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Carbon Isotope Features of the Sugetbrak Section in the Aksu-Wushi Area, Northwest China: Implications for the Precambrian/Cambrian Stratigraphic Correlations

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1535-1546页

作者： YAO Chunyan DING Haifeng MA Dongsheng li guoxiang Nanjing Center China Geological Survey Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

The upper Qigeblaq Formation （Fm） dolostones and the Yurtus Fm phosphatic cherts, black shales, limestones, and dolostones are widely distributed in the Precambrian/Cambrian transitional succession of the Aksu-Wushi area. Negative δ13C excursion above the Yurtus Fm/ Qigeblaq Fm boundary was determined in this study. The pronounced negative carbon isotope excursion occurs in the phosphatic chert layers at the bottom of the Cambrian Yurtus Fm, below which the first appearance of the Asteridium- Heh＇osphaeridium-Comasphaeridium （AHC） acritarch assemblage zone. The δ13C curve of the lower part of the Yurtus Fm in the Aksu-Wushi area was found to be correlated with the early Cambrian δ13C curves of the Zhujiaqing Fm （Daibu Member）, the lower part of the Yanjiahe Fm on the Yangtze Platform in China, the lower Tal Fm in India, the Sukharikha Fm in Siberia, and the upper part of the Tsagaan Oloom Fm in Mongolia through biostigraphy. The lower part of the Yurtus Fm in the Tarim Basin is at the Nemakit-Daldynian stage, and the Precambrian/Cambrian boundary of the Aksu-Wushi area may be located in the phosphatic chert unit which just below the first appearance AHC acritarch assemblage zone. The negative δ13C excursion （N1） across the Precambrian/Cambrian boundary in the studied section may have resulted from oceanic overturning and sea level rise.

关键词： Carbon isotope Stratigraphic correlation Precambrian/Cambrian boundary Northwest China

计及沼气重整制氢和燃气掺氢的综合能源系统优化调度

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三峡大学学报（自然科学版） 2025年第1期47卷 89-98页

作者：王守文袁莹超徐丽洁叶金根李国祥李志明三峡大学法学与公共管理学院湖北宜昌443002 三峡大学电气与新能源学院湖北宜昌443002 三峡大学经济与管理学院湖北宜昌443002 国家电网宜昌市高新区供电公司湖北宜昌443000

为推动氢能多元生产和利用,提出一种计及沼气重整制氢和燃气掺氢的综合能源系统优化调度模型.首先,构建沼气重整制氢模型,满足天然气负荷的同时,实现生物天然气制氢.其次,将电解水和沼气重整产生的氢气联合,探究沼气重整制氢对系统经济... 详细信息

为推动氢能多元生产和利用,提出一种计及沼气重整制氢和燃气掺氢的综合能源系统优化调度模型.首先,构建沼气重整制氢模型,满足天然气负荷的同时,实现生物天然气制氢.其次,将电解水和沼气重整产生的氢气联合,探究沼气重整制氢对系统经济性、低碳性的影响.然后,生成的氢气供给氢燃料电池、掺氢燃气轮机,并引入阶梯碳交易机制,限制系统碳排放.最后,以日运行总成本最低为目标函数,设置4种不同场景进行仿真分析.仿真结果表明:所提模型总成本降低5.33%,碳排放量降低5.17%;合适的秸秆价格有利于消纳风光和利用生物质能;燃气轮机适度掺氢燃烧可以进一步降低总成本和碳排放量.

关键词：沼气重整制氢电解水制氢燃气掺氢阶梯碳交易低碳经济调度

LARRAZA-PUTTERMAN EQUATION INCLUDING VISCOSITY AND EXTERNAL DRIVE

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Chinese Journal of Acoustics 1989年第2期8卷 163-169页

作者： YAN Jiaren, HUANG guoxiang and li Hong(Xiangtan University) Xiangtan Univ

The weak nonlinear modulation of the surface wave of a three-dimensional imcompressible fluid without rotation, which is contained in a rectangular trough is studied by using the method of multiple scales perturbation theory. The effects of viscid and external drive on the motion, which modifies the Larraza- Putterman equation, are considered. The results are consistent with that of Miles.

