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元素质在高校素质教育中的缺位——由高校“铁人班”引发的思考 被引量:1
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作者 熊兵 王龙 《武汉理工大学学报(社会科学版)》 2007年第5期704-706,共3页
元素质是实现目标素质所应具备的核心素质,铁人班的实质是传统教育方式在素质教育中的再现,是一种培养元素质的教育理念。元素质的培养要注重学生的细节教育和闲暇教育。
关键词 素质教育 元素质 目标素质 闲暇教育 细节教育
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语文学习素质:语文核心素养之“元”——王光龙语文学习素质培育观的启示
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作者 许建中 《语文教学通讯(初中)(B)》 2018年第4期13-16,共4页
学习素质是学生素质的“元素质”,语文学习素质是语文核心素养的“元素养”。语文教育工作者应高度重视培育学生的语文学习素质。培育学生的语文学习素质,尤须注意引导学生明确语文学习目标,遵循语文学习规律,优化语文学习方法,养成良... 学习素质是学生素质的“元素质”,语文学习素质是语文核心素养的“元素养”。语文教育工作者应高度重视培育学生的语文学习素质。培育学生的语文学习素质,尤须注意引导学生明确语文学习目标,遵循语文学习规律,优化语文学习方法,养成良好的语文学习习惯,并积极探索语文学习方法指导课的模式。 展开更多
关键词 语文学习素质 语文核心素养 元素质 培育策略 王光龙
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对我国大学生体育素质三元结构集成因子分析 被引量:3
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作者 李洪波 《山东体育学院学报》 北大核心 2008年第3期88-90,共3页
运用人类素质学的原理和方法,在简析我国大学生体育素质三元结构关系的基础上,重点对我国大学生体育素质结构元、素质演化元、教育内化元分别进行研讨,以求为高校体育素质教育提供参考。
关键词 体育素质 素质结构 素质演化 教育内化 循环 大学生
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粤港澳大湾区高技能人才培养的现实诉求与推进策略
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作者 谢德新 刘娟娟 汤婷婷 《广东技术师范大学学报》 2023年第4期83-91,共9页
粤港澳大湾区因其禀赋优良和区情独特,跨境要素集聚、产业体系完整、战略性新兴产业发展迅速,对高技能人才的需求尤为迫切。基于大湾区参与全球治理与国际竞争、引领经济开放新格局、培育世界级产业集群的现实需要,从元素质、专业素质... 粤港澳大湾区因其禀赋优良和区情独特,跨境要素集聚、产业体系完整、战略性新兴产业发展迅速,对高技能人才的需求尤为迫切。基于大湾区参与全球治理与国际竞争、引领经济开放新格局、培育世界级产业集群的现实需要,从元素质、专业素质、通用素质三个维度,阐明根源性素质、与工作情境相关的技能素质、贯穿于工作发展全程的通用素质的大湾区高技能人才素质特征。可通过加强大湾区顶层设计、建设职业院校战略联盟、构建职业教育校企命运共同体、整合职业教育资源、营造良好的社会氛围等,在培养制度、培养渠道、培养模式、培养内容、培养环境方面为大湾区高技能人才培养提供支撑,助推其在打造世界级产业集群和建设国际一流湾区上发挥应有作用。 展开更多
关键词 粤港澳大湾区 高技能人才 元素质 专业素质 通用素质
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Non-iterative image feature matching algorithm based on reference point correspondences 被引量:1
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作者 张维中 张丽艳 +2 位作者 王小平 丁志安 周玲 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期190-195,共6页
Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded ta... Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded target is put forward and the non-coded and coded targets are classified. Moreover, the gray scale centroid algorithm is applied to obtain the subpixel location of both uncoded and coded targets. The initial matching of the uncoded target correspondences between an image pair is established according to similarity and compatibility, which are based on the ID correspondences of the coded targets. The outliers in the initial matching of the uncoded target are eliminated according to three rules to finally obtain the uncoded target correspondences. Practical examples show that the algorithm is rapid, robust and is of high precision and matching ratio. 展开更多
关键词 reference points detection coded and non-coded target SUBPIXEL gray scale centroid point correspondence
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我国大学生体育素质三元结构的探析 被引量:6
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作者 马先英 《北京体育大学学报》 CSSCI 北大核心 2006年第8期1102-1104,共3页
运用《人类素质学》的基本原理,从经济学的视角,首先对我国大学生体育素质三元结构构件因子进行了解析,其次着重阐述了大学生体育素质三元循环互动发展的关系,最后得出大学生体育素质三元循环运动发展的规律,为高校体育素质教育提供参考。
关键词 体育素质 素质结构 素质外化 教育内化 循环 大学生
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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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Effects of Ca^(2+)concentrations on accumulations of mineral elements in the components of Pteroceltis tatarinowii 被引量:6
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作者 方升佐 候常英 洑香香 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期46-50,共5页
The bark of Pteroce/tis tatarinowii is a raw material for manufacturing XuanPaper. The effects of Ca^(2+) concentrations on the accumulation of mineral elements in the bark,leaf and root of Pteroceltis tatarinowii wer... The bark of Pteroce/tis tatarinowii is a raw material for manufacturing XuanPaper. The effects of Ca^(2+) concentrations on the accumulation of mineral elements in the bark,leaf and root of Pteroceltis tatarinowii were studied under controlled conditions. The types ofHoagland nutrient solution with three Ca^(2+) concentrations levels (200, 400 and 600 μg·g^(-1))and a control (without Ca^(2+)) were designed to culture Pteroceltis tatarinowii. After 6 months,contents of seven mineral elements including Ca, K, Mg, Mn, Zn, Cu and