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攀枝花地区昔格达组土壤中微量元素地球化学分异特征 被引量:6
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作者 滕彦国 倪师军 张成江 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第3期288-294,共7页
昔格达组在攀枝花地区分布广泛,并成为该区居民的主要集散地和工农业活动区。对昔格达组粘土中微量元素的空间分布及分异特征研究的结果表明(1)土壤的粒度、矿物组成及成土作用是影响土壤中微量元素浓度的重要条件;(2)人类工矿开发活动... 昔格达组在攀枝花地区分布广泛,并成为该区居民的主要集散地和工农业活动区。对昔格达组粘土中微量元素的空间分布及分异特征研究的结果表明(1)土壤的粒度、矿物组成及成土作用是影响土壤中微量元素浓度的重要条件;(2)人类工矿开发活动是制约土壤中微量元素区域分布形式的重要因素;(3)土壤在不同层位的分异及组合特征既与成土母质有关,也受人为活动的影响。 展开更多
关键词 微量元素 地球化学分异 昔格达组粘土 攀枝花地区
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中国白浆土研究——Ⅰ.白浆土机械组成特点及元素地球化学分异特征 被引量:11
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作者 律兆松 徐琪 《土壤学报》 CAS CSCD 北大核心 1993年第3期274-288,共15页
本文对采自我国白浆土主要分布区的四个典型剖面的机械组成,化学性质及元素地球化学分异特征进行了研究。结果表明,所研究的四个剖面从以>0.002mm的颗粒为基础计算的非粘粒粒径在剖面中的分布、土壤的硅铝率、铝钾镁率以及以非粘粒... 本文对采自我国白浆土主要分布区的四个典型剖面的机械组成,化学性质及元素地球化学分异特征进行了研究。结果表明,所研究的四个剖面从以>0.002mm的颗粒为基础计算的非粘粒粒径在剖面中的分布、土壤的硅铝率、铝钾镁率以及以非粘粒为基础计算的土体TiO_2含量来衡量,母质是同源的;在成土过程中,粘粒由白浆层向淀积层淋淀,形成了两层在机械组成上的“双层性”,而不是母质两次沉积的结果;元素地球化学分异特征是:SiO_2和MnO在白浆层中富集,Fe_2O_3在淀积层中富集,Al_2O_3的富集因成土条件不同而异;Fe_2O_3、MnO、Al_2O_3反TiO_2向粘粒中富集,SiO_2向粗颗粒中富集;白浆土中粘土矿物似有微弱的破坏作用。 展开更多
关键词 白浆土 机械组成 地球化学分异
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天山及其邻近地区土壤某些元素的地球化学分异初探 被引量:2
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作者 黄标 龚子同 顾国安 《土壤学报》 CAS CSCD 北大核心 1994年第2期180-189,共10页
本文在34个土壤剖面181个样品大量元素和36个剖面176个样品的Zn、Ni、Cn、Co、V等微量元素分析资料的基础上,讨论了天山及其邻近地区土壤成土的地球化学过程、这些元素的空间分异。认为天山及其邻近地区土壤的形成... 本文在34个土壤剖面181个样品大量元素和36个剖面176个样品的Zn、Ni、Cn、Co、V等微量元素分析资料的基础上,讨论了天山及其邻近地区土壤成土的地球化学过程、这些元素的空间分异。认为天山及其邻近地区土壤的形成存在着三个主要的成土地球化学过程,即脱盐基过程、镁、钙积过程、钠积过程;随海拔高度的降低,水分减少、温度升高,元素的空间分异表现为:盐基自高山淋溶后,朝着盆地方向,按它们的盐类溶解度大小.分别富集钙、镁、钠等的盐类;微量元素含量自高山至盆地逐渐减少。 展开更多
关键词 元素 土壤 地球化学分异 天山地区
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天然文岩渠地区土壤盐渍地球化学分异的遥感分析
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作者 赵俊琳 《地域研究与开发》 1988年第2期57-64,共8页
天然文岩渠流域位于黄淮海平原的西南部,历史上黄河在此多次改道决口泛滥,塑造了决口扇形地、古河道、各种洼地、黄河滩地和背河湿地。微地貌影响水流方向和速度及土壤质地。在水平方向上有沙土、壤土和粘土的差别;在同一土壤剖面上还... 天然文岩渠流域位于黄淮海平原的西南部,历史上黄河在此多次改道决口泛滥,塑造了决口扇形地、古河道、各种洼地、黄河滩地和背河湿地。微地貌影响水流方向和速度及土壤质地。在水平方向上有沙土、壤土和粘土的差别;在同一土壤剖面上还有沙、粘、壤等间层。该流域属于大陆性季风气候。年平均降水量在620mm左右,其中夏季占全年降水量的一半以上,年蒸发量在1900mm以上,为降水量的3倍,蒸发积盐大于淋溶脱盐。该区降水的明显不均,形成土壤在一年内有季节性积盐和季节性淋盐的两个相反的过程,导致该区的土壤发生表土积盐。我们可分别在淋溶脱盐期和蒸发积盐期进行航空遥感,在试验中。 展开更多
关键词 遥感 化学分异 天然 积盐 脱盐 航空遥感 地球 季节性 年降水量 微地貌
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应用构造地球化学进行成矿与找矿分析 被引量:2
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作者 陈先兵 池三川 《矿床地质》 CAS CSCD 北大核心 1994年第S1期52-54,共3页
应用构造地球化学进行成矿与找矿分析陈先兵,池三川(中国地质大学,北京100083)1构造、地球化学及矿床之间的关系地壳中记录的构造变形(宏、微观构造)和地球化学场(元素迁移聚集)特征正是地壳运动行为的基本表现形式。构... 应用构造地球化学进行成矿与找矿分析陈先兵,池三川(中国地质大学,北京100083)1构造、地球化学及矿床之间的关系地壳中记录的构造变形(宏、微观构造)和地球化学场(元素迁移聚集)特征正是地壳运动行为的基本表现形式。构造变形的时空演化遵循着变形强度和性... 展开更多
关键词 构造地球化学 构造变形 元素迁移 显微构造 陈先 断裂构造 压溶 化学分异 应力场 构造单元
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山东官里庄金矿成矿力致热分形弥散分异—富集机理 被引量:1
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作者 刘文化 秦德殿 +2 位作者 杨晋升 张殿龙 王风海 《黄金科学技术》 2011年第3期43-48,共6页
