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利用卫星测高、GRACE 和 GOCE 资料估计全球海洋表面地转流

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海洋学报 2014年第9期36卷 45-55页

作者：冯贵平金双根 jose m.sanchez Reales 上海海洋大学海洋科学学院上海201306 中国科学院上海天文台上海200030 University of Alicante AlicanteSpain

重力恢复和气候试验 GRACE（gravity recovery and climate experiment）卫星极大地提高了地球重力场的精度和分辨率，特别是中长波分量，联合卫星测高数据可获得全球海洋表面大尺度洋流循环。另外，新一代地球重力和海洋环流探测卫星 G... 详细信息

重力恢复和气候试验 GRACE（gravity recovery and climate experiment）卫星极大地提高了地球重力场的精度和分辨率，特别是中长波分量，联合卫星测高数据可获得全球海洋表面大尺度洋流循环。另外，新一代地球重力和海洋环流探测卫星 GOCE（gravity field and steady-state ocean circulation explorer）于2009年3月成功发射，采用卫星重力梯度测量原理，对重力场的高频部分非常敏感，使其高分辨率监测全球海洋循环成为可能。本文利用1～7年 GRACE 观测数据确定的重力场模型和18个月 GOCE 观测数据确定的地球重力场模型 GO CONS GCF 2 TIm R3，联合卫星测高确定的平均海面高模型 mSS CNES CLS 11，分别估计全球海洋表面地转流，并且与实测浮标数据结果进行比较。分析表明 GOCE 重力卫星确定的重力场模型具有更高的空间分辨率，能够确定高精度和高空间分辨率的全球海洋地转流，如墨西哥湾暖流的细节和特征，并且与实测浮标结果基本一致。而基于1～4年 GRACE 观测资料的模型不能很好估计全球地转流特征，基于7年 GRACE 观测资料的重力场模型 ITG-Grace2010s 确定的全球地转流的精度仍低于18个月 GOCE 观测数据确定的地球重力场模型 GO CONS GCF 2 TIm R3的结果，估计的全球地转流仍含有较大的噪声，不能很好地反应中小尺度地转流细节特征。并计算 ITG Grace2010s 和 GOCE TIm3的稳态海面地形和全球平均地转流的内符合精度，结果显示，在全球范围内，GOCE TIm3的稳态海面地形和全球平均地转流的精度都比 ITG Grace2010s 结果的精度有着很大的改善，其中 ITG Grace2010s 的稳态海面地形的精度为21．6 cm，而 GOCE TIm3的结果则为7．45 cm，ITG Grace2010s 的全球平均地转流的精度为40．7 cm/s，而 GOCE TIm3的结果则为19．6 cm/s。

关键词：地转流卫星测高

Ammonia Sensing System Based on Wavelength modulation Spectroscopy

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Photonic Sensors 2015年第2期5卷 109-115页

作者： Duarte VIVEIROS Joao FERREIRA Susana O. SILVA Joana RIBEIRO Deolinda FLORES jose L. SANTOS Orlando FRAZAO jose m. BAPTISTA INESC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Geology Center of the University of Porto and Department of Geosciences Environment and Spatial Plannings Facultyof Science at University of Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Department of Physics and Astronomy Faculty of Science at University of Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Competence Center of Exact Sciences and Engineering University of Madeira Campus da Penteada 9000-390 Funchal Portugal

A sensing system in the near infrared region has been developed for ammonia sensing based on the wavelength modulation spectroscopy （WmS） principle. The WmS is a rather sensitive technique for detecting atomic/molecular species, presenting the advantage that it can be used in the near-infrared region by using the optical telecommunications technology. In this technique, the laser wavelength and intensity were modulated by applying a sine wave signal through the injection current, which allowed the shift of the detection bandwidth to higher frequencies where laser intensity noise was typically lower. Two multi-pass cells based on free space light propagation with 160 cm and 16 cm of optical path length were used, allowing the redundancy operation and technology validation. This system used a diode laser with an emission wavelength at 1512.21nm, where NH3 has a strong absorption line. The control of the NH3 gas sensing system, as well as acquisition, processing and data presentation was performed.

关键词： Ammonia sensing fiber optic system near infrared region wavelength modulation spectroscopy,environment

Understanding the catalysis of chromium trioxide added magnesium hydride for hydrogen storage and Li ion battery applications

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Journal of magnesium and Alloys 2024年第3期12卷 1117-1130页

作者： D.Pukazhselvan IhsanÇaha Catarina de Lemos Sergey m.mikhalev Francis Leonard Deepak Duncan Paul Fagg Department of mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal Nanostructured materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This study explores how the chemical interaction between magnesium hydride(mgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of mgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of mgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added mgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with mgH_(2).In depth characterization study by X-ray diffraction(XRD)technique provides convincing evidence that the CrO_(3) additive interacts with mgH_(2) and produces Cr/mgO *** free energy analyses confirm the thermodynamic feasibility of conversion from mgH_(2)/CrO_(3) to mgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEm)and energy dispersive spectroscopy(EDS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of mgO rock salt *** is also convincing ground to consider that mgO rock salt accommodates Cr in the *** observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of mgH_(2),both for the improved storage of hydrogen and lithium.

