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Selective oxidation using in-situ generated hydrogen peroxide over titanosilicates

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Chinese Journal of Structural Chemistry 2024年第6期43卷 12-14页

作者： Zhipeng Wan Hao Xu Peng Wu state key laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China Institute of Eco-Chongming Shanghai202162China

Titanosilicates are a class of heteroatom-containing zeolitic materials with tetrahedrally coordinated Ti^(4+)ions incorporated into crystalline zeolite frameworks,with TS-1,Ti-MWW and Ti-MOR as representative and attractive selective oxidation *** liquid-phase oxidations of a variety of substrates such as olefins and ketones with the green oxidant of H_(2)O_(2)over titanosilicates under mild conditions have attracted considerable research interests in the clean production of fine and bulk chemicals,among which propylene epoxidation and cyclohexanone ammoximation have been industrialized[1].

关键词： silicate zeolite propylene

An alternative 2D ICEEMDAN-based denoising method and its application in processing magnetic anomaly data

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Geodesy and Geodynamics 2024年第5期15卷 465-476页

作者： Jun Xu Jinsong Du Changqing Yuan School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Hubei Subsurface Multi-scale Imaging key laboratory China University of GeosciencesWuhan 430074China state key laboratory of Geological processes and Mineral Resources China University of GeosciencesWuhan 430074China key laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China

Due to environmental noise and human factors,magnetic data collected in the field often contain various noises and interferences that significantly affect the subsequent data processing and *** Mode Decomposition(EMD),an adaptive multiscale analysis method for nonlinear and non-stationary signals,is widely used in geophysical and geodetic data *** with traditional EMD,Improved Complete Ensemble EMD with Adaptive Noise(ICEEMDAN)is more effective in addressing the problem of mode *** on the principles of 1D ICEEMDAN,this paper presents an alternative algorithm for 2D ICEEMDAN,extending its application to two-dimensional *** effectiveness of the proposed approach is demonstrated through synthetic signal experiments,which show that the 2D ICEEMDAN exhibits a weaker mode mixing effect compared to the traditional bidimensional EMD(BEMD)***,to improve the performance of the denoising method based on 2D ICEEMDAN and preserve useful signals in high-frequency components,an improved soft thresholding technique is *** magnetic anomaly data testing indicates that our denoising method effectively preserves signal continuity and outperforms traditional soft thresholding *** validate the practical application of this improved threshold denoising method based on 2D ICEEMDAN,it is applied to ground magnetic survey data in the Yandun area of *** results demonstrate the effectiveness of the method in removing noise while retaining essential information from practical magnetic anomaly *** particular,practical applications suggest that 2D ICEEMDAN can extract trend signals more accurately than the *** conclusion,as a potential tool for multi-scale decomposition,the 2D ICEEMDAN is versatile in processing and analyzing 2D geophysical and geodetic data.

关键词： 2D ICEEMDAN Mode mixing effect Magnetic anomaly Denoising Improved soft thresholding

The interannual periodicity of precipitation and its links to the large-scale circulations over the Third Pole

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Journal of Geographical Sciences 2024年第8期34卷 1457-1471页

作者： LIANG Liqiao LIU Qiang LI Jiuyi state key laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchCASBeijing 100101China state key laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China key laboratory for Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China key laboratory of Water Cycle and Related Land Surface processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

To understand the spatio-temporal variability of precipitation(P)in the Third Pole region(centered on the Tibetan Plateau-TP),it is necessary to quantify the interannual periodicity of P and its relationship with large-scale *** this study,Morlet wavelet transform was used to detect significant(p<0.05)periodic characteristics in P data from meteorological stations in four climate domains in the Third Pole,and to reveal the major large-scale circulations that triggered the variability of periodic P,in addition to bringing large amounts of water *** wavelet transform results were as follows.(1)Significant quasiperiodicity varied from 2 to 11 *** high-frequency variability mode(2 to 6 years quasi-periods)was universal,and the low-frequency variability mode(7 to 11 years quasi-periods)was rare,occurring mainly in the westerlies and Indian monsoon domains.(2)The majority of periods were base periods(53%),followed by two-base *** all stations in the Third Pole(95%)showed one or two periods.(3)Periodicity was widely detected in the majority of years(84%).(4)The power spectra of P in the four domains were dominated by statistically significant high-frequency oscillations(ie.,with short periodicity).(5)Large-scale circulations directly and indirectly influenced the periodic P variability in the different *** mode of P variability in the different domains was influenced by interactions between large-scale circulation features and not only by the dominant circulation and its control of water vapour *** results of this study will contribute to better understanding of the causal mechanisms associated with P variability,which is important for hydrological science and waterresourcemanagement.

