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A Well Productivity Model for Multi-Layered Marine and Continental Transitional Reservoirs with Complex Fracture Networks

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1313-1330页

作者： Huiyan Zhao Xuezhong Chen Zhijian Hu Man Chen Bo Xiong jianying yang Sichuan Changning Natural Gas Development Company Limited PetroChina Southwest Oil and Gas Field CompanyYibin644399China Sichuan Shale Gas Exploration and Development Company Limited PetroChina Southwest Oil and Gas Field CompanyNeijiang641100China New Energy Division PetroChina Southwest Oil and Gas Field CompanyChengdu610051China

Using the typical characteristics of multi-layered marine and continental transitional gas reservoirs as a basis,a model is developed to predict the related well production rate.This model relies on the fractal theory of tortuous capillary bundles and can take into account multiple gas flow mechanisms at the micrometer and nanometer scales,as well as the flow characteristics in different types of thin layers(tight sandstone gas,shale gas,and coalbed gas).Moreover,a source-sink function concept and a pressure drop superposition principle are utilized to introduce a coupled flow model in the reservoir.A semi-analytical solution for the production rate is obtained using a matrix iteration method.A specific well is selected for fitting dynamic production data,and the calculation results show that the tight sandstone has the highest gas production per unit thickness compared with the other types of reservoirs.Moreover,desorption and diffusion of coalbed gas and shale gas can significantly contribute to gas production,and the daily production of these two gases decreases rapidly with decreasing reservoir pressure.Interestingly,the gas production from fractures exhibits an approximately U-shaped distribution,indicating the need to optimize the spacing between clusters during hydraulic fracturing to reduce the area of overlapping fracture control.The coal matrix water saturation significantly affects the coalbed gas production,with higher water saturation leading to lower production.

关键词： Marine-continental transitional reservoir multi-layered reservoir seepage mechanisms apparent permeability hydraulic horizontal well productivity model

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Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake

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Avian Research 2024年第2期15卷 187-195页

作者： Fucheng yang Mingqin Shao jianying Wang College of Life Science Jiangxi Normal UniversityNanchang330022China

Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks.

关键词： Climate change Extreme drought Foraging behavior Oriental stork Poyang lake

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Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives

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Defence Technology（防务技术） 2024年第3期33卷 270-277页

作者： Kun yang Lang Chen Danyang Liu Bin Zhang jianying Lu Junying Wu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant differences.However,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of microseconds.The present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of confinement.In this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water tank.Upon detonation,the gaseous products expand in one direction while forcing water ahead of them.The resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak camera.The shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation reaction.During the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release rate.This work demonstrates an effective means of evaluating the performance of aluminized explosives.

关键词： Aluminized explosive Non-ideal detonation Water push test Energy release

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Structural and Luminescent Properties of Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)Green-Emitting Transparent Ceramic Phosphor

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 533-540页

作者：郝留成 MIAO Xiaojun LI Kai ZHONG jianying 涂兵田 yang Zhangfu 王皓 Pinggao Group Co. LtdPingdingshan 467001China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 430070China School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001China

A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction route.The transparent ceramic phosphors were fabricated by pressureless sintering followed by hot-isostatic pressing(HIP).The crystal structure,luminescence and mechanical properties of the samples were systematically investigated.The transparent ceramic phosphors with tetrahedrally coordinated Mn^(2+)show strong green emission centered around 515 nm under blue light excitation.As the Mn^(2+)concentration increases,the crystal lattice expands slightly,resulting in a variation of crystal field and a slight red-shift of green emission peak.Six weak absorption peaks in the transmittance spectra originate from the spin-forbidden ^(4)T_(1)(^(4)G)→^(6)A_(1) transition of Mn^(2+).The decay time was found to decrease from 5.66 to 5.16 ms with the Mn^(2+)concentration.The present study contributes to the systematic understanding of crystal structure and properties of MgAlON:xMn^(2+)green-emitting transparent ceramic phosphor which has a potential application in high-power light-emitting diodes.

关键词： transparent ceramic phosphor green emission MgAlON photoluminescence

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Aero-structural design of joined-wing aircraft based on high-fidelity model

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Chinese Journal of Aeronautics 2024年第4期37卷 363-377页

作者： Cheng HE Fengjiang ZHAN Luchuang MA Gang CHEN jianying MA Unmanned Air Vehicle Research Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-sized UAV Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201108China

The joined-wing configuration reduces induced drag and structural weight by connecting the rear wing to the front wing.In addition,the rear wing can replace the role of the horizontal tail of a conventional aircraft,thus eliminating the aerodynamic drag and weight associated with the horizontal tail.This particular shape creates a highly coupled relationship between aerodynamics and structure,which must be fully considered during the overall design process to enhance aircraft performance.In this research,an aero-structural design model of the joined-wing aircraft is constructed based on high-fidelity computational fluid dynamics and structural finite element methods.The model is able to obtain accurate aerodynamic loads for the non-planar wing and to simulate the statically indeterminate structure of the closed wing configuration.The influence of the joined-wing shape parameters on the aerodynamic and structural disciplines,as well as the influence of geometric nonlinear characteristics,deformation constraints and buckling constraints on the structural weight are all taken into consideration.The model is applied to complete the aero-structural design optimization of a high-altitude long-endurance joined-wing aircraft,and wind tunnel tests are conducted.The test results verify the credibility of the design model proposed and the validity of the design environment.

