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In-situ Characterization of Non-aqueous Nano-dispersion Systems by Freeze-etching TEM and Comparative Study with Laser Scattering Method
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作者 欧忠文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期432-436,共5页
In-situ characterization of non-aqueous nano-dispersion systems(NANDS) by freeze-etching transmission electron microscope(FETEM) was reported.To improve just-for-once successive rate of specimen preparation and ge... In-situ characterization of non-aqueous nano-dispersion systems(NANDS) by freeze-etching transmission electron microscope(FETEM) was reported.To improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was developed.Size,distribution and morphology of NANDS were directly visualized.Some information of particle dispersion feature and particle density can also be obtained.Reproductivity of the FETEM characterization is excellent.Comparing with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle size.Moreover,FETEM can give dispersion feature of nanoparticle in non-aqueous medium. 展开更多
关键词 non-aqueous nano-dispersion system dispersion state in-situ characterization FREEZE-ETCHING laser scattering method
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Mechanisms of microbubble vibration in water-gas dispersion system enhancing microscopic oil displacement efficiency
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作者 ZHANG Moxi CHEN Xinglong +1 位作者 LYU Weifeng HAN Haishui 《Petroleum Exploration and Development》 2024年第6期1574-1586,共13页
Two etching models,the spherical-rod standard pore channel and the pore structure,were used to conduct displacement experiments in the water-gas dispersion system to observe the morphological changes and movement char... Two etching models,the spherical-rod standard pore channel and the pore structure,were used to conduct displacement experiments in the water-gas dispersion system to observe the morphological changes and movement characteristics of microbubbles.Additionally,numerical simulation methods were employed for quantitative analysis of experimental phenomena and oil displacement mechanisms.In the experiment,it was observed that microbubble clusters can disrupt the pressure equilibrium state of fluids within the transverse pores,and enhancing the overall fluid flow;bubbles exhibit a unique expansion-contraction vibration phenomenon during the flow process,which is unobservable in water flooding and gas flooding processes.Bubble vibration can accelerate the adsorption and expansion of oil droplets,and promote the emulsification of crude oil,thereby improving microscopic oil displacement efficiency.Combining experimental data with numerical simulation analysis of bubble vibration effects,it was found that microbubble vibrations exhibit characteristics of a sine function,and the energy release process follows an exponential decay pattern;compared to the gas drive front interface,microbubbles exhibit a significant“rigidity”characteristic;the energy released by microbubble vibrations alters the stability of the seepage flow field,resulting in significant changes to the flow lines;during the oil displacement process,the vast number of microbubbles can fully exert their vibrational effects,facilitating the migration of residual oil and validating the mechanism of the water-gas dispersion system enhancing microscopic oil displacement efficiency. 展开更多
关键词 water-gas dispersion system micro-etching model microbubble vibration elastic energy oil displacement mechanism
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Co-amorphous solid dispersion systems of lacidipine-spironolactone with improved dissolution rate and enhanced physical stability 被引量:2
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作者 Zhaomeng Wang Mengchi Sun +7 位作者 Tian Liu Zisen Gao Qing Ye Xiao Tan Yanxian Hou Jin Sun Dun Wang Zhonggui He 《Asian Journal of Pharmaceutical Sciences》 SCIE 2019年第1期95-103,共9页
