, 60.48 %, and 77.85 % greater than those of the PET/PU sandwich composites. Moreover, the burstingstrength of PET/CF/PU sandwich composites with corresponding PET panels is 3322 N for 200 g/m2, 3869 N for 300 g/m2,and 4978 N for 400 g/m2, which are 195 %, 180 %, and 143 % greater than those of the PET/PU sandwich composites.

Reliability analysis of degradation with a new independent increment process

Qiong Wu,Jianzhong Yang,Jingyan Wang,Li Xue 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.10

Degradation test is an important method to assess the reliability of complex systems and highly reliable products. The effectiveness ofa degradation model depends strongly on the suitability of the model to describe the process. This paper proposes a new degradationmodel in which the characteristics of the widely used stochastic process and degradation path models are considered simultaneously. According to the proposed model, closed-form expressions of the performance distribution, failure time distribution and their percentiles,as well as reliability, can be obtained easily. A one-stage procedure is then developed to estimate the model parameters, based on which,estimations of the performance distribution, failure time distribution, and reliability are also presented in the paper. Finally, simulationstudies are conducted to validate the proposed method. Results suggest that the method provides precise estimates even for zero-failurecases or an extremely small sample size of approximately five.

Which Factors Help Visitors Convert Their Short-Term Pro-Environmental Intentions to Long-Term Behaviors?

Jialin Wu,Danyu Huang,Jingyan Liu,Rob Law 한국관광학회 2013 International Journal of Tourism Sciences Vol.13 No.2

The theoretical perspective of this study is to integrate Visitor Environmental Learning (VEL) into the Theory of Planed Behavior (TPB). The Xiangjiang Safari Park, which is one of the largest theme parks in Asia,was selected to test the conceptual model to examine whether Post-Visit Action Resources (PVAR), Ease of Behavior (EB), and Sunk Cost (SC) have the mediate/moderate effect on the relationship between short-term pro-environment intentions and long-term behaviors. The sample consisted of 269 tourists who have travel experience with the Xiangjiang Safari Park. Findings from a Structural Equation Model analysis show that post-visit action resources partially mediate the relationship between tourists’ short-term pro-environmental intentions and behaviors, and that ease of behavior and sunk cost both have moderating effects on this relationship. These findings indicate that a high level of post-visit action resources, ease of behavior and sunk cost are instrumental in encouraging visitors’ pro-environmental intentions to turn into behaviors.

Responses of Antioxidant Enzyme Activity to Different Fertilizer and Soil Moisture Conditions in Relation to Cold Resistance in Zanthoxylum armatum

Jiangtao Fan,Jingyan Wang,Xianzhi Liu,Changping Zhao,Chaobing Zhou,Tasheen Saba,Jiaojiao Wu,Wenkai Hui,Wei Gong 한국원예학회 2022 원예과학기술지 Vol.40 No.3

Zanthoxylum armatum, known as green prickly ash, is a major condiment species planted on a large scale in southwest China. However, its limited cold tolerance has been a significant disadvantage for its cultivation in low-temperature regions. To better understand the antioxidant enzyme activities related to cold resistance, superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities as well as malondialdehyde (MDA) content were investigated under 16 fertilizer and soil moisture treatments to explore the cold resistance response mechanism in Z. armatum. The results showed that low temperatures could significantly affect antioxidant enzyme activities in the leaves of Z. armatum seedlings. The antioxidant enzyme activities of seedlings treated with soil moisture and fertilizer treatments were significantly higher than those without fertilizer. Furthermore, the comprehensive evaluation index (CEI) was positively correlated with SOD, POD, and CAT activities but negatively correlated with MDA content. Meanwhile, the treatment T12 (60% field water capacity + 300 kg·ha-1 nitrogen + 30 kg·ha-1 phosphoric anhydride) had the highest CEI value, whereas T1 (20% water capacity) had the lowest. Based on the regression equation for CEI improvement, the predicted optimal levels for field water capacity (FWC), nitrogen, phosphorus, and potassium were 59.6%–63.4% FWC (average 61.5%), 114.2–248.8 kg N/ha (average 181.5 kg N/ha), 40.1–108.5 kg P2O5/ha (average 74.3 kg P2O5/ha), and 200.2–254.4 kg K2O/ha (average 227.3 kg K2O/ha), respectively. The present study provides the optimal soil moisture and fertilizer concentration required to enhance protective enzyme activity and low-temperature tolerance, which is crucial for improving cold resistance in Z. armatum.

