Lifetime Prediction and Aging Behaviors of Nitrile Butadiene Rubber under Operating Environment of Transformer

Qian, Yi-hua,Xiao, Hong-zhao,Nie, Ming-hao,Zhao, Yao-hong,Luo, Yun-bai,Gong, Shu-ling The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Based on the actual operating environment of transformer, the aging tests of nitrile butadiene rubber (NBR) were conducted systematically under four conditions: in air, in transform oil, under compression in air and under compression in transform oil to studythe effect of high temperature, transform oil and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber and predict the lifetime. The effects of liquid media and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber were studied by using characterization methods such as IR spectrosc-opy, thermogravimetric measurements, Differential Scanning Calorimetry (DSC) measurements and mechanical property measurements. The changes in physical properties during the aging process were analyzed and compared. Different aging conditions yielded materials with different properties. Aging at $70^{\circ}C$ under compression stress in oil, the change in elongation at break was lower than that aging in oil, but larger than that aging under compression in air. The compression set or elongation at break as evaluation indexes, 50% as critical value, the lifetime of NBR at $25^{\circ}C$ was predicted and compared. When aging under compression in oil, the prediction lifetime was lower than in air and under compression in air, and in oil. It was clear that when predicting the service lifetime of NBR in oil sealing application, compression and media liquid should be involved simultaneously. Under compression in oil, compression set as the evaluation index, the prediction lifetime of NBR was shorter than that of elongation at break as the evaluation index. For the life prediction of NBR, we should take into account of the performance trends of NBR under actual operating conditions to select the appropriate evaluation index.

Lifetime Prediction and Aging Behaviors of Nitrile Butadiene Rubber under Operating Environment of Transformer

Yi-hua Qian,Hong-zhao Xiao,Ming-hao Nie,Yao-hong Zhao,Yun-bai Luo,Shu-ling Gong 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Based on the actual operating environment of transformer, the aging tests of nitrile butadiene rubber (NBR) were conducted systematically under four conditions: in air, in transform oil, under compression in air and under compression in transform oil to studythe effect of high temperature, transform oil and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber and predict the lifetime. The effects of liquid media and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber were studied by using characterization methods such as IR spectrosc-opy, thermogravimetric measurements, Differential Scanning Calorimetry (DSC) measurements and mechanical property measurements. The changes in physical properties during the aging process were analyzed and compared. Different aging conditions yielded materials with different properties. Aging at 70°C under compression stress in oil, the change in elongation at break was lower than that aging in oil, but larger than that aging under compression in air. The compression set or elongation at break as evaluation indexes, 50% as critical value, the lifetime of NBR at 25°C was predicted and compared. When aging under compression in oil, the prediction lifetime was lower than in air and under compression in air, and in oil. It was clear that when predicting the service lifetime of NBR in oil sealing application, compression and media liquid should be involved simultaneously. Under compression in oil, compression set as the evaluation index, the prediction lifetime of NBR was shorter than that of elongation at break as the evaluation index. For the life prediction of NBR, we should take into account of the performance trends of NBR under actual operating conditions to select the appropriate evaluation index.

Lifetime Prediction and Aging Behaviors of Nitrile Rubber Under Operating Environment of Transformer

Yi-Hua Qian,Hong-zhao Xiao,Ming-hao Nie,Yao-hong Zhao,Yunbai Luo,Shu-ling Gong 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Based on the actual operating environment of transformer, the aging tests of nitrile butadiene rubber (NBR) were conducted systematically under four conditions: in air, in transform oil, under compression in air and under compression in transform oil to studythe effect of high temperature, transform oil and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber and predict the lifetime. The effects of liquid media and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber were studied by using characterization methods such as IR spectrosc-opy, thermogravimetric measurements, Differential Scanning Calorimetry (DSC) measurements and mechanical property measurements. The changes in physical properties during the aging process were analyzed and compared. Different aging conditions yielded materials with different properties. Aging at 70°C under compression stress in oil, the change in elongation at break was lower than that aging in oil, but larger than that aging under compression in air. The compression set or elongation at break as evaluation indexes, 50% as critical value, the lifetime of NBR at 25°C was predicted and compared. When aging under compression in oil, the prediction lifetime was lower than in air and under compression in air, and in oil. It was clear that when predicting the service lifetime of NBR in oil sealing application, compression and media liquid should be involved simultaneously. Under compression in oil, compression set as the evaluation index, the prediction lifetime of NBR was shorter than that of elongation at break as the evaluation index. For the life prediction of NBR, we should take into account of the performance trends of NBR under actual operating conditions to select the appropriate evaluation index.

