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Injuries Associated with Auto-Tricycle Crashes in an African City: Incidence and Pattern
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作者 Augustus Nii Kwame Okleme David Anyitey-Kokor +3 位作者 Dominic Konadu-Yeboah Adam Gyedu Kwabena Agbedinu Johathan Boakye 《Open Journal of Orthopedics》 2024年第5期229-246,共18页
Purpose: The aim of this study was to determine the incidence and pattern of injuries resulting from auto-tricycle crashes among patients in a tertiary referral centre in Ghana. Methods: Data were retrospectively extr... Purpose: The aim of this study was to determine the incidence and pattern of injuries resulting from auto-tricycle crashes among patients in a tertiary referral centre in Ghana. Methods: Data were retrospectively extracted from hospital records of patients who got involved in auto-tricycle crashes and presented to the Accident and Emergency Centre of the Komfo Anokye Teaching Hospital (KATH), over a one-year period using a structured questionnaire. The gathered data were then entered into an electronic database and then analysed with SPSS version 20.0. Results: The incidence of injury following auto-tricycle crashes over the one-year period was 5.9% (95% CI: 4.9% - 7.0%) with a case fatality rate (FR) of 3.8% (95% CI: 1.3% - 8.7%). All the mortalities resulted from head and neck injuries and none of the patients involved wore a crash helmet. Only 5% of those studied wore crash helmets and were all drivers. Closed fractures accounted for 58% of the injuries, followed by open fractures, 28%. The most commonly fractured bones were the tibia/fibula, followed by the femur and then radius/ulna. The most common mechanism of injury was auto-tricycle toppling over (29%). Passengers were the most injured (48%), followed by drivers (37%) and pedestrians (15%). Most (72%) injuries among participants involved a single body part. On the injury severity scale, most (61%) of patients had minor trauma and 38% had major trauma. Conclusion: Auto-tricycle crashes account for 5.9% of injuries at the study site with a case fatality rate of 3.8%. Passengers had a higher injury rate (48%) than drivers (37%). Fractures of the tibia/fibula were most commonly associated with auto-tricycle crashes. Injuries to the head and neck were responsible for the deaths in the study participants and non-use of a crash helmet was associated with mortalities. 展开更多
关键词 Auto-tricycle KNOCK-DOWN RICKSHAW Road Traffic Crashes
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Effi cacy of tricyclic antidepressants in irritable bowel syndrome:A meta-analysis 被引量:22
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作者 Roja Rahimi Shekoufeh Nikfar +1 位作者 Ali Rezaie Mohammad Abdollahi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第13期1548-1553,共6页
We aimed to evaluate the efficacy of tricyclic antidepressants(TCAs) as a therapeutic option for irritable bowel syndrome(IBS) through meta-analysis of randomized controlled trials.For the years 1966 until September 2... We aimed to evaluate the efficacy of tricyclic antidepressants(TCAs) as a therapeutic option for irritable bowel syndrome(IBS) through meta-analysis of randomized controlled trials.For the years 1966 until September 2008,PubMed,Scopus,Web of Science,and Cochrane Central Register of Controlled Trials were searched for double-blind,placebo-controlled trials investigating the effi cacy of TCAs in the management of IBS.Seven randomized,placebo-controlled clinical trials met our criteria and were included in the metaanalysis.TCAs used in the treatment arm of these trials included amitriptyline,imipramine,desipramine,doxepin and trimipramine.The pooled relative risk for clinical improvement with TCA therapy was 1.93(95% CI:1.44 to 2.6,P<0.0001).Effect size of TCAs versus placebo for mean change in abdominal pain score among the two studies was -44.15(95% CI:-53.27 to -35.04,P<0.0001).It is concluded that low dose TCAs exhibit clinically and statistically signifi cant control of IBS symptoms. 展开更多
关键词 Systematic review META-ANALYSIS tricyclic antidepressants Irritable bowel syndrome EFFICACY Clinical response Abdominal pain
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Tricyclic Sesquiterpene from Laurencia Majuscula 被引量:2
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作者 XU Xiao Hua ZENG Long Mei SU Jing Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第2期84-86,共3页
TricyclicSesquiterpenefromLaurenciaMajuscula*XUXiao-Hua,ZENGLong-MeiandSUJing-Yu**(DepartmentofChemistry,Zho... TricyclicSesquiterpenefromLaurenciaMajuscula*XUXiao-Hua,ZENGLong-MeiandSUJing-Yu**(DepartmentofChemistry,ZhongshanUniversity,... 展开更多
关键词 tricyclic sesquiterpene Laurencia majuscula TERPENOID Majusin
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Study on the Total Synthesis of Et 743 and its Analogues: Synthesis of a Tricyclic Intermediate and its 11-Epimer 被引量:1
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作者 Ye Feng TANG, Zhan Zhu LIU, Shi Zhi CHENInstitute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union MedicalCollege, Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期996-998,共3页
The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but no... The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but not when BOP-C1 used in the same reaction. The stereochemistry of both isomers was confirmed on basis of the 1H NMR and NOE-difference spectra. 展开更多
关键词 Et 743 tricyclic compound synthesis stereochemistry.
