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A crosstalk-free dual-mode sweat sensing system for naked-eye sweat loss quantification via changes in structural reflectance 被引量:1
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作者 Bowen Zhong Hao Xu +3 位作者 Xiaokun Qin Lingchen Liu Hailong Wang Lili Wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期428-438,共11页
Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal m... Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal method for the fabrication of colorimetric microfluidics designed for sweat loss monitoring remains challenging.In this study,we propose a novel laserengraved surface roughening strategy for various flexible substrates.This process permits the construction of microchannels that show distinct structural reflectance changes before and after sweat filling.By leveraging these unique optical properties,we have developed a fully laser-engraved microfluidic device for the quantification of naked-eye sweat loss.This sweat loss sensor is capable of a volume resolution of 0.5µL and a total volume capacity of 11µL,and can be customized to meet different performance requirements.Moreover,we report the development of a crosstalk-free dual-mode sweat microfluidic system that integrates an Ag/AgCl chloride sensor and a matching wireless measurement flexible printed circuit board.This integrated system enables the real-time monitoring of colorimetric sweat loss signals and potential ion concentration signals without crosstalk.Finally,we demonstrate the potential practical use of this microfluidic sweat loss sensor and its integrated system for sports medicine via on-body studies. 展开更多
关键词 Sweat loss sensor Microfluidic design Structural reflectance dual-mode integration Crosstalk-free
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One stone two birds:electrochemical and colorimetric dual-mode biosensor based on copper peroxide/covalent organic framework nanocomposite for ultrasensentive norovirus detection
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作者 Guobao Ning Quanmei Duan +6 位作者 Huan Liang Huifang Liu Min Zhou Chunlan Chen Chong Zhang Hui Zhao Canpeng Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期920-931,共12页
Norovirus(NoV)is regarded as one of the most common causes of foodborne diarrhea in the world.It is urgent to identify the pathogenic microorganism of the diarrhea in short time.In this work,we developed an electroche... Norovirus(NoV)is regarded as one of the most common causes of foodborne diarrhea in the world.It is urgent to identify the pathogenic microorganism of the diarrhea in short time.In this work,we developed an electrochemical and colorimetric dual-mode detection for NoV based on the excellent dual catalytic properties of copper peroxide/COF-NH_(2)nanocomposite(CuO_(2)@COF-NH_(2)).For the colorimetric detection,NoV can be directly detected by the naked eye based on CuO_(2)@COF-NH_(2)as a laccase-like nonazyme using“peptide-NoV-antibody”recognition mode.The colorimetric assay displayed a wide and quality linear detection range from 1 copy/mL to 5000 copies/mL of NoV with a low limit of detection(LOD)of 0.125 copy/mL.For the electrochemical detection of NoV,CuO_(2)@COF-NH_(2)showed an oxidation peak of copper ion from Cu^(+)to Cu^(2+)using“peptide-NoV-antibody”recognition mode.The electrochemical assay showed a linear detection range was 1-5000 copies/mL with a LOD of 0.152 copy/mL.It's worthy to note that this assay does not need other electrical signal molecule,which provide the stable and sensitive electrochemial detection for NoV.The electrochemical and colorimetric dual-mode detection was used to detect NoV in foods and faceal samples,which has the potential for improving food safety and diagnosing of NoV-infected diarrhea. 展开更多
关键词 NOROVIRUS Specific peptides Electrochemical and colorimetric assay dual-mode Copper peroxide/covalent organic framework
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CF-BFT:A Dual-Mode Byzantine Fault-Tolerant Protocol Based on Node Authentication
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作者 Zhiruo Zhang Feng Wang +2 位作者 Yang Liu Yang Lu Xinlei Liu 《Computers, Materials & Continua》 SCIE EI 2023年第9期3113-3129,共17页
The consensus protocol is one of the core technologies in blockchain,which plays a crucial role in ensuring the block generation rate,consistency,and safety of the blockchain system.Blockchain systems mainly adopt the... The consensus protocol is one of the core technologies in blockchain,which plays a crucial role in ensuring the block generation rate,consistency,and safety of the blockchain system.Blockchain systems mainly adopt the Byzantine Fault Tolerance(BFT)protocol,which often suffers fromslow consensus speed and high communication consumption to prevent Byzantine nodes from disrupting the consensus.In this paper,this paper proposes a new dual-mode consensus protocol based on node identity authentication.It divides the consensus process into two subprotocols:Check_BFT and Fast_BFT.In Check_BFT,the replicas authenticate the primary’s identity by monitoring