Co-amorphous solid dispersion(C-ASD)systems have attracted great attention to improve the solubility of poorly soluble drugs,but the selection of an appropriate stabilizer to stabilize amorphous forms is still a huge ... Co-amorphous solid dispersion(C-ASD)systems have attracted great attention to improve the solubility of poorly soluble drugs,but the selection of an appropriate stabilizer to stabilize amorphous forms is still a huge challenge.Herein,C-ASD system of two clinical combined used drugs(lacidipine(LCDP)and spironolactone(SPL))as stabilizers to each other,was prepared by solvent evaporation method.The effects of variation in molar ratio of LCDP and SPL(3:1,1:1,1:3,1:6,and 1:9)on the drug release characteristics were explored.Polarized light microscopy(PLM),powder X-ray diffraction(PXRD),differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA)were employed to evaluate the solid states.Prepared C-ASDs were further studied for their stability under the high humidity(RH 92.5%).Further analysis of C-ASDs via Fourier-transform infrared spectroscopy(FTIR)and Raman spectroscopy confirmed that hydrogen bond interactions between the two drugs played a significant role in maintaining the stability of the C-ASDs systems.Moreover,molecular dynamic(MD)simulations provided a clear insight into the stability mechanism at the molecular level.This study demonstrated the novel drug-drug C-ASDs systems is a promising formulation strategy for improved dissolution rate and enhanced physical stability of poorly soluble drugs. 展开更多
关键词 Co-amorphous solid dispersion LACIDIPINE SPIRONOLACTONE Stability Molecular dynamic(MD) simulations
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Simulation analysis and implementation of spectral dispersion system based on virtually imaged phased array 被引量:1
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作者 YANG Dan LIU Jin-tao +3 位作者 FAN Xue-ke ZHU Wai-hui WANG Shuai SONG Xiao-quan 《Optoelectronics Letters》 EI 2020年第4期268-271,共4页
Virtually imaged phased array(VIPA)has the advantages of insensitive to polarization,simple structure and high in spectral resolution.Compared with commonly used dispersive devices,such as diffraction gratings or Fabr... Virtually imaged phased array(VIPA)has the advantages of insensitive to polarization,simple structure and high in spectral resolution.Compared with commonly used dispersive devices,such as diffraction gratings or Fabry-Perot(FP)interferometers,VIPA is self-aligned and has high transmission efficiency.In this paper,the dispersion mechanism of the VIPA is introduced in detail,the influence of incident angle and VIPA thickness on the dispersion performance near 532 nm is calculated and analyzed with MATLAB.According to the calculated results,the selected VIPA device has a thickness of 6 mm and an incident angle of 4°.The spectral dispersion system,in combination with corresponding optical devices,is designed and simulated with ZEMAX,then the experimental system was built.The spectral dispersion system based on VIPA,at a central wavelength of 532 nm,has the free spectral range of 15.08 GHz and the spectral resolution of 0.87 GHz.The system designed in this paper can be applied to high-resolution spectral detection such as Brillouin scattering,Raman scattering,laser fluorescence,laser-induced plasma and so on. 展开更多
关键词 VIPA dispersion system
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Development of self-micellizing solid dispersion system employing amphipathic copolymer for the improvement of dissolution and oral bioavailability of cyclosporine A
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作者 Hiroki Suzuki Hideyuki Sato +5 位作者 Yoshiki Kojo Takahiro Mizumoto Kayo Yuminoki Naohumi Hashimoto Yoshiki Seto Satomi Onoue 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期50-51,共2页
The main objective of the present study is to develop a selfmicellizing solid dispersion(SMSD)system of cyclosporine A(CsA)using an amphiphilic copolymer,poly[MPC-co-BMA](pMB)to improve the biopharmaceutical propertie... The main objective of the present study is to develop a selfmicellizing solid dispersion(SMSD)system of cyclosporine A(CsA)using an amphiphilic copolymer,poly[MPC-co-BMA](pMB)to improve the biopharmaceutical properties of CsA(Fig.1A).Unlike conventional carrier compounds,pMB would perform the bifunctional ability as both polymeric carrier of solid dispersion system and solubilizer derived from a high micellizing property,which could be considered beneficial for the production of highly water soluble formulation of poorly water soluble compound[1].Improvement in the aqueous solubility has been believed to be a key consideration for acquiring potent pharmacological effects of BCS class II drug like CsA. 展开更多
关键词 CYCLOSPORINE A AMPHIPATHIC COPOLYMER Self-micellizing solid dispersion Oral BIOAVAILABILITY
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Mathematical modeling of the bellows dispersion system of submunitions
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作者 师娇 唐胜景 高峰 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期23-30,共8页
