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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong Hui Li Ya‑Qin Zhang Department of Growth and development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Fine description of unconventional clastic oil reservoirs

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Petroleum Research 2024年第2期9卷 289-303页

作者： Huanqing Chen Research institute of Petroleum Exploration&development PetroChinaChina

The latest researches reveal that studies on unconventional clastic oil reservoirs in China generally lag far behind those in other countries in respect of content and *** study presents the definition and classification of unconventional oil reservoirs and analyzes the problems in the fine description of unconventional oil *** key content of the fine description of unconventional oil reservoirs is summarized from four aspects:fine fracture characterization based on fine structure interpretation,reservoir architecture characterization based on sedimentary facies,characteristics of nanoscale microscopic pore structure of reservoir,and evaluation of source rock and“sweet spot zone”.Finally,this study suggests that development of fine description of unconventional clastic oil reservoirs in the future should focus on rock brittleness analysis and fracture modeling,geophysical characterization of unconventional clastic oil reservoirs,fluid description of tight reservoirs,and physical/numerical simulation experiments of unconventional oil reservoirs.

关键词： Unconventional clastic reservoir Fine reservoir description Oil sand Tight oilShale oil Fracture characterization Nanoscale microscopic pore structure Sweet spot

Application of sparse S transform network with knowledge distillation in seismic attenuation delineation

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Petroleum Science 2024年第4期21卷 2345-2355页

作者： Nai-Hao Liu Yu-Xin Zhang Yang Yang Rong-Chang Liu Jing-Huai Gao Nan Zhang School of Information and Communications Engineering Xi'an Jiaotong University School of Software Engineering Xi'an Jiaotong University PetroChina Research institute of Petroleum Exploration and development (RIPED) CNPC Research institute of Exploration and development Yumen Oilfield Company CNPC

Time-frequency analysis is a successfully used tool for analyzing the local features of seismic ***, it suffers from several inevitable limitations, such as the restricted time-frequency resolution,the difficulty in selecting parameters, and the low computational efficiency. Inspired by deep learning,we suggest a deep learning-based workflow for seismic time-frequency analysis. The sparse S transform network(SSTNet) is first built to map the relationship between synthetic traces and sparse S transform spectra, which can be easily pre-trained by using synthetic traces and training labels. Next, we introduce knowledge distillation(KD) based transfer learning to re-train SSTNet by using a field data set without training labels, which is named the sparse S transform network with knowledge distillation(KD-SSTNet).In this way, we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training labels. To test the availability of the suggested KD-SSTNet, we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods.

关键词： S transform Deep learning Knowledge distillation Transfer learning Seismic attenuation delineation

Promoting grain production through high-standard farmland construction:Evidence in China

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Journal of Integrative Agriculture 2024年第1期23卷 324-335页

作者： Shuai Hao Guogang Wang Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang institute of Agricultural Economics and development Chinese Academy of Agricultural SciencesBeijing 100081China

Food security is a strategic priority for a country’s economic *** China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production *** on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)*** results showed that HSFC significantly increased total grain production,which is robust to various *** increased grain yield through three potential ***,it could increase the grain replanting ***,it could effectively reduce yield loss due to droughts and ***,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding *** analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced *** addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean *** findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production *** the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields.

关键词： high-standard farmland farmland construction food security food production area difference-in-differences

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Characteristics and genesis of tuffaceous shale oil lithofacies:A case study of Lucaogou Formation in Santanghu Basin

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Petroleum Research 2024年第1期9卷 37-47页

作者： Dongsheng Xiao Xiong fei Xu Jilun Kang Yiting Zhang PetroChina Tuha Oilfield Company Exploration and development Research institute China

Lucaogou Formation in the Santanghu Basin is a special lacustrine fine-grained sedimentary deposits rich in volcanic debris and carbonate,with abundant shale oil ***,understanding of shale oil characteristics and genesis remains ***,sedimentary environment,and formation mechanisms of tuffaceous shale oil are investigated based on core and thin section observations,X-ray diffraction,field emission SEM and geochemical *** show that three mixed lithofacies types are developed in Lucaogou Formation:blocky tuff,laminated tuffaceous dolomite,and laminated dolomitic *** lithofacies types are characterized by high content of felsic and dolostone,widespread organic matter,and low clay *** of tuffaceous shale oil sweet spots is primarily influenced by four factors:inputting of volcanic ash as a high-quality source rocks and reservoirs provides good material basis;devitrification of volcanic glass,calcitization,and dissolution are crucial for formation of reservoirs;expulsion of source rocks with high-abundance organic matter expulsion facilitates migration and accumulation of hydrocarbon in adjacent reservoirs;fracture development improves reservoir permeability to form highly productive sweet *** analyzing characteristics and genesis of tuffaceous shale oil,the main controlling factors of reservoir physical property and oil saturation are clarified,which is of great significance for selection of shale oil exploration zones.