力致热分形弥散化学分异—富集机理是矿床学研究中的难点和热点,以山东官里庄矿化区为例,分别从矿化区地质特证,构造热效应对岩体、脉岩和矿体的控制及一些量值计算,对该区力致热与分形弥散成矿机理半定量—定量的变化关系进行较深入性... 力致热分形弥散化学分异—富集机理是矿床学研究中的难点和热点,以山东官里庄矿化区为例,分别从矿化区地质特证,构造热效应对岩体、脉岩和矿体的控制及一些量值计算,对该区力致热与分形弥散成矿机理半定量—定量的变化关系进行较深入性的研究。 展开更多
关键词 力致热 形弥散 化学分异—富集机理 官里庄金矿 山东省
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赤峰南部地区构造地球化学分带、矿产、构造的关系
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作者 盛民 刘金玉 《西部资源》 2005年第6期56-59,共4页
关键词 地球化学 构造活动 海西期花岗岩 地球化学分异 成矿元素 古生代 西拉木伦河 中生代 压缩性 成矿带
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青海西部尕斯库勒盐湖沉积物中铀和钍地球化学特征探讨 被引量:3
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作者 叶传永 王志明 +3 位作者 郝伟林 林效宾 韩军 郑绵平 《矿床地质》 CAS CSCD 北大核心 2014年第5期1081-1090,共10页
文章以柴达木盆地西部尕斯库勒盐湖沉积物为研究对象,通过对钻孔沉积物和地表沉积物中铀和钍含量的研究,探讨了盐湖沉积物中铀和钍的地球化学特征。分析表明,钻孔沉积物中铀和钍之间存在明显的正相关关系。在横向上,随地表取样点逐渐远... 文章以柴达木盆地西部尕斯库勒盐湖沉积物为研究对象,通过对钻孔沉积物和地表沉积物中铀和钍含量的研究,探讨了盐湖沉积物中铀和钍的地球化学特征。分析表明,钻孔沉积物中铀和钍之间存在明显的正相关关系。在横向上,随地表取样点逐渐远离湖表卤水,沉积物中铀和钍的含量先增高后又急剧降低,且受补给水铀含量影响大;在纵向上,同一个晶间卤水层或者碎屑物沉积层内铀含量垂直分异明显,铀含量随深度增加而递增。就沉积物中铀和钍的赋存形式而言,2/3的铀被黏土质点吸附,1/3的铀夹杂在盐类矿物中;而90%以上的钍被黏土质点吸附,10%以下的钍夹杂在盐类矿物中。干盐滩中毛细蒸发和淋滤等化学沉积分异作用造成盐湖沉积中心的沉积物铀含量相对较高。 展开更多
关键词 地球化学 沉积物 铀和钍 化学沉积作用 尕斯库勒盐湖
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冥古宙地球的冷却、分异和构造体制及其比较行星学研究 被引量:1
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作者 刘耘 章清文 《科学通报》 EI CAS CSCD 北大核心 2023年第18期2284-2295,共12页
冥古宙是地球历史的最初阶段,虽然仅持续不到6亿年,但在此期间发生巨大的物质运移和重新分布,地球的地核、地幔、地壳和大气层等主要圈层框架已基本形成,为地球后续漫长的物质和能量演变奠定了基础.由于关键地质记录缺失、研究手段匮乏... 冥古宙是地球历史的最初阶段,虽然仅持续不到6亿年,但在此期间发生巨大的物质运移和重新分布,地球的地核、地幔、地壳和大气层等主要圈层框架已基本形成,为地球后续漫长的物质和能量演变奠定了基础.由于关键地质记录缺失、研究手段匮乏等原因,当前地球科学界针对冥古宙地球演化的研究仍十分有限,使其成为地球科学最为薄弱的一环.鉴于冥古宙地球存在地质记录匮乏这一“痛点”,以及太阳系类地天体(泛指类地行星、矮行星、卫星和小行星等岩石质天体)在原始物质组成、内部结构、热演化和构造体制演变等方面的相似性,借助比较行星学手段,从太阳系内各类地天体(现今或早期)保存完好的地质记录研究类地天体演化的一般规律,以此弥补早期地球演化认识的空白.这是一种重要且可行的研究手段,也是突破现有地学理论框架(如板块构造理论)、开辟新的地学研究格局的重要契机.本文对早期地球的热演化、内部分异和构造体制等关键领域的研究进展及其存在的问题进行了梳理,同时探讨了未来可能的突破点. 展开更多
关键词 冥古宙地球 热演化 化学分异 构造体制 比较行星学
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察尔汗开发区资源环境的初步研究(下)
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作者 胡东生 《青海环境》 1992年第4期183-192,共10页
研究察尔汗盐湖首采区的晶间卤水组分的年度变化规律,即对青钾一期工程1988年采卤过程中水化学变化进行讨论,其中青钾一选厂小渠道抽卤的影响并入总体影响范围之内,不作单独阐述。根据晶间卤水组分年际变化态势,划分为平稳变化区、剧烈... 研究察尔汗盐湖首采区的晶间卤水组分的年度变化规律,即对青钾一期工程1988年采卤过程中水化学变化进行讨论,其中青钾一选厂小渠道抽卤的影响并入总体影响范围之内,不作单独阐述。根据晶间卤水组分年际变化态势,划分为平稳变化区、剧烈变化区以及调整变化区。以表征采卤后的晶间卤水组分变化趋势及采卤影响效应。 展开更多
关键词 察尔汗 变化 采卤 变化趋势 总体影响 高值区 化学分异 年际变化 干盐湖 转换点
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ISOFLAVONES FROM ASTRAGALUS MEMBRANACEUS 被引量:45
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作者 宋纯清 郑志仁 +2 位作者 刘涤 胡之璧 盛宛云 《Acta Botanica Sinica》 CSCD 1997年第8期764-768,共5页
Two new isoflavones (8, 3'-dihydroxy-7,4'-dimethoxyisoflavone, odoratin-7-0-[3-D-glu-copyranoside) and four known isoflavones (formononetin, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, calycosin, calycosi... Two new isoflavones (8, 3'-dihydroxy-7,4'-dimethoxyisoflavone, odoratin-7-0-[3-D-glu-copyranoside) and four known isoflavones (formononetin, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, calycosin, calycosin-7-0-(3-D-glucopyranoside) were isolated from the roots of Astragalus mem-branaceus (Fisch.) Bunge. Their structures were established by spectral analysis. 展开更多
