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A compact fluorescence/circular dichroism dual-modality probe for detection, differentiation, and detoxification of multiple heavy metal ions via bond-cleavage cascade reactions 被引量:2
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作者 Junwei Chen Na Wang +7 位作者 Hongjuan Tong Chao Song Huijuan Ma Yajun Zhang Feng Gao Huan Xu Wei Wang Kaiyan Lou 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第12期3876-3881,共6页
Selective detection of multiple analytes in a compact design with dual-modality and theranostic features presents great challenges. Herein, we wish to report a coumarin-thiazolidine masked D-penicillamine based dual-m... Selective detection of multiple analytes in a compact design with dual-modality and theranostic features presents great challenges. Herein, we wish to report a coumarin-thiazolidine masked D-penicillamine based dual-modality fluorescent probe COU-DPA-1 for selective detection, differentiation, and detoxification of multiple heavy metal ions(Ag^(+), Hg^(2+), Cu^(2+)). The probe shows divergent fluorescence(FL)/circular dichroism(CD) responses via divergent bond-cleavage cascade reactions(metal ion promoted C-S cleavage and hydrolysis at two distinctive cleavage sites): FL “turn-off” and CD “turn-on” for Ag+(no hydrolysis), FL “turn-on” and CD “turn-off” for Hg^(+)(imine hydrolysis), and FL “self-threshold ratiometric” and CD “turn-off” for excess Cu^(2+)(lactone and imine hydrolysis), providing the first example of a fluorescence/CD dual-modality probe for multiple species with complimentary responses. Moreover, the bond-cleavage cascade reactions also lead to the formation of D-penicillamine heavy metal ion complexes for potential detoxification treatments. 展开更多
关键词 Fluorescent probe Circular dichroism Heavy metal ions dual-modality DETOXIFICATION Cascade reaction Divergent responses
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FOLATE-TARGETED OPTICAL AND MAGNETIC RESONANCE DUAL-MODALITY PCL-b-PEG MICELLES FOR TUMOR IMAGING 被引量:1
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作者 唐建斌 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第4期427-430,共4页
A biodegradable tumor targeting nano-probe based on poly(ε-caprolactone)-b-poly(ethylene glycol) block copolymer (PCL-b-PEG)micelle functionalized with a magnetic resonance imaging (MRI) contrast agent diethy... A biodegradable tumor targeting nano-probe based on poly(ε-caprolactone)-b-poly(ethylene glycol) block copolymer (PCL-b-PEG)micelle functionalized with a magnetic resonance imaging (MRI) contrast agent diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd+) on the shell and a near-infrared (NIR) dye in the core for magnetic resonance and optical dual-modality imaging was prepared. The longitudinal relaxivity (rl) of the PCL-b-PEG- DTPA-Gd3+ micelle was 13.4 (mmol/L)^-1s^-1, three folds of that of DTPA-Gd3+, and higher than that of many polymeric contrast agents with similar structures. The in vivo optical imaging of a nude mouse bearing xenografied breast tumor showed that the dual-modality micelle preferentially accumulated in the tumor via the folic acid-mediated active targeting and the passive accumulation by the enhanced permeability and retention (EPR) effect. The results indicated that the dualmodality micelle is a promising nano-probe for cancer detection and diagnosis. 展开更多
关键词 dual-modality Polymeric micelle MRI contrast agent FLUORESCENCE Tumor imaging.
