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Reference Interval of Thyroidal Function of Women in the Early,Middle and Late Pregnancy in Jingzhou City,Hubei Province
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作者 Hongying WU Kai DING 《Medicinal Plant》 2024年第5期1-3,共3页
[Objectives]To study the reference value of thyroid function in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City.[Methods]362 healthy women of childbearin... [Objectives]To study the reference value of thyroid function in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City.[Methods]362 healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)were selected as the study group,and 360 non-pregnant women were selected as the control group.Serum thyroid hormone levels in the two groups were detected,and the reference value was expressed as the median(M)and 95%confidence interval(CI).On this basis,the chart of changing trend of thyroid hormone in the early,middle and late pregnancy were plotted.[Results]Compared with the control group,FT3,TT4,TT3,FT4and TSH in the early,middle and late pregnancy were significantly different in the study group(P<0.05).In the study group,there were significant differences in the early,middle and late pregnancy(P<0.05).[Conclusions]This trend chart has certain reference value in the screening,diagnosis and treatment of thyroid diseases in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City of Hubei Province. 展开更多
关键词 EARLY middle and late pregnancy Thyroid function Reference value Thyroid hormone
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An Updated Review of the Middle-Late Jurassic Yanliao Biota: Chronology,Taphonomy,Paleontology and Paleoecology 被引量:7
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作者 XU Xing ZHOU Zhonghe +2 位作者 Corwin SULLIVAN WANG Yuan REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2229-2243,共15页
The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning,... The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning, northern Hebei, and southeastern Inner Mongolia. The biota lasted for about 10 million years, divided into two phases: the Bathonian-Callovian Daohugou phase (about 168-164 million years ago) and the Oxfordian Linglongta phase (164-159 million years ago). The Yanliao fossils are often taphonomically exceptional (many vertebrate skeletons, for example, are complete and accompanied by preserved integumentary features), and not only are taxonomically diverse but also include the oldest known representatives of many groups of plants, invertebrates, and vertebrates. These fossils have provided significant new information regarding the origins and early evolution of such clades as fleas, birds, and mammals, in addition to the evolution of some major biological structures such as feathers, and have demonstrated the existence of a complex terrestrial ecosystem in northeast China around the time of the Middle-Late Jurassic boundary. 展开更多
关键词 Yanliao Biota Daohugou phase Linglongta phase middle-late jurassic Yanliao area
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Relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine fetal distress
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作者 Ji Chen Fei-Xue Liu Rui-Xue Tao 《World Journal of Clinical Cases》 SCIE 2024年第16期2745-2750,共6页
BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that t... BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that timely interventions can be implemented to safeguard the health and safety of the fetus.AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress.METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups(n=50 each),according to the presence or absence of intrauterine distress.The ultrasound hemodynamic parameters of the uterine artery(UtA),fetal middle cerebral artery(MCA),and umbilical artery(UmA)were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups.RESULTS Comparison of ultrasonic hemodynamic parameters,resistance index(RI),pulsatility index(PI),and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity(S/D),revealed higher values of fetal MCA,PI,and S/D of UmA in pregnant women with UtA compared to controls(P<0.05),while there was no difference between the two groups in terms of RI(P<0.05)The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group(66.7%)than in the control group(90.0%),and neonatal weight(2675.5±27.6 g)was lower than in the control group(3117.5±31.2 g).Further,cesarean section rate was higher in the observation group(70.0%)than in the control group(11.7%),and preterm labor rate was higher in the observation group(40.0%)than in the control group(10.0%).The incidence of fetal distress,neonatal growth restriction and neonatal asphyxia were also higher in the observation group(all P<0.05).CONCLUSION Fetal MCA,UmA,and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy,which suggests that clinical attention should be paid to them,and monitoring should be strengthened to provide guidance for clinical intervention. 展开更多