关键词 Astragalus membranaceus ISOFLAVONES 8 3'-dihydroxy-7 4'-dimethoxyisoflavone odoratin-7-O-D-glucopyranoside
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大陆岩石圈地震界面性质
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作者 N.I.Pavlenkova 束沛镒 《地球物理学进展》 CSCD 1989年第4期41-52,共12页
科拉半岛的深钻揭示了三类地震界面:(1)分隔不同组分和年龄岩石的岩性界面;(2)归因于断层的构造界面;(3)由不同的孔隙率或裂隙区所控制的机械界面。地震研究表明前两类界面有非常复杂的结构,且是上地壳的特征;在10—15km深度以下,观测... 科拉半岛的深钻揭示了三类地震界面:(1)分隔不同组分和年龄岩石的岩性界面;(2)归因于断层的构造界面;(3)由不同的孔隙率或裂隙区所控制的机械界面。地震研究表明前两类界面有非常复杂的结构,且是上地壳的特征;在10—15km深度以下,观测到岩石圈中有一明显的近水平层构造。在古地台的地壳中部,由于扩容形成了低速、高导的弱化层。在下地壳,25—30km深处,物质分异形成了一个界面,它也许把地壳岩石与基性(幔源岩)岩分离开。莫霍(M)界面的性质明显地呈二元性,即化学的和相变的。在地质演化过程中相变成分体现在界面变动之中:它随升温而抬升,随地壳冷却而凹陷。在古地台,M界面限于岩石处于真正塑性状态的深度:这使液体不能透过岩石从而引起物理化学性质的变化。 展开更多
关键词 地台 地质演化 地盾 科拉半岛 沉积盆地 界面性质 基性 大陆岩石圈 软流层 化学分异
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相界上的地震波的不连续性与物性参数效应
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作者 H.Stiller 韩雨 《地球物理学进展》 CSCD 1989年第2期104-108,共5页
作者讨论了地幔中物相转变层的形状、结构和厚度。这些相界能影响下行地震波的速度,对流板块中相变的动力学效应会产生地幔对流过程中的化学分异。
关键词 物性参数 相界 化学分异 地幔对流 不连续性 地球物理 地球内部结构 平衡方程 超塑性 转换带
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Comparison on the Chemical Compositions in the K326 Tobacco from Different Tobacco-planting Areas of Yunnan Province 被引量:11
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作者 王岚 杨继周 +8 位作者 蒋美红 段俊杰 卢叶 敖金成 马彦清 李继飞 王涛 林楠 邓国宾 《Agricultural Science & Technology》 CAS 2012年第1期139-142,共4页
[Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used ... [Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used to detect the con- ventional chemical compositions, and SPSS 17.0 statistical package was used to conduct data statistical analysis and variance analysis. [Result] Significant differences were existed among most of the indicators for conventional chemical compositions of K326 tobacco in different areas: the differences of total sugar, reducing sugar and nicotine reached a high Significant level; potassium ion and total nitrogen differences reached a significant level, while there was no significant difference in chlorine ion. Most of the conventional chemical compositions in K326 B2F tabacco planted in Yuxi region and those planted in Qujing, Dali and Chuxiong were significantly different. The total sugar, reducing sugar and nicotine contents of tobacco planted in eastern Yunnan, central Yunnan and western Yunnan were significantly different; while the conventional chemical compositions contents in the tobacco planted in Chuxiong and Dali, which all belong to western Yunnan, showed no obvious significant difference, indicating different ecological environments in large area had a great impact on the tobacco of Yunnan Province. [Conclusion] It revealed the regional characteristics of the conventional chemical compositions in K326 flue-cured tobacco leaves from Yunnan Province, providing references for the cigarette blending and production of high-quality tobacco with characteristics. 展开更多
