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Calcium-based polymers for suppression of soil acidification by improving acid-buffering capacity and inhibiting nitrification

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Journal of Environmental Sciences 2024年第5期139卷 138-149页

作者： Fei Kang Yunshan meng yanning Ge Yun Zhang Haixiang Gao Xueqin Ren Jie Wang Shuwen Hu Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical regions.Biodegradable and environmentally friendly materials,such as calcium lignosulfonate(CaLS),calcium poly(aspartic acid)(PASP-Ca),and calcium polyγ-glutamic acid(γ-PGA-Ca),are known to effectively ameliorate soil acidity.However,their effectiveness in inhibiting soil acidification has not been studied.This study aimed to evaluate the effect of CaLS,PASP-Ca,andγ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly(i.e.,via nitrification)caused by the application of HNO_(3)and urea,respectively.For comparison,Ca(OH)_(2)and lignin were used as the inorganic and organic controls,respectively.Among the materials,γ-PGA-Ca drove the substantial improvements in the pH buffering capacity(pHBC)of the soil and exhibited the greatest potential in inhibiting HNO_(3)-induced soil acidification via protonation of carboxyl,complexing with Al~(3+),and cation exchange processes.Under acidification induced by urea,CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during incubation.Furthermore,the sharp reduction in the population sizes of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)confirmed the inhibition of nitrification via CaLS application.Therefore,compared to improving soil pHBC,CaLS may play a more important role in suppressing indirect acidification.Overall,γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO_(3) addition,whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting nitrification.In conclusion,these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.

关键词： Calcium-based polymer Soil acidification pH buffering capacity Nitrification inhibition

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科技报告政策细粒度知识图谱构建及应用研究

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情报理论与实践 2024年第7期47卷 170-180页

作者：支凤稳孟佳琪郑彦宁河北大学管理学院河北保定071002 中国科学技术信息研究所北京100038

[目的/意义]科技报告作为我国重要的科技信息资源,不断促进国家的科技创新发展。构建科技报告政策细粒度知识图谱,并探讨其应用价值,对了解、制定和优化相关的政策,保证科技报告质量,提升科技报告工作效率,促进国家科技创新具有重要意义... 详细信息

[目的/意义]科技报告作为我国重要的科技信息资源,不断促进国家的科技创新发展。构建科技报告政策细粒度知识图谱,并探讨其应用价值,对了解、制定和优化相关的政策,保证科技报告质量,提升科技报告工作效率,促进国家科技创新具有重要意义。[方法/过程]收集并整理近10年的科技报告政策,深入挖掘其基本信息和政策文本内容,利用SciAIEngine、Excel、Gephi等工具进行细粒度知识分类聚类,构建科技报告政策细粒度知识图谱。依据政策之间的细粒度知识关联情况,探究图谱在科技报告政策领域的应用价值。[结果/结论]细粒度知识图谱可用于科技报告政策的知识查询、知识统计和内容聚类分析,还可为政策优化提供一定的依据,未来可在科技报告制度建设、科技资源共享、知识产权保护和国家科技报告服务系统方面继续探究。研究虽有所不足,但对未来研究仍有一定的帮助与启发。

关键词：科技报告政策细粒度知识知识图谱政策优化

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中小企业竞争情报共享行为系统动力学分析

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情报杂志 2024年第5期43卷 191-200页

作者：张萌支凤稳王继月郑彦宁河北大学管理学院保定071002 中国科学技术信息研究所北京100038 沧州师范学院沧州061000

[研究目的]深入揭示我国中小企业竞争情报(Competitive Intelligence,CI)共享行为及其影响因素的动态变化趋势,以期为CI共享实践提供重要依据和建议。[研究方法]依据预期收益、共享成本、外部环境不确定性、资源依赖、信任、共享意愿与... 详细信息

[研究目的]深入揭示我国中小企业竞争情报(Competitive Intelligence,CI)共享行为及其影响因素的动态变化趋势,以期为CI共享实践提供重要依据和建议。[研究方法]依据预期收益、共享成本、外部环境不确定性、资源依赖、信任、共享意愿与中小企业CI共享行为之间的关系及实证结果,构建系统动力学模型,对中小企业CI共享行为进行仿真预测。[研究结论]中小企业CI共享行为前期受共享意愿和信任的影响较大,增加预期收益和共享成本,会提高中小企业对CI共享的资源依赖程度;后期受共享成本和外部环境不确定性的影响较大,并且会随着预期收益和共享成本的增加逐渐减少对CI共享的资源依赖。CI共享意愿较强的中小企业能够更快地提高共享行为发生的频率,并且其共享行为始终高于共享意愿较弱的中小企业。最后,提出促进中小企业CI共享的对策建议,有利于CI共享工作的开展。

