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Alkyl-modified nucleobases with 6/5/7/5 ring systems from the insect Cyclopelta parva

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Organic Chemistry Frontiers 2022年第1期9卷 75-80页

作者： Yong-Ming Yan Heng chen wen-long chen Dai-Wei Wang Li Liao Qing Lu Yong-Xian cheng Institute for Inheritance-Based Innovation of Chinese Medicine Marshall Laboratory of Biomedical EngineeringSchool of Pharmaceutical SciencesHealth Science CenterShenzhen UniversityShenzhen 518060PR China Guangdong Key Laboratory for Functional Substances in Medicinal Edible Resources and Healthcare Products School of Life Sciences and Food EngineeringHanshan Normal UniversityChaozhou 521041PR China

(±)-Cyclopeltains A and B(1 and 2),two pairs of unusual alkylated adenine derivatives,were isolated from the insect Cyclopelta parva and structurally characterized.1 and 2 both possess a 6/5/7/5 ring system arising from the alkylation of N^(7) and N^(10) by a C6 unit and the formation of a furan ring.A plausible biosynthetic pathway for 1 and 2 was *** evaluation of the enantiomers of 1 and 2 revealed that(−)-1 and(+)-2 could inhibit the production of TNF-αand IL-6 and the expression of iNOS,COX-2,and p-NF-κB.

关键词： ring bases structurally

Axial enantiomers with donor-regulated TADF feature for multicolor circularly polarized electroluminescence

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Science China Chemistry 2024年第6期67卷 2039-2045页

作者： chen-Hao Guo wen-long Zhao Ke-Ke Tan Wei-chen Guo Liheng Feng Chuan-Feng chen Meng Li School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan030006China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral *** pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide *** the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)***,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,*** results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor ***,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),*** convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.

关键词： axial chirality thermally activated delayed fluorescence circularly polarized luminescence electroluminescence organic light-emitting diodes

Learning the imaging mechanism directly from optical microscopy observations

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Photonics Research 2024年第1期12卷 7-26页

作者： ZE-HAO WANG long-KUN SHAN TONG-TIAN wenG TIAN-long chen XIANG-DONG chen ZHANG-YANG WANG GUANG-CAN GUO FANG-wen SUN CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China University of Texas at Austin AustinTexas 78705USA Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

The optical microscopy image plays an important role in scientific research through the direct visualization of the nanoworld,where the imaging mechanism is described as the convolution of the point spread function(PSF)and *** on a priori knowledge of the PSF or equivalent PSF,it is possible to achieve more precise exploration of the ***,it is an outstanding challenge to directly extract the PSF from microscopy ***,with the help of self-supervised learning,we propose a physics-informed masked autoencoder(PiMAE)that enables a learnable estimation of the PSF and emitters directly from the raw microscopy *** demonstrate our method in synthetic data and real-world experiments with significant accuracy and noise *** outperforms DeepSTORM and the Richardson–Lucy algorithm in synthetic data tasks with an average improvement of 19.6%and 50.7%(35 tasks),respectively,as measured by the normalized root mean square error(NRMSE)*** is achieved without prior knowledge of the PSF,in contrast to the supervised approach used by DeepSTORM and the known PSF assumption in the Richardson–Lucy *** method,PiMAE,provides a feasible scheme for achieving the hidden imaging mechanism in optical microscopy and has the potential to learn hidden mechanisms in many more systems.

关键词： optical emitter mechanism

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

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CHINESE JOURNAL OF POLYMER SCIENCE 2024年第8期42卷 1021-1028页

作者： Gong, Xue Xiao, Qin Li, Qing-Yin Liang, wen-Cui chen, Feng Li, long-Yu Ren, Shi-Jie Sichuan Univ Coll Polymer Sci & Engn State Key Lab Polymer Mat Engn Chengdu 610065 Peoples R China

Lithium-ion batteries (LIBs) benefit from an effective electrolyte system design in both terms of their safety and energy storage capability. Herein, a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer (PS-PEO-PS), resulting in a porous structure with good interconnections, which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes (GPEs). It has been demonstrated that post-cross-linking of the precursor membranes increases the rigidity of the nanofibers, which allows the polymer film to be dimensionally stable up to 260 degrees C while maintaining superior electrochemical properties. The obtained cross-linked GPEs (CGPEs) showed high ionic conductivity up to 4.53x10-3 Scm-1. With the CGPE-25, the assembled Li/LiFePO4 half cells exhibited good rate capability and maintained a capacity of 99.4% and a coulombic efficiency of 99.3% at 0.1 C. These results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance, particularly useful for Lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes Lithium-ion batteries MEMBRANE SEPARATOR STABILITY SIO2

Solidification behaviour and hot cracking susceptibility of a novel Ni-based superalloy