关键词 K326 B2F Conventional chemical compositions DIFFERENCE
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Small-Scale Spatial Variability of Soil Nutrients and Vegetation Properties in Semi-Arid Northern China 被引量:8
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作者 CHEN Fu-Sheng ZENG De-Hui HE Xing-Yuan 《Pedosphere》 SCIE CAS CSCD 2006年第6期778-787,共10页
A field experiment was conducted at Kezuohouqi County, Inner Mongolia Autonomous Region of China, which was located on the southeastern edge of the Horqin Sandy Land, to study the spatial variability of soil nutrients... A field experiment was conducted at Kezuohouqi County, Inner Mongolia Autonomous Region of China, which was located on the southeastern edge of the Horqin Sandy Land, to study the spatial variability of soil nutrients for a smallscale, nutrient-poor, sandy site in a semi-arid region of northern China; to investigate whether or not there were 'islands of fertility' at the experimental site; and to determine the key nutrient elements that sustained ecosystem stability. Results obtained from geostatistical analysis indicated that the spatial distribution pattern of soil total nitrogen (STN) was far different from those of soil organic matter (SOM), total phosphorus (STP), and total potassium (STK). Compared to SOM, STP, and STK, STN had a lower structural heterogeneity ratio and a longer range, while other elements were all similar. In addition, STN had an isotropic spatial structure, whereas the others had an anisotropic spatial structure. The spatial structure patterns of herbage species, cover,and height also differed, indicating that spatial variability was subjected to different ecological factors. Differences in the spatial variability patterns among soil nutrients and vegetation properties showed that soil nutrients for a small-scale were not the primary limiting factors that influenced herbage spatial distribution patterns. Incorporating spatial distribution patterns of tree species, namely, Pinus sylvestris var. mongolica Litv. and shrub Lespedeza bicolor Turcz. in a research plot and using fractal dimension,SOM, STP, and STK were shown to contribute to the 'islands of fertility' phenomenon, however STN was not, possibly meaning that nitrogen was a key limiting element. Therefore, during restoration of similar ecosystems more attention should be given to soil nitrogen. 展开更多
关键词 Pinus sylvestris war. mongolica Litv. semi-arid region soil nutrients spatial variability species richness
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One-pot synthesis and structural characterization of urea-isobutyraldehyde-formaldehyde resin 被引量:1
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作者 张一甫 曾幸荣 《Journal of Central South University》 SCIE EI CAS 2009年第1期80-84,共5页
