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Discovery of Pseudofrenelopsis gansuensis from the Lower Cretaceous of Wangqing,Jilin Province,and Its Significance in Correlation of Cretaceous Red Beds in China

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 905-910页

作者： yang Xiaoju DENG Shenghui Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing Jiangsu 210008 Research Institute of Petroleum Exploration and Development Beijing 100083

New data from abundant vegetative shoots and cuticular analysis are provided for the Cretaceous cheirolepidiaceous conifer Pseudofrenelopsis gansuensis Deng, yang et Lu. The material was found from a new locality of the Lower Cretaceous strata in the Luozigou Basin, Wangqing, Jilin Province, northeastern China. Pseudofrenelopsis is a common plant in the Dalazi Formation of the Yanji Basin about 150 km from Wangqing, but there exists different species, Pseudofrenelopsis dalatzensis only. Both P. dalatzensis and P. gansuensis have been recorded from the Lower Cretaceous of Jiuquan, Gansu Province, but they are in different stratigraphic horizons. The Lower Cretaceous plant-bearing strata in Luozigou have used to correlate with the Dalazi Formation of the Yanji Basin. The discovery of P. gansuensis, which is lower in horizon than P. dalatzensis in Jiuquan, may indicate that they are also different in horizon in Jilin. Cheirolepidiaceous conifers are among the few fossils of red beds of the Early Cretaceous in China. The present discovery of Pseudofrenelopsis gansuensis provides important evidence for classification, correlation and determination of geological ages of the Early Cretaceous non-marine red deposits of the two separate basins in remote areas of North China.

关键词： Cheirolepidiaceae Cretaceous Dalazi Formation Pseudofrenelopsis red beds,stratigraphic correlation

The Most Likely Common Difference of Arithmetic Progressions Among Primes

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Communications in Mathematics and Statistics 2021年第3期9卷 315-329页

作者： Xiaosheng Wu Pengzhen yang School of Mathematics Hefei University of TechnologyHefei 230009People’s Republic of China

Let d^(∗)_(k)(x)be the most likely common differences of arithmetic progressions of length k+1 among primes≤*** on the truth of Hardy–Littlewood Conjecture,we obtain that lim x→+∞d^(∗)_(k)(x)(x)=+∞uniformly in k,... 详细信息

关键词： Common difference Arithmetic progression Hardy–Littlewood Conjecture Differences among primes Singular series

Accelerated Exhumation During the Cenozoic in the Dabie Mountains: Evidence from Fission-Track Ages

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Acta Geologica Sinica(English Edition) 1998年第4期72卷 409-419页

作者： WANG Guocan yang Weiran Faculty of Earth Science China University of Geosciences Wuhan Hubei 430074

Abstract: Zircon and apatite fission-track dating indicates that the exhumation of the Dabie Mountains tended to be accelerated in the Cenozoic and that the exhumation of the eastern Dabie Mountains was more and more intense from south to north, which is in accordance with the more and more intense dissection from south to north, as is reflected by the modern geomorphologic features of the Dabie Mountains. The accelerated exhumation during the Cenozoic was related to the high elevation of the Dabie Mountains resulting from Late Cretaceous-Palaeogene detachment faulting and subsequent fault-block uplift and subsidence. The average elevation at that time was at least about 660 m higher than that at the present. The intense exhumation lagged behind intense uplift.

关键词： Dabie Mountains accelerated exhumation Cenozoic fission-track age

Effects of Irregular Wave Groups on Pile Forces

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China Ocean Engineering 1991年第2期6卷 175-190页

作者： yang, Zhengji Zuo, Qihua Nanjing Hydraulic Research Inst Nanjing China

The wave forces on 1,2 and 4 vertical circular piles under the action of several wave trains of the same wave parameters, such as Hs Tp and Mo, but different wave group factors GF are measured in the laboratory. After comparing these forces, it may be concluded that the mean and significant wave forces are almost of no difference for the wave trains with different GF. When GF is larger, the one-tenth of the wave force extreme is slightly increased and the maximum wave force is much larger than the ones with smaller GF, to which attention must be paid in engineering practice.