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Comparison of the clinical effects of dual-modality endoscopy and traditional laparotomy for the treatment of intra-and extrahepatic bile duct stones 被引量:2
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作者 Wei Wang Hui Xia Bin Dai 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期759-767,共9页
BACKGROUND Bile duct stones(BDSs)may cause patients to develop liver cirrhosis or even liver cancer.Currently,the success rate of surgical treatment for intrahepatic and extrahepatic BDSs is not satisfactory,and there... BACKGROUND Bile duct stones(BDSs)may cause patients to develop liver cirrhosis or even liver cancer.Currently,the success rate of surgical treatment for intrahepatic and extrahepatic BDSs is not satisfactory,and there is a risk of postoperative complic-ations.AIM To compare the clinical effects of dual-modality endoscopy(duodenoscopy and laparoscopy)with those of traditional laparotomy in the treatment of intra-and extrahepatic BDSs.METHODS Ninety-five patients with intra-and extrahepatic BDSs who sought medical services at Wuhan No.1 Hospital between August 2019 and May 2023 were selected;45 patients in the control group were treated by traditional laparotomy,and 50 patients in the research group were treated by dual-modality endoscopy.The following factors were collected for analysis:curative effects,safety(incision infection,biliary fistula,lung infection,hemobilia),surgical factors[surgery time,intraoperative blood loss(IBL)volume,gastrointestinal function recovery time,and length of hospital stay],serum inflammatory markers[tumor necrosis factor(TNF)-α,interleukin(IL)-6,and IL-8],and oxidative stress[glutathione peroxidase(GSH-Px),superoxide dismutase(SOD),malondialdehyde(MDA),and advanced protein oxidation products(AOPPs)].RESULTS The analysis revealed markedly better efficacy(an obviously higher total effective rate)in the research group than in the control group.In addition,an evidently lower postoperative complication rate,shorter surgical duration,gastrointestinal function recovery time and hospital stay,and lower IBL volume were observed in the research group.Furthermore,the posttreatment serum inflammatory marker(TNF-α,IL-6,and IL-8)levels were significantly lower in the research group than in the control group.Compared with those in the control group,the posttreatment GSH-Px,SOD,MDA and AOPPs in the research group were equivalent to the pretreatment levels;for example,the GSH-Px and SOD levels were significantly higher,while the MDA and AOPP levels were lower.CONCLUSION Dual-modality endoscopy therapy(duodenoscopy and laparoscopy)is more effective than traditional laparotomy in the treatment of intra-and extrahepatic BDSs and has a lower risk of postoperative complications;significantly shortened surgical time;shorter gastrointestinal function recovery time;shorter hospital stay;and lower intraop-erative bleeding volume,while having a significant inhibitory effect on excessive serum inflammation and causing little postoperative oxidative stress. 展开更多
关键词 dual-modality endoscopy Traditional laparotomy Intra-and extrahepatic bile duct stones Clinical efficacy
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IN VIVO VALIDATION OF DUAL-MODALITY SYSTEM FOR SIMULTANEOUS POSITRON EMISSION TOMOGRAPHY AND OPTICAL TOMOGRAPHIC IMAGING
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作者 XIN WANG BIN ZHANG +4 位作者 XU CAO FEI LIU SHUANGQUAN LIU BAOCI SHAN JING BAI 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第2期165-171,共7页
We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast canc... We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast cancer cells which expressed redfluorescent protein(RFP).For FMT system,reflective illumination mode was adopted with full-angle data acquisition.[18F]-Fluorodeoxyglucose([18F]-FDG)was used as radioactive tracer for PET.Both data were acquired simultaneously and then reconstructed separately before fusion.Fluorescent tomography results showed exactly where the tumor was located while PET results offered more metabolic information.Results confirmed feasibility for tumor detection and showed superiority to single modality imaging. 展开更多
关键词 dual-modality imaging positron emission tomography fluorescence molecular tomography
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Fe3O4-based Nanoparticles for pH-responsive Dual-modality Imaging and Photothermal Therapy
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作者 Jiang Gu Li Fu Qianz Dong 《Advances in Modern Oncology Research》 2019年第4期14-18,共5页
