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Factors influencing methane diffusion behaviors in micro-nano coal pores: a comprehensive study

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Frontiers of Earth Science 2023年第1期17卷 71-86页

作者： Xianglong fang Dameng liu Yingfang zhou Xiaobo liu Yidong CAI School of Energy Resources China University of GeosciencesBeijing 100083China Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization China University of GeosciencesBeijing 100083China School of Engineering Fraser Noble BuildingKing's CollegeUniversity of AberdeenAB243UE AberdeenUK Postdoctoral Workstation of Applied Technology Research Institute Northeast Petroleum UniversityDaqing 163318China

Gas diffusion in the coal matrix plays a significant role in forecasting the production performance of coalbed methane(CBM)wells.To better understand methane diffusion behavior,a systematic study was performed on various rank coals with vitrinite reflectance(Ro,m)ranging from 0.46%to 2.79%.Multiple experiments,including coal petrographic analysis,field emission scanning electron microscopy(FESEM),low-temperature N2 adsorption/desorption,and mercury intrusion porosimetry(MIP),were conducted to quantitatively characterize the multiscale micro-nano pore system in different rank coals,which showed that the pore structure of coals exhibited a multimodal pore size and volume distribution.Isothermal adsorption-diffusion experiments using the volumetric method were also performed to understand the methane diffusion characteristics in the micro-nano pores of the coal reservoir.The applicability of the multiporous diffusion model is verified,and methane diffusion in the multi-scale pores of coal reservoirs exhibits the characteristics of early fast diffusion,transitional diffusion in the medium term,and slow diffusion in the later period.In addition,the factors affecting methane diffusion in coals were systematically analyzed,and gray relational analysis(GRA)was employed to analyze and identify the importance of these factors on methane diffusion.The results show the impact ranking of factors,in order from the most important to the least:particle size>moisture>surface area>pore volume>pressure>coal rank>temperature in all of three diffusion stages.These findings are helpful for forecasting production performance and enhancing the production efficiency of CBM.

关键词： coalbed methane reservoir micro-characteristic diffusion coefficient grey relational analysis

Survey and Tutorial on Hybrid Human-Artificial Intelligence

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Tsinghua Science and Technology 2023年第3期28卷 486-499页

作者： Feifei Shi fang zhou Hong liu Liming Chen Huansheng Ning School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Computer Science and Software Engineering East China Normal UniversityShanghai 200062China Faculty of Computing Ulster UniversityNewtownabbey BT370QBUK

The growing computing power,easy acquisition of large-scale data,and constantly improved algorithms have led to a new wave of artificial intelligence(AI)applications,which change the ways we live,manufacture,and do business.Along with this development,a rising concern is the relationship between AI and human intelligence,namely,whether AI systems may one day overtake,manipulate,or replace humans.In this paper,we introduce a novel concept named hybrid human-artificial intelligence(H-AI),which fuses human abilities and AI capabilities into a unified entity.It presents a challenging yet promising research direction that prompts secure and trusted AI innovations while keeping humans in the loop for effective control.We scientifically define the concept of H-AI and propose an evolution road map for the development of AI toward H-AI.We then examine the key underpinning techniques of H-AI,such as user profile modeling,cognitive computing,and human-in-the-loop machine learning.Afterward,we discuss H-AI’s potential applications in the area of smart homes,intelligent medicine,smart transportation,and smart manufacturing.Finally,we conduct a critical analysis of current challenges and open gaps in H-AI,upon which we elaborate on future research issues and directions.

关键词： hybrid human-artificial intelligence(H-AI) Internet of Things(IoT) artificial intelligence(AI)

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面向IC封装的机器视觉定位算法研究

制造业自动化 2014年第4期36卷 75-79页

作者：王娟方舟刘波张君安西安工业大学机电工程学院西安710032

在IC封装过程中,为了解决引线键合理论位置与实际位置不重合的问题,本文提出采用最小外接矩形拟合法求解芯片各个焊点和引线框架实际位置,实时校正在芯片引线键合工艺中由于贴片和装夹产生的位置误差。根据芯片引线键合批量化生产的特... 详细信息

