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Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet
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作者 Haojie Jia Yanwei Liu +6 位作者 Weiqin Zuo Hongkai Han Ping Chang Mohammad Waqar Ali Asad Guozhong Hu Jian Miao Hani SMitri 《International Journal of Mining Science and Technology》 2025年第2期175-189,共15页
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug... Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. 展开更多
关键词 MULTI-FREQUENCY modulation SELF-PRimING Submerged waterjet CAVITATION
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Comprehensive pan-cancer analysis of NCOA family members:insights into tumorigenesis,genomic alterations,and immune modulation
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作者 Xin Li Wan-Rong Li Hao Jin 《Cancer Advances》 2025年第3期1-9,共9页
Background:The nuclear receptor coactivator(NCOA)family,including NCOA1,NCOA2,and NCOA3,is critical in regulating gene expression through interactions with nuclear receptors and other transcription factors.These coact... Background:The nuclear receptor coactivator(NCOA)family,including NCOA1,NCOA2,and NCOA3,is critical in regulating gene expression through interactions with nuclear receptors and other transcription factors.These coactivators are implicated in various cancers,but their comprehensive roles across different cancer types remain poorly understood.Methods:We performed a pan-cancer bioinformatics analysis using data from The Cancer Genome Atlas and the Genotype-Tissue Expression project.We assessed the differential expression,copy number variations,mutations,methylation status,tumor mutation burden,microsatellite instability,and immune cell infiltration associated with NCOA family members across various cancers.Differential expression analysis was conducted using the DESeq2 package.Methylation data were analyzed using the ChAMP package,and immune cell infiltration was estimated using the CIBERSORT algorithm.Results:NCOA1 and NCOA2 were predominantly downregulated in multiple cancers,suggesting potential tumor suppressor roles,whereas NCOA3 was largely upregulated,indicating a consistent oncogenic function.These expression patterns significantly correlated with patient prognosis.Frequent copy number variations,particularly gains,and high mutation rates were observed in NCOA2.NCOA3 demonstrated consistent hypomethylation in tumors,which was associated with increased gene expression.Significant correlations were found between NCOA expression and tumor mutation burden,microsatellite instability,and immune cell infiltration,indicating their involvement in genomic instability and immune modulation.Conclusion:This comprehensive analysis reveals significant alterations in the expression,genomic,and epigenetic profiles of NCOA family members across various cancers.The findings highlight the multifaceted roles of NCOA1,NCOA2,and NCOA3 in tumorigenesis and their potential as biomarkers and therapeutic targets.Future research should focus on elucidating the mechanisms underlying the associations between NCOA expression,genomic alterations,and immune modulation to develop targeted cancer therapies. 展开更多
关键词 NCOA family immune modulation bioinformatics analysis cancer biomarkers
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Direct measurement and optimization of the polarization-dependent modulation depth in super-resolution structured illumination microscopy
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作者 Linbo Wang Simin Li +4 位作者 Xiaohu Chen Xin Jin Jie Zhang Hui Li Gang Wen 《Journal of Innovative Optical Health Sciences》 2025年第4期121-131,共11页
Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical... Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical components can depolarize the laser beams hence degenerating the modulation depth.Here,we first presented a direct measurement method designed to estimate the modulation depth more precisely by shifting illumination patterns with equal phase steps.This measurement method greatly reduces the dependence of modulation depths on the samples,and then developed a polarization optimization method to achieve high modulation depth at all orientations by actively and quantitatively compensating for the additional phase difference using a combination of waveplate and a liquid crystal variable retarder(LCVR).Experimental results demonstrate that our method can achieve illumination patterns with modulation depth higher than 0.94 at three orientations with only one LCVR voltage,which enables isotropic resolution improvement. 展开更多
