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Chinese Journal of Polymer Science 2019年第8期37卷 834-840页

作者： Jing Li Shao-Hua Jin guan-chao lan Zi-Shuai Xu Lu-Ting Wang Na Wang Li-Jie Li School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China Research Institute of Gansu Yin guang Chemical Industry Group Co.Ltd Baiyin 730900 China

To effectively improve the performance and expand the applications of polymers, molecular dynamics(MD) simulations with the COMPASS force field have been applied to predict the miscibility, glass transition temperature(Tg), and mechanical properties of poly(vinyl chloride)/dioctyl phthalate(PVC/DOP) blends. The solubility parameter values obtained are in good agreement with the reference data and the little difference(|Δδ|< 2.0 MPa0.5) between two components indicates that PVC/DOP is a miscible system. Tg is predicted by the slope of the free volume and density versus temperature simulation data based on density and free volume theory which is agree well with the experimental data. In addition, the analyses of mechanical properties results indicate that the values of Young’s modulus(E), bulk modulus(K), and shear modulus(G) decrease with the addition of DOP, demonstrating that the rigidity of material is weakened and the ductility is improved. The mechanical properties can also be effectively improved by increasing the temperature, which may provide a more flexible mixture, with lower E, K, G but an increased ductility.

关键词： Poly(vinyl chloride)(PVC) Dioctyl phthalate (DOP) MD simulations Glass transition temperature Mechanical properties

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen guan Cailing Chen chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst Electrocatalysis

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng Bo Shao chao-Min Xu Ke Wang Jia-Zhu Wen Li-Kang Luo Jia-Cheng guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report

Flutter and gust response analysis of a wing model including geometric nonlinearities based on a modified structural ROM

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Chinese Journal of Aeronautics 2020年第1期33卷 48-63页

作者： chao AN chao YANG Changchuan XIE lan YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

In this paper,a framework is established for nonlinear flutter and gust response analyses based on an efficient Reduced Order Model(ROM).The proposed method can be used to solve the aeroelastic response problems of wings containing geometric nonlinearities.A structural modeling approach presented herein describes the stiffness nonlinearities with a modal *** orthogonal spanwise modes describe the foreshortening effects of the *** linearization of the ROM under nonlinear equilibrium states is applied to a nonlinear flutter analysis,and the fully nonlinear ROM coupled with the non-planar Unsteady Vortex Lattice Method(UVLM)is applied to gust response ***,extended Precise Integration Method(PIM)ensures accuracy of the dynamic equation *** demonstrate applicability and accuracy of the method presented,a wind tunnel test is conducted and good agreements between theoretical and test results of nonlinear flutter speed and gust response deflection are *** method described in this paper is suitable for predicting the nonlinear flutter speed and calculating the gust responses of a large-aspect-ratio wing in time ***,the results derived highlight the effects of geometric nonlinearities obviously.

关键词： Aeroelasticity Flutter Geometric nonlinearity Reduced order models Response analysis Structural model

Hydrophilic interaction liquid chromatography with indirect ultraviolet detection for the separation and quantification of pyrrolidinium ionic liquid cations

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Chinese Chemical Letters 2015年第11期26卷 1371-1375页

作者： chao guan Hong Yu College of Chemistry and Chemical Engineering Harbin Normal University

A method of hydrophilic interaction liquid chromatography with indirect ultraviolet detection was developed to determine three pyrrolidinium ionic liquid cations, i.e. N-methyl-N-ethyl pyrrolidinium cation （[MEPy]＋）, N-methyl-N-propyl pyrrolidinium cation （[MPPy]＋） and N-methyl-N-butyl pyrrolidi- nium cation （[MBPy]＋）. Chromatographic separation was achieved on a hydrophilic column using imidazolium ionic liquids and organic solvents as the mobile phase. The effects of the background ultraviolet absorption reagents, the imidazolium ionic liquids, detection wavelength, organic solvents, column temperature and the pH value of the mobile phase on the separation and determination of pyrrolidinium cations were investigated and the retention behaviors in hydrophilic interaction chromatography were discussed. The optimized chromatographic conditions were selected. Under the optimal conditions, the detection limits （SIN = 3） for [MEPy]＋, [MPPy]＋ and [MBPy]＋ were 0.59, 0.53 and 0.46 mg/L, respectively. The method has been successfully applied to the determination of the three ionic liquids synthesized in our chemistry laboratory. This research results may improve the analytical method of ionic liauid cations.

关键词： Hydrophilic interaction liquidchromatographyIndirect ultraviolet detectionPyrrolidinium cationsIonic liquids

Arbitrary Decode-Forward Relaying with Re-Encoded Bits Selection Strategy for Polar Codes

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China Communications 2023年第8期20卷 153-162页

作者： Di guan Kai Niu chao Dong Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we propose an arbitrary decode-forward single-relay scheme for finite blocklength polar codes,which can be applied to the general symmetric discrete memoryless relay channel with orthogonal receiver *** relay node decodes the received *** relay node selectively re-encodes the message and transmits it to the destination ***,in order to minimize the upper-bound of the block error probability,we propose a selection strategy to decide the proper re-encoded bit set by the *** results are presented to illustrate the improvement in decoding performance of the proposed scheme compared to conventional relay schemes in both additive white Gaussian noise(AWGN)channel and Rayleigh fading channel(RFC).