在IC封装过程中,为了解决引线键合理论位置与实际位置不重合的问题,本文提出采用最小外接矩形拟合法求解芯片各个焊点和引线框架实际位置,实时校正在芯片引线键合工艺中由于贴片和装夹产生的位置误差。根据芯片引线键合批量化生产的特点分别建立软件的实验模块和批处理模块。在实验模块中,对芯片图像特征采用软件智能识别和人工辅助定义相配合的方法来实现芯片特征区域和类型的快速定义,形成与特定类型芯片相对应的特征信息文件和算法配置文件。在进行批量化生产时根据实验模块中建立的芯片特征和算法文件来进行焊点和引线框架的快速定位。这种方法在批处理运行时简化了算法的复杂度,提高了芯片焊点和引线框架的位置检测效率和引线键合质量。

关键词： IC封装引线键合位置误差智能识别人工辅助

Arbuscular Mycorrhizal Fungal Colonization at Different Succession Stages in Songnen Saline-Alkali Grassland

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Phyton-International Journal of Experimental Botany 2023年第1期92卷 297-310页

作者： Yajie liu Yunhui zhou Linlin fang Chunxue Yang College of Landscape Architecture Northeast Forestry UniversityHarbin150040China

Arbuscular mycorrhizal(AM)fungi can form symbiosis with 90%of the vascular plants and play important roles in ecosystem.To realize the AM fungal colonization at different succession stages in saline-alkali land and screen AM fungi species with great functions,roots and soil samples were collected from the three succession stages of Songnen saline-alkali grassland.The soil properties and AM fungal colonization were measured,and the fungus distributed extensively in three stages was annotated by sequencing for AML1/AML2 target,subsequently,maize was selected as the host to verify its colonization.The results showed that the soil properties improved with the succession of saline-alkali grassland.The plants’communities of the three stages could be colonized by AM fungi,and the colonization rate of Leymus chinensis(the third stage)ranged from 66.67%to 100%,Puccinellia tenuiflora(the second stage)ranged from 50%to 80%,while the Suaeda glauca(the first stage)was only 35%–60%.Glomeraceae sp1 was identified as the dominant AM fungi species which occurred frequently in the succession of saline-alkali land with the isolation frequency,relative abundance,and importance value of 100%,18.1%,and 59.1%,respectively.The colonization rate of Glomeraceae sp1 in maize ranged from 80%to 87%and similar mycorrhizal characteristics were detected in the roots of P.tenuiflora,S.glauca,and L.chinensis,indicating that Glomeraceae sp1 colonized the samples in the field.The correlation matrix indicated that colonization rate,colonization intensity,and vesicle abundance were closely related to soil conditions most,and they were related significantly to all the soil properties except cellulase activity.Besides,redundancy analysis(RDA)showed that soil properties drove the changes of AM fungal colonization and sporulation.These results will provide theoretical support for realizing the relationship between AM fungal colonization and soil conditions,and also for the exploration of AM fungi species with great functions.

关键词： Succession of saline-alkali land soil properties AM fungi colonization characteristics

Experimental Investigation and X-Ray Computed Microtomography Simulation on Thermal Physical Properties of Foundation Materials after Molten Salt Leakage in the Storage Tank

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Journal of Thermal Science 2024年第2期33卷 591-601页

作者： WANG Zhaowen zhou Hao LUO Jiawei LI Yawei fang Hao liu Tianxiao State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou310027China

This paper studied the thermal physical properties of foundation materials in the molten salt tank of thermal energy storage system after molten salt leakage by Transient plane source experiment and X-ray computed microtomography simulation methods.The microstructure,thermal properties and pressure resistance with different particle diameters were addressed.The measured heat conductivities from Transient plane source experiment for three cases are 0.49 W/(m·K),0.48 W/(m·K),and 0.51 W/(m·K),and the porosity is 30.1%,30.7%,and 31.2% respectively.The heat conductivity simulating results of three cases are 0.471 W/(m·K),0.482W/(m·K),and 0.513 W/(m·K).The ratio of difference between the results of simulation and Transient plane source measurement is as low as 1.2%,verifying the reliability of experimental and simulation results to a certain degree.Compared with the heat conductivity of 0.097-0.129 W/(m·K) and porosity of 71.6%-78.9% without leaking salt,the porosity is reduced by more than 50% while the heat conductivity increased by 4 to 5 times after molten salt leakage.This significant increase in heat conductivity has a great impact on security operation,structure design,and modeling of the tank foundation for solar power plants.