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An Efficient Synthesis of Ethyl 7-Chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quinoline-3-carboxylate as Intermediate of the Prulifloxacin Containing Tricyclic Fluoroquinolone 被引量:1
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作者 Shu Tao MA Hong Xiang LOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期714-716,共3页
Novel ethyl 7-chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quino- line-3-carboxylate 2 was prepared from 3-chloro-4-fluoroaniline in eight steps. It can be used as a new intermediate for the synth... Novel ethyl 7-chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quino- line-3-carboxylate 2 was prepared from 3-chloro-4-fluoroaniline in eight steps. It can be used as a new intermediate for the synthesis of tricyclic fluoroquinolones. 展开更多
关键词 Synthesis tricyclic fluoroquinolone.
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Geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Basin,Nigeria 被引量:2
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作者 Abiodun B.Ogbesejana Oluwasesan M.Bello +3 位作者 Tijjani Ali Uduma A.Uduma Kamaluddeen S.Kabo Oluwadurotimi O.Akintade 《Acta Geochimica》 EI CAS CSCD 2021年第2期184-198,共15页
Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock extracts.However,they have not been reported in the Offshore Niger Delta Basin,Nigeria.Thus,the present study investigated the... Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock extracts.However,they have not been reported in the Offshore Niger Delta Basin,Nigeria.Thus,the present study investigated the geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Bain,Nigeria with gas chromatography-mass spectrometry(GC-MS).The total relative abundances of tricyclic terpanes,C_(19)TT-C_(21)TT,and C_(23) TT in the rock samples ranged from 82.50 to 96.37%,50.08 to 74.17%,and 25.83 to 49.92%,respectively.These values showed the source rocks were formed from a mixed origin(terrestrial and marine).Among the tricyclic and tetracyclic terpanes identified in the rock extracts,the conventional(C_(20)TT,C_(23)TT,C_(24)TT,C_(24)TeT)and recent(Y1,X1,Z1)were more prominent than all others,indicating mixed input of terrigenous and marine organic matter.The C_(24)TT/C_(23)TT,C_(24)TeT/(C_(24)TeT+C_(26)TT),C_(19)TT/C_(23)TT,C_(20)TT/C_(23)TT,C_(25)TT/C_(24)TeT,C_(25)TT/C_(26)TT,C_(19)TT/C_(20)TT,C_(24)TeT/C_(26)TT,Z1/(Z1+C_(24)TT),and Y1/(Y1+C_(24)TT)in the rock samples range from 0.33 to 1.30,0.76 to 0.90,0.18 to 0.73,0.34 to 1.05,0.33 to 1.74,0.30 to 1.39,0.31 to0.89,1.66 to 4.33,0.36 to 0.83,and 0.34 to 0.79,respectively.These values further showed that the rock samples were formed from mixed input of terrigenous and marine organic matter and deposited under oxic to suboxic conditions in lacustrine-fluvial/deltaic environments.Also,the C_(24)TeT/C_(20)-26TT,C_(24)TeT/C_(30)HOP,and C_(23)TT/C_(30)HOP ranged from 0.16 to 0.45,0.02 to 0.42,and 0.01 to 0.48,respectively.This range of values suggests that source rocks were within immature to early mature stage.Thus,this study showed that tricyclic and tetracyclic terpanes were effective in determining the origin,depositional environments,and thermal maturity of source rocks in the Niger Delta Basin,Nigeria. 展开更多