its behaviors.First,assume that the systemis in a pessimistic environment,Check_BFT protocol detects whether the current environment is safe and whether the primary is an honest node;Enter the fast consensus stage after confirming the environmental safety,and implement Fast_BFT protocol.It is assumed that there are 3f+1 nodes in total.If more than 2f+1 nodes identify that the primary is honest,it will enter the Fast_BFT process.In Fast_BFT,the primary is allowed to handle transactions alone,and the replicas can only receive the messages sent by the primary.The experimental results show that the CF-BFT protocol significantly reduces the communication overhead and improves the throughput and scalability of the consensus protocol.Compared with the SAZyzz protocol,the throughput is increased by 3 times in the best case and 60%in the worst case. 展开更多
关键词 Blockchain consensus protocol dual-mode Byzantine fault tolerance distributed system
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On Dual-Mode Driving Control Method for a Novel Unmanned Tractor With High Safety and Reliability
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作者 Wei Lu Jiacheng Li +2 位作者 Huanhuan Qin Lei Shu Aiguo Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期254-271,共18页
Due to the non-standardization and complexity of the farmland environment,it is always a huge challenge for tractors to achieve fully autonomy(work at Self-driving mode)all the time in agricultural industry.Whereas,wh... Due to the non-standardization and complexity of the farmland environment,it is always a huge challenge for tractors to achieve fully autonomy(work at Self-driving mode)all the time in agricultural industry.Whereas,when tractors work in the Tele-driving(or Remote driving)mode,the operators are prone to fatigue because they need to concentrate for long periods of time.In response to these,a dual-mode control strategy was proposed to integrate the advantages of both approaches,i.e.,by combing Self-driving at most of the time with Tele-driving under special(complex and hazardous)conditions through switching control method.First,the state switcher was proposed,which is used for smooth switching the driving modes according to different working states of a tractor.Then,the state switching control law and the corresponding subsystem tracking controllers were designed.Finally,the effectiveness and superiority of the dualmode control method were evaluated via actual experimental testing of a tractor whose results show that the proposed control method can switch smoothly,stably,and efficiently between the two driving modes automatically.The average control accuracy has been improved by 20%and 15%respectively,compared to the conventional Tele-driving control and Self-driving control with low-precision navigation.In conclusion,the proposed dualmode control method can not only satisfy the operation in the complex and changeable farmland environment,but also free drivers from high-intensity and fatiguing work.This provides a perfect application solution and theoretical support for the intelligentization of unmanned farm agricultural machinery with high safety and reliability. 展开更多
关键词 dual-mode control safety and reliability self-driving(SD) tele-driving(TD) unmanned tractor
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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
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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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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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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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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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Analysis Method and Principle of Dual-mode Electro-mechanical Variable Transmission Program 被引量:6
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作者 LI Hongcai YAN Qingdong +1 位作者 XIANG Changle WANG Weida 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期524-529,共6页
Automotive industry,as an important pillar of the national economy,has been rapidly developing in recent years.But proplems such as energy comsumption and environmental pollution are posed at the same time.Electro-mec... Automotive industry,as an important pillar of the national economy,has been rapidly developing in recent years.But proplems such as energy comsumption and environmental pollution are posed at the same time.Electro-mechanical variable transmission system is considered one of avilable workarounds.It is brought forward a kind of design methods of dual-mode electro-mechanical variable transmission system rotational speed characteristics and dual-mode drive diagrams.With the motor operating behavior of running in four quadrants and the speed characteristics of the simple internal and external meshing single planetary gear train,four kinds of dual-mode electro-mechanical transmission system scheme are designed.And the velocity,torque and power characteristics of one of the programs are analyzed.The magnitude of the electric split-flow power is an important factor which influences the system performance,so in the parameters matching design,it needs to reduce the power needs under the first mode of the motor.The motor,output rotational speed range and the position of the mode switching point have relationships with the characteristics design of the planetary gear set.The analysis method is to provide a reference for hybrid vehicles' design.As the involved rotational speed and torque relationships are the natural contact of every part of transmission system,a theory basis of system program and performance analysis is provided. 展开更多
