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离散求和法应用于空气弹簧ANSYS多步分析 被引量:1
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作者 李锋祥 丁玉梅 杨卫民 《北京化工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第1期58-61,66,共5页
列举了空气弹簧ANSYS仿真过程中存在的一些问题和难点。介绍了EQ6111空气弹簧的结构和材料特点,并针对性地建立了空气弹簧的有限元模型。针对空气弹簧分析过程中所存在的气压载荷问题,采取了多步分析的思路。在此思路的基础之上,采用离... 列举了空气弹簧ANSYS仿真过程中存在的一些问题和难点。介绍了EQ6111空气弹簧的结构和材料特点,并针对性地建立了空气弹簧的有限元模型。针对空气弹簧分析过程中所存在的气压载荷问题,采取了多步分析的思路。在此思路的基础之上,采用离散求和法编写胶囊容积计算宏,应用于空气弹簧的垂向和横向静态力学性能分析,并将分析结果与试验结果和前人分析结果进行了比较,取得了较高的模拟分析精度,并且大大提高了仿真过程的连续性和可控制性。 展开更多
关键词 空气弹簧 ANSYS 气压载荷 多步分析 离散求和法
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胶囊容积计算宏应用于空气弹簧ANSYS多步分析
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作者 李锋祥 杨卫民 丁玉梅 《橡塑技术与装备》 CAS 2007年第1期5-10,共6页
列举了空气弹簧ANSYS仿真过程中存在的一些问题和难点,针对空气弹簧分析过程中所存在的气压载荷问题,采取了多步分析的思路。在此思路的基础之上,提出了体积叠加法、离散求和法和拉格朗日插值函数法3种胶囊容积计算方法,并对每一种方法... 列举了空气弹簧ANSYS仿真过程中存在的一些问题和难点,针对空气弹簧分析过程中所存在的气压载荷问题,采取了多步分析的思路。在此思路的基础之上,提出了体积叠加法、离散求和法和拉格朗日插值函数法3种胶囊容积计算方法,并对每一种方法作了详细介绍。3种胶囊容积计算方法的提出,对于解决空气弹簧多步分析过程中的气压载荷问题有直接帮助,为胶囊容积计算宏的编写提供了思路和算法基础。最后将基于体积叠加法和离散求和法的胶囊容积计算宏应用于空气弹簧的垂向静态分析,得到了满意的结果。 展开更多
关键词 空气弹簧 ANSYS 气压载荷 多步分析 胶囊容积计算宏
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非线性微分方程的多步修正和修正的渐近Adomian分解法(英文)
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作者 陈芳 刘青泉 《应用数学与计算数学学报》 2017年第2期224-240,共17页
Adomian分解方法是解微分方程的一种分析方法.基于Adomian分解方法和修正的渐近Adomian分解方法,给出了多步修正的渐近Adomian分解方法.指出修正的渐近Adomian分解方法可以给出非线性微分方程的精确解.多步修正的渐近Adomian分解方法也... Adomian分解方法是解微分方程的一种分析方法.基于Adomian分解方法和修正的渐近Adomian分解方法,给出了多步修正的渐近Adomian分解方法.指出修正的渐近Adomian分解方法可以给出非线性微分方程的精确解.多步修正的渐近Adomian分解方法也可以给出精确解且最小化计算量.一些数值例子表明多步修正的渐近Adomian分解方法的有效性.对于一些问题,多步修正的渐近Adomian分解方法是优于Adomian分解方法和修正的渐近Adomian分解方法. 展开更多