关键词：竞争情报中小企业共享行为共享意愿系统动力学

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Genesis and Uranium Sources of Leucogranite-hosted Uranium Deposits in the Gaudeanmus Area, Central Damara Belt, Namibia: Study of Element and Nd Isotope Geochemistry

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2126-2137页

作者： FAN Honghai CHEN Jinyong WANG Shengyun ZHAO Jingyang GU Dazhao meng yanning Beijing Research Institute of Uranium Geology Key Laboratory of Uranium Resource Exploration and Evaluation Technology CNNC Department of Earth Sciences and State Key Lab of Mineral Deposit Research Nanjing University

This paper presents a systematic study of major and trace elements and Sm-Nd isotopes in leucogranites closely related to uranium mineralization in the Gaudeanmus area, Namibia. The results illustrate that the uraniferous leucogranites possess high SiO2 （68.8wt%-76.0wt%, average 73.1wt%） and K （4.05wt%-7.78wt%, average 5.94wt%） contents, and are sub-alkaline and metaluminous to weakly peraluminous, as reflected by A/CNK values of 0.96-1.07 with an average of 1.01. The leucogranites are rich in light rare earth elements （LREE/HREE = 2.53-7.71; （La/Yb）s = 2.14-10.40）, have moderate Eu depletion and high Rb/Sr ratios （2.03-5.50 with an average of 4.36）; meanwhile, they are enriched in Rb, K, Th, U and Pb, and depleted in Ba, Nb, Ta, and Sr. The tNd（t） values of uraninites range from -14.8 to -16.5, and the two-stage Nd model ages are 2.43-2.56 Ga. Detailed elemental and Sm-Nd isotopic geochemical characteristics suggest that the leucogranites were formed in a post- orogenic extensional environment. The U-rich pre-Damara basement was the main source of uranium during the primary mineralization event, which is disseminated in leucogranites, whereas the uranium mineralization in veins possibly resulted from remobilization of the primary uranium minerals.

关键词： uranium source of uranium Nd isotopes leucogranites Gaudeanmus Damara Belt

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Spatio-temporal framework of tectonic uplift stages of the Tibetan Plateau in Cenozoic

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Science China Earth Sciences 2011年第1期54卷 29-44页

作者： WANG GuoCan CAO Kai ZHANG KeXin WANG An LIU Chao meng yanning XU YaDong State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Faulty of Earth Sciences China University ofGeosciences Wuhan 430074 China The Bureau of Non-ferrous Geology of Liaoning Province Shenyang 110013 China

Four intensive uplift periods, i.e., 60–35, 25–17 and 12–8 Ma (but 18–13 Ma in the Himalayas of the southern Tibet), and since about 5 Ma, can be determined on the Tibetan Plateau by synthetical analysis of low-temperature thermo-chronology data, sedimentary deposit records, and structural deformation records of different areas. The strong tectonic uplift periods in different areas on the Tibetan Plateau are penecontemporaneous, except for the Himalayan area of the southern Tibet, where a rapid uplift and exhumation period, controlled by the activity of the South Tibetan Detachment System faults, occurred during 18–13 Ma. These strong uplift and exhumation periods correspond well to intensive deformation activity periods, suggesting tectonically-controlled uplift and exhumation. The deposit records, such as the distribution of coarse clastic sediments, the distribution of tectonically-controlled basins, stratigraphic discontinuousness or unconformity, and fault-controlled geomorphologic evolution, also match well with the strong uplift and exhumation periods. Expanding processes of the plateau are also discussed.

关键词：青藏高原新生代构造升阶框架时空喜马拉雅山脉构造隆升喜马拉雅地区

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人工湿地模块化基质脱氮除磷性能研究

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水处理技术 2024年第2期50卷 44-50页

作者：陈思佳黄丹高彦宁孟志国张国权大连理工大学环境学院辽宁大连116023 中船重工环境工程有限公司北京100039 中化上海沈化院科技有限公司上海201203

选取碱、Mg^(2+)和Zn^(2+)复合改性的沸石、石灰石和硅藻土为骨料,参照植生型多孔混凝土制作方法,制作了七种不同骨料体积比的模块化人工湿地基质。通过静态吸附实验对其脱氮除磷性能进行比较。筛选出三种模块化基质进行等温吸附实验和... 详细信息