关键词 tricyclic terpanes Tetracyclic terpanes Source rocks Niger delta Gas chromatography-mass spectrometry(GC-MS)
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Crystal Structure of a Tricyclic Compound C_(20)H)(28)O_6 Obtained through IMDA Reaction
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作者 CHAI Ji-Jie HE Cun-Heng +3 位作者 LI Ming ZHANG Lu-YanCHEN Shi-Zhi YANG Wen-Qian HUANG Liang(Institute of Materia Medica, Chinese Academy of Medical Sciences & PekingUnion Medical College, No. 1 Xian Nong Tan Street, Beijing 100050) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第5期345-348,共4页
The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2),... The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2), b=11-.863 (3 ), c =29. 59 (1) , β= 101. 02(5)°, V=3894. 246, Dc=1.2413 g/cm3, Z=8, F(000)=1568, Mr= 364. 00 R=0.055, R2=0. 055, μ= 535 cm-1, S(GOF) =0. 571. Theconfiguration of C2a-H in the title compound was found to be contrary to what wasexpected and a possible mechanism of reaction was proposed. 展开更多
关键词 IMDA REACTION CRYSTAL structure tricyclic COMPOUND
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The Inertia Indexes of One Special Kind of Tricyclic Graphs
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作者 Haicheng Ma Chengling Xie 《Applied Mathematics》 2019年第1期11-18,共8页
Let G be a graph and A=(aij)n×n be the adjacency matrix of G, the eigenvalues of A are said to be the eigenvalues of the graph G, and to form the spectrum of this graph. The numbers of positive, negative and zero... Let G be a graph and A=(aij)n×n be the adjacency matrix of G, the eigenvalues of A are said to be the eigenvalues of the graph G, and to form the spectrum of this graph. The numbers of positive, negative and zero eigenvalues in the spectrum of the graph G are called positive and negative inertia indexes and nullity of the graph G, are denoted by p(G), n(G), η(G), respectively, and are collectively called inertia indexes of the graph G. The inertia indexes have many important applications in chemistry and mathematics. The purpose of the research of this paper is to calculate the inertia indexes of one special kind of tricyclic graphs. A new calculation method of the inertia indexes of this tricyclic graphs with large vertices is given, and the inertia indexes of this tricyclic graphs with fewer vertices can be calculated by Matlab. 展开更多
关键词 tricyclic GRAPHS Positive INERTIA INDEX Negative INERTIA INDEX NULLITY
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Study on the Total Synthesis of Hainanolide-Construction of Tricyclic Intermediate(I)
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作者 Lu Yan ZHANG Shi Zhi CHEN +3 位作者 Dong WEI Liang HUANG Ji Jie CHAI Cun Heng HE(Institute of Materia Medica Chinese Academy of Medical Sciences.Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期892-893,共2页
Tricyclic compounds (4b-endo) and (4b-exo) are synthesized as the plausible intermediates of the total synhthesis of hainanolide by Lewis acid catalyzed intramolecular DielsAlder (IMDA) reaction.
