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新电脑 2001年第3期 86-86页

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关键词：屏幕保护程序钟表计时仪器 clockwise

Structural architecture of Neoproterozoic rifting depression groups in the Tarim Basin and their formation dynamics

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Science China Earth Sciences 2019年第3期62卷 529-549页

作者： Bizhu HE Cunli JIAO Taizhu HUANG Xingui ZHOU Zhihui CAI Zicheng CAO Zhongzheng JIANG Junwen CUI Zhuoyin YU Weiwei CHEN Ruohan LIU Xiaorui YUN Guangming HAO Institute of Geology Chinese Academy of Geological Sciences Exploration and Production Research Institute of SINOPEC Institute of Northwestern Petroleum Subsidiary of SINOPEC Oil and Gas Investigation Centre of China Geological Survey

The Tarim Basin is the largest, oil-bearing, superimposed basin in the northwest of China. The evolution and tectonic properties of the initial Tarim Basin have been hotly disputed and remain enigmatic. The Neoproterozoic basin is covered by a vast desert and a huge-thickness of sedimentary strata, has experienced multiple tectonic movements, had a low signal to noise ratios(SNRs) of deep seismic reflection data, all of which have posed critical obstacles to research. We analysed four field outcrops, 18 wells distributed throughout the basin, 27 reprocessed seismic reflection profiles with higher SNRs across the basin and many ancillary local 2D and 3D profiles and aeromagnetic data. We found about 20 normal fault-controlled rifting depressions of the Cryogenian and Ediacaran scattered throughout the basin, which developed on the Precambrian metamorphic and crystalline basement. The structural framework is clearly different from that of the overlying Phanerozoic. The rifting depressions consist of mainly half grabens, symmetrical troughs and horst-grabens. From the northeast to southwest of the basin,they are divided into three rifting depression groups with the WNW, ENE, and NW-trends that are mainly controlled by normal faults. The maximum thicknesses of the strata are up to 4100 m. From the Cryogenian to Ediacaran, most of the main inherited faults to active and eventually ceased at the end of the Ediacaran or Early Cambrian, while subsidence centres appeared and migrated eastward along the faults. They revealed that the different parts of the Tarim continental block were in NNE-SSWoriented and NNW-SSE-oriented extensional paleo-stress fields(relative to the present) during the Neoproterozoic, and were accompanied by clockwise shearing. According to the analysis of the activities of syn-sedimentary faults, filling sediments,magmatic events, and coordination with aeromagnetic anomalies, the tectonic properties of the fault depressions are different and are primari

关键词： Rifting depression groups Normal faults Extensional and clockwise shearing Cryogenian and Ediacaran Continental rift and intra-continental fault-controlled basin Tarim Basin

The symmetry of diffusions and the circulations of their projection processes

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Science China Mathematics 1998年第10期41卷 1017-1022页

作者：龚光鲁钱敏平 1. Department of Applied Mathematics Tsinghua University 100084 Beijing China 2. Department of Probability and Statistics Peking University 100871 Heijing China

The projection process along a simple closed smooth curve of a nonexplosive diffusion process on a cornplete Riemannian manifold is defined in probabilistic way. The winding numbers of the pmjection process are clockwise and counterclockwise given. The symmetry of the diffusion process is shown to be equivalent to that for any closed smooth curve. the long time average winding numbers of the projection process in two different directions are equal.

关键词： symmetry projection process clockwise circulation count erclockwise circulation.

Research on the dynamics of the South China Sea opening:Evidence from analogue modeling

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Science China Earth Sciences 2006年第10期49卷 1053-1069页

作者： SUN Zhen1,2, ZHOU Di1, ZHONG Zhihong3, XIA Bin2, QIU Xuelin1, ZENG Zuoxun4 & JIANG Jianqun5 1. CAS Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China 2. CAS Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 3. Department of Technology, Shenzhen Branch of CNOOC, Guangzhou 510240, China 4. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 5. Hainan Oil & Gas Exploration Company, Liaohe Oilfield PetroChina, Panjin 124010, China 1. CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. CAS Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 3. Department of Technology Shenzhen Branch of CNOOC Guangzhou 510240 China 4. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 5. Hainan Oil & Gas Exploration Company Liaohe Oilfield PetroChina Panjin 124010 China

Independent of Indochina extrusion, the South China Sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 32 to 26 Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From 24 Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South China Sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South China Sea evolu- tion. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-2 depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South China Sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground), while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South China Sea might be caused by slab pull from the proto South China Sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

关键词： South China Sea, rifting and drifting, clockwise rotation, analogue modeling, rigid massifs.

Evaluation of cyclorotation during femtosecond laser-assisted cataract surgery performed by using LenSx femtosecond laser

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山东大学耳鼻喉眼学报 2020年第2期34卷 47-52页

作者： Shazia BANO Shaowei LI Chang LIU Xinxin LI Saeed ALI Department of Ophthalmology Aier School of OphthalmologyCentral South UniversityChangsha 410083HunanChina Department of Ophthalmology Beijing Aier-Intech Eye HospitalBeijing 100021China

Objectives To evaluate degrees and percentages of cyclorotation in Chinese patients during femtosecond laser assisted cataract surgery performed by using LenSx femtosecond laser platform and to further sub-analyze bilateral cases to assess the congruency between both eyes. Methods This was a single-centre retrospective study(Beijing AIER-Intec Eye Hospital, Beijing, China) in which the records of 330 eyes of 274 patients who underwent femtosecond laser-assisted cataract surgery in 1 or two eyes(with placement of posterior chamber IOL) between May 2017 and July 2019 by using femtosecond laser platform(LenSx) were *** Femtosecond Laser(Alcon Laboratories, Inc, Fort Worth, Texas, USA) was used to carry out corneal incisions, anterior capsulotomies and lens fragmentation in this procedure. All the patients were marked on corneal limbus(at 3 and 9 o’clock positions) by using sterile skin marker(***) while sitting upright preoperatively. Percentages of cyclorotation were calculated. Absolutes values were taken for all calculations. The cyclorotation data was tested to determine whether it followed a normal distribution. Descriptive statistics were applied to calculate percentile values of cyclorotation which is presented as(M [P25;P75]). Results This retrospective study evaluated 330 eyes of 274 Chinese patients who had femtosecond laser-assisted cataract surgery using the femtosecond laser platform. Of the 330 eyes, there were 90 eyes(27.27%) that did not show cyclorotation. Out of 330 eyes that were analyzed, 72.72%(240 eyes) exhibited cyclorotation. The median value of cyclorotation was 3.0[0.0;5.0](ranged between 0 to 19 degrees). Of the 330 eyes, there were 90 eyes(27.27%) that did not show cyclorotation. Overall anticlockwise rotation(172 eyes, 52.12%) was more common than clockwise rotation(68 eyes, 20.60%).The total numbers of right and left eyes were 169 and 161 respectively. In terms of laterality, 43.78% of right eyes(74 eyes out of 169) and

关键词： Femtosecond Laser Cataract Cyclorotation clockwise rotation Anticlockwise rotation