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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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Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
International Journal of Applied Linguistics, EarlyView.ABSTRACT Artificial intelligence (AI) tools now permeate English academic writing. However, evidence on how feedback modalities align with student differences and with psychological mechanisms remains limited. Prior work often reduced learning styles to simple matches with delivery modes and treated learning engagement and writing anxiety as peripheral.
Yi Ren +3 more
wiley +1 more source
International Journal of Applied Linguistics, EarlyView.ABSTRACT This study examines how foreign language teachers’ beliefs about the medium of instruction and translanguaging evolve over time by revisiting three in‐service teachers twelve years after their initial interviews. Using a qualitative longitudinal design, the study traces how translanguaging was initially framed as pedagogically deficient but ...
Danping Wang
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International Journal of Applied Linguistics, EarlyView.ABSTRACT With the increasing number of Chinese international students in Australian universities, intercultural competence has become a critical factor influencing their interactions with Australian tutors in university classroom settings. Existing research often examines students’ intercultural competence from a single‐method or single‐perspective ...
Jiangyu Han, Linda Tsung
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Facets of Crises: How Problem Indicators and Public Perceptions Affect Policy Change
Policy Studies Journal, EarlyView.ABSTRACT Crises are widely acknowledged as catalysts for policy change. Yet, our understanding of the policy effects of crises remains limited. Why do only some crises lead to major changes, while significant policy changes also occur during seemingly non‐crisis periods?
Constantin Kaplaner +6 more
wiley +1 more source
Measuring Governance or Wealth? Construct Validation of AI Readiness Indices
Policy &Internet, Volume 18, Issue 3, September 2026.ABSTRACT Many are the promises of artificial intelligence and the indices claiming to measure government readiness for it. This study provides the first construct validity investigation of the Oxford Insights Government AI Readiness Index, the Tortoise Global AI Index, and the IMF AI Preparedness Index, using a nine‐test battery and drawing on ...
Anis Ben Brik
wiley +1 more source
Gongye shui chuli, 2003 采用三氯化铁作为混凝剂，通过变化投加量和pH，考察各个分子质量区间的DOC和UV254的变化情况，了解强化混凝去除有机物的效果和机理。增加混凝剂的投加量能有效地促进各分子质量区间的UV254的去除，但对DOC的去除效果较差。三氯化铁对小分子质量的有机物具有很好的去除效果，总去除率的至少50％为去除小分子质量有机物所贡献。降低pH能有效地促进各分子质量区间的DOC和UV254的去除，去除有机物的最佳pH为5．5。在最佳的pH下，小分子质量的有机物得到了最大限度的去除。
董秉直, 曹达文, 范瑾初
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