关键词： polar codes decode-and-forward relaying arbitrary relay channel block error rate estimation

Direct Conversion of Methane to Propylene

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Research 2024年第2期2023卷 463-472页

作者： Yunpeng Hou Yuxiang lan chao Qian Shaodong Zhou College of Chemical and Biological Engineering Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyZhejiang University310027 HangzhouP.R.China Zhejiang Provincial Innovation Center of Advanced Chemicals Technology Institute of Zhejiang University-Quzhou324000 QuzhouP.R.China

Nonoxidative coupling of methane exhibits promising prospect in that it affords value-added hydrocarbons and hydrogen with high atom ***,challenge remains in direct,selective conversion of methane to more valuable hydrocarbons like *** current work presents a catalyst with well-dispersed Ta atoms anchored by graphitic C_(3)N_(4)-supported *** a catalyst is able to convert methane selectively to ethylene and propylene at a relatively low temperature(350℃).The conception of the active center and construction of the catalyst have been described,and the origins of the catalytic performance are discussed.

关键词： methane catalyst hydrocarbons

Automatic Colorization with Improved Spatial Coherence and Boundary Localization

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Journal of Computer Science & Technology 2017年第3期32卷 494-506页

作者： Wei Zhang chao-Wei Fang guan-Bin Li Department of Computer Science The University of Hong Kong Hong Kong China School of Data and Computer Science Sun Yat-sen University Guangzhou 510006 China

Grayscale image colorization is an important computer graphics problem with a variety of applications. Recent fully automatic colorization methods have made impressive progress by formulating image colorization as a pixel-wise prediction task and utilizing deep convolutional neural networks. Though tremendous improvements have been made, the result of automatic colorization is still far from perfect. Specifically, there still exist common pitfalls in maintaining color consistency in homogeneous regions as well as precisely distinguishing colors near region boundaries. To tackle these problems, we propose a novel fully automatic colorization pipeline which involves a boundary-guided CRF （conditional random field） and a CNN-based color transform as post-processing steps. In addition, as there usually exist multiple plausible colorization proposals for a single image, automatic evaluation for different colorization methods remains a challenging task. We further introduce two novel automatic evaluation schemes to efficiently assess colorization quality in terms of spatial coherence and localization. Comprehensive experiments demonstrate great quality improvement in results of our proposed colorization method under multiple evaluation metrics.

关键词： automatic colorization deep learning conditional random field (CRF) color transform quality evaluation

A Symbol Timing Recovery Algorithm of M-PSK Signals for Burst Modem Applications with Small Packet Size

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China Communications 2016年第6期13卷 138-146页

作者： Yu Chi lan Chen chao Lv Institute of Microelectronics Chinese Academy of Sciences

Feedforward symbol timing recovery techniques are particularly important for initial acquisition in burst modems. However, these techniques either have large calculation burden or sensitive to frequency offsets. In this paper, we proposed an efficient symbol timing recovery algorithm of MPSK signals named OMQ(Ordered Maximum power using Quadratic approximation partially) algorithm which is based on the Quadratic Approximation(QA) algorithm. We used ordered statistic sorting method to reduce the computational complexity further, meanwhile maximum mean power principle was used to decrease frequency offset sensitivity. The proposed algorithm adopts estimation-down sampling structure which is suitable for small packet size transmission. The results show that, while comparing with the QA algorithm, the computational complexity is reduced by 75% at most when 8 samples per symbol are used. The proposed algorithm shows better performance in terms of the jitter variance and sensitivity to frequency offsets.

关键词： symbol timing maximum mean power ordered statistic Quadratic Approximation

Model for the Whole Roller Leveling Process of Plates with Random Curvature Distribution Based on the Curvature Integration Method

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 145-155页

作者： Ben guan chao Zhang Yong Zang Yuan Wang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with the leveling process of plates with a random curvature distribution. On the other hand, the current models are suitable only for stable leveling processes and ignore the biting in and tailing out stages. This study presents a new plate-leveling model based on the curvature integration method, which can describe the leveling process of plates with random curvature distribution. Further, the model is solved in two cases in order to take the biting in and tailing out stages into consideration. The proposed model is evaluated by comparing with a plate leveling experiment. Finally, the leveling process of a plate with a wave bent is studied using the proposed model. It is found that the contact angles vary greatly during the biting in and tailing out stages. However, they are relatively steady during the 5 roller leveling stage. In addition, the contact angle of roller No. 2 is the smallest, which is close to 0. Roller leveling can effectively eliminate bending in the plate, but there are regions in the head and tail of the plate, where roller leveling is not effective. The non-leveling region length is about 2 times that of the roller space. This study proposes a quasi-static plate-leveling model, which makes it possible to analyze the dynamic straightening process using a curvature integration method. It also makes it possible to analyze the straightening process of a plate with random curvature distribution.

关键词： Leveling Curvature integration method Curvature Contact angle Deflection