A mathematical model of the bellows dispersion system is developed by combining the interior ballistic theory with structural dynamics theory to describe the deformation course of bellows. By analyzing the physical mo... A mathematical model of the bellows dispersion system is developed by combining the interior ballistic theory with structural dynamics theory to describe the deformation course of bellows. By analyzing the physical model of the bellows dispersion system, the dispersion course is divided into three stages. For each stage, mathematical model is built and its terminal conditions are given. The numerical simulation is based on the Runge-Kutta method and differential quadrature method. Simulation results of the model agree with those of the model built by only interior ballistics theory. However, this model is congruous with the actual dispersion course and can more easily determine the dispersion time and submunition displacement. 展开更多
关键词 mathematical model differential quadrature method DEFORMATION dispersion submu- nitions
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CONTROLLED/"LIVING" RADICAL POLYMERIZATION OF STYRENE IN AN AQUEOUS DISPERSION SYSTEM
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作者 Bin Zhang Zhao-bin Zhang +2 位作者 Xiao-long Wan Chun-pu Hu Sheng-kang Ying Lab of Living Polymerization, East China University of Science and Technology.Shanghai 200237,China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第5期445-451,共7页
Atom transfer radical polymerization (ATRP) of styrene catalyzed by cuprous (CuX)/1,10-phenanthroline (Phen) and CuX/CuX2/Phen was conducted in an aqueous dispersed system. A stable latex was obtained by using ionic s... Atom transfer radical polymerization (ATRP) of styrene catalyzed by cuprous (CuX)/1,10-phenanthroline (Phen) and CuX/CuX2/Phen was conducted in an aqueous dispersed system. A stable latex was obtained by using ionic surfactant sodium lauryl sulfonate (SLS) or composite surfactants, such as SLS/polyoxyethylene nonyl phenyl ether (OP-10), SLS/hexadecanol and SLS/OP-10/hexadecanol, Among which SLS and SLS/OP-10/hexadecanol systems established better dispersed effect during the polymerization, It was found that Phen was a more suitable ligand than N,N,N',N',N'-pentamethyldiethylenetriamine (PMDETA) to maintain an appropriate equilibrium of the activator Cu(I) and the deactivator Cu(II) between the organic phase and the water phase, The effect of several initiators (such as EBiB, CCl4 and 1-PEBr) and the temperature on such a kind of ATRP system was also observed. The number-average molar mass (M-n) of polystyrene (PS) increased with the conversion and the molar mass distribution (M-w/M-n) remained narrow. These experimental data show that the polymerization could be controlled except for the quick increase of monomer conversion and the number-average molar mass of PS in the initial stage of polymerization. Furthermore, the initiator efficiency was found to be low (similar to57%) in CuX/Phen catalyzed system. To overcome this problem, Cu(II)X-2 (20 mol%-50 mol% based on CuX) was introduced into the polymerization system. In this case, higher initiator efficiency (60%-90%), low M-w/M-n of PS (as low as 1.08) were achieved and the molar masses of the PS fit with the theoretical ones. 展开更多
关键词 controlled/'living' radical polymerization POLYSTYRENE water dispersed polymerization 1 10-PHENANTHROLINE
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A Global Investigation About Hard Core Attractive Yukawa Approximation and Adhesive Hard Sphere Approximation for Structure of Colloidal Dispersion Systems
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作者 ZHOUShi-Qi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期567-576,共10页
The accuracy of hard core attractive Yukawa (HCAY) potential and adhesivehard sphere (AH) potential in representing the structure factor of short range square well potentialand Asakura and Oosawa (AO) depletion potent... The accuracy of hard core attractive Yukawa (HCAY) potential and adhesivehard sphere (AH) potential in representing the structure factor of short range square well potentialand Asakura and Oosawa (AO) depletion potential is examined by comparing theoretical predictionswith the existing simulation data and the present numerical results from the non-linear optimizedrandom phase approximation closure for Ornstein—Zernike equation. For the case of square-well (SW)potential, it is shown that the structure factor of HCAY potential based on a recently proposedsemi-analytical expression for the radial distribution function can describe the structure factor ofSW potential with reduced well width λ ≤ 2 only if the reduced contact potential βε_(sw) ≤0.25, while the analytical expression for the structure factor of AH potential under Percus-Yevick(PY) approximation completely fails for the case of λ 】 1.2. For the case of AO depletionpotential, the domain of validity of both HCAY potential and AH potential is complementary. With theabove analysis and considering the solid-liquid transition of the AH potential with an adhesiveparameter τ below 1.31 cannot be predicted by modified weighted density approximation, the roleplayed by the HCAY potential about the mapping manipulation should not be ignored. 展开更多
