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Provenance of upper Permian-lowermost Triassic sandstones, Wutonggou low-order cycle, Bogda Mountains, NW China:implications on the unroofing history of the Eastern North Tianshan Suture

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Journal of Palaeogeography 2020年第3期9卷 314-334页

作者： dong-yu zheng Wan Yang Geology and Geophysics Program Missouri University of Science and TechnologyRollaMO 65409USA

This study investigates the provenance of sedimentary rocks in Bogda Mountains, NW China, and reconstructs the lithology and unroofing history of the Eastern North Tianshan Suture. Petrographic point counting data of sandstones and compositions of conglomerates of upper Permian-lowermost Triassic Wutonggou low-order cycle from Zhaobishan, North Tarlong, Taodonggou, and Dalongkou sections in the southern and northern foothills of Bogda Mountains were used to interpret the temporal and spatial variations of lithology of the Eastern North Tianshan Suture, which is the sediment source area. Three compositional trends were identified. A trend of upwardincreasing quartz content and granitic pebbles in Zhaobishan section suggests a change from the undissected volcanic arc, accretionary wedge and trench setting to predominantly transitional volcanic arc and subordinate accretionary wedge and trench, in the eastern part of the Eastern North Tianshan Suture. In North Tarlong and Taodonggou sections, however, the lithic content decreases and the contents of quartz and granitic pebbles increase up sections. These trends indicate that the western part of the Eastern North Tianshan Suture changed from an undissected volcanic arc to the transitional volcanic arc, accretionary wedge and trench. No clear trend in the lithic-rich sandstones of the Dalongkou section indicates that sediments were derived from the undissected volcanic arc in the Eastern North Tianshan Suture and local rift shoulders. Compositional variations of studied rocks suggest that the Eastern North Tianshan Suture was an amalgamated complex with great spatial and temporal heterogeneities in lithology and experienced persistent unroofing during late Permian-earliest Triassic. This study reconstructs a key element of the Chinese Tianshan Suture and serves as an example to understand the unroofing processes of ancient sutures.

关键词： Provenance Wutonggou low-order cycle Bogda Mountains Unroofing Eastern North Tianshan Suture NW China

Preparation of Cr_2O_3 precursors by hydrothermal reduction in the abundant Na_2CO_3 and Na_2CrO_4 solution

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International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 978-985页

作者： Guang-ye Wei Jing-kui Qu yu-dong zheng Tao Qi Qiang Guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Beijing 100190 China Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Precursors of chromium oxide （p-Cr203） were prepared by reducing hexavalent chromium in the presence of sodium carbonate solution under hydrothermal conditions. Methanal was used as the reductant, and carbon dioxide was the acidulating agent. The influences of reaction temperature, initial pressure of carbon dioxide, isothermal time and methanal coefficient on Cr（VI） reduction were investigated. Ex- perimental results showed that Cr（VI） was reduced to Cr（III） with a yield of 99%. Chemical titration, thermogravimetry （TG）, X-ray diffrac- tion （XRD） analysis, and scanning electron microscopy （SEM） were used to characterize the p-Cr203 and Cr203. The series of p-Cr203 were found to be multiphase even if they presented different colors, from gray green to lavender. After these p-Cr203 samples were calcined, the product of rhombohedral Cr203 with a purity of 99.5wt% was obtained.

关键词： chromium oxide hydrothermal reduction sodium carbonate methanal laterite ores

A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics

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Petroleum Science 2024年第1期21卷 327-342页

作者： Qian Zhang Wen-dong Wang yu-Liang Su Wei Chen zheng-dong Lei Lei Li Yong-Mao Hao Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Oil Development Branch Changqing Oilfield CompanyPetroChinaQingyang745708GansuChina PetroChina Research Institute of Petroleum Exploration&Development Beijing100083China

A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation.

关键词： Multi-scale coupled flow Stress sensitivity Shale oil Micro-scale effect Fractal theory

An Efficient Optimization Design Framework for Low-Resistance Shape of Bionic Amphibious Robot

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China Ocean Engineering 2024年第1期38卷 117-128页

作者： ZHANG Dai-yu ZHANG Man-yu WANG Zhi-dong zheng Wen-sheng LING Hong-jie HU Jun-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

To realize the low-resistance shape optimization design of amphibious robots,an efficient optimization design framework is proposed to improve the geometric deformation flexibility and optimization *** the proposed framework,the free-form deformation parametric model of the flat slender body is established and an analytical calculation method for the height constraints is *** method is introduced to carry out the high-precision resistance calculation and a constrained Kriging-based optimization method is built to improve the optimization efficiency by circularly infilling the new sample points which satisfying the ***,the shape of an amphibious robot example is optimized to get the low-resistance shape and the results demonstrate that the presented optimization design framework has the advantages of simplicity,flexibility and high efficiency.

