Long-term development of compressive strength and elastic modulus of concrete

Yang, Shuzhen,Liu, Baodong,Yang, Mingzhe,Li, Yuzhong Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.2

Compressive strength and elastic modulus of concrete are constantly changing with age. In order to determine long-term development of compressive strength and elastic modulus of concrete, an investigation of C30 concrete cured in air conditions was carried out. Changes of compressive strength and elastic modulus up to 975 days were given. The results indicated that compressive strength and elastic modulus of concrete rapidly increased with age during the initial 150 days and then increased slowly. The gain in elastic modulus was slower than that of compressive strength. Then relationships of time-compressive strength, time-elastic modulus and compressive strength-elastic modulus were proposed by regression analysis and compared with other investigations. The trends of time-compressive strength and time-elastic modulus with age agreed best with ACI 209R-92. Finally, factors contributed to long-term development of compressive strength and elastic modulus of concrete were proposed and briefly analyzed.

Effects of environmental temperature and age on the elastic modulus of concrete

Shuzhen Yang,Baodong Liu,Yuzhong Li,Minqiang Zhang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.72 No.6

Concrete mechanical properties change constantly with age, temperature, humidity and the other environmental factors. This research studies the effects of temperature and age on the development of concrete elastic modulus by a series of prism specimens. Elastic modulus test was conducted at various temperatures and ages in the laboratory to examine the effects of temperature and age on it. The experimental results reveal that the concrete elastic modulus decreases with the rise of temperature but increases with age. Then, a temperature coefficient K is proposed to describe the effects of temperature and validated by existing studies. Finally, on the basis of K, analytical models are proposed to determine the elastic modulus of concrete at a given temperature and age. The proposed models can offer designers an approach to obtain more accurate properties of concrete structures through the elastic modulus modification based on actual age and temperature, rather than using a value merely based on laboratory testing.

Long-term development of compressive strength and elastic modulus of concrete

Shuzhen Yang,Baodong Liu,Mingzhe Yang,Yuzhong Li 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.2

Compressive strength and elastic modulus of concrete are constantly changing with age. In order to determine long-term development of compressive strength and elastic modulus of concrete, an investigation of C30 concrete cured in air conditions was carried out. Changes of compressive strength and elastic modulus up to 975 days were given. The results indicated that compressive strength and elastic modulus of concrete rapidly increased with age during the initial 150 days and then increased slowly. The gain in elastic modulus was slower than that of compressive strength. Then relationships of time-compressive strength, time-elastic modulus and compressive strength-elastic modulus were proposed by regression analysis and compared with other investigations. The trends of time-compressive strength and time-elastic modulus with age agreed best with ACI 209R-92. Finally, factors contributed to long-term development of compressive strength and elastic modulus of concrete were proposed and briefly analyzed.

Control of Citrus Green and Blue Molds by Chinese Propolis

Shuzhen Yang,Litao Peng,Yunjiang Cheng,Siyi Pan,Feng Chen 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.5

Green and blue molds, caused by Penicillium digitatum and Penicillium italicum, respectively, are economically important postharvest diseases of citrus fruits. In this study, Chinese propolis ethyl acetate extract (PEAE) was evaluated to control P. digitatum and P. italicum on postharvest citrus fruits. The results indicated PEAE strongly inhibited mycelia growth and induced hyphae prominent abnormal morphological alterations. Also, PEAE had strong detrimental effect on spore germination of the tested pathogens in a concentrationdependent manner. For in vivo tests, PEAE could both reduce decay caused by P. digitatum and P. italicum respectively in wound-inoculated fruit and naturally infected fruit; meanwhile, no negative influences on the overall quality of the citrus fruits were observed with PEAE treatment. Therefore, PEAE could be used as a natural antifungal agent to control citrus blue and green mold.