Effects of Lactobacillus plantarum SCS2 on blood glucose level in hyperglycemia mice model

Xiao Meng,Yu Qian,Li-Shi Jiang,Jin-Mei Kang,Yan Chen,Juan Wang,Shu-Kun Liu,Zhen-Ming Che,Xin Zhao 한국응용생명화학회 2016 Applied Biological Chemistry (Appl Biol Chem) Vol.59 No.1

In this study, the hyperglycemia mice model was established with 1-week high sugar and fat diet plus with 70 mg/kg body weight of streptozotocin injection for 3 days. Sixty male Kunming mice of 3 weeks old in a specific-pathogen-free grade were divided into six groups randomly, which includes normal group (NG), prevention group (PG), treatment group for low dose (TGL), middle dose (TGM), high dose (TGH), and model group (MG). NG and MG mice were fed with sterile physiological saline (10 mL/kg body weight). PG mice were fed with the concentration of 6.0 × 109 CFU/mL L. plantarum SCS2 suspensions from the second to third week. TGL, TGM, and TGH mice were fed with the concentration of 2.0 × 109, 4.0 × 109, and 6.0 × 109 CFU/mL L. plantarum SCS2 suspensions (10 mL/kg body weight), respectively from fourth to tenth week. The results showed that the fasting and postprandial 2 h blood glucose levels of TGH mice were reduced by L. plantarum SCS2 significantly (p < 0.05) as compared with MG. The body weight of TGH mice came to normal level at tenth week. Content of K+ in plasma of TGH mice was increased and contents of Na+ and Cl− in the plasma of TGH mice were decreased as compared with MG. Meanwhile, content of glycogen in TGH mice was reduced. However, the effect of L. plantarum SCS2 on the prevention of hyperglycemia in PG mice was not significant as compared with NG mice during the experiment. These results suggested that L. plantarum SCS2 showed a hypoglycemic effect on hyperglycemic mice model.

A Circuit Simulation Model for An Uitra-fast IGBT And Analysis of Parameter Sensitivity

Ai-min Li,Xiang-ning He,Zhao-ming Qian 전력전자학회 1995 ICPE(ISPE)논문집 Vol.1995 No.10

Based on existing built-in models of PSpice, by the composite model principle, a composite Insulated Gate Bipolar Transistor (IGBT) model for an ultra-fast IGBT is presented Comparison between measurement and simulation results shows good agreement in transient and steady-state behaviour of the IGBT Parametric sentive analysis of this model is performed, and validity of the composite model is discussed.

Genetic Variants of NBS1 Predict Clinical Outcome of Platinum-based Chemotherapy in Advanced Non-small Cell Lung Cancer in Chinese

Xu, Jia-Li,Hu, Ling-Min,Huang, Ming-De,Zhao, Wan,Yin, Yong-Mei,Hu, Zhi-Bin,Ma, Hong-Xia,Shen, Hong-Bing,Shu, Yong-Qian Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Objective: NBS1 plays a key role in the repair of DNA double-strand break (DSB). We conducted this study to investigate the effect of two critical polymorphisms (rs1805794 and rs13312840) in NBS1 on treatment response and prognosis of advanced non-small cell lung cancer (NSCLC) patients with platinum-based chemotherapy. Methods: Using TaqMan methods, we genotyped the two polymorphisms in 147 NSCLC patients. Odds ratios (ORs) and their 95% confidential intervals (CIs) were calculated as a measure of difference in the response rate of platinum-based chemotherapy using logistic regression analysis. The Kaplan-Meier and log-rank tests were used to assess the differences in progression-free survival (PFS) and overall survival (OS). Cox proportional hazards model was applied to assess the hazard ratios (HRs) for PFS and OS. Results: Neither of the two polymorphisms was significantly associated with treatment response of platinum-based chemotherapy. However, patients carrying the rs1805794 CC variant genotype had a significantly improved PFS compared to those with GG genotype (16.0 vs. 8.0 months, P = 0.040). Multivariable cox regression analysis further showed that rs1805974 was a significantly favorable prognostic factor for PFS [CC/CG vs. GG: Adjusted HR = 0.62, 95% CI: 0.39-0.99; CC vs. CG/GG: Adjusted HR = 0.56, 95% CI: 0.32-0.97). Similarly, rs13312840 with a small sample size also showed a significant association with PFS (CC vs. CT/TT: Adjusted HR = 25.62, 95% CI: 1.53-428.39). Conclusions: Our findings suggest that NBS1 polymorphisms may be genetic biomarkers for NSCLC prognosis especially PFS with platinum-based chemotherapy in the Chinese population.