The study designed a polyacrylic acid(PAA)modified Fe3O4@MnO2 nanoparticles(Fe3O4@MnO2@PAA)for T1/T2 dualmode imaging.In addition,this nano-drug has pH response and anti-tumor photothermal therapy.First,using Fe3O4 as... The study designed a polyacrylic acid(PAA)modified Fe3O4@MnO2 nanoparticles(Fe3O4@MnO2@PAA)for T1/T2 dualmode imaging.In addition,this nano-drug has pH response and anti-tumor photothermal therapy.First,using Fe3O4 as the core can significantly reduce the signal of Fe3O4@MnO2@PAA nanoparticles.MnO2 nanoshells can be decomposed into paramagnetic Mn2+under the acidic environment in the tumor,which enhanced the T1 signal.The pH-responsive T1/T2 dual-mode magnetic resonance imaging(MRI)contrast agent had good sensitivity and specificity,providing more comprehensive and detailed information for tumor diagnosis.In addition,Fe3O4@MnO2@PAA nanoparticles showed excellent absorption capacity in the near-infrared region(NIR),which could be used as a good photothermal conversion material to mediate photothermal treatment of tumors.Therefore,the pHresponsive dual-mode MRI nanoparticle-mediated photothermal therapy showed good application potential in tumor treatment and diagnosis. 展开更多
关键词 Magnetic resonance imaging Diagnostic and therapeutic agents dual-mode imaging Photothermal therapy
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Dual-Modality Integration Attention with Graph-Based Feature Extraction for Visual Question and Answering
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作者 Jing Lu Chunlei Wu +2 位作者 Leiquan Wang Ran Li Xiuxuan Shen 《Tsinghua Science and Technology》 2025年第5期2133-2145,共13页
Visual Question and Answering(VQA)has garnered significant attention as a domain that requires the synthesis of visual and textual information to produce accurate responses.While existing methods often rely on Convolu... Visual Question and Answering(VQA)has garnered significant attention as a domain that requires the synthesis of visual and textual information to produce accurate responses.While existing methods often rely on Convolutional Neural Networks(CNNs)for feature extraction and attention mechanisms for embedding learning,they frequently fail to capture the nuanced interactions between entities within images,leading to potential ambiguities in answer generation.In this paper,we introduce a novel network architecture,Dual-modality Integration Attention with Graph-based Feature Extraction(DIAGFE),which addresses these limitations by incorporating two key innovations:a Graph-based Feature Extraction(GFE)module that enhances the precision of visual semantics extraction,and a Dual-modality Integration Attention(DIA)mechanism that efficiently fuses visual and question features to guide the model towards more accurate answer generation.Our model is trained with a composite loss function to refine its predictive accuracy.Rigorous experiments on the VQA2.0 dataset demonstrate that DIAGFE outperforms existing methods,underscoring the effectiveness of our approach in advancing VQA research and its potential for cross-modal understanding. 展开更多
关键词 Visual Question and Answering(VQA) Graph-based Feature Extraction(GFE) dual-modality Integration Attention(DIA) composite loss
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Perfluorooctyl bromide nanoemulsions holding MnO_(2) nanoparticles with dual-modality imaging and glutathione depletion enhanced HIFU-eliciting tumor immunogenic cell death 被引量:2
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作者 Xinping Kuai Yuefei Zhu +8 位作者 Zheng Yuan Shengyu Wang Lin Lin Xiaodan Ye Yiping Lu Yu Luo Zhiqing Pang Daoying Geng Bo Yin 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第2期967-981,共15页
Tumor-targeted immunotherapy is a remarkable breakthrough,offering the inimitable advantage of specific tumoricidal effects with reduced immune-associated cytotoxicity.However,existing platforms suffer from low effica... Tumor-targeted immunotherapy is a remarkable breakthrough,offering the inimitable advantage of specific tumoricidal effects with reduced immune-associated cytotoxicity.However,existing platforms suffer from low efficacy,inability to induce strong immunogenic cell death(ICD),and restrained capacity of transforming immune-deserted tumors into immune-cultivated ones.Here,an innovative platform,perfluorooctyl bromide(PFOB)nanoemulsions holding MnO_(2) nanoparticles(MBP),was developed to orchestrate cancer immunotherapy,serving as a theranostic nanoagent for MRI/CT dual-modality imaging and advanced ICD.By simultaneously depleting the GSH and eliciting the ICD effect via highintensity focused ultrasound(HIFU)therapy,the MBP nanomedicine can regulate the tumor immune microenvironment by inducing maturation of dendritic cells(DCs)and facilitating the activation of CD8^(+)and CD4^(+)T cells.The synergistic GSH depletion and HIFU ablation also amplify the inhibition of tumor growth and lung metastasis.Together,these findings inaugurate a new strategy of tumor-targeted immunotherapy,realizing a novel therapeutics paradigm with great clinical significance. 展开更多
