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Study of the Transport Behavior of Mul.ispherical Proppant in intersecting Fracture Based on Discrete Element Method

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Energy Engineering 2025年第1期122卷 185-201页

作者： Chengyong peng JianshuWu Mao Jiang Biao Yin Yishan lou CNOOC Research institute Company limited Beijing100028China School of Petroleum Engineering Yangtze UniversityWuhan430100China Hubei Key laboratory of Oil and Gas Dril.ing and Production Engineering(Yangtze University) Wuhan430100China

To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on *** reservoir production parameters and the discrete elementmethod,mul.ispherical proppants were ***,a 3D fracture model,based on the specified conditions of the l block,employed coupled(Computational Fl.id Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of mul.ispherical proppants in intersecting *** indicate that turbulent kinetic energy is an intrinsic factor affecting proppant ***,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture *** to small-angle fractures,control.ing artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by control.ing the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures.

关键词： Hydraulic fracturing discrete element method proppant sphericity CFD-DEM

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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin peng Yu Bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research institute of Mul.idisciplinary Science Beijing Institute of Technology Beijing Key laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysul.ides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μl mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

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low-cost and fluoride-free synthesis of MFi zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFi zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive coll.idal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 l highpressure autoclave, yiel.ing samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFi nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： Aspect ratio

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Preparation of Modified Composite Nanofiltration Membrane Synergistically Using Carboxylic Mul.i- walled Carbon Nanotube and β-cyclodextrin

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 232-239页

作者： liU peng MAO Junpeng FANG Yanfeng YU Yunwu CHEN Changxiu TANG Ning WAN Ye GU Yaxin liU Yunxue WANG lihua School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China

A new modified blend ultrafiltration(UF)membrane with good hydrophilicity,high porosity and excellent anti-fouling performance was developed by using carboxylic mul.i-walled carbon nanotube(CMWCNT)as casting solution ***,a composite nanofiltration(NF)membrane with large water flux and good retention rate was fabricated by using the PVDF/CMWCNT blend UF membrane as the substrate,and polyvinyl alcohol(PVA),β-cyclodextrin(β-CD)and polyethylenimine(PEi)as the coating *** results show that with the appropriate addition of CMWCNT in the casting solution,the surface roughness,porosity and recovery rate of the PVDF/CMWCNT blend UF membrane is obviously *** water flux of blend UF membrane is significantly improved when the CMWCNT content increases from 0 wt%to 0.2 wt%.The water flux of blend UF membrane with 0.2 wt%CMWCNT is 162.7 l/(m^(2)·h),which is 44.3%higher than that of the pure PVDF ***β-CD content is 0.8 wt%,the retention rate of Congo red by PVDF/CMWCNT/β-CD composite NF membrane reaches 98.7%,which is 28.3%higher than that of single PVA/PEi modified *** research will provide a new idea and simple method for developing novel high-performance composite NF membranes.

关键词： CMWCNT cyclodextrin nanofiltration membrane

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FHl2 deficiency aggravates Candida al.icans infection through decreased myelopoiesis

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Science China life Sciences 2025年

作者： Rongmei Gao Kanchao Chen Yimin Wang Rongxia Guo Xiaoyu Zhang peng Wu Weili Wang Qingxiang Huang Xuemei Xie Shangda Yang Yanling lü Qian Ren Fei liu Song Chen Fengxia Ma Tao Cheng Hui Cheng State Key laboratory of Experimental Hematology National Clinical Research Center for Blood Diseases Haihe Laboratory of Cell Ecosystem Institute of Hematology & Blood Diseases Hospital Chinese Academy of Medical Sciences & Peking Union Medical College CAMS Center for Stem Cell Medicine PUMC Department of Stem Cell and Regenerative Medicine

Hematopoiesis is a finely tuned process that generates all blood cell types through self-renewal and differentiation, which is crucial for maintaining homeostasis. Acute infections can prompt a hematopoietic response known as emergency myelopoiesis. in this study, using a Candida al.icans (C. al.icans) infection model, we demonstrated for the first time that disruption of Fhl2 led to increased fungal burden,heightened inflammatory response and reduced survival rates. impaired myel.id hematopoiesis and immune cell production were evident, as proved by the decreased numbers of hematopoietic stem and progenitor cells (HSPCs) and granulocytes in the bone marrow of Fhl2-deficient mice. in conclusion, FHl2 regulated emergency myelopoiesis in response to C. al.icans, affecting the host’s defense against pathogens.

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Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第01期 297-307页

作者： Bin Fang limin Wang Haoqin li Jiaxin Zhang Yang Ding Pan Pan li Bo peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University institute of Flexible Electronics (iFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HiRi） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HiRi. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. in this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial.identification to track the fluctuates of mtH2O2in HiRi. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural.illumination microscopy（SiM）, enabling high-quality mitochondrial.imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HiRi. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HiRi, which triggered mitophagy deficiency and led to cell death. in conclusion, Mito-WG possesses excellent photophysical and low-background properties for SiM imaging, making it a promising tool for mtH2O2tracking in HiRi research and clinical diagnosis.