关键词： precipitation interannual periodicity Morlet wavelet large-scale circulations Third Pole

Ore Geology,H-O-C Isotopes and 40Ar-39Ar Dating of the Wutonggou Iron Deposit,Eastern Tianshan,NW China:Implications for the Source,Timing,and Genesis of Hydrothermal Mineralization in a Sedimentary Iron Deposit

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Journal of Earth Science 2024年第4期35卷 1170-1185页

作者： Chun-Long Wang Yi-Tian Wang state key laboratory of Geological processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourcesChina University of GeosciencesWuhan430074China MNR key laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing100037China

The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern Tianshan,NW China,and has been regarded as a sedimentary iron *** hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits,previous studies mainly focused on sedimentary-related iron mineralization,while the nature and contribution of hydrothermal fluids are poorly ***,an integrated study of ore geology,H-O-C isotopes and^(40)Ar-^(39)Ar dating,is conducted on the Wutonggou deposit,in order to reveal the features,source,and timing of hydrothermal *** studied deposit includes two mining sections namely the Jianshan and ***δ^(18)O values of early magnetite from the Jianshan section range from+3.0‰to+5.8‰that nearly consistent with classic magmatic magnetite,while increase to 6.3‰-8.0‰in the late *** from the two sections shows comparable H-O isotopic compositions and identical fractionation trends,and is plotted in or periphery to the primary magmatic water *** from the two sections are broadly similar in carbon and oxygen isotopic compositions,and siderite from the Wutonggou section is plotted in the same ***,comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining ***,water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections,and caused the isotopic fractionation in late *** extracted from a hydrothermal siderite ore yielded a^(40)Ar-^(39)Ar plateau age of 299.5±2.0 Ma,indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity *** together,the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores,a

关键词： iron deposits H-O-C isotopes 40Ar-39Ar dating sedimentary iron deposits Wutonggou iron deposit eastern Tianshan

Taphonomy and Paleoecology of Lycoptera: A Case Study from the Lower Jehol Group in Western Liaoning, Northeastern China

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Journal of Earth Science 2024年第3期35卷 737-746页

作者： Zhongwu Lan Rong Cao Shujing Zhang state key laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China state key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China state key laboratory of Geological processes and Mineral Resources China University of GeosciencesWuhan 430078China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geology Trinity CollegeDublin 999015Ireland

Taphonomy and paleoecology(biological behavior)of the Early Cretaceous fish fossils are poorly *** study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province,NE *** XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing *** may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic ***μ-XRF imaging analysis shows a dominant chemical composition of Al,Si,P,S,Rh,K,Ca,Ti,C,Cr,Mn,Fe,Ni,among which P,Ca,C and S are enriched in the fish skeleton in comparison to the *** suggests a dominant apatite composition for the fish *** influence did not smear off these organic signals probably because of protection of *** coexistance of C and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas *** head of juvenile fish stays close to the body of adult *** further discoveries,such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by *** acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of *** adult Lycoptera protected their juveniles by its body at the moment before *** biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.

关键词： Lycoptera taphonomy paleoecology fish Jehol Group NE China.

Micro-flow structure at regime transition from bubbling to turbulent fluidization in a fluidized bed

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Particuology 2024年第6期89卷 117-130页

作者： Chaoyu Yan Yue Yuan Xiaoyang Wei Jesse Zhu state key laboratory of Heavy Oil Processing Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China China Beacons Institute The University of NottinghamNingbo315100China Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity *** fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical *** the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent ***,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent *** transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom *** wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency *** sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized *** micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale *** work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.

关键词： Flow regime transition Bubbling fluidization Turbulent fluidization Micro-flow structure Differential pressure fluctuation

Prospects of sediment deposition at small watershed scale in the black soil region of Northeast China: A mini review

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Pedosphere 2024年第1期34卷 30-35页