Na in the root, leaf and barkwere analyzed. The results indicated that Ca accumulations content in the root, leaf and bark hadpositively relation with Ca^(2+) concentrations (200, 400, 600 μg · g^(-1)), and the order of theCa content in the three components was root>leaf>bark. Ca content in the root treated with 600 μg·g^(-1) Ca^(2+) concentrations was 5.5 times as high as that of the control, and about 1.4 times ashigh as that of the root treated in 200 and 400 μg/g Ca^(2+) concentrations respectively. On thecontrary, K and Mg contents in the root, leaf and bark were negatively related to Ca^(2+)concentrations, especially in the bark, and their accumulation trend followed the order ofleaf>root>bark. K content in the bark treated with 600 μg ·g^(-1) Ca^(2+) concentrations was 39.3%of that of the control, and was 79.0% and 91.8% of that of the bark treated with 200 μg ·g^(-1)and 400 μg ·g^(-1) Ca^(2+) concentrations respectively; Mg content in the bark treated with 600μg ·g^(-1) Ca^(2+) concentrations was 23.4% of that of the control, and was 27.1% and 35.4% ofthat of the bark treated with 200 and 400 μg·g^(-1) Ca^(2+) concentrations respectively. Comparedwith the control, the general tendency of Mn, Zn and Cu content decreased with increasing of Ca^(2+)concentrations and their contents were in the order: root>leaf>bark. Based on the results of thisstudy, the experiment has been useful for providing academic bases in improving the bark quality ofPteroceltis tatarinowii on non-limestone soil. 展开更多
关键词 pteroceltis tatarinowii hoagland nutrient solution Ca^(2+) concentrations mineral element COMPONENT
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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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RELATIONSHIPS OF STARCH CONCENTRATION WITH SPECIFIC LEAF WEIGHT AND MINERAL CONCENTRATIONS IN POTATO LEAVES UNDER VARIED CO_2 AND TEMPERATURE 被引量:2
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作者 曹卫星 Theodore W.Tibbitts 《Acta Botanica Sinica》 CSCD 1997年第12期1118-1125,共8页
Foliar concentrations of starch and major nutrients N, P, K, Ca, and Mg along with specific leaf weight (SLW) were determined in the potato (Solanun tuberosum L.) cvs "Denali", "Norland "'and &... Foliar concentrations of starch and major nutrients N, P, K, Ca, and Mg along with specific leaf weight (SLW) were determined in the potato (Solanun tuberosum L.) cvs "Denali", "Norland "'and "Russet Burbank" grown for 35 days under the CO2 concentrations of 500, 1 000, 1 500 and 2 000 mol mol-1 at both 16 and 20℃ air temperature. The starch concentration, pooled from the three cultivars, increased with increasing CO2 concentration at both 16 and 20℃,, and was consistently higher at 16℃ than at 20℃. The SLW (g m-2) was positively related to the foliar starch concentration on the basis of leaf area or dry weight. The concentrations of N, P, Ca, and Mg in leaves were negatively related to starch concentration under 14% starch on a dry weight basis. Above 14%, there was no significant relationship between nutrient and starch concentrations . The similar patterns were seen when the SLW and nutrient concentrations were expressed on a starch-free basis. In contrast, the leaf concentration of K was not closely related to the starch concentration. The results indicated that the changes in SLW and concentrations of N, P, Ca, and Mg in potato leaves only partially resulted from the changed starch concentration. 展开更多
关键词 CO_2 concentration Temperature Specific leaf weight Starch concentration Mineral concentration POTATOES
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Correlation Analysis between Quality Characteristics and Fruit Mineral Element Contents in 'Fuji' Apples
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作者 张强 李兴亮 +3 位作者 李民吉 周贝贝 张军科 魏钦平 《Agricultural Science & Technology》 CAS 2017年第2期212-218,共7页