关键词： Water Waves Wave Effects

Petrogenesis and Tectonic Implications of Jurassic Granites in the Xingcheng Area,Northeastern North China Craton

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1483-1492页

作者： MU Maosong yang Debin XU Wenliang QUAN Yikang HAO Leran yang Haotian WANG Anqi College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China

New integrated geochemical studies are reported for Jurassic granites of the Xingcheng area in the northeastern North China Craton.U-Pb zircon data indicate that the Huashan and Taili monzogranites were emplaced during the Early(189±2 Ma)and Late(155±1 Ma)Jurassic,*** are typical of high-K calc-alkaline series rocks and I-type granites,according to our whole-rock geochemical *** Early and Late Jurassic monzogranites show adakitic rock characteristics because of their high Sr contents(221-347 ppm)and Sr/Y ratios(28.7-37.5),and low Y contents(7.83-14.7 ppm).The Early Jurassic monzogranite samples have an(^(87)Sr/^(86)Sr)i ratio of 0.7046,ε_(Nd)(t)values of -11.62 to -11.51,and ε_(Hf)(t)values of -13.6 to-6.4,whereas the Late Jurassic monzogranites have higher(87Sr/86Sr)i ratios of 0.7069-0.7071and lower ε_(Nd)(t)(-20.65 to-20.46)and ε_(Hf)(t)(-27.6 to-20.0)*** suggest that the Early Jurassic adakitic rocks were derived from partial melting of thickened lower crust contaminated with mantle-derived materials,related to subduction of the Paleo-Pacific *** Late Jurassic adakitic rocks were derived from partial melting of thickened lower crust in an extensional tectonic setting associated with an active continental margin.

关键词： geochemistry petrology monzogranite adakite North China Craton

A chorismate mutase from Radopholus similis plays an essential role in pathogenicity

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Journal of Integrative Agriculture 2024年第3期23卷 923-937页

作者： Sihua yang Junyi Li Shuai yang Shiqiao Tang Huizhong Wang Chunling Xu Hui Xie Laboratory of Plant Nematology andResearch Centerof Nematodes of Plant Quarantine Department of Plant Patholo of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China

In the process of infecting plants, plant parasitic nematodes release a series of proteins that play an essential role in the successful infection and pathogenesis of plant cells and tissues through stylets or body walls. In this study,based on transcriptome data, a chorismate mutase gene of Radopholus similis(RsCM) was identified and cloned,which is a single copy gene specifically expressed in the oesophageal gland and highly expressed in juveniles and females. Transient expression of RsCM in tobacco leaves showed that it was localised in the cytoplasm and nucleus of tobacco leaf cells, which inhibited the pattern-triggered immunity(PTI) induced by flg22, including callose deposition and defence gene expression, and cell death induced by immune elicitors BAX, but could not inhibit cell death induced by immune elicitors Gpa2/RBP-1. The RNA interference(RNAi) transgenic tomato of RsCM obviously inhibited the infection, pathogenicity, and reproduction of R. similis. However, the resistance of the overexpression transgenic tomato of RsCM to R. similis infection was significantly reduced, and the expression levels of two salicylic acid(SA) pathway genes(PR1 and PR5) in roots infected by the nematode were significantly down-regulated,which indicated that RsCM might be involved in the inhibition of SA pathway. The results of this study demonstrate that RsCM suppresses the host immune system and might be a new target for the control of R. similis, which also provides new data for the function and mechanism of CM genes of migratory parasitic plant nematodes.

