Effect of Temperature on Resistivity of CFRP Materials with Added Carbon Powder or Nano-silica

Dan Liu,Jie Yin,Rong-gui Liu,Shu Ping,Hui-guang Yin,Gui-hua Xie 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.4

This paper presents an experimental investigation on the effect of temperature on resistivity of Carbon Fiber Reinforced Polymer (CFRP) materials. A series of tests were conducted on three types of CFRP materials, namely pure CFRP material, CFRP with carbon powder (4% in weight) and CFRP with nano-silica (4% in weight). Test results showed that adding carbon powder into the epoxy resin decreases the initial electric resistance R0 and initial volume resistivity ρ0 while adding nano-silica increases R0 and ρ0 compared to pure CFRP material. Preheating cycle test results showed that the volume resistivity of all three types of specimens linearly increases with increasing temperature. CFRP with added nano-silica exhibits higher temperature sensitivity than CFRP with added carbon powder compared to the lowest temperature sensitivity for pure CFRP material. In addition, temperature cycle test results showed that CFRP specimens have approximately stable values of volume resistivity. Both CFRP specimens with added carbon powder or nano-silica exhibit a recognizable trend of first decrease and then increase in volume resistivity with increasing temperature both during heating and cooling cycles. CFRP with added carbon powder mainly shows Negative Temperature Coefficient (NTC) effect in the temperature range of −40 to 40oC and Positive Temperature Coefficient (PTC) effect from 40 to 80oC. CFRP with added nano-silica mainly exhibits PTC effect in the temperature domain of −15 to 80oC and NTC effect from −40 to −15oC. A mathematical-physical model with respect to the thermal effect was presented based on the Eshelby-Mori-Tanaka (EMT) approach and mesomechanics method. The results obtained with the model agree well with the test results considering the temperature domain of PTC effect, which indicates that the proposed model is effective in characterizing the variation of fractional change in resistance (ΔR/R0) at varying temperature.

Study on Large Straight Blade Wide Impeller

Qi Chun Song,Dan Hui Jie,Yang Yang Zhe,Dong Kang Tian 대한기계학회 1997 International Conference on Fluid Machinery Vol.1 No.1

Numerical Study of the Effect of Grout Material Properties on Ground Deformation during Shallow TBM Tunneling

Qi Zhang,Xiao-Ping Zhang,Hao-Jie Wang,Quan-Sheng Liu,Dan Xu,Shao-Hui Tang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.8

The full-face shield tunnel boring machine (TBM) has been widely used to build tunnels in urban area. Ground deformations usually occur during tunnelling processes, which is closely related to engineering geological property. A large ground deformation may lead to large-scale surface settlement or ground collapse, especially for shallow buried tunnels. In general, synchronous grouting is adopted to reduce the ground deformation. The temporal and spatial distribution of the grout pressure and consolidation processes of grouting have a significant influence on the deformation. For a better understanding the relationship between the grout material type and the ground deformation, the present study models a complex numerical model in FLAC3D based on the Guangzhou Metro line 18. A numerical method is proposed to reproduce the tunnelling process and the consolidation process of grout material. The effect of grouting material on ground deformation is discussed, i.e., immediately solidified type, quick hardening type, and good mobility type. The ground deformation of the numerical simulation are compared to those monitored in the field. The results indicate that the immediately solidified type grout can reduce the ground settlement effectively and is mainly applicable to secondary grouting. The quick hardening type can make the ground upheaval, which is smaller than that induced by immediately solidified type. The good mobility type can reduce the ground settlement and well control the ground deformation. The good mobility type recommends using in the numerical study for simulating the synchronous grouting.

Single Nucleotide Polymorphisms of the GnRHR Gene Associated with Reproductive Traits of Japanese Flounder (Paralichthys olivaceus)

He, Feng,Wen, Hai-Shen,Li, Ji-Fang,Yu, Da-Hui,Ma, Rui-Qin,Shi, Dan,Mu, Wei-Jie,Zhang, Yuan-Qing,Hu, Jian,Liu, Miao,Han, Wei-Guo,Zhang, Jia-Nan,Wang, Qing-Qing,Yuan, Yu-Ren,Liu, Qun Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.4