关键词 Structured illumination microscopy DEPOLARIZATION modulation depth phase compensation
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Optimization strategies for operational parameters of Rydberg atom-based amplitude modulation receiver
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作者 Yuhao Wu Dongping Xiao +1 位作者 Huaiqing Zhang Sheng Yan 《Chinese Physics B》 2025年第1期280-287,共8页
The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches... The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches between the parameters of the received amplitude modulation(AM) signals and the system's linear workspace and demodulation operating points can cause severe distortion in the demodulated signals. To address this, the article proposes a method for determining the operational parameters based on the mean square error(MSE) and total harmonic distortion(THD) assessments and presents strategies for optimizing the system's operational parameters focusing on linear response characteristics(LRC) and linear dynamic range(LDR). Specifically, we employ a method that minimizes the MSE to define the system's linear workspace, thereby ensuring the system has a good LRC while maximizing the LDR. To ensure that the signal always operates within the linear workspace, an appropriate carrier amplitude is set as the demodulation operating point. By calculating the THD at different operating points, the LRC performance within different regions of the linear workspace is evaluated, and corresponding optimization strategies based on the range of signal strengths are proposed. Moreover, to more accurately restore the baseband signal, we establish a mapping relationship between the carrier Rabi frequency and the transmitted power of the probe light, and optimize the slope of the linear demodulation function to reduce the MSE to less than 0.8×10^(-4). Finally, based on these methods for determining the operational parameters, we explore the effects of different laser Rabi frequencies on the system performance, and provide optimization recommendations. This research provides robust support for the design of high-performance Rydberg atom-based AM receivers. 展开更多
关键词 Rydberg atom-based receiver amplitude modulation(AM) operating parameters OPTimIZATION
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Sustainable Carbon-Based Catalyst Materials Derived From Lignocellulosic Biomass for Energy Storage and Conversion:Atomic Modulation and Properties Improvement
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作者 Wei Li Ying Xu +4 位作者 Guanhua Wang Ting Xu Kui Wang Shangru Zhai Chuanling Si 《Carbon Energy》 2025年第5期55-100,共46页
Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic ap... Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently.Due to the catalytic deficiency of neutral carbon atoms,the usage of single lignocellulosic-based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability.However,atomic-level modulation of lignocellulose-based carbon materials can optimize the electronic structures,charge separation,transfer processes,and so forth,which results in substantially enhanced electrocatalytic performance of carbon-based catalysts.This paper reviews the recent advances in the rational design of lignocellulosic-based carbon materials as electrocatalysts from an atomic-level perspective,such as self/external heteroatom doping and metal modification.Then,through systematic discussion of the design principles and reaction mechanisms of the catalysts,the applications of the prepared lignocellulosic-based catalysts in rechargeable batteries and electrocatalysis are reviewed.Finally,the challenges in improving the catalytic performance of lignocellulosic-based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed.This review contributes to the synthesis strategy of lignocellulose-based carbon electrocatalysts via atomic-level modulation,which in turn promotes the lignocellulose valorization for energy storage and conversion. 展开更多
关键词 atomic modulation carbon materials ELECTROCATALYSIS lignocellulosic biomass rechargeable batteries
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Large-angle stimulated Raman scattering induced by transverse density modulation