关键词： LARRAZA-PUTTERMAN EQUATION INCLUDING VISCOSITY AND EXTERNAL DRIVE

CFD-Based Optimization of a Diesel Engine Waste Heat Recycle System

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Fluid Dynamics & Materials Processing 2023年第6期19卷 1479-1493页

作者： Da li Guodong Zhang Ke Sun Shuzhan Bai guoxiang li School of Energy and Power Engineering Shandong UniversityJinan250061China

A dedicated heat exchanger model is introduced for the optimization of heavy-duty diesel *** model is a prerequisite for the execution of CFD simulations,which are used to improve waste heat recovery in these *** optimization methods coupled with different types of working fluids are compared in terms of exergy efficiency and heat exchanger *** three considered optimization methods all lead to significant improvements in the R245fa and R1233zd systems with a comparatively low evaporation *** optimal R245fa system has the highest efficiency increase(77.49%).The cyclopentane system displays the highest efficiency among the optimized ORC(Organic Rankine Cycle)systems,yet achieved by using a much heavier evaporator HEC(Heat Exchanging Core).In contrast,the 96.84%efficiency increase for the optimized R1233zd is achieved with only 68.96%evaporator weight.

关键词： Tube-fin heat exchanger heat exchanging core organic rankine cycle working fluid

Influence of Urea Uneven Injection on the Performances of a Diesel Engine

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Fluid Dynamics & Materials Processing 2023年第1期19卷 83-93页

作者： Chang Huang Shuzhan Bai guoxiang li Ke Sun School of Energy and Power Engineering Shandong UniversityJinan250061China

The influence of heterogeneous flow injection of urea at different velocities and temperatures on NO x conversion efficiency,ammonia storage and ammonia leakage is investigated experimentally.A diesel engine employing a selective catalytic reduction(SCR)technology is *** is found that for a fixed injection velocity,the degree of ammonia leakage changes depending on the *** higher the temperature,the faster the catalytic reduction reaction and the smaller the degree of ammonia *** temperature has a great influence on the catalytic reduction reaction *** an injection velocity of 10000/h,the average reaction rate at 420℃ is 12 times higher than that at 180℃.The injection velocity has a weak influence on the reaction *** the injection velocity changes from 10000/h to 40000/h at the same temperature,the average reaction rate does not change ***,increasing the space velocity can accelerate the leakage of ammonia,thereby miti-gating the benefits associated with the NO_(x) conversion.

关键词： Diesel engine ammonia leak conversion efficiency the urea flow

Research on ECMS Based on Segmented Path Braking Energy Recovery in a Fuel Cell Vehicle

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Energy Engineering 2024年第1期121卷 95-110页

作者： Wen Sun Meijing li guoxiang li Ke Sun Shuzhan Bai School of Energy and Power Engineering Shandong UniversityJinan250061China Automotive Research Institute China National Heavy Duty Truck Group Co.Ltd.Jinan250061China

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal combustion engines in *** fuel cells cannot recover energy and have a slow dynamic response,they need to be used with different power *** efficient energy management strategies to achieve excellent fuel economy is the goal of *** paper proposes an adaptive equivalent fuel minimum consumption strategy(AECMS)to solve the problem of the poor economy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional *** this method,the kinematics interval is used to update the equivalent factor by considering the penalty term of energy recovery on SOC ***,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy *** results under the New European Driving Cycle show that compared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel economy by 1.7%while ensuring vehicle power and increases SOC by 30%.