关键词： Joined-wing configuration Aircraft design Aero-structural design Finite element Wind tunnel test

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The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function

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Journal of Integrative Agriculture 2024年第1期23卷 267-282页

作者： Qiao Li jianying Guo Han Zhang Mengxin Zhao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China College of Life Science Yangtze UniversityJingzhou 434025China

Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correl

关键词： plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities

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Effect of biochar application on rice,wheat,and corn seedlings in hydroponic culture

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Journal of Environmental Sciences 2024年第1期135卷 379-390页

作者： Yingjie Yin Jikai Li Sihang Zhu Qing Chen Chong Chen Yukui Rui jianying Shang College of Land Science and Technology China Agricultural UniversityKey Laboratory of Plant-Soil InteractionsMinistry of Educationand Key Laboratory of Arable Land Conservation in North ChinaMinistry of Agriculture and Rural AffairsBeijing 100193China Agricultural Management Institute Ministry of Agriculture and Rural AffairsBeijing 102208China College of Resources and Environmental Sciences China Agricultural UniversityBeijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationBeijing 100193China

In recent years,biochar has attracted considerable attention for soil quality improvement and carbon sequestration due to its unique physicochemical properties.However,the mechanism by which biochar application negatively affects the growth of crop seedlings has not been fully investigated.In this study,a hydroponic experiment was conducted to evaluate the response of rice,wheat,and corn seedlings to biochar application(CK,0 g/L;BC1,0.5 g/L;and BC2,1.0 g/L).Compared with the CK treatment,the BC1 and BC2 treatments decreased the fresh shoot and root weights of rice and corn seedlings(P0.05).For the contents of nutrient elements in seedlings,both BC1 and BC2 treatments hindered the roots from absorbing Fe and Cu and increased the uptake of Ca and Mn.Compared with the CK treatment,the translocation factor(TF)values of Ca,Mn,and Zn were significantly decreased especially in rice seedlings(35.3%-36.8%,68.7%-76.5%,and 29.8%-22.0%,respectively)under the BC1 and BC2 treatments,while only Mn was significantly decreased in wheat and corn seedlings(P<0.05).Transmission electron microscope(TEM)analysis of root cross-sections showed that nano-sized biochar particles(10~23 nm)were found in the root cells under BC2 treatment conditions.Our findings reveal that a large amount of biochar application can reduce nutrient absorption and translocation,and hinder rice,wheat,and corn seedlings,particularly rice seedling,in hydroponic system.

关键词： Biochar Toxicity Seedling growth Hydroponic cultivation

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Robust Distributed Model Predictive Control for Formation Tracking of Nonholonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 560-562页

作者： Zhigang Luo Bing Zhu jianying Zheng Zewei Zheng School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Dear Editor,This letter proposes a robust distributed model predictive control(MPC) strategy for formation tracking of a group of wheeled vehicles subject to constraints and disturbances. Formation control has attract... 详细信息

关键词： letter constraints searching

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Accelerated generation of holograms with ultra-low memory symmetrically high-compressed look-up table

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Chinese Physics B 2024年第4期33卷 466-471页

作者：杨燕朱建英孙敏远毕勇 Applied Laser Research Center Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents a hologram generation method,i.e.,a symmetrically high-compressed look-up table method,which can reduce memory usage by50%.In offline computing,half of the basic horizontal and vertical modulation factors are stored,halving the memory requirements without affecting inline speed.Currently,its potential extends to various holographic applications,including the production of optical diffraction elements.

关键词： computergenerated hologram look-up table holography

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Perinatal outcomes of re-recurrent gestational diabetes mellitus and their prognostic factors:A retrospective cohort study in China

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Chinese Medical Journal 2024年第4期137卷 499-501页

作者： Xia Xu Yanni Guo Tingting Liao Huale Zhang Rumeng Jiang Shuyao Huang jianying Yan Department of Obstetrics and Gynecology Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhouFujian 350001China

To the Editor:Gestational diabetes mellitus(GDM)is a pathologic condition in which glucose intolerance and insulin resistance develop to different degrees during pregnancy.Women with GDM have higher odds of adverse maternal and fetal outcomes.Patients with a history of GDM were at a significantly increased risk for recurrence of GDM in subsequent pregnancies.Our previous and some other studies found an increased incidence of adverse perinatal outcomes in pregnant with recurrent GDM.^([1])So far,women with a prior history of GDM are not recommended to refrain from subsequent pregnancy in light of the limited available data.What about those women with a history of recurrent GDM?Should women with recurrent GDM be recommended to avoid further pregnancy?Currently,studies on perinatal outcomes of women with re-recurrent GDM and their prognostic factors are very rare.Therefore,this retrospective cohort study was performed to explore perinatal outcomes of pregnant woman with re-recurrent GDM and their prognostic factors.

关键词： mellitus pregnancy diabetes

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