选取碱、Mg^(2+)和Zn^(2+)复合改性的沸石、石灰石和硅藻土为骨料,参照植生型多孔混凝土制作方法,制作了七种不同骨料体积比的模块化人工湿地基质。通过静态吸附实验对其脱氮除磷性能进行比较。筛选出三种模块化基质进行等温吸附实验和动力学吸附实验,对其脱氮除磷机制进行研究。结果表明:以单一改性沸石为骨料的模块化基质脱NH_(4)^(+)-N效果最好,其理论最大吸附量为45.79 mg/g;以三种改性基质按体积比1∶1∶1配比为骨料制作的模块化基质除PO_(4)^(3-)-P效果最好,其理论最大吸附量为11.52 mg/g;准二级吸附动力学模型能更好地拟合三种基质脱氮除磷的吸附动力学过程,三种基质对NH_(4)^(+)-N和PO_(4)^(3-)-P的吸附速率均受化学吸附速率控制。

关键词：人工湿地基质改性生态混凝土脱氮除磷吸附

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Cenozoic sedimentary records and geochronological constraints of differential uplift of the Qinghai-Tibet Plateau

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Science China Earth Sciences 2008年第11期51卷 1658-1672页

作者： ZHANG KeXin WANG GuoCan CAO Kai LIU Chao XIANG ShuYuan HONG HanLie KOU XiaoHu XU YaDong CHEN FenNing meng yanning CHEN RuiMing Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Faulty of Earth Sciences China University of GeosciencesWuhan 430074China

Geological mapping data (1:250000) in the Qinghai-Tibet Plateau and its adjacent regions reveal the sediment sequences, distribution and tectonic evolution of the 92 Tertiary remnant basins. Southern Tibet and the Yecheng area in Xinjiang, located at southern and northwestern margins of the Qinghai-Tibet Plateau, respectively, were parts of the Neo-Tethys remnant sea in the Paleogene. In southern Tibet, both the subabyssal and abyssal sequences occur at the Gyangze, Saga, Guoyala, and Sangmai areas. The deep-water facies successions outcrop in the west, whereas the shallow-water facies sequences in the east, indicating the east to the west retreat of the Neo-Tethys Ocean. The retreat of the Neo-Tethys Ocean in the east was contributed to the earlier tectonic uplift of the eastern Qinghai-Tibet Plateau. The uplift process of the Plateau from the Late Cretaceous to Pliocene is described as follows: During the Late Cretaceous, tectonic uplift of the Qinghai-Tibet Plateau occurred in the northeastern part and the configuration of the Qinghai-Tibet Plateau was characterized by rise in the northeast and depression in the west. In the Paleocene-Eocene interval, the Tengchong-Baingoin and Kuyake-Golmud areas experienced local tectonic uplifting, the West Kunlun uplift zone broadened easterly, the Qilian uplift zone broadened southerly, and the Songpan-Garzê uplift zone shrank easterly. The Oligocene configuration of the Qinghai-Tibet Plateau was characterized by mountain chains rising along its margins and sedimentary basins in the central part because of tectonic uplifts of the Gangdisê and the Himalaya blocks. Meanwhile, the Kunlun-Altyn-Qilian uplift zones have also broadened southerly and northerly. In contrast, the great uplift zones of the Gangdisê, the Himalaya, the Karakorum, and the Kunlun blocks characterize the paleogeographic contours of the Qinghai-Tibet Plateau during the Miocene-Pliocene. Additionally, the thermochronological data on tectonic uplift events in southern Tibet, West Kunlun Mountains, Altyn Ta

关键词： Cenozoic tectonic uplift thermochronology sedimentary records the Qinghai-Tibet Plateau

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Recent advances in glinty appearance rendering

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Computational Visual Media 2022年第4期8卷 535-552页

作者： Junqiu Zhu Sizhe Zhao yanning Xu Xiangxu meng Lu Wang Ling-Qi Yan Shandong University JinanChina University of California Santa BarbaraUSA

The interaction between light and materials is key to physically-based realistic rendering.However,it is also complex to analyze,especially when the materials contain a large number of details and thus exhibit"glinty"visual effects.Recent methods of producing glinty appearance are expected to be important in next-generation computer graphics.We provide here a comprehensive survey on recent glinty appearance rendering.We start with a definition of glinty appearance based on microfacet theory,and then summarize research works in terms of representation and practical rendering.We have implemented typical methods using our unified platform and compare them in terms of visual effects,rendering speed,and memory consumption.Finally,we briefly discuss limitations and future research directions.We hope our analysis,implementations,and comparisons will provide insight for readers hoping to choose suitable methods for applications,or carry out research.

