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Environments favorable to healthy lifestyles:A systematic review of initiatives in Canada 被引量:1
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作者 Tegwen Gadais Maude Boulanger +1 位作者 Francois Trudeau Marie-Claude Rivard 《Journal of Sport and Health Science》 SCIE 2018年第1期7-18,共12页
Background: In recent years, a number of initiatives aimed at promoting healthy lifestyles in health-friendly environments have been implemented.The purpose of this review is to synthesize initiatives conducted in Can... Background: In recent years, a number of initiatives aimed at promoting healthy lifestyles in health-friendly environments have been implemented.The purpose of this review is to synthesize initiatives conducted in Canada and documented in publications for the period 1995–2015 in order to gain a better understanding of their objectives and impacts.Methods: A systematic review of Canadian initiatives published over the past 20 years was conducted from multiple databases(i.e., Scopus,SPORTDiscus, Pub Med, Academic search complete, Reseausante.com, Cairn, and Erudit). In total, 264 publications were identified and retained for the final analysis based on 5 criteria:(1) publication between 1995 and 2015,(2) online availability,(3) research conducted in Canada,(4) main topic related to environments favorable to healthy lifestyles(EFHL), and(5) publication in French or English.Results: A sharp increase in the number of studies on EFHL was observed between 2010 and 2015(57%). Two major lifestyle components—physical activity and nutrition—and 2 environmental aspects—neighborhood and built environment—were the elements most frequently examined regarding adults(48%), young people(34%), and seniors(9%), using quantitative(60%) and qualitative(18%) methods. Furthermore, the analysis reveals a greater focus on the municipal(53%) than the national or provincial levels(31%).Conclusion: This work is a first map of Canadian studies related to EFHL. It clarifies the definition of EFHL and classifies its components. As well,it documents the issues raised, the research methods employed, and the role of stakeholders, while outlining a new research agenda that includes dimensions of EFHL formerly neglected by researchers, namely, political and sociocultural spheres of action.? 2018 Production and hosting by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Built environment CANADA favorable environment Healthy lifestyle INITIATIVES NEIGHBORHOOD NUTRITION Physical activity
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Reservoir Characteristics and Favorable Area Prediction of Chang-6 Reservoir in Zhouguan Area, Ordos Basin
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作者 Yuchuan Liu Mingju Tang Shengli Gao 《Journal of Geoscience and Environment Protection》 2023年第8期22-32,共21页
Based on the analysis of a large number of core samples, logging results, logging interpretation data and dynamic data in the study area, the characteristics of Chang 6 reservoir in Zhouguan area of Baihe area are stu... Based on the analysis of a large number of core samples, logging results, logging interpretation data and dynamic data in the study area, the characteristics of Chang 6 reservoir in Zhouguan area of Baihe area are studied, and the favorable reservoir areas in the study area are predicted. The results show that the lithology of Chang 6 reservoir is mainly light gray and gray fine-grained to very fine-grained feldspar lithic sandstone. The pore types are mainly residual intergranular pores and feldspar dissolved pores, including debris dissolved pores and microfractures. The porosity and permeability values are low, which belongs to low porosity-low permeability and ultra-low permeability reservoirs. According to the reservoir distribution characteristics and related data, the Chang 6 reservoir in the study area is divided into two types, mainly Class II and Class III reservoirs. The comprehensive evaluation predicts that the spatial distribution of the favorable area of Chang 6 reservoir is not uniform, but the distribution area is large, which has broad exploration and development value, and provides the necessary conditions for the distribution study of the favorable oil-bearing zone in this area and the preparation for the next exploration and development. 展开更多
关键词 Extension Group Baihe Oil Region Sedimentary Microfacies Basic Characteristics of Reservoir favorable Zone
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Favorable lithofacies and pore characteristics of the Permian Longtan Formation shale in the southern Sichuan Basin