关键词： Hydrogen storage Rechargeable batteries Binary hydrides metal oxides Catalytic mechanism.

High-repetition-rate source of nanosecond duration kA-current pulses driven by relativistic laser pulses

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High Power Laser Science and Engineering 2024年第3期 111-120页

作者： michael Ehret Jakub Cikhardt Philip Wykeham Bradford Iuliana-mariana Vladisavlevici Tomas Burian Diego de Luis jose Luis Henares Rubén Hernández martín Jon Imanol Api?aniz Roberto Lera JoséAntonio Pérez-Hernández Jo?o Jorge Santos Giancarlo Gatti Centro de Láseres Pulsados (CLPU) Czech Technical University in Prague Faculty of Electrical Engineering Univ. Bordeaux-CNRS-CEA Centre Lasers Intenses et Applications (CELIA) Department of Radiation and Chemical Physics FZU-Institute of Physics of the Czech Academy of Sciences Univ. Bordeaux-CNRS-CEA Centre Lasers Intenses et Applications (CELIA)

We report the first high-repetition-rate generation and simultaneous characterization of nanosecond-scale return currents of kA-magnitude issued by the polarization of a target irradiated with a PW-class high-repetition-rate titanium:sapphire laser system at relativistic *** present experimental results obtained with the VEGA-3 laser at intensities from5×1018to 1.3×1020W cm-2.A non-invasive inductive return-current monitor is adopted to measure the derivative of return currents of the order of kA ns-1and analysis methodology is developed to derive return *** compare the current for copper,aluminium and Kapton targets at different laser *** data show the stable production of current peaks and clear prospects for the tailoring of the pulse shape,which is promising for future applications in highenergy-density science,for example,electromagnetic interference stress tests,high-voltage pulse response measurements and charged particle beam *** compare the target discharge of the order of hundreds of nC with theoretical predictions and a good agreement is found.

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Characterization of a 3-Phase a.c. Free Burning Arc Plasma

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Plasma Science and Technology 2006年第2期8卷 156-163页

作者：夏维东 Laurent FULCHERI jose GONZALEZ-AGUILAR 李辉 Thomas m. GRUENBERGER University of Science" and Technology of China Hefei 230027 China. Centre for Energy Studies Ecole des Mines de Paris Rue Claude Daunesse F-06904 Sophia Antipolis France University of Science and Technology of China Hefei 230027 China.

A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are ＂burning＂ freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system.

关键词： 3-phase AC arc plasma free arc arc motion arc commutating arc instabilities

XAANTAL2 （AGL14） Is an Important Component of the Complex Gene Regulatory Network that Underlies Arabidopsis Shoot Apical meristem Transitions

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molecular Plant 2015年第5期8卷 796-813页

作者： Rigoberto V. Perez-R.u.iz Berenice Garcia-Ponce Nayelli marsch-martinez Yamel Ugartechea-Chirino mitzi Villajuana-Bonequi Stefan de Folter Eugenio Azpeitia jose Davila-Velderrain David Cruz-sanchez Adriana Garay-Arroyo maria de la Paz sanchez Juan m. Estevez-Palmas Elena R. Alvarez-Buylla Instituto de Ecologia Universidad Nacionat Autonoma de Moxico 3er Circuito Exterior s/no Junto al Jardin Bot~nico and Centro de Ciencias de la ComplejidadCiudad Universitaria Coyoacan 04510 Mexico D.F. Mexico Laboratorio Nacional de Genemica para la Biodiversidad (Langebio) Centro de Investigaci6n y de Estudios Avanzados del Instituto Polit~cnico Nacional(CINVESTAV-IPN) Km. 9.6 Carretera Irapuato - Leen AP 629 36821 Irapuato Guanajuato Mexico University of California 431 Koshland Hall Berkeley CA 94720 USA These authors contributed equally to this article. present address: Departamento de Biotecnologia y Biquimica Centro de )nvestigaci6n y de Estudios Avanzados del Instituto Polit6cnico Nacional(CINVESTAV-IPN) Km. 9.6 Libramiento Norte Carr. Irapuato-Leen 36821 Irapuato Guanajuato Mexico present address: max Planck Institute for Plant Breeding Research D-50829 Cologne Germany Present address: INRIA Project-Team Virtual Plants/CIRAD/INRA UMR AGAP Campus St Priest - BAT 5 CC 05018 860 rue de St Priest 34095 Montpellier Cedex5 France