关键词 late pregnancy Fetal intrauterine distress Ultrasound blood flow parameters Uterine artery middle cerebral artery Umbilical artery
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A New Darwinopterid Pterosaur from the Middle Jurassic of Western Liaoning,Northeastern China and its Ecological Implications 被引量:13
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作者 Lu Junchang XU Li +1 位作者 CHANG Huali ZHANG Xingliao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期507-514,共8页
A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-... A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-like teeth;the longest teeth are confined to the anterior half of the tooth row;tooth alveoli have raised margins;nasoantorbital fenestra confluent;inclined quadrate;elongate cervical vertebrae with low neural spine and reduced or absent ribs;long tail of more than 20 caudals partially enclosed by filiform extensions of the pre-and postzygapophyses;short metacarpus less than 60 per cent length of humerus,fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees.The complete specimen of the new pterosaur D.robustodens sp.nov.provides much more osteological information.The differences in tooth morphologies between Darwinopterus modularis and D.robustodens sp.nov.suggest that they filled different ecological niches.The hard integument-bearing Coleoptera may have been the main food source of Darwinopterus robustodens. 展开更多
关键词 Darwinopterus robustodens Tiaojinshan Formation middle jurassic western Liaoning China
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Intracontinental Collisional Orogeny During Late Permian-Middle Triassic in South China: Sedimentary Records of the Shiwandashan Basin 被引量:12
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作者 LIANGXinquan LIXianhua QIUYuanxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期756-762,共7页
Sedimentary response to an orogenic process is important for determining whether South China had compressional or extensional orogeny during the period from the Late Permian to the Middle Triassic besides the tectonic... Sedimentary response to an orogenic process is important for determining whether South China had compressional or extensional orogeny during the period from the Late Permian to the Middle Triassic besides the tectonic and magmatologic evidence. An intracontinental collision event took place between the Yangtze and Cathaysia blocks in the Late Permian. Beginning at the Late Triassic, the tectonic movement was completely changed in nature and entered a post-collisional extensional orogenic and basin-making process. This paper presents sedimentological evidence from the Late Permian to the Middle Triassic in the Shiwandashan basin at the southwestern end of the junction zone between the Yangtze and Cathaysia blocks. 展开更多
关键词 Shiwandashan basin intracontinental collisional orogeny sedimentary record late Permian to middle Triassic South China.
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Cuticles and Spores in Situ of Coniopteris hymenophylloides from the Middle Jurassic in Gansu, Northwestern China 被引量:5
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作者 XIN Cunlin WANG Luhan +2 位作者 DU Baoxia ZHANG Yamei WANG Jingjing 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第3期904-914,共11页
Coniopteris was a ubiquitous plant of the Jurassic and Cretaceous periods and played an important role in the flora of the time. However, its anatomical structure is relatively poorly known. The specimens of Coniopter... Coniopteris was a ubiquitous plant of the Jurassic and Cretaceous periods and played an important role in the flora of the time. However, its anatomical structure is relatively poorly known. The specimens of Coniopteris hymenophylloides(Brongniart) Seward described here were collected from the Yaojie Formation in Gansu Province, northwestern China. The sterile fronds are characterized as being at least bipinnate with alternate arranged linear pinnae covered by thin cuticles. Fertile fronds are linear-lanceolate, with single sorus at the margin of each fertile pinnule. In situ spores are typically trilete, triangle to subcircular in polar view, cap-shaped in equatorial view, and 37 μm in average diameter. The trilete marking is straight and narrow, generally extends to 4/5 of the spore radius. The spore surface is smooth, and parts of the exine are granulated. The epidermal cells of cuticles are irregular in shape, approximately 40-60μm long and 10-20 μm wide. The elliptical stomatal complexes are paracytic,approximately 30 μm long and 19 μm wide,and irregularly distributed. On the basis of its epidermal structures and comparisons with extant ferns, we consider that Coniopteris displays combined features of the related extant genera. 展开更多