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作者 Ya'na Chen Kai Yang +3 位作者 Wei Wu Yuran Yang Xue Yang Kai Ma 《Energy Geoscience》 2023年第3期210-219,共10页
The marine–continental transitional shale (MCTS) reservoirs of the Longtan Formation (LTF) are widely distributed in the Sichuan Basin. However, the LTF shale exhibits considerable variations in mineral composition a... The marine–continental transitional shale (MCTS) reservoirs of the Longtan Formation (LTF) are widely distributed in the Sichuan Basin. However, the LTF shale exhibits considerable variations in mineral composition and pore characteristics, which makes identifying the 'sweet spot'a challenging task. To address this issue, 10 samples from four typical shale gas wells in the LTF in the southern Sichuan Basin were selected and analyzed for total organic carbon (TOC) content, whole-rock composition using X-ray diffraction (XRD), low-pressure gas adsorption, and high-pressure mercury intrusion. The lithofacies distribution and pore structure of the MCTS were studied to determine the pore structural characteristics and the primary factors influencing pore formation in different types of shale lithofacies in the LTF. The lithofacies of the LTF shale in the study area can be classified into three categories: siliceous clay shale, clay shale and mixed shale. Mineral content has a significant impact on the pore characteristics, while TOC content has a minor effect on the pore volume and specific surface area of micropores and mesopores. It can be inferred that the mesopores in the MCTS are mainly related to clay mineral pores, and mineral dissolution and TOC content are not the primary factors contributing to pore formation. 展开更多
关键词 Pore Characteristics Sweet spot Favor able lithofacies Marine-coninental transitional shale Longtan Fomaion si chuan Basin
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A hydrocarbon enrichment model and prediction of favorable accumulation areas in complicated superimposed basins in China 被引量:16
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作者 Pang Xiongqi Meng Qingyang +2 位作者 Jiang Zhenxue Liu Luofu Lu Xiuxiang 《Petroleum Science》 SCIE CAS CSCD 2010年第1期10-19,共10页
The geologic conditions of superimposed basins in China are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydro... The geologic conditions of superimposed basins in China are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydrocarbon generation and expulsion from source rocks, multi-cycle hydrocarbon enrichment and accumulation, and multi-phase reservoir adjustment and reconstruction. The enrichment, accumulation and distribution of hydrocarbon is mainly controlled by the source rock kitchen, paleo- anticline, regional cap rock and intensity of tectonic movement. In this paper, the T-BCMS model has been developed to predict favorable areas of hydrocarbon accumulation in complicated superimposed basins according to time and spatial relationships among five key factors. The five factors include unconformity surface representing tectonic balancing (B), regional cap rock representing hydrocarbon protection (C), paleo-anticline representing hydrocarbon migration and accumulation (M), source rock kitchen representing hydrocarbon generation and expulsion (S) and geological time (T). There are three necessary conditions to form favorable areas of hydrocarbon accumulation. First, four key factors BCMS should be strictly in the order of BCMS from top to bottom. Second, superimposition of four key factors BCMS in the same area is the most favorable for hydrocarbon accumulation. Third, vertically ordered combination and superimposition in the same area of BCMS should occur at the same geological time. The model has been used to predict the most favorable exploration areas in Ordovician in the Tarim Basin in the main hydrocarbon accumulation periods. The result shows that 95% of the discovered Ordovician hydrocarbon reservoirs are located in the predicted areas, which indicates the feasibility and reliability of the key factor matching T-BCMS model for hydrocarbon accumulation and enrichment. 展开更多
关键词 Complicated superimposed basin key factor matching T-BCMS model favorable area for hydrocarbon accumulation hydrocarbon distribution prediction
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Palaeogeomorphology and its control on the development of sequence stratigraphy and depositional systems of the Early Silurian in the Tarim Basin 被引量:14