[Objective] The aims were to explore the relationship between the contents of fruit mineral elements and quality features of the 'Fuji' apple, screen major mineral elements of the fruit affecting fruit quality featu... [Objective] The aims were to explore the relationship between the contents of fruit mineral elements and quality features of the 'Fuji' apple, screen major mineral elements of the fruit affecting fruit quality features, and set up optimum proposals of fruit mineral elements for good fruit qualities, so as to provide a theoretical basis for the reasonable orchard soil and foliar fertilizer applications to increase fruit quality and reduce the physiological diseases related to the 'Fuji' apple. [Methods] The fruit mineral elements and quality indicators of 'Fuji" apples were in- vestigated and analyzed, which were collected from the 153 commercial apple or- chards of "Fuji' apple located in 51 counties. The variable importance for projection (VlP) of partial least squares regression (PLS) method was used to analyze the model effect and weight analysis impact of the fruit mineral element contents to fruit quality, screen out major factors of fruit mineral elements influencing the different fruit qualities, and set up the regression equation of the fruit qualities and major fruit mineral elements. Linear programming was used to obtain optimum proposals of the fruit mineral elements to achieve good 'Fuji' apple qualities. [Results] The mineral elements content and quality characteristics in "Fuji' apple fruit had great differences in the different produce regions in which the maximum content of nitro- gen, iron, zinc and boron in the 'Fuji' fruit were12.06, 6.17, 7.7, and 10.08 times greater than the minimum respectively, and the differences for titratable acid and the SSC/TA ratio were 2.33 and 2.16 times respectively. The correlation analysis between the fruit mineral element contents and qualities showed that the nitrogen content of fruit had a significantly negative correlation with the soluble solid content, SSC/TA ratio and red color area, while the calcium and iron contents in the fruit were in significantly positive correlation with the soluble solid content and SSC/TA ratio. The model effect and weight analysis showed that the content of nitrogen and iron in the fruit had a greater influence on the integral fruit quality, followed by phosphorus, potassium and calcium. The variable importance for projection (VlP) technology of PLS found that the mean fruit weight was primarily affected by nitro- gen, phosphorus and potassium, and the soluble solid was primarily affected by ni- trogen, calcium and iron, while the red color area was primarily affected by nitro- gen, potassium, calcium, iron and zinc. The regression equation between fruit quality and mineral element contents showed that the mean fruit weight had a greater pos- itive effect coefficient with the content of phosphorus and potassium, and a greater negative effect coefficient with the content of nitrogen in the fruit. Moreover, the sol- uble solid had the largest negative effect coefficient with nitrogen and largest posi- tive effect coefficient with calcium and iron in the fruit. [Conclusion] The maximum content of soluble solid and titratable acid were 1.5 times more than the minimum, and nitrogen, iron, zinc and boron were 6 times more than in the 'Fuji' apple fruit in the different produce regions. Therefore, it is a key technological measure to improve the overall qualities of the "Fuji' apple by decreasing the content of nitrogen, and increasing the contents of iron, phosphorus, potassium and calcium in the fruit. 展开更多
关键词 "Fuji' apple Fruit mineral element Fruit quality Partial least squares regression (PLS) Optimum proposals
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跨世纪医科大学生的基本素质和素质元培养目标 被引量:1
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作者 刘军保 《医学教育》 1998年第3期5-8,共4页
跨世纪医科大学生的基本素质和素质元培养目标海南医学院刘军保一般认为,素质是指人在先天生理的基础上,受后天环境教育的影响,通过个体自身的认识和社会实践养成的比较稳定的身心基本品质。但对素质的分类却仁者见仁,智者见智。有... 跨世纪医科大学生的基本素质和素质元培养目标海南医学院刘军保一般认为,素质是指人在先天生理的基础上,受后天环境教育的影响,通过个体自身的认识和社会实践养成的比较稳定的身心基本品质。但对素质的分类却仁者见仁,智者见智。有“六分法”、“五分法”、“四分法”... 展开更多
关键词 医学生 基本素质 素质 培养目标
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如何优化音乐课堂设计——中小学音乐教学法探秘 被引量:1
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作者 邓永业 《南方论刊》 2009年第10期103-104,共2页
本文在遵循教育部颁发的《音乐课程标准》的基础上,站在另一个高度,从教学结构、教学容量、学生课业负担这三方面入手,阐述了如何发掘优化课堂设计的新元素。
关键词 自主 合作 探究 素质
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Gas Exchange, Xylem Ions and Abscisic Acid Response to Na^+-Salts and Cl^--Salts in Populus euphratica 被引量:8
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作者 陈少良 李金克 +3 位作者 王天华 王沙生 Andrea POLLE Aloys HüTTERMANN 《Acta Botanica Sinica》 CSCD 2003年第5期561-566,共6页
