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Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： Peng-Cheng Wang Ming-Hui Chen Jim Jenkinson Yong-Xin Song Li Sun department of Mechanical engineering University of Houston Guren Nanomaterials department of Marine engineering Dalian Maritime University

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac) plugs during multi-stage hydraulic fracking. In practice sealing performances of such plugs are normally evaluated through pressure tests, and in numerical simulation studies, maximum contact stress, average contact stress and contact length data are used to determine sealing quality between a packer and casing. In previous studies, the impact of friction forces on sealing performance is often overlooked. This work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing performances. We first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac plug. Then we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution, deformation, and contact stress after setting. With the demonstration of validity of FEA method, we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress, average contact stress, contact stress distribution, and maximum mises stress for an actual packer used in plug products. In addition, we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial stress. This study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Sungai Lembing’s green tourism: Pioneering the future of resourcebased urban renewal

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The Innovation 2024年第2期5卷 19-20页

作者： Haoxuan Yu Ginura Gunaratna Izni Zahidi Chow Ming Fai department of Civil engineering School of EngineeringMonash University MalaysiaBandar SunwaySelangor 47500Malaysia

HOW DID SUNGAI LEMBING PAVE ITS PATH TO A GREEN EVOLUTION?Sungai Lembing,a resource-based town situated in Pahang,Malaysia,has historically positioned itself as a pivotal hub in the global tin mining sector.Geologically,Sungai Lembing’s history dates back to the Paleozoic and Mesozoic eras.These eras were marked by the closure of the Tethyan Ocean and the convergence of continental landmasses from the eastern part of the Gondwana continent.This complex geological background resulted in a wide variety of mineral resources.

关键词： situated eastern Pioneer

Structural engineering of BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures towards ultrastable and tunable photoluminescence

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Nano Research 2024年第3期17卷 1636-1645页

作者： Peng Liu Yan Xu Bohan Li Yuchi Zhang Hongzhou Lian Jun Lin department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China State Key Laboratory of Rare Earth resource Utilization Chang Chun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Construction of lead halide perovskite nanocrystals(LHP NCs)heterostructures is essential to obtain highly stable photoluminescence and expand their applications.Herein,a novel self-assembly strategy combining with a solvent-free thermal-assisted synthesis and a water-triggered reaction is developed to subsequently grow BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures at low nucleation temperature with high crystallinity.The as-obtained ternary BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures exhibit remarkably enhanced panchromatic emission and ultrastable luminescence ascribing to the low-defect growth based on lattice matching.Stable white light-emitting diodes(WLEDs)have been constructed with a high correlated color temperature(CCT)of 7225 K and luminous efficiency of 74.4 lm·W-1.Ln^(3+)-doped BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(Ln^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Sm^(3+),Yb^(3+)/Er^(3+))nanocomposites are further designed with excitation-dependent photoluminescence and thermochromic properties,making them excellent candidates for high-level anti-counterfeiting and encryption.This work offers a green and universal approach in assembling CsPbX_(3)(X=Cl,Br,I)on lattice-matched tungstate with adjustable panchromatic emission for versatile optical applications.

关键词： inorganic lead halide perovskites solvent-free synthesis panchromatic emission anti-counterfeiting and encryption application

Josephin domain containing 2(JOSD2)promotes lung cancer by inhibiting LKB1(Liver kinase B1)activity

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Signal Transduction and Targeted Therapy 2024年第2期9卷 693-708页

作者： Tao Yuan Chenming Zeng Jiawei Liu Chenxi Zhao Fujing Ge Yuekang Li Meijia Qian Jiamin Du Weihua Wang Yonghao Li Yue Liu Xiaoyang Dai Jianya Zhou Xueqin Chen Shenglin Ma Hong Zhu Qiaojun He Bo Yang Institute of Pharmacology&Toxicology Zhejiang Province Key Laboratory of Anti-Cancer Drug ResearchCollege of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Innovation Institute for Artificial Intelligence in Medicine Zhejiang UniversityHangzhou 311199China Ministry of Education Key Laboratory of Chinese Medicinal Plants resource from Lingnan Research Center of Medicinal Plants Resource Science and EngineeringGuangzhou University of Chinese MedicineGuangzhou 510006China Center for Drug Safety Evaluation and Research of Zhejiang University Hangzhou 310058China department of Respiratory Disease Thoracic Disease CenterThe First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310006China department of Oncology Hangzhou Cancer HospitalHangzhou 310002China Cancer Center of Zhejiang University HangzhouChina engineering Research Center of Innovative Anticancer Drugs Ministry of EducationHangzhouChina

