Effects of composition and structure of alginates on adsorption of divalent metals

Results of a series of experiments (on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of different composition and block structure) conducted in this systematic study of the effects of the composition and structure of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of theM/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu²⁺ ion decrease with the increase of the G-block or the average length of the G-block and the total adsorption capacity of alginic acid is found to vary in the same order as theF _MM(diad frequency) in alginate in the mixed solution of Sr²⁺, Ba²⁺ and Cd²⁺. Contribution No. 2166 from the Institute of Oceanology, Chinese Academy of Sciences.     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861     

Why are the continents just so…?

Variations in gravitational potential energy contribute to the intraplate stress field thereby providing the means by which lithospheric density structure is communicated at the plate scale. In this light, the near equivalence in the gravitational potential energy of typical continental lithosphere with the mid‐ocean ridges is particularly intriguing. Assuming this equivalence is not simply a chance outcome of continental growth, it then probably involves long‐term modulation of the density configuration of the continents via stress regimes that are able to induce significant strains over geological time. Following this notion, this work explores the possibility that the emergence of a chemically, thermally and mechanically structured continental lithosphere reflects a set of thermally sensitive feedback mechanisms in response to Wilson cycle oscillatory forcing about an ambient stress state set by the mid‐ocean ridge system. Such a hypothesis requires the continents are weak enough to sustain long‐term (10⁸ years) strain rates of the order of ～10^?17 s^?1 as suggested by observations that continental lithosphere is almost everywhere critically stressed, by estimates of seismogenic strain rates in stable continental interiors such as Australia and by the low‐temperature thermochronological record of the continents that requires significant relief generation on the 10⁸ year time‐scale. Furthermore, this notion provides a mechanism that helps explain interpretations of recently published heat flow data that imply the distribution of heat‐producing elements within the continents may be tuned to produce a characteristic thermal regime at Moho depths.     

煤矿复采量与动用量和“三率”关系研究

通过分析煤炭资源复采量、复损量与当期（年）动用量、历年累计动用量、当期（年）采出量、当期（年）损失量之间的关系,提出了复采量计算公式,并阐述了复采量与生产矿井＂三率＂之间的关系。分析认为复采量参与当期（年）＂三率＂计算,能够确保当期（年）＂三率＂统计的真实性、准确性、合理性,从而提升煤炭资源储量管理水平和质量,同时建议修订生产矿井储量管理规程、矿井地质规范。     

Mineral Components and Anti-oxidant Activities of Tropical Seaweeds

Seaweeds are known to hold substances of high nutritional value; they are the richest resources of minerals important to the biochemical reactions in the human body. Seaweeds also hold non-nutrient compounds like dietary fiber and polyphenols. However, there is not enough information on the mineral compounds of tropical seaweeds. Also we are interested in the antioxidant activities of seaweeds, especially those in the tropical area. In this study, Indonesian green, brown and red algae were used as experimental materials with their mineral components analyzed by using an atomic absorption spectrophotometer. The catechins and flavonoids of these seaweeds were extracted with methanol and analyzed by high performance liquid chromatography （HPLC） ; the anti-oxidant activities of these seaweeds were evaluated in a fish oil emulsion system. The mineral components of tropical seaweeds are dominated by calcium, potassium and sodium, as well as small amounts of copper, iron and zinc. A green alga usually contains epigallocatechin, gallocatechin, epigallocatechin gallate and catechin. However, catechin and its isomers are not found in some green and red algae. In the presence of a ferrous ion catalyst, all the methanol extracts from the seaweeds show significantly lower peroxide values of the emulsion than the control, and that of a green alga shows the strongest anti-oxidant extract of this alga, which is significantly different from activity. The highest chelation on ferrous ions is also found in the the other methanol extracts in both 3 and 24 h incubations.     

东北三省粮食主产区农业比较优势与增长 优势时空演变研究

采用区位商和增长商指数,对1990—2018年黑龙江、吉林和辽宁三省的农业,及种植业、林业、畜牧业和渔业的比较优势和增长优势进行研究。结果表明：①从比较优势看,黑龙江省的农业、种植业、畜牧业和林业,吉林省的畜牧业,以及辽宁省的渔业和畜牧业,在全国具有突出的比较优势;东北三省的玉米、黑龙江省的大豆,及黑龙江和吉林省的牛肉生产具有显著的比较优势。②从增长优势看,1990—2018年,东北三省的种植业经济增速迟缓,而畜牧业经济具有明显的部门增长优势和区域增长优势,且增长优势突出,发展潜力较大。③从空间格局看,东北三省有75%的地级市农业具有比较优势;72%的地级市畜牧业产值增速高于全国平均水平,具有部门增长优势,优势突出。尽管东北三省种植业在全国的比较优势较强,但其产值增长速度相对迟缓。为推进粮食主产区农业发展,应提高现代农业发展水平,促进农业综合发展。     

建库与制图数据一体化生产与管理技术的研究与实践

本文通过对目前建库与制图数据生产与管理的现状,以及这两种数据特点的分析,阐明了建库与制图数据生产与管理一体化的真正含义和一体化空间数据模型的内容,通过在建库与制图数据一体化软件平台--Map-Store基础测绘版上的实践,总结了建库与制图数据一体化工艺方法和质量控制,在建库与制图数据一体化数据管理的基础上实现两种数据快...     

辽宁水稻主产区稻瘟病发生特征分析

利用1999-2012年辽宁省8个水稻主产区（17个观测点）的稻瘟病资料,分析辽宁省水稻主产区稻瘟病的发生特征及发展趋势。结果表明：2001年、2003年和2010年辽宁地区水稻产量显著下降,水稻生产受稻瘟病影响较大。2011年辽宁水稻种植主要集中在沈阳、盘锦、铁岭、辽阳、丹东和营口地区,其余地区也有少量种植。2001年辽宁稻瘟病（主要为穗颈瘟）发生严重,发病率为27.7 %。稻瘟病主要在新宾和清原发生严重,平均发病率分别为17.0 %和16.4 %。辽宁不同熟期水稻以中早熟品种稻瘟病发生严重,平均发病率为10.1 %。辽宁不同区域以辽东地区水稻稻瘟病发生严重,平均发病率为11.2 %。     

光纤光栅技术在工程变形监测中的应用

介绍了光纤光栅技术在工程变形监测中的应用,简述了光纤光栅监测的技术原理及光纤光栅的制作方法。     

枸杞岛海藻场冬季细菌群落结构分析

从枸杞岛海藻场和对照点贻贝场分别采取表层及底层水样,利用细菌通用引物,提取样品总DNA进行聚合酶链式反应(PCR)扩增,采用16SrDNA文库技术,对其细菌群落进行鉴定和分析。结果表明,海藻场表层和底层细菌群落分为5和6个门,贻贝场表层和底层细菌群落分为3和4个门,海藻场中细菌分类门数多于贻贝场内,优势菌均为变形细菌门,分别占克隆文库的比例为40.7%、50%、59.1%和48.1%。γ-变形菌纲为变形细菌门的优势亚群,各个文库中均含有许多未确定其分类的序列,即含有许多未被认知的微生物类群。变形菌门、厚壁菌门和放线菌门为所有水样共有,但在水层垂直分布及不同地理位置间存在较大差异。不同功能类群可能与其特殊生境密切相关。