Efficacy and Survival-associated Factors with Gefitinib Combined with Cisplatin and Gemcitabine for Advanced Non-small Cell Lung Cancer

Fang, Hong,Lin, Rong-Yan,Sun, Ming-Xia,Wang, Qian,Zhao, Yu-Liang,Yu, Jing-Lin,Tian, Yan,Wang, Xiao-Yun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

Objective: To analyze the efficacy and survival associated factors of gefitinib combined with cisplatin and gemcitabine for advanced non-small cell lung cancer. Materials and Methods: A total of 57 patients with advanced non-small cell lung cancer (NSCLC), who received platinum-based chemotherapy regimens for more than 1 cycle, were treated with gefitinib combined with cisplatin and gemcitabine until disease progression. Efficacy, survival time and adverse reactions were observed. The Kaplan-Meier method was adopted for analysis of survival and Cox regression for associated influencing factors. Results: The patients were followed up until October 31, 2013, and the median follow-up time was 19 months. Of 57 patients, there were 4 (7.0%) with complete remission (CR), 8 (14.0%) with partial remission, 31 (54.4%) with stable disease, and 14 (24.6%) with disease progression. The remission rate was 21.1% and the disease control rate was 75.4%. The median progression-free survival (PFS) time and the median overall survival time were 10 months and 15.2 months. The one-year, two-year and three-year survival rates were 47.4%, 23.3% and 10.0%. Gender and pathological types were the independent risk factors influencing PFS time (P=0.028, P=0.009). Tumor pathological type and early efficacy were independent factors for the prognosis (P=0.018, P=0.000). Adverse reactions were mostly rashes of I~II degree and diarrhea and slightly increasing level of aminopherase. The skin adverse event incidence of III degree or above was 1.8% (1/57) and brain metastasis was foudn in 31.6% (18/57). Conclusions: Gefitinib combined with cisplatin andgemcitabine, is effective for patients with IIIb~IV NSCLC who received multiple cycles of chemotherapy.

An Increase in Synaptic NMDA Receptors in the Insular Cortex Contributes to Neuropathic Pain

Qiu, Shuang,Chen, Tao,Koga, Kohei,Guo, Yan-yan,Xu, Hui,Song, Qian,Wang, Jie-jie,Descalzi, Giannina,Kaang, Bong-Kiun,Luo, Jian-hong,Zhuo, Min,Zhao, Ming-gao AAAS 2013 Science signaling Vol.6 No.275

<P><B>Stopping the Pain</B></P><P>Damage to the central or peripheral nervous system can trigger the development of neuropathic pain, which can manifest as painful sensations in response to stimuli that are not normally painful. Qiu <I>et al.</I> found that mice that had developed neuropathic pain after peripheral nerve injury showed changes in synaptic plasticity and increased abundance of synaptic NMDA receptors in the insular cortex, a region of the brain that is activated by acute and chronic pain. Using pharmacological inhibitors and transgenic mice, they mimicked these changes in vitro with insular cortical slices and thus identified the signaling pathway responsible. Mice injected with NMDA receptor inhibitors showed reduced behavioral signs of neuropathic pain after peripheral nerve injury. Thus, blocking NMDA receptor function in the insular cortex may prevent the development of neuropathic pain.</P>