关键词 Coniopteris hymenophylloides spore in situ cuticle middle jurassic Yaojie Formation GANSU China
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Geological and geochemical characteristics of Middle Jurassic granites in Bengbu uplift, Southeast of North China craton 被引量:5
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作者 Kang Congxuan Yang Xianzhong +2 位作者 Cai Yitao Zong Wen Zhu Xiaoting 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期83-85,共3页
1 Introduction The early formation and evolution of the North China craton has been widely concerned by scientists.The Bengbu uplift belt is located in the southeast of the craton,theresearch degree of the belt is rel... 1 Introduction The early formation and evolution of the North China craton has been widely concerned by scientists.The Bengbu uplift belt is located in the southeast of the craton,theresearch degree of the belt is relatively low and received increasing attention from many scholars in recent years.Through the author’s practical work and combined with 展开更多
关键词 area PB Geological and geochemical characteristics of middle jurassic granites in Bengbu uplift ROCK
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New Discovery of Reproductive Organs and Spores in Situ of Ginkgoales and Czekanowskiales from the Middle Jurassic of Shaanxi, China 被引量:1
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作者 GUO Caiqing YAO Jianxin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2314-2315,共2页
Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abunda... Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abundant in the Middle Jurassic of Shaanxi Province, but there are no reports on their reproductive organs. Here, we report two male gymnospermous pollen cones from the Middle Jttrassic Yan'an Formation of the northeast Yulin City, Shaanxi Province, China. The characteristics of the fossils, including those of pollens, have been described in detail. The new specimens were compared with fossils closely similar in morphology, and the taxonomic affinity and systematies were established. The present results offer new fossil materials for the study of taxonomy, evolution, and phytogeography of Ginkgoales and Czekanowskiales. 展开更多
关键词 New Discovery of Reproductive Organs and Spores Situ of Ginkgoales Czekanowskiales from the middle jurassic of Shaanxi
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Structural Characteristics and Evolution of Jurassic Basins in the East of Middle Qilian Block 被引量:1
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作者 郑孟林 李明杰 +2 位作者 曹春潮 张勇军 徐世陆 《Journal of China University of Mining and Technology》 2003年第1期35-39,共5页
Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows th... Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows that each of these three basins is an independent structural unit with a NW strike and being separated by upheavals. Two groups of faults with NW and NE directions are developed in the basin, which controls the formation and evolution of the (Jurassic basins). The NW faults are the main ones while the NE faults are the secondary for controlling the sedimentation. Of the three basins, the Minhe basin is the favorable prospecting area. 展开更多
关键词 east of middle Qilian jurassic basin structural characteristic EVOLUTION prospecting of oil and gas
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Field Efficacy Trial and Optimum Control Period of Rice False Smut(Ustilaginoidea virens) in Single Cropping Middle-late Rice 被引量:2
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作者 Liu Huaizhen Li Kanghuo +5 位作者 Huang Qing Lu Xiuming Zhang Bin Li Huifeng Zou Jixiang Zhou Shaochuan 《Plant Diseases and Pests》 CAS 2014年第2期31-34,共4页