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作者 Z.M.Huang Qing Wang +12 位作者 R.J.Cheng X.X.Li S.Y.Lv D.J.Liu Z.Y.Xu S.T.Zhang Z.J.Chen Qiang Wang C.Z.Xiao Z.J.Liu L.H.Cao C.Y.Zheng X.T.He 《Matter and Radiation at Extremes》 2025年第5期64-72,共9页
Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show t... Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show that the scattering angle of SRS in a longitudinally inhomogeneous plasma can be significantly affected by transverse density modulation.Under transverse density modulation conditions,the laser focuses into underdense regions,owing to the transversely modulated refractive index.The angle of LA-SRS,neither a purely 90° angle side scattering nor purely backscattering,is almost consistent with the specific angle at which the density inhomogeneity vanishes.In modulated plasmas,the nonuniform distribution of laser intensity shifts the regions of scattering and gain compared with those in uniform plasmas,ultimately affecting the laser transmission.SRS is suppressed in weakly modulated regimes,whereas it is enhanced under strong modulation conditions,and a theoretical criterion distinguishing between strong and weak modulation is established. 展开更多
关键词 longitudinally inhomogeneous plasma transverse density modulation numerical simulationsthe transversely modulated refractive indexthe large angle stimulated Raman scattering three wave coupled model transverse density modulationunder
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Research onπ/4QPSK Modulation Communication Transmission System and FPGA Implementation
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作者 Yuhui Chu Yunjie Yuan +2 位作者 Xiaolei Cai Yanyan Wang Peijie Yin 《Journal of Electronic Research and Application》 2025年第2期12-17,共6页
This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation... This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation scheme for a modulation communication transmission system,integrating RS channel coding,framing,frequency conversion,and other modules.This design is based on practical research and development requirements.The Xilinx Spartan6 chip board was used for board-level verification.Theπ/4QPSK modulated signal was transmitted via D/A conversion and radio frequency,with the transmitted waveform was looped back for reception.After A/D processing,the correctness of the designed modulation transmission scheme was verified. 展开更多
关键词 π/4QPSK modulation FPGA
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Dynamic hybrid visual-thermal multimodal perception neuromorphic devices based on defect modulation of electrospun nanofibers
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作者 Shengkai Wen Yanan Liu +3 位作者 Yi Li Liang Xie Jun Li Jianhua Zhang 《International Journal of Extreme Manufacturing》 2025年第2期749-761,共13页
Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mo... Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mode of external information acquisition in living organisms,has garnered substantial scholarly interest.Notwithstanding numerous studies simulating the retina through optical synapses,their applications remain circumscribed to single-mode perception.Moreover,the pivotal role of temperature,a fundamental regulator of biological activities,has regrettably been relegated to the periphery.To address these limitations,we proffer a neuromorphic device endowed with multimodal perception,grounded in the principles of light-modulated semiconductors.This device seamlessly accomplishes dynamic hybrid visual and thermal multimodal perception,featuring temperature-dependent paired pulse facilitation properties and adaptive storage.Crucially,our meticulous examination of transfer curves,capacitance–voltage(C–V)tests,and noise measurements provides insights into interface and bulk defects,elucidating the physical mechanisms underlying adaptive storage and other functionalities.Additionally,the device demonstrates a variety of synaptic functionalities,including filtering properties,Ebbinghaus curves,and memory applications in image recognition.Surprisingly,the digital recognition rate achieves a remarkable value of 98.8%. 展开更多
关键词 neuromorphic devices electrospinning defect modulation dynamic hybrid multimodal perception adaptive storage
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Sequential-gated transformable nanoprodrug potentiates antitumor immunity through TME modulation and STING activation
