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Chinese Chemical Letters 2014年第8期25卷 1169-1173页

作者： Dong-Qing Xu zhong-Wen pan Center of Analysis and Measurement Anhui Science and Technology University School of Chemistry and Chemical Engineering Anhui University

A highly effective phase transfer of a quaternary ammonium gemini surfactant with ester groups（（diethylhexanedioate） diyl-a,v-bis（dimethyl dodecyl ammonium bromide） referred to as 12-10-12）was synthesized with high yield and characterized by infrared spectroscopy, elemental analysis and1 HNMR. Then, 12-10-12 was used as a phase transfer catalyst to study the catalytic effect on the reaction of anhydrous sodium acetate and 4-methylbenzyl chloride. The possible catalytic mechanism and the influence of surfactant concentration, temperature and type are also discussed. The experimental results showed that the catalysis efficiency was more active than the traditional, single-chained surfactant,tetrabutyl ammonium bromide. It also revealed that the reaction was first-order with respect to the concentration of 4-methylbenzyl chloride. The concentration of 4-methylbenzyl chloride grew linearly with the concentration of 12-10-12 and as the reaction temperature increased. The optimum reaction time was 7 h.

关键词： Gemini surfactant Phase-transfer catalyst Kinetic model

Spatial modulation search applied to the search and confirmation of highly scintillated pulsars at FAST with a pulsar discovered in M3

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Research in Astronomy and Astrophysics 2021年第8期21卷 1-4页

作者： Lei Qian zhi-Chen pan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

We present a pulsar candidate identification and confirmation procedure based on a position-switch mode during the pulsar search *** method enables the simultaneous search and confirmation of a pulsar in a single observation,by utilizing the different spatial features of a pulsar signal and radio frequency interference(RFI).Based on this method,we performed test pulsar search observations in globular clusters M3,M15 and *** discovered and confirmed a new pulsar,M3 F,and detected the known pulsars M3 B,M15 A to G(except C) and M92 A.

关键词： (stars:)pulsars:general methods:observational methods:data analysis

Postoperative morbidity adversely impacts oncological prognosis after curative resection for hilar cholangiocarcinoma

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World Journal of Gastroenterology 2022年第9期28卷 948-960页

作者： zhi-Peng Liu Wei-Yue Chen Yan-Qi Zhang Yan Jiang Jie Bai Yu pan Shi-Yun zhong Yun-Ping zhong zhi-Yu Chen Hai-Su Dai Department of Hepatobiliary Surgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Department of Clinical Center of Oncology Lishui Hospital of Zhejiang UniversityLishui 323000Zhejiang ProvinceChina Department of Health Statistics Third Military Medical University(Army Medical University)Chongqing 400038China

BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is *** To evaluate the influence of postoperative morbidity on tumor recurrence and mortality after curative resection for *** Patients with recently diagnosed HCCA who had undergone curative resection between January 2010 and December 2017 at The First Affiliated Hospital of Army Medical University in China were *** independent risk factors for morbidity in the 30 d after surgery were investigated,and links between postoperative morbidity and patient characteristics and outcomes were *** morbidities were divided into five grades based on the Clavien-Dindo classification,and major morbidities were defined as Clavien-Dindo≥*** and multivariate Cox regression analyses were used to evaluate the risk factors for recurrence-free survival(RFS)and overall survival(OS).RESULTS Postoperative morbidity occurred in 146 out of 239 patients(61.1%).Multivariate logistic regression revealed that cirrhosis, intraoperative blood loss > 500 mL, diabetes mellitus,and obesity were independent risk factors. Postoperative morbidity was associated with decreasedOS and RFS (OS: 18.0 mo vs 31.0 mo, respectively, P = 0.003;RFS: 16.0 mo vs 26.0 mo, respectively,P = 0.002). Multivariate Cox regression analysis indicated that postoperative morbidity wasindependently associated with decreased OS [hazard ratios (HR): 1.557, 95% confidence interval(CI): 1.119-2.167, P = 0.009] and RFS (HR: 1.535, 95%CI: 1.117-2.108, P = 0.008). Moreover, majormorbidity was independently associated with decreased OS (HR: 2.175;95%CI: 1.470-3.216, P <0.001) and RFS (HR: 2.054;95%CI: 1.400-3.014, P < 0.001) after curative resection for *** morbidity (especially major morbidity) may be an independent risk factor forunfavorable prognosis in HCCA patients following curative resection

关键词： Hilar cholangiocarcinoma Morbidity Surgery Oncology Survival Recurrence

Recent Development of Quantum Dot Deposition in Quantum Dot-Sensitized Solar Cells