关键词 colloidal dispersion structure factor
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Adaptive Dispersion Estimation for Linearized Electronic Dispersion Compensation in IM-DD Systems
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作者 Huo Jiahao Tao Jianlong +3 位作者 Zhang Xiaoying Zhu Jin Qin Peng Wei Huangfu 《China Communications》 2025年第4期55-64,共10页
An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in... An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in the intensity-modulation and direct-detection(IM-DD)system,improving the tolerance of the algorithm to chromatic dispersion(CD).In order to address the divergence arising from the perturbation in the amplitude of the received signal caused by the filtering effect of the non-ideal channels,a channel-compensation equalizer(CCE)derived from the back-to-back(BTB)scenario is employed at the transmitter to make the amplitude of the received signal depicting the CD effect more accurately.The simulation results demonstrate the essentiality of CCE for the convergence and performance improvement of the G-S algorithm.Results show that it supports 112Gb/s four-level pulse amplitude modulation(PAM4)over 100 km standard single-mode fiber(SSMF)transmission under the 7%forward error correction(FEC)threshold of 3.8E-3.Besides,ADE improves the tolerance to wavelength drift from about 4 nm to 42 nm,and there is a better tolerance for fiber distance perturbation,indicating the G-S algorithm and its derived algorithms with the ADE scheme exhibit superior robustness to the perturbation in the system. 展开更多
关键词 chromatic dispersion digital signal process intensity modulation and direct detection
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Fault diagnosis of rolling bearing based on two-dimensional composite multi-scale ensemble Gramian dispersion entropy
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作者 Wenqing Ding Jinde Zheng +3 位作者 Jianghong Li Haiyang Pan Jian Cheng Jinyu Tong 《Chinese Journal of Mechanical Engineering》 2026年第1期125-144,共20页
One-dimensional ensemble dispersion entropy(EDE1D)is an effective nonlinear dynamic analysis method for complexity measurement of time series.However,it is only restricted to assessing the complexity of one-di-mension... One-dimensional ensemble dispersion entropy(EDE1D)is an effective nonlinear dynamic analysis method for complexity measurement of time series.However,it is only restricted to assessing the complexity of one-di-mensional time series(TS1d)with the extracted complexity features only at a single scale.Aiming at these problems,a new nonlinear dynamic analysis method termed two-dimensional composite multi-scale ensemble Gramian dispersion entropy(CMEGDE_(2D))is proposed in this paper.First,the TS_(1D) is transformed into a two-dimensional image(I_(2D))by using Gramian angular fields(GAF)with more internal data structures and geometri features,which preserve the global characteristics and time dependence of vibration signals.Second,the I2D is analyzed at multiple scales through the composite coarse-graining method,which overcomes the limitation of a single scale and provides greater stability compared to traditional coarse-graining methods.Subsequently,a new fault diagnosis method of rolling bearing is proposed based on the proposed CMEGDE_(2D) for fault feature ex-traction and the chicken swarm algorithm optimized support vector machine(CsO-SvM)for fault pattern identification.The simulation signals and two data sets of rolling bearings are utilized to verify the effectiveness of the proposed fault diagnosis method.The results demonstrate that the proposed method has stronger dis-crimination ability,higher fault diagnosis accuracy and better stability than the other compared methods. 展开更多
关键词 Composite multi-scale ensemble Gramian dispersion entropy dispersion entropy Fault diagnosis Rolling bearing Feature extraction
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Solid dispersion of BIBR1532:A potent therapeutic for oesophageal squamous cancer
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作者 Xue-Juan Zhang Nai-Xuan Deng +4 位作者 Huan-Qing Zhang Jie-Zuan Cen Zi-Xuan Zheng Meng-Qin Guo Zheng-Wei Huang 《World Journal of Gastrointestinal Oncology》 2026年第1期291-295,共5页