In Arabidopsis thaliana, multiple genes involved in shoot apical meristem （SAm） transitions have been char- acterized, but the mechanisms required for the dynamic attainment of vegetative, inflorescence, and floral meristem （Vm, Im, Fm） cell fates during SAm transitions are not well understood. Here we show that a mADS-box gene, XAANTAL2 （XAL2/AGL14）, is necessary and sufficient to induce flowering, and its regula- tion is important in Fm maintenance and determinacy, xal2 mutants are late flowering, particularly under short-day （SD） condition, while XAL2 overexpressing plants are early flowering, but their flowers have vege- tative traits. Interestingly, inflorescences of the latter plants have higher expression levels of LFY, AP1, and TFL1 than wild-type plants. In addition we found that XAL2 is able to bind the TFL1 regulatory regions. On the other hand, the basipetal carpels of the 35S：：XAL2 lines lose determinacy and maintain high levels of WUS expression under SD condition. To provide a mechanistic explanation for the complex roles of XAL2 in SAm transitions and the apparently paradoxical phenotypes of XAL2 and other mADS-box （SOCl, AGL24） over- expressors, we conducted dynamic gene regulatory network （GRN） and epigenetic landscape modeling. We uncovered a GRN module that underlies Vm, Im, and Fm gene configurations and transition patterns in wild- type plants as well as loss and gain of function lines characterized here and previously. Our approach thus provides a novel mechanistic framework for understanding the complex basis of SAm development.

关键词： XAL2/AGL14 mADS-box TFL1 SAm transitions floral reversion gene regulatory networks,epigenetic landscape modeling

Disturbance and forest recovery in the monarch Butterfly Biosphere Reserve,mexico

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Journal of Forestry Research 2020年第5期31卷 1551-1566页

作者： jose Lopez-Garcıa Rafael m.Navarro-Cerrillo Instituto de Geografıa Universidad Nacional Autonoma de MexicoCiudad UniversitariaC.P.04510 CoyoacanDFMexico Departamento de Ingenierıa Forestal Universidad de CordobaCampus de RabanalesCarretera Nacional IV km 39614014 CordobaSpain

Analysis of the change in forest cover is important to determine stand dynamics and the processes involved in disturbance and *** of the core zone of the monarch Butterfly Biosphere Reserve were studied using photo interpretation techniques,considering biennial changes between 1999 and 2013 and changes over the whole period of study 1999–*** matrices were elaborated to determine the processes of change involved in both recovery and *** biennial changes for the whole period amounted to 2274 ha;343 ha accounted as degraded in more than one biennial *** total changes in forest cover between 1999 and 2013 involved 4902 ha,out of which,2912 ha were affected by disturbance,and 1990 ha were *** density and 2013 vegetation cover maps,the overall accuracy was 95.6%and 90.2%,*** combining both maps,gradual processes were revealed that were not evident in separate *** methodology is useful for the management and conservation of natural protected areas.

关键词： Illegal logging Forest density change Forest recovery Conifer forests monarch Butterfly Biosphere Reserve

Geodesic Vulnerability Approach for Identification of Critical Buses in Power Systems

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Journal of modern Power Systems and Clean Energy 2021年第1期9卷 37-45页

作者： Jesus Beyza Eduardo Garcia-Paricio Hector F.Ruiz jose m.Yusta Instituto Tecnologico de morelia Avenida Tecnologico 1500Lomas de Santiaguito58120Mexico the Department of Electrical Engineering University of ZaragozaC/Maria de Luna 350018Spain

One of the most critical issues in the evaluation of power systems is the identification of critical buses. For this purpose, this paper proposes a new methodology that evaluates the substitution of the power flow technique by the geodesic vulnerability index to identify critical nodes in power *** methods are applied comparatively to demonstrate the scope of the proposed approach. The applicability of the methodology is illustrated using the IEEE 118-bus test system as a case study. To identify the critical components, a node is initially disconnected, and the performance of the resulting topology is evaluated in the face of simulations for multiple cascading faults. Cascading events are simulated by randomly removing assets on a system that continually changes its structure with the elimination of each component. Thus, the classification of the critical nodes is determined by evaluating the resulting performance of 118 different topologies and calculating the damaged area for each of the disintegration curves of cascading failures. In summary, the feasibility and suitability of complex network theory are justified to identify critical nodes in power systems.

关键词： Power system critical node complex network theory cascading failure load flow

Reflux-synthesized bulk and diluted W-Nb-O mixed oxide bronzes for the valorization of short-chain oxygenates aqueous mixtures

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Chinese Journal of Catalysis 2019年第11期40卷 1778-1787页

作者： D.Delgado A.Fernández-Arroyo N.La Salvia m.E.Domine jose m.López Nieto Instituto de Tecnología Química Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas Avenida de los Naranjos s/n 46022 Valencia Spain

This work reports the preparation of bulk and KIT-6-diluted W-Nb-O mixed oxide bronzes by a reflux method. The influence of the incorporation of Nb and a mesoporous silica on the physicochemical features of the catalysts is studied. The addition of Nb favors the formation of single-phase oxide bronze structure, with improved Lewis acidity;while the incorporation of KIT-6 gives rise to well-dispersed mixed metal oxide particles on the diluter. These diluted W-Nb-O catalysts present enhanced surface areas and mesopore volumes. The materials have been tested in the valorization of an aqueous model mixture (acetol/propanal/ethanol/acetic acid/water weight ratio of 5/25/10/30/30), through C-C bond formation reactions. The increase in the Lewis nature of surface acid sites stands as the key point to maximize the total organic yield during the reaction (C5-C10 products). The best catalysts maintain their catalytic behavior after five consecutive uses.

关键词： KIT-6 W-Nb-O oxides Aqueous oxygenates Biomass feedstocks C-C bond formation