http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Li, Da-Peng,Du, Chen,Zhang, Zuo-Ming,Li, Guang-Xiao,Yu, Zhi-Fu,Wang, Xin,Li, Peng-Fei,Cheng, Cheng,Liu, Yu-Peng,Zhao, Ya-Shuang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12
The present systematic review and meta-analysis was conducted to assess any association between breastfeeding and the risk of ovarian cancer. A systematic search of published studies was performed in PUBMED and EMBASE and by reviewing reference lists from retrieved articles through March 2013. Data extraction was conducted independently by two authors. Pooled relative risk ratios were calculated using random-effect models. Totals of 5 cohort studies and 35 case-control studies including 17,139 women with ovarian cancer showed a 30% reduced risk of ovarian cancer when comparing the women who had breastfed with those who had never breastfed (pooled RR = 0.70, 95% CI: 0.64-0.76; p = 0.00), with significant heterogeneity in the studies (p = 0.00; I2 = 76.29%). A significant decreasd in risk of epithelial ovarian cancer was also observed (pooled RR = 0.68, 95% CI: 0.61-0.76). When the participants were restricted to only parous women, there was a slightly attenuated but still significant risk reduction of ovarian cancer (pooled RR = 0.76, 95% CI: 0.69-0.83). For total breastfeeding duration, the pooled RRs in the < 6 months, 6-12 months and > 12 months of breastfeeding subgroups were 0.85 (95% CI: 0.77-0.93), 0.73 (95% CI: 0.65-0.82) and 0.64 (95%CI: 0.56-0.73), respectively. Meta-regression of total breastfeeding duration indicated an increasing linear trend of risk reduction of ovarian cancer with the increasing total breastfeeding duration (p = 0.00). Breastfeeding was inversely associated with the risk of ovarian cancer, especially long-term breastfeeding duration that demonstrated a stronger protective effect.
Oxidation behavior of YAG-ZrB2 ceramics prepared by spark plasma sintering
Jie-Guang Song,Da-Ming Du,Yin-Yan Ju,Yang-Liang Li,Shi-Bin Li,Gang-Chang Ji 한양대학교 세라믹연구소 2010 Journal of Ceramic Processing Research Vol.11 No.4
ZrB2 and YAG are widely applied because of some excellent properties, but ZrB2 is easily oxidized in high-temperature air. To make ZrB2 ceramics have better oxidation resistance, high-density YAG-ZrB2 ceramics were prepared. The oxidation behavior of YAG-ZrB2 ceramics is investigated at different temperatures. The results indicate that the enhanced weight change differs according to the temperature range, slightly in the temperature 900-1000oC, sharply from 1100-1300 and smoothly above 1300oC. The weight change rate of YAG-ZrB2 ceramics is increased by prolonging the oxidation time, but the weight change rate of YAG-ZrB2 ceramics is gradually reduced. The oxidation layer is porous as compared to the YAG-ZrB2 ceramics layer.
Effect of raw materials on the properties of ZrB2-YAG-Al2O3 multi-phase ceramics
Jie-Guang Song,Fang Wang,Da-Ming Du,Yin-Yan Ju,Shi-Bin Li,Gang-Chang Ji,Lian-Meng Zhang 한양대학교 세라믹연구소 2014 Journal of Ceramic Processing Research Vol.15 No.2
ZrB2 belongs to a class of ceramics defined ultra-high-temperature ceramics with extremely high melting temperatures, but ZrB2 ceramics is difficultly sintered and easily oxidized. To make ZrB2 ceramics possess the high relative density and the better oxidation resistance. The effects of raw materials on the properties of ZrB2 composite were investigated. YAG and Al2O3 help for the densification of ZrB2 ceramics. Fracture toughness of sintered ceramics with coated powder is higher than that of sintered ceramics with mixed powder. The mechanical property of ZrB2-YAG-Al2O3 materials is higher than that of ZrB2-YAG materials. Oxidation layer thickness of sintered ceramics with coated powder is thinner than that of sintered ceramics with mixed powder. These results show the sintered ZrB2 based multi-phase ceramics with coated microstructure help to increase the mechanical properties and oxidation resistance. The oxidation resistance of ZrB2-YAG-Al2O3 ceramics is better than that of ZrB2-YAG materials.
Jie-Guang Song,Min-Han Xu,Da-Ming Du,Fang Wang,Shi-Bin Li,Gang-Chang Ji 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.4
Zirconium diboride is widely applied because of some excellent properties. The effect of the oxidation temperature on the surface microdomain of ZrB2-YAG multi-phase ceramics was studied, it helps to improve the performance of ultra-hightemperature ceramics. The results show the oxidation layer thickness is increased with an increase in the oxidation temperature, the oxidation layer thickness is decreased by increasing the density of multi-phase ceramics at the same oxidation temperature. The ceramic surface shows the (m)ZrO2, YAG, B2O3 and ZrB2 phases below the the oxidation temperature at 1300 ο C, but the ceramic surface do not show the ZrB2 phase above the oxidation temperature at 1300 ο C that is to say, the ZrB2 phase of the ceramic suface is entirely oxidized. The oxidation layer thickness is increased with an increase in the oxidation time, however, the ratio of increasing thickness is less and less. The oxidation layer shows a loose structure during the initial stage of the oxidation, which lacks a barriers for the diffusion of the oxygen.