Urea-isobutyraldehyde-formaldehyde (UIF) resin was synthesized from urea, isobutyraldehyde, and formaldehyde using sulfuric acid as a catalyst by one pot method. The effects of molar ratios of isobutyraldehyde to form... Urea-isobutyraldehyde-formaldehyde (UIF) resin was synthesized from urea, isobutyraldehyde, and formaldehyde using sulfuric acid as a catalyst by one pot method. The effects of molar ratios of isobutyraldehyde to formaldehyde (n(I)/n(F)) and aldehyde to urea (n(A)/n(U)) on the yield, hydroxyl value (vs KOH) and softening point of the resin were investigated. The structure of the resin was characterized by FT-IR, 1H-NMR and 13C-NMR. The results show that when the molar ratio of urea to isobutyraldehyde to formaldehyde (n(U)/n(I)/n(F)) is 1.0/3.0/3.0, the yield UIF resin is 67.1%, and the softening point and hydroxyl value are 88 ℃ and 37 mg/g, respectively. The FT-IR, 1H-NMR and 13C-NMR results show that the lactam is formed by aminomethylation from urea, isobutyraldehyde, and formaldehyde. 展开更多
关键词 UREA ISOBUTYRALDEHYDE FORMALDEHYDE RESIN synthesis structural characterization
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Mineralization-related geochemical anomalies derived from stream sediment geochemical data using multifractal analysis in Pangxidong area of Qinzhou-Hangzhou tectonic joint belt, Guangdong Province, China 被引量:5
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作者 张焱 周永章 +8 位作者 王林峰 王正海 何俊国 安燕飞 李红中 曾长育 梁锦 吕文超 高乐 《Journal of Central South University》 SCIE EI CAS 2013年第1期184-192,共9页
Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies ... Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies into their component patterns were described. A set of stream sediment geochemical data was obtained for 1 880 km 2 of the Pangxidong area, which is in the southern part of the recently recognized Qinzhou-Hangzhou joint tectonic belt. This belt crosses southern China and tends to the northwest (NE) direction. The total number of collected samples was 7 236, and the concentrations of Ag, Au, Cu, As, Pb and Zn were measured for each sample. The spatial combination distribution law of geochemical elements and principal component analysis (PCA) were used to construct combination models for the identification of combinations of geochemical anomalies. Spectrum-area (S-A) fractal modeling was used to strengthen weak anomalies and separate them from the background. Composite anomaly modeling was combined with fractal filtering techniques to process and analyze the geochemical data. The raster maps of Au, Ag, Cu, As, Pb and Zn were obtained by the multifractal inverse distance weighted (MIDW) method. PCA was used to combine the Au, Ag, Cu, As, Pb, and Zn concentration values. The S-A fractal method was used to decompose the first component pattern achieved by the PCA. The results show that combination anomalies from a combination of variables coincide with the known mineralization of the study area. Although the combination anomalies cannot reflect local anomalies closely enough, high-anomaly areas indicate good sites for further exploration for unknown deposits. On this basis, anomaly and background separation from combination anomalies using fractal filtering techniques can provide guidance for later work. 展开更多
