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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo Zhang Yuankang Zha Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie Yin tongfei Shi Haimin Zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental ***,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption *** a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(*** hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(***)under ambient ***,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H *** in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

AN EMBEDDED BOUNDARY METHOD FOR ELLIPTIC AND PARABOLIC PROBLEMS WITH INTERFACES AND APPLICATION TO MULTI-MATERIAL SYSTEMS WITH PHASE TRANSITIONS

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Acta Mathematica Scientia 2010年第2期30卷 499-521页

作者： Shuqiang Wang Roman Samulyak tongfei Guo Department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794 USA Computational Science Center Brookhaven National Laboratory Upton NY 11973 USA

The embedded boundary method for solving elliptic and parabolic problems in geometrically complex domains using Cartesian meshes by Johansen and Colella （1998, J. Comput. Phys. 147, 60） has been extended for elliptic and parabolic problems with interior boundaries or interfaces of discontinuities of material properties or solutions. Second order accuracy is achieved in space and time for both stationary and moving interface problems. The method is conservative for elliptic and parabolic problems with fixed interfaces. Based on this method, a front tracking algorithm for the Stefan problem has been developed. The accuracy of the method is measured through comparison with exact solution to a two-dimensional Stefan problem. The algorithm has been used for the study of melting and solidification problems.

关键词： embedded boundary method elliptic interface problem front tracking Ste-fan problem

基于改进电量法及前推回代法的高渗透率新能源配电网线损计算研究

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河北电力技术 2024年第5期43卷 12-19页

作者：李晓军李铁成崔童飞杨潇杜建桥国网河北省电力有限公司电力科学研究院河北石家庄050021 河北中兴冀能电力发展有限公司科技分公司河北石家庄050021

分布式电源(DG)的高比例接入使得配电网潮流双向流动,传统的线损计算方法不再适用。首先,针对传统电量法电压与功率因数需全网一致假设条件的限制,提出电压电量法和电压功率因数电量法;然后,对多种分布式电源进行节点类型建模,提出改进... 详细信息

分布式电源(DG)的高比例接入使得配电网潮流双向流动,传统的线损计算方法不再适用。首先,针对传统电量法电压与功率因数需全网一致假设条件的限制,提出电压电量法和电压功率因数电量法;然后,对多种分布式电源进行节点类型建模,提出改进前推回代法,实现对高渗透率配电网线损的精细求解;最后,对某地区实际配电线路进行计算,探究各种线损计算方法的误差及适用条件,并通过3种场景对比分析分布式电源接入容量、位置及其他参数对配电网电压以及线损的影响,验证了改进电量法以及改进前推回代法的可行性,对配电网线损计算具有参考意义。

关键词：高渗透率光伏配电网线损计算改进前推回代法电压电量法电压功率因数电量法

A parallel approach to direct resolution of albuterol

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Chinese Science Bulletin 2010年第25期55卷 2814-2816页

作者： ZHONG QingLin PENG XiaoHua WU tongfei FU FangMin cui Xin ZHU Jin DENG JinGen National Engineering Research Center of Chiral Drugs and Key Laboratory of Asymmetric Synthesis & Chirotechnology of Sichuan Province Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China

A library consisting of a series of O,O'-diaryzoyl-L-(-)-tartaric acids (2) was designed and synthesized. The substituent on the aromatic ring of 2 significantly affects the diastereomeric excess and efficiency of the resolution of racemic albuterol (1). Excel-lent resolving reagent 2a was selected for the resolution of rac-1 via the parallel approach. However,a family of three resolving reagents failed to improve the resolution efficiency of rac-1.

关键词：沙丁胺醇并行方式直接解选择试剂 Excel RAC 脂肪酸酒石酸

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食品级丁香酚微乳液相行为及其抑菌性

食品科学技术学报 2024年第3期42卷 104-113页

作者：王一非刘欣悦宋晓秋杨晓波周桐妃金嘉泓叶琳何守魁上海应用技术大学香料香精化妆品学部上海201418 上海交通大学农业与生物学院上海200240

为提高丁香酚的亲水性和抑菌效果,以吐温为表面活性剂,乳酸为助表面活性剂,构建可无限稀释的丁香酚微乳液,并探究微乳化前后丁香酚抑制大肠杆菌和金黄色葡萄球菌的效果。拟三元相图的分析结果表明,与吐温-40和吐温-60相比,吐温-80更能... 详细信息