Gonadotropin-releasing hormone receptor (GnRHR) gene is expressed at the anterior pituitary gland and plays a key role in gonad development. This study aimed to investigate molecular genetic characteristics of the GnRHR gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of GnRHR gene on sex steroid level in Japanese flounder (Paralichthys olivaceus). We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the GnRHR gene in 75 individuals. We identified three SNPs in the GnRHR gene: P1 locus (C759A and C830T) in the coding region of exon2 which were both linked together and P2 locus (G984T) in the coding region of exon3, which added a new transcript factor (ADR1) and a new methylation site (CG). Only C830T of P1 leads to amino acid changes Thr266Ile. Statistical analysis showed that P1 was significantly associated with $17{\beta}$-estradiol ($E_2$) level (p<0.01) and gonadosomatic index (GSI) (p<0.05). Individuals with genotype BB of P1 had significantly higher serum $E_2$ levels (p<0.01) and GSI (p<0.05) than those of genotype AA or AB. Another SNP, P2, synonymous mutation, was significantly associated with GSI (p<0.05). Individuals with genotype AB of P2 had significantly higher GSI (p<0.05) than that of genotype AA. In addition, there was a significant association between one diplotype based on three SNPs and reproductive traits. The genetic effects for both serum $E_2$ level and GSI of diplotype D4 were super diplotypes (p<0.05). These results suggest that the SNPs in Japanese Flounder GnRHR are associated with $E_2$ level and GSI.

Systemic Inflammatory Biomarkers, Especially Fibrinogen to Albumin Ratio, Predict Prognosis in Patients with Pancreatic Cancer

Lin Fang,Fei-Hu Yan,Chao Liu,Jing Chen,Dan Wang,Chun-Hui Zhang,Chang-Jie Lou,Jie Lian,Yang Yao,Bo-Jun Wang,Rui-Yang Li,Shu-Ling Han,Yi-Bing Bai,Jia-Ni Yang,Zhi-Wei Li,Yan-Qiao Zhang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.1

Purpose Systemic inflammatory response is a critical factor that promotes the initiation and metastasis of malignancies including pancreatic cancer (PC). This study was designed to determine and compare the prognostic value of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and fibrinogen-to-albumin ratio (FAR) in resectable PC and locally advanced or metastatic PC. Materials and Methods Three hundred fifty-three patients with resectable PC and 807 patients with locally advan-ced or metastatic PC were recruited in this study. These patients were classified into a training set (n=758) and a validation set (n=402). Kaplan-Meier survival plots and Cox proportional hazards regression models were used to analyze prognosis. Results Overall survival (OS) was significantly better for patients with resectable PC with low preoperative PLR (p=0.048) and MLR (p=0.027). Low FAR, MLR, NLR (p < 0.001), and PLR (p=0.003) were significantly associated with decreased risk of death for locally advanced or metastatic PC patients. FAR (hazard ratio [HR], 1.522; 95% confidential interval [CI], 1.261 to 1.837; p < 0.001) and MLR (HR, 1.248; 95% CI, 1.017 to 1.532; p=0.034) were independent prognostic factors for locally advanced or metastatic PC. Conclusion The prognostic roles of FAR, MLR, NLR, and PLR in resectable PC and locally advanced or metastatic PC were different. FAR showed the most prognostic power in locally advanced or metastatic PC. Low FAR was positively correlated with OS in locally advanced or metastatic PC, which could be used to predict the prognosis.

Association between RASSF1A Promoter Hypermethylation and Oncogenic HPV Infection Status in Invasive Cervical Cancer: a Meta-analysis

Li, Jin-Yun,Huang, Tao,Zhang, Cheng,Jiang, Dan-Jie,Hong, Qing-Xiao,Ji, Hui-Hui,Ye, Meng,Duan, Shi-Wei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Cervical carcinoma is the main cause of cancer-related mortality in women and is correlated with more than 15 risk cofactors, including infection of cervical cells with high-risk types of HPV (hrHPV). Indeed, both aberrant methylation of the RASSF1A promoter and hrHPV infection are often observed in cervical carcinomas. The purpose of our meta-analysis was to evaluate the role of RASSF1A promoter methylation and hrHPV infection in cervical cancer. Our meta-analysis involved 895 cervical cancer patients and 454 control patients from 15 studies. Our results suggested that RASSF1A promoter hypermethylation increased the risk of cervical cancer (OR=9.77, 95%CI=[3.06, 31.26], P=0.0001, $I^2=78%$). By grouping cases according to cancer subtypes, we found that HPV infection was higher in cervical squamous cell carcinomas (SCCs) than in cervical adenocarcinomas/adenosquamous cancers (ACs/ASCs) (OR=4.00, 95%CI=[1.41, 11.30], P=0.009, $I^2=55%$). Interestingly, HPV infection tended to occur in cervical cancers with relatively low levels of RASSF1A promoter methylation (OR=0.59, 95%CI=[0.36, 0.99], P=0.05, I2=0%). Our study provides evidence of a possible interaction between HPV infection and RASSF1A promoter methylation in the development of cervical cancers.