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Fenmo yejin jishu, 2022 表面改性是使材料表面获得与其基体不同微观组织的处理技术，能够有效调控材料表面的力学性能。因此，将表面改性方法应用于改善硬质合金表面的微观组织，能够有效避免均匀结构硬质合金显微结构–宏观性能的局限性，为制备高性能非均匀结构硬质合金提供技术方案。由于硬质合金表面改性研究的起步较晚且表面改性方法较多，表面改性方法的选取及其改性机理依然面临思路不清的问题。本文总结了化学表面改性梯度硬质合金的材料体系、制备机理、微观结构及力学性能，概括了物理表面改性得到的硬质合金涂层方法与功能 ...
陈健 +4 more
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Gongye shui chuli, 2021 研究了组合改性沸石的最佳制备方法，以及不同改性方式和pH对改性沸石除磷效果的影响。通过吸附动力学与吸附等温线探究其吸附机理并使用扫描电镜对改性前后的沸石进行表征。结果表明，最佳的改性方案为2.0 mol/L NaOH溶液和2.0 mol/L聚合氯化铝（PAC）溶液组合改性。当废水pH=7时该改性沸石除磷效果最佳，此时除磷率为98.74%，其吸附符合准二级动力学方程和Langmuir模型。扫描电镜表征结果表明，碱改性和铝改性均可改变沸石的孔隙结构，增加吸附点位。
徐丽, 徐子祥
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Zhongguo youzhi, 2023 植物油料蛋白胶黏剂具有来源广泛、无毒、可再生及制备简单等优点，但胶接强度低、耐水性能差、易霉变等问题限制了其发展和应用。综述了近年来几种主要植物油料蛋白胶黏剂如大豆蛋白胶黏剂、花生蛋白胶黏剂、棉籽蛋白胶黏剂等在木材行业的研究和应用现状，重点阐述了提高植物油料蛋白胶黏剂耐水性能的改性方法，包括物理改性、变性剂改性、接枝改性、交联改性、仿生改性、酶改性、纳米材料改性、复合改性等，指出了植物油料蛋白胶黏剂存在的问题，并对未来发展方向和应用前景进行了展望。Plant protein-based ...
刘欣锐，陈惠，高强，李建章 LIU Xinrui， CHEN Hui， GAO Qiang， LI Jianzhang
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Beyond Universalism: A Contextual Approach to Comparative Public Administration
Public Administration and Development, EarlyView.ABSTRACT In this essay, I advocate for a contextual approach to comparative public administration, arguing that effective governance reform requires moving away from universal models to embrace local political, socioeconomic, and institutional realities.
XiaoHu Wang
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Organ‐specific ozone and nitrogen legacies strengthen substrate control over litter decomposition
Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Elevated tropospheric ozone (O3) and nitrogen (N) deposition are concurrent atmospheric changes that strongly influence terrestrial carbon cycling, yet their combined effects on below‐ground decomposition remain poorly understood.
Xiaofan Hou +8 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Root activity creates unique microbial hotspots in the rhizosphere by influencing the metabolic activities of surrounding soil microorganisms, profoundly regulating the dynamics of soil organic carbon (SOC). However, how root economic strategies affect the formation and
Qiyu Tan +8 more
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Housing policies and market returns in China: Evidence from a novel policy index
Real Estate Economics, EarlyView.Abstract This article examines the relationship between housing policy interventions and market returns in China with a novel policy index. Using natural language processing techniques, we construct a sentence‐level policy index based on government policy documents from 2008 to 2024.
Siu Kei Wong, Yumou Wang
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When and why to give shorebirds a head start
Conservation Biology, EarlyView.Abstract Headstarting is a translocation technique involving the hatching or rearing of wild eggs or young in captivity and the release of those individuals back to the wild at or before independence. It has been trialed as a conservation intervention for shorebirds over recent decades to improve the population trend of target populations by increasing
Lynda Donaldson +4 more
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Gongye shui chuli, 2017 对比了酸改性、碱改性和接枝共聚改性对玉米秸秆吸附氨氮性能的影响。结果表明，当初始氨氮质量浓度为200 mg/L时，玉米秸秆经酸改性、碱改性和接枝共聚改性的最大氨氮平衡吸附量分别达到23.4、26.4、33.8 mg/g，较未改性时分别提高55.0%、74.8%和123.8%，改性吸附效果为接枝共聚改性 > 碱改性 > 酸改性。玉米秸秆对氨氮的吸附过程可用Langmuir和Freundlich吸附等温模型描述，符合伪二级动力学方程。经过改性处理后△G降低，对氨氮的吸附变得更加容易。
张吉强, 郑平
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Gongye shui chuli, 2021 以水产业中产生的虾壳为原料进行改性，通过静态吸附实验探究H2O2改性后的虾壳粉对水中U（Ⅵ）的吸附影响因素。结果表明，当U（Ⅵ）溶液pH=3，改性虾壳粉投加量为0.2 g/L，U（Ⅵ）溶液质量浓度为10 mg/L，吸附时间为120 min时，改性虾壳粉对U（Ⅵ）的吸附量达到48.58 mg/g，pH对改性虾壳粉吸附U（Ⅵ）有较大影响。对吸附过程中的动力学分析以及吸附前后的改性虾壳粉的SEM、FTIR等表征结果表明：改性虾壳粉对U（Ⅵ）的吸附过程符合准一级动力学方程和Freundlich吸附等温模型 ...
姜高峰 +3 more
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