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A study of the effect of local scour on the flow field near the spur dike

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 98-105页

作者： Yu-Tian Li jie-Min zhan Wing-Hong Onyx Wai Department of Industrial Design School of Industrial Design and Ceramic ArtFoshan UniversityFoshan 528000China Department of Applied Mechanics and Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

The flow field near a spur dike such as down flow and horseshoe vortex system(HVS)are susceptible to the topographic changes in the local scouring process,resulting in variation of the sediment transport with *** this study,large eddy simulations with fixed-bed at different scouring stages were conducted to investigate the changes in flow *** results imply that the bed deformation leads to an increase in flow rate per unit area,which represent the capability of sediment transportation by water,in the scour ***,the intensity of turbulent kinetic energy and bimodal motion near the sand bed induced by the HVS were also ***,the peak moments between the two sediment transport mechanisms were ***,understanding the complex feedback mechanism between topography and flow field is essential for the local scour problem.

关键词： Spur dike Local scour Large eddy simulation Down flow Horseshoe vortex system

Recent advances in Fe-N-C-and Co-N-C-based materials as bifunctional electrocatalysts for oxygen reduction and oxygen evolution

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Science China Chemistry 2024年第4期67卷 1137-1160页

作者： hui-Min Xu Hong-Rui Zhu Chen-Jin Huang Zhi-jie zhang Ting-Yu Shuai Qi-Ni zhan Gao-Ren Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts

Synthesis and optical properties of highly efficient Na_(3)KMg_(7)(PO_(4))_(6):Eu^(2+)blue phosphor for full-spectrum white-light-emitting diodes:The role of Li_(2)CO_(3)flux

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Journal of Rare Earths 2024年第7期42卷 1217-1223,I0001页

作者： Zihao Wang Sisi Liang Chenyang zhan Kunyuan Xu jie Hu Dejian Chen Liping Song Haomiao Zhu School of Physics and Materials Science Nanchang UniversityNanchang330000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China

Full-spectrum phosphor-converted white-light-emitting diodes(pc-WLED)are emerging as a mainstream technology in semiconductor ***,high-performance blue phosphor which can be excited efficiently by a 400 nm NUV diode chip is still ***,we present a blue-emitting Na_(3)KMg_(7)(PO_(4))6:Eu^(2+)phosphor synthesized by the solid-reaction ***,we find that the using of Li_(2)CO_(3)as flux can significantly improve the crystal quality and thus the emission efficiency of the ***,the excitation peak of the phosphor shifts from 365 to 400 nm,which is pivotal for efficient NUV(400 nm)diode chip *** practical Eu^(2+)concentration is also enhanced by using Li_(2)CO_(3)as flux,and the absorption efficiency is greatly *** phosphor exhibits superior PL thermal stability,namely retains 94%integrated photoluminescence intensity at 150℃of that at 25℃.As a result,the optimized phosphor shows an emission band peaked at 437 nm with a bandwidth of 40 nm and a high external photoluminescence quantum yield of 51.7%.Finally,a pc-WLED was fabricated by using NKMPO:Eu^(2+)blue,Sr_(2)SiO_(4):Eu^(2+)green,CaAlSiN_(3):Eu^(2+)red phosphors,and a 400 nm NUV diode *** shows a high color rendering index of R_(a)=96.4 and a correlated color temperature of 4358 *** results prove that NKMPO:Eu^(2+)is a promising blue phosphor for full-spectrum WLED based on NUV diode chips.

关键词： Eu^(2+) Blue phosphor Na_(3)KMg_(7)(PO_(4))_(6) Full-spectrum white LEDs Rare earths

Reducing the voltage loss of Y-series acceptor based organic solar cells via ternary/quaternary strategies

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Chinese Chemical Letters 2024年第2期35卷 70-86页

作者： Pengyu zhang Zhiyang zhang Heng Sun jie Li Yi Chen Jiang Wang Chuanlang zhan Key Laboratory of Advanced Materials Chemistry and Devices (AMC&DLab) of the Department of Education of Inner Mongolia Autonomous Region Inner Mongolia Key Laboratory of Green CatalysisCollege of Chemistry and Environment ScienceInner Mongolia Normal UniversityHuhehot 010022China

In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies (PCEs) of organic solar cells (OSCs) have exceeded 19%.However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of *** ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency *** this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.

关键词： Organic solar cell Ternary/quaternary strategy Open-circuit voltage Voltage loss Non-radiative recombination loss

Transforming Adolescent Smiles:Correcting Skeletal Mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners

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Current Medical Science 2024年第3期44卷 657-666页

作者： Wen-jie FAN Jia-qi zhanG Jia-qi zhan Li HU Li-li CHEN Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Stomatology Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Wuhan National High Magnetic Field Center Wuhan430074China The Affiliated Lianyungang Hospital of Xuzhou Medical University/The First People’s Hospital of Lianyungang Lianyungang222000China The First Affiliated Hospital of Kangda College of Nanjing Medical University/The First People’s Hospital of Lianyungang Lianyungang222000China

Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental *** traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial *** recent years,an invisible orthodontic technique,without brackets,has become increasingly ***,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect *** case report presents an adolescent patient with bimaxillary protrusion and mandibular *** on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular *** patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the *** case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction ***,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists.

