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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 resources.However,understanding of shale oil characteristics and genesis remains unclear.Lithofacies,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 analysis.Results show that three mixed lithofacies types are developed in Lucaogou Formation:blocky tuff,laminated tuffaceous dolomite,and laminated dolomitic tuff.These lithofacies types are characterized by high content of felsic and dolostone,widespread organic matter,and low clay content.Formation 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 spots.By 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

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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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 processes.We 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 cities.Methods A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in China.Height and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were assessed.Results 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 2005‒2015.An 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 percentile.The total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,respectively.The 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 areas.Conclusions 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 2005‒2015.More 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

Optimization of Gas-Flooding Fracturing development in Ultra-Low Permeability Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 595-607页

作者： Lifeng Liu Menghe Shi Jianhui Wang Wendong Wang Yuliang Su Xinyu Zhuang Tight Oil research institute PetroChina Research Institute of Petroleum Exploration&DevelopmentBeijing100083China Key Laboratory of Unconventional Oil&Gas development China University of Petroleum(East China)Qingdao266580China Oil&Gas Technology research institute Changqing Oilfield CompanyXi’an710018China

Ultra-low permeability reservoirs are characterized by small pore throats and poor physical properties, which areat the root of well-known problems related to injection and production. In this study, a gas injection floodingapproach is analyzed in the framework of numerical simulations. In particular, the sequence and timing of fracturechanneling and the related impact on production are considered for horizontal wells with different fracturemorphologies. Useful data and information are provided about the regulation of gas channeling and possible strategiesto delay gas channeling and optimize the gas injection volume and fracture parameters. It is shown that inorder to mitigate gas channeling and ensure high production, fracture length on the sides can be controlled andlonger fractures can be created in the middle by which full gas flooding is obtained at the fracture location in themiddle of the horizontal well. A Differential Evolution (DE) algorithm is provided by which the gas injectionvolume and the fracture parameters of gas injection flooding can be optimized. It is shown that an improvedoil recovery factor as high as 6% can be obtained.

关键词： Ultra-low permeability reservoir gas injection flooding component simulation fracture parameters intelligent optimization differential evolution

Coxsackievirus B3 HFMD animal models in Syrian hamster and rhesus monkey

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Virologica Sinica 2024年第2期39卷 290-300页

作者： Suqin Duan Wei Zhang Yongjie Li Yanyan Li Yuan Zhao Weihua Jin Quan Liu Mingxue Li Wenting Sun Lixiong Chen Hongjie Xu Jie Tang Jinghan Hou Zijun Deng Fengmei Yang Shaohui Ma Zhanlong He institute of Medical Biology Chinese Academy of Medical Sciences Medical Primate Research Center Peking Union Medical CollegeYunnan Key Laboratory of Vaccine Research Development on Severe Infectious DiseaseKunming650118China

Coxsackievirus B3(CVB3)is the pathogen causing hand,foot and mouth disease(HFMD),which manifests across a spectrum of clinical severity from mild to severe.However,CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis,failing to replicate human HFMD symptoms.Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys,there is no comprehensive data on CVB3.In this study,we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes.The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip,leading to nasopharyngeal colonization,acute severe pathological injury,and typical HFMD symptoms.Notably,the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage.In the subsequent study,rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms,viral excretion,serum antibody conversion,viral nucleic acids and antigens,and the specific organ damages,particularly in the heart.Surprisingly,there were no significant differences in myocardial enzyme levels,and the clinical symptoms resembled those often associated with common,mild infections.In summary,the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD.These models could serve as a basis for understanding the disease pathogenesis,conducting pre-trial prevention and evaluation,and implementing post-exposure intervention.