关键词： amphibious robot optimization method free-form deformation CFD-based hydrodynamic calculation

Three anti-inflammatory polysaccharides from Lonicera japonica Thunb.:insights into the structure-function relationships

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Food Science and Human Wellness 2024年第4期13卷 2197-2207页

作者： yu Liu Hongjing dong dongxiao Sun-Waterhouse Wenwen Li Bin Zhang Jinqian yu Zhichang Qiu Zhenjia zheng Key Laboratory of Food Nutrition and Health in Universities of Shandong College of Food Science and EngineeringShandong Agricultural UniversityTai’an 271018China Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Shandong Analysis and Test CenterQilu University of Technology(Shandong Academy of Sciences)Jinan 250014China School of Chemical Sciences The University of AucklandPrivate Bag 92019New Zealand

This study demonstrates the feasibility of producing three polysaccharides(neutral LJP-1,acidic LJP-2 and acidic LJP-3)with significant in vitro and in vivo anti-inflammatory activities from the flowers of Lonicera *** three polysaccharides differed in chemical composition,molecular weight(Mw)distribution,glycosidic linkage pattern,functional groups and *** exhibited excellent protective effects(in a dose-dependent manner)in lipopolysaccharide-injured RAW264.7 macrophages and Cu SO4-damaged zebrafish via reducing NO production and inhibiting the overexpressions of inflammation-related transcription factors,inflammatory proteins and cytokines in the NF-κB/MAPK signaling *** antiinflammatory effects varied owing to their different molecular characteristics and chemical ***,LJP-2 at 400μg/m L was the most ***-2 consisted mainly of→5)-α-L-Araf(1→,→4)-α-LGalp A(1→and→2)-α-L-Rhap(1→residues with terminal T-β-***,honeysuckle flowers are good sources of anti-inflammatory polysaccharides,and precise fractionation enables the production of potent antiinflammatory agents for the development of functional foods and healthcare products.

关键词： Honeysuckle polysaccharides Fractionation Molecular characteristics Anti-inflammatory properties Structure-function relationship

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： Qing-Jun Du Hao-yu zheng Jian Hou Yong-Ge Liu Jian-Fang Sun dong Zhao State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production Research Institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided into 180 equally sized zones based on the CT scanning images, and threedimensional(3D) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. In the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. In the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

The Logarithmic Sobolev Inequality for a Submanifold in Manifolds with Nonnegative Sectional Curvature

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 487-496页

作者： Chengyang YI yu zheng School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The authors prove a sharp logarithmic Sobolev inequality which holds for compact submanifolds without boundary in Riemannian manifolds with nonnegative sectional curvature of arbitrary dimension and *** the Michael-Simon Sobolev inequality,this inequality includes a term involving the mean *** extends a recent result of Brendle with Euclidean setting.

关键词： Logarithmic Sobolev inequality Nonnegative sectional curvature Submanifold

State of research and trends in development of wood adhesives

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Forestry Studies in China 2011年第4期13卷 321-326页

作者： ZHAO Lei-feng LIU yu XU zheng-dong ZHANG Ya-zhuo ZHAO Fang ZHANG Shuang-bao College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

We aim to present an overview of the status of adhesives in the wood industry, especially in the area of wood-based panels. The review summarizes the current state of research of two kinds of adhesives, i.e., synthetic adhesives and natural adhesives. Synthetic adhesives, consisting of urea-formaldehyde resins （UF）, phenol-formaldehyde resins （PF）, polyvinyl acetate emulsion （PVAc） and isocyanates, are widely used. For UF, most investigations are concerned with the reduction of free formaldehyde; for PF, most studies focus on finding new chemicals to replace phenol. PVAc has poor properties, but these can be improved by a blending reactions and copolymerization with other chemicals. Isocyanate is an environmentally friendly synthetic adhesive, but also suffers from inadequate properties. Natural adhesives, such as protein/starch, lignin and tannins, have poor bonding effect that limits their level of use, but their main advantages are that they are environmentally friendly and a renewable resource. Studies of modification can improve the bonding performances and gradually cause natural adhesives to become applied in industrial production. Some proposals for future development and the importance of environmentally friendly adhesives are provided, which will be helpful in future theoretical and experimental research.

关键词： synthetic adhesives natural adhesives main features development trend

Laryngopharyngeal reflux disease:Updated examination of mechanisms,pathophysiology,treatment,and association with gastroesophageal reflux disease

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World Journal of Gastroenterology 2024年第16期30卷 2209-2219页

作者： Na Cui Ting Dai Yang Liu Ya-yu Wang Jia-yu Lin Qing-Fan zheng dong-dong Zhu Xue-Wei Zhu Department of Otorhinolaryngology Head and Neck Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Ultrasound China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Gastroenterology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

Laryngopharyngeal reflux disease(LPRD)is an inflammatory condition in the laryngopharynx and upper aerodigestive tract mucosa caused by reflux of stomach contents beyond the *** commonly presents with symptoms such as hoarseness,cough,sore throat,a feeling of throat obstruction,excessive throat *** complex condition is thought to involve both reflux and reflex mechanisms,but a clear understanding of its molecular mechanisms is still ***,there is no standardized diagnosis or treatment *** strategies for LPRD mainly include lifestyle modifications,proton pump inhibitors and endoscopic *** paper seeks to provide a comprehensive overview of the existing literature regarding the mechanisms,pathophysiology and treatment of *** also provide an in-depth exploration of the association between LPRD and gastroesophageal reflux disease.

关键词： Laryngopharyngeal reflux Gastroesophageal reflux Head neck surgery Laryngitis Otolaryngology