Results 41 to 50 of about 26,472 (207)
Preparation and Photoluminescence of Praseodymium-Doped Silicon Aluminum Oxynitride Phosphors by Polymer-Derived Method [PDF]
, 2016 应用先驱体转化法制备稀土掺杂硅基氮氧化物荧光粉，可以改善传统的固相反应法所需要的高温高压等苛刻条件。掺镨含铝硅基氮氧化物红色荧光粉具有较好的发光稳定性及化学稳定性，在显示照明领域具有潜在的应用价值。目前，尚没有先驱体转化法制备掺镨含铝硅基氮氧化物红色荧光粉的报道，因此，有必要探讨先驱体转化法制备该荧光粉的合成工艺及参数。本论文采用聚碳硅烷、乙酰丙酮镨和乙酰丙酮铝为原料，通过聚合反应得到先驱体，在氨气中经氮化实现有机-无机转化，再经结晶制备掺镨含铝硅基氮氧化物荧光粉。系统研究了烧结温度、投料原子比 ...
余辉
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Low conductivity and poor oxygen reduction reaction (ORR) catalytic activity limit the bifunctional catalytic performance of layered double hydroxide (LDH) in zinc–air batteries. In this work, an efficient bifunctional electrocatalyst was prepared by loading nitrogen and phosphorus co‐doped carbon quantum dots (NPCQDs) onto a cationic‐vacancy ...
Wenhao Tang +4 more
wiley +1 more source
2010-2018年我国14个典型湖泊氮、磷变化特征及受人类活动的影响
Shuitu Baochi Xuebao, 2010 湖泊水污染情势对于湖泊的水功能发挥有指示意义。为研究过去近10年来我国典型湖泊中氮、磷浓度变化特征及水质情况,并探讨人类各领域活动对其的影响,收集了2010—2018年五大湖区14个典型湖泊的总氮与总磷浓度数据以及湖泊所在地级市的人口及经济数据。结果表明:(1)过去近10年我国五大湖区湖泊的总氮及总磷浓度整体上呈微弱下降趋势。(2)五大湖区水质的区域差异性显著,东部平原湖区水质较差,青藏高原湖区水质情况最优,而云贵高原湖区中湖泊水质情况差异较大。(3)人类活动对我国湖泊氮、磷浓度的影响很大 ...
周楠, 徐学选, 袁志友
doaj
Different forms of nitrogen contents and their vertical variations of transformation modes of the sediments of Lake Yuehu, Wuhan [PDF]
, 2008 Vertical distributions of nitrogen contents, net nitrification rates, net N-mineralization rates and nitrate reductase activities in sediments of Lake Yuehu in June, 2005, were described on basis of four samples from the lake.
Chen Guoyuan +5 more
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Developing efficient catalytic thermal desorption systems is of great significance in the field of sustainable soil remediation. Herein, novel Mn–Ce solid solution modified Co3O4 nanocrystals were successfully prepared for the removal of perfluorooctanoic acid (PFOA) in soil.
Yu‐Hao Liu +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2007 利用冬春季沉水植物菹草构建的阶梯式水生植物系统研究了其对水体悬浮泥沙及氮、磷污染物的净化效果。结果表明：由菹草构成的生态物理模型系统对挟沙水体氮、磷负荷以及泥沙含量具有较好的改善作用,菹草系统前后总氮负荷分别为0.746 mg/L和0.622 mg/L,去除率为16.57%,其中菹草净化率占6.67%;停留时间分别为24 h和48 h时,菹草系统对总磷的净化百分率分别为18.52%和22.22%,其中菹草对总磷的净化作用分别占10.83%和6.84%,因此,菹草系统对挟沙水体中氮、磷的净化 ...
郭长城, 喻国华, 王国祥
doaj
Land-use Effect and Seasonal Hydrologic Controls on Nitrogen Export in Typical Sub-watersheds within Jiulong River Watershed [PDF]
, 2016 在过去的几十年里，世界范围的大部分地区都经历了由于进入近海的河流氮通量的大量增加而导致的富营养化和其它生态损害。氮、磷作为限制性营养盐，控制着河流－近海系统富营养化，威胁着我们所依赖的生态系统服务与功能。河流营养盐状况是植被、土壤、地形、气候、土地利用状况等自然和人为因素综合作用的结果，这些因素在不同时空尺度内交互作用，使得河流营养盐输出的影响机制研究更具挑战性。本研究开展亚热带流域氮输出对土地利用及水文状况季节性变动的响应，可为流域综合管理和区域用水安全提供科技支撑。 本研究通过现场监测、GIS技术 ...
赵盼盼
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Nitrogen Anchoring Effect Triggering Improved Reversible Hydrogen Storage of Mg(BH4)2
Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT This research uncovered the influence of nitrogen‐doped MXene Ti3CN on the reversible hydrogen storage properties of Mg(BH4)2. The Mg(BH4)2‐20Ti3CN composite began releasing hydrogen at a temperature of 80°C. In addition, the composite discharged over 8.8 wt% hydrogen at a comparatively lower temperature of 270°C, whereas the pure Mg(BH4)2 ...
Zhen‐Xuan Ma +7 more
wiley +1 more source
Shuitu Baochi Xuebao, 2011 采用田间小区定位试验研究自然降雨条件下稻秸全量还田对稻麦两熟农田麦季养分径流流失特征的影响。结果表明:麦季径流水量可达2 185.05 m3/hm2,秸秆还田(T1)处理可降低径流水量4.43%(p>0.05);常规施肥(T0)条件下,每1 hm2麦田径流流失全N(TN)和全P(TP)总量分别为30.90,3.00 kg,流失率分别达13.73%和3.34%;较T0处理而言,T1、T2(秸秆还田减肥)处理不仅减少TN和TP流失量分别达15.95%,33.50%和13.98%,15.71 ...
郭智, 周炜, 陈留根, 郑建初
doaj
Altruism and the Care of Elderly Parents: Evidence from Japanese Families [PDF]
This paper analyzes what adult children would do for their parents were they frail and in need of long-term care. Focusing on the special case of parents' illness, the paper then investigates altruism in Japanese children.
Fumio Ohtake, Miki Kohara
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