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高流速离子源辉光放电质谱校正灵敏度因子法定量分析镍基高温合金中痕量稀土及贵金属元素

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分析测试学报 2024年第9期43卷 1317-1323页

作者：屈华阳张馨元胡净宇杨国武王海舟钢铁研究总院北京100081 钢研纳克检测技术股份有限公司北京100081

该文通过全面优化高流速辉光放电离子源分析高温合金痕量元素的仪器条件,系统研究高温合金复杂基体元素造成的质谱干扰,选取稀土元素和贵金属元素分析同位素与合适的质谱分辨率,确立了基于基体匹配的变形高温合金标准物质系列的校正灵... 详细信息

该文通过全面优化高流速辉光放电离子源分析高温合金痕量元素的仪器条件,系统研究高温合金复杂基体元素造成的质谱干扰,选取稀土元素和贵金属元素分析同位素与合适的质谱分辨率,确立了基于基体匹配的变形高温合金标准物质系列的校正灵敏度因子(RSF)定量方案,使测定结果的相对误差由4.0%~80%优化至7.7%~20%,并为痕量分析结果提供了可靠的计量溯源依据。基于此所建立的辉光放电质谱(GDMS)测定镍基高温合金中稀土元素和贵金属元素的方法检出限为0.0010~0.015μg/g,定量下限为0.0030~0.045μg/g。应用于变形高温合金和铸造高温合金实际样品中稀土元素和贵金属元素的分析,测定结果与湿法分析的参考值吻合较好,较好地验证了辉光放电固体样品快捷分析的优势,体现了高分辨质谱检出限低、线性范围宽、可分析元素多的特点,在高温合金材料质控中有着巨大的应用前景。

关键词：辉光放电质谱法镍基高温合金稀土元素贵金属元素校正灵敏度因子

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输水渠系着生藻类多目标水力优化调控研究

节水灌溉 2024年第8期 117-123,130页

作者：胡靖宇管光华杨梦薇吴婷婷吴永妍中国南水北调集团中线有限公司河南分公司郑州450018 武汉大学水资源工程与调度全国重点实验室武汉430072 长江勘测规划设计研究有限责任公司武汉430010

输水渠系正面临着生藻类肆虐的危害,亟需通过水力调控方法剥离边壁的着生藻类,然而大范围的着生藻类脱落将进一步造成渠道水质破坏。为了探究同时满足除藻和水质管理双重目标的最优水力调控模式,研究基于着生藻类水力调控模型,以南方某... 详细信息

输水渠系正面临着生藻类肆虐的危害,亟需通过水力调控方法剥离边壁的着生藻类,然而大范围的着生藻类脱落将进一步造成渠道水质破坏。为了探究同时满足除藻和水质管理双重目标的最优水力调控模式,研究基于着生藻类水力调控模型,以南方某灌区四干渠为仿真实例,运用正交试验和极差分析方法设计不同类型的水力调控方案,对比分析水力调控对边壁着生藻类生物量的剥离效果以及对渠道水质的干扰。研究结果表明,在着生藻类爆发后期用高冲刷流量持续冲刷中等时长的调控模式可极大程度地兼顾藻类调控与水质管理两大需求。实际运用中应结合渠道的着生藻类爆发时段以及流量调度能力,在区间内选择适宜的水力调控组合。

关键词：输水渠系着生藻类水力除藻多目标优化

GraphFlow+:Exploiting Conversation Flow in Conversational Machine Comprehension with Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 272-282页

作者： jing hu Lingfei Wu yu Chen Po hu Mohammed J.Zaki School of Computer Science Central China Normal UniversityWuhan 430079China Pinterest San Francisco 94016USA Meta Mountain View 94039USA Rensselaer Polytechnic Institute Troy 12180USA

The conversation machine comprehension(MC)task aims to answer questions in the multi-turn conversation for a single ***,recent approaches don’t exploit information from historical conversations effectively,which results in some references and ellipsis in the current question cannot be *** addition,these methods do not consider the rich semantic relationships between words when reasoning about the passage *** this paper,we propose a novel model GraphFlow+,which constructs a context graph for each conversation turn and uses a unique recurrent graph neural network(GNN)to model the temporal dependencies between the context graphs of each ***,we exploit three different ways to construct text graphs,including the dynamic graph,static graph,and hybrid graph that combines the *** experiments on CoQA,QuAC and DoQA show that the GraphFlow+model can outperform the state-of-the-art approaches.