为提高丁香酚的亲水性和抑菌效果,以吐温为表面活性剂,乳酸为助表面活性剂,构建可无限稀释的丁香酚微乳液,并探究微乳化前后丁香酚抑制大肠杆菌和金黄色葡萄球菌的效果。拟三元相图的分析结果表明,与吐温-40和吐温-60相比,吐温-80更能有效增加微乳液单相区面积;乳酸的增溶效果随着乳酸添加量的增加而提高,当丁香酚与乳酸质量比为1∶3时,丁香酚微乳液单相区面积扩大至78.8%。抑菌特性研究结果显示:在一定范围内,随着吐温-80比例的降低,乳酸比例的增加,丁香酚微乳液的抑菌效果增强;当微乳液组分中丁香酚、乳酸与吐温-80的质量比为1∶3∶6时,质量分数0.05%的丁香酚可完全抑制2种受试细菌的生长,同时,该复合微乳液的抑菌活性显著高于不含乳酸的单一丁香酚微乳。研究开发的微乳液旨在为实现丁香酚的增溶增效提供可行的剂型,并有望用于食品防腐保鲜领域。

关键词：丁香酚乳酸微乳液相行为抑菌效果

根际土壤理化性质及氮磷钾富集影响艾的表型特征与药用品质

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应用与环境生物学报 2024年第4期30卷 767-776页

作者：杨迪宋程威牛童非刘兴巧付国占侯小改河南科技大学农学院洛阳471023

为促进艾的科学栽培管理和种质资源利用,在12个产区收集艾种质资源及根际土壤,测定根际土壤理化性质、叶和茎的氮磷钾含量、表型特征、药用品质,探究指标间的关系,筛选优良种质资源.结果表明:艾的根际土壤变异程度大,均呈中性,氮磷含量... 详细信息

为促进艾的科学栽培管理和种质资源利用,在12个产区收集艾种质资源及根际土壤,测定根际土壤理化性质、叶和茎的氮磷钾含量、表型特征、药用品质,探究指标间的关系,筛选优良种质资源.结果表明:艾的根际土壤变异程度大,均呈中性,氮磷含量丰富,有机碳、速效钾较为缺乏;叶、茎氮磷钾富集的变异系数为19.45%-177.73%,遗传多样性指数为1.526-2.470;表型特征的变异系数为13.14%-36.33%,遗传多样性指数为2.141-2.467;药用品质的变异系数为20.26%-102.13%,遗传多样性指数为2.015-2.477;主成分综合评价表明取自西峡县二郎坪镇(XX-2)、方城县独树镇(FC-1)的种质资源药用品质最优;聚类分析将12份种质资源分为4类,类群Ⅰ、Ⅱ、Ⅲ的叶片产量较高,类群Ⅳ药用品质较高;4个类群间指标的显著性差异分析、相关性分析及回归分析表明叶中的氮、钾素积累量与叶片产量显著正相关,土壤全磷含量与药用品质显著负相关.本研究表明根际土壤理化性质及叶、茎的氮磷钾富集与艾的表型特征、药用品质关系密切,栽培生产中应注意氮磷钾肥的施用配比,磷肥需适量减施,采自西峡县二郎坪镇(XX-2)和方城县独树镇(FC-1)的两份种质资源可作为优良种质开发的备选材料.(图3表9参40)

关键词：艾土壤氮磷钾表型性状药用品质

白垩纪特提斯域原型盆地与岩相古地理及其控油气作用

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石油与天然气地质 2024年第3期45卷 658-672页

作者：黄彤飞张光亚罗贝维喻志骅张磊何治亮白国平尹继全祝厚勤殷进垠姚健欢中国石油勘探开发研究院北京100083 北京大学能源研究院北京100871 中国石油油气和新能源分公司北京100007 中国石油天然气集团有限公司综合管理部北京100007

研究特提斯域在白垩纪的古构造格局、原型盆地及岩相古地理特征,对于深化特提斯域油气富集规律认识具有重要作用。在聚焦早白垩世(125 Ma±)和晚白垩世(90 Ma±)特提斯域原型盆地和岩相古地理发育特征的基础上,重点讨论了白垩纪构造、... 详细信息

