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Electrocatalytic hydrogen peroxide formation on mesoporous non-metal nitrogen-doped carbon catalyst

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Journal of Energy Chemistry 2016年第2期25卷 249-255页

作者： Frédéric Hasché Mehtap Oezaslan Peter Strasser Tim-Patrick Fellinger Technische Universitat Berlin Department of Chemistry10623 BerlinGermany Max Planck Institut fur Kolloid-und Grenzfliichenforschung Department of Colloids14424 PoadamGermany Carl von Ossietzky University of Oldenburg Department of ChemistryElectrocatalysis26111 OldenburgGermany

Direct electrochemical formation of hydrogen peroxide（H2O2） from pure O2 and H2on cheap metal-free earth abundant catalysts has emerged as the highest atom-efficient and environmentally friendly reaction pathway and is therefore of great interest from an academic and industrial point of view. Very recently,novel metal-free mesoporous nitrogen-doped carbon catalysts have attracted large attention due to the unique reactivity and selectivity for the electrochemical hydrogen peroxide formation [1–3]. In this work,we provide deeper insights into the electrocatalytic activity, selectivity and durability of novel metal-free mesoporous nitrogen-doped carbon catalyst for the peroxide formation with a particular emphasis on the influence of experimental reaction parameters such as p H value and electrode potential for three different electrolytes. We used two independent approaches for the investigation of electrochemical hydrogen peroxide formation, namely rotating ring-disk electrode（RRDE） technique and photometric UV–VIS technique. Our electrochemical and photometric results clearly revealed a considerable peroxide formation activity as well as high catalyst durability for the metal-free nitrogen-doped carbon catalyst material in both acidic as well as neutral medium at the same electrode potential under ambient temperature and pressure. In addition, the obtained electrochemical reactivity and selectivity indicate that the mechanisms for the electrochemical formation and decomposition of peroxide are strongly dependent on the p H value and electrode potential.

关键词： Electrochemical hydrogen peroxide formation Selectivity Mesoporous nitrogen-doped carbon Green synthesis Electrocatalysis Metal-free catalysis

Joint Design of Coalition formation and Semi-Blind Channel Estimation in Fog Radio Access Networks

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China Communications 2019年第11期16卷 1-15页

作者： Zhifeng Wang Feifan Yang Shi Yan Saleemullah Memon Zhongyuan Zhao Chunjing Hu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

Coordinated signal processing can obtain a huge transmission gain for Fog Radio Access Networks(F-RANs).However,integrating into large scale,it will lead to high computation complexity in channel estimation and spectral efficiency loss in transmission performance.Thus,a joint cluster formation and channel estimation scheme is proposed in this paper.Considering research remote radio heads(RRHs)centred serving scheme,a coalition game is formulated in order to maximize the spectral efficiency of cooperative RRHs under the conditions of balancing the data rate and the cost of channel estimation.As the cost influences to the necessary consumption of training length and estimation error.Particularly,an iterative semi-blind channel estimation and symbol detection approach is designed by expectation maximization algorithm,where the channel estimation process is initialized by subspace method with lower pilot length.Finally,the simulation results show that a stable cluster formation is established by our proposed coalition game method and it outperforms compared with full coordinated schemes.

关键词： channel estimation cluster formation game theory fog radio access networks(F-RANs)

First record of contourites from Lower Devonian Lip-trap formation in southeast Australia

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Science China Earth Sciences 2008年第7期51卷 939-946页

作者： G.R.SHI Key Laboratory of Biogeology and Environmental Geology of China Education Ministry Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Typical contourite deposits associated with submarine turbidite fan deposits are recognized for the first time from the Lower Devonian Liptrap formation at Cape Liatrap, Victoria in southeast Australia. The contourites are well integrated within the turbidite fan deposits and are characterized by thin (5-8 cm), lenticular, well-sorted coarse-grained siltstones to fine-grained sandstones with current-ripples and cross beddings. The palaeocurrent directions of the turbidite fan and contourites are perpendicular to each other, with the former directed generally westward while the latter varying from 165° to 190° southward. In view of the facies types and architecture, we suggest that the turbidite fan was developed at the base of a westward inclined palaeo-slope, at the front of which the contourites were deposited as a result of southward flowing deep-sea contour (geostrophic) currents. The depositional setting inter- preted for the Liptrap formation thus may provide a provisional model for the Lower Devonian conti- nental slope and abyssal basin environment in the southeastern part of the Melbourne Trough.

