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Determination of 9 Organotins in Food Contact Materials(食品接触材料中9种有机锡的检测) [PDF]
Shipin kexue jishu xuebao, 2021 An analytical method for simultaneous determination of organotins in food contact materials with different uses by gas chromatography-mass spectrometry was established.
QIAN Chong(钱冲) +6 more
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Shuitu Baochi Xuebao, 2022 为了探讨中国西北地区土壤有机质现状及影响因素,运用ArcGIS和地统计学结合的方法,研究西北地区土壤有机质的空间分布规律及其影响因素。结果表明:(1)研究区土壤有机质含量处于较低水平,3级及以下占68.94%,有机质变化范围为1.10~107.50 g/kg,均值为20.13 g/kg;通过半方差函数模型分析得到有机质的最适理论模型为球状模型。(2)通过绘制整个西北地区土壤有机质的空间分布图可知,研究区东部区域从宁夏、陕北至甘南、陕南,有机质含量呈现出梯级增加的趋势 ...
雷琪, 蒋洪丽, 吴淑芳, 冯浩
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Zhejiang Daxue xuebao. Lixue ban, 2023 在埋藏过程中，随着埋深的增加，细粒沉积岩的矿物组成、有机质形态、孔隙类型与质量分数等会发生一系列变化。为揭示其变化规律，对有机质热模拟的残样进行了扫描电镜、全岩X射线衍射、镜质体反射率（Ro）、岩石热解、有机碳质量分数等测试。发现在从室温（25 ℃）到550 ℃的升温过程中，有机质形态由团块状向条带状、团块状变化；黏土矿物由层片状逐渐向絮状转化；碳酸盐矿物溶蚀加剧，温度超过500 ℃后，出现溶蚀-沉淀现象；随着温度的升高，由有机质热演化产生的有机质孔的面积不断增加，在450~475 ℃时 ...
尹玲芝(YIN Lingzhi) +4 more
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Shuitu Baochi Xuebao, 2006 利用多目标地球化学调查方法，通过野外实地调查、大面积系统采集土壤表层、深层样品、测试分析和数理统计，探讨了三峡库区不同土壤类型深层和表层土壤中有机质含量分布特征。以紫色土为例探讨了不同分布高程、坡度和不同植被条件下对有机质含量的影响。结果表明：三峡库区土壤有机质含量总体上较低，均为矿质土壤。成土母质类型对土壤有机质含量影响明显，相同自然条件成土作用下，海相石灰岩母岩区的土壤有机质高于陆相砂、泥岩母岩区的土壤。在土地利用方式上，水耕模式有利于增加土壤有机质。地形高程、坡度对紫色土有机质分布影响明显 ...
钟远平, 唐将, WANG Li, 王力
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Greenhouse gas emissions from croplands of China [PDF]
, 2003 China possesses cropland of 1.33 million km 2. Cultivation of the cropland not only altered the biogeochemical cycles of carbon (C) and nitrogen (N) in the agroecosystems but also affected global climate.
Bohan, Liao +13 more
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Journal of Adolescence, EarlyView.ABSTRACT Introduction Following rapid iterations in media technologies, Chinese millennials (born between 1980 and 1995) find themselves in a paradoxical state where digital saturation exists alongside fatigue, making them central practitioners of digital minimalist behavior.
Chao Zhang, Yinze Hao, Jingwen Li
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Marine flavobacterium Gramella flava JLT2011 utilization polysaccharide of phytoplankton and characterization of new species of Pelagibaca bacterium [PDF]
, 2015 海洋浮游植物是海洋食物网的初级生产者，是海洋有机质重要分泌者。海洋浮游植物光合作用产生的有机质,通过海洋细菌分泌的一系列胞外酶等将颗粒有机质POM（ParticleOrganicMatter,POM）进一步代谢为生物可利用的溶解有机质（BioavailableDissolvedOrganicMatter,BDOM）。在这一个过程中噬纤维菌-黄杆菌-拟杆菌(Cytophaga-Flavobacterium-Bacteroides,CFB)菌群起着重大的作用。这类细菌形态多样，一般具有较强的运动性和粘附性 ...
林颖芳
core
Justice in coexistence: Pastoralism and large carnivores on the Qinghai‐Tibet Plateau
People and Nature, EarlyView.Abstract The conflict between livestock husbandry and large carnivore conservation presents significant challenges in grassland ecosystems worldwide. Achieving sustainable coexistence among herders, livestock and large carnivores requires reconciling diverse perspectives and interests through equitable, inclusive and fair processes that address both ...
Yufang Gao, Yue Yu
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Linking biochemical properties of particles to particle-attached and free-living bacterial community structure along the particle density gradient from freshwater to open ocean [PDF]
, 2016 海洋颗粒有机质(particulateorganicmatter，POM)作为初级生产力的承担者，是链接生物泵和微型生物碳泵的重要桥梁，在海洋物质和能量循环中扮演重要角色。海洋颗粒附着(particle-attached，PA)细菌能够寄居在颗粒物上，通过细菌水解酶作用将POM转化成溶解有机质(dissolvedorganicmatter，DOM)，在颗粒物周围形成羽流。POM在去除过程中直接为PA细菌提供底物，影响PA细菌群落组成，而颗粒物释放的小分子化合物则影响周围的浮游(free-living ...
肖伟
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop +8 more
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