关键词 electro-mechanical variable transmission dual-mode rotational speed characteristics
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Green and Near-Infrared Dual-Mode Afterglow of Carbon Dots and Their Applications for Confidential Information Readout 被引量:9
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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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Dual-mode Nonlinear MPC via Terminal Control Laws With Free-parameters 被引量:7
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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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Preparation of NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu3+double-jacket microtubes for dual-mode fluorescent anti-counterfeiting 被引量:3
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作者 Yin CHEN Shao-wen XIE +4 位作者 Chao TONG Hai-hu TAN Li-jian XU Na LI Jian-xiong XU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3333-3346,共14页
Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+she... Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing. 展开更多
关键词 lanthanide-doped fluoride core-shell structure dual-mode luminescence inkjet printing anti- counterfeiting
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Facile Approach to Synthesize Gold Nanorod@Polyacrylic Acid/Calcium Phosphate Yolk–Shell Nanoparticles for Dual-Mode Imaging and pH/NIR-Responsive Drug Delivery 被引量:4
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作者 Guilan Li Yidan Chen +5 位作者 Lingyu Zhang Manjie Zhang Shengnan Li Lu Li Tingting Wang Chungang Wang 《Nano-Micro Letters》 SCIE EI CAS 2018年第1期63-73,共11页
A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate(Au NR@-PAA/Ca P) yolk–shell nanoparticles(NPs) composed with a PAA/Ca P shell and an Au NR yolk is reported. The asobtained Au NR@PAA/Ca ... A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate(Au NR@-PAA/Ca P) yolk–shell nanoparticles(NPs) composed with a PAA/Ca P shell and an Au NR yolk is reported. The asobtained Au NR@PAA/Ca P yolk–shell NPs possess ultrahigh doxorubicin(DOX) loading capability(1 mg DOX/mg NPs), superior photothermal conversion property(26%)and p H/near-infrared(NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the Ca P shell at low p H values. When the DOX-loaded Au NR@PAA/Ca P yolk–shell NPs wereexposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the Au NRs. Furthermore,Au NR@PAA/Ca P yolk–shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications. 展开更多
关键词 Yolk–shell structure Calcium phosphate dual-mode imaging Photothermal therapy Drug delivery
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NOVEL COMPOSITE CVT SYSTEMS WITH DIVERGING AND DUAL-MODE CONVERGING POWER FLOW 被引量:2
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作者 Liu Shudao Huang Xiangdong +1 位作者 Zhao Kegang Luo Yutao College of Traffic & Communications,South China University of Technology,Guangzhou 510640, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期257-262,共6页
A new type of composite CVT(continuously variable transmission) systemsfeatured by power flow divergence and dual-mode convergence, capable of improving CVT's efficiencyand power capacity or making AMTs(automated ... A new type of composite CVT(continuously variable transmission) systemsfeatured by power flow divergence and dual-mode convergence, capable of improving CVT's efficiencyand power capacity or making AMTs(automated manual transmissions) become continuously variable, isstudied. With specific mechano-mechanical and electromechanical composite CVT systems as detailedexamples, its basic working principles are expatiated. General methods and key points in designingand realizing such systems are also analyzed and discussed. 展开更多
关键词 Composite CVT Planetary gear set dual-mode power convergence
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Magnetically-coated silica nanospheres for dual-mode imaging at low ultrasound frequency 被引量:1
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作者 Fernanda Chiriacò Giulia Soloperto +4 位作者 Antonio Greco Francesco Conversano Andrea Ragusa Luca Menichetti Sergio Casciaro 《World Journal of Radiology》 CAS 2013年第11期411-420,共10页