We investigated the osmotic stress and ion-specific effects on xylem abscisic acid (ABA), ion uptake and transport and gas exchange in one-year-old seedlings of Populus euphratica Oliv. Net photosynthetic rates (P-n) ... We investigated the osmotic stress and ion-specific effects on xylem abscisic acid (ABA), ion uptake and transport and gas exchange in one-year-old seedlings of Populus euphratica Oliv. Net photosynthetic rates (P-n) and unit transpiration rates (TRN) were both significantly decreased upon an osmotic shock caused by PEG 6000 solution (osmotic potential = -0.24 MPa) or a saline, which was applied by 50 mmol/L Na+-salts (NaNO3 : NaHCO3 : NaH2PO4 = 5 : 4 : 1, pH 6.8, osmotic potential = -0.24 MPa) or by 50 mmol/L Cl--salts (KCl : NH4Cl = 1:1, osmotic potential = -0.24 MPa). However, salt-treated P. euphratica plants maintained typically higher TRN than those exposed to PEG. Xylem ABA concentrations increased rapidly following the PEG treatment, exhibiting peaking values at 1 h, then returning to pre-stress levels, followed by a gradual increase. Similarly, both Na+-treated and Cl--treated trees exhibited a rapid rise of ABA after salt stress was initiated. Notably, salt-treated plants maintained a relatively higher ABA than PEG-treated plants in a longer term. Collectively, results suggest that osmotic stress and ion-specific effects were both responsible for salt-induced ABA in P. euphratica : the initial rapid increase of xylem ABA appears to be a consequence of an osmotic shock, whereas specific salt effects seem to be responsible for ABA accumulation later on. Compared with Cl--treated trees, a higher inhibitory effect on gas exchange (P-n and TRN) was observed in Na+-salt plants, resulting from its long-sustained ABA and higher salt concentrations in the xylem. Displacement of membrane-associated Ca2+ by Na+ and the lesser capacity in Na+ compartmentation in root vacuoles likely contribute to the high influx of Na+ and Cl- in Na+-treated plants. Xylem K+, Ca2+ and Mg2+ concentrations were elevated by external Na+ -salts and Cl--salts, suggesting that P. euphratica maintained a higher capacity in nutrient uptake under saline conditions, which makes a contribution to its salinity tolerance. 展开更多
关键词 xylem ABA MACRONUTRIENTS TRANSPIRATION photosynthesis Na+-salts Cl--salts PEG Populus euphratica
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Effects of Reducing Mn^(2+),Cu^(2+) and Zn^(2+) Concentrations in Nutrient Solution on SOD Activity in Grafted Cucumber Seedling Leaves Under Cold Stress
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作者 李涛 高俊杰 于贤昌 《Agricultural Science & Technology》 CAS 2011年第11期1625-1627,1679,共4页
[Objective] The research aimed to study the effects of reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution on the contents of Mn, Cu and Zn of grafted cucumber leaves as well as on the SOD and is... [Objective] The research aimed to study the effects of reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution on the contents of Mn, Cu and Zn of grafted cucumber leaves as well as on the SOD and isozymes activities and the rate of electrolytic leakage under cold stress. [Method] Nutrient solution containing low concentrations of Mn2+, Cu2+ or Zn2+ were used for cultivating the grafted cucumber seedlings for the cold treatment. [Result] The results indicated that reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution had declined the SOD activities in grafted cucumber leaves and increased the rates of electrolytic leakage. Mn2+ had shown the maximum influences, followed by Cu2+, and Zn2+ had shown the minimum influences. [Conclusion] Cold resistance of cucumber can be improved by changing the contents of Mn2+, Cu2+ or Zn2+ in nutrient solution. 展开更多
关键词 Grafted cucumber Microelement Cold stress SOD Rate of electrolytic leakage
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Effects of Ca2+concentrations on accumulations of mineral elements in the components of Pteroceltis tatarinowii 被引量:4
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作者 方升佐 候常英 洑香香 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期46-50,94,共页