关键词 Immunogenic cell death NANOEMULSIONS Manganese dioxide nanoparticles Glutathione depletion dual-modality imaging High-intensity focused ultrasound Tumor microenvironment
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Novel multifunctional theranostic nanoagents based on Ho^(3+) for CT/MRI dual-modality imaging-guided photothermal therapy 被引量:2
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作者 Dongzhi Xue Yang Liu +10 位作者 Longhai Jin Yinghui Wang Fengzhi Cui Jianhua Liu Xiaoqing Li Songtao Zhang Ying Zhao Na Yin Rui Niu Daguang Wang Hongjie Zhang 《Science China Chemistry》 SCIE EI CAS CSCD 2021年第4期558-564,共7页
Because of the intrinsic defects of traditional treatment of cancer,it is quite needed to construct novel theranostic nanoagents that can not only improve the accuracy of imaging diagnosis but also achieve highly effi... Because of the intrinsic defects of traditional treatment of cancer,it is quite needed to construct novel theranostic nanoagents that can not only improve the accuracy of imaging diagnosis but also achieve highly efficient therapy of cancer.Herein,we fabricated polydopamine-functionalized ammonium holmium fluoride nanocomposites(AHF@PDA)for dual-modality bioimaging(magnetic resonance imaging(MRI)and computed tomography(CT))owing to the high X-ray attenuation feature and magnetic property of Ho^(3+).Moreover,PDA shell endows AHF@PDA with excellent photothermal conversion performances and robust biocompatibility,leading to good treatment effect in vitro and in vivo.All above positive results certify that AHF@PDA have good potential as theranostic agents for clinical application in the future. 展开更多
关键词 THERANOSTICS HOLMIUM dual-modality imaging photothermal therapy
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A dual-modality hydrogen sulfide-specific probe integrating chemiluminescence with NIR fluorescence for targeted cancer imaging
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作者 Xuemei Dong Lixin Sun +7 位作者 Ziwen Zhang Tianli Zhu Jie Sun Jinzhu Gao Chengjun Dong Rongchen Wang Xianfeng Gu Chunchang Zhao 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第6期1869-1876,共8页
Taking apart in numerous physiological and pathological activities,hydrogen sulfide(H_(2)S)has been selected as an excellent target spot for the early diagnosis of cancer.So far,there are many mature probes that apply... Taking apart in numerous physiological and pathological activities,hydrogen sulfide(H_(2)S)has been selected as an excellent target spot for the early diagnosis of cancer.So far,there are many mature probes that apply single optical imaging to monitor endogenous H_(2)S.Nevertheless,a single modality is not an ideal method to afford accurate diagnostic information in comprehensive biological organisms.Herein,we developed a dual-modal imaging probe BWS.This designed probe showed a specific response to H_(2)S with both chemiluminescence and NIR fluorescence light-up.The concurrence of fluorescence and chemiluminescence signal provided“double insurances”for highly accurate monitoring of H_(2)S.Satisfactorily,this dual-modal imaging probe performed precise visualization of endogenous H_(2)S in living cells and in vivo.We envisaged that this chemiluminescence/fluorescence real-time dual-modality strategy for H_(2)S detection will expand and optimize the multimodal imaging methods for efficient diagnosis and treatment of cancer. 展开更多
关键词 CHEMILUMINESCENCE FLUORESCENCE BODIPY dual-modal imaging H_(2)S
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A novel PEC-EC dual-mode biosensing platform for dual target detection of miRNA-133a and cTnI
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作者 Hejie Zheng Zhili Wang +3 位作者 Guizhen Luo Cuicui Du Xiaohua Zhang Jinhua Chen 《Chinese Chemical Letters》 2025年第4期588-592,共5页
Micro RNA-133a(mi RNA-133a) and cardiac troponin I(c Tn I) are different-type crucial biomarkers of acute myocardial infarction(AMI), whose levels are great significance for AMI diagnosis and treatment. Herein,a novel... Micro RNA-133a(mi RNA-133a) and cardiac troponin I(c Tn I) are different-type crucial biomarkers of acute myocardial infarction(AMI), whose levels are great significance for AMI diagnosis and treatment. Herein,a novel photoelectrochemical-electrochemical(PEC-EC) dual-mode biosensing platform for dual-target assays of mi RNA-133a and c Tn I was developed. In which, a PEC-EC dual-mode sensing platform for mi RNA-133a was constructed based on the changes of the photocurrent inhibition effect and the electrochemical signal of Fc on the Fc-hairpin DNA probe(Fc-HP)/Zn Cd S-quantum dots(QDs)/ITO electrode. Furthermore, under magnetic separation and the specific interaction between c Tn I and its aptamer, the N-doped porous carbon-Zn O polyhedra(NPC-Zn O)-hemin-capture DNA probe hybrid(NH-CP) was obtained and introduced to the Fc-HP/Zn