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对基于音乐“四元素”的幼儿音乐启蒙教育的思考 被引量:1
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作者 杨静 《新课程研究》 2022年第35期99-101,共3页
声音的色彩、声音的强弱、声音的高低、声音的长短这音乐“四元素”是音乐的基石,是幼儿认知音乐与感受音乐的重要基础。因此,在幼儿音乐启蒙教育中,培养幼儿对音乐“四元素”的基本认知与感受能力,是重要且必要的。文章立足于音乐“四... 声音的色彩、声音的强弱、声音的高低、声音的长短这音乐“四元素”是音乐的基石,是幼儿认知音乐与感受音乐的重要基础。因此,在幼儿音乐启蒙教育中,培养幼儿对音乐“四元素”的基本认知与感受能力,是重要且必要的。文章立足于音乐“四元素”在幼儿音乐启蒙教育中的重要意义,对如何基于音乐“四元素”实施幼儿音乐启蒙教育进行理论与实践方面的论述。 展开更多
关键词 幼儿音乐 启蒙教育 音乐“四元素”
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监控“四元素”,减轻运算量
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作者 阮伟强 《中学数学研究》 2003年第4期25-27,共3页
关键词 “四元素” 运算量 解析几何 数学 教学 高中
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新疆阿尔泰可可托海3号伟晶岩脉磷灰石矿物中稀土元素“四分组效应”及其意义 被引量:19
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作者 张辉 刘丛强 《地球化学》 CAS CSCD 北大核心 2001年第4期323-334,共12页
新疆阿尔泰可可托海3号伟晶岩脉磷灰石矿物中稀土元素REE和其他微量元素的ICPMS分析结果表明,Y/Ho、Zr/Hf和Nb/Ta明显偏离球粒陨石中对应的比值,并存在显著的REE“四分组效应”。REE“四分组效应”量化特征参数TE34主要与Y/Ho、... 新疆阿尔泰可可托海3号伟晶岩脉磷灰石矿物中稀土元素REE和其他微量元素的ICPMS分析结果表明,Y/Ho、Zr/Hf和Nb/Ta明显偏离球粒陨石中对应的比值,并存在显著的REE“四分组效应”。REE“四分组效应”量化特征参数TE34主要与Y/Ho、Nb/Ta分异程度有关,与δEu负异常演化程度相一致。锰铝榴石也呈现REE“四分组效应”和Y/Ho、Nb/Ta显著分异,指示REE“四分组效应”是形成伟晶岩熔体的一个基本特征,并不是由富LREE矿物(如独居石)和富HREE矿物(如石榴子石)结晶引起的残余熔体REE含量的异常变化,其机制可能是富F、B和P的过铝质熔体与含水流体间相互作用。REE在流体相/熔体相的分配受温度、压力和流体相组成复合控制的综合结果。 展开更多
关键词 伟晶岩 磷灰石 元素分异 新疆维吾尔自治区 稀土元素“四分组效应” 形成机制 存在方式 岩浆演化
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过铝质岩浆体系中不相容元素的地球化学行为及机理——元素对分异和稀土元素“四重效应”及其对流体作用过程的指示意义 被引量:7
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作者 刘丛强 张辉 《高校地质学报》 CAS CSCD 2003年第4期648-660,共13页
根据对新疆阿尔泰3号伟晶岩脉各结构带中磷灰石的微量元素组成的系统研究,并综合了目前世界上对不同演化程度的酸性岩浆岩(I型和S型花岗岩、过铝质花岗岩、花岗伟晶岩)的研究成果,对通常具有相似离子半径和相同离子电价的元素对比值变... 根据对新疆阿尔泰3号伟晶岩脉各结构带中磷灰石的微量元素组成的系统研究,并综合了目前世界上对不同演化程度的酸性岩浆岩(I型和S型花岗岩、过铝质花岗岩、花岗伟晶岩)的研究成果,对通常具有相似离子半径和相同离子电价的元素对比值变化以及稀土元素“四重效应”产生的原因进行了分析。研究认为,这些元素对的分异和稀土元素“四重效应”的产生与富含挥发分流体相的存在密切相关,流体/熔体相作用的程度可能是制约元素对分异和稀土元素“四重效应”大小的主要因素。 展开更多
关键词 过铝质岩浆体系 不相容元素分异 稀土元素“四重效应”
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Analysis of Mineral Elements in 13 Famous Tea Varieties in Sichuan Province 被引量:7
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作者 李春华 王云 《Agricultural Science & Technology》 CAS 2009年第2期130-133,共4页
This study was to analyze the mineral elements in famous tea varieties in Sichuan Province. Eighteen mineral elements in the samples of 13 famous tea varieties in Sichuan Province were measured via related instruments... This study was to analyze the mineral elements in famous tea varieties in Sichuan Province. Eighteen mineral elements in the samples of 13 famous tea varieties in Sichuan Province were measured via related instruments. The results showed, of all the 18 measured samples, that the contents of K, P, S, Ca and Mg were relatively higher( 〉1 500 mg/kg) in famous tea varieties in Sichuan Province, while those of Ba, Cr, V, Co and Se were relatively lower( 〈 10 mg/kg) ; compared to common green tea, the famous tea varieties in Sichuan Province contained higher contents of K, Zn, P, Na, Ni, Cu, S, Se and Co(0.38% -115.65% higher than that in common green tea), and lower contents of Mg, Mn, AI, Ca, V, Rb, Fe and Cr(7.20% -46.67% lower than that in common green tea); of the 13 tested tea varieties, Hongyanyingchun, Yongchuanxiuya and Qingchengxueya were rich in mineral elements, while Yuchengyunwu and Yuqiancha lacked in mineral elements. The re- suits show that Hongyanyingchun, Yongchuanxiuya and Qingchengxueya are the elites in the famous tea varieties in Sichuan Province. 展开更多
关键词 Famous tea variety Mineral element Sichuan Province
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Mineral Elements in Different Varieties of Camellia sinensis 被引量:15
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作者 李春华 王云 《Agricultural Science & Technology》 CAS 2009年第1期105-107,共3页
To understand the mineral elements in different varieties of tea ( Camellia sinensis), 17 mineral elements in eight tea varieties including Yunnan Dayezhong, No. 43 Longjing and No. 6 Zaobaijian, were measured. The ... To understand the mineral elements in different varieties of tea ( Camellia sinensis), 17 mineral elements in eight tea varieties including Yunnan Dayezhong, No. 43 Longjing and No. 6 Zaobaijian, were measured. The results showed that nine elements, such as P, K, Ba, Mn, Cu, were significantly different among varieties, others did not. Black tea varieties usually contain high contents of Cu and K. As a conclusion, mineral elements should be extensively considered in breeding tea varieties. 展开更多