关键词： shale oil Tuffaceous Formation mechanism Lucaogou formation Santanghu basin

Growth and development of children in China:achievements,problems and prospects

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World Journal of Pediatrics 2024年第2期20卷 97-104页

作者： Xin-Nan Zong Hui Li Department of Growth and development Capital Institute of PediatricsBeijing 100020China

Growth reflects the general condition of society,and is a measure of the nutritional and hygienic status of a population[1,2].Nutrition is one of the most important components of children’s well-being[3].The Chinese government attaches great importance to children’s health and development,with a clear statement and consistent practice for“Children are the future and hope of the motherland”.

关键词： mother statement children

Study of inter-well interference in shale gas reservoirs by a robust production data analysis method based on deconvolution

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Petroleum Science 2024年第4期21卷 2502-2519页

作者： Wen-Chao Liu Cheng-Cheng Qiao Ping Wang Wen-Song Huang Xiang-Wen Kong Yu-Ping Sun He-Dong Sun Yue-Peng Jia School of Civil and Resource Engineering University of Science and Technology Beijing PetroChina Research institute of Petroleum Exploration and development

In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering, this study proposes a robust production data analysis method based on deconvolution, which is used for multi-well inter-well interference research. In this study, a multi-well conceptual trilinear seepage model for multi-stage fractured horizontal wells was established, and its Laplace solutions under two different outer boundary conditions were obtained. Then, an improved pressure deconvolution algorithm was used to normalize the scattered production data. Furthermore, the typical curve fitting was carried out using the production data and the seepage model solution. Finally,some reservoir parameters and fracturing parameters were interpreted, and the intensity of inter-well interference was compared. The effectiveness of the method was verified by analyzing the production dynamic data of six shale gas wells in Duvernay area. The results showed that the fitting effect of typical curves was greatly improved due to the mutual restriction between deconvolution calculation parameter debugging and seepage model parameter debugging. Besides, by using the morphological characteristics of the log-log typical curves and the time corresponding to the intersection point of the log-log typical curves of two models under different outer boundary conditions, the strength of the interference between wells on the same well platform was well judged. This work can provide a reference for the optimization of well spacing and hydraulic fracturing measures for shale gas wells.

关键词： Shale gas Inter-well interference Deconvolution Production data analysis Typical curves Multi-stage fractured horizontal well

Callovian-Oxfordian sedimentary microfacies in the middle of Block B on the right bank of the Amu Darya Basin,Turkmenistan

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Energy Geoscience 2024年第2期5卷 249-262页

作者： Chongyang Wu Chuanjie Cheng Liangjie Zhang Bingsong Yu Hongjun Wang Petroleum Exploration and development Research institute SinopecBeijing100083China China University of Geosciences(Beijing) Beijing100083China Research institute of Petroleum Exploration and development PetroChinaBeijing100083China

The right bank of the Amu Darya Basin enjoys abundant natural gas resources,on which the Callovian-Oxfordian strata in the middle of Block B serve as the major horizons for natural gas ***,the characteristics and distribution patterns of the sedimentary microfacies in these strata are yet to be further *** on the analysis of data on drilling,logging,cores,and thin sections from 29 typical wells,as well as the regional sedimentary background,this study inferred that the middle of Block B evolved from the Callovian ramp platform into the Oxfordian rimmed ***,this study determined that the inner-ramp intertidal-subtidal shallow-water subfacies mainly developed during the Callovian and transitioned into the shallow shelf subfacies during the *** study identified eight sedimentary microfacies,namely reef knoll,reef-shoal complex,bioclastic shoal,psammitic shoal,bioherm,lime mud mound,intershoal(intermound),and static-water *** on research into the high-precision sequence-sedimentary microfacies framework,this study built a geological model for the development of sedimentary microfacies in the study *** to this geological model,the sedimentary microfacies in the study area are characterized by vertical alternation of reef-shoal complex,bioclastic(psammitic)shoal,bioherm,and intershoal ***,they show the development of reef knoll,reef-shoal complex,bioclastic(psammitic)shoal,and bioherm(or lime mud mound)laterally from west to east,with the physical properties of the reservoirs deteriorating from west to east *** microfacies of reef-shoal complex and the bioclastic(psammitic)shoal predominate in the study area,and their deposition and development are controlled by sequence boundaries and are also affected by *** Oxfordian reef-shoal complexes were largely inherited from the Callovian uplifts and show lateral seaward progradation.

关键词： Carbonate rock Sedimentary microfacies Evolutionary pattern Jurassic Amu Darya Basin Turkmenistan

Fracture network types revealed by well test curves for shale reservoirs in the Sichuan Basin,China

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Energy Geoscience 2024年第1期5卷 264-274页

作者： Yanyan Wang Hua Liu Xiaohu Hu Cheng Dai Sidong Fang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective development Petroleum Exploration and Development Research InstituteSinopecBeijing100083China

Pressure buildup testing can be used to analyze fracture network characteristics and conduct quantitative interpretation of relevant parameters for shale gas wells,thus providing bases for assessing the well productivity and formulating proper development *** study establishes a new well test interpretation model for fractured horizontal wells based on seepage mechanisms of shale reservoirs and proposes a method for identifying fracturing patterns based on the characteristic slopes of pressure buildup curves and curve combination *** pressure buildup curve patterns are identified to represent three types of shale reservoirs in the Sichuan Basin,namely the moderately deep shale reservoirs with high pressure,deep shale reservoirs with ultra-high pressure,and moderately deep shale reservoirs with normal *** on this,the relationship between the typical pressure buildup curve patterns and the fracture network types are put *** effects of three types of shale gas reservoir are compared and *** results show that typical flow patterns of shale reservoirs include bilinear flow in primary and secondary fractures,linear flow in secondary fractures,bilinear flow in secondary fractures and matrix,and linear flow in *** fracture network characteristics can be determined using the characteristic slopes of pressure buildup curves and curve *** linear flow in early secondary fractures is increasingly distinct with an increase in primary fracture ***,the bilinear flow in secondary fractures and matrix and the subsequent linear flow in the matrix occur as the propping and density of secondary fractures *** increase in the burial depth,in-situ stress,and stress difference corresponds to a decrease in the propping of primary fractures that expand along different directions in the shale gas wells in the Sichuan *** pressure buildup curve patterns exist in the Sichuan Basin and it

关键词： Shale gas Fractured horizontal well Well testing interpretation Flow pattern characterization Parameter inversion Fracture network characteristics Sichuan basin

Multi-spheric interactions driven differential formation and accumulation of hydrocarbon resources in the North Sea Basin

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Science China Earth Sciences 2024年第11期67卷 3397-3420页

作者： Rixiang ZHU Shuichang ZHANG Huajian WANG Xiaomei WANG Yuke LIU Wang ZHANG Fang HAO Zhijun JIN Key Laboratory of Deep Petroleum Intelligent Exploration and development Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Enhanced Oil & Gas Recovery Research Institute of Petroleum Exploration and Development China National Petroleum Corporation State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) institute of Energy Peking University

The North Sea Basin is the most important oil and gas producing area in Europe and the birthplace of many classic petroleum geological theories. From the perspective of multi-spheric interactions in the Earth, this study investigated the riftforeland-rift evolution process of the North Sea Basin, which was controlled by the deep dynamic driving forces of the continental collision orogeny, mantle plume uplift, and intraplate deformation. The North Sea Basin was found to have drifted northward since the Carboniferous and passed through the low-latitude Hadley and the mid-latitude Ferrel cells. Two sets of main hydrocarbon source rocks have formed, the coals and coal measures of the Upper Carboniferous Westphalian and the marine shale of the Upper Jurassic Kimmeridge Clay Formation. We propose that the deep processes, tectonic activity, and transgression-climate evolution jointly controlled the types and horizons of the source rocks, reservoirs, and seals in different regions of the North Sea Basin. In the southern North Sea Basin, a Carboniferous-Lower Triassic gas-rich petroleum system was formed,which is characterized by transitional coal measure source rocks, desert aeolian sandstone reservoirs, and evaporite cap rocks. In the northern North Sea Basin, an Upper Triassic-Paleogene oil-rich petroleum system was formed, which is characterized by marine graben-type source rocks, deltaic sandstone and marine limestone reservoirs, and marine tight marl and shale cap *** late tectonic burial and uplift in the North Sea Basin further controlled the processes of oil and gas generation and accumulation, ultimately leading to a differential distribution pattern which is oil rich in the northern part and gas rich in the southern part of the basin. In the future, there is an urgent need to re-examine the mechanisms for the petroleum generation and accumulation in large mature exploration areas(e.g., super basins such as the North Sea) and low exploration areas(e.g., the O

关键词： North Sea Basin Multi-spheric interactions Petroleum system Okhotsk Sea region