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Policy Studies Journal, Volume 50, Issue 1, Page 111-142, February 2022., 2022 This paper contributes to the integration of the study of multiple (i) spatial scales, (ii) resource systems, and (iii) points in time in natural resource governance by introducing a strategy of layering action situations. In the Institutional Analysis and Development Framework, action situations can be studied singularly, in comparison, or as networks
Malte Möck +3 more
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Gongye shui chuli, 2022 以皇竹草为原料制备活性炭（PAC），采用氯氧化锆（ZrOCl2·8H2O）和十六烷基三甲基溴化铵（CTAB）对其联合改性，制备出复合材料Zr-CTAB-PAC，探讨了吸附剂投加量、接触时间、pH、磷酸盐和硝酸盐初始浓度等因素对Zr-CTAB-PAC吸附水中硝酸盐及磷酸盐性能的影响。结果显示，Zr-CTAB-PAC是一种比表面积大、含有多种含氧官能团的材料，可同时吸附水中的硝酸盐及磷酸盐。在pH为5~9、Zr-CTAB-PAC用量为0.3 g、初始磷酸盐和硝酸盐质量浓度分别为15 mg/L和30 mg/L、
李建敏 +6 more
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Metal oxide semiconductor‐supported noble metal nanoparticles are common sensing materials for gas sensors. However, the large size and their tendency to migrate at high temperatures often lead to inferior sensing sensitivity and stability. Herein, a salt‐assistant strategy is developed to prepare fully‐exposed Ir clusters on SnO2 nanorods ...
Yi Jiang +7 more
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Shuitu Baochi Xuebao, 2005 利用盆栽试验研究了尿素、硫酸铵、硝酸铵、碳酸氢铵和硝酸钙5种氮肥和用量对川西蒙山茶品质的影响。结果表明:肥料种类、肥料用量以及肥料种类与用量的交互作用对茶叶主要品质指标(可溶性糖除外)的影响极显著;不论施用何种氮肥,茶叶中的茶多酚、儿茶素和咖啡碱含量都有极显著的增加;各种氮肥用量为4g/盆时,茶多酚、儿茶素和咖啡碱含量较高;与施用其他种类的氮肥相比,尿素能极显著地提高茶叶中儿茶素和氨基酸的含量。施用硝态氮将能显著提高茶叶中硝酸盐和亚硝酸盐的含量,但随着硝态氮用量的增加,硝酸盐和亚硝酸盐的含量没有显著变化,
夏建国 李静 巩发永 吴德勇
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT The electrocatalytic reduction of nitrate (NO3ER) has emerged as a promising strategy for mitigating NO3− ${{\text{NO}}_{3}}^{-}$ pollution in wastewater while concurrently producing value‐added ammonia; however, its process is significantly hindered by the lack of highly efficient and low‐cost electrocatalysts. Herein, we proposed several non‐
Xue‐Shi Song +5 more
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Guanotrophy: Waterbirds Pay for Using Resources at Their Wintering Habitats 鸟粪营养学 ：水鸟在越冬栖息地使用资源后留下回报
Integrative Conservation, Volume 3, Issue 4, Page 382-397, December 2024.Significant waterbird colonisation was recorded in the wintering period (October through March in 2018–2019 and 2019–2020) in wetlands on Central Asian and East Australasian Flyways. Different limnochemical conditions influenced nitrate and phosphate concentrations.
Arkajyoti Mukherjee +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2008 纳米级零价铁(Fe0)同步处理Cu2+、Ni2+、Cr(VI)等重金属离子和硝酸根的实验中发现，硝酸盐对重金属离子的去除基本无影响，而不同重金属离子则对硝酸盐的去除有不同的影响.同步去除Cu2+和NO3-、Ni2+和NO3-时,与单独去除NO3-相比，Cu2+、Ni2+可以明显地提高硝酸盐的去除率和反应速度，并且Cu2+、Ni2+的初始浓度越高，NO3-的去除效果越好，反应速率常数kobs也越大.纳米级Fe0同步去除Cr(VI)和NO3-时，Cr(VI)阻碍了Fe0还原脱除硝酸盐反应的发生，当Cu2 ...
ZHANGZhen(张珍) +6 more
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Synthesis of 2-diethylamino-6-methyl-4-hydroxy-pyrimidine(中间体2-二乙胺基-6-甲基-4-羟基嘧啶的合成)
Zhejiang Daxue xuebao. Lixue ban, 2006 以二乙胍硝酸盐为原料，与乙酰乙酸乙酯环合制备了2-二乙胺基-6-甲基-4-羟基嘧啶，讨论了原料配比、反应温度及反应时间等因素对反应的影响，获得了较佳的反应条件.制备2-二乙胺基-6-甲基-4-羟基嘧啶的较佳的反应条件为：采用甲苯为溶剂，反应温度110 ℃，反应时间2 h，二乙胍硝酸盐与乙酰乙酸乙酯及乙醇钠的摩尔比为1：1.2 : 1.2.在较佳反应条件下，以二乙胍硝酸盐计，产品收率为91%，质量分数为99%.
TANCheng-xia(谭成侠) +3 more
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Zhongshan Daxue xuebao. Yixue kexue ban, 1980 据报道,仲胺与亚硝酸(或亚硝酸盐)在体内、外于适当的酸度下,均能合成强烈致癌物质—亚硝胺。合成亚硝胺的前身物质如胺类和亚硝酸盐等,广泛存在于食物中,因为胺类是蛋白质腐败时的分解产物,亚硝酸盐是在腌制肉类时和食盐一道加进去的;植物性食物中的硝酸盐经细菌的作用,也可以还原为亚硝酸盐,故测定食物中的仲胺在卫生分析及肿瘤病因学上有一定的意义。本文采用水蒸汽 ...
黄家琛
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Gongye shui chuli, 2003 研究利用一种化学脱氮方法,去除废水中高浓度的硝酸盐。其原理为金属物质还原废水中的硝酸盐生成亚硝酸盐,再利用酰胺类物质与亚硝酸盐反应生成氮气。试验表明,用锌和氨基磺酸两种物质与之反应生成氮气,达到去除硝酸盐的目的。结果表明,在停留时间为1.5～2h,反应pH为1及锌与氨基磺酸达到最佳投入比例时,使含硝酸氮的质量浓度为351～488mg/L的废水达到96%的去除率。
童娜, 杨新宇, 花绍龙, 张敏莉
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