This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activat... This letter addresses challenges in the clinical translation of BIBR1532,a promising telomerase inhibitor,for the treatment of esophageal squamous cell carcinoma(ESCC).BIBR1532 exerts its anti-cancer effect by activating DNA damage response(ATR/CHK1 and ATM/CHK2)pathways and downregulating telomere-binding proteins.Although its therapeutic potential is limited by poor aqueous solubility,solid dispersion(SD)technology may overcome this obstacle.Systematic analysis using PubChem-derived simplified molecular input line entry system identifiers and artificial intelligence-driven FormulationDT platform evaluation(oral formulation feasibility index:0.38)revealed that the SD technology,with superior scalability(32 approved products by 2021)and lower production risks,outperforms lipid-based formulations as an optimal dissolution strategy.Material analysis revealed hydroxypropyl methylcellulose(HPMC)as the optimal carrier with lower hygroscopicity,higher temperature and no intestinal targeting,thus enabling ESCC therapy.HPMC-based SD enhances BIBR1532 solubility and bioavailability for effective ESCC treatment.Future studies should focus on pilot tests for SD fabrication. 展开更多
关键词 BIBR1532 SOLUBILITY Solid dispersion Oesophageal squamous cancer Hydroxypropyl methylcellulose Druggability
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Comprehensive Analysis of the Relative Dispersion of Droplet-Size Distributions and Their Relationships to Key Physical Fog Processes Under Different Aerosol Conditions and Evolutionary Stages
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作者 Xingcan JIA Chunsong LU +7 位作者 Zhiheng LIAO Ping TIAN Yuan WANG Fei WANG Shuai YANG Youjun DOU Xiange LIU Yangang LIU 《Advances in Atmospheric Sciences》 2026年第4期861-873,I0042-I0046,共18页
The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with... The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with limited studies on fog,particularly those that examine the combined influences of all key physical processes and their roles during fog evolution.As such,this study aims to conduct a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables,as well as the underlying microphysical and dynamic processes,based on field fog campaigns in polluted and clean conditions.In polluted fog,droplet concentrations are higher,leading to smaller droplets and increased dispersion.The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog,but shifts to negative in clean fog.We attribute the difference to various microphysical processes like aerosol activation,condensation,collision-coalescence,and entrainment-mixing.In polluted fog,high aerosol concentrations,low supersaturations,and strong turbulence(entrainment-mixing)provide suitable conditions for the simultaneous occurrence of droplet condensation and aerosol activation,resulting in a positive correlation between dispersion and volume-mean radius,especially during the fog formation stage.In contrast,during the mature stage in clean fog,condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius.The collision-coalescence process is more active in the mature stage,increasing radii and leading to the negative correlation between dispersion and volume-mean radius.This result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds. 展开更多
关键词 FOG relative dispersion evolutionary stage aerosol activation collision-coalescence
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Overcoming oxidation and enhancing dispersion of nanoparticles via molten salt:Configurational distribution of TiC_(np)in pure Mg
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作者 Xuanchang Zhang Xiaojun Wang +5 位作者 Nodir Turakhodjaevr Xuejian Li Hailong Shi Yuanyuan Zhang Xiaoshi Hu Chao Xu 《Journal of Magnesium and Alloys》 2026年第1期138-148,共11页
Nanoparticle-reinforced Mg matrix composites(NPMMCs)capitalize on the synergistic properties of nanoparticles and Mg matrix,resulting in enhanced mechanical attributes compared to matrix.Nonetheless,effective high-tem... Nanoparticle-reinforced Mg matrix composites(NPMMCs)capitalize on the synergistic properties of nanoparticles and Mg matrix,resulting in enhanced mechanical attributes compared to matrix.Nonetheless,effective high-temperature dispersion of nanoparticles remains challenging.This study employs a molten salt dispersant(NaCl-KCl-MgCl_(2))effectively mitigating the oxidation and combustion of TiC nanoparticles(TiC_(np)).Compared with the atmosphere,the molten salt facilitates the pre-dispersion of TiC_(np)through thermal motion at elevated temperatures,thereby reducing agglomeration between the TiC_(np).Simultaneously,the molten salt effectively wets and disrupts the oxide layer on the surface of Mg melt,facilitating the wetting of TiC_(np)by the Mg melt.The successful incorporation of 3 vol.%TiC_(np)into the Mg matrix is achieved by utilizing molten salt,and the addition of TiC_(np)increases the viscosity of mg melt.Further dispersed by ultrasonic dispersion,the unique distribution of TiC_(np)within ring-like structures was obtained which was attributed to the increase of viscosity.As a configurational distribution,the ring-like TiC_(np)distribution morphology significantly enhances the mechanical properties of composites,as evidenced by an approximate 50%increase in compressive strength(UCS). 展开更多