关键词： Contourite turbidite Cape Liptrap Liptrap formation southeast Australia

Development characteristics and controlling factor analysis of the Neogene Minghuazhen formation shallow water delta in Huanghekou area, Bohai offshore basin

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Journal of Palaeogeography 2019年第3期8卷 251-269页

作者： Li-Xin Tian Hao Liu Cheng-Min Niu Xiao-Feng Du Bo Yang Xiao-Dong Lan Dan-Lei Chen Shenzhen Branch of China National Offshore Oil Corporation Shenzhen People's Republic of China School of Ocean Sciences China University of Geosciences (Beijing) Beijing 100083 People's Republic of China Exploration & Exploitation Research Institute Tianjin Branch of China National Offshore Oil Corporation Tianjin People's Republic of China

Based on a combination of high resolution 3-D seismic, drilling and well logging and core data, this study focuses on describing the depositional features of the Neogene Minghuazhen formation shallow water delta in Huanghekou area(HHKA), Bohai offshore basin and discussing the evolution and controlling factors of shallow water delta sandbody. An obvious meandering fluvial delta system developed in sequence 1(SQ1) of the Neogene in HHKA with thinner sandbody of distributary channels and poor development of mouth bar. The sequence texture obviously influences the vertical development and stacking pattern of sandbodies and controls the distribution of sandbodies in plain view as well. In shallow water lacustrine basins, relative topographic height difference leads to change of distribution of accommodation space, and sandbodies of distributary channels usually develop well in local low-lying areas where accommodation space increases. The delta is dominated by distributary channel sandbodies during the early period of base level rising. Sandbodies contact with each other in a lateral stacking pattern and are characterized by a fan shape in plain view. Distributary channels gradually narrow and tend to shift during the mid-late-period of base level rising, while the sandbodies are characterized by a net shape in plain view. During the period of base level slow falling, the multistory/multilateral channel sandbodies dominated the inner front of shallow-water delta and the delta sand dispersal distributes as a lobe shape.

关键词： The Neogene Minghuazhen formation Huanghekou area Bohai offshore basin Shallow water delta Micro-palaeogeomorphology Base level Sandbody stacking pattern

Organic Geochemical and Petrographic Characteristics of the Coal Measure Source Rocks of Pinghu formation in the Xihu Sag of the East China Sea Shelf Basin: Implications for Coal Measure Gas Potential

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 364-375页

作者： WANG Yang QIN Yong YANG Liu LIU Shimin Derek ELSWORTH ZHANG Rui Key Laboratory of Coalbed Methane Resources and Reservoir formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou.Jiangsu 221008China School of Resources and Earth Science.China University of Mining and Technology XuzhouJiangsu 221116China Department of Energy and Mineral Engineering G^3 Center and Energy InstituteThe Pennsylvania State UniversityUniversity Park.PA 16802.USA Jiangsu Design Institute of Geology for Mineral Resources XuzhouJiangsu 221006China Neutron Scattering Division.Oak Ridge National Laboratory Oak RidgeTN 37830USA

Coal measure source rocks, located in the Xihu Sag of the East China Sea Shelf Basin, were analyzed to define the hydrocarbon generation potential, organic geochemistry/petrology characteristics, and coal preservation conditions. The Pinghu source rocks in the Xihu Sag are mainly gas-prone accompany with condensate oil generation. The coals and shales of the Pinghu formation are classified from "fair" to "excellent" source rocks with total organic carbon(TOC) contents ranging from 25.2% to 77.2% and 1.29% to 20.9%, respectively. The coals are richer in TOC and S1+S2 than the shales, indicating that the coals have more generation potential per unit mass. Moreover, the kerogen type of the organic matter consists of types Ⅱ-Ⅲ and Ⅲ, which the maturity Ro ranges from 0.59% to 0.83%. Petrographically, the coals and shales are dominated by vitrinite macerals(69.1%–96.8%) with minor proportions of liptinite(2.5%–17.55%) and inertinite(0.2%–6.2%). The correlation between maceral composition and S1+S2 indicates that the main contributor to the generation potential is vitrinite. Therefore, the coals and shales of the Pinghu formation has good hydrocarbon generation potential, which provided a good foundation for coal measure gas accumulation. Furthermore, coal facies models indicates that the Pinghu coal was deposited in limno-telmatic environment under high water levels, with low tree density(mainly herbaceous) and with low-moderate nutrient supply. Fluctuating water levels and intermittent flooding during the deposition of peat resulted in the inter-layering of coal, shale and sandstone, which potentially providing favorable preservation conditions for coal measure gas.