Non-small cell lung cancer(NSCLC)ranks as one of the leading causes of cancer-related deaths worldwide.Despite the prominence and effectiveness of kinase-target therapies in NSCLC treatment,these drugs are suitable for and beneficial to a mere~30%of NSCLC patients.Consequently,the need for novel strategies addressing NSCLC remains pressing.Deubiquitinases(DUBs),a group of diverse enzymes with well-defined catalytic sites that are frequently overactivated in cancers and associated with tumorigenesis and regarded as promising therapeutic targets.Nevertheless,the mechanisms by which DUBs promote NSCLC remain poorly understood.Through a global analysis of the 97 DUBs’contribution to NSCLC survival possibilities using The Cancer Genome Atlas(TCGA)database,we found that high expression of Josephin Domain-containing protein 2(JOSD2)predicted the poor prognosis of patients.Depletion of JOSD2 significantly impeded NSCLC growth in both cell/patient-derived xenografts in vivo.Mechanically,we found that JOSD2 restricts the kinase activity of LKB1,an important tumor suppressor generally inactivated in NSCLC,by removing K6-linked polyubiquitination,an action vital for maintaining the integrity of the LKB1-STRAD-MO25 complex.Notably,we identified the first small-molecule inhibitor of JOSD2,and observed that its pharmacological inhibition significantly arrested NSCLC proliferation in vitro/in vivo.Our findings highlight the vital role of JOSD2 in hindering LKB1 activity,underscoring the therapeutic potential of targeting JOSD2 in NSCLC,especially in those with inactivated LKB1,and presenting its inhibitors as a promising strategy for NSCLC treatment.

关键词： LKB1 inhibiting removing

Utilizing dual-pathway energy transfer in upconversion nanoconjugates for reinforced photodynamic therapy

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Nano Research 2024年第4期17卷 2941-2948页

作者： Ruohao Zhang Yu Lu Yifei Zhou Kehong Lv Xinyu Fu Jitong Gong Shuang Yao Xiaozhen Wang Jing Feng Hongjie Zhang State Key Laboratory of Rare Earth resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei 230026China College of Chemistry Jilin UniversityChangchun 130012China department of Breast Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchun 130021China department of Chemistry Tsinghua UniversityBeijing 100084China

Enhancing the therapeutic effect of existing treatments or developing new non-invasive treatments are important measures to achieve high-efficiency treatment of malignant tumors.Photodynamic therapy(PDT)is an emerging treatment modality,and the key for achieving high-efficiency PDT is to select light with strong tissue penetration depth and enhance the generation of reactive oxygen species(ROS).Although the upconversion nanoparticles(UCNPs)modified with the photosensitizers could achieve PDT with strong penetration depth under near-infrared light irradiation,the ROS generated by traditional single-pathway PDT is still insufficient.Herein,we developed a novel nanoconjugate(UCNP-Ce6/AIEgen)for dual-pathway reinforced PDT,in which the UCNPs were co-modified with chlorin e6(Ce6)and luminogen with aggregation-induced emission(AIEgen).Due to the presence of AIEgen,UCNP-Ce6/AIEgen could avoid aggregation-caused luminescence quenching in biological water environments and convert upconversion luminescence(UCL)of UCNPs to Ce6-activatable fluorescence.Therefore,under the irradiation of 808 nm laser,UCNP-Ce6/AIEgen can not only undergo direct lanthanide-triplet energy transfer to activate Ce6,but also convert the UCL of UCNPs to the light that can activate Ce6 through Fӧrster resonance energy transfer to generate more ROS,thus promoting tumor cell apoptosis.This work broadens the applications of nanoconjugates of lanthanide-based inorganic materials and organic dyes,and provides a conception for reinforced PDT of tumors.

关键词： upconversion nanoparticle aggregation-induced emission direct lanthanide-triplet energy transfer Förster resonance energy transfer photodynamic therapy

Space/Air Covert Communications:Potentials,Scenarios,and Key Technologies

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China Communications 2024年第3期21卷 1-18页

作者： Mao Haobin Liu Yanming Zhu Lipeng Mao Tianqi Xiao Zhenyu Zhang Rui Han Zhu Xia Xianggen School of Electronic and Information engineering Beihang UniversityBeijing 100191China department of Electrical and Computer engineering National University of SingaporeSingapore 117583Singapore School of Science and engineering Shenzhen Research Institute of Big Datathe Chinese University of Hong KongShenzhenGuangdong 518172China department of Electrical and Computer engineering University of HoustonHoustonTX 77004USA department of Computer Science and engineering Kyung Hee UniversitySeoulSouth Korea446-701 department of Electrical and Computer engineering University of DelawareNewarkDE 19716USA

Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wireless propagation environment and the broad coverage pose severe threats to the protection of private data. Emerging covert communications provides a promising solution to achieve robust communication security. Aiming at facilitating the practical implementation of covert communications in space/air networks, we present a tutorial overview of its potentials, scenarios, and key technologies. Specifically, first, the commonly used covertness constraint model, covert performance metrics, and potential application scenarios are briefly introduced. Then, several efficient methods that introduce uncertainty into the covert system are thoroughly summarized, followed by several critical enabling technologies, including joint resource allocation and deployment/trajectory design, multi-antenna and beamforming techniques, reconfigurable intelligent surface(RIS), and artificial intelligence algorithms. Finally, we highlight some open issues for future investigation.

