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Identifying the best common factor model via exploratory eactor analysis

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 24-33页

作者： he Bao-hua TANG Rui TAGN qi-yi School of Big Data Fuzhou University of International Studies and TradeFuzhou 350202China School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China Department of Computer Science University of BathUK Institute of Insect Science Zhejiang UniversityHangzhou 310058China.

Currently,there is no solid criterion for judging the quality of the estimators in factor *** paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor *** proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor *** are presented to demonstrate how the method is implemented and to verify its effectiveness.

关键词： factor analysis Shapiro-Wilk normality residuals

Low-temperature chemistry in plasma-driven ammonia oxidative pyrolysis

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Green Energy & Environment 2024年第9期9卷 1477-1488页

作者： Mingming Zhang qi Chen Guangzhao Zhou Jintao Sun he Lin School of Mechanical Electronic and Control Engineering Beijing Jiaotong University School of Mechanical Engineering Shanghai Jiao Tong University

Ammonia is gaining increasing attention as a green alternative fuel for achieving large-scale carbon emission reduction. Despite its potential technical prospects, the harsh ignition conditions and slow flame propagation speed of ammonia pose significant challenges to its application in engines. Non-equilibrium plasma has been identified as a promising method, but current research on plasma-enhanced ammonia combustion is limited and primarily focuses on ignition characteristics revealed by kinetic models. In this study, low-temperature and low-pressure chemistry in plasma-assisted ammonia oxidative pyrolysis is investigated by integrated studies of steady-state GC measurements and mathematical simulation. The detailed kinetic mechanism of NH3decomposition in plasma-driven Ar/NH3and Ar/NH3/O2mixtures has been developed. The numerical model has good agreements with the experimental measurements in NH3/O2consumption and N2/H2generation, which demonstrates the rationality of modelling. Based on the modelling results, species density profiles, path flux and sensitivity analysis for the key plasmaproduced species such as NH2, NH, H2, OH, H, O, O（1D）, O2（a1△g）, O2（b1∑g+）, Ar*, H-, Ar+, NH3+, O2-in the discharge and afterglow are analyzed in detail to illustrate the effectiveness of the active species on NH3excitation and decomposition at low temperature and relatively higher E/N values. The results revealed that NH2, NH, H as well as H2are primarily generated through the electron collision reactions e + NH3→ e + NH2+ H, e + NH3→ e + NH + H2and the excited-argon collision reaction Ar*+ NH3+ H → Ar + NH2+ 2H, which will then react with highly reactive oxidative species such as O2*, O*, O, OH, and O2to produce stable products of NOx and H2O. NH3→ NH is found a specific pathway for NH3consumption with plasma assistance, which further highlights the enhanced kinetic effects.

关键词： Non-equilibrium plasma Ammonia fuel Oxidative pyrolysis Pathway flux analysis Sensitivity analysis

Friction between Strongly Compressed Polymer Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1368-1374,I0008页

作者： qi Liao Institute of Chemistry Chinese Academy of SciencesBejing 100190China

We present the results of molecular dynamics simulations of steady shear between a pair of neutral polymer brushes,as well as a pair of charged polymer brushes in the strongly compressed *** results of the molecular dynamic simulations of neutral and polyelectrolyte brushes in implicit solvent including normal forces,shear forces,viscosities and friction coefficients as a function of separation between brushes,are presented in the *** comparison of the simulation results of neutral and charged brushes shows that the charged brushes is in the quasi-neutral regime,and the dependence of viscosity on the separation distance show the similar power law of neutral *** simulation results confirm that the implicit solvent simulations of polyelectrolyte brushes that ignore hydrodynamics interaction are in agreement with the scaling predictions qualitatively because of screening of hydrodynamic interaction and long-range electrostatic interactions on the correlation length *** of neutral and charged brushes show the lubrication properties that the friction coefficient decreases with the separation decreases at enough large ***,a maximum of friction coefficients is observed for polyelectrolyte brushes,which is in contrast to the neutral brushes with monotonical dependence.

关键词： Polymer brush Frictions coefficient Polyelectrolyte Lubrication

Propylene epoxidation coupled with furfural oxidation over Pt(Ⅱ?) TPP porphyrin with molecular oxygen

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Green Chemical Engineering 2024年第4期5卷 519-525页

作者： Hong-qi Li Hai-Yang Yu Yang Li Xiao-qi he Xian-Tai Zhou Huizhou Research Institute Sun Yat-sen University School of Chemical Engineering and Technology Sun Yat-sen University

The development of green route for preparing propylene oxide (PO) with molecular oxygen is of significance both in academic and industrial. In this work, propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin (Pt (II)TPP) has been developed. Propylene conversion and PO selectivity reached up to 56%and 83%, respectively. Meanwhile, furfural was almost completely converted to furoic *** on operando characterizations and electron paramagnetic resonance (EPR) tests, a mechanism involved high-valent Pt species was proposed. This work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry.

