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Evolution of Cenozoic sedimentary architecture in Central and Southern South China Sea basins

Journal of Palaeogeography 2024年第1期13卷 35-53页

作者： Wu Tang xiao-Jun Xie yi-Bo Wang Lian-Qiao Xiong Jia Guo Xin Li China National Offshore Oil Corporation Research Institute Beijing 100028China

The Central and Southern South China Sea(CSSCS) has a complex tectonic dynamic background and abundant oil and gas resources, which has always been a hot topic of academic and industrial ***, systematic analyses are still lacking regarding its sediment filling structure and evolution, mostly due to limited borehole penetration and poor quality of seismic reflection data for deeply buried sequences. No consensus has been reached yet on the sedimentary infilling processes, which impeded the reconstruction of the palaeogeography of Southeast Asia and the oil-and-gas exploration undertakings. Here, we illustrate the Cenozoic sedimentary evolution of the CSSCS region by synthesizing relevant data from previous literature and our own observations and displaying the evolution of depositional systems in sequential reconstructions. Besides, the controlling factors of preferred sedimentary scenarios in the CSSCS incorporate the latest interpretations of the spreading of South China Sea(SCS) as well as the demise of the hypothetical Proto-South China Sea(PSCS). The results show that there are three types of sedimentary basins in the CSSCS(foreland,strike-slip, and rift basins) with different sedimentary filling structures. The foreland basins formed a depositional pattern of ‘transition from deep water to shallow water environments', dominated by deep-water depositional systems which were formed before the Early Oligocene with submarine fans developed. Later,the foreland basins were gradually dominated by shallow-water depositional systems with deltas and shallow marine facies. The strike-slip basins showed the depositional architecture of ‘transition from lake to marine environments', i.e. the basins were dominated by lacustrine deposits during the Eocene and evolved into the marine depositional environment since Oligocene with delta developed in the western part of the basin. The depositional evolution of rift basins illustrated the characteristics of 'transiti

关键词： Central and Southern South China Sea Sedimentary filling Main controlling factors Proto-South China Sea South China Sea

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The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn6Ga6S16（Ae = Ca, Sr）

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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang shao-Min Pei Wen-Fa Chen Bin-Wen Liu xiao-Ming Jiang Guo-Cong Guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Physical Science and Technology Shanghai Tech University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Non-centrosymmetric（NCS） structure is an indispensable prerequisite for second-order nonlinear optical（NLO） ***, the mainstream approach for designing new NCS structures still relies on chemical substitution, necessitating an urgent infusion of fresh ideas. In this work, two isomorphic sulfides AeMn6Ga6S16（Ae = Ca, 1; Sr, 2） are afforded by modifying the skeleton of centrosymmetric（CS） Mn2Ga2S5via introducing strong electropositive alkaline-earth cations. Concretely, the incorporation of Ca2+/Sr2+cations allows the elementary [MnGaS9]∞chains to reconfigure into bumpy [MnS6]-[GaS4] layers in a new engagement manner, thus enabling the conversion from CS to NCS structure. Such modifications cause not only strong second-harmonic generation（SHG） responses（～1.5 × benchmark AgGaS2@1,700 nm）, but also significantly feasible bandgaps（2.60–2.64 e V） compared to the sulfide Mn2Ga2S5（1.36 e V）, which ultimately facilitate ultrahigh laser-induced damage thresholds（4.4–6.6 × AgGaS2@1,064 nm for compounds 1 and 2）. The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

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Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI Bao-ping FAN Hong-yan WANG Guan-nan RAO Xi GE Weifeng shao xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

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The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao Sheng xiao-ying Zhuang Xin-yi Li Gen-Sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

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Study on the occurrence and influencing factors of gastrointestinal symptoms in hemodialysis patients with uremia

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2157-2166页

作者： Dan Yuan xiao-Qi Wang Feng shao Jing-Jing Zhou Zhong-Xin Li Department of Nephrology Beijing Luhe Hospital Affiliated to Capital Medical UniversityBeijing 101100China