AIM: To experimentally investigate the acoustical behavior of different dual-mode nanosized contrast agents(NPCAs) for echographic medical imaging at low ultrasound(US) frequency. METHODS: We synthesized three differe... AIM: To experimentally investigate the acoustical behavior of different dual-mode nanosized contrast agents(NPCAs) for echographic medical imaging at low ultrasound(US) frequency. METHODS: We synthesized three different nanosized structures:(1) Pure silica nanospheres(SiNSs);(2) FePt-iron oxide(FePt-IO)-coated SiNSs; and(3) IOcoated SiNSs, employing three different diameter of SiNS-core(160, 330 and 660 nm). Tissue mimicking phantoms made of agarose gel solution containing 5 mg of different NPCAs in 2 mL-Eppendorf tubes, were insonified by a commercial echographic system at three different low US pulse values(2.5, 3.5 and 4.5 MHz). The raw radiofrequency signal, backscattered from each considered NPCA containing sample, has been processed in order to calculate the US average backscatter intensity and compare the acoustic behavior of the different NPCA types. RESULTS: The highest US contrast was exhibited by pure SiNSs; FePt-IO-coated SiNSs acoustical behavior followed a similar trend of pure SiNSs with a slight difference in terms of brightness values. The acoustic response of the examined NPCAs resulted function of both SiNS diameter and US frequency. Specifically, higher US frequencies determined higher value of the backscatter for a given SiNS diameter. Frequencydependent enhancement was marked for pure SiNSs and became less remarkable for FePt-IO-coated SiNSs, whereas IO-coated SiNSs resulted almost unaffected by such frequency variations. Pure and FePt-IO-coated SiNSs evidenced an image backscatter increasing with the diameter up to 330 nm. Conversely, among the types of NPCA tested, IO-coated SiNSs showed the lowest acoustical response for each synthesized diameter and employed US frequency, although a diameter-dependent raising trend was evidenced. CONCLUSION: The US characterization of magnetically covered SiNS shows that FePt-IO, rather than IO, was the best magnetic coating for realizing NPCAs suitable for dual mode imaging of deep organs, combining US and magnetic resonance imaging. 展开更多
关键词 ULTRASOUND Magnetic resonance NANOCOMPOSITE dual-mode IMAGING CONTRAST agent Diagnostic IMAGING
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A GPS/BDS dual-mode positioning algorithm for a train based on CIPSO_EKF 被引量:2
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作者 LUO Miao DANG Jianwu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期12-20,共9页
When using global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode navigation system to locate a train,Kalman filter that is used to calculate train position has to be adjusted according to the feature... When using global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode navigation system to locate a train,Kalman filter that is used to calculate train position has to be adjusted according to the features of the dual-mode observation.Due to multipath effect,positioning accuracy of present Kalman filter algorithm is really low.To solve this problem,a chaotic immune-vaccine particle swarm optimization_extended Kalman filter(CIPSO_EKF)algorithm is proposed to improve the output accuracy of the Kalman filter.By chaotic mapping and immunization,the particle swarm algorithm is first optimized,and then the optimized particle swarm algorithm is used to optimize the observation error covariance matrix.The optimal parameters are provided to the EKF,which can effectively reduce the impact of the observation value oscillation caused by multipath effect on positioning accuracy.At the same time,the train positioning results of EKF and CIPSO_EKF algorithms are compared.The eastward position errors and velocity errors show that CIPSO_EKF algorithm has faster convergence speed and higher real-time performance,which can effectively suppress interference and improve positioning accuracy. 展开更多
关键词 global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode positioning chaotic immune-vaccine particle swarm optimization(CIPSO) extended Kalman filter(EKF) positioning accuracy
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Pressure performance improvement by dual-mode control in digital pump/motor
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作者 LI Chun-shuang WANG Xin +2 位作者 QI Hai-bo LIU Xin-yu LIU Xin-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2628-2642,共15页
Due to the advantages of low cost,fast response and pollution resistance,digital hydraulic pump/motor can replace conventional variable hydraulic pump/motor in many application fields.However,digital hydraulic compone... Due to the advantages of low cost,fast response and pollution resistance,digital hydraulic pump/motor can replace conventional variable hydraulic pump/motor in many application fields.However,digital hydraulic components produce large hydraulic impact at variable moments,which will shorten the service life of mechanical components.Through the simulation analysis of the variable process of digital pump/motor,it is found that the discontinuous flow caused by displacement step changes is the fundamental cause of hydraulic impact.The data analysis results of experimental tests are in good agreement with the simulation analysis results.In view of hydraulic secondary components,a variable control method based on dual-mode operating characteristics is proposed.The TOPSIS algorithm is used to give comprehensive evaluation of the displacement control results after this method.The results show that the control quality of digital pump/motor after adopting the control method has been effectively improved,with an average improvement of about 40%. 展开更多