Cd S-QDs/ITO electrode via hybridization between NH-CP and Fc-HP. The hemin molecules encapsulated in NH-CP could effectively induce the photocurrent-polarity-switching of the FcHP/Zn Cd S-QDs/ITO electrode and generate a new electrochemical signal originating from hemin. Thus,c Tn I was assayed sensitively and selectively by the PEC-EC dual-mode biosensing platform. Here, Fc and hemin not only serve as the electrochemical indicators, but also respectively inhibit the photocurrent and switch the photocurrent polarity of Zn Cd S-QDs. Furthermore, the proposed biosensing platform could be easily expanded to the detection of other multiplex-type biomarkers via the change of the sequences of the related DNA probes, implying its significant potential in clinical diagnosis and biological analysis. 展开更多
关键词 Photoelectrochemical assay Electrochemical assay dual-modE Dual-target miRNA-133a CTNI
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A Flexible Dual-Mode Photodetector for Human-Machine Collaborative IR Imaging
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作者 Huajing Fang Xinxing Xie +5 位作者 Kai Jing Shaojie Liu Ainong Chen Daixuan Wu Liyan Zhang He Tian 《Nano-Micro Letters》 2025年第10期63-75,共13页
Photothermoelectric(PTE)photodetectors with selfpowered and uncooled advantages have attracted much interest due to the wide application prospects in the military and civilian fields.However,traditional PTE photodetec... Photothermoelectric(PTE)photodetectors with selfpowered and uncooled advantages have attracted much interest due to the wide application prospects in the military and civilian fields.However,traditional PTE photodetectors lack of mechanical flexibility and cannot operate independently without the test instrument.Herein,we present a flexible PTE photodetector capable of dual-mode output,combining electrical and optical signal generation for enhanced functionality.Using solution processing,high-quality MXene thin films are assembled on asymmetric electrodes as the photosensitive layer.The geometrically asymmetric electrode design significantly enhances the responsivity,achieving 0.33 m A W^(-1)under infrared illumination,twice that of the symmetrical configuration.This improvement stems from optimized photothermal conversion and an expanded temperature gradient.The PTE device maintains stable performance after 300 bending cycles,demonstrating excellent flexibility.A new energy conversion pathway has been established by coupling the photothermal conversion of MXene with thermochromic composite materials,leading to a real-time visualization of invisible infrared radiation.Leveraging this functionality,we demonstrate the first human-machine collaborative infrared imaging system,wherein the dual-mode photodetector arrays synchronously generate human-readable pattern and machine-readable pattern.Our study not only provides a new solution for functional integration of flexible photodetectors,but also sets a new benchmark for human-machine collaborative optoelectronics. 展开更多
关键词 MXene dual-mode IR imaging Photothermoelectric THERMOCHROMIC Human-machine collaboration
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Research and application of thermosensitive Pickering emulsion with X-ray and ultrasound dual-modal imaging functions for intra-arterial embolization treatment
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作者 Ling Li Anran Guo +6 位作者 Haixia Sun Yanbing Zhao Qing Yao Ling Zhang Peng Shi Hongan Tian Min Zheng 《Journal of Pharmaceutical Analysis》 2025年第4期759-774,共16页
Transcatheter arterial embolization(TAE)is the mainstay for treating advanced hepatocellular carcinoma(HCC),and the performance of the embolization material is crucial in TAE.With the development of medical imaging an... Transcatheter arterial embolization(TAE)is the mainstay for treating advanced hepatocellular carcinoma(HCC),and the performance of the embolization material is crucial in TAE.With the development of medical imaging and the birth of“X-ray-free”technologies,we designed a new dual-mode imaging material of dimethoxy tetraphenyl ethylene(DMTPE)via emulsification by mixing poly(N-isopropylacrylamide-co-acrylic acid)(PNA)with lipiodol and fluorocarbons,which was evaluated for temperature sensitivity,stability,and dual-mode visualization in vitro.Additionally,blood vessel casting embolization and renal artery imaging were assessed in healthy rabbits.In a rabbit model with a VX2 tumor,the effectiveness of TAE for treating HCC was examined,with an emphasis on evaluating long-term outcomes of embolization and its effects on tumor growth,necrosis,and proliferation through imaging techniques.In vitro experiments confirmed that the temperature-sensitive dual-oil-phase Pickering emulsion had good flow,stable contrast,and embolism when the oil-to-oil ratio and water-to-oil ratio were both 7:3(v/v)and stabilized with 8%PNA.Similarly,in vivo,arterial embolization confirmed the excellent properties of DMTPE prepared at the abovementioned ratios.It was observed that DMTPE not only has an antitumor effect but can also achieve dual imaging using X-rays and ultrasound,making it a promising excellent vascular embolization material for TAE in tumor treatment. 展开更多