关键词 Molten salt Mg composites Ultrasonic dispersion Tic nanoparticles HETEROSTRUCTURE
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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Detection of white matter microstructural changes in patients with systemic lupus erythematosus based on multiple diffusion models and related diffusion metrics
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作者 Zhenxing Li Huanhuan Li +5 位作者 Bailing Tian Huiyang Liu Yueluan Jiang Pingting Yang Guoguang Fan Hu Liu 《Neural Regeneration Research》 2026年第6期2467-2474,共8页
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle... Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms. 展开更多
关键词 diffusion kurtosis imaging diffusion tensor imaging mean apparent propagator neurite orientation dispersion and density imaging neuropsychiatric systemic lupus erythematosus return to axis probability return to origin probability superior longitudinal fasciculus-3 superior thalamic radiation tract-based spatial statistics white matter microstructure
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Separation of Eu(Ⅲ) with supported dispersion liquid membrane system containing D2EHPA as carrier and HNO_3 solution as stripping solution 被引量:5
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作者 裴亮 王理明 于国强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第1期7-14,共8页
The Eu(III) separation in supported dispersion liquid membrane (SDLM), with polyvinylidene fluoride membrane (PVDF) as the support and dispersion solution containing HNO3 solution as the stripping solution and D... The Eu(III) separation in supported dispersion liquid membrane (SDLM), with polyvinylidene fluoride membrane (PVDF) as the support and dispersion solution containing HNO3 solution as the stripping solution and Di(2-ethylhexyl) phosphoric acid (D2EHPA) dis- solved in kerosene as the membrane solution, was studied. The effects ofpH value, initial concentration of Eu(III) and different ionic strengths in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HNO3 solution, concentration of carrier, different stripping agents in the dispersion phase on the separation of Eu(III) were also investigated, respectively. As a result, the optimum separation conditions of Eu(III) were obtained as the concentration of HNO3 solution was 4.00 mol/L, concentration of D2EHPA was 0.160 mol/L, and volume ratio of membrane solution to stripping solution was 30:30 in the dispersion phase, and pH value was 5.00 in the feed phase. Ionic strength had no obvious effect on the separation of Eu(III). Under the optimum conditions studied, when initial concentration of Eu(III) was 1.00× 10^-4 mol/L, the separation rate of Eu(III) was up to 94.2% during the separation period of 35 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The results were in good agreement with the literature data. 展开更多
关键词 supported dispersion liquid membrane Di(2-ethylhexyl) phosphoric acid europium(III) dispersion phase separation flux separation rate
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A New Fire Detection Method Using a Multi-Expert System Based on Color Dispersion, Similarity and Centroid Motion in Indoor Environment 被引量:10
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作者 Teng Wang Leping Bu +2 位作者 Zhikai Yang Peng Yuan Jineng Ouyang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期263-275,共13页
In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space... In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space is used to extract pre-detected regions instead of traditional motion differential method, as it’s more suitable for fire detection in indoor environment. Secondly, according to the flicker characteristic of the flame, similarity and two main values of centroid motion are proposed. At the same time, a simple but effective method for tracking the same regions in consecutive frames is established. Thirdly,a multi-expert system consisting of color component dispersion,similarity and centroid motion is established to identify flames.The proposed method has been tested on a very large dataset of fire videos acquired both in real indoor environment tests and from the Internet. The experimental results show that the proposed approach achieved a balance between the false positive rate and the false negative rate, and demonstrated a better performance in terms of overall accuracy and F standard with respect to other similar fire detection methods in indoor environment. 展开更多