关键词： heat conductivity X-ray computed microtomography foundation materials three-phase threshold algorithm molten salt leakage

土壤氮水平对喜旱莲子草原产地和引入地基因型生长和防御的影响

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Journal of Plant Ecology 2022年第3期15卷 461-472页

作者： Mu liu fang zhou Xiaoyun Pan Zhijie Zhang Bo Li Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai 200438China Research Center for Ecology College of ScienceTibet UniversityLhasa 850000China Tibet University—Fudan University Joint Laboratory for Biodiversity and Global Change Fudan UniversityShanghai 200032China Ecology Department of BiologyUniversity of Konstanz78464 KonstanzGermany

同种植物生长在资源丰富生境中的个体,其防御水平被认为低于生长在资源匮乏生境中的个体。然而,生境的养分水平如何影响植物的诱导抗性和耐受性,以及这种影响在入侵植物的原产地和引入地种群间是否存在差异,目前均知之甚少。本研究以入... 详细信息

同种植物生长在资源丰富生境中的个体,其防御水平被认为低于生长在资源匮乏生境中的个体。然而,生境的养分水平如何影响植物的诱导抗性和耐受性,以及这种影响在入侵植物的原产地和引入地种群间是否存在差异,目前均知之甚少。本研究以入侵植物喜旱莲子草(Alternanthera philoxeroides)的原产地阿根廷和引入地美国的基因型为研究对象设计同质园实验,以探究土壤氮水平对植物的生长、组成和诱导性[莲草直胸跳甲(Agasicles hygrophila)取食诱导]化学防御以及耐受性的影响。实验中,我们测定了植物总生物量、伸长速率(生长速率的表征)以及叶片和根系中总碳、总氮和三萜皂苷(化学防御物质)的含量。研究结果显示,植物在低土壤氮水平下表现出较高的组成抗性(植物在低土壤氮水平下的叶片三萜皂苷含量高于其在高土壤氮水平的33%)和耐受性[植物被取食后总生物量下降的程度更低(植物在高土壤氮水平和低土壤氮水平下被取食后总生物量分别下降了24%和15%)],而在高土壤氮水平下表现出较高的诱导抗性(在高土壤氮水平下的植物被取食后叶片三萜皂苷含量与空白对照的植物相比升高了24%)。植物的组成抗性和耐受性与生长速率存在权衡,但诱导抗性与生长速率存在显著的正相关性。此外,引入地基因型在低土壤氮水平下叶片碳含量显著低于原产地基因型(-6%),但这种差异在高土壤氮水平下消失。这些结果表明,土壤氮水平影响植物对不同防御策略的选择偏好,并且在决定引入地基因型的表现时与植食作用存在交互作用。

关键词：喜旱莲子草(Alternanthera philoxeroides) 莲草直胸跳甲(Agasicles hygrophila) 生长-分化平衡假说表型可塑性植物-植食者互作关系植物入侵

A Theoretical Study on Transitional Shear Flow Behavior of the Compressible and Isothermal Thermoplastic Polymer

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Chinese Journal of Polymer Science 2019年第5期37卷 518-526页

作者： Dong-Lei liu Feng zhou Kun fang College of Mechanical and Electrical Engineering Nanchang University Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province Nanchang University

By extending the virtual conformational element of the polymer chain, a dynamic end-to-end(ETE) vector was presented to describe the chain's instantaneous morphology based on the spring-bead theory. A feasible viscoelastic model was proposed to describe the rheological behavior of the isothermal thermoplastic polymer materials, based on the molecular kinetics, thermodynamics, and continuum mechanics method. The model is simplified as the generalized Newton's law. Its integral formula with similar form to the KBKZ model was also derived. Rheological experiments were carried out with the isotactic polypropylene material. The experimental results reveal that the viscoelastic model exhibits a three-stage rheological characteristic. There is a distinct high-elastic rheological region in the middle stage, reflecting the pseudoplastic fluids properties. Compared with the Ostwald-de Waele power law model, the viscoelastic model shows a better agreement with the rheological practices.