关键词： glinty appearance Monte Carlo methods rendering

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钠离子电池正极材料NaNi_(0.4)Fe_(0.2)Mn_(0.4)O_(2)的制备与储钠性能

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电池工业 2024年第2期28卷 66-71页

作者：王洪波向燕宁孟小吻张志磊河南工学院材料科学与工程学院河南新乡453003

钠离子电池作为可替代锂离子电池的下一代电池,具有独特优势,然而要开发出低成本、良好可逆性和长循环寿命的电极材料仍然存在许多技术难题。本文通过简单的共沉淀法合成Ni_(0.4)^(Ⅱ)Fe_(0.2)^(Ⅱ)Mn_(0.4)^(Ⅱ)(OH)_(2)前驱体,再在空... 详细信息

钠离子电池作为可替代锂离子电池的下一代电池,具有独特优势,然而要开发出低成本、良好可逆性和长循环寿命的电极材料仍然存在许多技术难题。本文通过简单的共沉淀法合成Ni_(0.4)^(Ⅱ)Fe_(0.2)^(Ⅱ)Mn_(0.4)^(Ⅱ)(OH)_(2)前驱体,再在空气气氛下加入碳酸钠进行煅烧,制备得到用于钠离子电池的NaNi_(0.4)Fe_(0.2)Mn_(0.4)O_(2)正极材料。利用X射线衍射(XRD)和扫描电镜(SEM)表征材料的物相结构,结果表明制备的材料是典型的层状斜方六面体结构,部分材料呈现单晶特征。采用恒流充放电的测试方法表征材料的电化学性能。在0.1 C的电流密度下,该材料的初始充电容量可达141.9 mAh/g,放电容量为140.0 mAh/g,首次库仑效率高达98.7%。此外,在0.2 C、0.5 C、1 C、2 C和3 C的倍率下,该材料的放电比容量分别为129.5 mAh/g、112.6 mAh/g、97.8 mAh/g、82.9 mAh/g和72.8 mAh/g,且在0.5 C下循环100圈后的容量保持率约为70.0%,具有良好的倍率性和一定的循环稳定性。

关键词： NaNi_(0.4)Fe_(0.2)Mn_(0.4)O_(2) 钠离子电池共沉淀正极材料过渡金属氧化物

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Synergistic effect of phosphorus doping and MoS_(2) co-catalysts on g-C_(3)N_(4) photocatalysts for enhanced solar water splitting

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Journal of Materials Science & Technology 2023年第27期158卷 171-179页

作者： Xunfu Zhou Pai Wang meng Li Minfu Wu Bei Jin Jin Luo Meifeng Chen Xiaoqin Zhou yanning Zhang Xiaosong Zhou School of Chemistry and Chemical Engineering Key Laboratory of Clean Energy Materials Chemistry of Guangdong Higher Education InstitutesLingnan Normal UniversityZhanjiangGuangdong 524048China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731China Electrochemical NanoEnergy Group School of Chemical Engineering and Light Industry at Guangdong University of TechnologyGuangzhou 510006China Department of Food Science Foshan Polytechnic Foshan 528137China

Carbon nitride(g-C_(3)N_(4))is a promising metal-free and visible-light-responsive photocatalyst.However,its photocatalytic efficiency still suffers from high recombination rates of photoinduced charge carriers,slow kinetics of surface redox reactions,and relatively poor light absorption.Herein,a non-noble metal photocatalyst of MoS_(2) nanodots anchored on P-doped g-C_(3)N_(4) via in situ photodeposition was constructed.With the synergetic effect of the P-doping and MoS_(2) co-catalyst,the as-prepared P-doped g-C_(3)N_(4)/MoS_(2) catalyst has achieved efficient photocatalytic overall water splitting with a hydrogen evolution rate of 121.7μmol h−1 g−1.Experimental results and Density functional theory(DFT)simulations indicate that the enhanced photo-absorption capacity originates from the reduced band gaps by P doping.Meanwhile,the MoS_(2) reduces the overpotential of the water oxidation process and improves hydrogen adsorption capability in the hydrogen evolution reaction.This work can pave a new avenue to design and develop noble-metal-free water-splitting photocatalysts for future large-scale applications.

关键词： Synergistic effect Noble-metal-free photocatalyst P-doping MoS_(2)co-catalyst Water splitting g-C_(3)N_(4)

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