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Influence of high-Density Bedding Plane Characteristics on hydraulic Fracture Propagation in Shale Oil Reservoir

Computer Modeling in Engineering & Sciences 2024年第9期140卷 3051-3071页

作者： Xiao Yan Di Wang haitao yu State Key laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Beijing102206China State Energy Center for Shale Oil Research and Development Beijing102206China Department of Geotechnical Engineering College of Civil Engineering Tongji UniversityShanghai200092China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China Key laboratory of Deep Earth Science and Engineering(Sichuan University) Ministry of EducationChengdu610065China

The existence of high-density bedding planes is a typical characteristic of shale oil *** the behavior of hydraulic fracturing in high-density laminated rocks is significant for promoting shale oil *** this study,a hydraulic fracturing model considering tensile failure and frictional slip of the bedding planes is established within the framework of the unified pipe-interface element method(UP-IEM).The model developed for simulating the interaction between the hydraulic fracture and the bedding plane is validated by comparison with experimental *** hydraulic fracturing patterns in sealed and unsealed bedding planes are ***,the effects of differential stress,bedding plane permeability,spacing,and the friction coefficient of the bedding plane are *** results showed that a single main fracture crossing the bedding planes is more likely to form in sealed bedding planes under high differential *** decrease in bedding plane permeability and the increase in the friction coefficient also promote the fracture propagating perpendicular to the bedding *** with high-density bedding planes has a poorer fracturing effect than that with low-density bedding planes,as the hydraulic fracture is prone to initiate and propagate along the bedding ***,higher injection pressure is needed to maintain fracture propagation along the *** increase in bedding density will lead to a smaller fracturing *** fluid seepage into the bedding planes slows shale *** is recommended that increasing the injection flow rate,selecting alternative fracturing fluids,and employing multi-well/multi-cluster fracturing may be efficient methods to improve energy production in shale oil reservoirs.

关键词： hydraulic fracturing bedding planes shale unified pipe-interface element method

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low-Brightness Object Recognition Based on Deep learning

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Computers, Materials & Continua 2024年第5期79卷 1757-1773页

作者： Shu-Yin Chiang Ting-yu lin Department of Information and Telecommunications Engineering Ming Chuan UniversityTaoyuan City333Taiwan

This research focuses on addressing the challenges associated with image detection in low-light environments,particularly by applying artificial intelligence techniques to machine vision and object recognition *** primary goal is to tackle issues related to recognizing objects with low brightness *** this study,the Intel RealSense lidar Camera l515 is used to simultaneously capture color information and 16-bit depth information *** detection scenarios are categorized into normal brightness and low brightness *** the system determines a normal brightness environment,normal brightness images are recognized using deep learning *** low-brightness situations,three methods are proposed for *** first method is the SegmentationwithDepth image(SD)methodwhich involves segmenting the depth image,creating amask from the segmented depth image,mapping the obtained mask onto the true color(RGB)image to obtain a backgroundreduced RGB image,and recognizing the segmented *** second method is thehDVmethod(hue,depth,value)which combines RGB images converted to hSV images(hue,saturation,value)with depth images D to form hDV images for *** third method is the hSD(hue,saturation,depth)method which similarly combines RGB images converted to hSV images with depth images D to form hSD images for *** experimental results,in normal brightness environments,the average recognition rate obtained using image recognition methods is 91%.For low-brightness environments,using the SD method with original images for training and segmented images for recognition achieves an average recognition rate of over 82%.ThehDVmethod achieves an average recognition rate of over 70%,while the hSD method achieves an average recognition rate of over 84%.The hSD method allows for a quick and convenient low-light object recognition *** research outcome can be applied to nighttime surveillance systems or nighttime road safety systems

关键词： low-brightness depth image image segmentation image recognition hDV hSD

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Free amino group-directed C(sp^(2))-h arylation ofα-amino-β-aryl esters by palladium catalysis

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Chinese Chemical letters 2024年第2期35卷 358-360页

作者： yue Gao yu Du Weiping Su State Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science & Technology Innovation laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Native amino-directed palladium-catalyzed C(sp^(3))-h activation/functionalization has been developed for modification ofα-amino acids and *** a palladium(Ⅱ)-catalyzed C(sp^(2))-h arylation ofα-amino-β-aryl esters has been disclosed,using the native amino as the directing group.A variety of chiralα-amino-β-aryl esters can be functionalized to give the corresponding ortho-substituted mono-and di-arylated products.

关键词： Native amino-directed Palladium catalyst C(sp^(2))-h arylation α-Amino-β-aryl ester Chiralα-amino acid

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lactonization of dyes promoted by a coordination cage facilitates cavity-induced chromism as ion mobile detector

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Science China Chemistry 2024年第5期67卷 1554-1560页

作者： liangliang Zhang yu liang Zhifeng Xiao yuxuan Meng Jinyi huang Xi lin Ji li hong-Cai Zhou yu Fang Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal University and Strait Laboratory of Flexible Electronics(SLoFE)Fuzhou 350017China State Key laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Chemistry Texas A&M UniversityCollege StationTexas 77842-3012USA State Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Frontiers Science Center for Flexible Electronics(FSCFE) MIIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Polytechnical UniversityXi’an 710072China

Dye molecules often change colors(so-called “chromism”) according to the environment variation. however, they are rarely induced by a catalytic amount of cavity. Through encapsulation in the cavity of a porous coordination cage(PCC-2), Rhodamine B(1) is transformed from red quinonoid form(1q) into colorless lactone form(1l) in aprotic polar solutions. The μ4-Oh groups in the cavity of PCC-2 are shown to stabilize the uncommon zwitterion intermediate(1z), followed by converting to 1l, thus accelerating the equilibrium. The chromism is catalyzed by 0.25 mol% of PCC-2, and the reaction rate is improved by 80,400times. 1@PCC-2 can be further fabricated to a sol-gel that exhibits ion recognition properties. The resulting encapsulation and stabilization of an unconventional intermediate by a catalytic amount of the coordination cage provides fundamental insights into molecular isomerization and has potential use in chemical sensing.