关键词： Shear flow Theoretical model Thermoplastic polymer Rheological experiments

High cut-off membranes in patients requiring renal replacement therapy:a systematic review and meta-analysis

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Chinese Medical Journal 2023年第1期136卷 34-44页

作者： Zhifeng zhou Huang Kuang fang Wang Lu liu Ling Zhang Ping Fu Division of Nephrology Kidney Research InstituteWest China Hospital of Sichuan UniversityChengduSichuan 610041China Division of Nephrology Peking University First HospitalPeking University Institute of NephrologyKey Laboratory of Renal DiseaseMinistry of Health of ChinaBeijing 100034China Preventive Medicine West China School of Public HealthSichuan UniversityChengduSichuan 610041China

Background:Whether high cut-off(HCO)membranes are more effective than high-flux(HF)membranes in patients requiring renal replacement therapy(RRT)remains controversial.The aim of this systematic review was to investigate the efficacy of HCO membranes regarding the clearance of inflammation-related mediators,β2-microglobulin and urea;albumin loss;and all-cause mortality in patients requiring RRT.Methods:We searched all relevant studies on PubMed,Embase,Web of Science,the Cochrane Library,and China National Knowledge Infrastructure,with no language or publication year restrictions.Two reviewers independently selected studies and extracted data using a prespecified extraction instrument.Only randomized controlled trials(RCTs)were included.Summary estimates of standardized mean differences(SMDs)or weighted mean differences(WMDs)and risk ratios(RRs)were obtained by fixed-effects or random-effects models.Sensitivity analyses and subgroup analyses were performed to determine the source of heterogeneity.Results:Nineteen RCTs involving 710 participants were included in this systematic review.Compared with HF membranes,HCO membranes were more effective in reducing the plasma level of interleukin-6(IL-6)(SMD-0.25,95%confidence interval(CI)-0.48 to-0.01,P=0.04,I 2=63.8%);however,no difference was observed in the clearance of tumor necrosis factor-α(TNF-α)(SMD 0.03,95%CI-0.27 to 0.33,P=0.84,I 2=4.3%),IL-10(SMD 0.22,95%CI-0.12 to 0.55,P=0.21,I 2=0.0%),or urea(WMD-0.27,95%CI-2.77 to 2.23,P=0.83,I 2=19.6%).In addition,a more significant reduction ratio ofβ2-microglobulin(WMD 14.8,95%CI 3.78 to 25.82,P=0.01,I 2=88.3%)and a more obvious loss of albumin(WMD-0.25,95%CI-0.35 to-0.16,P<0.01,I 2=40.8%)could be observed with the treatment of HCO membranes.For all-cause mortality,there was no difference between the two groups(risk ratio[RR]1.10,95%CI 0.87 to 1.40,P=0.43,I 2=0.0%).Conclusions:Compared with HF membranes,HCO membranes might have additional benefits on the clearance of IL-6 andβ2-microglobulin but not on TNF-α,IL-10,and urea.

关键词： High cut-off High-flux Renal replacement therapy Randomized controlled trials Meta-analysis

Catalytic Pyrolysis of Soybean Oil with CaO/Bio-Char Based Catalyst to Produce High Quality Biofuel

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Journal of Renewable Materials 2022年第12期10卷 3107-3118页

作者： Lujiang Xu Geliang Xie Xianjun zhou Yucheng liu Zhen fang Biomass Group College of EngineeringNanjing Agricultural UniversityNanjing210031China

In this paper,CaO/bio-char was synthesized by directly co-pyrolysis of Ca(OH)_(2) and rice straw,and used as catalyst to catalytic pyrolysis of soybean oil to produce high quality biofuel.In this co-pyrolysis process,CaO particles has been successfully embedded on the bio-char surface.During the catalytic pyrolysis process,CaO/biochar showed a good catalytic performance on the deoxygenation of soybean oil.Pyrolysis temperature affected the pyrolysis reactions and pyrolytic products distributions dramatically,higher pyrolysis temperature lead to seriously cracking reactions,lower bio-oil yield and higher gases yield,and lower pyrolysis temperature lead to higher bio-oil yield with higher oxygenated compounds content and lower hydrocarbons contents,the suitable pyrolysis temperature was around 650℃.Under the optimal conditions(650℃ with WHSV at 6.4 h^(−1) and carrier gas flow rate at 100 ml/min),the selectivity(%)of hydrocarbons in the bio-oil was more than 90%.CaO/bio-char catalyst still shows good catalytic deoxygenation activity after 4 cycles.1 g of CaO/bio-char catalyst can catalyze pyrolysis of 32 g of soybean oil to produce high-quality liquid fuel.Bio-char based catalyst has been proved to be a promising catalyst for catalytic conversion of triglyceride-based lipids into high quality liquid biofuel.

关键词： Carbonization CaO/bio-char catalytic pyrolysis deoxygenation high quality biofuel