BACKGROUND Gastrointestinal symptoms are common in patients with uremia undergoing hemodialysis,and these symptoms seriously affect patients'*** To assess the occurrence and factors influencing gastrointestinal symptoms in patients with uremia undergoing *** We retrospectively selected 98 patients with uremia who underwent regular hemo-dialysis treatment in the blood purification center of our hospital from December 2022 to December *** gastrointestinal symptoms and scores of each dimension were evaluated using the Gastrointestinal Symptom Grading Scale(GSRS).Patients were divided into gastrointestinal symptoms and no gastrointestinal symptom groups according to whether they had gastrointestinal *** factors that may affect gastrointestinal symptoms were identified by single-factor *** logistic regression analysis was performed to identify independent risk factors for gastrointestinal *** Gastrointestinal symptoms included indigestion,constipation,reflux,diarrhea,abdominal pain,and eating disorders,and the total average GSRS score was 1.35±*** study showed that age,number of tablets,dialysis time,glucocorticoid,parathyroid hormone(PTH),combined diabetes mellitus and C-reactive protein(CRP)were independent risk factors for gastrointestinal symptoms in patients with uremia undergoing hemodialysis,whereas body mass index(BMI),hemoglobin(Hb),and urea clearance index were independent protective factors(P<0.05).CONCLUSION Gastrointestinal symptoms are mostly mild in patients with uremia undergoing hemodialysis,most commonly including dyspepsia,eating disorders,and gastroesophageal *** independent influencing factors mainly include the BMI,age,number of pills taken,dialysis time,urea clearance index,Hb,use of glucocorticoids,and thyroid hormone ***,CRP,and diabetes are clinically related factors influencing the occurrence of gastrointestinal symptoms,and targeted prevention can be perform

关键词： Uremic hemodialysis Gastrointestinal symptoms Influencing factors Blood pressure dialysis Chronic renal failure

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Present situation of minimally invasive surgical treatment for early gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1154-1165页

作者： Chun-Yan Li yi-Feng Wang Li-Kang Luo xiao-Jun Yang The First Clinical Medical School Lanzhou UniversityLanzhou 730000Gansu ProvinceChina The First Clinical Medicine College Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina General Surgery Clinical Centre Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina The Second Department of General Surgery Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Lanzhou University People's Clinical Hospital Lanzhou 730000Gansu ProvinceChina Gansu Research Center of Prevention and Control Project for Digestive Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Gansu Key Laboratory of Molecular Diagnostics and Precision Medicine for Surgical Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

Minimally invasive surgery is a kind of surgical operation,which is performed by using professional surgical instruments and equipment to inactivate,resect,repair or reconstruct the pathological changes,deformities and wounds in human body through micro-trauma or micro-approach,in order to achieve the goal of treatment,its surgical effect is equivalent to the traditional open surgery,while avoiding the morbidity of conventional surgical *** addition,it also has the advantages of less trauma,less blood loss during operation,less psychological burden and quick recovery on patients,and these minimally invasive techniques provide unique value for the examination and treatment of gastric cancer *** minimally invasive surgical techniques have developed rapidly and offer numerous options for the treatment of early gastric cancer(EGC):endoscopic mucosal resection(EMR),underwater EMR(UEMR),endoscopic submucosal dissection(ESD),endoscopic full-thickness resection(EFTR),endoscopic submu-cosal excavation(ESE),submucosal tunnel endoscopic resection,laparoscopic and endoscopic cooperative surgery(LECS);Among them,EMR,EFTR and LECS technologies have a wide range of applications and different modific-ations have been derived from their respective surgical operations,such as band-assisted EMR(BA-EMR),conven-tional EMR(CEMR),over-the-scope clip-assisted EFTR,no-touch EFTR,the inverted LECS,closed LECS,and so *** new and improved minimally invasive surgeries are more precise,specific and effective in treating different types of EGC.