关键词： Coxsackievirus B3(CVB3) Hand foot and mouth disease(HFMD) Animal models Syrian hamster Rhesus monkey

Enhancing Strength-Ductility Synergy of CoCrNi-Based Medium-Entropy Alloy Through Coherent L1_(2)Nanoprecipitates and Grain Boundary Precipitates

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 78-88页

作者： Leilei Li Kaikai Song Qingwei Gao Changshan Zhou Xiaoming Liu Yaocen Wang Xiaojun Bai Chongde Cao School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an710016China Weihai research institute of Industrial Technology Shandong UniversityWeihai264209China research and development institute of Northwestern Polytechnical University in ShenzhenShenzhen518057China

The L1_(2)-strengthened Co_(34)Cr_(32)Ni_(27)Al_(4)Ti_(3)medium-entropy alloy(MEA)with precipitations of grain boundaries has been developed through selective laser melting(SLM)followed by cold rolling and annealing,exhibiting excellent strength-ductility synergy.The as-printed alloy exhibits low yield strength(YS)of~384 MPa,ultimate tensile strength(UTS)of~453 MPa,and uniform elongation(UE)of 1.5%due to the existence of the SLM-induced defects.After cold rolling and annealing,the YS,UTS,and UE are significantly increased to~739 MPa,~1230 MPa,and~47%,respectively.This enhancement primarily originates from the refined grain structure induced by cold rolling and annealing.The presence of coherent sphericalγ'precipitates(L1_(2)phases)and Al/Ti-rich precipitates at the grain boundaries,coupled with increased lattice defects such as dislocations,stacking faults,and ultrafine deformation twins,further contribute to the property’s improvement.Our study highlights the potential of SLM in producing high-strength and ductile MEA with coherent L1_(2)nanoprecipitates,which can be further optimized through subsequent rolling and annealing processes.These findings offer valuable insights for the development of high-performance alloys for future engineering applications.

关键词： Medium-entropy alloy Selective laser melting Precipitation Strength Ductility

Design of Resilient Sensor Networks Balancing Resilience and Efficiency

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International Journal of Disaster Risk Science 2024年第1期15卷 107-115页

作者： Sergey N.Vecherin Kiril D.Ratmanski Luke Hogewood Igor Linkov Cold Regions research and Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been developed and applied in many technical areas,becoming exceptionally pertinent to disaster risk science.During a disaster situation,accurate sensing information is the key to efficient recovery efforts.In general,resilience aims to minimize the impact of disruptions to systems through the fast recovery of critical functionality,but resilient design may require redundancy and could increase costs.In this article,we describe a method based on binary linear programming for sensor network design balancing efficiency with resilience.The application of the developed framework is demonstrated for the case of interior building surveillance utilizing infrared sensors in both twoand three-dimensional spaces.The method provides optimal sensor placement,taking into account critical functionality and a desired level of resilience and considering sensor type and availability.The problem formulation,resilience requirements,and application of the optimization algorithm are described in detail.Analysis of sensor locations with and without resilience requirements shows that resilient configuration requires redundancy in number of sensors and their intelligent placement.Both tasks are successfully solved by the described method,which can be applied to strengthen the resilience of sensor networks by design.The proposed methodology is suitable for large-scale optimization problems with many sensors and extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Redundant networks Resilience and efciency Resilient sensor networks

Examining the Spatiotemporal Dynamics and Determinants of Land Urbanization in Prefecture-level Cities,China

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Chinese Geographical Science 2024年第1期34卷 19-33页

作者： YANG Zhen ZHU Huxiao ZHANG Xinlin OU Xiangjun School of Geography Geomatics and Planning&Urban-rural Integration Development Research InstituteJiangsu Normal UniversityXuzhou221116China

Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change data and selected factors in 2010 and2020,this study used visual analysis to reveal the spatiotemporal dynamics of land urbanization across prefecture-level cities in China.Meanwhile,the driving forces underlying land urbanization were examined by using geographical detector technique.Following are the findings:1)we find that there exist notable spatial variances in land urbanization across prefecture-level cities.Currently,the differentiation in land urbanization between the northern and southern cities is more pronounced than that between the coastal and inland cities,or between the eastern and western cities.Prefecture-level cities located in central and western China have experienced the most rapid growth in land urbanization.Conversely,the growth rate in northeastern China is the lowest,while the velocity in eastern China remains relatively stable.By using spatial autocorrelation analysis,this study reveals that the land urbanization level in prefecture-level cities has significant spatial agglomeration.2)We further find that land urbanization in China is influenced by factors related to urban land supply and demand,and urban population growth,economic growth,land financial and political incentive have greater impact on land urbanization than other factors.3)We also find that the impacts of determinants on China’s land urbanization vary over time,the explanatory power of economic development increased,while the explanatory power of state forces declined.We argue that integrating the supply and demand factors of land urbanization can provide a more comprehensive understanding of the driving mechanisms underlying land urbanization in China and other transitional countries,and help decision-makers in these countries formulate more detailed and specific land urbanization policies.