[Objective]The paper was to study optimum chemical agents and control periods against rice false smut( Ustilaginoidea virens) in single cropping middle-late rice. [Method]Taking chemical agents( triadimefon,armure,Jin... [Objective]The paper was to study optimum chemical agents and control periods against rice false smut( Ustilaginoidea virens) in single cropping middle-late rice. [Method]Taking chemical agents( triadimefon,armure,Jinggangmycin) as main treatments and spraying periods( within 7 d before initial heading stage,within 7 d before initial heading stage + initial heading stage,initial heading stage) as assisted treatments,the field efficacy trial and optimum control period of U. virens in single cropping middle-late rice were studied using Huanghuazhan and Jinnongsimiao as experimental materials in 2013. [Result] Three chemical agents,triadimefon,armure,Jinggangmycin,extremely reduced diseased panicle rate and disease index of U. virens,but there was no significant difference among three chemical agents. Spraying period did not have significant impact on diseased panicle rate and disease index of U. virens,whereas spraying within7 d before initial heading stage and during initial heading stage had relatively good control effect. Yield increased significantly after application of three chemical agents,and armure led to greater increase. The reason for yield increase was that seed setting rate was significantly increased,and the number of filled grains per panicle was significantly increased. Although spraying period influenced yield,the difference was not significant. [Conclusion] Triadimefon,armure and Jinggangmycin had good control effects against U. virens in single cropping middle-late rice,of which armure had better control effects. Spraying chemical agents increased seed setting rate,and further increased the number of filled grains per panicle and yield. Spraying within 7 d before initial heading stage and during initial heading stage had relatively better control effect against U. virens. 展开更多
关键词 Single cropping middle-late rice Ustilaginoidea virens Field efficacy test
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A New Species of Ginkgo with Male Cones and Pollen Grains in situ from the Middle Jurassic of Eastern Xinjiang,China
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作者 WANG Zixi SUN Fankai +5 位作者 JIN Peihong CHEN Yingquan CHEN Jingwei DENG Peng YANG Guolin SUN Bainian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期9-21,共13页
Well-preserved Ginkgo pollen organs are analyzed from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China, and are described as a new species, Ginkgo... Well-preserved Ginkgo pollen organs are analyzed from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China, and are described as a new species, Ginkgo hamiensis Z.X. Wang et B.N. Sun sp. nov. The immature male cones are cylindrical and catkin-like, with two longitudinal stripes on the stalk. The pollen sacs are shaped like a long oval with two pollen sacs fused together for each microsporophyll, and the microsporophyll tip is a triangular cystidium. The pollen grains are oblong or fusiform and monocolpate; both ends are blunt or sharp. By comparison with previously reported fossil records of Ginkgo plants, we determined that the current fossils are different from all other reported species; thus, the present fossil is referred to as a new species of Ginkgo. The reproductive organs of the Ginkgo fossils described herein can provide valuable information for the study of Ginkgo plants. Further, there are two probable evolutionary trends in the Ginkgo pollen cones. One trend is that the number of pollen sacs changed from three or four during the Jurassic and Cretaceous to two at the present day; the other is that the number of pollen sacs has remained two from the Middle Jurassic to the present day. In addition, the pollen cones described herein are similar to the pollen cones of the extant Ginkgo, which strongly indicates that the morphology of Ginkgo plants may have remained highly conserved over millions of years. 展开更多
关键词 Ginkgo hamiensis Pollen cones middle jurassic Xinjiang Uygur Autonomous Region Systematic evolution
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Characteristics and Natural Gas Origin of Middle-Late Triassic Marine Source Rocks of the Western Sichuan Depression, SW China
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作者 SUN Tengjiao LUO Xiaoping +4 位作者 QING Hairuo KOU Xueling SHENG Zhongming XU Guosheng ZUO Yinhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第2期376-398,共23页
A scientific exploration well(CK1) was drilled to expand the oil/gas production in the western Sichuan depression, SW, China. Seventy-three core samples and four natural gas samples from the Middle–Late Triassic stra... A scientific exploration well(CK1) was drilled to expand the oil/gas production in the western Sichuan depression, SW, China. Seventy-three core samples and four natural gas samples from the Middle–Late Triassic strata were analyzed to determine the paleo-depositional setting and the abundance of organic matter(OM) and to evaluate the hydrocarbon-generation process and potential. This information was then used to identify the origin of the natural gas. The OM is characterized by medium n-alkanes(n C15–n C19), low pristane/phytane