关键词： Fuel cell PEMFC electric vehicle equivalent consumption minimization strategy

Early Cambrian Mollusc Watsonella crosbyi:A Potential GSSP Index Fossil for the Base of the Cambrian Stage 2

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 309-319页

作者： li guoxiang ZHAO Xin Alexander GUBANOV ZHU Maoyan NA lin State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontologythe Chinese Academy of Sciences Nanjing 210008 China CASP Department of Earth Sciences University of Cambridge Cambridge UK

The mollusc Watsonella crosbyi was studied on the basis of material from the lower Cambrian Dahai Member of the Zhujiaqing Formation in eastern Yunnan, China and the Pestrotsvet Formation of the Aldan River region in the Siberian Platform. This fossil had been excessively described under different names in the literature, such as Heraultia varensalensis Cobboid, 1935, H. sibirica Missarzhevsky, 1974, Heraultipegma yunnanensis He and Yang, 1982, H. yannanese He and Yang,1982, Watsonella yunnanensis, W. crosbyi Grabau, 1900, etc. Taxonomic revision shows that other species are junior synonyms of W. crosbyi. Analysis of functional morphology implies that W. crosbyi may be rather a heicionelloid than a rostroconch since its univalved conch is untorted endogastric and lacks a rostrum and a true internal pegma. Replicas of the original microstrnctures preserved on the surfaces of phosphatic internal moulds confirm that the shell consists of two layers. The inner layer is lamello-fibrillar, and the outer layer is spherulitic prismatic. The widespread geographical occurrences in both siliciclastic and carbonate rocks of the late Terreneuvian indicate that W. crosbyi is an important index fossil for global correlations and subdivision of the Cambrian Series I （Terreneuvian）.The first appearance datum （FAD） of W. crosbyi is suggested to be a potential GSSP （Global Boundary Stratotype Section and Point） candidate marker for defining the base of the Cambrian Stage 2.

关键词： mollusc Watsonella crosbyi microstructure Terreneuvian Cambrian Stage 2 South China Siberian Platform

A comparison of the biological,geological events and environmental backgrounds between the Neoproterozoic-Cambrian and Permian-Triassic transitions

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Science China Earth Sciences 2010年第12期53卷 1873-1884页

作者： ShuZhong Shen MaoYan Zhu XiangDong Wang guoxiang li ChangQun Cao Hua Zhang Chinese Acad Sci State Key Lab Palaeobiol & Stratig Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the *** studies suggest that these two critical transitions showed certain comparability in major evolutionary *** other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T *** events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass *** coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and *** supercontinent Rodinia began to rift before the Snowball Earth *** contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to *** data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem *** is indicated by the disappearance of the whole Ediacaran biota at the N-C *** subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ***,the end-Permian mass extinction is manifested mainly by the extin

关键词： Neoproterozoic-Cambrian Permian-Triassic transition biological events geological events environmental background

A Chengjiang-type fossil assemblage from the Hongjingshao Formation(Cambrian Stage 3) at Chenggong, Kunming, Yunnan

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Chinese Science Bulletin 2014年第25期59卷 3169-3175页

作者： Han Zeng Fangchen Zhao Zongjun Yin guoxiang li Maoyan Zhu State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences University of Chinese Academy of Sciences

A new Chengjiang-type fossil assemblage is reported herein from the lower part of the Hongjingshao Formation at Xiazhuang village of Chenggong,Kunming,*** fossil assemblage,named as Xiazhuang fossil assemblage,yields predominantly soft-bodied fossils,including arthropods,brachiopods,priapulids,lobopods and some problematic taxa,with arthropods being the most dominant *** and composition of the fossil assemblage are very similar to the typical Chengjiang biota,which is preserved in the middle Yu’anshan Formation in the large area of eastern *** associated trilobites demonstrate that the soft-bodied fossil assemblage belongs to the late Qiongzhusian in age(Stage 3,Cambrian),suggesting that the Hongjingshao Formation is probably a diachronous lithostratigraphic unit ranging from the upper Qiongzhusian to the lower Canglangpuan stages in eastern *** fossil assemblage from the Xiazhuang area fills up the missing link between the typical older Chengjiang biota and the younger Malong and Guanshan biotas,making eastern Yunnan a unique area in the world to reveal the early evolutionary history of animals and palaeocommunity dynamics during the‘‘Cambrian explosion’’.

关键词：化石组合云南澄江昆明寒武系寒武纪大爆发澄江生物群岩石地层单元节肢动物