Study on the Mechanical Properties and Microstructure of Geogrid Under Different Materials and Temperatures

Junli Gao,Haibing Zhang,Xuelei Xie,Yapo Zhang 한국섬유공학회 2022 Fibers and polymers Vol.23 No.6

In response to the environmental problems caused by the difficulty of direct degradation of the raw materials usedin traditional geogrids and the impact of different temperatures on the mechanical properties of geogrids in practicalengineering applications, based on 3D printing technology, polylactic acid (PLA), carbon fiber reinforced polylactic acid(PLA/CF), and thermoplastic polyurethane (TPU) geogrids were fabricated. The 3D printed geogrids and the fiberglassgeogrids used in the actual project were tested in indoor tensile tests under different temperature conditions. The mechanicalproperties of the geogrids of the four kinds of materials and six kinds of temperature were analyzed. The microstructure of thegeogrids after tensile tests was investigated based on scanning electron microscopy technology to further analyze the effectsof different materials and temperatures on the mechanical properties of the geogrids. The results showed that the tensilestrength of PLA/CF geogrids and PLA geogrids decreased with increasing temperature. The tensile strength of fiberglassgeogrids increased with rising temperatures. The tensile strength of PLA/CF geogrids was significantly better than PLAgeogrids. Due to the addition of carbon fiber in PLA, PLA/CF can bear more tensile force at high temperatures. With theincrease of temperature, the elongation at break of PLA/CF geogrids and fiberglass geogrids increased, but the elongation atbreak of PLA geogrids decreased. The elongation at break of PLA/CF geogrids was significantly lower than that of PLAgeogrids. TPU geogrids had high tensile capacity in a high-temperature environment, and they also had high elasticity andmore significant elongation at break, which was not suitable to be used as geogrid material.

Simultaneous Determination of Mycophenolic Acid and Its Metabolites by HPLC and Pharmacokinetic Studies in Rat Plasma and Bile

Jun-wei Gao,Zhi-hai Peng,Xiao-yu Li,Bo Sun,Yan-kun Guo,Gao-lin Liu 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.1

In this study, we determined the pharmacokinetics of mycophenolic acid (MPA) and its metabolites mycophenolic acid glucuronide (MPAG) and acyl glucuronide (AcMPAG) in rat plasma and bile, using a newly developed HPLC method. Protein precipitation and liquid-liquid extraction were employed in sample preparation of plasma and bile, respectively. The HPLC methods included a gradient elution consisting of acetonitrile and phosphate buffer at a flow rate of 1.2 mL/min, with UV detection at 254 nm. The HPLC method was found to be sensitive and linear (r^2 ≥ 0.9991, 1.0-128.0 and 0.25-32.0 mg/L for MPA; 1.0-128.0 and 0.5-64.0 mg/L for MPAG; 0.25-32.0 and 1.0-128.0 mg/L for AcMPAG in rat plasma and bile, respectively), precise (both the intra- and inter-day variability were ≤ 6.8%), and accurate (both the intra- and inter-day accuracy were between 92.2% and 105.4%). The average extraction efficiencies for MPA, MPAG and AcMPAG were 85.3%, 100.1%, and 94.7% in plasma, and 88.0%, 67.3%, and 68.3% in bile, respectively. The method was successfully employed for pharmacokinetic studies in plasma and bile after oral administration of mycophenolate mofetil (prodrug of MPA) in rats.

Effects of Upwelling/Downwelling on Suspended Particulate Matter Distributions over Shelf Mud Areas: Numerical Experiments

Gao, Shu,Jia, Jian-Jun The Korean Society of Oceanography 2002 Journal of the Korean Society of Oceanography Vol.37 No.3

The mud deposit located to the south of Cheju Island, the East China Sea, is characterized by an upwelling system or, on occasions, a combined upwelling-downwelling system. The water mass here is associated with relatively high suspended matter concentrations. In the present study, a vertical I-D model is used to undertake numerical experiments for evaluating the upwelling and downwelling effects on the suspended particulate matter distribution patterns within the water column. The results show that: (1) because the upwelling or downwelling velocity tends to be of the same order of magnitude as the settling velocity of suspended particles, a number of different patterns of suspended matter concentration distribution are possible, depending on the relative importance of the velocities; (2) the presence of upwelling can enhance the suspended particulate matter concentration; and (3) in an upwelling-downwelling system, maximum concentrations may or may not lie in the middle of the water column, depending on, once again, the interrelationships between the opwelling/downwelling velocities and the settling velocity. Hence, the physical processes associated with upwelling/downwelling appear to be relevant to the suspended material distribution over shelf mud areas.

Application of GEP Algorithm in Prediction of Subgrade Settlement

Gao Hui,Huang Jun 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.9

Application of Twin Support Vector Regression in Subgrade Settlement Prediction

Gao Hui,Song Qi-chao,Huang Jun 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.7

Due to the normal forecasting methods for subgrade settlement using observation data have different applicabilities, and the predicting results has bigger volatility and lower accuracy. In view of the above problems, based on the twin support vector regression tool, the settlement prediction model is established by combining with the measured roadbed settlement data; The related parameters of the prediction model are given and compared with the standard support vector regression machine, the comparison tests show that the twins support vector regression is a new method to predict the settlement of the roadbed, and is superior in forecasting accuracy to the standard support vector regression.