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作者 Liu Jingyan Lin Changsong +8 位作者 Cai Zhenzhong Zhu Yongfeng Yang Yongheng Peng Li Si Baoling Huang Zhen Li Huanpu Xu Yingcai Su Zhenzhen 《Petroleum Science》 SCIE CAS CSCD 2010年第3期311-322,共12页
The Silurian in the Tarim Basin was deposited on the basement deformed by the Caledonian tectonic movements at the end of the Late Ordovician. The development and distribution of sedimentary sequences of the Early Sil... The Silurian in the Tarim Basin was deposited on the basement deformed by the Caledonian tectonic movements at the end of the Late Ordovician. The development and distribution of sedimentary sequences of the Early Silurian have been clearly controlled by the palaeogeomorphology of the Late Ordovician. Based on unconformity characteristics and distribution of erosion, several zones can be differentiated including a high uplifted erosion zone, a transitional slope zone and a depression zone. The central and west Tabei Uplift zones show high angular unconformity and intense erosion. The Tarim Basin in the late Ordovician shows characteristics of higher in the west, lower in the east while higher in the south, lower in the north. The Early Silurian mainly developed transgressive and highstand systems tracts on the whole, while the lowstand systems tract only developed partly below the slope break. The palaeogeomorphology controlled the elastic source supply and deposit distribution. Braided delta system and tidal flat-estuary system were deposited. The duration of uplifting of the Tazhong paleo- uplift was longer than that of the Tabei paleo-uplift, and deposition was later. This led to the lower and middle members of the Kepingtage Formation missing in that area. As a large-scale transgression occurred during the deposition period of the upper member of the Kepingtage Formation, sediment from the west of the basin was transported and deposited by tides and waves, forming tidal-marine debris systems above the uplift. Proximal alluvial fan and fan delta coarse elastic deposits developed in proximal uplift zone in the east and southeast of the basin, and braided delta put forward to the transitional zone between the edge of uplift and the sea. Large-scale tidal channel, sub-distributary channel and mouth bar of the delta front can form favorable reservoirs, and they are primary targets for oil and gas exploration. This research on sequence-depositional systems development and distribution controlled by palaeogeomorphology is significant in guiding the prediction of reservoir sandstones. 展开更多
关键词 Erosional palaeogeomorphology depositional palaeogeomorphology evolution of paleo- uplift sequence-depositional system favorable reservoir facies zone
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Multiple-Element Matching Reservoir Formation and Quantitative Prediction of Favorable Areas in Superimposed Basins 被引量:8
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作者 WANG Huaijie PANG Xiongqi +3 位作者 WANG Zhaoming YU Qiuhua HUO Zhipeng MENG Qingyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1035-1054,共20页
Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation, and complex hydrocarbon reservoirs have been discovered widely in basins of this kind. Mos... Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation, and complex hydrocarbon reservoirs have been discovered widely in basins of this kind. Most of the complex hydrocarbon reservoirs are characterized by relocation, scale re-construction, component variation and phase state transformation, and their distributions are very difficult to predict. Research shows that regional caprock (C), high-quality sedimentary facies (Deposits, D), paleohighs (Mountain, M) and source rock (S) are four geologic elements contributing to complex hydrocarbon reservoir formation and distribution of western superimposed basins. Longitudinal sequential combinations of the four elements control the strata of hydrocarbon reservoir formation, and planar superimpositions and combinations control the range of hydrocarbon reservoir and their simultaneous joint effects in geohistory determine the time of hydrocarbon reservoir formation. Multiple-element matching reservoir formation presents a basic mode of reservoir formation in superimposed basins, and we recommend it is expressed as T-CDMS. Based on the multiple-element matching reservoir formation mode, a comprehensive reservoir formation index (Tcdms) is developed in this paper to characterize reservoir formation conditions, and a method is presented to predict reservoir formation range and probability of occurrence in superimposed basins. Through application of new theory, methods and technology, the favorable reservoir formation range and probability of occurrence in the Ordovician target zone in Tarim Basin in four different reservoir formation periods are predicted. Results show that central Tarim, Yinmaili and Lunnan are the three most favorable regions where Ordovician oil and gas fields may have formed. The coincidence of prediction results with currently discovered hydrocarbon reservoirs reaches 97 %. This reflects the effectiveness and reliability of the new theory, methods and technology. 展开更多