关键词： Conversational machine comprehension(MC) reading comprehension question answering graph neural networks(GNNs) natural language processing(NLP)

Pressure Effects on the Magnetic Phase Transition of Mn_(3)SnC_(1−x)N_(x)(x=0,0.5)

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Chinese Physics Letters 2012年第8期29卷 191-193页

作者： hu jing-yu WEN Yong-Chun YAO yuan WANG Cong ZHAO Qing JIN Chang-Qing yu Ri-Cheng Physical College Beijing Institute of TechnologyBeijing 100081 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesP.O.Box 603Beijing 100190 Center for Condensed Matter and Materials Physics Beihang UniversityBeijing 100191

The electronic transport properties of Mn_(3)SnC and Mn_(3)SnC_(0.5)N_(0.5) were measured under pressures up to 1.8 *** ambient pressure,an abrupt increase of resistance occurs around the temperature of magnetic phase transition in both *** transition temperature TC from paramagnetic to ferrimagnetic state decreases linearly at rates of 12.6 and 6.3 K/GPa with pressure for Mn_(3)SnC and Mn_(3)SnC_(0.5)N_(0.5),*** phenomenon could be understood by the Labbe–Jardin tight binding approximation model.

关键词： resistance Transition transition

Synergistically constructed lamination-like network of redox-active polyimide and MXene via π-π interactions for aqueous NH_(4)^(+) storage

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Chinese Journal of Chemical Engineering 2024年第7期71卷 217-224页

作者： jing He Hongye Xuan jing Jin Ke yu Changyao Liyang Lintong hu Minjie Shi Chao Yan School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Jiangsu New Yangzi Shipbuilding Co. LtdJingjiang 214532China

As a nonmetallic charge carrier,ammonium ion(NH_(4)^(+))has garnered significant attention in the construction of aqueous batteries due to its advantages of low molar mass,small hydration size and rapid diffusion in aqueous *** are a kind of potential electro-active materials for aqueous NH_(4)^(+)***,traditional polymer electrodes are typically created by covering the bulky collectors with excessive additives,which could lead to low volume capacity and unsatisfactory ***,a nanoparticle-like polyimide(PI)was synthesized and then combined with MXene nanosheets to synergistically construct an additive-free and self-standing PI@MXene composite ***,the redox-active PI nanoparticles are enclosed between conductive MXene flakes to create a 3D lamination-like network that promotes electron transmission,while theπ-πinteractions existing between PI and MXene contribute to the enhanced structural integrity and stability within the composite *** such,it delivers superior aqueous NH_(4)^(+)storage behaviors in terms of a notable specific capacity of 110.7 mA·h·cm^(–3) and a long lifespan with only 0.0064%drop each ***,in-situ Raman and UV–Vis examinations provide evidence of reversible and stable redox mechanism of the PI@MXene composite electrode during NH_(4)^(+)uptake/removal,highlighting its significance in the area of electrochemical energy storage.

关键词： Synergetic coupling Composite materials Polyimide Energy storage Aqueous ammonium ion batteries

Mo@PANI-catalyzed oxidative deoximation reaction

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Chinese Chemical Letters 2024年第2期35卷 407-410页

作者： Yiyang Zhang Wen Li Zuofeng hu Xiaobi jing Lei yu School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Yangzhou Yangzi Auto Interior & Exterior Co. Ltd.Yangzhou 225119China

Deoximation is an important transformation in synthetic *** can be employed in protection,characterization and purification of the carbonyls,and in the synthesis of ketones from non-carbonyl *** the field,oxidative deoximation reaction can utilize the driving force caused by the oxidation process so that the reaction can occur under relatively mild ***,we designed and prepared polyaniline-supported molybdenum(Mo@PANI)just by immersing PANI into the EtOH/H_(2)O solution of MoCl_(5).The material was successfully applied as the efficient catalyst for oxidative deoximation reactions,which were performed in ethanol using H_(2)O_(2)as the clean *** substrate scope of the reaction was *** could be applied on heterocycle-containing substrates,making this protocol preferable for pharmaceutical intermediate *** Mo is a necessary trace element for both animals and plants,this method is environment-friendly and is suitable for large-scale *** work as the first example of Mo-catalyzed oxidative deoximation reaction may inspire novel ideas for both catalyst design and synthetic process development.