关键词： hydrocarbon generation potential coal facies coal measure gas Pinghu formation Xihu Sag

Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2 gas field

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Science China Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2, WANG Zecheng1 & XU Dafeng1 1. Research Institute of Petroleum Exploration and Development, Petrochina, Beijing 100083, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Research Institute of Petroleum Exploration and Development Petrochina Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2 gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

The formation and evolution of Chepaizi-Mosuowan paleo-uplift and its control on the distributions of sedimentary facies in the Junggar Basin

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Science China Earth Sciences 2010年第6期53卷 818-831页

作者： JI YouLiang ZHOU Yong KUANG Jun WAN Lu ZHANG Rui LU ChunHong State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China Xinjiang Oil Field Urumqi 834000China

The Chepaizi-Mosuowan paleo-uplift is a large-scale uplift stretching across the Junggar Basin formed during the Yanshanian. It has experienced four evolutionary stages: the initial forming stage (J1), the intense development stage (J2+3), the waning and burial stage (K-E), and the tilting and extinction stage (N-Q). The most intense period of activities is the Middle Jurassic. Dur-ing the Early Jurassic, the Chepaizi-Mosuowan paleo-structure was a low amplitude uplift. Because of the subsequent strong uplifting during Middle-Late Jurassic, the Middle and Upper Jurassic were eroded. With the evolution of the Chepaizi-Mosuowan paleo-uplift, the sedimentary pattern of the basin changed, and the paleo-uplift separated the northern depositional systems from those in the south side. As a result, the basin tectonics controlled the distribution and evolution of the depositional systems. During Early Jurassic, while the paleo-uplift was low, its controlling effect on depositional systems was limited and sediments coming from the northwest could reach the central and southern parts of the basin. With the strong uplifting of the Chepaizi-Mosuowan paleo-structure during Middle-Late Jurassic, sediments from the northwest provenance could only deposit in the northern graben of the paleo-uplift. The intense erosion of the Middle-Upper Jurassic also changed the former sedimentary center of the basin into a source area, supplying sediments for grabens on both sides of the paleo-uplift. In the Cretaceous, regional subsidence caused the paleo-uplift to be buried again and subsequently sediments accumulated on top of it. The depositional facies are dominated by fluvial in the Early Cretaceous and shallow lacustrine to deltaic in the Late Cretaceous. In the history of the long-lasting development of this paleo-uplift, large-scale erosions of the paleohigh not only provided sufficient sediments to the center of the Junggar Basin, but also created favorable conditions for the formation of various subtle traps such as lithologic and st

关键词： Chepaizi-Mosuowan paleo-uplift formation and evolution depositional systems Junggar Basin.

Early diagenetic growth of carbonate concretions in the upper Doushantuo formation in South China and their significance for the assessment of hydrocarbon source rock

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Science China Earth Sciences 2008年第9期51卷 1330-1339页

作者： DONG Jin ZHANG ShiHong JIANG GanQing ZHAO QingLe LI HaiYan SHI XiaoYing LIU JunLai State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesBeijing 100083China Department of Geoscience University of NevadaLas VegasNV 89154-4010USA

Mineralogical and textural characteristics and organic carbon composition of the carbonate concretions from the upper Doushantuo formation (ca. 551 Ma) in the eastern Yangtze Gorge area reveal their early diagenetic (shallow) growth in organic-rich shale. High organic carbon content (up to 10%) and abundance of framboidal pyrites in the hosting shale suggest an anoxic or euxinic depositional environment. Well-preserved cardhouse clay fabrics in the concretions suggest their formation at 0-3 m burial depth, likely associated with microbial decomposition of organic matter and anaerobic oxidation of methane. Gases through decomposition of organic matter and/or from methanogenesis created bubbles and cavities, and anaerobic methane oxidation at the sulfate reduction zone resulted in carbonate precipitation, filling in bubbles and cavities to form spherical structures of the concretions. Rock pyrolysis analyses show that the carbonate concretions have lower total organic carbon (TOC) content but higher effective carbon than those in the host rocks. This may be caused by enclosed organic matter in pores of the concretions so that organic matter was protected from further modification during deep burial and maintained high hydrocarbon generating potential even in over-matured source rock. As a microbialite sensu latu, concretions have special growth conditions and may provide important information on the microbial activities in depositional and early burial environments.

关键词： Doushantuo formation carbonate concretion sedimentary environment hydrocarbon source rock

Dense molecular gas tracers in high mass star formation regions

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Research in Astronomy and Astrophysics 2016年第2期16卷 33-44页

作者： Hong-Jun Ma Yu Gao Jing-Wen Wu Purple Mountain Observatory/Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Department of Physics and Astronomy University of CaliforniaLos AngelesCA 90095USA National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

We report the FCRAO observations that mapped HCN （1-0）, CS （2-1）, HNC （1-0） and HCO＋（1-0） in ten high-mass star forming cores associated with water masers. We present velocity integrated intensity maps of the four lines for these dense cores, compare their line profiles, and derive physical properties of these cores. We find that these four tracers identify areas with similar properties in these massive dense cores, and in most cases, the emissions of HCN and HCO＋ are stronger than those of HNC and CS. We also use the line ratios of HCO＋/HCN, HNC/HCN and HNC/HCO＋ as the diagnostics to explore the environment of these high-mass star forming regions, and find that most of the cores agree with the model that photodominated regions dominate the radiation field, except for W44, for which the radiation field is similar to an X-ray dominated region.

关键词： ISM clouds -- ISM molecules -- stars formation