关键词 superimposed basin complex hydrocarbon reservoir elements matching reservoirformation prediction of favorable hydrocarbon accumulation zone Tarim Basin
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Control of paleogeographic pattern on sedimentary differentiation of evaporite-carbonate symbiotic system:A case study of the sixth sub-member of Ordovician Majiagou Formation M5 Member in central-eastern Ordos Basin,NW China 被引量:2
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作者 ZHONG Shoukang TAN Xiucheng +8 位作者 HU Guang NIE Wancai YANG Mengying ZHANG Daofeng ZHENG Jianfeng XU Jie DONG Guodong XIAO Di LU Zixing 《Petroleum Exploration and Development》 CSCD 2022年第4期837-850,共14页
The relationship between paleogeographic pattern and sedimentary differentiation of evaporite-carbonate symbiotic system is examined based on logging,core and thin section data,by taking the sixth sub-member of fifth ... The relationship between paleogeographic pattern and sedimentary differentiation of evaporite-carbonate symbiotic system is examined based on logging,core and thin section data,by taking the sixth sub-member of fifth member of Ordovician Majiagou Formation(M56)in the central-eastern Ordos Basin as an example.(1)Seven sub-geomorphic units(Taolimiao west low,Taolimiao underwater high,Taolimiao east low,Hengshan high,East salt low,North slope and Southwest slope)developed in the study area.(2)The“three lows”from west to east developed dolomitic restricted lagoon,evaporite evaporative lagoon and salt evaporative lagoon sedimentary facies respectively,the"two highs"developed high-energy grain beach and microbial mound,and the north and south slopes developed dolomitic flats around land.(3)The paleogeographic pattern caused natural differentiation of replenishment seawater from the northwest Qilian sea,leading to the eccentric sedimentary differentiation of dolomite,evaporite and salt rock symbiotic system from west to east,which is different from the classic“bull's eye”and“tear drop”distribution patterns.(4)As the Middle Qilian block subducted and collided into the North China Plate,the far-end compression stress transferred,giving rise to the alternate highland and lowland in near north to south direction during the sedimentary period of M56 sub-member.(5)Taolimiao underwater high and Hengshan high developed favorable zones of microbial mounds and grain shoals in south to north strike in M56 sub-member,making them favorable exploration areas with great exploration potential in the future. 展开更多
关键词 paleogeographic pattern sedimentary differentiation evaporite and carbonate rock favorable reservoir facies zone Ordovician Majiagou Formation Ordos Basin
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Favorable lithofacies types and genesis of marine- continental transitional black shale: A case study of Permian Shanxi Formation in the eastern margin of Ordos Basin, NW China 被引量:1
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作者 WU Jin WANG Hongyan +7 位作者 SHI Zhensheng WANG Qi ZHAO Qun DONG Dazhong LI Shuxin LIU Dexun SUN Shasha QIU Zhen 《Petroleum Exploration and Development》 CSCD 2021年第6期1315-1328,共14页
Based on core description,thin section identification,X-ray diffraction analysis,scanning electron microscopy,low-temperature gas adsorption and high-pressure mercury intrusion porosimetry,the shale lithofacies of Sha... Based on core description,thin section identification,X-ray diffraction analysis,scanning electron microscopy,low-temperature gas adsorption and high-pressure mercury intrusion porosimetry,the shale lithofacies of Shan23 sub-member of Permian Shanxi Formation in the east margin of Ordos Basin was systematically analyzed in this study.The Shan23 sub-member has six lithofacies,namely,low TOC clay shale(C-L),low TOC siliceous shale(S-L),medium TOC siliceous shale(S-M),medium TOC hybrid shale(M-M),high TOC siliceous shale(S-H),and high TOC clay shale(C-H).Among them,S-H is the best lithofacies,S-M and M-M are the second best.The C-L and C-H lithofacies,mainly found in the upper part of Shan23 sub-member,generally developed