关键词 SYNTHESIS TOTAL INTERMEDIATE tricyclic Construction Hainanolide
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Study on the Total Synthesis of Hainanolide (Ⅱ)──An Unexpected Hydroperoxide Containing Tricyclic Skeleton
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作者 Lu Yan ZHANG Wen Qian YANG +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing,100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第1期15-16,共2页
An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed b... An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed. 展开更多
关键词 ppm An Unexpected Hydroperoxide Containing tricyclic Skeleton Study on the Total Synthesis of Hainanolide
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Mass asymmetry and tricyclic wobble motion assessment using automated launch video analysis
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作者 Ryan DECKER Joseph DONINI +2 位作者 William GARDNER Jobin JOHN Walter KOENIG 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第2期113-116,共4页
This paper describes an approach to identify epicyclic and tricyclic motion during projectile flight caused by mass asymmetries in spinstabilized projectiles. Flight video was captured following projectile launch of s... This paper describes an approach to identify epicyclic and tricyclic motion during projectile flight caused by mass asymmetries in spinstabilized projectiles. Flight video was captured following projectile launch of several M110A2E1 155 mm artillery projectiles. These videos were then analyzed using the automated flight video analysis method to attain their initial position and orientation histories.Examination of the pitch and yaw histories clearly indicates that in addition to epicyclic motion's nutation and precession oscillations, an even faster wobble amplitude is present during each spin revolution, even though some of the amplitudes of the oscillation are smaller than 0.02 degree.The results are compared to a sequence of shots where little appreciable mass asymmetries were present, and only nutation and precession frequencies are predominantly apparent in the motion history results. Magnitudes of the wobble motion are estimated and compared to product of inertia measurements of the asymmetric projectiles. 展开更多
关键词 弹丸质量 视频分析 摆动运动 不对称性 自动启动 三环 评估 行星运动
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Theoretical calculation and experimental studies of rare tricyclic nucleoside derivative
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作者 ZHAOHongwei DOUDaying WANGWenfeng WUGuozhong YAOSide 《辐射研究与辐射工艺学报》 CAS CSCD 北大核心 2005年第2期76-76,共1页
关键词 三环核苷衍生物 激光光解 脉冲辐射分解 电离势能 辐射化学