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Journal of Iron and Steel Research(International) 2024年第4期31卷 956-966页

作者： Yue chen Shao-min Lv Xing-fei Xie Xiao-can wen Jng-long Qu Jin-hui Du High-Temperature Materials Institute China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Beijing GAONA Materials and Technology Co. Ltd.Beijing 100081China Sichuan CISRI-GAONA Forging Co. Ltd.Deyang 610000SichuanChina

A novel Ni-based superalloy GH4151,with a γ′ volume fraction of about 55%and a service temperature capability up to 8oo oC,was *** to the different cooling conditions of various regions during the solidification of ingots,significant cooling rate variations may lead to the occurrence of hot *** scanning laser microscope was utilised to investigate the solidification process and phase precipitation behaviour of the GH4151 under wide range cooling *** characteristics of L→γ transformation were analysed,and the growth rates of at each stage were *** segregation behaviour was predicted using the Scheil equation,and the predicted results match well with the experimental *** sensitivity coefficient for hot cracking was modified,and cracking sensitivity coefficient values for the alloy under different cooling rates were computed,revealing that the alloy is most susceptible to hot cracking at 10℃/min cooling ***,controlling the cooling rate can reduce the possibility of hot cracking in ingot.

关键词： Ni-based superalloy Solidification behaviour In-situ observation Clyne and Davies's criterion:Hot cracking susceptibility

Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

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Photonics Research 2024年第3期12卷 444-455页

作者： wen-JIN ZHANG HAO-CHANG MO wen-JIE chen XIAO-DONG chen JIAN-wen DONG School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

Lenvatinib combined with sintilimab plus transarterial chemoembolization as first-line treatment for advanced hepatocellular carcinoma

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World Journal of Clinical Cases 2024年第2期12卷 285-292页

作者： Sha-Sha Sun Xiao-Di Guo wen-Dong Li Jing-long chen Department of Oncology Capital Medical University Affiliated Beijing Ditan HospitalBeijing 100015China

BACKGROUND Recently,combination therapy has shown a better trend towards improved tumour response and survival outcomes than monotherapy in patients with hepatocellular carcinoma(HCC).However,research on triple therapy[lenvatinib+sintilimab+transarterial chemoembolization(TACE)]as a first-line treatment for advanced HCC is *** To evaluate the safety and efficacy of triple therapy as a first-line treatment for advanced *** HCC patients with Barcelona Clinic Liver Cancer stage C treated with triple therapy were *** patients were treated with lenvatinib every day and sintilimab once every 3 ***,TACE was performed every 4-6 wk if *** primary outcome of the study was overall survival(OS).The secondary outcomes were the objective response rate(ORR),disease control rate(DCR),and incidence of adverse *** Forty HCC patients who underwent triple therapy were retrospectively analysed from January 2019 to January *** a median follow-up of 8.5 months,the 3-,6-,and 12-mo OS rates were 100%,88.5%,and 22.5%,*** ORR and DCR were 45%and 90%,*** median progressive free survival and median OS were not *** complications were observed in 76%of the patients(grade 3,15%;grade 4,2.5%).CONCLUSION Combination therapy comprising lenvatinib,sintilimab and TACE achieved promising outcomes in advanced HCC patients and had manageable effects.

关键词： Lenvatinib Sintilimab Advanced hepatocellular carcinoma Combination therapy Tumor response

Semi-supervised surface defect detection of wind turbine blades with YOLOv4

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Global Energy Interconnection 2024年第3期7卷 284-292页

作者： Chao Huang Minghui chen long Wang Department of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083P.R.China Shunde Innovation School University of Science and Technology BeijingFoshan 528399P.R.China

Timely inspection of defects on the surfaces of wind turbine blades can effectively prevent unpredictable *** this end,this study proposes a semi-supervised object-detection network based on You Only Looking Once version 4(YOLOv4).A semi-supervised structure comprising a generative adversarial network(GAN)was designed to overcome the difficulty in obtaining sufficient samples and sample *** a GAN,the generator is realized by an encoder-decoder network,where the backbone of the encoder is YOLOv4 and the decoder comprises inverse convolutional *** features from the generator are passed to the defect detection *** several unlabeled images can significantly improve the generalization and recognition capabilities of defect-detection *** small-scale object detection capacity of the network can be improved by enhancing essential features in the feature map by adding the concurrent spatial and channel squeeze and excitation(scSE)attention module to the three parts of the YOLOv4 network.A balancing improvement was made to the loss function of YOLOv4 to overcome the imbalance problem of the defective *** results for both the single-and multi-category defect datasets show that the improved model can make good use of the features of the unlabeled *** accuracy of wind turbine blade defect detection also has a significant advantage over classical object detection algorithms,including faster R-CNN and DETR.

关键词： Defect detection Generative adversarial network scSE attention Semi-supervision Wind turbine