关键词： Radopholus similis chorismate mutase plant defense transgenic tomato

Application of C_(30)tetracyclic polyprenoids as effective biomarker in oil-to source rock correlation in the ZhuⅢdepression,Zhujiangkou Basin,northern South China

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Acta Oceanologica Sinica 2024年第8期43卷 37-46页

作者： Lei Lan Youchuan Li Shuchun yang yang Ouyang Wenjing Ding Qing Lin Shanshan Zhou CNOOC Research Institute Co. Ltd.Beijing 100028China

The northern South China Sea,including the Zhujiangkou Basin and the Beibuwan Basin,developed high-quality lacustrine source rocks during the Eocene rifting *** source rocks are vital for hydrocarbon generation in the northern South China *** ZhuⅠdepression in the Zhujiangkou Basin and the Beibuwan Basin typically exhibit high abundance of C_(30)4-methyl ***,shales in the Eocene Wenchang Formation in the ZhuⅢdepression of the Zhujiangkou Basin contains lower quantities of high-quality lacustrine source rocks with 4-methyl steranes,which often co-elute with some pentacyclic triterpanes in gas chromatography-mass spectrometry(GC-MS).Therefore,the single 4-methylsterane parameter based on GC-MS cannot accurately distinguish organic source in the deep to semi-deep water lacustrine source rocks of the Wenchang Formation from other source rocks,thus impeding the recognition of their contributions to petroleum *** this study,GC-MS of aliphatic hydrocarbons,palynofacies and algal identification,as well as stable carbon isotope data of organic matter were used to identify the algal species and construct the paleoclimate during deposition of the Wenchang Formation source rocks in the ZhuⅢdepression of the Zhujiangkou *** is suggested that during the Wenchang Formation period,freshwater green algae prevailed in the lake,which is likely account for the relatively low content of 4-methyl steranes in the high-quality lacustrine source *** by the algal species,it is proposed that the content of C_(30)tetracyclic polyprenoids(TPP)can better indicate the quality of the Wenchang source rocks than C_(30)4-methyl ***,a relationship between the TPP index and the quality of the lacustrine source rocks in the Wenchang Formation of the ZhuⅢdepression was established.A higher TPP index indicates higher organic matter abundance and hydrogen index of the lacustrine source *** applied to the origin analysis of oils

关键词： lacustrine source rocks C_(30)tetracyclic polyprenoids green algae Zhujiangkou Basin

Vector kink-dark complex solitons in a three-component Bose–Einstein condensate

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Communications in Theoretical Physics 2021年第5期73卷 85-91页

作者： Yan Li Yan-Hong Qin Li-Chen Zhao Zhan-Ying yang Wen-Li yang School of Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127 China Peng Huanwu Center for Fundamental Theory Xi’an 710127China

We investigate kink-dark complex solitons(KDCSs)in a three-component Bose–Einstein condensate(BEC)with repulsive interactions and pair-transition(PT)*** profiles critically depend on the phase differences between dark solitons excitation *** report a type of kink-dark soliton profile which shows a droplet-bubble-droplet with a density dip,in sharp contrast to previously studied *** interaction between two KDCSs is further *** demonstrates some striking particle transition behaviours during their collision processes,while soliton profiles survive after the ***,we exhibit the state transition dynamics between a kink soliton and a dark *** results suggest that PT effects can induce more abundant complex solitons dynamics in multi-component BEC.

关键词： kink-dark complex solitons pair-transition effects three-component Bose–Einstein condensate

Mechanical reliable,NIR light-induced rapid self-healing hydrogel electrolyte towards flexible zinc-ion hybrid supercapacitors with low-temperature adaptability and long service life

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Journal of Energy Chemistry 2024年第5期92卷 63-73页

作者： Tengjia Gao Na Li yang yang Jing Li Peng Ji Yunlong Zhou Jianxiong Xu School of Materials and Advanced Manufacturing Hunan Key Laboratory of Electrochemical Green Metallurgy TechnologyHunan University of TechnologyZhuzhou 412007HunanChina School of Life Sciences and Chemistry Hunan Key Laboratory of Biomedical Nanomaterials and DevicesHunan University of TechnologyZhuzhou 412007HunanChina

Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and ***,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ***,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible ***,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated Sb_(2)S_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing *** addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 S m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 MPa with tensile elongation of 760%,together with fracture energy of 5.14 MJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illumination,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°***,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°***,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°*** contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span.

关键词： Flexible zinc ion supercapacitor Hydrogel electrolyte Self-healing Anti-freezing