关键词 dual-modal imaging Temperature sensitivity Pickering emulsion Transcatheter arterial embolization
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Experimental study of pulsed injection on combustion mode transition in a dual-mode supersonic combustor
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作者 Guangming DU Changchun YAN +3 位作者 Ye TIAN Fuyu ZHONG Wei RAN Jialing LE 《Chinese Journal of Aeronautics》 2025年第9期26-42,共17页
This paper describes an experimental study investigating the effects of sinusoidal pulsed injection on the combustion mode transition in a dual-mode supersonic combustor.The results are obtained under inflow condition... This paper describes an experimental study investigating the effects of sinusoidal pulsed injection on the combustion mode transition in a dual-mode supersonic combustor.The results are obtained under inflow conditions of 2.9 MPa stagnation pressure,1900 K stagnation temperature,and Mach number of 3.0.It has been observed that,at the same equivalence ratio,the combustion mode and flow field structure undergo irreversible changes from a weak combustion state to a strong combustion state at a specific pulsed jet frequency compared to steady jet.For steady jet,the combustion mode is dual-mode.As the frequency of the unsteady jet changes,the combustion mode also changes:it becomes a transition mode at frequencies of 171 Hz and 260 Hz,and a ramjet mode at 216 Hz.Combustion instability under steady jet manifests as a transition in flame stabilization mode.In contrast,under pulsed jet,combustion instability appears either as a transition in flame stabilization mode or as flame blow-off and flashback.The flow field oscillation frequency in the non-reacting flow is 171 Hz,which may resonate with the 171 Hz pulsed jet frequency,making the combustion oscillations most pronounced at this frequency.When the jet frequency is increased to 216 Hz,the combustion intensity significantly increases,and the combustion mode transfers to the ramjet mode.However,further increasing the frequency to 260 Hz results in a decrease in combustion intensity,returning to the transition mode.The frequency of the flow field oscillations varies with the coupling of the pulsed injection frequency,shock wave,and flame,and if the system reaches an unstable state,that is,pre-combustion shock train moves far upstream of the isolator during the pulsed jet period,strong combustion state can be achieved,and this process is irreversible. 展开更多
关键词 Combustion instability Combustion mode transition dual-mode supersonic combustor Flame stabilization Fuel pulsed injection Supersonic aircraft
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NOVEL MICROSTRIP DUAL-MODE BANDPASS FILTER WITH COUPLING ENHANCEMENT AND WIDEBAND SPURIOUS RESPONSE SUPPRESSION
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作者 张雷 洪伟 周健义 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期379-387,共9页
The microstrip dual-mode filter (DMF) with conventional coupling structure has some limitations in- eluding the port coupling strength limited by fabrication tolerance and the existence of serious second order spuri... The microstrip dual-mode filter (DMF) with conventional coupling structure has some limitations in- eluding the port coupling strength limited by fabrication tolerance and the existence of serious second order spuri- ous band. Therefore, a novel DMF with a offset-feed bended coupling structure and a stepped-impedance dual- mode resonator is proposed for coupling enhancement and spurious response suppression. Based on the analysis of the change of spur frequencies and the current distribution of spur resonant modes, all spurs near passband of the cascaded DMF can be fully suppressed by optimizing the structure parameters of parasite resonators, which bene- fits from the inherent well-controlled transmission zeros. Experimental results show that the proposed DMF ex- hibits lower insertion loss ,much sharper rate of cutoff and wider spur-free stop band compared with conventional DMF. This design is applicable for spur suppression in wideband communication. 展开更多
关键词 dual-mode bandpass filter coupling structure spur suppression stepped-impedance resonator trans- mission zero
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Design and analysis of dual-mode structure repetitive control based hybrid current regulation scheme for active power filters
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作者 邹志翔 王政 程明 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期407-413,共7页