Effect of Different Nanofillers on Non-Isothermal Crystallization Kinetics and Electric Conductivity of Dynamically-Vulcanized PP-EPDM Blends

Bin Yang,Lei Hu,Ru Xia,Fang Chen,Shu-Chun Zhao,Yan-Li Deng,Ming Cao,Jiasheng Qian,Peng Chen 한국고분자학회 2016 Macromolecular Research Vol.24 No.1

In this study, nanofillers composed of hydroxylated carbon nanotubes (h-CNT), carbon nanotubes (CNT) and graphene (GR) were separately added into the dynamically-vulcanized polypropylene (PP)/ethylene-propylenediene monomer (EPDM) blend. Differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and electrical resistivity measurements were employed to study the effect of nanofillers on the melt behavior, non-isothermal crystallization behavior and electrical conductivity of the prepared composites. WAXD results showed that h-CNT had a better induction effect of β-PP in the nanocomposites. The sequence of the activity in inducing the formation of β-PP was h-CNT>GR>CNT. However, the total crystallinity of the nanocomposites nearly remained constant. Non-isothermal crystallization kinetic analysis indicated that the presence of nanofillers improved the crystallization rate of the nanocomposites. The consequence of nucleation activity was as follows: CNT>GR>h-CNT. Although EPDM hindered the macromolecular motion of PP, interestingly it could increase the crystallization rate to an extent. Besides, the influence of nanofillers on enhancing the conductive property of the nanocomposites can be ranked as follow: CNT>GR>h-CNT.

The Prognostic Value of Treatment-Related Lymphopenia in Nasopharyngeal Carcinoma Patients

Li-Ting Liu,Qiu-Yan Chen,Lin-Quan Tang,Shan-Shan Guo,Ling Guo,Hao-Yuan Mo,Ming-Yuan Chen,Chong Zhao,Xiang Guo,Chao-Nan Qian,Mu-Sheng Zeng,Jin-Xin Bei,Jing Tan,Shuai Chen,Ming-Huang Hong,Jian-Yong Shao 대한암학회 2018 Cancer Research and Treatment Vol.50 No.1

Purpose This study was conducted to evaluate the prognostic value of treatment-related lymphopenia in patients with nasopharyngeal carcinoma (NPC). Materials and Methods A total of 413 consecutive stage II-IVb NPC patients treated with concurrent chemoradiotherapy (CCRT) were enrolled. The overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. Results A minimum (mini)–absolute lymphocyte counts (ALC) of < 390 cells/μL or ALC after 3 months of CCRT (post3m-ALC) < 705 cells/μL was significantly associated with worse outcome than mini-ALC ! 390 cells/μL (OS, p=0.002; PFS, p=0.005; DMFS, p=0.004) or post3m-ALC ! 705 cells/μL (OS, p < 0.001; PFS, p < 0.001; DMFS, p=0.001). Patients with lymphopenia (mini-ALC < 390 cells/μL and post3m-ALC < 705 cells/μL) had a worse prognosis than those without lymphopenia (mini-ALC ! 390 cells/μL and post3m-ALC ! 705 cells/μL) (OS, p < 0.001; PFS, p < 0.001; DMFS, p < 0.001). Multivariate analysis revealed that post3m-ALC was an independent prognostic factor for OS (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.12 to 2.78; p=0.015), PFS (HR, 1.86; 95% CI, 1.23 to 2.82; p=0.003), and DMFS (HR, 1.87; 95% CI, 1.13 to 3.08; p=0.014). Multivariate analysis also revealed that patients with lymphopenia had a high risk of death (HR, 3.79; 95% CI, 1.75 to 8.19; p=0.001), disease progression (HR, 2.93; 95% CI, 1.59 to 5.41; p=0.001), and distant metastasis (HR, 3.89; 95% CI, 1.67 to 9.10; p=0.002). Multivariate analysis performed with time dependent Cox regression demonstrated ALC was an independent prognostic factor for OS (HR, 0.995; 95% CI, 0.991 to 0.999; p=0.025) and PFS (HR, 0.993; 95% CI, 0.988 to 0.998; p=0.006). Conclusion Treatment-related lymphopenia was a poor prognostic factor in NPC patients.