关键词 digital hydraulic dual-mode operating characteristics AMESim simulation TOPSIS algorithm
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Engine performance analysis and optimization of a dual-mode scramjet with varied inlet conditions
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作者 Lu Tian Li-Hong Chen +2 位作者 Qiang Chen Feng-Quan Zhong Xin-Yu Chang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期75-82,共8页
A dual-mode scramjet can operate in a wide range of flight conditions. Higher thrust can be generated by adopting suitable combustion modes. Based on the net thrust, an analysis and preliminary optimal design of a ker... A dual-mode scramjet can operate in a wide range of flight conditions. Higher thrust can be generated by adopting suitable combustion modes. Based on the net thrust, an analysis and preliminary optimal design of a kerosene-fueled parameterized dual-mode scramjet at a cru- cial flight Mach number of 6 were investigated by using a modified quasi-one-dimensional method and simulated annealing strategy. Engine structure and heat release distrib- utions, affecting the engine thrust, were chosen as analytical parameters for varied inlet conditions (isolator entrance Mach number: 1.5-3.5). Results show that different opti- mal heat release distributions and structural conditions can be obtained at five different inlet conditions. The highest net thrust of the parameterized dual-mode engine can be achieved by a subsonic combustion mode at an isolator entrance Mach number of 2.5. Additionally, the effects of heat release and scramjet structure on net thrust have been discussed. The present results and the developed analytical method can provide guidance for the design and optimization of high-performance dual-mode scramjets. 展开更多
关键词 dual-mode scramjet Engine performance THRUST OPTIMIZATION Heat release distribution Simulatedannealing algorithm
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A single dual-mode gas sensor for early safety warning of Li-ion batteries:Micro-scale Li dendrite and electrolyte leakage
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作者 Wenjun Yan Zhishen Jin +4 位作者 Zhengyang Lin Shiyu Zhou Yonghai Du Yulong Chen Houpan Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期291-296,共6页
Li dendrites and electrolyte leakage are common causes of Li-ion battery failure.H_(2),generated by Li dendrites,and electrolyte vapors have been regarded as gas markers of the early safety warning of Li-ion batteries... Li dendrites and electrolyte leakage are common causes of Li-ion battery failure.H_(2),generated by Li dendrites,and electrolyte vapors have been regarded as gas markers of the early safety warning of Li-ion batteries.SnO_(2)-based gas sensors,widely used for a variety of applications,are promising for the early safety detection of Li-ion batteries,which are necessary and urgently required for the development of Li-ion battery systems.However,the traditional SnO_(2)sensor,with a single signal,cannot demonstrate intelligent multi-gas recognition.Here,a single dual-mode(direct and alternating current modes)SnO_(2)sensor demonstrates clear discrimination of electrolyte vapors and H_(2),released in different states of Li-ion batteries,together with principal component analysis(PCA)analysis.This work provides insight into the intelligent technology of single gas sensors. 展开更多
关键词 gas sensors single dual-mode multivariable sensors Li-batteries early safety warning
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New Planar Dual-Mode Filters without Coupling Gaps
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作者 王学东 姬五胜 李英 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期333-336,共4页
A class of new planar dual-mode filters without coupling gaps is proposed. The proposed structures use a single patch wiuhout coupling gaps. Attenuation poles can be implemented on either side of the passband by chang... A class of new planar dual-mode filters without coupling gaps is proposed. The proposed structures use a single patch wiuhout coupling gaps. Attenuation poles can be implemented on either side of the passband by changing the locations of two feed lines. By cutting two corners in the patch, two attenuation poles on both sides of passband are implemented. A novel dual-mode elliptic-function bandpass filter structure without coupling gaps is also proposed. These new filters can provide a low insertion loss and reduce uncertainty in fabrication owing to the absence of coupling gaps. 展开更多
关键词 bandpass filters attenuation pole dual-mode filters patch resonators.
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