Antifungal Activity and Action Mode of Pinocembrin from Propolis against Penicillium italicum

Litao Peng,Shuzhen Yang,Yunjiang Cheng,Feng Chen,Siyi Pan,Gang Fan 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.6

The antifungal activity and possible mode of action of pinocembrin isolated from propolis against Penicillium italicum were investigated. Pinocembrin exhibited strong antifungal activity against P. italicum in a dosedependent manner. Respiration rates of P. italicum during spore germination and mycelial growth were significantly inhibited when exposure to pinocembrin. The respirations of mitochondria in state 2 and state 3 from mycelia were significantly inhibited in the presence of this compound. The phosphorylated adenosine nucleotides levels in hyphae of P. italicum treated with pinocembrin were significantly low and energy charge value became unstable. Unltrastructure of hyphae was seriously damaged with pinocembrin incubation for 24 h, which was further confirmed by the increase of relative ionic leakage and soluble protein loss of P. italicum mycelia treated with pinocembrin. It was concluded that pinocembrin inhibited the mycelial growth of P. italicum by interfering energy homeostasis and cell membrane damage of the pathogen. Pinocembrin would be a promising bioactive compound for treatment of P. italicum infections on postharvest citrus fruit.

Zearalenone exposure affects the Wnt/β-catenin signaling pathway and related genes of porcine endometrial epithelial cells in vitro

Song Tingting,Yang Weiren,Huang Libo,Yang Zaibin,Jiang Shuzhen 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.6

Objective: Zearalenone (ZEA) has estrogen-like effects. Our previous study has shown that ZEA (0.5 to 1.5 mg/kg) could induce abnormal uterine proliferation through transforming growth factor signaling pathway. To further study the other regulatory networks of uterine hypertrophy caused by ZEA, the potential mechanism of ZEA on porcine endometrial epithelial cells (PECs) was explored by the Illumina Hiseq 2000 sequencing system. Methods: The PECs were treated with ZEA at 0 (ZEA0), 5 (ZEA5), 20 (ZEA20), and 80 (ZEA80) μmol/L for 24 h. The collected cells were subjected to cell cycle, RNA-seq, real-time quantitative polymerase chain reaction, immunofluorescence, and western blot analysis. Results: The proportion of cells in the S and G2 phases decreased (p<0.05), but the proportion of cells in the G1 phase increased (p<0.05) in the ZEA80 treatment. Data analysis revealed that the expression of Wnt pathway-related genes, estrogen-related genes, and mitogen-activated protein kinase pathway-related genes increased (p<0.05), but the expression of genetic stability genes decreased (p<0.05) with increasing ZEA concentrations. The relative mRNA and protein expression of WNT1, β-catenin, glycogen synthase kinase 3β (GSK-3β) were increased (p<0.05) with ZEA increasing, while the relative mRNA and protein expression of cyclin D1 (CCND1) was decreased (p<0.05). Moreover, our immunofluorescence results indicate that β-catenin accumulated around the nucleus from the cell membrane and cytoplasm with increasing ZEA concentrations. Conclusion: In summary, ZEA can activate the Wnt/β-catenin signaling pathway by upregulating WNT1 and β-catenin expression, to promote the proliferation and development of PECs. At the same time, the up-regulation of GSK-3β and down-regulation of CCND1, as well as the mRNA expression of other pathway related genes indicated that other potential effects of ZEA on the uterine development need further study. Objective: Zearalenone (ZEA) has estrogen-like effects. Our previous study has shown that ZEA (0.5 to 1.5 mg/kg) could induce abnormal uterine proliferation through transforming growth factor signaling pathway. To further study the other regulatory networks of uterine hypertrophy caused by ZEA, the potential mechanism of ZEA on porcine endometrial epithelial cells (PECs) was explored by the Illumina Hiseq 2000 sequencing system.Methods: The PECs were treated with ZEA at 0 (ZEA0), 5 (ZEA5), 20 (ZEA20), and 80 (ZEA80) μmol/L for 24 h. The collected cells were subjected to cell cycle, RNA-seq, real-time quantitative polymerase chain reaction, immunofluorescence, and western blot analysis.Results: The proportion of cells in the S and G2 phases decreased (p<0.05), but the proportion of cells in the G1 phase increased (p<0.05) in the ZEA80 treatment. Data analysis revealed that the expression of Wnt pathway-related genes, estrogen-related genes, and mitogen-activated protein kinase pathway-related genes increased (p<0.05), but the expression of genetic stability genes decreased (p<0.05) with increasing ZEA concentrations. The relative mRNA and protein expression of WNT1, β-catenin, glycogen synthase kinase 3β (GSK-3β) were increased (p<0.05) with ZEA increasing, while the relative mRNA and protein expression of cyclin D1 (CCND1) was decreased (p<0.05). Moreover, our immunofluorescence results indicate that β-catenin accumulated around the nucleus from the cell membrane and cytoplasm with increasing ZEA concentrations.Conclusion: In summary, ZEA can activate the Wnt/β-catenin signaling pathway by up-regulating WNT1 and β-catenin expression, to promote the proliferation and development of PECs. At the same time, the up-regulation of GSK-3β and down-regulation of CCND1, as well as the mRNA expression of other pathway related genes indicated that other potential effects of ZEA on the uterine development need further study.

