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Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li hao-ran Shen Shao-Juan Wang hao Zhang Jian Hu Rui Xin Xiao-Li Sun Shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

A reduction scheme of PAPR in CO-OFDM system using time-delay neural networks

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Optoelectronics letters 2025年

作者： TONG Zhengrong LIU Zhihong WANG hao ZHANG Weihua ZHANG Tianhao JIA Qiqi Tianjin Key Laboratory of Thin Film Electronics and Communication Devices， Engineering Research Center for Optoelectronic Devices and Communication Technology of the Ministry of Education， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

An iterative partial transmission sequence （IPTS） cascading time-delay neural network （TDNN） scheme is proposed to reduce peak-to-average power ratio （PAPR） in the coherent optical orthogonal frequency division multiplexing （CO-OFDM） systems. The IPTS algorithm further reduces computational complexity based on the partial transmission sequence （PTS） algorithm. TDNN is trained by the iterative clipping filtering （ICF） method. Simulation results show that the proposed scheme achieves a PAPR reduction of 5.84 dB when complementary cumulative distribution function （CCDF） is 10-4and an extra transmission distance of 200 km for 10-3bit error rate （BER） compared to the original signals.

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A Network Pharmacology-Based Study on Antidepressant Effect of Salicornia europaea *** with Experimental Support in Chronic Unpredictable Mild Stress Model Mice

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Chinese Journal of Integrative Medicine 2022年第4期28卷 339-348页

作者： SUN Dan-chen WANG ran-ran XU hao ZHU Xue-hui SUN Yan QIAO Shi-qing QIAO Wei Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of PharmacyTianjin Medical UniversityTianjin300070China

Objective:To investigate the pharmacodynamic material basis,mechanism of actions and targeted diseases of Salicornia europaea L.(SE)based on the network pharmacology method,and to verify the antidepressant-like effect of the SE extract by pharmacological ***:Retrieval tools including Chinese medicine(CM),PubMed,PharmMapper,MAS 3.0 and Cytoscape were used to search the components of SE,predict its targets and related therapeutic diseases,and construct the"Component-TargetPathway"network of SE for central nervous system(CNS)***,protein-protein interaction(PPI)network,Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO)function annotation of depression-related targets were analyzed to predict the antidepressant mechanism of *** unpredictable mild stress(CUMS)model was used to construct a mouse model with depression-like *** the animals were randomly divided into 6 groups(n=10)including the normal group(nonstressed mice administered with distilled water),the CUMS group(CUMS mice administered with distilled water),the venlafaxine group(CUMS mice administered with venlafaxine 9.38 mg/kg),SE high-,medium-,and low-dose groups(CUMS mice administered with SE 1.8,1.35 and 0.9 g/kg,respectively).Then some relevant indicators were determined for experimental verification by the forced swim test(FST),the tail suspension test(TST)and open-field test(OFT).Dopamine(DA)concentration in hippocampus and cerebral cortex,IL-2 and corticosterone(CORT)levels in blood,and nuclear factor E2 related factor 2(Nrf2),kelch-like epichlorohydrin related protein 1(Keap1),NAD(P)H dehydrogenase[quinone]1(NQO1)and heme oxygenase-1(HO-1)levels in mice were measured by enzyme linked immunosorbent assay(ELISA)and Western blot respectively to explore the possible ***:The"target-disease"network diagram predicted by network pharmacology,showed that the potential target of SE involves a variety of CNS diseases,among which depression ac

关键词： Salicornia europaea L. network pharmacology tail suspension test forced swim test depression

Stability of Decoherence-Free Subspaces under Stochastic Phase Fluctuations

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Communications in Theoretical Physics 2006年第3X期46卷 447-452页

作者： ZENG hao-Sheng NIE Jian-Jun KUANG le-Man Department of Physics Hunan Normal University Changsha 410081 China

We study the stability of decoherence-free subspaces under stochastic phase fluctuations by analytically and numerically evaluating the fidelity of the corresponding decoherence-free subspace bases with stochastic phase fluctuations under the evolution of environment. The environment is modeled by a bath of oscillators with infinite degrees of freedom and the register-bath coupling is chosen to be a general dissipation-decoherence form. It is found that the decoherence-free subspaces take on good stability in the case of small dissipation and small phase fluctuations.

关键词： decoherence-free subspaces stochastic phase fluctuations

Temperature-insensitive micro-displacement sensor with spindle-shaped structure single mode fiber

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Optoelectronics letters 2025年

作者： ZHANG Weihua MU Jinlin WANG hao WANG Dong YU haozheng TAO Yipeng Engineering Research Center of Optoelectronic Devices and Communication Technology，Ministry of Education， Tianjin Key Laboratory of Film Electronic and Communication Devices， School of Integrated Circuit Science and Engineering， Tianjin University of Technology Engineering Infrastructure Department，Autonomous Driving Department Xiaomi EV Company Ltd

A temperature-insensitive micro-displacement sensor based on a spindle-shaped single mode fiber (SMF) is presented and demonstrated. The SMF is bent into a balloon-shaped SMF and burned into a spindle-shaped SMF by a flame. Due to the bending of the fiber， part of the incident light leaks from the fiber core into the fiber cladding， which excites higher order cladding modes. Therefore， modal interference occurs. The experimental results show that the maximum sensitivity of the sensors is -203 pm/μm when micro-displacement varies from 0 to 80 μm. The sensors are insensitive to temperature in the range of 20-70℃. In addition， the sensors have the advantages of simple structure， low cost， small volume， high sensitivity and stability， which can be widely used in numerous high-precision industrial measurements and civil engineering structure monitoring fields.