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作者 Yongjuan Li Rongrong Zhu +5 位作者 Yichen Guo Yayun Wang Rong Ma Kunru Ma Yongxing Zhao Weijing Yang 《Chinese Chemical Letters》 2025年第9期458-465,共8页
Nanomaterials that can sequentially respond to internal and external stimuli,functioning as a sequential gate,have great potential for targeting different aspects of antitumor immunity.Herein,we construct a mannose-mo... Nanomaterials that can sequentially respond to internal and external stimuli,functioning as a sequential gate,have great potential for targeting different aspects of antitumor immunity.Herein,we construct a mannose-modified,pH and reactive oxygen species(ROS) sequential-responsive,transformable dualimmunofunction nanoprodrug(MpRTNP).This nanoprodrug encapsulates a transforming growth factor-β(TGF-β) receptor inhibitor SD-208(MpRTNP@SD),to simultaneously alleviate the immunosuppressive effects of TGF-β and tumor-associated macrophages(TAMs).In the weakly acidic tumor microenvironment(TME),the vesicle-micelle morphology transformation occurs owing to the protonation of PC7A,which is accompanied by SD-208 release to inhibit cancer-associated fibroblasts and regulatory T cells.The transformed micelles then target TAMs via mannose receptor-media ted endocytosis.Upon laser irradiation,the thioketal linker is cleaved,releasing conjugated chlorin e6 and generating ROS,which facilitates TAM polarization.The PC7A^(+) segment activates the stimulator of the interferon gene in TAMs with elevated phosphorylation of TANK binding kinase 1 and interferon regulatory factor 3,and type I interferon secretion.MpRTNP@SD displays superior abscopal effects and robust antitumor immunity,as evidenced by increased CD8^(+)/CD4^(+) T cell infiltration and reduced regulatory T cell(Treg) ratios.Mouse survival time is prolonged after combination with the CD47 antibody.This study provides a novel strategy for potent antitumor immunotherapy through pH and ROS sequential-gated spatiotemporal regulation of the TME. 展开更多
关键词 Drug delivery Stimulus-responsive nanoprodrug Tumor microenvironment modulation STING activation Cancer immunotherapy
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Scutellaria barbata D.Don extracts alleviate SARS-CoV-2 induced acute lung injury by inhibiting virus replication and bi-directional immune modulation
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作者 Yan Ran Zinuo Chen +4 位作者 Carolina Q.Sacramento Lingyuan Fan Qinghua Cui Lijun Rong Ruikun Du 《Virologica Sinica》 2025年第3期430-438,共9页
The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutel... The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutellaria barbata D.Don(SBD),against SARS-CoV-2 infection both in vitro and in vivo.Using a viral replicon particle(VRP)-based mouse model of SARS-CoV-2 infection,our study revealed that SBD extracts can reduce viral load in mouse lungs and alleviate the viral induced pneumonia.In vitro antiviral determination further validated the direct acting antiviral efficacy of SBD extracts against SARS-CoV-2 replication.Mechanistic studies demonstrated that SBD can act against SARS-CoV2 replication by targeting both 3-chymotrypsin-like and papain-like cysteine proteases,via a combination of multiple active constituents.Moreover,SBD can modulate the host inflammation response in a bi-directional manner,which also contribute to the mitigation of viral induced acute lung injury.In summary,our study provides SBD as a promising therapeutic agent to combat SARS-CoV-2 infections that merit further development. 展开更多
关键词 SARS-CoV-2 Scutellaria barbata D.Don ANTIVIRAL Bi-directional immune modulation
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Improved Spectral Amplitude Modulation Based on Sparse Feature Adaptive Convolution for Variable Speed Fault Diagnosis of Bearing
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作者 Jiawei Lin Changkun Han +3 位作者 Wei Lu Liuyang Song Peng Chen Huaqing Wang 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第1期31-43,共13页