Selection and Validation of Reference Genes for Quantitative Real-Time PCR in Artemisia sphaerocephala Based on Transcriptome Sequence Data

Xiaowei Hu,Shuzhen Nan,Xiumei Miao,Yuanyuan Zhao,Guoqin Duan,Pengfang Yang,Xiaolong Chen,Lijing zhang,Hua Fu 한국초지조사료학회 2016 한국초지조사료학회 학술대회논문집 Vol.2016 No.08

Seismic Performance Analysis of Buckling-Restrained Braced Steel Frames with Ductile Castings

Zhanzhong Yin,Bo Yang,Shuzhen An 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.10

Buckling-restrained brace (BRB) steel frames with ductile castings are proposed to solve the fracture failure of welded joints between buckling-restrained braces and frames after rare earthquakes. In this paper, quasi-static tests are conducted on two one-story, one-bay steel frames to study their mechanical behaviors, including stress distribution, failure mode, energy dissipation, and skeleton curve, and finite element models are established for verification. Subsequently, 22 models with different parameters of the BRB steel frames with ductile castings are analyzed using ABAQUS. Results indicate that the new frame system has good energy dissipation; it can confine the inelastic deformation of the structure to the ductile castings and BRB. It also satisfies the 1/50 maximum elastic-plastic drift angle set by the Code for Seismic Design of Buildings. The BRB with ductile castings connected to the frames by bolts can relieve the stress distribution in the beam–column region, which can be assembled and replaced after the earthquake.

Zearalenone Altered the Serum Hormones, Morphologic and Apoptotic Measurements of Genital Organs in Post-weaning Gilts

Chen, X.X.,Yang, C.W.,Huang, L.B.,Niu, Q.S.,Jiang, Shuzhen,Chi, F. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.2

The present study was aimed at investigating the adverse effects of dietary zearalenone (ZEA) (1.1 to 3.2 mg/kg diet) on serum hormones, morphologic and apoptotic measurements of genital organs in post-weaning gilts. A total of twenty gilts ($Landrace{\times}Yorkshire{\times}Duroc$) weaned at 21 d with an average body weight of $10.36{\pm}1.21kg$ were used in the study. Gilts were fed a basal diet with an addition of 0, 1.1, 2.0, or 3.2 mg/kg purified ZEA for 18 d ad libitum. Results showed that 3.2 mg/kg ZEA challenged gilts decreased (p<0.05) the serum levels of luteinizing hormone, however, serum levels of prolactin in gilts fed the diet containing 2.0 mg/kg ZEA or more were increased (p<0.05) compared to those in the control. Linear effects on all tested serum hormones except progesterone were observed as dietary ZEA levels increased (p<0.05). Gilts fed ZEA-contaminated diet showed increase (p<0.05) in genital organs size, hyperplasia of submucosal smooth muscles in the corpus uteri in a dose-dependent manner. However, the decreased numbers of follicles in the cortex and apoptotic cells in the ovarian were observed in gilts treated with ZEA in a dose-dependent manner. Degeneration and structural abnormalities of genital organs tissues were also observed in the gilts fed diet containing 1.1 mg/kg ZEA or more. Results suggested that dietary ZEA at 1.1 to 3.2 mg/kg can induce endocrine disturbance and damage genital organs in post-weaning gilts.

Investment and Risk Control of China's Mining Enterprises

Yunzhong Liu,Li Gao,Shuzhen Yao,Lin Yang 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

Mining investment environment influences mining business risk factors. How enterprises face changing environment and implement successful risk management is the central task for mining enterprise management and development. This paper begins with the analysis of Chinn"s mining invesment environment, identifiesrisk factors of S Mining Limited Company, explores its risk control countermeasures, and propose resolutions of risk management for mining enterprises.