and terrigenous aquatic ratios(TAR), a carbon preference index(CPI) of ~1, regular steranes with C29 > C27 > C28, gammacerane/C30 hopane ratios of 0.15–0.32, and δDorg of-132‰ to-58‰, suggesting a marine algal/phytoplankton source with terrestrial input deposited in a reducing–transitional saline/marine sedimentary environment. Based on the TOC, HI index, and chloroform bitumen "A" the algalrich dolomites of the Leikoupo Formation are fair–good source rocks;the grey limestones of the Maantang Formation are fair source rocks;and the shales of the Xiaotangzi Formation are moderately good source rocks. In addition, maceral and carbon isotopes indicate that the kerogen of the Leikoupo and Maantang formations is type Ⅱ and that of the Xiaotangzi Formation is type Ⅱ–Ⅲ. The maturity parameters and the hopane and sterane isomerization suggest that the OM was advanced mature and produced wet–dry gases. One-dimensional modeling of the thermal-burial history suggests that hydrocarbon-generation occurred at 220–60 Ma. The gas components and C–H–He–Ar–Ne isotopes indicate that the oilassociated gases were generated in the Leikoupo and Maantang formations, and then, they mixed with gases from the Xiaotangzi Formation, which were probably contributed by the underlying Permian marine source rocks. Therefore, the deeply-buried Middle–Late Triassic marine source rocks in the western Sichuan depression and in similar basins have a great significant hydrocarbon potential. 展开更多
关键词 middle to late TRIASSIC source rock CHARACTERISTICS HYDROCARBON generation and potential origin of naturalgas western SICHUAN depression
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Prevention and Control Effects of New Biological Formulations Sprayed by Different Methods on Proceras venosatus (Walker) and Tryporyza intacta Snellen in Middle and Late Stages
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作者 Li Wenfeng Shan Hongli +6 位作者 Wang Xiaoyan Zhang Rongyue Luo Zhiming Fang Chao Mao Yonglei Yin Jiong Huang Yingkun 《Plant Diseases and Pests》 CAS 2018年第3期29-32,共4页
To screen new biological formulations, accurate and efficient application technology, field test was conducted with 72% Bacillus thuringiensis(Bt)·monosultap WP, 8% lambda-cyhalothrin·emamectin benzoate SA a... To screen new biological formulations, accurate and efficient application technology, field test was conducted with 72% Bacillus thuringiensis(Bt)·monosultap WP, 8% lambda-cyhalothrin·emamectin benzoate SA and 3.6% lambda-cyhalothrin·Bt SA through manual spraying and unmanned aerial vehicle spraying. Test results and comprehensive evaluation analysis demonstrated that 72% Bt·monosultap WP and 8%lambda-cyhalothrin·emamectin benzoate SA by manual spraying and unmanned aerial vehicle spraying had good prevention and control effect on strains and internodes damaged by Tryporyza intacta Snellen in middle and late stage, which were ideal new biological formulations with high effi-ciency and low risk for prevention and control of T. intacta in middle and late stage, and could be popularized in sugarcane area. 72% Bt·monosultap WP at the dose of 3 000 g/hectare and 8% lambda-cyhalothrin·emamectin benzoate SA at the dose of 750 mL/hectare could be sprayed in mid September at the peak occurrence period of the forth and fifth generations of T. intacta and Proceras venosatus. Agents were diluted with 900 kg water per hectare, and manually sprayed with electric knapsack sprayer; or agents were diluted with 15 kg of Haoyang aerial control special addi-tives and water per hectare, and sprayed with unmanned aerial vehicle. The control effect against borer-damaged strain rate was above 81.3% and that against borer-damaged internode rate was above 88.6%. 展开更多
关键词 Biological formulation Different spraying methods Proceras venosatus (Walker) and Tryporyza intacta Snellen in middle and late stage Control effect evaluation
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Middle Jurassic—Tertiary Deposits and Ostracod—Charophyte fossil assemblages of Xining and Minhe Basins
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《地球科学》 EI CAS 1983年第S1期177-179,共3页
The Xining and the Minhe Basins bordering on each other around Ledu innorthwestern China cover a wide area from the west of Lanzhou in Gansuprovince to the east of Xining in Qinghai province.In these inland basins,Mes... The Xining and the Minhe Basins bordering on each other around Ledu innorthwestern China cover a wide area from the west of Lanzhou in Gansuprovince to the east of Xining in Qinghai province.In these inland basins,Meso-Cenozoic terrestrial deposits about 6000-7000 meters in thicknessand rich in mineral resources,such as coal,oi1 as well as salts,had beenaccumunated,which yield abundant organic remains comprising microfossils,such as nonmarine ostracods,charophytes,spores and pollen and macrofos-si1s including bivalves.gastropods,esthierians,fishes,reptiles and plants. 展开更多