关键词： Minimally invasive surgery Early gastric cancer Endoscopic mucosal resection Endoscopic full-thickness resection Laparoscopic and endoscopic cooperative surgery

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Effect of Artificial Electric Field Surface by Wave-Driven Triboelectricity on Anti-Bioadhesion for Riser Protection

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China Ocean Engineering 2024年第3期38卷 483-490页

作者： yi Peng QIU Hong-yuan LI Yong CAI Bao-ping Javad MOSTAGHIMI ZHANGWen-jie xiao Wen-sheng College of Mechanical and Electrical Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Equipment Technology Co. Ltd.Tianjin 300450China Department of Mechanical&Industrial Engineering University of TorontoToronto ONM5S3G8Canada

Biofouling has been a persistent problem in marine riser system, resulting in energy waste and equipment damage. Inthis study, a kind of water wave-driven contact-mode flexible triboelectric nanogeneration has been prepared byusing graphene-doped PDMS as dielectric friction material. When the graphene content is 2%, the average outputvoltage can reach 46 V under the contact frequency 10 Hz. The flexible triboelectric nanogeneration encapsulationmodule is impinged by water waves to generate alternating microelectric field on the riser surface and destroy theadhesion conditions of microorganisms during the biofilm stage. In the biofouling experiments at different stages, thebiofouling area of the platymonas subcordiformis has been reduced by 53%, 62% and 61%. It provides a new ideafor effective treatment of biofouling of mussels, oysters and barnacles attached to risers.

关键词： wave-drive triboelectric nanogeneration alternating microelectric field anti-biofouling

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Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei Si Yan Zhou Sheng xiao Zhi Qin Dong Guo Yu-Hao Qin yi-Jie Wang Bo-Yuan Zhang Bai-Ting Tian Zhi-Gang xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

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Quaternary integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1360-1394页

作者： Yong WANG Mianping ZHENG Yuan LING Shuyuan XIANG Zhaogang shao Kexin ZHANG Xue KE xiao LIN Fang HAN Jian’en HAN Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Chinese Academy of Geological Sciences Beijing 100037China Institute of Geological Survey China University of GeosciencesWuhan 430074China School of Earth Sciences East China University of TechnologyNanchang 330013China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution,record the evolution process of the Quaternary regional tectonics,paleogeography,and geomorphology of the plateau,and are extremely important areas for studying the Quaternary geological events and regional environmental *** to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota,based on the differences in the lithostratigraphic units,sedimentary characteristics,landforms,and drainage systems,the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions:the Tarim region,Loess Plateau region,Qinghai-Tibet Plateau region,Yunnan-Guizhou Plateau region,and India-Ganges *** Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions:the West Kunlun-Karakorum,AltunQilian Mountains,Qaidam-Hehuang,East Kunlun-Bayan Har,Qiangtang,East Xizang-West Yunnan-West Sichuan,and Gangdise-Himalayan *** paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet *** to the lithostratigraphic sequence and its sedimentary characteristics,stratigraphic contact relationship,formation age,and evolution of the biota in each stratigraphic sub-region,the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages.(1)The inherited differential uplift stage since the Pliocene(2.6-1.8/1.5 Ma):the regional sedimentary differences were significant,and the stratigraphic distribution was limited,the alluvial-proluvial sandy conglomerate was widely developed along the piedmont,and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains.(2)The mountain range flattening stage(1.8/1.5-1.2/0.8 Ma):the erosion unconformity surfaces around the pl

关键词： Quaternary stratigraphic sedimentary

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Atmospheric Particulate Matter 2.5(PM_(2.5))Induces Cell Damage and Pruritus in Human Skin

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Biomedical and Environmental Sciences 2024年第2期37卷 216-220页

作者： HE Qiao XUE Wan Ting LI Li yi Fan LING xiao GUO Miao Miao College of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijing 100048China China Light Industry Cosmetics Key Laboratory Beijing Technology and Business UniversityBeijing 100048China Beijing Lan Divine Technology Co.LTD Beijing 100872China

With the accelerated rate of urbanization in recent years,air pollution has become an environmental problem that requires urgent resolution,almost all of the world’s population exposed to pollution on a daily *** the... 详细信息

关键词： pollution Skin Human

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