关键词： artificial intelligence(AI) sixth generation(6G) space-air-ground integrated networks(SAGINs) space/air covert communications

Engineered spidroin-derived high-performance fibers for diverse applications

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Nano Research 2024年第2期17卷 492-502页

作者： Dawen Qin Jingjing Li Huanrong Li Hongjie Zhang Kai Liu National-Local Joint engineering Laboratory for Energy Conservation in Chemical Process Integration and resources Utilization Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China State Key Laboratory of Rare Earth resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China engineering Research Center of Advanced Rare Earth Materials Ministry of EducationDepartment of ChemistryTsinghua UniversityBeijing 100084China University of Science and Technology of China Hefei 230026China

Spider silks are well known for their exceptional mechanical properties that are tougher than Kevlar and steel.However,the restricted production amounts from their native sources limit applications of spider silks.Over the decades,there have been significant interests in fabricating man-made silk fibers with comparable performance to natural silks,inspiring many efforts both for biosynthesizing recombinant spider silk proteins(spidroins)in amenable heterologous hosts and biomimetic spinning of artificial spider silks.These strategies provide promising routes to produce high-performance and functionally optimized fibers with diverse applications.Herein,we summarize the hosts that have been applied to produce recombinant spidroins.In addition,the fabrication and mechanical properties of recombinant spidroin fibers and their composite fibers are also introduced.Furthermore,we demonstrate the applications of recombinant spidroin-based fibers.Finally,facing the challenges in biosynthesis,scalable production,and hierarchical assembly of high-performance recombinant spidroins,we give a summary and perspective on future development.

关键词： spider silk recombinant spidroin heterologous expression fiber fabrication mechanical property

Translucent ceramic enabling next-generation lasing-driven near-infrared light source

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Science China Materials 2024年第4期67卷 1359-1360页

作者： Hongjie Zhang engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth resource Utilization Changchun Institute of Applied Chemistry(CIAC)Chinese Academy of Sciences(CAS)Changchun 130022China

Broadband near-infrared(NIR) light sources demonstrate great potential in quantitative food analysis, material identification,invasive brain imaging diagnosis, and real-time health monitoring fields, etc. [1–3]. Compared with competing technologies based on quantum dots and organic crystals, NIR-emitting phosphor converted light-emitting diodes(pc-LEDs) favor high spectral modulation and physicochemical stability [4].

关键词： light ceramic lasing

Robot-Oriented 6G Satellite-UAV Networks: Requirements, Paradigm Shifts, and Case Studies

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China Communications 2024年第2期21卷 74-84页

作者： Peng Wei Wei Feng Yunfei Chen Ning Ge Wei Xiang department of Electronic engineering Tsinghua UniversityBeijing 100084China department of engineering University of DurhamDH13LEDurhamUK School of Computing Engineering and Mathematical SciencesLa Trobe UniversityMelbourneVIC 3086Australia

Networked robots can perceive their surroundings, interact with each other or humans,and make decisions to accomplish specified tasks in remote/hazardous/complex environments. Satelliteunmanned aerial vehicle(UAV) networks can support such robots by providing on-demand communication services. However, under traditional open-loop communication paradigm, the network resources are usually divided into user-wise mostly-independent links,via ignoring the task-level dependency of robot collaboration. Thus, it is imperative to develop a new communication paradigm, taking into account the highlevel content and values behind, to facilitate multirobot operation. Inspired by Wiener’s Cybernetics theory, this article explores a closed-loop communication paradigm for the robot-oriented satellite-UAV network. This paradigm turns to handle group-wise structured links, so as to allocate resources in a taskoriented manner. It could also exploit the mobility of robots to liberate the network from full coverage,enabling new orchestration between network serving and positive mobility control of robots. Moreover,the integration of sensing, communications, computing and control would enlarge the benefit of this new paradigm. We present a case study for joint mobile edge computing(MEC) offloading and mobility control of robots, and finally outline potential challenges and open issues.

关键词： closed-loop communication mobility control satellite-UAV network structured resource allocation