关键词 Adomian分解 修正的渐近Adomian分解 非线性微分方程 多步分析方法
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基于隐结构分析建立中医证候分型规则的三种方法 被引量:37
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作者 许玉龙 吴秀艳 +3 位作者 李延龙 王天芳 张连文 薛晓琳 《世界科学技术-中医药现代化》 CSCD 北大核心 2019年第1期101-108,共8页
中医治疗疾病时,首先需要把患者进行辨证分型,疾病的辨证分型标准主要是专家组通过讨论确定的,具有较强的主观性。本文介绍三种基于无标签数据建立辨证分型规则的方法:隐类分析、单步隐树分析和双步隐树分析,并基于801例肝炎肝硬化患者... 中医治疗疾病时,首先需要把患者进行辨证分型,疾病的辨证分型标准主要是专家组通过讨论确定的,具有较强的主观性。本文介绍三种基于无标签数据建立辨证分型规则的方法:隐类分析、单步隐树分析和双步隐树分析,并基于801例肝炎肝硬化患者中医症状数据,对三种方法进行对照比较,明确它们各自的优势和不足,以便在临床研究中选择使用。这些方法的使用可以促进辨证分型的客观化,提高临床诊疗的一致性。 展开更多
关键词 隐类分析 隐树分析 多步隐树分析 BIC评分
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单晶体应力测量的X射线衍射分析 被引量:4
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作者 黄斌 杨延清 +1 位作者 曾冬梅 艾艳玲 《科学技术与工程》 2006年第18期2991-2993,共3页
采用HiroshiSuzuki等人提出的多步回归分析方法,结合不对称布拉格衍射,对CdZnTe单晶片的残余应力进行了测量。与传统的单晶体应力测量方法比较,这种新方法可以准确测定平面应力状态下的单晶体应力而不受d0值不可靠所带来的影响。
关键词 单晶体 应力 X射线 多步回归分析 不对称布拉格衍射
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APDL实现空气弹簧动态试验仿真 被引量:3
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作者 李锋祥 杨卫民 丁玉梅 《特种橡胶制品》 2007年第4期50-54,70,共6页
介绍了EQ6111空气弹簧的试验方法和结构材料特点,并针对性地在ANSYS中建立了空气弹簧的三维有限元模型。针对空气弹簧分析过程中所存在的气压载荷问题,采取多步分析的思路,基于离散求和法APDL编写胶囊容积计算宏,应用于空气弹簧的垂向... 介绍了EQ6111空气弹簧的试验方法和结构材料特点,并针对性地在ANSYS中建立了空气弹簧的三维有限元模型。针对空气弹簧分析过程中所存在的气压载荷问题,采取多步分析的思路,基于离散求和法APDL编写胶囊容积计算宏,应用于空气弹簧的垂向和横向动态力学性能分析,得出了位移载荷频率分别为0.5Hz,1Hz,2Hz和2.5Hz下的横向和垂向动态力学性能分析结果。研究表明,载荷频率是影响空气弹簧动态力学性能的关键外在因素之一。本文的研究为更进一步的空气弹簧动态力学性能的有限元分析奠定了基础。 展开更多
关键词 空气弹簧 ANSYS 多步分析 APDL 动态力学性能 载荷频率
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深基坑开挖支护体系理论及其应用评述 被引量:13
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作者 林天健 《力学与实践》 CSCD 北大核心 1996年第2期1-9,共9页
本文对深基坑开挖支护的一些新的技术和作法及其应用从理论上进行某些分析并作综合评述.其中特别注意介绍一些近似计算方法并简要援引工程实例.