关键词： Molybdenum Polyaniline Oxidation Deoximation Carbonyl

Dual-objective two-photon microscope for volumetric imaging of dense scattering biological samples by bidirectional excitation and collection

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Photonics Research 2024年第6期12卷 1351-1361页

作者： MUyuE ZHAI jing yu YANhuI hu HANG yu BEICHEN XIE YI yu DAWEI LI AIMIN WANG HEPING CHENG National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Research Unit of Mitochondria in Brain Diseases Chinese Academy of Medical SciencesPKU-Nanjing Institute of Translational MedicineNanjing 211500China Beijing Transcend Vivoscope Biotech Beijing 100085China College of Engineering Peking UniversityBeijing 100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China Center for Quantitative Biology Peking UniversityBeijing 100871China School of Electronics Peking UniversityBeijing 100871China State Key Laboratory of Advanced Optical Communication System and Networks Peking UniversityBeijing 100871China

Full view observation throughout entire specimens over a prolonged period is crucial when exploring the physiological functions and system-level ***-photon microscopy(MPM)has been widely employed for such purposes owing to its deep penetration ***,the current MPM struggles with balancing the imaging depth and quality while avoiding photodamage for the exponential increasement of excitation power with the imaging ***,we present a dual-objective two-photon microscope(Duo-2P),characterized by bidirectional two-photon excitation and fluorescence collection,for long-duration volumetric imaging of dense scattering ***-2P effectively doubles the imaging depth,reduces the total excitation energy by an order of magnitude for samples with a thickness five times the scattering length,and enhances the signal-to-noise ratio up to 1.4 *** these advantages,we acquired volumetric images of a 380-μm suprachiasmatic nucleus slice for continuous 4-h recording at a rate of 1.67 s/volume,visualized the calcium activities over 4000 neurons,and uncovered their state-switching *** conclude that Duo-2P provides an elegant and powerful means to overcome the fundamental depth limit while mitigating photodamages for deep tissue volumetric imaging.

关键词： excitation overcome exponential

High-chromium vanadium-titanium magnetite all-pellet integrated burden optimization and softening-melting behavior based on flux pellets

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 498-507页

作者： Bojian Chen Tao Jiang jing Wen Guangdong Yang Tangxia yu Fengxiang Zhu Peng hu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China State key laboratory of vanadium and titanium resources comprehensive utilization Panzhihua 617000China

High-chromium vanadium-titanium magnetite(HVTM)is a crucial polymetallic-associated resource to be *** allpellet operation is a blast furnace trend that aims to reduce carbon dioxide emissions in the *** referencing the production data of vanadium-titanium magnetite blast furnaces,this study explored the softening-melting behavior of high-chromium vanadium-titanium magnetite and obtained the optimal integrated burden based on flux *** results show that the burden with a composition of 70wt%flux pellets and 30wt%acid pellets exhibits the best softening-melting *** comparison to that of the single burden,the softening-melting characteristic temperature of this burden composition was *** melting interval first increased from 307 to 362℃and then decreased to 282℃.The maximum pressure drop(ΔPmax)decreased from 26.76 to 19.01 *** permeability index(S)dropped from 4643.5 to 2446.8 kPa·℃.The softening-melting properties of the integrated burden were apparently *** acid pellets played a role in withstanding load during the softening *** flux pellets in the integrated burden exhibited a higher slag melting point,which increased the melting temperature during the melting *** slag homogeneity and the TiC produced by over-reduction led to the gas permeability deterioration of the single *** segregation of the flux and acid pellets in the HVTM proportion and basicity mainly led to the better softening-melting properties of the integrated burden.

关键词： high-chromium vanadium-titanium magnetite softening-melting properties all pellets integrated burden flux pellets

Effects of Ta content on microstructure and oxidation behavior of AlCoCrFeNiYTax high entropy alloy

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Rare Metals 2024年第9期43卷 4462-4475页

作者： Cang Gu Jun-Hao hu Jian-Bo Song Cheng Xu Ming-yu hu yu-Xuan Zhang Jiang Tian Chao Li jing Feng Faculty of Materials Science and Engineering Kunming University of Science and Technology Department of Physics Hong Kong Baptist University

The oxidation behavior of the Al Co Cr Fe Ni YTaxhigh entropy alloy（HEA） doped with different Ta contents at 1100 °C is investigated. In this study, different reasons for the spallation of the oxide scales of HEAs without/with excessive Ta addition after 1000 h of oxidation are discussed, and the most suitable Ta doping content for this HEA is explored, in which the HEA exhibits both an exceptionally low oxidation rate, and the formation of oxide scales composed of intact a-Al2O3. Meanwhile, it is found that the addition of Ta can effectively inhibit the phase transition of β phase, which makes the surface of the oxide scale smoother. By combining our experimental results with Wagner–Hauffe theory, the influence of Ta drag effect on oxide scale growth is explained, which provides some theoretical guidance for the subsequent design of Al Co Cr Fe Ni HEAs, and can lead to the development of thermal barrier coatings at higher service temperature.

关键词： Al2O3 scales Elements diffusion High-entropy alloy Oxidation