in tide-dominated delta facies;the S-L,S-M,S-H and M-M shales occurring in the lower part of Shan23 sub-member developed in tide-dominated estuarine bay facies.The S-H,S-M and M-M shales have good pore struc-ture and largely organic matter pores and mineral interparticle pores,including interlayer pore in clay minerals,pyrite inter-crystalline pore,and mineral dissolution pore.C-L and S-L shales have mainly mineral interparticle pores and clay mineral in-terlayer pores,and a small amount of organic matter pores,showing poorer pore structure.The C-H shale has organic mi-cro-pores and a small number of interlayer fissures of clay minerals,showing good micro-pore structure,and poor meso-pore and macro-pore structure.The formation of favorable lithofacies is jointly controlled by depositional environment and diagen-esis.Shallow bay-lagoon depositional environment is conducive to the formation of type II2 kerogen which can produce a large number of organic cellular pores.Besides,the rich biogenic silica is conducive to the preservation of primary pores and en-hances the fracability of the shale reservoir. 展开更多
关键词 marine-continental transitional facies shale gas favorable lithofacies reservoir characteristics Permian Shanxi Formation Ordos Basin
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A REVERSED-FRAME NORMALIZATION DESIGN OF ROBUST FLIGHT CONTROL SYSTEM
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作者 Jiang Changsheng, Shen Chunlin and Hu ZhonghanNanjing Aeronautical Institute 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1991年第1期35-45,共11页
In this paper, a discussion is devoted to the theory and method of a reversed-frame normalization design to robust flight control system. The robust stability theory of the normal transfer function matrix with the sam... In this paper, a discussion is devoted to the theory and method of a reversed-frame normalization design to robust flight control system. The robust stability theory of the normal transfer function matrix with the same characteristic gain loci is proved. An example of flight control system design shows the application and advantage of this method. 展开更多
关键词 devoted robustness discussion NORMALIZATION REQUIREMENT NOMINAL favorable DISTURBANCE GAINS Feedback
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Structural characteristics of the basement and the prospective of favorable oil and gas blocks in the Tacheng basin
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作者 Guoqing Zhang Junmeng Zhao +2 位作者 Hua Bai Ming Wan Xiaoyang Guo 《Earthquake Science》 CSCD 2012年第5期527-534,共8页
The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic... The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic and gravimetric data, skeleton seismic profiles, magnetotelluric profiles and drilling data. Here, we present gravimetric and magnetic data analyses of the basement structures of the Tacheng basin and its base formation. We also provide a magnetotelluric profile analysis of the structural features and tectonic framework of basin-mountain patterns. We use local geology, drilling data, and other comprehensive information to document the tectonic framework of the basement of the basin. Small-scale nappe structures are found in the northern basin, whereas stronger and more pronounced thrusting structures are found to the south and east of the basin. The basin is divided into four first-order tectonic units: a central uplift, a northern depression, a southeastern depression and a western depression. In addition, the Emin sag is suggested as a possible reservoir for oil and gas. 展开更多
关键词 northern Xinjiang Tacheng basin basement structure basin and mountain relation-ship tectonic unit division favorable area
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Comparison of natural grassy ELM behavior in favorable/unfavorable Bt in EAST
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作者 丁根凡 杨清泉 +11 位作者 徐国盛 林新 叶扬 陈冉 王嵎民 臧庆 兰恒 陈良 卢智康 王一丰 孟令义 王亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第9期49-59,共11页