关键词 深基坑 变形控制 支护体系 多步分析 开挖
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Correlation and path analysis of morphological and weight traits in marine gastropod Glossaulax reiniana 被引量:11
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作者 赵力强 何阳阳 +2 位作者 杨凤 聂鸿涛 闫喜武 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期821-827,共7页
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wil... Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs. 展开更多
关键词 Glossaulax reiniana correlation and path analysis morphological traits weight traits
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Association of glomerular filtration rate with arterial stiffness in Chinese women with normal to mildly impaired renal function 被引量:4
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作者 Su-Yan Bian Hong-Yang Guo +6 位作者 Ping Ye Lei-Ming Luo Hong-Mei Wu Wen-Kai Xiao Li-PingQi He-Peng Yu Liu-Fa Duan 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2012年第2期158-165,共8页
Objective Both decreased glomemlar filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness... Objective Both decreased glomemlar filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness and the degree of GFR loss. Whether decreased GFR contributes to peripheral artery stiffness remains controversial. Moreover, data analyzed from a cohort of Chinese women are rare. Our aim was to explore the relationship between GFR and regional arterial stiffness in Chinese women. Methods In this cross-sectional study, we randomly recruited 1131 adult women residents with GFR 〉 60 mL/min per 1.73 m2 estimated by the Chinese Modification of Diet in Renal Disease equation from three large communities. Central and peripheral arterial stiffness were estimated simultaneously by measuring carotid-femoral pulse wave velocity (PWVcf) and carotid-radial PWV (PWVcr) using a validated automatic device. Augmentation Index at heart rate 75 beats/minutes (AIx-75) was measured by pulse wave analysis as a composite parameter reflecting both large and distal arterial properties. Results The mean estimated GFR (eGFR) of the study group was 100.05 + 23.26 mL/minute per 1.73 m2. Subjects were grouped by tertiles of eGFR level. PWVef and AIx-75 increased ongoing from the top to the bottom eGFR tertile, while the values of PWVcr were comparable. Both univariate Pearson correlations and multiple stepwise regression analyses showed that eGFR significantly correlated to PWVcf, but not to PWVcr and AJx-75. Conclusions In Chinese women with normal to mildly impaired renal function, decreased eGFR affected carotid-to-femoral rather than carotid-to-radial stiffening. This provides rational to conduct future prospective studies to investigate predictors of atherosclerosis in this population. 展开更多
关键词 Arterial stiffness Augmentation index Pulse wave velocity Glomerular filtration rate Chinese women
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A rabbit model of pediatric nonalcoholic steatohepatitis: The role of adiponectin 被引量:10
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作者 Jun-Fen Fu Yan-Lan Fang Li Liang Chun-Lin Wang Fang Hong Guan-Ping Dong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第8期912-918,共7页
AIM: To create a rabbit model of pediatric nonalcoholic steatohepatitis (NASH) and to evaluate the role of adiponectin in the process. METHODS: Thirty-two specific pathogen-free male New Zealand rabbits were divid... AIM: To create a rabbit model of pediatric nonalcoholic steatohepatitis (NASH) and to evaluate the role of adiponectin in the process. METHODS: Thirty-two specific pathogen-free male New Zealand rabbits were divided randomly into three groups: (1) the normal control group (n = 10) was fed with standard diet for 12 wk; (2) the model group A (n = 11); and (3) model group B (n = 11) were fed with a highfat diet (standard diet + 10% lard + 2% cholesterol) for 8 and 12 wk, respectively. Hepatic histological changes were observed and biochemical parameters as well as serum levels of adiponectin, interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α were measured. RESULTS: Typical histological hepatic lesions of NASH were observed in both model groups described as liver steatosis, liver inflammatory infiltration, cytologic ballooning, perisinusoidal fibrosis and overall fibrosis. Compared with the normal control group, there were significant increases in model groups A and B in weight gain (1097.2 ± 72.3, 1360.5± 107.6 vs 928.0 ±58.1, P 〈 0.05, P 〈 0.01), liver weight (93.81±6.64, 104.6±4.42 vs 54.4±1.71, P 〈 0.01), Lg (ALT) (1.9±0.29, 1.84± 0.28 vs 1.60±0.17, P 〈 0.01), and Lg (TG) (1.03 ±0.24, 1.16 ±0.33 vs 0.00 ±0.16, P 〈 0.01). Weight gain was much more in model group B than in model group A (1360.5± 107.6 vs 1097.2 ±72.3, P 〈 0.05). But, there was no significant difference between the two groups concerning the other indexes. Pro-inflammatory cytokines (IL-6 and TNF-α) increased in model group B compared with that of control and model group A (IL-6:1.86±0.21 vs 1.41 ±0.33, 1.38± 0.42, P 〈 0.01; TNF-α: 1.18±0.07 vs 0.66 ±0.08, 0.86 ±0.43, P 〈 0.01, P 〈 0.05), whereas serum adiponectin and IL-10 decreased in model groups compared with that in the control (adiponectin: A: 21.87±4.84 and B: 21.48 ±4.60 vs 27.36 ±7.29, P 〈 0.05. IL-10: A: 1.72± 0.38 and B: 1.83 ±0.39 vs 2.26±0.24, P 〈 0.01). Lg (TC) and the degree of liver fatty infiltration was an independent determinant of serum adiponectin level analyzed by stepwise multiple regressions, resulting in 29.4% of variances. CONCLUSION: This rabbit model produces the key features of pediatric NASH and may provide a realistic model for future studies. Adiponectin level partially reflects the severity of liver steatosis, but not the degree of liver inflammation. 展开更多