Difficulty in extracting nonlinear sparse impulse features due to variable speed conditions and redundant noise interference leads to challenges in diagnosing variable speed faults.Therefore,an improved spectral amplit... Difficulty in extracting nonlinear sparse impulse features due to variable speed conditions and redundant noise interference leads to challenges in diagnosing variable speed faults.Therefore,an improved spectral amplitude modulation(ISAM)based on sparse feature adaptive convolution(SFAC)is proposed to enhance the fault features under variable speed conditions.First,an optimal bi-damped wavelet construction method is proposed to learn signal impulse features,which selects the optimal bi-damped wavelet parameters with correlation criterion and particle swarm optimization.Second,a convolutional basis pursuit denoising model based on an optimal bi-damped wavelet is proposed for resolving sparse impulses.A model regularization parameter selection method based on weighted fault characteristic amplitude ratio assistance is proposed.Then,an ISAM method based on kurtosis threshold is proposed to further enhance the fault information of sparse signal.Finally,the type of variable speed faults is determined by order spectrum analysis.Various experimental results,such as spectral amplitude modulation and Morlet wavelet matching,verify the effectiveness and advantages of the ISAM-SFAC method. 展开更多
关键词 bearing fault diagnosis feature enhancement sparse representation spectral amplitude modulation variable speed
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A Novel Secrecy Enhancing Scheme for Spatial Modulation in the Presence of Imperfect CSI
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作者 Shang Pingping Chen Junqi +4 位作者 Tao Zhuofan Xie Longhui Wan Xiangkui Guan Liang Qin Jiangyi 《China Communications》 2025年第6期291-299,共9页
Based on the objective reality of channel estimation error,this paper introduces a novel artificial noise(AN)aided spatial modulation(SM)secrecyenhancing scheme under imperfect channel state information(CSI).In the pr... Based on the objective reality of channel estimation error,this paper introduces a novel artificial noise(AN)aided spatial modulation(SM)secrecyenhancing scheme under imperfect channel state information(CSI).In the proposed scheme,SM is used to activate one antenna from the transmit antennas,and the information symbols will be transmitted with the designed AN at each timeslot.By utilizing the legitimate channel’s imperfect CSI,AN is generated across two adjacent timeslots.Because the CSI is known at the legitimate receiver,then it can perfectly cancel the AN.However,the eavesdropper knows nothing of the legitimate channel’s CSI,so it can not recover any useful information from the AN.At the receiver,a new detection scheme that detects across two adjacent timeslots is also proposed.With imperfect CSI,the secrecy rate of the proposed scheme is derived over Rayleigh fading channels in order to investigate the performance.Moreover,based on the secrecy performance analysis,the lower bound of the ergodic secrecy rate(ESR),the corresponding closed form of the lower bound,and the approximated expression are also derived.The simulation results verified in this paper prove that the proposed scheme with imperfect CSI can achieve satisfactory performance. 展开更多
关键词 artificial noise ergodic secrecy rate imperfect channel state information physical layer security spatial modulation
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Evaluation of Reinforcement Learning-Based Adaptive Modulation in Shallow Sea Acoustic Communication
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作者 Yifan Qiu Xiaoyu Yang +1 位作者 Feng Tong Dongsheng Chen 《哈尔滨工程大学学报(英文版)》 2026年第1期292-299,共8页
While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance re... While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance remains underexplored in field investigations.To evaluate the practical applicability of this emerging technique in adverse shallow sea channels,a field experiment was conducted using three communication modes:orthogonal frequency division multiplexing(OFDM),M-ary frequency-shift keying(MFSK),and direct sequence spread spectrum(DSSS)for reinforcement learning-driven adaptive modulation.Specifically,a Q-learning method is used to select the optimal modulation mode according to the channel quality quantified by signal-to-noise ratio,multipath spread length,and Doppler frequency offset.Experimental results demonstrate that the reinforcement learning-based adaptive modulation scheme outperformed fixed threshold detection in terms of total throughput and average bit error rate,surpassing conventional adaptive modulation strategies. 展开更多