关键词： land urbanization spatial pattern influencing factor geographical detector China

Resident immune responses to spinal cord injury:role of astrocytes and microglia

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Neural Regeneration research 2024年第8期19卷 1678-1685页

作者： Sydney Brockie Cindy Zhou Michael G.Fehlings Division of Genetics and development Krembil Research InstituteUniversity Health NetworkTorontoONCanada institute of Medical Science University of TorontoTorontoONCanada Division of Neurosurgery and Spine Program Department of SurgeryUniversity of TorontoTorontoONCanada

Spinal cord injury can be traumatic or non-traumatic in origin,with the latter rising in incidence and prevalence with the aging demographics of our society.Moreove r,as the global population ages,individuals with co-existent degenerative spinal pathology comprise a growing number of traumatic spinal cord injury cases,especially involving the cervical spinal cord.This makes recovery and treatment approaches particula rly challenging as age and comorbidities may limit regenerative capacity.For these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiology and the ensuing inflammatory response.This review discusses microglia-specific purinergic and cytokine signaling pathways,as well as microglial modulation of synaptic stability and plasticity after injury.Further,we evaluate the role of astrocytes in neurotransmission and calcium signaling,as well as their border-forming response to neural lesions.Both the inflammatory and reparative roles of these cells have eluded our complete understanding and remain key therapeutic targets due to their extensive structural and functional roles in the nervous system.Recent advances have shed light on the roles of glia in neurotransmission and reparative injury responses that will change how interventions are directed.Understanding key processes and existing knowledge gaps will allow future research to effectively target these cells and harness their regenerative potential.

关键词： astrocytes glial signaling microglia spinal cord injury synaptic transmission

Diagnosing ratio of electron density to collision frequency of plasma surrounding scaled model in a shock tube using low-frequency alternating magnetic field phase shift

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Chinese Physics B 2024年第5期33卷 519-530页

作者：吴明兴谢楷刘艳徐晗张宝田得阳 School of Aerospace Science and Technology Xidian UniversityXi'an 710071China Hypervelocity Aerodynamics institute China Aerodynamics Research and Development CenterMianyang 621000China

A non-contact low-frequency(LF)method of diagnosing the plasma surrounding a scaled model in a shock tube is proposed.This method utilizes the phase shift occurring after the transmission of an LF alternating magnetic field through the plasma to directly measure the ratio of the plasma loop average electron density to collision frequency.An equivalent circuit model is used to analyze the relationship of the phase shift of the magnetic field component of LF electromagnetic waves with the plasma electron density and collision frequency.The applicable range of the LF method on a given plasma scale is analyzed.The upper diagnostic limit for the ratio of the electron density(unit:m^(-3))to collision frequency(unit:Hz)exceeds 1×10^(11),enabling an electron density to exceed 1×10^(20)m^(-3)and a collision frequency to be less than 1 GHz.In this work,the feasibility of using the LF phase shift to implement the plasma diagnosis is also assessed.Diagnosis experiments on shock tube equipment are conducted by using both the electrostatic probe method and LF method.By comparing the diagnostic results of the two methods,the inversion results are relatively consistent with each other,thereby preliminarily verifying the feasibility of the LF method.The ratio of the electron density to the collision frequency has a relatively uniform distribution during the plasma stabilization.The LF diagnostic path is a loop around the model,which is suitable for diagnosing the plasma that surrounds the model.Finally,the causes of diagnostic discrepancy between the two methods are analyzed.The proposed method provides a new avenue for diagnosing high-density enveloping plasma.

关键词： low-frequency alternating magnetic field phase shift shock-tube plasma diagnosis electron density collision frequency

research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

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Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang Hai-bao Hu Liu-zhen Ren Lu-yao Bao Jun Wen Luo Xie School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China research and development institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial slippage.For now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement strategies.This paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of SHS.First,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular scale.Then,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving velocity.We proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on GLI.In addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI morphology.Finally,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction