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A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun li Ming-Yi Wu Xu Han Si-Yuan He Ze-Yu lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation

Sesamin is an effective spleen tyrosine kinase inhibitor against IgE-mediated food allergy in computational， cell-based and animal studies

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Food Science and Human Wellness 2024年

作者： Yu li Xuerui Chen Longhua Xu Xintong Tan Dapeng li Dongxiao Sun-Waterhouse Feng li School of Chemical Sciences， The University of Auckland Key Laboratory of Food Nutrition and Human Health in Universities of Shandong College of Food Science and Engineering， Shandong Agricultural University

Food allergy has become a global concern. Spleen tyrosine kinase (SYK) inhibitors are promising therapeutics against allergic disorders. In this study， a total of 300 natural phenolic compounds were firstly subjected to virtual screening. Sesamin and its metabolites， sesamin monocatechol (SC-1) and sesamin dicatechol (SC-2)， were identified as potential SYK inhibitors， showing high binding affinity and inhibition efficiency towards SYK. Compared with R406 (a traditional SYK inhibitor)， sesamin， SC-1， and SC-2 had lower binding energy and inhibition constant (Ki) during molecular docking， exhibited higher bioavailability， safety， metabolism/clearance rate， and distribution uniformity ADMET predictions， and showed high stability in occupying the ATP-binding pocket of SYK during molecular dynamics simulations. In anti-dinitrophenyl-immunoglobulin E (Anti-DNP-IgE)/dinitrophenyl-human serum albumin (DNP-HSA)-stimulated rat basophilic leukemia (RBL-2H3) cells， sesamin in the concentration range of (5 – 80) μmol/L influenced significantly the degranulation and cytokine release， with 54.00% inhibition against β-hexosaminidase release and 58.45% decrease in histamine. In BALB/c mice， sesamin could ameliorate Anti-DNP-IgE/DNP-HSA-induced passive cutaneous anaphylaxis and ovalbumin (OVA)-induced active systemic anaphylaxis reactions， reduce the levels of allergic mediators (immunoglobulins and pro-inflammatory cytokines)， partially correct the imbalance of T helper (Th) cells differentiation in the spleen， and inhibit the phosphorylation of SYK and its downstream signaling proteins， including p38 mitogen-activated protein kinases (p38 MAPK)， extracellular signal-regulated kinases (ERK)， and p65 nuclear factor-κB (p65 NF-κB) in the spleen. Thus， sesamin may be a safe and versatile SYK inhibitor that can alleviate IgE-mediated food allergies.

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Regulation of photophysical and electronic properties of I-III-VI quantum dots for light-emitting diodes

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Science China Materials 2024年第9期67卷 2737-2748页

作者： Xiaofei Dong Xianggao li Shougen Yin Zheng li Longwu li Jingling li School of Science Langfang Normal UniversityLangfang 065000China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Institute of Material Physics Key Laboratory for Optoelectronic Materials and Devices of TianjinKey Laboratory of Display Materials and Photoelectric Devices of Ministry of EducationTianjin University of TechnologyTianjin 300384China College of Chemistry and Materials Science Langfang Normal UniversityLangfang 065000China School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China

Quantum dot light-emitting diodes(QLEDs)have become an important research direction in the pursuit of next-generation display technology owing to their favorable attributes,including high energy efficiency,wide color gamut,and low *** in the luminous efficiency and operating life of QLEDs have been achieved by enhancing the photoluminescence efficiency of the quantum dots(QDs)and optimizing the device ***,the current mainstream QDs contain heavy metal elements such as lead and cadmium,which restrict the development and application of QD *** new types of environmentally friendly QDs is crucial.I-III-VI semiconductor QDs have been developed as luminescent materials for constructing high color rendering index QLEDs,owing to the outstanding photophysical properties of these QDs,such as composition-dependent tunable bandgap,large Stokes shift,and highefficiency ***,the microstructures of heterojunctions,especially the surface states and interface states,affect the recombination and transport of carriers in electroluminescent(EL)devices with multilayer thin film structures,which in turn influence the luminous efficiency and stability of the *** review focuses on the synthesis strategies of I-III-VI multi-component QDs and provides an in-depth understanding of the luminescence mechanism and the regulation of photophysical and electronic ***,the application of I-III-VI QDs in multi-color and white EL QLEDs is discussed and the challenges and outlook are addressed.

关键词： Ⅰ-Ⅲ-Ⅵquantum dots synthesis method defect states luminescence mechanism light-emitting diodes

Inducible RNA targeting and N^(6)-methyladenosine editing by a split-Cas13 architecture

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Journal of Molecular Cell Biology 2024年第1期16卷 66-69页

作者： Yang li Qiang Sun Zhi Yang Gang Yuan International Institutes of Medicine the Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Department of Thoracic Surgery and Institute of Thoracic Oncology West China HospitalSichuan UniversityChengdu 610041China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Dear editor,Cas13,a class Ⅱ type Ⅵ CRISPR‒Cas endonuclease with two higher eukaryotes and prokaryotes nucleotide-binding(HEPN)domains,exclusively binds to and cleaves single-stranded RNA by a complementary guide RNA(gRNA)(Makarova et al.,2020).RfxCas13d(also known as CasRx)is an ortholog of CRISPR‒Cas13 with a relatively small size and robust RNA knockdown capability in mammalian cells(Konermann et al.,2018).Owing to its simplicity and high efficiency,CasRx has been applied for RNA targeting in various types of cells and ***,most of these studies failed to control the nuclease activity of CasRx *** re-engineered split-Cas9 system enables inducible genome editing and epigenetic modulation through chemical-induced reassembly of the Cas9 protein(Zetsche et al.,2015).However,tools that allow for efficient and controllable RNA knockdown by a split-Cas13 system remain to be established.

关键词： split system simplicity

The Impact of High-standard Free Trade Areas on the Diversification of China's Export Products: Expanding Market or Intensifying Competition?

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China & World Economy 2024年第4期32卷 33-67页

作者： Zhaobin Fan Ruimin Bian Hui li International Business School Jinan UniversityChina School of Management Jinan UniversityChina School of Mathematics University of BirminghamUK

In the context of China's efforts to establish a global network of free trade areas and diversify its export products, this study explores the impact of trade agreement depth on China's export diversification. Building upon a trade model with multiproduct firms, we discover that the effect of trade agreement depth on export diversification is multifaceted, depending on the relative magnitude of the “market expansion effect” and the “competition intensification effect.” Through empirical analysis of China's exports to 132 countries (or regions) from 2000 to 2015, we find that the deepening of trade agreements affected China's export diversification negatively. This negative correlation was predominantly due to the similarity in comparative advantages between China and its trade partners, leading to the “competition intensification effect” overshadowing the “market expansion effect.” We also note that “natural” agreements, when deepened, were more likely to affect China's export diversification adversely than their “non-natural” counterparts. Moreover, as export diversification increased, the marginal impact of deepening trade agreements exhibited an inverted U-shaped trajectory.

关键词： export product diversification export similarity high-standard free trad areas trade agreement depth

Two-dimensional C2N-based single-atom catalyst with complex microenvironment for enhanced electrochemical nitrogen reduction:A descriptor-based design

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Journal of Energy Chemistry 2024年第10期97卷 110-119页

作者： Enduo Dai Wei An Ruixian Guo Xugen Shi Yunyi li Yibo Wang Mingming liu College of Chemistry and Chemical Engineering Shanghai University of Engineering Science

The catalytic descriptor with operational feasibility is highly desired towards rational design of high-performance catalyst especially the electrode/electrolyte solution interface working under mild ***,we demonstrate that the descriptor Ω parameterized by readily accessible intrinsic properties of metal center and coordination is highly operational and efficient in rational design of single-atom catalyst（SAC） for driving electrochemical nitrogen reduction（NRR）.Using twodimensional metal（M）-BxPySzNm@C2N as prototype SAC models,we reveal that*N2+（H++e-）→*N2H acts predominantly as the potential-limiting step（PLS） of NRR on M-B2P2S2@C2N and M-B1P1S1N3@C2N regardless of the distinction in coordination *** the 28 screened M active sites,with Ω values close to the optimal 4,M-B2P2S2@C2N(M=V（Ω=3.53）,Mo（Ω=5.12）,and W（Ω=3.92）) and M-B1P1S1N3@C2N(M=V（Ω=3.00）,Mo（Ω=4.34）,and W（Ω=3.32）) yield the lowered limiting potential（UL） as-0.45,-0.54.-0.36,-0.58,-0.25,and-0.24 V,respectively,thus making them the promising NRR *** importantly,these SACs are located around the top of volcano-shape plot of ULversus Ω,re-validating Ω as an effective descriptor for accurately predicting the high-activity NRR SACs even with complex *** study unravels the relationship between active-site structure and NRR performance via the descriptor Ω,which can be applied to other important sustainable electrocatalytic reactions involving activation of small molecules via σ-donation and π*-backdonation mechanism.

关键词： Descriptor DFT Electrocatalysis N2 reduction Single-atom catalyst

Bile acid signaling in the regulation of whole body metabolic and immunological homeostasis

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Science China(life Sciences) 2024年第5期67卷 865-878页

作者： Wei Jia Yitao li Kenneth C.P.Cheung Xiaojiao Zheng School of Chinese Medicine Hong Kong Baptist UniversityHong KongChina Center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai JiaoTong University School of MedicineShanghai 200233China

Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune *** the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing *** allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune *** review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and *** BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.

关键词： bile acid whole body metabolism immunity

A universal cooperative assembly-oriented strategy for VS_(4) nanorod decoration on carbon nanostructures with enhanced magnesium storage properties

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Science China Chemistry 2024年第9期67卷 3153-3161页

作者： Yuehua Man An li Haowei Tang Jianlu Sun Yating Fei Yichen Du Xiaosi Zhou School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China

VS_(4) has a unique layered atomic chain structure and has the potential to become a high-performance cathode material of magnesium-ion batteries with a high capacity and long cycle ***,low conductivity and sluggish Mg^(2+)diffusivity during cycling limit its practical application in large-scale energy ***,a cooperative assembly-directed strategy is adopted to synthesize VS_(4) nanorods grown in situ on carbon nanotubes(CNTs/VS_(4)).VS_(4) nanorods are tightly anchored to CNTs through V-O-C interface covalent bonds,and CNTs can enhance the electronic conductivity of the *** addition,the ion insertion reaction using Mg^(2+)and Mg Cl^(+)as carriers reduces the polar barrier for divalent Mg^(2+)ion *** rationally designed architecture promotes ion diffusion and electron transfer,thus facilitating reaction *** cooperative assembly-oriented strategy can endow CNTs/VS_(4) with excellent magnesium storage properties,including a high reversible capacity of 223.2 m Ah g^(-1)at a current density of 50 m A g^(-1),a remarkable discharge capacity of 91.8 m Ah g^(-1)even at 2,000 m A g^(-1),and an impressive capacity retention of 85.2% after 1,000 cycles at 500 m A g^(-1).Moreover,this strategy can serve as a general synthetic method for the complexation of VS_(4) with other carbon nanostructures.

关键词： transition metal sulfides carbon nanostructure interfacial covalent bond magnesium-ion batteries cathode

Towards Blockchain-Based Secure BGP Routing,Challenges and Future Research Directions

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Computers, Materials & Continua 2024年第5期79卷 2035-2062页

作者： Qiong Yang li Ma Shanshan Tu Sami Ullah MuhammadWaqas Hisham Alasmary Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology North China University of TechnologyBeijing100144China Department of Computer Science Shaheed Benazir Bhutto UniversitySheringal18050Pakistan School of Computing and Mathematical Science Faculty of Engineering and ScienceUniversity of GreenwichLondonSE109LSUK School of Engineering Edith Cowan UniversityPerth6027Australia Department of Computer Science King Khalid UniversityAbha61421Saudi Arabia

Border Gateway Protocol(BGP)is a standard inter-domain routing protocol for the Internet that conveys network layer reachability information and establishes routes to different *** BGP protocol exhibits security design defects,such as an unconditional trust mechanism and the default acceptance of BGP route announcements from peers by BGP neighboring nodes,easily triggering prefix hijacking,path forgery,route leakage,and other BGP security ***,the traditional BGP security mechanism,relying on a public key infrastructure,faces issues like a single point of failure and a single point of *** decentralization,anti-tampering,and traceability advantages of blockchain offer new solution ideas for constructing secure and trusted inter-domain routing *** this paper,we summarize the characteristics of BGP protocol in detail,sort out the BGP security threats and their ***,we analyze the shortcomings of the traditional BGP security mechanism and comprehensively evaluate existing blockchain-based solutions to address the above problems and validate the reliability and effectiveness of blockchain-based BGP security methods in mitigating BGP security ***,we discuss the challenges posed by BGP security problems and outline prospects for future research.

关键词： BGP security blockchain prefix hijacking trust model secure routing