Response of Photosynthetic Characteristics to Different Salicylic Acid Concentrations in Relation to Waterlogging Resistance in Zanthoxylum armatum

Peiyun Wang,Chengyi Su,Jiaojiao Wu,Yuxin Xie,Jiangtao Fan,Jingyan Wang,Wenkai Hui,Hua Yang,Wei Gong 한국원예학회 2023 원예과학기술지 Vol.41 No.4

Zanthoxylum armatum (Rutaceae) is an important spice and a traditional medicinal plant in southwest China. Owing to its shallow root system, it is highly susceptible to waterlogging stress. To evaluate how an exogenous salicylic acid (SA) application reduces photosynthetic damage in Z. armatum under waterlogging stress conditions, the content of photosynthetic pigments and gas exchange and chlorophyll fluorescence parameters were studied under different SA concentrations (0, 1 and 2 mM) and different numbers of waterlogging days (1, 2 and 3 d) to identify the mechanisms underlying the seedlings’ waterlogging response. The results showed that waterlogging significantly affects the photosynthetic characteristics in leaves. An exogenous SA application increased the contents of photosynthetic pigments as well as the transpiration rate (Tr), net leaf photosynthetic rate (Pn), stomatal conductance (Gs), water use efficiency (WUE), actual quantum efficiency (ΦPSII), photosystem II (PSII) maximum quantum efficiency (Fv/Fm), PSII photochemical efficiency in light (Fv'/Fm'), and electron transport rate (ETR), whereas the treatment decreased the intercellular carbon dioxide concentration (Ci), non-photochemical quenching coefficient (NPQ) and minimum fluorescence (Fo). Therefore, the SA application helps improve the photosynthetic efficiency and reduce photodamage to Z. armatum in the event of waterlogging stress.

The miR-145-5p/CD36 pathway mediates PCB2-induced apoptosis in MCF-7 cells

Yuan Yuan,Caihua Xue,Qiang Wu,Mengjie Wang,Jiahua Liu,Longfei Zhang,Qianwen Xing,Jingyan Liang,Hua Wu,Zhi Chen 한국유전학회 2021 Genes & Genomics Vol.43 No.2

Background Procyanidin B2 (PCB2) can increase the levels of anti-infammatory and immune mediators. Objectives However, its molecular mechanism in human breast cancer remains unclear. This study aimed to investigate the antitumor efect of PCB2 on MCF-7 cells and to examine the underlying mechanism. Methods The fow cytometry and EdU incorporation assays were measured the PCB2-induced BMECs. The expression levels of infammatory factors and immune response genes were upregulated in MCF-7 cells, high-throughput sequencing was used to detect diferentially expressed genes in blank and PCB2-treated MCF-7 cells. Results The results showed that PCB2 induced the apoptosis of MCF-7 cells. CD36 profles were afected in MCF-7 cells. Additionally, prediction software identifed a miR-145-5p binding site in the CD36 sequence. Luciferase reporter assays and Western blot analysis were used to verify the regulatory relationships between the diferentially expressed miRNA miR145-5p and CD36. MiR-145-5p and its key target (CD36) constitute a potential miRNA-mRNA regulatory pair. Functional studies in MCF-7 cells revealed that CD36 promotes but miR-145-5p inhibits apoptosis. Conclusion Overall, these data suggest that miR-145-5p inhibits the enhancing efect of PCB2 on CD36 expression by binding CD36 and subsequently regulating apoptosis, the immune response and anti-infammatory pathways. These results provide theoretical and experimental support for the treatment of breast cancer.

Effects of pigment and citrinin biosynthesis on the metabolism and morphology of Monascus purpureus in submerged fermentation

Xueying Chai,Zhilu Ai,Jun Liu,Ting Guo,Jingyan Wu,Jie Bai,Qinlu Lin 한국식품과학회 2020 Food Science and Biotechnology Vol.29 No.7

The effects of the secondary metabolite biosynthesison the metabolism and morphology of the Monascuspurpureus were investigated in this study. Hypha andseptum length became longer after deletion of genes pigRand pksCT in M. purpureus LQ-6 by Agrobacteriumtumefaciens-mediated transformation technology, highlybranched hyphae, much smaller and freely dispersedmycelial pellets were observed in M. purpureus. Comparedwith that in the wild-type, the level of intracellular NADHand NADPH was almost constant in M. purpureus DpigRat 4 days, but the NADH and NADPH levels decreased by1.58-fold and 3.71-fold in M. purpureus DpksCT. Thepresent study can not only provide a kind of strategy toimprove the Monascus pigments production, but also providetheoretical support for the further study of relationshipbetween the secondary metabolites, metabolism and morphologicalchange.