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51.
52.
Effect of TiO<Subscript>2</Subscript> on the viscosity and structure of low-fluoride slag used for electroslag remelting of Ti-containing steels 下载免费PDF全文
The viscosity of CaF2-CaO-Al2O3-MgO-(TiO2) slag was measured using a rotating crucible viscometer. Raman spectroscopy analysis was performed to correlate the viscosity to slag structure. The viscosity of the slag was found to decrease with increasing TiO2 content in the slag from 0 to 9.73wt%. The activation energy decreased from 95.16 kJ/mol to 79.40 kJ/mol with increasing TiO2 content in the slag. The introduction of TiO2 into the slag played a destructive role in Al-O-Al structural units and Q4 units by forming simpler structural units of Q2 and Ti2O64- chain. The amount of Al-O-Al significantly decreased with increasing TiO2 content. The relative fraction of Q4 units in the[AlO4]5--tetrahedral units shows a decreasing trend, whereas the relative fraction of Q2 units and Ti2O64- chain increases with increasing TiO2 content accordingly. Consequently, the polymerization degree of the slag decreases with increasing TiO2 content. The variation in slag structure is consistent with the change in measured viscosity. 相似文献
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54.
Genetic variation near IRS1 associates with reduced adiposity and an impaired metabolic profile 总被引:1,自引:0,他引:1
Kilpeläinen TO Zillikens MC Stančákova A Finucane FM Ried JS Langenberg C Zhang W Beckmann JS Luan J Vandenput L Styrkarsdottir U Zhou Y Smith AV Zhao JH Amin N Vedantam S Shin SY Haritunians T Fu M Feitosa MF Kumari M Halldorsson BV Tikkanen E Mangino M Hayward C Song C Arnold AM Aulchenko YS Oostra BA Campbell H Cupples LA Davis KE Döring A Eiriksdottir G Estrada K Fernández-Real JM Garcia M Gieger C Glazer NL Guiducci C Hofman A Humphries SE Isomaa B Jacobs LC Jula A Karasik D Karlsson MK 《Nature genetics》2011,43(8):753-760
Genome-wide association studies have identified 32 loci influencing body mass index, but this measure does not distinguish lean from fat mass. To identify adiposity loci, we meta-analyzed associations between ~2.5 million SNPs and body fat percentage from 36,626 individuals and followed up the 14 most significant (P < 10(-6)) independent loci in 39,576 individuals. We confirmed a previously established adiposity locus in FTO (P = 3 × 10(-26)) and identified two new loci associated with body fat percentage, one near IRS1 (P = 4 × 10(-11)) and one near SPRY2 (P = 3 × 10(-8)). Both loci contain genes with potential links to adipocyte physiology. Notably, the body-fat-decreasing allele near IRS1 is associated with decreased IRS1 expression and with an impaired metabolic profile, including an increased visceral to subcutaneous fat ratio, insulin resistance, dyslipidemia, risk of diabetes and coronary artery disease and decreased adiponectin levels. Our findings provide new insights into adiposity and insulin resistance. 相似文献
55.
Cho YS Chen CH Hu C Long J Ong RT Sim X Takeuchi F Wu Y Go MJ Yamauchi T Chang YC Kwak SH Ma RC Yamamoto K Adair LS Aung T Cai Q Chang LC Chen YT Gao Y Hu FB Kim HL Kim S Kim YJ Lee JJ Lee NR Li Y Liu JJ Lu W Nakamura J Nakashima E Ng DP Tay WT Tsai FJ Wong TY Yokota M Zheng W Zhang R Wang C So WY Ohnaka K Ikegami H Hara K Cho YM Cho NH Chang TJ Bao Y Hedman ÅK Morris AP McCarthy MI;DIAGRAM Consortium;MuTHER Consortium Takayanagi R Park KS Jia W Chuang LM Chan JC Maeda S Kadowaki T Lee JY Wu JY 《Nature genetics》2012,44(1):67-72
We conducted a three-stage genetic study to identify susceptibility loci for type 2 diabetes (T2D) in east Asian populations. We followed our stage 1 meta-analysis of eight T2D genome-wide association studies (6,952 cases with T2D and 11,865 controls) with a stage 2 in silico replication analysis (5,843 cases and 4,574 controls) and a stage 3 de novo replication analysis (12,284 cases and 13,172 controls). The combined analysis identified eight new T2D loci reaching genome-wide significance, which mapped in or near GLIS3, PEPD, FITM2-R3HDML-HNF4A, KCNK16, MAEA, GCC1-PAX4, PSMD6 and ZFAND3. GLIS3, which is involved in pancreatic beta cell development and insulin gene expression, is known for its association with fasting glucose levels. The evidence of an association with T2D for PEPD and HNF4A has been shown in previous studies. KCNK16 may regulate glucose-dependent insulin secretion in the pancreas. These findings, derived from an east Asian population, provide new perspectives on the etiology of T2D. 相似文献
56.
