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A practical synthesis of bis(indolyl)methanes catalyzed by BF_3·Et_2O

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Chinese Chemical Letters 2014年第3期25卷 406-410页

作者： Xia-fei Xu Yan Xiong Xue-Ge ling Xi-mi Xie Jie Yuan Shu-Ting Zhang Zhong-Rong Song School of Chemistry and Chemical Engineering Chongqing University State Key Laboratory of Elemento-organic Chemistry Nankai University School of Materials and Chemical Engineering Chongqing University of Arts and Science

Practical ***20 catalyzed reactions between indoles and a series of carbonyl compounds at room temperature are described, which afford bis（indolyl）methanes with isolated yields up to 96%,

关键词： Bis(indolyl)methanes BF3.Et2O lndoles Aldehydes Ketones

Evaluation of formaldehyde emission from particleboard using the large chamber and desiccator method at various loading ratios

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Journal of Forestry Research 2013年第1期24卷 137-142页

作者： QUE Ze-li WANG fei-bin MA ling-fei Furuno Takeshi Nanjing Forestry University Research Institute for Sustainable Humanosphere Kyoto University College of Wood Science and Technology Zhejiang A & F University Faculty of Science and Engineering Shimane University

We studied formaldehyde emission from uncoated particleboard with 16-mm thickness using the large chamber and the desiccator method. A chamber of 28.4 m3 was installed to simulate a mobile home. The formaldehyde off-gassing properties of particleboard were evaluated using the chamber. The relationship between the concentration obtained by the chamber and the values by the desiccator test was discussed in this study under different conditions of conditioning day, air exchange, and loading ratio. These two methods were compared and discussed regarding the formaldehyde emission level. Three loading ratios, 0.429 m2/m3, 0.264 m2/m3, and 0.132 m2/m3, were chosen to represent different applications of particleboard products. There was strong correlation between emissions and air exchange rates at equal product-loading ratios in the large chamber, the related coefficient R 2 exceeded 0.90. There was also an indication of a generic correlation between the large chamber and the two-hour desiccator test with a single product designated loading ratio, air exchange rate, and climatic conditions.

关键词： formaldehyde emission particleboard large chamber desiccator

Convergence of the Interior Penalty Integral Equation Domain Decomposition Method

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Journal of Electronic Science and Technology 2019年第2期17卷 152-160页

作者： Bo mi Yu Hu Zhang Liu ling Qin School of Information Science and Engineering Chongqing Jiaotong University Chongqing 400074 China College of Physics and Engineering Chengdu Normal University Chengdu 611130 China

To solve electrically large scattering problems with limited memory, a Gauss-Seidel iteration scheme is applied to solve the interior penalty integral equation domain decomposition method. Since the original stabilization parameter in this method is frequency-dependent, the convergence of stationary iterations shows obvious dependence on frequency and slow convergence can be observed in some frequency bands. To avoid this dependence and obtain fast convergence in a wide frequency band, a frequency-independent stabilization parameter is introduced. This parameter is chosen proportionally to the average mesh length and inversely proportionally to the wavelength. Numerical examples are proposed to verify the effectiveness of the proposed approach.

关键词： Domain decomposition electromagnetic scattering interior penalty perfect electrically conducting

Authentication scheme for industrial Internet of things based on DAG blockchain

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The Journal of China Universities of Posts and Telecommunications 2021年第6期28卷 1-12页

作者： Tang fei Dong Kun Ye Zhangtao ling Guowei College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Cyber Security and Information Law Chongqing University of Posts and TelecommunicationsChongqing 400065China

Internet of things(IoT) can provide the function of product traceability for industrial systems. Emerging blockchain technology can solve the problem that the current industrial Internet of things(IIoT) system lacks unified product data sharing services. Blockchain technology based on the directed acyclic graph(DAG) structure is more suitable for high concurrency environments. But due to its distributed architecture foundation, direct storage of product data will cause authentication problems in data management. In response, IIoT based on DAG blockchain is proposed in this paper, which can provide efficient data management for product data stored on DAG blockchain, and an authentication scheme suitable for this structure is given. The security of the scheme is based on a discrete-logarithm-based assumption put forth by Lysyanskaya, Rivest, Sahai and Wolf(LRSW) who also show that it holds for generic groups. The sequential aggregation signature scheme is more secure and efficient, and the new scheme is safe in theory and it is more efficient in engineering.