关键词： mandibular retrusion esthetic orthodontic treatment clear aligners growth potential

Multiscale engineering of molecular electrocatalysts for the rapid hydrogen evolution reaction

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Nano Research 2024年第7期17卷 6026-6031页

作者： Huan Li zhan Jiang Yubo Yuan Yirong Tang jie Zao Wentao zhang Peiyi Han Xun zhang Bulin Chen Yongye Liang Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China South China Institute of Environmental Sciences Guangzhou 510655China

Molecular electrocatalysts have demonstrated potential for the hydrogen evolution reaction(HER)due to their well-defined structures and high intrinsic *** rapid production of hydrogen requires molecular electrocatalysts to operate at high current densities,which still presents a *** this work,we demonstrate that molecularly dispersed electrocatalysts of cobalt phthalocyanine anchored on carbon nanotubes(CoPc MDEs)are superior candidates due to the efficient charge transport between the substrate and the active *** intrinsic activity can be enhanced by introducing functional groups on *** facilitate mass transport,di(ethylene glycol)substituted CoPc molecules are further anchored on a threedimensional self-supported electrode(CoPc-DEG MDE@CC),enabling continuous operation for 25 h at−1000 mA/cm^(2)in 1.0 M *** study demonstrates the potential of molecular electrocatalysts for HER and emphasizes the importance of adjusting intrinsic activity,and charge and mass transport capacity for practical molecular electrocatalysts.

关键词： hydrogen evolution reaction cobalt phthalocyanine intrinsic activity mass transport

Rice planting acceleration of the activation and loss of soil iron in the red soil region of southern China

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Soil Ecology Letters 2024年第2期6卷 179-187页

作者： San’an Nie jie Fan Ningxiang Ouyang Hao Sheng Yangzhu zhang Xiong Yan zhan Yu College of Resources Hunan Agricultural UniversityChangsha410125China School of Economic Geography Hunan University of Finance and EconomicsChangsha410205China Zunyi Normal University Zunyi563006China

Rice planting decreased total iron but increased active *** activation varied greatly among different paddy soils but not in woodland *** soil iron was mainly affected by pH,SOC and particle *** decrease of soil Fe wa... 详细信息

关键词： paddy soil iron forms parent material rice planting Fe activation

AKT2^(S128)/CCTα^(S315/319/323)-positive cancer-associated fibroblasts (CAFs) mediate focal adhesion kinase (FAK) inhibitors resistance via secreting phosphatidylcholines (PCs)

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Signal Transduction and Targeted Therapy 2024年第2期9卷 782-796页

作者： jie Chen Lingyuan zhang Yuheng Zhu Di Zhao Jing zhang Yanmeng Zhu Jingyuan Pang Yuanfan Xiao Qingnan Wu Yan Wang Qimin zhan Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Laboratory of Molecular OncologyPeking University Cancer Hospital&Institute100142 BeijingChina Peking University International Cancer Institute Peking University100191 BeijingChina Research Unit of Molecular Cancer Research Chinese Academy of Medical SciencesBeijingChina Soochow University Cancer Institute Suzhou 215000China Institute of Cancer Research Shenzhen Bay LaboratoryShenzhen 518107China

Abnormal metabolism is regarded as an oncogenic hallmark related to tumor progression and therapeutic *** study employed multi-omics,including phosphoproteomics,untargeted metabolomics and lipidomics,to demonstrate that the pAKT2 Ser128 and pCCTαSer315/319/323-positive cancer-associated fibroblasts(CAFs)substantially release phosphatidylcholines(PCs),contributing to the resistance of focal adhesion kinase(FAK)inhibitors in esophageal squamous cell carcinoma(ESCC)***,we observed extremely low levels of FAK Tyr397 expression in CAFs,potentially offering no available target for FAK inhibitors playing their anti-growth role in ***,FAK inhibitor increased the intracellular concentration of Ca2+in CAFs,promoting the formation of AKT2/CCTαcomplex,leading to phosphorylation of CCTαSer315/319/323 sites and eventually enhancing stromal PC *** activation could stimulate the intratumoral Janus kinase 2(JAK2)/Signal transducer and activator of transcription 3(STAT3)pathway,triggering resistance to FAK *** of clinical samples demonstrated that stromal pAKT2 Ser128 and pCCTαSer315/319/323 are related to the tumor malignancy and reduced patient ***-targeted lipidomics and further validation cohort quantitatively showed that plasma PCs enable to distinguish the malignant extent of ESCC *** conclusion,inhibition of stroma-derived PCs and related pathway could be possible therapeutic strategies for tumor therapy.

关键词： CAFs metabolism resistance

Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore

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Transactions of Nonferrous Metals Society of China 2024年第9期34卷 2987-3001页

作者： Jia-qiao YUAN zhan DING Yun-xiao BI jie LI Shu-ming WEN Shao-jun BAI Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was *** effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical *** test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was *** ion concentration analysis results indicated that AMD facilitated desorption of Ca~(2+)and adsorption of Cu~(2+)on the depressed-pyrite *** measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S~0 hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of *** findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores.

关键词： copper sulfur ore acid mine drainage lime-depressed pyrite flotation natural activator activation mechanism