关键词： porous coordination cage Zwitterion intermediate cavity Rhodamine B chromism

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Factors and Their Impact on Treatment Effect of Acupuncture in Different Outcomes:A Meta-Regression of Acupuncture Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2024年第3期30卷 260-266页

作者： XIU Wen-cui GANG Wei-juan ZhOU Qi ShI lan-jun hU Xiang-yu MING Tian-yu lUO Zhen ZhANG yu-qing JING Xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China China Center for Evidence-Based Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijing100700China Department of health Research Methods Evidenceand ImpactMcMaster UniversityHamiltonOntarioL8S 4L8Canada Center for Evidence-Based Integrative Medicine-Clarity Collaboration Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China

Background:The effects of acupuncture have varied in different randomized controlled trials(RCTs),and there are many factors that influence treatment effect of acupuncture in different outcomes,with conflicting ***:To identify factors and their impact on the treatment effect of acupuncture in different ***:Acupuncture RCTs were searched from 7 databases including Medline(Pub Med),Embase,Cochrane Central Register of Controlled Trials,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biology Medicine disc between January 1st,2015 and December 31st,*** studies must compare acupuncture to no acupuncture,sham acupuncture,or waiting lists,and report at least 1patient-important outcome.A multi-level meta-regression was conducted using a 3-level robust mixed model and univariate analyses were performed for all independent variables,even those excluded from the multivariable model due to *** used thresholds of 0.2 and 0.4 for the difference of standardized mean differences(SMDs),categorising them as small(large(>0.4) ***:The pain construct analysis involved 211 effect estimates from 153 studies and 14 independent ***-frequency acupuncture treatment sessions produced larger effects compared to low-frequency sessions [large magnitude,the difference of adjusted SMDs 0.46,95% confidence interval(CI) 0.07 to 0.84;P=0.02].The non-pain symptoms construct analysis comprised 323 effect estimates from 231 studies and 15 independent *** acupuncture showed moderately larger effects when compared to non-penetrating acupuncture(0.30,95% CI 0.06 to 0.53;P=0.01).The function construct analysis included 495 effect estimates from 274 studies and 14 independent *** acupuncture and the flexible acupuncture regimen showed moderately larger effects,compared to non-penetrating acupuncture and fixed regimen,respectively(0.40,95% CI 0

关键词： acupuncture randomized controlled trial patient-important outcome meta-regression

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Derivatives of Intersection local Time for Two Independent Symmetricα-stable Processes

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： huan ZhOU Guang Jun ShEN Qian yu Department of Mathematics Anhui Normal UniversityWuhu 241002P.R.China Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key laboratory of Mathematical Modelling and high Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and h?lder *** we show that this condition is also necessary for the existence of derivatives of intersection local time at the ***,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

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Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic h_(2)generation

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Nano Research 2024年第7期17卷 5835-5844页

作者： yu liu Yawen Shi hua Wang Shengbo Zhang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and Engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 20℃,PtCo_(2)@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 min−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2)***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2)nanocluster,which promotes the adsorption and activation of h_(2)O and AB molecules and accelerates hydrogen ***,PtCo_(2)@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

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A novel and promising engineering application of carbon dots:Enhancing the chloride binding performance of cement

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Chinese Chemical letters 2024年第6期35卷 409-416页

作者： Wu-Jian long Yang yu Chuang he Guangdong Provincial Key laboratory of Durability for Marine Civil Engineering Key Lab of Coastal Urban Resilient InfrastructureMOECollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Corrosion of reinforcement induced by chloride invasion is extensively considered as the dominating deterioration mechanism of reinforced concrete(RC)structures,leading to serious safety hazards and tremendous economic ***,it still lacks well dispersive and cost-efficient nanomaterials to improve the anti-chloride-corrosion ability of RC ***,specific carbon dots(CDs)with high dispersity and low cost are deliberately designed,successfully prepared by hydrothermal processing,and then firstly applied to immensely enhance chloride binding performance of cement,thereby contributing to suppressing the corrosion of ***,the tailored CDs are composed of the carbon core with highly crystalline sp^(2)C structures and oxygen-containing groups connecting on the carbon core;The typical equilibrium test confirms that with respect to that of the blank cement paste,the chloride binding capacity of cement paste involving 0.2 wt%(by weight of cement)CDs is increased by 109% after 14-day exposure to 3 mol/l Na Cl solution;according to comprehensive analyses of phase compositions,the chloride binding mechanism of CDs-modified cement is rationally attributed to the fact that the incorporation of CDs advances the formation of calcium silicate hydrate(C-S-h)gels and Friedel's salt(Fs),thus enormously enhancing the physically adsorbed and chemically bound chloride ions of cement *** work not only firstly provides a novel high-dispersity and low-cost nanomaterial toward the durability enhancement of RC structures,but also broadens the application of CDs in the field of engineering,conducing to stimulating their industrialization development.

关键词： Carbon dots Chloride binding Cement Chloride binding mechanism Friedel’s salt

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Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.Madhu h.C.Manjunatha N.Sowmya B.M.Rajesh l.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.l.Zhu S.M.Weng P.li X.F.li h.Ai h.R.Pan Z.M.Sheng Key laboratory for laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key laboratory of high Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

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