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库车坳陷侏罗系腐殖煤三环萜烷异常分布原因探究 被引量:2
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作者 张敏 项威 +1 位作者 张文俊 李洪波 《长江大学学报(自然科学版)》 2024年第2期23-35,共13页
三环萜烷类化合物普遍存在于各类原油与烃源岩中,具有较强的抗生物降解能力及环境指相意义。通过地球化学分析手段对库车坳陷10个腐殖煤样品进行分子化合物研究,发现库车河剖面与卡普沙良河剖面腐殖煤三环萜烷的分布模式差异迥然,库车... 三环萜烷类化合物普遍存在于各类原油与烃源岩中,具有较强的抗生物降解能力及环境指相意义。通过地球化学分析手段对库车坳陷10个腐殖煤样品进行分子化合物研究,发现库车河剖面与卡普沙良河剖面腐殖煤三环萜烷的分布模式差异迥然,库车河剖面主要分布模式为“C_(19)下降型”(C_(19)>C_(20)>C_(21)<C_(23)),卡普沙良河剖面主要分布模式为“C_(21)主峰型”(C_(19)<C_(20)<C_(21)>C_(23))与“C_(23)主峰型”(C_(19)<C_(20)<C_(21)<C_(23))。研究还发现库车河剖面与卡普沙良河剖面腐殖煤成熟度存在明显差异,成熟度的增长会引起三环萜烷的总量上升以及单个三环萜烷化合物绝对量的变化,但在一定成熟度范围内(镜质体反射率(R o)<1.5%),三环萜烷分布模式不发生改变。卡普沙良河剖面腐殖煤三环萜烷分布模式的变化主要受还原环境以及海侵作用引起的细菌等微生物对高等植物的生物改造及低等水生生物输入的影响。 展开更多
关键词 三环萜烷 沉积环境 分布模式 库车坳陷
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原油中C_(19-49)长链三环萜烷系列及其地球化学意义——以柴达木盆地西部英西地区原油为例
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作者 包建平 朱翠山 +3 位作者 杨茜 陈琰 周飞 张静 《沉积学报》 CAS CSCD 北大核心 2024年第5期1765-1783,共19页
【目的】为了确定柴达木盆地西部英西地区古近系深部储层(E)原油的热演化程度和成因类型,【方法】利用色谱—质谱(GC-MS)和色谱—质谱—质谱(GC-MS-MS)技术,对其中的各类生物标志物、烷基菲和金刚烷类化合物的分布与组成特征进行了系统... 【目的】为了确定柴达木盆地西部英西地区古近系深部储层(E)原油的热演化程度和成因类型,【方法】利用色谱—质谱(GC-MS)和色谱—质谱—质谱(GC-MS-MS)技术,对其中的各类生物标志物、烷基菲和金刚烷类化合物的分布与组成特征进行了系统分析。【结果与讨论】分析结果表明该地区原油中正构烷烃系列均具有明显的偶碳优势,Pr/Ph比值低(<0.60),Ph/nC_(18)比值高(>1.30),伽马蜡烷含量高,伽马蜡烷指数介于0.90~1.36,属于典型咸水湖相原油,这与研究区古近纪的沉积特征一致。但依据不同原油中长链三环萜烷系列的分布与组成特征,可将他们分成两类:一类原油中C_(19-49)长链三环萜烷系列异常丰富,C_(19-30)TT/C_(27-35)H比值大于1.60,C_(23)TT/C_(30)H>1.40,并伴随有高甾藿比(>4.50)和高β-胡萝烷/nC_(37)比值(>3.20),表明藻类是其主要原始生烃母质;另一类原油中C_(19-30)长链三环萜烷系列含量中等,C_(19-30)TT/C_(27-35)H比值小于0.50,C_(23)TT/C_(30)H<0.55,其甾藿比相对较低(<2.0)、β-胡萝卜烷含量中等,β-胡萝烷/nC_(37)比值小于1.50,可见此类原油中藻类的贡献明显低于前一类原油。对比它们的甾、萜烷和金刚烷类化合物成熟度参数,发现这两组原油的成熟度相近,其对应的R_(o)值介于1.1%~1.3%,即它们形成于生油高峰之后、凝析油气形成以前这一演化阶段。【结论】影响研究区原油中长链三环萜烷系列相对丰度的主要因素是原始生烃母质,而非成熟度,因而它在研究区具有指示原油成因类型的作用,在后续油气勘探中应重点关注。 展开更多
关键词 藿烷系列 C_(19-49)长链三环萜烷系列 伽马蜡烷 β-胡萝卜烷 甾藿比 原油 英西地区 柴达木盆地西部
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基于聚合松香和聚丙烯分子模拟的纳米纤维的制备与表征 被引量:1
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作者 王文刚 齐浩彤 +2 位作者 钱裕洁 侯秀良 徐荷澜 《应用化工》 CAS CSCD 北大核心 2024年第4期763-768,共6页
通过材料计算软件(Materials Studio)对高聚物聚丙烯和玻璃态三环二萜小分子聚合松香的共混过程进行分子动力学模拟,得到不同共混条件下,聚丙烯与聚合松香的Flory-Huggins相互作用参数和径向分布函数的变化趋势。在此基础上,进行了聚丙... 通过材料计算软件(Materials Studio)对高聚物聚丙烯和玻璃态三环二萜小分子聚合松香的共混过程进行分子动力学模拟,得到不同共混条件下,聚丙烯与聚合松香的Flory-Huggins相互作用参数和径向分布函数的变化趋势。在此基础上,进行了聚丙烯与聚合松香的熔融共混,对共混物的微观结构、热学性能和表面形貌进行表征,同时探究了共混物的可纺性能。结果表明:聚丙烯和聚合松香具有良好的相容性,两者可以通过熔融纺丝的方法制备出最细可达50 nm的聚丙烯纳米纤维。 展开更多
关键词 聚丙烯 三环二萜 分子模拟 熔融纺丝 纳米纤维
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中非Muglad盆地晚白垩世海侵及其对油气勘探的意义