The properties of grassy edge-localized modes(ELMs)in EAST in the favorable and unfavorable Btare statistically studied.Statistical analysis indicates that there is no systematical difference in the frequencies of gra... The properties of grassy edge-localized modes(ELMs)in EAST in the favorable and unfavorable Btare statistically studied.Statistical analysis indicates that there is no systematical difference in the frequencies of grassy ELMs under the two different magnetic configurations in the similar parameter spaces.The high-frequency grassy ELM(fELM>1 k Hz)in unfavorable Bt is dependent on the high poloidal betaβpand high triangularityδu,while the high-frequency grassy ELM(fELM>1k Hz)in favorable Btappears to rely on the high plasma density.A frequently occurring phenomenon in favorable Btdefined as‘clustered ELM’seems to be the most evident difference in ELM behavior between favorable and unfavorable Bt.Statistical analysis shows that larger plasma-wall outer gap,longer plasma elongation,lower low-hybrid wave heating power and electron cyclotron resonance heating power favor the occurrence of clustered grassy ELMs.Further studies indicate that the generation of clustered grassy ELMs could be correlated with the lower electron temperature in the bulk plasma. 展开更多
关键词 grassy ELM favorable and unfavorable Bt clustered ELM EAST
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New delineation of two favorable zones for gas hydrate in southem Qinghai and northern Tibet,China
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作者 Shuai Zhang Ping-kang Wang +2 位作者 You-hai Zhu Rui Xiao Shou-ji Pang 《China Geology》 2018年第2期304-305,共2页
1.ObjectivesSouthern Qinghai-northem Tibet permafrost region is a place having the most widespread and most developed permafrost in China with good mineralization conditions and prospecting potentials for gas hydrate ... 1.ObjectivesSouthern Qinghai-northem Tibet permafrost region is a place having the most widespread and most developed permafrost in China with good mineralization conditions and prospecting potentials for gas hydrate (Zhu YH et al.,2011). In 2011,China Geological Survey initiated a special national program entitled "Gas hydrate resource exploration and trial mining",which signaled a prelude to a comprehensive gas hydrate survey in southern Qinghai-northern Tibet permafrost region.So far,appreciable progress has been made in the geological,geophysical,geochemical and drilling survey across a number of key blocks.This paper is intended to examine the fundamental conditions for gas hydrate mineralization based on previous findings,delineate favorable zones for gas hydrate mineralization,and to make contributions to the onshore gas hydrate resource exploration in China. 展开更多
关键词 NEW DELINEATION TWO favorable zones gas HYDRATE
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Creating A Favorable Environment
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作者 Cui Liru Cui Liru is Director and Professor at the International Information Research Institute. 《Contemporary International Relations》 2003年第1期19-22,共4页
I will discuss the current international environment China is facing from the following three aspects: First, it is necessary to calmly and obiectively evaluate other countries’ attitude toward China because this inv... I will discuss the current international environment China is facing from the following three aspects: First, it is necessary to calmly and obiectively evaluate other countries’ attitude toward China because this involves their China 展开更多
关键词 ASIA into FORM Creating A favorable Environment of that
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Favorable and unfavorable amino acid residues in water-soluble and transmembrane proteins
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作者 Hiroshi Nakashima Ayano Yoshihara Kei-ichiro Kitamura 《Journal of Biomedical Science and Engineering》 2013年第1期36-44,共9页
We analyzed the amino acid residues present in the water-soluble and transmembrane proteins of 6 thermophilic and 6 mesophilic species of the domains Archaea and Eubacteria, and characterized them as favorable or unfa... We analyzed the amino acid residues present in the water-soluble and transmembrane proteins of 6 thermophilic and 6 mesophilic species of the domains Archaea and Eubacteria, and characterized them as favorable or unfavorable. The characterization was performed by comparing the observed number of each amino acid residue to the expected number calculated from the percentage of nucleotides present in each gene. Amino acids that were more or less abundant than expected were considered as favorable or unfavorable, respectively. Comparisons of amino acid compositions indicated that the water-soluble proteins were rich in charged residues such as Glu, Asp, Lys, and His, whereas hydrophobic residues such as Trp, Phe, and Leu were abundant in transmembrane proteins. Interestingly, our results found that although the Trp residue was abundant in transmembrane proteins, it was not defined as favorable by our calculations, indicating that increased numbers of a particular amino acid does not necessary indicate it