关键词 Tertiary Deposits and Ostracod Charophyte fossil assemblages of Xining and Minhe Basins middle jurassic
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Middle and Late Carboniferous Tetracoral Assemblages and Biogeography of China
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作者 Wang Zhiping China University of Geosciences, Wuhan, Hubei Liu Linqun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第2期103-114,共12页
China is rich in Middle and Carboniferous fossil corals. The coral faunas in different regions have varying characteristics and can be divided into distinct assemblages. The coral fauna in South China is dominated by ... China is rich in Middle and Carboniferous fossil corals. The coral faunas in different regions have varying characteristics and can be divided into distinct assemblages. The coral fauna in South China is dominated by the order Caninida and contains numerous endemic elements; that in North China has a lot of Middle Carboniferous corals which are monotonous in species, with Late Carboniferous solitary corals being predominant. The coral fauna in Junggar mainly contains large bi-zoned solitary caninids, while that in southern Khingan is similar to that in South China due to the presence of abundant tri-zoned compound corals. In northern Tibet the coral fauna is also similar to that in South China, but in southern Tibet it is of a cold-water type. Therefore, the Middle and Late Carboniferous coral geography of China can be divided into the Tethys, Boreal and Gondwana Realms. 展开更多
关键词 LA middle and late Carboniferous Tetracoral Assemblages and Biogeography of China
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A NEW SPECIES OF OMEISAURUS FROM THE MIDDLE JURASSIC OF ZIGONG,SICHUAN 被引量:4
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作者 江山 李飞 +1 位作者 彭光照 叶勇 《古脊椎动物学报》 CSCD 北大核心 2011年第2期185-194,共10页
记述了产自四川自贡大山铺中侏罗世峨眉龙属一新种——焦氏峨眉龙(Omeisaurusjiaoisp.nov.)。新种为大型蜥脚类恐龙,以如下特征区别于其他蜥脚类:前、中部背椎为典型的后凹型,后部背椎为双平型,背椎神经棘呈高大棒状,不分叉;尾... 记述了产自四川自贡大山铺中侏罗世峨眉龙属一新种——焦氏峨眉龙(Omeisaurusjiaoisp.nov.)。新种为大型蜥脚类恐龙,以如下特征区别于其他蜥脚类:前、中部背椎为典型的后凹型,后部背椎为双平型,背椎神经棘呈高大棒状,不分叉;尾椎为弱双凹型,第一尾椎不具扇形尾肋;第一脉弧短小且与第一尾椎关联;锁骨长大;肱骨和股骨细长而圆实;肱骨与股骨长度之比为0.83,尺骨与肱骨长度之比为0.72,胫骨与股骨长度之比为0.63。 展开更多
关键词 四川自贡大山铺 中侏罗世 蜥脚类 峨眉龙
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First report of subgenus Phoenicopsis(Czekanowskiales)from Middle Jurassic of Ordos,China and its paleoclimatic implications
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作者 LI Tao LI Yunfeng +3 位作者 NA Yuling HUANG Wei TAN Xiao SUN Chunlin 《Global Geology》 2015年第3期145-154,共10页
Subgenus Phoenicopsis (Phoenicopsis) assigned to Czekanowskiales is recognized and a new species, Phoenicopsis (Ph.) ordosensis sp. nov. is first reported fi'om the Middle Jurassic Yan'an Formation of the Ordos ... Subgenus Phoenicopsis (Phoenicopsis) assigned to Czekanowskiales is recognized and a new species, Phoenicopsis (Ph.) ordosensis sp. nov. is first reported fi'om the Middle Jurassic Yan'an Formation of the Ordos Basin, alternate based upon the leaf gross morphology and epidermal structures. The new species has linear leavs in bundles of five to six attached on a short shoot, more than 100 mm long by 5-6 mm wide, containing 10-12 parallel veins at upper portion. The leaf is hypostomatic. Epidermal cells are longitudinally arranged with smooth periclinal wall on the upper cuticle. The narrow non-stomatal zones and wide stomatal zones alternate in the lower cuticle. Stomata in four to five irregular spaced rows are longitudinally oriented in each stomatal zone. Guard cells for each are surrounded by four to five subsidiary cells with undeveloped papillae. Anticlinal wails of ordinal3, epidermal cells are nearly straight and periclinal walls slightly papillate. The new species shallow stomatal pits kept open and surrounded by unevenly undeveloped bulges. These characters are consistent with those of growth in a humid, rather than an arid climate. The presence of subgenus Phoenicopsis and other taxa of Czekanowskiales in the coal-bearing Yan'an Formation supports the view that the climate in the Ordos Basin was humid and warm with seasonal changes during the Middle Jurassic. 展开更多
关键词 Subgenus Phoenicopsis (Phoenicopsis) Czekanowskiales middle jurassic ORDOS China
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Middle and Late Tertiary Palaeogeography and Palaeoenvironment on the Northern Continental Margin of the South China Sea