关键词 Nonalcoholic steatohepatitis Pediatricanimal model ADIPONECTIN Interleukin 6 Tumornecrosis factor
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Exergy Analysis of Single and Multi-Step Thermal Processes 被引量:1
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作者 Gudni Albert Johannesson Marco Molinari 《Journal of Civil Engineering and Architecture》 2012年第10期1384-1391,共8页
The present paper introduces the concepts of exergy and treats it applications to analysis of the gain in exergy efficiency between one-step and multi-step thermal processes. The analysis, which is carried out with th... The present paper introduces the concepts of exergy and treats it applications to analysis of the gain in exergy efficiency between one-step and multi-step thermal processes. The analysis, which is carried out with the Excel-based SEPE program, is exemplified with the comparison between single-step and two-steps heat pump setup for providing heat to a floor heating system and for domestic hot water. The paper discusses the use of the concept of exergy efficiency as a measure of success for design of a heat pump application and how the use of information on exergy destruction and temperature levels in different parts of the system add a new perspective to the analysis and the evaluation of the system performance. The paper shows how this information can be used to improve the system configuration and also the operation of the system for given boundary conditions. This is especially useful when the energy from the low temperature sources can be utilized at different temperature or quality levels such as for space heating and domestic hot water. 展开更多
关键词 EXERGY energy management buildings systems performance.
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Tolerance, Oxygen Consumption and Ammonia Excretion of Ophiopholis sarsii vadicola in Different Temperatures and Salinities
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作者 FANG Jinghui ZHANG Jihong +5 位作者 JIANG Zengjie ZHAO Xuewei JIANG Xu DU Meirong GAO Yaping FANG Jianguang 《Journal of Ocean University of China》 SCIE CAS 2015年第3期549-556,共8页
There are more than 2000 species of brittle stars in the world. For most of them, many scientific questions including basic characteristics of eco-physiology are still unknown. In the present study, Ophiopholis sarsii... There are more than 2000 species of brittle stars in the world. For most of them, many scientific questions including basic characteristics of eco-physiology are still unknown. In the present study, Ophiopholis sarsii vadicola acclimated at 15 ℃, salinity 31, were assessed for temperature monia excretion were studied at different temperatures (5, 10, and salinity tolerance. Its oxygen consumption and am- 15, 20, 25℃) and salinities (25, 30, 35). O. sarsii vadi- cola could tolerate 0-24℃ and no brittle star was dead in the salinity range of 19-48 in the experimental situation. Two-way ANOVA showed that the oxygen consumption and ammonia excretion normalized with both dry mass and wet mass, Q10, which is used to describe the temperature sensitivity of respiration, and moisture content were significantly affected by temperature and salinity, and the combined effects of the two factors were significant. Stepwise multiple regression analysis revealed that logarithmic oxygen consumption and ammonia excretion showed a significant positive relationship with logarithmic temperature and salinity. The logarithmic moisture content of the brittle stars showed an inverse relationship with logarithmic salinity, but a positive relationship with logarithmic temperature. This suggests that the tolerance of temperature and salinity of brittle stars is closely related to their living environment, and that the effects of temperature on oxygen consumption are more significant at higher salinity, and that the ammonia excretion is less affected by salinity at lower temperatures. 展开更多
关键词 Ophiopholis sarsii vadicola TOLERANCE oxygen consumption ammonia excretion TEMPERATURE SALINITY
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Research into the Assessment of the Intercultural Sensitivity Among University Students of Science and Technology
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作者 Mei-Lan Huang 《Sino-US English Teaching》 2013年第2期110-116,共7页