is a favorable residue. Amino acids with high G + C content such as Ala, Gly, and Pro were frequently observed as favorable in species with low G + C content. Comparatively, amino acids with low G + C content such as Phe, Tyr, Lys, Ile, and Met were frequently observed as favorable in species with high G + C content. These are the examples to increase the supply of amino acids than expected. Amino acids with neutral G + C content, i.e., Glu and Asp were favorable in water-soluble proteins from all species analyzed, and Cys was unfavorable both in water-soluble and transmembrane proteins. These results indicate that amino acid compositions are essentially determined by the nucleotide sequence of the genes, and the amino acid content is altered by a deviation from expectation. 展开更多
关键词 Amino Acid COMPOSITION NUCLEOTIDE COMPOSITION favorable and Unfavorable Residues WATER-SOLUBLE and TRANSMEMBRANE Proteins THERMOPHILIC and MESOPHILIC Species
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Aerodynamic Optimization of the Expansion Section in a Hypersonic Quiet Nozzle Based on Favorable Pressure Effect
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作者 Jian Gong Dapeng Yao Xunhua Liu 《Journal of Applied Mathematics and Physics》 2014年第6期443-448,共6页
Maximum expansion angle is the primary parameter for the design of expansion section of hypersonic quiet nozzle. According to the quantity of maximum expansion angle, expansion section could be classified as fast expa... Maximum expansion angle is the primary parameter for the design of expansion section of hypersonic quiet nozzle. According to the quantity of maximum expansion angle, expansion section could be classified as fast expansion and slow expansion. In order to diminish the effect of instability of G&ouml;rtler vortex, gradually, slow expansion was employed for quiet nozzle design. Based on the favorable pressure effect, the maximum expansion angle is optimized in this paper, and a considerable selective session of maximum expansion angle is obtained. The trend that slow expansion is employed instead of fast expansion is explained, and a new method is established for aerodynamic optimization of expansion section contour in a quiet nozzle. 展开更多
关键词 QUIET NOZZLE MAXIMUM EXPANSION ANGLE favorable Pressure Effect
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Development unit division and favorable area evaluation for joint mining coalbed methane
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作者 YANG Zhaobiao LI Yangyang +6 位作者 QIN Yong SUN Hansen ZHANG Ping ZHANG Zhengguang WU Congcong LI Cunlei CHEN Changxiao 《Petroleum Exploration and Development》 2019年第3期583-593,共11页
Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step metho... Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step method” of optimal combination of production layers is corrected, and then the CBM production layer potential index is introduced to evaluate favorable areas for commingled multi-coal seam production. Through analysis of the key parameters of coal reservoirs affecting the CBM productivity index, a development unit division method for areas with multi-coal seams is established, and a quantitative grading index system is proposed. On this basis, the evaluation process of CBM development favorable area is developed: the mature 3-D modeling technology is used to characterize the reservoir physical properties of multi-coal seams in full-scale;the production layer potential index of each grid is calculated, and the production layer potential index contour under single-layer or commingled multi-layer production are plotted;according to the distribution of the contour of production layer potential index, the quantitative index of CBM development unit is adopted to outline the grade I, II, III coal reservoir distribution areas, and thus to pick out the favorable development areas. The practical application in the Yuwang block of Laochang in Yunnan proved that the favorable area evaluation process proposed can effectively overcome the defects of selecting favorable development areas only relying on evaluation results of a major coal seam pay, and enhance the accuracy of the evaluation results, meeting the requirements of selecting favorable areas for multi-coal seam commingled CBM production. 展开更多
关键词 coalbed methane reservoir physical property JOINT MINING production layer potential INDEX DEVELOPMENT unit DIVISION quantitative INDEX favorable area EVALUATION