关键词 Adaptive modulation Shallow sea underwater acoustic modulation Reinforcement learning
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基于HS-GC-IMS技术解析不同干燥工艺对西红花挥发性成分的影响
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作者 王嘉习 吴凤云 +7 位作者 张弛 骆紫义 洪丹尧 高爽 栾洁 巴剑波 陆颖洁 韩婷 《分析测试学报》 北大核心 2026年第1期50-60,共11页
该研究通过顶空-气相色谱-离子迁移谱(HS-GC-IMS)技术,对西红花鲜样和不同干燥方法(阴干、加热板干燥、烘箱干燥、真空干燥及冻干)样品中的75个挥发性化合物进行定性和相对定量分析,并构建了西红花挥发性成分的指纹图谱。通过聚焦于西... 该研究通过顶空-气相色谱-离子迁移谱(HS-GC-IMS)技术,对西红花鲜样和不同干燥方法(阴干、加热板干燥、烘箱干燥、真空干燥及冻干)样品中的75个挥发性化合物进行定性和相对定量分析,并构建了西红花挥发性成分的指纹图谱。通过聚焦于西红花不同干燥过程中挥发性成分的动态变化,运用主成分分析、偏最小二乘判别分析和聚类热图对样品进行识别和差异性分析,筛选出27种关键差异化合物,解析不同干燥工艺对西红花中挥发性成分的影响,揭示了不同干燥方法通过不同程度作用于西红花中物理(高温挥发)、化学(光热分解)、生化反应影响西红花中的挥发性成分,造成西红花药材品质的多样性。阴干样本中的挥发性成分种类最丰富,加热板干燥样本中的藏红花醛含量最高(2.91 mg/g),烘箱和真空干燥样本中的酯类和酮类丰度最高,冻干样本中的成分稳定性最高。研究可为未来根据实际应用场景选择不同的干燥方法提供理论指导。 展开更多
关键词 西红花 干燥工艺 挥发性成分 顶空-气相色谱-离子迁移谱 藏红花醛
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A Biomimetic Stress Field Modulation Strategy Inspired by Scorpion Compound Slit Sensilla Enabled High-Accuracy and Low-Power Positioning Sensor for Identifying the Load Incident Angles
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作者 Junqiu Zhang Yu Chen +11 位作者 Haoran Li Jiqi Gao Xiangbo Gu Jiachao Wu Xiaojing Qin Kejun Wang Bin Zhu Daobing Chen Tao Sun Jianhua Fan Zhiwu Han Luquan Ren 《Journal of Bionic Engineering》 2025年第2期727-738,共12页
Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rat... Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems. 展开更多
关键词 Scorpion Compound Slit Sensilla(SCSS) Vibration Source Stress Field modulation Strategy High-accuracy and low-power Positioning Sensor Minimum Positioning Unit(MPU)
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EM-based detection scheme for differential unitary space-time modulation
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作者 杜正锋 陈杰 +1 位作者 潘文 高西奇 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期484-488,共5页
The performance loss of an approximately 3 dB signal-to-noise ratio is always paid with conventional differential detection compared to the related coherent detection. A new detection scheme consisting of two steps is... The performance loss of an approximately 3 dB signal-to-noise ratio is always paid with conventional differential detection compared to the related coherent detection. A new detection scheme consisting of two steps is proposed for the differential unitary space-time modulation (DUSTM) system. In the first step, the data sequence is estimated by conventional unitary space-time demodulation (DUSTD) and differentially encoded again to produce an initial estimate of the transmitted symbol stream. In the second step, the initial estimate of the symbol stream is utilized to initialize an expectation maximization (EM)-based iterative detector. In each iteration, the most recent detected symbol stream is employed to estimate the channel, which is then used to implement coherent sequence detection to refine the symbol stream. Simulation results show that the proposed detection scheme performs much better than the conventional DUSTD after several iterations. 展开更多
关键词 unitary space-time modulation differential detection expectation maximization (EM) algorithm
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Adaptive modulation in MIMO optical wireless communication systems 被引量:1
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作者 吴斌 吴亮 邹采荣 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期175-180,共6页
In the intensity modulation and direct detection (IM/DD) multiple-input multiple-output (MIMO) optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee th... In the intensity modulation and direct detection (IM/DD) multiple-input multiple-output (MIMO) optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee the nonnegative property of transmitted signals, and the MIMO channel is converted to a parallel channel by using a singular value decomposition. Besides, a QR decomposition and successive interference cancellation based adaptive modulation scheme is proposed, and the MIMO channel can be simplified to a parallel channel under the bit error ratio (BER) target constraint. The power is optimally allocated to each sub-channel to maximize the data rate. Simulation results show that the proposed adaptive modulation schemes can effectively improve the transmission rate of the systems under the BER target and constant optical power constraints. The proposed adaptive modulation schemes make use of the multiplexing gain of the MIMO techniques, and can further improve the spectrum efficiency of optical wireless systems. 展开更多