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作者 肖洪 李美俊 +3 位作者 程顶胜 刘计国 李晋 邢向荣 《地学前缘》 EI CAS CSCD 北大核心 2024年第3期352-359,共8页
晚白垩世全球大规模海侵被认为仅淹没了非洲大陆北部地区,而位于非洲中部的Muglad盆地则未遭受海侵的影响,且盆地内仅发育一套富有机质的烃源岩,即下白垩统Abu Gabra组湖相泥岩。本次研究采集了下白垩统Abu Gabra组湖相泥岩和上白垩统Da... 晚白垩世全球大规模海侵被认为仅淹没了非洲大陆北部地区,而位于非洲中部的Muglad盆地则未遭受海侵的影响,且盆地内仅发育一套富有机质的烃源岩,即下白垩统Abu Gabra组湖相泥岩。本次研究采集了下白垩统Abu Gabra组湖相泥岩和上白垩统Darfur群泥岩样品,在上白垩统Darfur群泥岩中检测到完全不同于下白垩统Abu Gabra组湖相泥岩的甲藻甾烷和三环萜烷组成,主要表现为高丰度的甲藻甾烷异构体和C_(23)三环萜烷丰度优势,认为其是海侵作用的产物。依据分析结果,本文首次提出上白垩统Darfur群沉积期可能受到新特提斯洋海水的影响,进一步揭示了晚白垩世全球海侵在非洲大陆的海水淹没范围已抵达中非大陆Muglad盆地。此外,上白垩统Darfur群海相富有机质泥岩的存在,揭示研究区不仅发育下白垩统Abu Gabra组湖相烃源岩,还发育一套潜在的海相烃源岩。而K-1井海相原油的发现进一步证实了上白垩统Darfur群海相烃源岩的生烃潜力,海相原油可能是研究区未来油气勘探的新领域。 展开更多
关键词 海侵 晚白垩世 分子标志化合物 甲藻甾烷 三环萜烷 海相原油
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鄂尔多斯盆地上古生界煤系烃源岩三环萜烷成因探讨
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作者 林舒敏 张敏 李洪波 《沉积学报》 CAS CSCD 北大核心 2024年第4期1433-1446,共14页
【目的】鄂尔多斯盆地煤系烃源岩发育,其饱和烃中三环萜烷含量丰富,但其三环萜烷分布模式在研究区表现出较大的差异性,因此探讨其差异性的主控因素具有重要意义。【方法】利用气相色谱和色谱—质谱分析技术,对鄂尔多斯盆地上古生界26个... 【目的】鄂尔多斯盆地煤系烃源岩发育,其饱和烃中三环萜烷含量丰富,但其三环萜烷分布模式在研究区表现出较大的差异性,因此探讨其差异性的主控因素具有重要意义。【方法】利用气相色谱和色谱—质谱分析技术,对鄂尔多斯盆地上古生界26个煤系烃源岩样品饱和烃进行了详细地剖析。【结果】根据三环萜烷(TT)的分布特征将研究区烃源岩样品划分为三种不同类型的分布模式。Ⅰ类烃源岩以C_(19)TT为主峰,C_(19)TT、C_(20)TT、C_(21)TT含量逐渐减小的变化趋势,同时该类样品中Pr/Ph比值高,介于1.19~3.84,平均值为2.99、C_(24)四环萜烷含量也较丰富,C_(24)四环萜烷/C_(26)TT比值介于2.39~32.54,平均值为9.80、C_(28)三环萜烷和C_(29)三环萜烷缺失,这类样品主要是腐殖煤和炭质泥岩,揭示出湖沼相沉积环境之特征;与之相反的Ⅱ类烃源岩的三环萜烷以C_(23)TT为主峰,C_(19)TT、C_(20)TT、C_(21)TT含量是逐渐增大的,而Pr/Ph比值低,比值主要介于0.34~0.90,平均值为0.61、C_(24)四环萜烷含量不丰富,C_(24)四环萜烷/C_(26)TT比值主要介于0.42~0.77,平均值为0.54、C_(28)三环萜烷和C_(29)三环萜烷含量丰富,这类样品除了煤系泥岩之外还有腐殖煤和炭质泥岩,其沉积环境与Ⅰ类烃源岩迥然不同;Ⅲ类烃源岩的三环萜烷分布介于Ⅰ类和Ⅱ类烃源岩之间,一方面三环萜烷的主峰碳为C_(23)TT,另一方面C_(19)TT、C_(20)TT、C_(21)TT相对含量又依次降低并呈阶梯状分布的特征,此外Pr/Ph比值为2.07、C_(24)四环萜烷/C_(26)TT比值为3.53,两者均介于Ⅰ类烃源岩和Ⅱ类烃源岩之间。【结论】随着烃源岩热演化程度的增加,三环萜烷的总量展示了逐渐增大的变化趋势,但不同类型烃源岩的三环萜烷分布模式并没有发生明显变化,说明研究区煤系烃源岩三环萜烷的不同分布模式受有机质热演化程度影响较小,而主要受控于沉积环境和母质类型。 展开更多
关键词 三环萜烷 主控因素 沉积环境 煤系烃源岩 鄂尔多斯盆地
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三圈图的(2,2)-可选性的证明
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作者 马双 吴廷增 《青岛大学学报(自然科学版)》 CAS 2024年第3期1-8,共8页
每一个图是(2,2)-可选的猜想迄今未被解决,为了推动(2,2)-可选猜想的证明,利用积和指数的方法证明了所有三圈图是(2,2)-可选的。
关键词 列表分配 总赋权可选性 积和指数 三圈图
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The role of selective serotonin reuptake inhibitors and tricyclic antidepressants in addressing reduction of Meniere's disease burden:A scoping review
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作者 Alexander A.Missner Mana Sheykhsoltan +1 位作者 Amir Hakimi Michael Hoa 《World Journal of Otorhinolaryngology-Head and Neck Surgery》 CAS CSCD 2024年第3期206-212,共7页