Effect of the sintering technology on the properties of fired brick from quartz sands
Jie-Guang Song,Fang Wang,Xiao-Bo Bai,Da-Ming Du,Yin-Yan Ju,Ming-Han Xu,Gang-Chang Ji 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.4
River sands as low grade natural raw materials are used to prepare the fired brick to replace clay fired bricks, which aims to save land resources and use low grade natural resources to realize high cost performance. In this paper, the effect of sintering technology of bricks on their performance is discussed. The compressive strength of fired bricks is first increased and then decreased with an increase in the sintering temperature, the compressive strength of bricks prepared by the isostatic compaction shaping is higher than that of bricks prepared by the plastic shaping under the same conditions. The compressive strength of bricks reaches 28 MPa when sintered at 1150 oC by using a 20MPa isostatic compaction shaping method. The compressive strength of bricks is first increased and then decreased by prolonging the holding time, the compressive strength of bricks reaches 28.9MPa when sintered at 1150 oC for 2 h.
Preparation and properties of ZrB2-YAG-Al2O3 ceramics
Jie-Guang Song,Gang-Chang Ji,Shi-Bin Li,Yang-Liang Li,Da-Ming Du,Lian-Meng Zhang,Yin-Yan Ju 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.4
ZrB2, YAG and Al2O3 are widely applied because of some excellent properties, but ZrB2 is easily oxidized in high-temperature air. To achieve better properties in ZrB2 ceramics, high-density ZrB2-YAG-Al2O3 ceramics were prepared. Below 1000℃, the shrinkage of ZrB2-YAG-Al2O3 ceramics is less than that of ZrB2-YAG ceramics. From 1000℃ to 1600℃, the second largest shrinkage occurs. Above 1600℃, the shrinkage of ZrB2-YAG-Al2O3 ceramics is more than that of ZrB2-YAG ceramics. The fracture toughness of sintered ceramics from coated raw materials is higher than that of sintered ceramics with mixed raw materials with the same phases and phase content, the fracture toughness of ZrB2-YAG-Al2O3 ceramics is higher than that of ZrB2-YAG ceramics with the same raw materials. The weight gain of all types of ceramics is increased with all increase in the oxidation temperature, the weight gain of ceramics is reduced with all increase in the YAG-Al2O3 content and Al2O3 proportion, especially above 1500℃. ZrB2, YAG and Al2O3 are widely applied because of some excellent properties, but ZrB2 is easily oxidized in high-temperature air. To achieve better properties in ZrB2 ceramics, high-density ZrB2-YAG-Al2O3 ceramics were prepared. Below 1000℃, the shrinkage of ZrB2-YAG-Al2O3 ceramics is less than that of ZrB2-YAG ceramics. From 1000℃ to 1600℃, the second largest shrinkage occurs. Above 1600℃, the shrinkage of ZrB2-YAG-Al2O3 ceramics is more than that of ZrB2-YAG ceramics. The fracture toughness of sintered ceramics from coated raw materials is higher than that of sintered ceramics with mixed raw materials with the same phases and phase content, the fracture toughness of ZrB2-YAG-Al2O3 ceramics is higher than that of ZrB2-YAG ceramics with the same raw materials. The weight gain of all types of ceramics is increased with all increase in the oxidation temperature, the weight gain of ceramics is reduced with all increase in the YAG-Al2O3 content and Al2O3 proportion, especially above 1500℃.
Development of a position sensitive CsI(Tl) crystal array
Shi, Guo-Zhu,Chen, Ruo-Fu,Chen, Kun,Shen, Ai-Hua,Zhang, Xiu-Ling,Chen, Jin-Da,Du, Cheng-Ming,Hu, Zheng-Guo,Fan, Guang-Wei Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.4
A position-sensitive CsI(Tl) crystal array coupled with the multi-anode position sensitive photomultiplier tube (PS-PMT), Hamamatsu H8500C, has been developed at the Institute of Modern Physics. An effective, fast, and economical readout circuit based on discretized positioning circuit (DPC) bridge was designed for the 64-channel multi-anode flat panel PSPMT. The horizontal and vertical position resolutions are 0.58 mm and 0.63 mm respectively for the 1.0 × 1.0 × 5.0 ㎣ CsI(Tl) array, and the horizontal and vertical position resolutions are 0.86 mm and 0.80 mm respectively for the 2.0 × 2.0 × 10.0 ㎣ CsI(Tl) array. These results show that the CsI(Tl) crystal array with low cost could be applied in the fields of medical imaging and high-resolution gamma camera.