关键词 Camellia sinensis BREEDING Mineral element
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Origin of Quaternary Red Clay of Southern Anhui Province 被引量:9
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作者 HUXUEFENG YUANGUODONG 《Pedosphere》 SCIE CAS CSCD 1998年第3期267-272,共6页
The particle size distribution, heavy mineral constituents and rare earth elements (REE) characteristics of the Quaternary red clay of southern Anhui Province were studied to explore the origin of the clay. The resul... The particle size distribution, heavy mineral constituents and rare earth elements (REE) characteristics of the Quaternary red clay of southern Anhui Province were studied to explore the origin of the clay. The results showed that the clay had some properties of areolian deposits, which could be compared with those of the loess in North China; and its chondrite normalized curves of REE were similar to those of the Xiashu loess, implying that they shared the same origin. It was concluded in combination with the results reported by other researchers that the Quaternary red clay of southern Anhui Province originated from aeolian deposits, and this could reveal the cycles of warm and cold climates in the area during the Quaternary period. 展开更多
关键词 heavy mineral constituents particle size distribution Quaternary red clay rare earth elements characteristics
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Sm/TiCl_4 (cat.) system-mediated intermolecular and intramolecular reductive coupling reactions of ketones with esters 被引量:1
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作者 LIU Yun-kui XU Dan-qian +1 位作者 XU Zhen-yuan ZHANG Yong-min 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期999-1003,共5页
Sm/TiCl4 system could well integrate the high reactivity of samarium(Ⅱ) and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupl... Sm/TiCl4 system could well integrate the high reactivity of samarium(Ⅱ) and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupling reactions of ketones with esters mediated by metallic samarium (Sm) and a catalytic amount of titanium tetrachloride (TiCl4) were successfully developed. A series of substituted ketones and cyclic β-keto-esters were prepared in moderate to good yields under reflux and neutral conditions. 展开更多
关键词 Samarium (Sm) Titanium tetrachloride (TiCl4) Ketone Ester Reductive coupling reaction
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Protective effect of selenium-enriched lactobacilluson CCI_4-induced liver injury in mice and its possible mechanisms 被引量:20
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作者 Long Chen Dao-Dong Pan +1 位作者 Juan Zhou Ying-Zi Jiang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5795-5800,共6页
AIM: To study the protective effects and mechanisms of Se-enriched lactobacillus on liver injury caused by carbon tetrachloride (CCl4) in mice. METHODS: Seventy-two ICR mice were randomly divided into four groups... AIM: To study the protective effects and mechanisms of Se-enriched lactobacillus on liver injury caused by carbon tetrachloride (CCl4) in mice. METHODS: Seventy-two ICR mice were randomly divided into four groups: normal group, CCl4-induced model group, low Se-enriched lactobacillus treatment group (L-Se group), and high Se-enriched lactobacillus treatment group (H-Se group). During a 3-wk experimental period, the common complete diet was orally provided daily for normal group and model group, and the mice in L-Se and H-Se groups were given a diet with 2 and 4 mg of organoselenium from Se-enriched lactobacillus per kg feed, respectively. From the 2nd wk of experiment, the model group, L-Se group, and H-Se group received abdominal cavity injection of olive oil solution containing 500 mL/L CCl4 (0.07 mL/100 g body mass) to induce liver injury, and the normal group was given olive oil on every other day for over 2 wk. In the first 2 wk post injection with CCl4, mice in each group were killed. The specimens