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Anti-noise performance of the pulse coupled neural network applied in discrimination of neutron and gamma-ray

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Nuclear Science and Techniques 2022年第6期33卷 89-101页

作者： hao-ran Liu Zhuo Zuo Peng Li Bing-Qi Liu Lan Chang Yu-Cheng Yan State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China The Engineering and Technical College of Chengdu University of Technology Leshan 614000China Southwestern Institute of Physics Chengdu 610225China Chengdu University Chengdu 610106China

In this study,the anti-noise performance of a pulse-coupled neural network(PCNN)was investigated in the neutron and gamma-ray(n-γ)discrimination *** experiments were conducted in two *** the first group,radiation pulse signals were pre-processed using a Fourier filter to reduce the original noise in the signals,whereas in the second group,the original noise was left untouched to simulate an extremely high-noise *** each part,artificial Gaussian noise with different intensity levels was added to the signals prior to the discrimination *** the aforementioned conditions,the performance of the PCNN was evaluated and compared with five other commonly used methods of n-γdiscrimination:(1)zero crossing,(2)charge comparison,(3)vector projection,(4)falling edge percentage slope,and(5)frequency gradient *** experimental results showed that the PCNN method significantly outperforms other methods with outstanding FoM-value at all noise ***,the fluctuations in FoM-value of PCNN were significantly better than those obtained via other methods at most noise levels and only slightly worse than those obtained via the charge comparison and zerocrossing methods under extreme noise ***,the changing patterns and fluctuations of the FoMvalue were evaluated under different noise ***,based on the results,the parameter selection strategy of the PCNN was *** conclusion,the PCNN method is suitable for use in high-noise application scenarios for n-γdiscrimination because of its stability and remarkable discrimination *** does not rely on strict parameter settings and can realize satisfactory performance over a wide parameter range.

关键词： Pulse coupled neural network Zero crossing Frequency gradient analysis Vector projection Charge comparison Neutron and gamma-ray discrimination Pulse shape discrimination

Modified k-ω model using kinematic vorticity for corner separation in compressor cascades

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Science China(Technological Sciences) 2016年第5期59卷 795-806页

作者： LIU YangWei YAN hao FANG le LULiPeng LI QiuShi Shao Liang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University Beijing 100191 China Collaborative Innovation Center of Advanced Aero-Engine Beihang University Beijing 100191 China Laboratory of Mathematics and Physics Ecole Centrale de Pekin Beihang University Beijing 100191 China Laboratoire de Mecanique ties Fluides et d'Acoustique Ecole Centrale de Lyon Ecullv 69134 France

A new method of modifying the conventional k-w turbulence model for comer separation is proposed in this paper. The production term in the w equation is modified using kinematic vorticity considering fluid rotation and deformation in complex geometric boundary conditions. The corner separation flow in linear compressor cascades is calculated using the original k-w model, the modified k-w model and the Reynolds stress model （RSM）. The numerical results of the modified model are compared with the available experimental data, as well as the corresponding results of the original k-w model and RSM. In terms of accuracy, the modified model, which significantly improves the performance of the original k-w model for predicting comer separation, is quite competitive with the RSM. However, the modified model, which has considerably lower computational cost is more robust than the RSM.

关键词： k-w comodel kinematic vorticity corner separation compressor cascades

Cultural Factors and Study Destinations of International Students

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China & World Economy 2019年第6期27卷 26-49页

作者： hao Wei ran Yuan Laixun Zhao Business School Beijing Normal UniversityChina Research Institute for Economics&Business Kobe UniversityJapan

In this paper,we examine the role of cultural factors in attracting international students using data of 102 countries and regions from 2000 to *** results show that the export of cultural products is conducive to the increase in international *** students choose to study in developing countries with an official language and religious beliefs that are different from their home country,but tend to choose developed countries with a common *** also analyze the features of inbound and outbound international students specific to *** study indicates that''soft power,"such as a unique culture,common values and migration networks,is important for attracting foreign students.

关键词： Chinese students abroad cultural factor cultural goods export international student migration network

Automatic identification and feature recognition of the metro-led underground space in China based on point of interest data

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Underground Space 2023年第2期9卷 186-199页

作者： Yun-hao Dong Fang-le Peng Yang Du Yan-Qing Men Research Center for Underground Space and Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Jinan Rail Transit Group Co. LTD.JinanShandong 250101China

Metro-led underground space(MUS)plays a crucial role in modern underground space *** studies have shown its great potential for high-quality urban ***,limited evidence about MUS was available on a national scale,resulting in incomplete and unsystematic knowledge of MUS *** interaction relationship between MUS and the surrounding built environment also remains *** fill the research gap,an automatic method for MUS identification and development features extraction was proposed based on point of interest *** applied the method to identify the MUS in 28 Chinese cities and estimated the development status of MUS in China for the first *** nationwide statistics of MUS and correlation analysis of development features were *** show that complex MUS(CMUS)share is significantly lower than that of simple ***,CMUS development in China is primarily dominated by public transport and does not have a solid functional link to its *** comparative analysis of MUS development in four primary urban agglomerations was also conducted,and their development char-acteristics were *** study aims to expand the planning toolkit and construct the MUS database,which sheds light on the data-driven planning for MUS.

关键词： Development features Metro-led underground space Point of interest