Association of microRNA-3144 variant with the susceptibility to hepatocellular carcinoma

Jun Zhang,Yi Liu,Jie Liu,Rui Wang,Min Cai,Shunji Yu,Yanyun Ma,Weihong Xu,Chunfang Gao,Jiucun Wang,Lifang Hou 한국유전학회 2014 Genes & Genomics Vol.36 No.6

Increasing studies suggest that microRNAs, anew group of small non-coding molecules, regulate theexpression of their target genes and play some roles in cancers. Thus, it is hypothesized that the genetic variants ofmicroRNAs could contribute to the susceptibility to cancers. In this study, the association between rs67106263 in microRNA-3144 and the risk of hepatocellular carcinoma (HCC)was explored in a large-scaled case–control population basedon MassARRAY technology. It was discovered that comparedwith the carriers of wide-type GG genotype and heterozygoteGA genotype of microRNA-3144, thesignificantly increased risk of HCC was observed in thesubjects with the homozygote variant AA (adjusted oddsratio = 1.285, 95 % confidence interval = 1.004–1.643,P = 0.046). Additionally, the variant was also associatedwith the expression of alpha fetoprotein (AFP), which is thediagnostic marker for HCC. Our findings suggest for the firsttime that rs67106263 may play some roles in the risk of HCC,expecting future molecular researches to elucidate the possiblemechanisms behind these results.

Spin reorientation of Fe films studied by the magneto-optical Kerr effect

Jun Ye,Qing-Yuan Jin,Bin Ma,Chun-Lei Gao,Yuan Zhao 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.32

The ability to alter magnetic anisotropy values is of technological importance in the application of magnetic ultrahigh-density recording. By capping some other atoms onto the surface of a magnetic thin lm or inserting a thin layer between the magnetic lm and the substrate, we can change the surface or interface perpendicular magnetic anisotropy and then alter the magnetic properties of the lm, such as the spin reorientation transition (SRT), in ultrathin ferromagnetic lms. The SRT of face-centered-tetragonal (fct) Fe lms grown on Cu(001) substrate is determined by the magneto-optical Kerr eect. We nd that the out-of-plane magnetization changes to in-plane induced by a Ni-capping or a Co-inserting layer at 110 K. From the linear relation of the critical thickness of a fct-Fe lm with Ni or Co covering when SRT occurs, the \true" critical thickness of the pure fct-Fe lm without coverage or buer in the absence of structural transformation is obtained by setting the coverage to zero value. The estimated true critical thickness is approximately 4.3 ML for the Ni-capping method and 4.6 ML for the Co-inserting experiment, which are very close to the reported result for the Co-capping experiment.

Combined Forecasting Model of Subgrade Settlement Based on Least Square Twin Support Vector Regession

GAO Hui,Song Qi-chao,Huang Jun 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.6

Due to the normal forecasting methods for subgrade settlement using observation data have different applicabilities, and the predicting results has bigger volatility and lower accuracy. The Combined forecasting model of subgrade settlement based on Least Square twin support vector regession is put forward in this paper. At the first, according to the basic settlement law of subgrade and characteristics of settlement curve, the growth curve with the S-type characteristics are choosed as single forcasting model; Then taking prediction results of each individual model as the least square support vector regression model input and to construct the combined forecasting model of subgrade settlement. The result of engineering practice shows that the proposed method has better prediction accuracy and stability.

Design and Experiments of a Linear Motor with High-speed and High-thrust Force for the replacement of hydraulic actuator

Jun Gao(고준),J.H. Choi(최종현),Y.S. Kueon(권영섭),Y.S. Baek(백윤수) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11

Hydraulic actuators are normally used in the systems requiring a large amount of motive force. However, when the system requires high frequency and fast response, it is hard to control the actuator which is shown to have low mechanical performance. Therefore direct-driven electromagnetic linear actuator system is demanded. This paper deals with a linear motor system which is replaced to achieve direct linear motion. The modeling has been done with Finite Element(FE) Analysis and two prototypes have been designed and fabricated. They are designed with moving-coil and moving-magnet type. Halbach array is used on the second type to reduce detent force. In this study, FE analytical results are validated by experiments. The results show that thrust force is about 6,000N and detent force is reduced to approximately 35N. The linear motor system presented in the work can be used for other devices, just like machine-tool sliding tables, continuous casters and so on.

Ethanol but not Aqueous Extracts of Tubers of Sauromatum Giganteum(Engl.) Cusimano and Hett Inhibit Cancer Cell Proliferation

Gao, Shi-Yong,Li, Jun,Wang, Long,Sun, Qiu-Jia,Gong, Yun-Fei,Gang, Jian,Su, Yi-Jun,Ji, Yu-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

Background: Both alcohol and aqueous extracts of Sauromatum giganteum(Engl.) Cusimano and Hett, the dried root tuber of which is named Baifuzi in Chinese, have been used for folklore treatment of cancer in Northeast of China. However, little is known about which is most suitable to the cancer therapy. Materials and Methods: Serum pharmacology and MTT assays were adopted to detect the effects of ethanol and aqueous extracts of Sauromatum giganteum(Engl.) Cusimano and Hett, prepared by heat reflux methods, on proliferation of different cancer cells. Results: Cancer cells treated with medium supplemented with 10%, 20%, 40% serum(v/v) containing ethanol extract had a decline in viability, with inhibition rates of 7.69%, 21.8%, 41.9% in MCF-7 cells, 42.8%, 48.1%, 51.8% in SGC-7901 cells, 44.1%, 49.2%, 53.7% in SMMC-7721 cells, 6.8%, 15.2%, 39.8% in HepG2 cells, 7.57%, 16.3%, 36.2% in HeLa cells, 6.24%, 12.5%, 27.4% in A549 cells, and 7.20%, 17.5%, 31.3% in MDA-MB-231 cells, respectively. Viability in the aqueous extract groups was no different with that of controls. Conclusions: An ethanol extract of Sauromatum giganteum(Engl.) Cusimano and Hett inhibited the proliferation of SMMC-7721, SGC-7901 and MCF-7 cells, which supports the use of alcoholic but not aqueous extracts for control of sensive cancers, which might include hepatocarcinoma, gastric cancer and breast cancer.