关键词： industrial Internet of things(IIoT) blockchain directed acyclic graph(DAG) aggregation signature

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Analysis of dipole-like ultra high frequency RFID tags close to metallic surfaces

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1217-1222页

作者： ling-fei MO Hong-jian ZHANG Hong-liang ZHOU State Key Lab of Industrial Control Technology Department of Control Zhejiang University Hangzhou 310027 China

It is a challenge for passive RFID tags to be mounted on the surface of metal because the parameters of tag antennas,such as the impedance matching,the radiation efficiency and the radiation pattern,are seriously affected by the metallic *** paper presents the characteristics of the dipole-like antennas of ultra high frequency(UHF) radio frequency identification(RFID) tags that are placed close to metallic *** finite element method(FEM) and method of moment(MoM) were used to simulate the changes of the antenna parameters near the metallic *** typical dipole-like antennas close to the metallic surface,a closed loop antenna and a loaded meander antenna,were modeled,and the performance was *** was carried out and the results were in good agreement with the simulation,showing that a distance of 0.05λ～0.1λ(λ is the free space wavelength) from the metallic surface could make the dipole-like UHF RFID tag performance be acceptable.

关键词： Radio frequency identification (RFID) Tag Metallic surface Finite element method (FEM) Method of moment (MoM)

Investigation on poly[(methylsilylene ethynylene phenylene ethynylene)-co-(tetramethyldisiloxane ethynylene phenylene ethynylene)]

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Chinese Chemical Letters 2010年第6期21卷 738-742页

作者： fei Gao ling ling Zhang Fa Rong Huang Lei Du Key Laboratory for Specially Functional Polymeric Materials and Related Technology of the ministry of Education East China University of Science and TechnologyShanghai 200237China

Poly[(methylsilylene ethynylene phenylene ethynylene)-co-(tetramethyldisiloxane ethynylene phenylene ethynylene)]was synthesized by polycondensation reaction of m-diethynylbenzene magnesium reagent with 1,3-dichlorotetramethyldisiloxane and *** copolymer was characterized by FT-IR,~1H NMR,differential scanning calorimetry and thermogravimetric *** results show that the copolymer exhibits good processability and cures at low *** cured copolymer shows high thermal stability.

关键词： Silicon-containing arylacetylene resin Siloxane m-Diethynylbenzene Methylsilylene

Blockage of ATPase-mediated energy supply inducing metabolic disturbances in algal cells under silver nanoparticles stress

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Journal of Environmental Sciences 2023年第9期131卷 141-150页

作者： Ruohua Qu mi Chen Jingfu Liu Qiting Xie Na Liu fei Ge Department of Environment College of Environment and ResourcesXiangtan UniversityXiangtan 411105China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adenosine triphosphate(ATP)generation of aquatic organisms is often subject to nanoparticles(NPs)stress,involving extensive reprogramming of gene expression and changes in enzyme activity accompanied by metabolic ***,little is known about the mechanism of energy supply by ATP to regulate the metabolism of aquatic organisms under NPs ***,we selected extensively existing silver nanoparticles(AgNPs)to investigate their implications on ATP generation and relevant metabolic pathways in alga(Chlorella vulgaris).Results showed that ATP content significantly decreased by 94.2%of the control(without AgNPs)in the algal cells at 0.20 mg/L AgNPs,which was mainly attributed to the reduction of chloroplast ATPase activity(81.4%)and the downregulation of ATPase-coding genes atpB and atpH(74.5%-82.8%)in *** dynamics simulations demonstrated that AgNPs competed with the binding sites of substrates adenosine diphosphate and inorganic phosphate by forming a stable complex with ATPase subunit beta,potentially resulting in the reduced binding efficiency of ***,metabolomics analysis proved that the ATP content positively correlated with the content of most differential metabolites such as D-talose,myo-inositol,and *** remarkably inhibited ATPinvolving metabolic pathways,including inositol phosphate metabolism,phosphatidylinositol signaling system,glycerophospholipid metabolism,aminoacyl-tRNA biosynthesis,and glutathione *** results could provide a deep understanding of energy supply in regulating metabolic disturbances under NPs stress.