研究特提斯域在白垩纪的古构造格局、原型盆地及岩相古地理特征,对于深化特提斯域油气富集规律认识具有重要作用。在聚焦早白垩世(125 Ma±)和晚白垩世(90 Ma±)特提斯域原型盆地和岩相古地理发育特征的基础上,重点讨论了白垩纪构造、沉积演化对特提斯域油气成藏条件及富集的控制作用。研究结果表明:①早白垩世(125 Ma±),新特提洋处于快速张开阶段,在特提斯域近劳亚大陆一侧的欧洲—北非段、中东—中亚段主要发育被动陆缘盆地、裂谷盆地和弧后盆地,在中国西部—印度段主要发育被动陆缘盆地和弧后盆地,中国东部—东南亚段主要发育克拉通内盆地。在特提斯域近冈瓦纳大陆一侧广泛发育被动陆缘盆地。②晚白垩世(90 Ma±),新特提洋处于萎缩早期阶段,特提斯域近冈瓦纳大陆一侧被动陆缘盆地及近劳亚大陆一侧裂谷盆地与弧后盆地继承发展。③特提斯域北缘与南缘在早、晚白垩世均广泛发育厚层以砂岩+泥岩+碳酸盐岩为主的岩相组合,纵向上形成多套有利生-储-盖组合,在冈瓦纳大陆北缘的北非、中东及澳大利亚板块北部地区,油气成藏条件更为优越。④中东波斯湾地区白垩纪在相对稳定的板块构造背景下发育了被动陆缘原型盆地及滨浅海-半深海沉积,加之阿拉伯板块持续位于低纬度环境,由此形成和保存了白垩系富有机质烃源岩和多套优质储-盖组合,为大规模油气富集提供了优越的成藏条件。

关键词：油气富集岩相古地理古构造格局白垩纪原型盆地特提斯域

Action Calcium:an All-or-none Ca^(2+) Transient in Astrocytes

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生物物理学报 2009年第S1期25卷 46-47页

作者： Chen Zhou1,2, tongfei Wang1, Zhen Chai1, Shi-Qiang Wang1 1College of Life Sciences,Peking University, Beijing 100871 2College of Life Sciences, Hebei University, Baoding 071002

While membrane potential is an important mediator delivering information in excitable cells, Ca2+ is a versatile intracellular messenger regulating cell function in almost all eukaryocytes.

关键词： intracellular Ca2+ signal action potential

Photosynthetic response of floating Ulva prolifera to diurnal changes of in-situ environments on the sea surface

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Journal of Oceanology and Limnology 2019年第2期37卷 589-599页

作者： ZHAO Xinyu TANG Xuexi HU Shunxin ZHONG Yi QU tongfei WANG Ying College of Marine Life Sciences Ocean University of China Qingdao 266003 China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China

During yellow sea green tide outbreak, the thalli of Ulva prolifera drifted more than 350 km on the sea surface from off shore of Jiangsu Province to Qingdao city, where they were exposed to complex changes of local environments. The purpose of this study is to investigate the response of the thalli to diurnal changes of environments on the sea surface, and a sea surface environment simulator (SSES) was designed to simulate the natural environment of floating U . prolifera mat. A control experiment is designed in the laboratory, which was processed under suitable conditions (20°C for temperature, 72 μmol photons/(m 2 ·s) for light intensity and 30 for salinity), and an in-situ research was conducted to study the photosynthetic responses of floating U . prolifera to diurnal changes of environments. The results show that the photosynthetic efficiency of the thalli decreased gradually with time, and decreased rapidly after 14:00 local time (LT). After exposed to the environment on the sea surface for 6 h, the photosynthetic activity of the thalli decreased significantly. Furthermore, physiological-level and molecular-level experiments revealed that non-photochemical quenching (NPQ), cyclic electron flow (CEF) and energy redistribution between PSI and PSII all played an important role in the strong photosynthetic plasticity of U . prolifera . NPQ is the most important photoprotective responses to environmental changes before 12:00 LT. The results also confirmed that the CEF and energy redistribution between PSI and PSII are the main synergistic eff ects for the thalli to adapt to the environmental changes when the process NPQ cannot work. And the result can further reveal the reason why U . prolifera can adapt to the living condition of long distance drift on the sea surface. The findings of this research could provide a theoretical basis for explaining outbreaks of the green tide and instructing the management of the problem.

关键词： photosynthetic system floating Ulva prolifera diurnal change photosynthetic plasticity