Effect of TiO2 on the viscosity and structure of low-fluoride slag used for electroslag remelting of Ti-containing steels 下载免费PDF全文
The viscosity of CaF2–CaO–Al2O3–MgO–(TiO2) slag was measured using a rotating crucible viscometer. Raman spectroscopy analysis was performed to correlate the viscosity to slag structure. The viscosity of the slag was found to decrease with increasing TiO2 con-tent in the slag from 0 to 9.73wt%. The activation energy decreased from 95.16 kJ/mol to 79.40 kJ/mol with increasing TiO2 content in the slag. The introduction of TiO2 into the slag played a destructive role in Al–O–Al structural units and Q4 units by forming simpler structural units of Q2 and426TiO- chain. The amount of Al–O–Al significantly decreased with increasing TiO2 content. The relative fraction of4Q units in the [AlO4]5?-tetrahedral units shows a decreasing trend, whereas the relative fraction of2Q units and426TiO- chain increases with increasing TiO2 content accordingly. Consequently, the polymerization degree of the slag decreases with increasing TiO2 content. The varia-tion in slag structure is consistent with the change in measured viscosity. 相似文献
57.
Forecasts for leverage heterogeneous autoregressive models with jumps and other covariates 下载免费PDF全文
For leverage heterogeneous autoregressive (LHAR) models with jumps and other covariates, called LHARX models, multistep forecasts are derived. Some optimal properties of forecasts in terms of conditional volatilities are discussed, which tells us to model conditional volatility for return but not for the LHARX regression error and other covariates. Forecast standard errors are constructed for which we need to model conditional volatilities both for return and for LHAR regression error and other blue covariates. The proposed methods are well illustrated by forecast analysis for the realized volatilities of the US stock price indexes: the S&P 500, the NASDAQ, the DJIA, and the RUSSELL indexes. 相似文献
58.
Hyerim Han Sang Hyeon Koh Bo Young Han Yeong Jin Chung Sang Chul Shin 《南京林业大学学报(自然科学版)》2010,34(4):175-175
以往研究认为,2006年前在韩国唯一的传播松材线虫的天牛是松褐天牛,但是最近的研究发现云杉花墨天牛也能传播松材线虫。对于两种天牛携带和传播线虫种类,特别是对拟松材线虫的携带和传播途径需要进一步研究。拟松材线虫分为欧洲型和东亚型,在韩国两种生物型都存在。笔者的研究表明大部分云杉花墨天牛携带的是欧洲型的拟松材线虫。 相似文献
59.
Kittichai Chaiseeda Shin A. Moteki D. Sahadeva Reddy Di Wu Kusumlata Chandra James M. Takacs 《复旦学报(自然科学版)》2005,44(5):631-632
We recently described a new combinatorial strategy for modular catalyst development, one using self-as-embly in the ligand scaffold-generating step to produce libraries of chiral self-assembled ligands. Metal-directed self-assembly of bifunetional subunits around a structural metal (typically zinc) can be used to form a heteroleptic complex in which a second set of ligating groups are suitably disposed to form a heterobimetallie cata- lyst system. See Fig. 1 相似文献
60.
Se-Yong Song Sang-Wook Yeh Soon-Il An Jong-Seong Kug Seung-Ki Min Seok-Woo Son Jongsoo Shin 《科学通报(英文版)》2022,(2):213-222
Understanding the regional hydrological response to varying CO2 concentration is critical for cost-benefit analysis of mitigation and adaptation polices in the ... 相似文献