The bark of Pteroceltis tatarinowii is a raw material for manufacturing Xuan Paper. The effects of Ca2+ concentrations on the accumulation of mineral elements in the bark, leaf and root of Pteroceltis tatarinowii were... The bark of Pteroceltis tatarinowii is a raw material for manufacturing Xuan Paper. The effects of Ca2+ concentrations on the accumulation of mineral elements in the bark, leaf and root of Pteroceltis tatarinowii were studied under controlled condi-tions. The types of Hoagland nutrient solution with three Ca2+ concentrations levels (200, 400 and 600 靏g-1) and a control (without Ca2+) were designed to culture Pteroceltis tatarinowii. After 6 months, contents of seven mineral elements including Ca, K, Mg, Mn, Zn, Cu and Na in the root, leaf and bark were analyzed. The results indicated that Ca accumulations content in the root, leaf and bark had positively relation with Ca2+ concentrations (200, 400, 600 靏g-1), and the order of the Ca content in the three components was root】leaf】bark. Ca content in the root treated with 600 靏g-1 Ca2+ concentrations was 5.5 times as high as that of the control, and about 1.4 times as high as that of the root treated in 200 and 400 靏/g Ca2+ concentrations respectively. On the contrary, K and Mg contents in the root, leaf and bark were negatively related to Ca2+ concentrations, especially in the bark, and their accumulation trend followed the order of leaf】root】bark. K content in the bark treated with 600 靏g-1 Ca2+ con-centrations was 39.3% of that of the control, and was 79.0% and 91.8% of that of the bark treated with 200 靏g-1 and 400靏g-1 Ca2+ concentrations respectively; Mg content in the bark treated with 600 靏g-1 Ca2+ concentrations was 23.4% of that of the control, and was 27.1% and 35.4% of that of the bark treated with 200 and 400 靏g-1 Ca2+ concentrations respectively. Com-pared with the control, the general tendency of Mn, Zn and Cu content decreased with increasing of Ca2+ concentrations and their contents were in the order: root】leaf】bark. Based on the results of this study, the experiment has been useful for providing academic bases in improving the bark quality of Pteroceltis tatarinowii on non-limestone soil. 展开更多
关键词 Pteroceltis tatarinowii Hoagland nutrient solution Ca2+ concentrations Mineral element COMPONENT
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Recent developments in the use of single-atom catalysts for water splitting 被引量:10
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作者 Yao Wang Xun Huang Zidong Wei 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第8期1269-1286,共18页
Electrochemical water splitting is regarded as the most promising approach to produce hydrogen.However,the sluggish electrochemical reactions occurring at the anode and cathode,namely,the oxygen evolution reaction(OER... Electrochemical water splitting is regarded as the most promising approach to produce hydrogen.However,the sluggish electrochemical reactions occurring at the anode and cathode,namely,the oxygen evolution reaction(OER)and the hydrogen evolution reaction(HER),respectively,consume a tremendous amount of energy,seriously hampering its wide application.Recently,single-atom catalysts(SACs)have been proposed to effectively enhance the kinetics of these two reactions.In this minireview,we focus on the recent progress in SACs for OER and HER applications.Three classes of SACs have been reviewed,i.e.,alloy-based SACs,carbon-based SACs and SACs supported on other compounds.Different factors affecting the activities of SACs are also highlighted,including the inherent element property,the coordination environment,the geometric structure and the loading amount of metal atoms.Finally,we summarize the current problems and directions for future development in SACs. 展开更多
关键词 Single-atom catalyst Electrochemical water splitting Inherent element property Coordination environment Geometric structure
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Concentration, Distribution, and Occurrence of REEs in Coals from Chongqing,Southwest China 被引量:5
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作者 LI Da-hua TANG Yue-gang +3 位作者 CHEN Kun DENG Tao CHENG Fang-ping LIU Dong 《Journal of China University of Mining and Technology》 EI 2005年第3期227-233,共7页