Globalization makes people from diverse cultural backgrounds communicate effectively. To be a global citizen has become the goal of our education. Landis and Bhagat (1996) argued that intercultural sensitivity is cr... Globalization makes people from diverse cultural backgrounds communicate effectively. To be a global citizen has become the goal of our education. Landis and Bhagat (1996) argued that intercultural sensitivity is crucial to enable people to live and work with others from different cultural backgrounds. With higher intercultural sensitivity, one will be more global as his understanding of cultural difference becomes more sophisticated. In this present study, the intercultural sensitivity of different majors from a private institute of technology in the north of Taiwan was investigated, using the ISS (Intercultural Sensitivity Scale) developed by Chen and Starosta (2000). Based on a survey of 358 participants from Nursing Department and Department of Nutrition and Health Sciences, this study focused on five dimensions of the intercultural sensitivity and the participants' demographic factors affecting their performance on intercultural sensitivity. The five dimensions included in this study were: (1) interaction engagement, (2) interaction confidence, (3) respect for cultural differences, (4) interaction enjoyment, and (5) interaction attentiveness. Among the five dimensions of intercultural sensitivity, the participants had the highest score on the dimension of "respect for the cultural differences" and had the lowest score on the dimension of "interaction confidence". Results generated by stepwise multiple regression indicated "decision of studying abroad" and "experiences of living abroad" could effectively predict the participants' intercultural sensitivity. 展开更多
关键词 intercultural sensitivity ISS (Intercultural Sensitivity Scale) cultural differences university of scienceand technology
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Leaf stable carbon isotope composition in Picea schrenkiana var. tianschanica in relation to leaf physiological and morphological characteristics along an altitudinal gradient
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作者 ZHANG Hui-wen WU Zhen XIAO Hong-lang 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1217-1228,共12页
To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of P... To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 m to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that all the leaf traits differed significantly among sampling sites along the altitudinal gradient(P<0.001). LA, SD, LPC, LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla+b, LDMC, LMA and Narea varied non-linearly with changes in altitude. Stepwise multiple regression analyses showed that four controlled physiological and morphological characteristics influenced the variation of δ13C. Among these four controlled factors, LKC was the most profound physiological factor that affected δ13C values, LA was the secondary morphological factor, SD was the third morphological factor, LNC was the last physiological factor. This suggested that leaf δ13C was directly controlled by physiological and morphological adjustments with changing environmental conditions due to the elevation. 展开更多
关键词 Alpine trees Leaf Carbon isotope composition Physiological characteristics Morphological characteristics Altitudinal variation
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离子色谱法测定蚀刻槽废氢氟酸中的六氟硅酸 被引量:4
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作者 霍世欣 罗全迁 曹琳 《色谱》 CAS CSCD 北大核心 2016年第10期982-985,共4页
建立了一种新的检测蚀刻槽废氢氟酸中六氟硅酸的离子色谱方法.色谱柱为Metrosep A Supp 7 阴离子交 换柱,流动相为3. 2 mmol/L 碳酸钠-1. 0 mmol/L 碳酸氢钠,流速为0. 7 mL/min.六氟桂酸经过抑制型电导检测 器后进行衍生化反应,在360 n... 建立了一种新的检测蚀刻槽废氢氟酸中六氟硅酸的离子色谱方法.色谱柱为Metrosep A Supp 7 阴离子交 换柱,流动相为3. 2 mmol/L 碳酸钠-1. 0 mmol/L 碳酸氢钠,流速为0. 7 mL/min.六氟桂酸经过抑制型电导检测 器后进行衍生化反应,在360 nm波长下用紫外检测器检测.六氟硅酸的线性范围为2. 4- 120 mg/L ,相关系数r 2 大于0. 999,定量限为0. 24 mg/L ,平均加标回收率为97. 2%.本方法还可以同时利用电导检测器检测废氢氟酸中 的氢氟酸、醋酸、盐酸、硝酸、磷酸和硫酸的含量.该方法快速、准确,适用于蚀刻槽液中六氟硅酸的检测. 展开更多
关键词 离子色谱 紫外检测器 电导检测器 六氟硅酸
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Transient Analysis and Control Strategies for a Quad-lnverter Multiphase Multilevel Motor Drive in Faulty Conditions
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作者 Gabriele Grandi Padmanaban Sanjeevkumar Yasser Gritli 《Journal of Energy and Power Engineering》 2013年第7期1304-1315,共12页
In this paper, post-fault-tolerant control strategies for quad-inverter multiphase-multilevel induction motor drives are investigated. More specifically, four standard two-level three-phase VSIs (voltage source inver... In this paper, post-fault-tolerant control strategies for quad-inverter multiphase-multilevel induction motor drives are investigated. More specifically, four standard two-level three-phase VSIs (voltage source inverters) supplying the open-end windings of a dual three-phase induction motor is considered, quadrupling the power capability of a single VSI with given voltage and current ratings. In healthy conditions, the control algorithm is able to generate multi-level voltage waveforms, equivalent to the ones of a three-level inverter and to share the total motor power among the four dc sources in each switching period. This sharing capability is investigated under post-fault operating conditions, when one VSI must be completely insulated due to a severe failure on it. In this case, the conversion power unit can operate with a reduced power rating by a proper modulation of the remaining three VSIs. The whole ac motor drive has been numerically implemented, and the effectiveness of the proposed control strategies under healthy and post-fault operating conditions have been proved. 展开更多
关键词 Dual three-phase motor multi-level inverter multi-phase motor drive multi-phase fault post-fault-tolerance space vectormodulation.