关键词 Color dispersion centroid motion expert system RGB-HIS color model SIMILARITY video fire detection
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The Effect of Hydrostatic Pressure Fields on the Dispersion Characteristics of Fluid-shell Coupled System 被引量:4
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作者 刘志忠 李天匀 +1 位作者 朱翔 张俊杰 《Journal of Marine Science and Application》 2010年第2期129-136,共8页
The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Num... The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Numerical analysis was applied to solve the dispersion equations for shells filled with or loaded with fluid at various hydrostatic pressures.The results for external pressure showed that non-dimensional axial wave numbers are nearly independent when the pressure is below the critical level.The influence of internal pressure on wave numbers was found significant for the real branch s=1 and the complex branches of dispersion curves.The presence of internal pressure increased the cut on frequencies for the branch s=1 for high order wave modes. 展开更多
关键词 hydrostatic pressure dispersion fluid-shell coupled system wave propagation
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High-speed polarization mode dispersion compensation in a 43-Gb/s RZ-DQPSK transmission system over 1200 km of standard single-mode fibre 被引量:3
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作者 田凤 张晓光 +3 位作者 翁轩 席丽霞 张阳安 张文博 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期143-149,共7页
This paper reports that the designed optical polarization mode dispersion compensator shows a good performance under the real-time variation of differential group delay, state of polarization and principal state of po... This paper reports that the designed optical polarization mode dispersion compensator shows a good performance under the real-time variation of differential group delay, state of polarization and principal state of polarization in a (40×43)-Gb/s dense-wavelength-multiplexing, 1200-km enhanced return-to-zero differential-quadrature-phase-shift- keying (RZ-DQPSK) system. The polarization mode dispersion tolerance of the system is improved by 26 ps using the optical polarization mode dispersion compensator. The short and long time stabilities are tested with the bit error ratio recorded. 展开更多
关键词 optical polarization mode dispersion compensator polarization mode dispersion toler-ance bit error ratio forward error correction
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Dispersion compensation in an open-loop all-optical chaotic communication system 被引量:3
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作者 刘慧杰 任斌 冯久超 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期138-144,共7页
The optical chaotic communication system using open-loop fiber transmission is studied under strong injection conditions. The optical chaotic communication system with open-loop configuration is studied using fiber tr... The optical chaotic communication system using open-loop fiber transmission is studied under strong injection conditions. The optical chaotic communication system with open-loop configuration is studied using fiber transmission under strong injection conditions. The performances of fiber links composed of two types of fiber segments in different dispersion compensation maps are compared by testing the quality of the recovered message with different bit rates and encrypted by chaotic modulation (CM) or chaotic shift keying (CSK). The result indicates that the performance of the pre-compensation map is always worst. Two types of symmetrical maps are identical whatever the encryption method and bit-rate of message are. For the transmitting and the recovering of message of lower bit rate (1 Gb/s), the post-compensation map is the best scheme. However, for the message of higher bit rate (2.5 Gb/s), the parameters in communication system need to be modified properly in order to adapt to the high-speed application. Meanwhile, two types of symmetrical maps are the best scheme. In addition, the CM method is superior to the CSK method for high-speed applications. It is in accordance with the result in a back-to-back configuration system. 展开更多
关键词 chaotic communication dispersion compensation semiconductor lasers strong injection open-loop configuration
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