Objective:To assess the effect of selective serotonin reuptake inhibitors(SSRIs)and tricyclic antidepressants(TCAs)in reducing vertigo,tinnitus,and hearing loss among patients with Meniere's disease(MD).Data Sourc... Objective:To assess the effect of selective serotonin reuptake inhibitors(SSRIs)and tricyclic antidepressants(TCAs)in reducing vertigo,tinnitus,and hearing loss among patients with Meniere's disease(MD).Data Sources:The following databases were utilized in this scoping review:Ovid Medline,PubMed-NCBI,CINAHL,Cochrane Library,Web of Science,and Clinicaltrials.gov.Method:Studies were identified through the following search phrases:"serotonin specific reuptake inhibitors"OR"tricyclic antidepressants"AND"Meniere's disease."References from included manuscripts were examined for possible inclusion of additional studies.Results:The literature search yielded 23 results,which were screened by three independent reviewers.Seventeen studies and three duplicates were excluded.An examination of references from the included studies yielded two additional publications.A total of four published studies assessing SSRIs and TCAs among 147 patients with MD were ultimately included.Four studies described significant reductions in vertigo attack frequency among patients treated with either SSRIs or TCAs compared to their pretreatment baseline.Three studies assessed the drugs'effects on hearing,of which none found a significant difference among patients treated with SSRIs or TCAs.One study found a significant decrease in patient-reported tinnitus following treatment with TCAs or SSRIs compared to their pretreatment baseline.Conclusions:Data exploring SSRIs and TCAs among patients with MD suggests that these medications may reduce the frequency of tinnitus and vertigo,although there was significant heterogeneity in outcome reporting.There remains a need for larger-scale prospective studies that emphasize objective data to evaluate their effective-ness in reducing common MD symptoms. 展开更多
关键词 aural fullness clinical trials Meniere's disease scoping review sensorineural hearing loss serotonin specific reuptake inhibitors tricyclic antidepressants VERTIGO
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三圈图中有关广义Somber指数的研究
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作者 董邢悦 耿显亚 《洛阳师范学院学报》 2024年第8期8-12,共5页
为了进一步研究表征分子图、预测化合物的生物活性以及建立分子结构和性质之间的关系,对三圈图G中广义Somber指数的分子图进行了研究,确定了三圈图中广义Somber指数的极值.结果发现,具有n个顶点的基三圈图集合上,在τ_(15)^(n)(1,1,1,1... 为了进一步研究表征分子图、预测化合物的生物活性以及建立分子结构和性质之间的关系,对三圈图G中广义Somber指数的分子图进行了研究,确定了三圈图中广义Somber指数的极值.结果发现,具有n个顶点的基三圈图集合上,在τ_(15)^(n)(1,1,1,1,1)时Somber指数值最小. 展开更多
关键词 广义Somber指数 三圈图 分子图 极值
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