of blood, liver tissue, and macrophages in abdominal cavity fluid were taken. Then the activities of the following liver tissue injury-associated enzymes including glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as well as malondialdehyde (MDA) content were assayed. Changes of phagocytic rate and phagocytic index in macrophages were observed with Wright-Giemsa stain. Plasma TNF-α level was measured by radioimmunoassay. The level of intracellular free Ca^2+ ([Ca^2+]i) in hepatocytes was detected under a laser scanning confocal microscope. RESULTS: During the entire experimental period, the AST and ALT activities in liver were greatly enhanced by CCl4 and completely blunted by both low and high doses of Se-enriched lactobacillus. The Se-enriched lactobacillus- protected liver homogenate GSH-Px and SOD activities were higher or significantly higher than those in model group and were close to those in normal group. CCl4 significantly increased MDA content in liver homogenates, while administration of Se-enriched lactobacillus prevented MDA elevation. Phagocytic rate and phagocytic index of macrophages decreased after CCl4 treatment compared to those in normal control, but they were dramatically rescued by Se-enriched lactobacillus, showing a greatly higher phagocytic function compared to model group. CCl4 could significantly elevate plasma TNF-α and hepatocyte [Ca^2+]i level, which were also obviously prevented by Se-enriched lactobacillus. CONCLUSION: Se-enriched lactobacillus can intervene in CCl4-induced liver injury in mice by enhancing macrophage function activity to keep normal and beneficial effects, elevating antioxidant-enzyme activities and reducing lipid peroxidation reaction, inhibiting excessive release of TNF-α, preventing the dramatic elevation of [Ca^2+]i in hepatocytes. 展开更多
关键词 Se-enriched lactobacillus Liver injury Carbon tetrachloride Macrophage Ca^2+
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The Energy-orthogonal Tetrahedral Finite Element for Fourth Order Elliptic Equations 被引量:1
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作者 LIU Ming-fang CAO Ji-wei CHEN Shao-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期388-393,共6页
In this paper,the 16-parameter nonconforming tetrahedral element which has an energy-orthogonal shape function space is presented for the discretization of fourth order elliptic partial differential operators in three... In this paper,the 16-parameter nonconforming tetrahedral element which has an energy-orthogonal shape function space is presented for the discretization of fourth order elliptic partial differential operators in three spatial dimensions.The newly constructed element is proved to be convergent for a model biharmonic equation. 展开更多
关键词 nonconforming finite element tree-dimension fourth order elliptic equation
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Molecular Structure of Organolanthanide Complex [(η~5-CH_3C_5H_4)_2Tb(μ-Cl)(THF)]_2
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作者 WU Zhong-Zhi HUANG Zu-En +2 位作者 CAI Rui-Fang(Department of Chemistry, Fudan University Shanghai 200433)ZHOU Xi-Geng XU Zheng YOU Xiao-Zeng(State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093)HUANG Xiao-Ying(State Key Laboratory 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1996年第5期367-370,共4页
The complex [(η5-CH3C5H4)2Tb(μ-Cl) (THF)]2, has been studied by X-ray crystallography. The crystal is orthorhombic , space group Phcn with a= 20.414(2),b=9. 548(1),c=16.390(6)A.V=3194.9(6) A3, Mr=849.46,Z=4,Dc=1.77 ... The complex [(η5-CH3C5H4)2Tb(μ-Cl) (THF)]2, has been studied by X-ray crystallography. The crystal is orthorhombic , space group Phcn with a= 20.414(2),b=9. 548(1),c=16.390(6)A.V=3194.9(6) A3, Mr=849.46,Z=4,Dc=1.77 g/cm3, F(000)=1664,μ=46.37 cm-1.The Tb3+ ion is coordinated by two CH3C5H4 groups, two chloride ions and one oxygen atom from tetrahydrofuran to form a distorted trigonal bipyramidal geometry. Two bridging Tb-Cl bond lengths are 2. 716(2) and 2.790(2)A,respectively.The Tb-O (THF) and average Tb-C(CH3C5H4) bond lengths are 2.559(6) and 2.670(4)A,respectively. 展开更多
关键词 LANTHANIDE TERBIUM methylcyclopentadienyl crystal structure
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