An all-digital hybrid current regulation scheme for the single-phase shunt active power filter (APF) is presented. The proposed hybrid current control scheme integrates the deadbeat control and the dual-mode structu... An all-digital hybrid current regulation scheme for the single-phase shunt active power filter (APF) is presented. The proposed hybrid current control scheme integrates the deadbeat control and the dual-mode structure repetitive control (DMRC) so that it can offer superior steady-state performance and good transient features. Unlike the conventional schemes, the proposed scheme-based APF can compensate both the odd and the even order harmonics in grid. The detailed design criteria and the stability analysis of the proposed hybrid current controller are presented. Moreover, an improved structure which incorporates the proposed hybrid controller and the resonant controller for tracking specific order harmonics is given. The relationships between the resonant controller and different repetitive control schemes are discussed. Experimental results verify the effectiveness and advantages of the proposed hybrid control scheme. 展开更多
关键词 active power filter dual-mode structure repetitive control (DMRC) current control harmonic compensation resonant controller
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TARGET INFORMATION DIFFERENTIATING TECHNOLOGY IN INFRARED-RADAR DUAL-MODE GUIDANCE SYSTEM
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作者 杨俊鹏 祝小平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期245-249,共5页
An improved target tracking information differentiating system using the neural network to substitute for fuzzy rules is presented for the infrared-radar dual-mode guidance system. Since the neural network training ba... An improved target tracking information differentiating system using the neural network to substitute for fuzzy rules is presented for the infrared-radar dual-mode guidance system. Since the neural network training based on the expert knowledge database is conducted off-line, the benefits for developing real-time tracking capabilities can be obtained. The network outputs the confidence degree denoted by the weight value of target information in the data fusion center according to two input variables of the measurement noise covariance and the tracking filter covariance. Simulation results show that the improved system can differentiate the target tracking information from the seeker fast and accurately. 展开更多
关键词 dual-mode guidance system confidence degree information differentiating
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Green and Near-Infrared Dual-Mode Afterglow of Carbon Dots and Their Applications for Confidential Information Readout 被引量:12
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作者 Yuci Wang Kai Jiang +4 位作者 Jiaren Du Licheng Zheng Yike Li Zhongjun Li Hengwei Lin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第12期148-162,共15页
Near-infrared(NIR),particularly NIR-containing dual-/multimode afterglow,is very attractive in many fields of application,but it is still a great challenge to achieve such property of materials. Herein,we report a fac... Near-infrared(NIR),particularly NIR-containing dual-/multimode afterglow,is very attractive in many fields of application,but it is still a great challenge to achieve such property of materials. Herein,we report a facile method to prepare green and NIR dual-mode afterglow of carbon dots(CDs) through in situ embedding o-CDs(being prepared from o-phenylenediamine) into cyanuric acid(CA) matrix(named o-CDs@CA). Further studies reveal that the green and NIR afterglows of o-CDs@CA originate from thermal activated delayed fluorescence(TADF) and room temperature phosphorescence(RTP) of o-CDs,respectively. In addition,the formation of covalent bonds between o-CDs and CA,and the presence of multiple fixation and rigid e ects to the triplet states of o-CDs are confirmed to be critical for activating the observed dual-mode afterglow. Due to the shorter lifetime and insensitiveness to human vision of the NIR RTP of o-CDs@CA,it is completely covered by the green TADF during directly observing. The NIR RTP signal,however,can be readily captured if an optical filter(cut-o wavelength of 600 nm) being used. By utilizing these unique features,the applications of o-CDs@CA in anti-counterfeiting and information encryption have been demonstrated with great confidentiality. Finally,the as-developed method was confirmed to be applicable to many other kinds of CDs for achieving or enhancing their afterglow performances. 展开更多
关键词 Carbon dots dual-mode afterglow Room temperature phosphorescence Thermal activated delayed fluorescence Information security