关键词： Adenosine triphosphate Metabolomics Molecular dynamics simulations Nanoparticles Algae

IHVFL: a privacy-enhanced intention-hiding vertical federated learning framework for medical data

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Cybersecurity 2024年第2期7卷 96-112页

作者： fei Tang Shikai Liang Guowei ling Jinyong Shan College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsNo.2Chongwen RoadNan'an DistrictChongqing 400065China School of Cyber Security and Information Law Chongqing University of Posts and TelecommunicationsChongqing 400065China sudo Technology Co. LTD.Beijing 100083China

Vertical Federated Learning(VFL)has many applications in the field of smart healthcare with excellent ***,current VFL systems usually primarily focus on the privacy protection during model training,while the preparation of training data receives little *** real-world applications,like smart healthcare,the process of the training data preparation may involve some participant's intention which could be privacy information for this *** protect the privacy of the model training intention,we describe the idea of Intention-Hiding Vertical Feder-ated Learning(IHVFL)and illustrate a framework to achieve this privacy-preserving ***,we construct two secure screening protocols to enhance the privacy protection in feature ***,we implement the work of sample alignment bases on a novel private set intersection ***,we use the logistic regression algorithm to demonstrate the process of *** show that our model can perform better efficiency(less than 5min)and accuracy(97%)on Breast Cancer medical dataset while maintaining the intention-hiding goal.

关键词： Medical data Vertical federated learning Privacy-presserving Intention-hiding Logistic regression

Enhanced Mechanics in Injection Molded Isotactic Polypropylene/Polypropylene Random Copolymer Blends via Introducing Network-like Crystal Structure

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Chinese Journal of Polymer Science 2016年第2期34卷 164-173页

作者： Bi-qiang Jin Xin-peng Li ming Jin Da-shan mi fei-fei Wang Chao Xia 张杰 State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

The crystallization behavior, rheological behavior, mechanical properties and microstructures of injection molded isotactic polypropylene （iPP）, polypropylene random copolymer （co-PP） and iPP/co-PP blends were investigated. Differential scanning calorimetry （DSC） and dynamic rheological analysis illustrated that iPP and co-PP were compatible in the blends and co-PP uniformly dispersed in the/PP phase. Polarizing optical microscope （POM） was adopted to observe the crystal size and morphology evolution. The results of mechanical properties and scanning electron microscopy （SEM） indicated that the crystal size of iPP in iPP/co-PP blends （10 wt% co-PP ＋ 90 wt% iPP and 30 wt% co-PP ＋ 70 wt% iPP） radically decreased after the incorporation of co-PP. During crystallization, the molecular chain segments of co-PP could penetrate iPP spherulites and form a network-like crystalline structure. The network-like crystal structure could effectively transmit stress and consume more energy to overcome intermolecular forces to resist stretching. In this way, the strength would improve to a certain degree. The impact fracture mechanism of iPP/co-PP blends is quasi ductile fracture by multiple crazes. Our work discovered that the blends containing 10 wt% and 30 wt% ofco-PP exhibited prominent toughness and reinforcement.

关键词： Network-like Morphology Toughness Polypropylene random copolymer.