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Association between moderately oxidized low-density lipoprotein and high-density lipoprotein particle subclass distribution in hemodialyzed and post-renal transplant patients 被引量:5
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作者 Elzbieta KIMAK Magdalena HALABI +2 位作者 Iwona BARANOWICZ-GASZCZYK Janusz SOLSKI Andrzej KSIAZEK 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第5期365-371,共7页
Disturbances in the metabolism of lipoprotein profiles and oxidative stress in hemodialyzed (HD) and post-renal transplant (Tx) patients are proatherogenic, but elevated concentrations of plasma high-density lipop... Disturbances in the metabolism of lipoprotein profiles and oxidative stress in hemodialyzed (HD) and post-renal transplant (Tx) patients are proatherogenic, but elevated concentrations of plasma high-density lipoprotein (HDL) reduce the risk of cardiovascular disease. We investigated the concentrations of lipid, lipoprotein, HDL particle, oxidized low-density lipoprotein (ox-LDL) and anti-ox-LDL, and paraoxonase-1 (PON-1) activity in HD (n=33) and Tx (n=71) patients who were non-smokers without active inflammatory disease, liver disease, diabetes, or malignancy. HD patients had moderate hypertriglyceridemia, normocholesterolemia, low HDL-C, apolipoprotein A-I (apoA-I) and HDL particle concentrations as well as PON-1 activity, and increased ox-LDL and anti-ox-LDL levels. Tx patients had hypertriglyceridemia, hypercholesterolemia, moderately decreased HDL-C and HDL particle concentrations and PON-1 activity, and moderately increased ox-LDL and anti-ox-LDL levels as compared to the reference, but ox-LDL and anti-ox-LDL levels and PON-1 activity were more disturbed in HD patients. However, in both patient groups, lipid and lipoprotein ratios (total cholesterol (TC)/HDL-C, LDL-C/HDL-C, triglyceride (TG)/HDL-C, HDL-C/non-HDL-C, apoA-I/apoB, HDL-C/apoA-I, TG/HDL) were atherogenic. The Spearman's rank coefficient test showed that the concentration of ox-LDL correlated positively with HDL particle level (R=0.363, P=0.004), and negatively with TC (R=-0.306, P=0.012), LDL-C (R=-0.283, P=0.020), and non-HDL-C (R=-0.263, P=0.030) levels in Tx patients. Multiple stepwise forward regression analysis in Tx patients demonstrated that ox-LDL concentration, as an independent variable, was associated significantly positively with HDL particle level. The results indicated that ox-LDL and de- creased PON-1 activity in Tx patients may give rise to more mildly-oxidized HDLs, which are less stable, easily undergo metabolic remodeling, generate a greater number of smaller pre-13-HDL particles, and thus accelerate reverse cholesterol transport, which may be beneficial for Tx patients. Further studies are necessary to confirm this. 展开更多
关键词 Lipids LIPOPROTEINS Paraoxonase-1 (PON-1) activity Oxidized low-density lipoprotein (ox-LDL) High-density lipoprotein (HDL) particles Post-renal transplant HEMODIALYSIS
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