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作者 Duan Weiwu Huang Yongyang Guangzhou Marine Geological Survey, Ministry of Geology and Mineral Resources, Guangzhou, Guangdong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第2期211-222,共12页
Based essentially on research results of calcareous nannofossils, combined with some other microfossil da-ta and several secondary depositional breaks, this paper discusses the criteria of division and comparison of t... Based essentially on research results of calcareous nannofossils, combined with some other microfossil da-ta and several secondary depositional breaks, this paper discusses the criteria of division and comparison of themiddle and late Tertiary marine sediments, palaeogeographical and palaeoenvironmental evolution andpalaeoclimates on the northern continental margin of the South China Sea, comprising the Tainan basin, PearlRiver Mouth basin. Southeast Hainan basin and Beibu Gulf basin. Study shows that the upper Oligocene toPliocene strata in the whole area consist essentially of marine sediments except in the Beibu Gulf basin. Theyinclude littoral. neritic and deltaic sediments as well as carbonate rock-bioherm limestone. The sea advancedfrom southeast to northwest. During the transgression there appeared three culminations coinciding to thestages of deposition of nannofossil zones NN4-5, NN11 and 13-15. 展开更多
关键词 middle and late Tertiary Palaeogeography and Palaeoenvironment on the Northern Continental Margin of the South China Sea
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On the Rural Revitalization in the Middle and Late Stages of Modernization
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作者 Xu Yong 《Contemporary Social Sciences》 2020年第5期1-12,共12页
China’s rural revitalization,which was initiated in the middle and late stages of modernization,features distinct characteristics of the times.It is necessary to approach rural revitalization in China from the aspect... China’s rural revitalization,which was initiated in the middle and late stages of modernization,features distinct characteristics of the times.It is necessary to approach rural revitalization in China from the aspects of industrial-agricultural coordination,urban-rural integration,and regional balance.Industrial-agricultural coordination concerns forging the“world’s factory”and,more importantly,developing into the“world’s farm”through rural revitalization.Urban-rural integration is not just about urban modernization,but also about rural modernization through rural revitalization.Regional balance requires the promotion of characteristic development in peripheral regions with targeted measures of rural revitalization,as well as the building of highly developed city clusters. 展开更多
关键词 the middle and late stages of modernization rural revitalization industrialagricultural coordination urban-rural integration regional balance
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Analysis of Sedimentary Environment and Sequence Stratigraphy of Middle-Late Permian Sediments in Coastal Fars, Iran (Zireh Gas Field, Well ZH-A)
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作者 Nasser Rezavand Davood Jahani Hossein Asilian 《Open Journal of Geology》 2016年第12期1539-1552,共14页
The current paper is focused on the facies, sedimentary environment and depositional cycles study of the Middle-Late Permian sediments in the South Fars Zireh Gas Field, the subsurface section of well ZH-A. Four hundr... The current paper is focused on the facies, sedimentary environment and depositional cycles study of the Middle-Late Permian sediments in the South Fars Zireh Gas Field, the subsurface section of well ZH-A. Four hundred thin-sections obtained from cores and cuttings were examined under standard petrographic microscope. For this study research, Corel Draw X6, Corel Photo-Paint, DN2 Microscopy Image Processing System, Scope Photo, Autodesk Map, Geocalc and Auto Cad 2014 were utilized. Based on microfacies analysis and significant founa and flora, fourteen major facies in four facies associations comprising tidal flat (A), lagoon (B), shoal (C) and open marine (D) identified in the well ZH-A. This formation was deposited in inner part of a homoclinal ramp. Based on depositional cycles, seven main 3rd order sequences were revealed in the Well ZH-A. The ooid grainstone facies with interparticle and oomoldic porosity has high reservoir potential. The diagenetic processes like dolomitization and dissolution have significant effect in the reservoir quality. Based on research results, a major framework can be weaved and used to correlate reservoir layering. 展开更多
关键词 middle-late Permian Sediments Depositional Cycles Homoclinal Ramp
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