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Characterization of favorable lithofacies in tight sandstone reservoirs and its significance for gas exploration and exploitation: A case study of the 2nd Member of Triassic Xujiahe Formation in the Xinchang area, Sichuan Basin
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作者 LIU Junlong LIU Zhongqun +2 位作者 XIAO Kaihua HUANG Yanqing JIN Wujun 《Petroleum Exploration and Development》 2020年第6期1194-1205,共12页
By using core,logging curves,and experiment data,favorable lithofacies types in the 2 nd Member of Triassic Xujiahe Formation in the Xinchang area,Sichuan Basin were classified,standard of the favorable lithofacies wa... By using core,logging curves,and experiment data,favorable lithofacies types in the 2 nd Member of Triassic Xujiahe Formation in the Xinchang area,Sichuan Basin were classified,standard of the favorable lithofacies was established,planar distribution regularities of the favorable lithofacies were identified,and forming mechanisms of the favorable lithofacies and their control effect on production were examined.(1)The 2 nd Member of Xujiahe Formation has twelve types of lithofacies,among which multiple layer medium-coarse grain sandstone lithofacies,parallel bedding medium-coarse grain sandstone lithofacies,massive bedding medium-coarse grain sandstone lithofacies,inclined bedding medium-coarse grain sandstone lithofacies,and charcoal-bearing medium-coarse grain sandstone lithofacies with better physical properties and higher gas content are favorable lithofacies;they feature low gamma,low neutron porosity,low resistivity,and high acoustic travel time on logging curves.(2)The sedimentary process controls spatial distribution of sand bodies which are the material basis of the favorable lithofacies;post diagenetic fluids would differentially reconstruct the favorable lithofacies;tectonic activities and abnormal formation pressure made strata slide along the weakness plane,giving rise to fractures in different types of rocks,which can enhance the reservoir permeability significantly.(3)The development degree of favorable lithofacies is a major factor affecting stable production of gas well. 展开更多
关键词 tight sandstone reservoir favorable lithofacies reservoir characterization Triassic Xujiahe Formation Xinchang area Sichuan Basin
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The electric scheme option for Three Gorges Hydropower Station and the System
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作者 Ji Wen Electric Power Planning and Design General Institute Xu Jintao 《Electricity》 1992年第2期29-34,共6页
EDlTOR’S NOTE: We had published an article on Vol.1, No.1 of this Journal entitled "A study on the schemes of power trons-mission from Three Gorges Project to East China", in which various possible options ... EDlTOR’S NOTE: We had published an article on Vol.1, No.1 of this Journal entitled "A study on the schemes of power trons-mission from Three Gorges Project to East China", in which various possible options were discussed from the researcher’s point of view.This paper we present here discusses the same problem but from the planner/designer’s point of view. These different viewpoints aresurely helpful to the final decision of the huge project. We expect some further discussions on this problem to be published on ourJournal. 展开更多
关键词 entitled DESIGNER helpful EXPECT discussions OPTION YANGTZE favorable operated AUTHORITY
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Analysis of the changes in forest ecosystem functions,structure and composition in the Black Sea region of Turkey
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作者 Sedat Keles Idris Durusoy Günay Cakir 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期329-342,共14页
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units... We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types,tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas(especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches. 展开更多
关键词 ecosystem forests timber stand biomass stock favorable closure rehabilitation Turkey
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Newly Amended Payment of Royalties Favorable for Sino-foreign Cooperative Exploitation of Petroleum Resources on Land
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《China Oil & Gas》 CAS 1995年第4期52-52,共1页
NewlyAmendedPaymentofRoyaltiesFavorableforSino-foreignCooperativeExploitationofPetroleumResourcesonLandAsChi... NewlyAmendedPaymentofRoyaltiesFavorableforSino-foreignCooperativeExploitationofPetroleumResourcesonLandAsChina'sthirdroundofi... 展开更多
关键词 FOREIGN COOPERATIVE SINO favorable PAYMENT Royalties EXPLOITATION
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