关键词： Propylene Epoxidation Molecular oxygen Furfural Platinum porphyrins

Multi-party privacy-preserving decision tree training with a privileged party

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Science China(Information Sciences) 2024年第8期67卷 253-268页

作者： Yiwen TONG qi FENG Min LUO Debiao he Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Cyber Science and Engineering Wuhan University Shanghai Technology Innovation Centre of Distributed Privacy-Preserving Artificial Intelligence Matrix Elements Technologies Key Laboratory of Computing Power Network and Information Security Ministry of EducationShandong Computer Science Center Qilu University of Technology(Shandong Academy of Sciences)

Currently, a decision tree is the most commonly used data mining algorithm for classification tasks. While a significant number of studies have investigated privacy-preserving decision trees, the methods proposed in these studies often have shortcomings in terms of data privacy breach or efficiency. Additionally,these methods typically only apply to symmetric frameworks, which consist of two or more parties with equal privilege, and are not suitable for asymmetric scenarios where parties have unequal privilege. In this paper,we propose SecureCART, a three-party privacy-preserving decision tree training scheme with a privileged party. We adopt the existing pMPL framework and design novel secure interactive protocols for division,comparison, and asymmetric multiplication. Compared to similar schemes, our division protocol is 93.5–560.4× faster, with the communication overhead reduced by over 90%; further, our multiplication protocol is approximately 1.5× faster, with the communication overhead reduced by around 20%. Our comparison protocol based on function secret sharing maintains good performance when adapted to pMPL. Based on the proposed secure protocols, we implement SecureCART in C++ and analyze its performance using three real-world datasets in both LAN and WAN environments. he experimental results indicate that SecureCART is significantly faster than similar schemes proposed in past studies, and that the loss of accuracy while using SecureCART remains within an acceptable range.

关键词： privacy protection decision trees secure multi-party computation secret sharing privileged party

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan WANG Jiang WANG Shaoming he Fei WANG qi WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

Light/pH dual-responsive magnetic metal-organic frameworks composites for phosphorylated peptide enrichment

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Chinese Chemical Letters 2024年第7期35卷 222-226页

作者： Rui Wang he qi Haijiao Zheng qiong Jia College of Chemistry Jilin UniversityChangchun 130012China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)combined with specific ligands are highly adaptable smart materials that can respond to external and physiological *** this study,we introduced a pyridinyl zwitterionic ligand with light/pH dual response into magnetic MOF composite(Fe_(3)O_(4)@ZW-MOF)for enrichment of phosphorylated peptides for the first *** introduction of the developed ligand gives MOF material dual response *** stimulation affects the generation/disappearance of free radicals of the pyridine derivative,resulting in a change in the charge gradient of the zwitterion,and zwitterion can also regulate the p H of the solution by adding acid or ***,the reversible capture and release of phosphorylated peptides can be easily achieved by adjusting light and *** established phosphorylated peptide enrichment platform exhibits high sensitivity(detection limit of 1 fmol),high selectivity(β-casein:BSA,1:1000),and good reusability(7 cycles).In addition,the method was applied to the enrichment of phosphorylated peptides in complex systems(non-fat milk and human serum),demonstrating the feasibility of this method for phosphoproteom *** conclusion,the synthesized Fe_(3)O_(4)@ZW-MOF is a promising MOF material,which provides the possibility to advance the application of responsive MOFs materials in proteomics.

关键词： Light pH Dual-response Metal-organic frameworks Phosphorylated peptide

Role of polarization evolution in the hysteresis effect of Pb-based antiferroelecrtics

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Chinese Chemical Letters 2024年第4期35卷 516-519页

作者： Botao Gao he qi Hui Liu Jun Chen Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201899China Hainan University Haikou 570228China

The electric field-induced irreversible domain wall motion results in a ferroelectric(FE) hysteresis. In antiferroelectrics(AFEs), the irreversible phase transition is the main reason for the hysteresis effects, which plays an important role in energy storage performance. Compared to the well-demonstrated FE hysteresis,the structural mechanism of the hysteresis in AFE is not well understood. In this work, the underlying correlation between structure and the hysteresis effect is unveiled in Pb(Zr,Sn,Ti)O_(3) AFE system by using in-situ electrical biasing synchrotron X-ray diffraction. It is found that the AFE with a canting dipole configuration, which shows a continuous polarization rotation under the electric field, tends to have a small hysteresis effect. It presents a negligible phase transition, a small axis ratio, and electric field-induced lattice changing, small domain switching. All these features together lead to a slim hysteresis loop and a high energy storage efficiency. These results offer a deep insight into the structure-hysteresis relationship of AFEs and are helpful for the design of energy storage material.

关键词： Antiferroelectric Hysteresis effect Structure refinement Perovskite In situ synchrotron radiation

Chemiluminescence determination of melamine with Luminol-K_3Fe(CN)_6 system

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Journal of Pharmaceutical Analysis 2011年第2期1卷 104-107页

作者： Xiao- Shuang Tang Xi-Yan Shi Yu-Hai Tang Zhong-Jin Yue qi-qi he The Second Affiliated Hospital Lanzhou University Lanzhou 730030 China Institute of Analytical Sciences Xi'an Jiaotong University. Xi'an 710061 China.

A sensitive chemiluminescence（CL） method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe（CN）6 system in alkaline medium. The determination conditions were optimized. Under optimum conditions, the chemiluminescence intensity had a good linear relationship with melamine in the range of 9.0 × 10^-9 - 7.0 × 10^-6 g/mL with a correlation coefficient of 0. 9992. The detection limits （3o） were 3.54 ng/mL for urine sample and 6.58 ng/mL for plasma sample. The average recoveries of melamine were 102.6% for urine sample and 95.1% for plasma sample. Melamine in samples was extracted with liquid-liquid extraction procedures and the assay results coincided very well with that determined with flow injection chemiluminescence method. The method provides a reproducible and stable approach for sensitive detection and quantification of melamine in urine and plasma samples.

关键词： chemiluminescence flow injection melamine urine plasma