作者： Guanghui ZHANG Yang YANG Yingna LIU Zhiqiang WANG state key laboratory of Earth Surface processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Sediment deposition is one of the most significant processes in small watersheds characterized by gentle long hillslopes in the black soil(Mollisol)region of Northeast China, as indicated by severe ephemeral gully and gully erosion on hillslopes and very low sediment concentrations in river *** reviews have been conducted to summarize the related research in this region. The objectives of this review were to identify the potential factors influencing sediment deposition, review related studies, and propose future research needs in the black soil region of Northeast China. Sediment deposition is controlled by the deficit between sediment transport capacity of flow and sediment load. Hence, all factors affecting flow transport capacity and sediment load directly affect sediment deposition. For a specific small watershed, the change in slope gradient along the flow path is the key factor affecting sediment deposition. Shelterbelts, ridge tillage systems, terraces, grass strips, road distribution, ponds and reservoirs, and land-use patterns also influence the spatial distribution and rate of deposition. The trace method has been widely used to quantify sediment deposition in this region. The results of cesium-137(^(137)Cs),lead-210(^(210)Pb), and magnetic susceptibility reveal that serious deposition occurs on the back and foot slopes. Distinct deposition occurs in front of contour shelterbelts. Future studies should focus on the methodology, spatial and temporal variations, dominant influencing factors and their mechanisms, and the potential effects on land productivity within specific small watersheds and across the black soil region. This review provides insights into the sediment deposition process in small watersheds characterized by gentle, long hillslopes.

关键词： Mollisol sedimentation soil and water conservation soil erosion soil redistribution

Corrosion behavior of Al_(2)O_(3)-C bricks in MnO-containing mold slag

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Journal of Iron and Steel Research International 2024年第6期31卷 1486-1492页

作者： Yi-jiang Zhao Guang-qiang Li Yang Wu Cheng Yuan Ze Meng Xiao-xuan Deng Yu Liu The state key laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina key laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial key laboratory for New processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Research Institute of Technology Shougang Group Co.Ltd.Beijing 100043China

In order to explore the corrosion mechanism of Al_(2)O_(3)-C refractories in the mold flux bearing MnO,the immersion test of Al_(2)O_(3)-C refractories in CaO-SiO2-CaF2-MnO slag with different MnO contents was carried out at 1550℃.The results show that Mn particles were observed in the slag after experiment,due to the reduction of MnO by graphite in *** amounts of graphite were observed at the interface between refractories and slag,indicating that the oxidation of graphite is limited by the poor contact between graphite and molten ***,the oxidation of graphite is not the main cause of damage to refractories.A small quantity of CaO·2Al_(2)O_(3)(CA_(2))and CaO·6Al_(2)O_(3)(CA_(6))adjacent to Al_(2)O_(3) grain was detected at the slag/reaction layer ***_(2) and CA_(6) possess relatively high melting points,which is beneficial to hindering the further penetration of ***,the dissolution of Al_(2)O_(3) into slag is still the main cause for refractories *** increase in the MnO content of mold slag decreases the viscosity and then results in the severe corrosion of Al_(2)O_(3)-C bricks.

关键词： Al_(2)O_(3)-C refractory MnO-containing slag Graphite Corrosion

Sedimentary and Heavy Mineral Records for the Oligocene-Miocene Exhumation of the Easternmost Tianshan

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Journal of Earth Science 2024年第2期35卷 449-461页

作者： Yan Ding Tianyi Shen Guocan Wang Junliang Ji School of Earth Sciences Center for Global TectonicsChina University of GeosciencesWuhan430074China state key laboratory of Geological processes and Mineral Resources China University of GeosciencesWuhan430078China Hubei key laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan430074China

The topography of the Harlik Mountain has a strong impact on the formation of current arid climate in the Turpan-Hami ***,it is still controversial if Harlik Mountain experienced significant exhumation during the Middle to Late Cenozoic according to the previous thermochronology *** features of the Oligocene to Miocene sediments in the foreland basin could provide productive information for resolving the *** peak ages of detrital apatite fission track analysis of the Oligocene–Miocene sandstone in the Turpan-Hami Basin are well comparable with the cooling age records of the Harlik Mountain rocks,indicating that the Oligocene–Miocene Taoshuyuanzi Formation in the basin was mostly derived from the Harlik *** stratigraphic sequence exhibits coarsening upward,reflecting that the source area was in a tectonically active period during the deposition *** mineral assemblages also suggest that the unstable minerals in the sediment increased significantly at the end of the ***,the proportion of apatite increased up-section,while the garnet content decreased significantly,indicating that the Carboniferous metamorphic rocks have been gradually eroded out and more intrusive rocks have been exposed to the *** observations suggest that the Harlik Mountain experienced exhumation during the Oligocene to Miocene,and the denudation depth afterward was probably less than 2.5 km according to the previously apatite(U-Th)/He *** Oligocene–Miocene exhumation probably acted as one of the triggers for the heavy drought of the Turpan-Hami Basin during the Middle–Late Neogene.

关键词： Turpan-Hami Basin Harlik Mountain Taoshuyuanzi Formation Oligocene–Miocene uplift sedimentology structural geology