The concentration, distribution, and occurrence of rare earth elements (REEs) in coals as well as stone coalsin different geological periods from Chongqing were studied. The results show that the REE content in coals ... The concentration, distribution, and occurrence of rare earth elements (REEs) in coals as well as stone coalsin different geological periods from Chongqing were studied. The results show that the REE content in coals fromChongqing is much higher than that of the ordinary Chinese coals, the Late Paleozoic coals from North China, UScoals, and the world coals. Although the concentration of light rare earth elements (LREE) is higher than that of heavyrare earth elements (HREE), the ratio of LREE to HREE is as low as 5.11. The REE content decreases with thecoal-formation periods from old to new. The REE content in the Sinian stone coal is the highest, but it is the lowest inEarly Jurassic coals. The similar REE contents in bituminous coals and anthracite show that the metamorphism has alittle influence on REE content in coal. In addition, silicate association dominates the occurrence mode of REEs incoals from Chongqing. 展开更多
关键词 coal rare earth elements CONCENTRATION CHONGQING
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Elemental Composition and Geochemical Characteristics of Iron-Manganese Nodules in Main Soils of China 被引量:11
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作者 TAN Wen-Feng LIU Fan +2 位作者 LI Yong-Hua HU Hong-Qing HUANG Qiao-Yun 《Pedosphere》 SCIE CAS CSCD 2006年第1期72-81,共10页
Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and funct... Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and functions of iron-manganese nodules in soils and sediment. Compared to the corresponding soils, Mn, Ba, Cd, Co and Pb had strong accumulation, Ni had moderate accumulation, while Ca, Cu, Fe, Na, P, Sr and Zn accumulated to a minor degree in the iron-manganese nodules. In contrast, Si, Al, K, Mg and Ti were reduced in the iron-manganese nodules. The contents of Ba, Cd, Co, Cu, Ni, Pb and Zn were positively and significantly correlated with that of MnO2 in the iron-manganese nodules, while the contents of Cr, Cu, Ni, Pb and Zn were positively and significantly correlated with that of Fe2O3 in soils. Based on a principle component analysis, the elements of iron-manganese nodules were divided into four groups: 1) Mn, Ba, Cd, Co, Cu, Li, Ni, Pb and Zn that were associated with Mn oxides, 2) Fe, Cr and P that were associated with Fe oxides, 3) Si, K, and Mg that were included in the elemental composition of phyllosilicate, and 4) Ca, Na, Al and Ti that existed in todorokite, birnessite, lithiophorite and phyllosilicate. It was suggested that accumulation, mineralization and specific adsorption were involved in the formation processes of soil iron-manganese nodules. 展开更多
关键词 elemental composition geochemical characteristics iron-manganese nodule soil
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Correlation Analysis between Cracking and Mineral Element Content of Apricot Fruit 被引量:2
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作者 Guowei NIE Kai LI +6 位作者 Yongqiang TIAN Guilin DAI Xiaohua YANG Yonghong SONG Jingjiang Li Xiaoping ZHANG Jingli LYU 《Agricultural Science & Technology》 CAS 2017年第10期1852-1855,1859,共5页
This study aimed to clarify the effectsof mineral nutrient contents on fruit cracking so as to provide certain reference for further study on fruit cracking in apricot and basis for reasonable fertilization in the pro... This study aimed to clarify the effectsof mineral nutrient contents on fruit cracking so as to provide certain reference for further study on fruit cracking in apricot and basis for reasonable fertilization in the production. The 39-year-old apricot trees, with plant and row spacing of 3.0 m×4.0 m, were selected as the test materials, and the effects of contents of 7 kinds of mineral elements on the fruit cracking in apricot were analyzed. The results of variance analysis showed the intensity of correlation between mineral element content and apricot fruit cracking ranked as Ca's 〉 Zn's 〉 Mn's 〉 Fe's 〉 K's 〉 Mg's 〉 Cu's, The content of Ca was negatively correlated with cracking index, and the correlation ,coefficient was larger; the correlations between the contents of Zn and Mn and cracking index were weaker; and the correlations between the contents of Fe, K, Mg and Cu and cracking index were extremely weak. In conclusion, Ca deficiency is the main factor affecting fruit cracking in apricot. 展开更多
关键词 APRICOT Mineral element CRACKING Correlation analysis
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