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improved data gap-fil.ing schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： ZHAO peng Johannes lüERS Department of Micrometeorology University of Bayreuth institute of Ecology University of Innsbruck Member of Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. in this study we developed a modified gap-fil.ing scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was expl.ined as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-fil.ing Net ecosystem exchange l.i

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Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology research 2025年第1期33卷 103-121页

作者： Yan lu Kang Wang Yuanhong peng Meng Chen lin Zhong luji Huang F U Cheng Xindan Sheng Xin Yang Manzhao Ouyang George A Calin Zhiwei He China-America Cancer Research institute Guangdong Medical University Dongguan 523808 China. GCP Center Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. Department of Gastrointestinal Surgery Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. The Second School of Clinical Medicine Southern Medical University Guangzhou 510080 China. Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer Center Houston TX 77030 USA. Department of Oncology Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China.

Background:immune checkpoint inhibitors play an important role in the treatment of solid tumors, but the currently used immune checkpoint inhibitors targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-l1), and cytotoxic T-lymphocyte antigen-4 (CTlA-4) show limited clinical efficacy in many breast cancers. B7H3 has been widely reported as an immunosuppressive molecule, but its immunological function in breast cancer patients remains unclear.Methods:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program (TCGA) and the Gene Expression Omnibus (GEO) databases. MicroRNAs were selected using the TarBase, miRTarBase, and miRBase databases. The regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays, which identified the specific action sites of interaction. The expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR (qPCR). experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and apoptosis. Additionally, the regulatory impact of hsa-miR-214-3p on B7H3 was examined. Enzyme-linked immunosorbent assays (EliSA) and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells (PBMCs) on immune cells and associated cytokines.Results:in breast cancer tissues, the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p, as well as with the regulatory effects on breast cancercell behavior. Hsa-miR-214-3p was found to inhibit breast cancer cell growth by downregulating B7H3. importantly, our research identified, for the first time, two binding sites for hsa-miR-214-3p on the 3' UTR of B7H3, both of which exert similar effects independently. Co-culture experime

关键词： B7H3 Breast cancer Hsa-miR-214-3p immunotherapy

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[Construction of a 17 β-estradiol sensor based on a magnetic graphene oxide/aptamer separating material]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 87-95页

作者： Xin-Yu Jin le-Yuan Chen Ya-Nna liu Wen-Jing Xie Han-Yong peng State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. University of Chinese Academy of Sciences Beijing 100049 China. School of Environment Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou 310024 China.

17-Estradiol (E2) is a natural steroidal estrogen essential for a variety of physiological functions in organisms. However, external E2, which is renowned for its potent biological effects, is also considered to be an endocrine-disrupting compound (EDC) capable of disturbing the normal operation of the endocrine system, even at nanogram-per-liter (ng/l) concentrations. Studies have revealed that medical and livestock wastewater can be contaminated with E2, which poses potential risks to human health. Currently, the primary method for detecting E2 relies on liquid chromatography-mass spectrometry, which is limited with regard to on-site or large-scale sample testing due to instrumental constraints. Herein, we developed a magnetic graphene oxide (MGO)/aptamer separating material. The MGO was synthesized by creating a water-in-oil microemul.ion at 90 ℃, an agarose hydrogel to load the FeO nanoparticles, and layered graphene oxide (GO). in contrast to conventional methods, such as chemical co-precipitation and solvothermal approaches, this method is more time-efficient and does not require high temperature or pressure. Moreover, the use of a physical encapsulation technique for enwrapping the FeO nanoparticles and layered GO eliminates the need for chemical modification. This approach reduces the use of harmful chemicals, ensures complete loading, and results in highly efficient encapsulation. The MGO was characterized using Fourier-transform infrared (FT-iR) spectroscopy and transmission electron microscopy (TEM), as well as dynamic light scattering (DlS) and Zeta potential analyses, which revealed that the FeO nanoparticles had been successfully loaded onto the GO to produce MGO particles mainly around 5 μm in size. Additionally, this study demonstrated that the aqueous MGO dispersion is highly stable. This substance was used to develop a fluorescent biosensor that uses a "turn-on" mechanism to rapidly and highly sensitively detect E2. MGO is capable of adsorbing a fl

关键词： 17-estradiol (E2) fluorescence biosensor magnetic graphene oxide (MGO) magnetic solid phase separation

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Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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iEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma peng Jin Frank l.lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research institute University of Texas at ArlingtonFort WorthTexas 76118 USA iEEE

in this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

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