关键词 geochemical anomalies fractal modeling principal component analysis Qinzhou-Hangzhou joint tectonic belt streamsediments
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Direct Z-scheme photochemical hybrid systems:Loading porphyrin-based metal-organic cages on graphitic-C_(3)N_(4) to dramatically enhance photocatalytic hydrogen evolution 被引量:5
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作者 Yang Lei Jian-Feng Huang +3 位作者 Xin-Ao Li Chu-Ying Lv Chao-Ping Hou Jun-Min Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2249-2258,共10页
The rational design of photochemical molecular device(PMD)and its hybrid system has great potential in improving the activity of photocatalytic hydrogen production.A series of Pd6L3 type metal-organic cages,denoted as... The rational design of photochemical molecular device(PMD)and its hybrid system has great potential in improving the activity of photocatalytic hydrogen production.A series of Pd6L3 type metal-organic cages,denoted as MOC-Py-M(M=H,Cu,and Zn),are designed for PMDs by combining metalloporphyrin-based ligands with catalytically active Pd^(2+)centers.These metal-organic cages(MOCs)are first successfully hybridized with graphitic carbon nitride(g-C_(3)N_(4))to form direct Z-scheme heterogeneous MOC-Py-M/g-C_(3)N_(4)(M=H,Cu,and Zn)photocatalysts via π-πinteractions.Benefiting from its better light absorption ability,the MOC-Py-Zn/g-C_(3)N_(4) catalyst exhibits high H_(2) production activity under visible light(10348μmol g^(-1) h^(-1)),far superior to MOC-Py-H/g-C_(3)N_(4) and MOC-Py-Cu/g-C_(3)N_(4).Moreover,the MOC-Py-Zn/g-C_(3)N_(4) system obtains an enhanced turn over number(TON)value of 32616 within 100 h,outperforming the homogenous MOC-Py-Zn(TON of 507 within 100 h),which is one of the highest photochemical hybrid systems based on MOC for visible-light-driven hydrogen generation.This confirms the direct Z-scheme heterostructure can promote effective charge transfer,expand the visible light absorption region,and protect the cages from decomposition in MOC-Py-Zn/g-C_(3)N_(4).This work presents a creative example that direct Z-scheme PMD-based systems for effective and persistent hydrogen generation from water under visible light are obtained by heterogenization approach using homogeneous porphyrin-based MOCs and g-C_(3)N_(4) semiconductors. 展开更多
关键词 Porphyrin-based metal-organic cage g-C_(3)N_(4) Photochemical molecular device Direct Z-scheme heterostructure Photocatalytic hydrogen evolution from water
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Grasshoppers Sphenarium Purpurascens Ch Source of Proteins and Essential Amino Acids
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作者 Melo-Ruiz Virginia Quirino-Barreda Tomas Garcia-Nunez Maritza Diaz-Garcia Rafael Sanchez-Herrera Karina Schettino-Bermudez Beatriz 《Journal of Chemistry and Chemical Engineering》 2015年第7期472-476,共5页