关键词 optical wireless communication multiple inputand multiple output (MimO) adaptive modulation
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基于GC-IMS和GC-MS的发酵玉米粉挥发性风味成分分析
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作者 那治国 安宇桐 +1 位作者 于博洋 韩春然 《食品工业科技》 北大核心 2025年第24期343-354,共12页
本文通过以玉米碴为原料,酿酒酵母、嗜酸乳杆菌、枯草芽孢杆菌及纳豆芽孢杆菌作发酵剂,以单菌和组合的方式对玉米进行发酵制成玉米粉,采用气相-离子迁移谱(Gas-chromatography ion mobility spectrometry,GCIMS)和气相色谱-质谱联用(Gas... 本文通过以玉米碴为原料,酿酒酵母、嗜酸乳杆菌、枯草芽孢杆菌及纳豆芽孢杆菌作发酵剂,以单菌和组合的方式对玉米进行发酵制成玉米粉,采用气相-离子迁移谱(Gas-chromatography ion mobility spectrometry,GCIMS)和气相色谱-质谱联用(Gas Chromatography-Mass Spectrometry,GC-MS)方法对发酵玉米粉的挥发性风味成分进行分析。结果表明,GC-IMS共检出68种风味物质,包括醛类12种、醇类18种、酯类11种、酮类11种以及6种杂环类;根据图谱差异分析发现,发酵后玉米粉风味物质均发生变化,其醇类、酯类和酸类物质含量相对提高。GC-MS共检出59种风味物质,包含13种醛类、12种酯类、15种醇类、7种酸类、6种酮类和7种杂环类物质。两种技术共同检测出29种风味物质,其中正癸醛等10种醛类、5种醇类、2-壬酮、2-庚酮、己酸乙酯、甲酸甲酯、丁酸乙酯及4种酸类物质为发酵玉米粉的主要风味物质。根据香气含量分析,对比未发酵玉米粉,自然发酵水果香含量提高了24.64%,酿酒酵母发酵水果香和酒香含量分别提高了30.05%、85.05%,嗜酸乳杆菌发酵水果甜香和奶油蜂蜜香含量分别提高了36.56%、90.36%,枯草芽孢杆菌和纳豆芽孢杆菌发酵水果甜香花及苦杏仁香含量分别提高了18.05%、15.59%和38.68%、38.02%,组合发酵水果甜香花、草香含量分别提高了53.53%、48.08%,表明经过发酵制得的玉米粉风味独特。 展开更多
关键词 玉米粉 发酵 挥发性成分 GC-imS GC-MS
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Maximal capacity nonorthogonal pulse shape modulation 被引量:8
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作者 Chen Zhaonan Wang Hongxing +1 位作者 Liu Xiguo Zhong Peilin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第6期1699-1708,共10页
To improve spectral utilization of communication system, a novel nonorthogonal pulse shape modulation (NPSM) based on prolate spheroidal wave function (PSWF) is proposed. The modulation employs nonorthogonal PSWF ... To improve spectral utilization of communication system, a novel nonorthogonal pulse shape modulation (NPSM) based on prolate spheroidal wave function (PSWF) is proposed. The modulation employs nonorthogonal PSWF pulses to transmit information and it shows a higher capacity than traditional orthogonal modulations. The NPSM capacity under the constraint of finite input alphabet, which is determined by parameters of PSWF pulse, is derived. An optimiza- tion model for maximal capacity of NPSM is constructed and an exhaustive self-adapting gradient search algorithm for the model is proposed. A practical NPSM scheme with the maximal capacity is obtained by this search algorithm and it is proved to be superior to orthogonal signaling in the capacity. Our theoretical analysis is validated by numerical simulations and practical tests, and the results show that NPSM outperforms orthogonal modulations in the capacity and has a lower Peak-to-Average Power Ratio. 展开更多
关键词 capacity modulation ORTHOGONALITY Prolate spheroidal wave function Quadrature amplitude modulation
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Dynamic infrared scene simulation using grayscale modulation of digital micro-mirror device 被引量:7
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作者 Zhang Kai Huang Yong +1 位作者 Yan Jie Sun Li 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第2期394-400,共7页
Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by usin... Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by using the digital grayscale modulation method. The infrared image modulation model of a digital micro-mirror device (DMD) is established and then the infrared scene simulator prototype which is based on DMD grayscale modulation is developed. To evaluate its main parameters such as resolution, contrast, minimum temperature difference, gray scale, various DMD subsystems such as signal decoding, image normalization, synchronization drive, pulse width modulation (PWM) and DMD chips are designed. The infrared scene simulator is tested on a certain infrared missile seeker. The test results show preliminarily that the infrared scene simulator has high gray scale, small geometrical distortion and highly resolvable imaging resolution and contrast and yields high-fidelity images, thus being able to meet the requirements for the infrared scene simulation inside a laboratory. 展开更多
关键词 Digital grayscale modulation Digital micro-mirror device Gray scale image processing Infrared scene simulation MODELS Pulse width modulation
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