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Preparation and characterization of NaYF_4:Er^(3+),Tm^(3+)@NaYF_4:Ce^(3+),Tb^(3+) microcrystals with dual-mode emissions at the single-particle level 被引量:6
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作者 Xianfu Jiao Weihao Ye +3 位作者 Qiying Huang Jie Luo Linliang Yu Xiaotang Liu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第7期697-704,I0001,共9页
Under hydrothermal environment,we synthesized lanthanide ions doped sodium yttrium fluoride(NaYF4:Er,Tm@NaYF4:Ce,Tb) luminescent microcrystals via an epitaxial growth technique.The structure and morphology of these mi... Under hydrothermal environment,we synthesized lanthanide ions doped sodium yttrium fluoride(NaYF4:Er,Tm@NaYF4:Ce,Tb) luminescent microcrystals via an epitaxial growth technique.The structure and morphology of these microcrystals were examined by SEM,TEM,EDS and XRD measurements.These particles show dual-mode emissions with red upconversion(UC) and green down conversion(DC) as single particles level.The mean length and diameter of these microparticles increase from 0.43 to2.26 μm and from 1.33 to 1.86 μm,respectively.Most interestingly,the photoluminescence properties of NaYF4:Er,Tm@NaYF4:Ce,Tb phosphor crystals are highly dependent on the crystallite size.The microcrystals fluoresce emit dual-mode emissions when they are solid or dispersed in solvents.Benefiting its intensive fluorescence and uniform morphology,these materials hold great potential for security and anti-counterfeiting applications. 展开更多
关键词 NaYF4 microcrystals dual-mode fluorescence materials Single-particles CORE-SHELL HYDROTHERMAL Rare earths
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Dual-mode Nonlinear MPC via Terminal Control Laws With Free-parameters 被引量:7
19
作者 Defeng He 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第3期526-533,共8页
The paper presents a new dual-mode nonlinear model predictive control(NMPC) scheme for continuous-time nonlinear systems subject to constraints on the state and control.The idea of control Lyapunov functions for nonli... The paper presents a new dual-mode nonlinear model predictive control(NMPC) scheme for continuous-time nonlinear systems subject to constraints on the state and control.The idea of control Lyapunov functions for nonlinear systems is used to compute the terminal regions and terminal control laws with some free-parameters in the dual-mode NMPC framework.The parameters of the terminal controller are selected offline to estimate the terminal region as large as possible;and the parameters are optimized online to gain optimality of the terminal controller with respect to given cost functions.Then a dual-mode NMPC algorithm with varying time-horizon is formulated for the constrained system.Recursive feasibility and closed-loop stability of this NMPC are established.The example of a spring-cart is used to demonstrate the advantages of the presented scheme by comparing to the dual-mode NMPC via the linear quadratic regulator(LQR) method. 展开更多
关键词 Constrained control dual-mode control model predictive control nonlinear control
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Thermal behavior of an isolator with mode transition inducing back-pressure of a dual-mode scramjet 被引量:4
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作者 Yang Qingchun Bao Wen +2 位作者 Chetehouna Khaled Zhang Silong Gascoin Nicolas 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第2期595-601,共7页
Combustion mode transition is a valuable and challenging research area in dual-mode scramjet engines.The thermal behavior of an isolator with mode transition inducing backpressure is investigated by direct-connect dua... Combustion mode transition is a valuable and challenging research area in dual-mode scramjet engines.The thermal behavior of an isolator with mode transition inducing backpressure is investigated by direct-connect dual-mode scramjet experiments and theoretical analysis.Combustion experiments are conducted under the incoming airflow conditions of total temperature1270 K and Mach 2.A small increment of the fuel equivalence ratio is scheduled to trigger mode transition.Correspondingly,the variation of the coolant flow rate is very small.Based on the measured wall pressures,the heat-transfer model can quantify the thermal state variation of the engine with active cooling.Compared with the combustor,mode transition has a greater effect on the isolator thermal behavior,and it significantly changes the isolator heat-flux and wall temperature.To further study the isolator thermal behavior from flight Mach 4 to Mach 7,a theoretical analysis is carried out.Around the critical point of combustion mode transition,sudden changes of the isolator flowfield and thermal state are discussed. 展开更多
关键词 Combustion mode dual-mode scramjet ISOLATOR Mode transition Thermal behavior
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