Protein malnutrition is quite common worldwide; its deficiency has adverse effects in all organs. Edible insect's traditional cultural food, commonly consumed in rural communities, now intake is also being incorporat... Protein malnutrition is quite common worldwide; its deficiency has adverse effects in all organs. Edible insect's traditional cultural food, commonly consumed in rural communities, now intake is also being incorporated in some countries. Grasshoppers comprise proteins, the building blocks of AA (amino acids), that are one of the five classes of complex biomolecules found in cells and tissues that play an important role in human metabolism and nutrition. This research was conducted to determine proximal composition of Sphenarium purpurascens Ch, grasshoppers, focused on proteins and AA. Sampling was performed during autumn, 2013, in Oaxaca State. Dry raw adult insects were ground and proceeded to macro molecules proximal analysis, protein by Kjeldahl AOAC (Association of Official Analytical Chemists) method and essential AA in a Beckman 6300 equipment. Obtained data were: total proteins 71.56%; lipids 8.14%; minerals 3.52%; fiber 7.48%; soluble carbohydrates 9.30%. Essential AA (mg/16 g-N): isoleucine 4.5; leucine 8.1; lysine 5.4; methionine + cysteine 5.1; phenylalanine + tyrosine 8.5; threonine 3.5; tryptophan 0.6; valine 5.5. Sphenarium purpurascens Ch, Grasshoppers represent a good source of proteins and essential AA that can grow almost everywhere, available mostly all year round and affordable to all social groups, thus being a good option to improve human health. 展开更多
关键词 PROTEINS essential AA NUTRITION GRASSHOPPERS Sphenarium purpurascen.
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AN ALGORITHM FOR DICTIONARY GENERATION IN SPARSE REPRESENTATION
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作者 Xie Zongbo Feng Jiuchao 《Journal of Electronics(China)》 2009年第6期836-841,共6页
The K-COD (K-Complete Orthogonal Decomposition) algorithm for generating adaptive dictionary for signals sparse representation in the framework of K-means clustering is proposed in this paper,in which rank one approxi... The K-COD (K-Complete Orthogonal Decomposition) algorithm for generating adaptive dictionary for signals sparse representation in the framework of K-means clustering is proposed in this paper,in which rank one approximation for components assembling signals based on COD and K-means clustering based on chaotic random search are well utilized. The results of synthetic test and empirical experiment for the real data show that the proposed algorithm outperforms recently reported alternatives: K-Singular Value Decomposition (K-SVD) algorithm and Method of Optimal Directions (MOD) algorithm. 展开更多
关键词 Sparse representation K-Complete Orthogonal Decomposition (K-COD) Adaptivedictionary
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