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Transactions of Tianjin University 2022年第5期28卷 374-384页

作者： Ziwei Li Zhenxiao pan Xinhua zhong Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and EnergySouth China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

As new-generation solar cells,quantum dot-sensitized solar cells(QDSCs)have the outstanding advantages of low cost and high theoretical efficiency;thus,such cells receive extensive research *** power conversion efficiency(PCE)has increased from 5%to over 15%in the past ***,compared with the theoretical efficiency(44%),the PCE of QDSCs still needs further *** low loading amount of quantum dots(QDs)is a key factor limiting the improvement of cell *** loading amount of QDs on the surface of the substrate film is important for the performance of QDSCs,which directly affects the light-harvesting ability of the device and interfacial charge *** optimization of QD deposition and the improvement of the loading amount are important driving forces for the rapid development of QDSCs in recent years and a key breakthrough in future *** this paper,the research progress of QD deposition on the surface of substrate films in QDSCs was *** addition,the main deposition methods and their advantages and disadvantages were discussed,and future research on the further increase in loading amount was proposed.

关键词： Quantum dot-sensitized solar cells Quantum dot deposition Capping ligand-induced self-assembly Secondary deposition

A rate-dependent constitutive model for saturated frozen soil considering local breakage mechanism

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2458-2474页

作者： pan Wang Enlong Liu Bin zhi Bingtang Song School of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an710054China Northwest Institute of Eco-Environment and Resources State Key Laboratory of Frozen Soil EngineeringChinese Academy of SciencesLanzhou730000China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China

A rate-dependent constitutive model for saturated frozen soil is vital in frozen soil mechanics,especially when simultaneously describing the nonlinearity,dilatancy and strain-softening *** distribution of the non-uniform strain rate of saturated frozen soil at the meso-scale due to the local icecementation breakage is described by a newly binary-medium-based homogenization *** on the field-equation-based approach of the meso-mechanics theory,the interaction expression of the strain rate at macro-and meso-scale is derived,which can give the strain rate concentration tensor at different crushed *** the thermodynamics and empirical assumption,a breakage ratio in the rate-dependent form is *** overcomes the limitations of the existing binary-medium-based models that are difficult to simulate rate-dependent mechanical *** on these assumptions,a newly binary-medium-based rate-dependent model is proposed considering both the ice bond breakage and material composition characteristics of saturated frozen *** proposed constitutive model has been validated by the test results on frozen soils with different temperatures and strain rates.

关键词： Binary-medium-based model Rate-dependency Frozen soil Grain debonding effect Multi-scale constitutive model

Structure and Dynamics of Energy Materials from Machine Learning Simulations:A Topical Review

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Chinese Journal of Chemistry 2021年第11期39卷 3144-3154页

作者： Shu-Hui Guan Cheng Shang zhi-pan Liu Shanghai Academy of Agricultural Sciences Shanghai201403 China Collaborative Innovation Center of Chemistry for Energy Material Shanghai Key Laboratory of molecular Catalysis and Innovative MaterialsKey Laboratory of Computational Physical ScienceDepartment of ChemistryFudan UniversityShanghai200438 China

Energy materials featuring the capability to store and release chemical energy reversibly involve generally complex geometrical structures with multiple *** has been a great challenge to establish the quantitative relationship between the structure of materials and their dynamic physicochemical *** recent years,machine learning(ML)technique has demonstrated its great power in accelerating the research on energy *** topical review introduces the key ingredients and typical applications of ML to energy *** mainly focus on the ML based atomic simulation via ML potentials in different architectures/implementations,including high dimensional neural networks(HDNN),Gaussian approximation potential(GAP),moment tensor potentials(MTP)and stochastic surface walking global optimization with global neural network potential(SSW-NN)*** cases studies,namely,Si,LiC and LiTiO systems,are presented to demonstrate the ability of ML simulation in assessing the thermodynamics and kinetics of complex material *** highlight that the SSW-NN method provides an automated solution for global potential energy surface data collection,ML potential construction and ML simulation,which boosts the current ability for large-scale atomic simulation and thus holds the great promise for fast property evaluation and material discovery.

关键词： Machine learning Materials science Atomic simulation Thermodynamics Kinetics

Weakly supervised action anticipation without object annotations

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Frontiers of Computer Science 2023年第2期17卷 101-110页

作者： Yi zhong Jia-Hui pan Haoxin LI Wei-Shi ZHENG School of Computer Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Machine Intelligence and Advanced Computing Ministry of EducationGuangzhou 510006China

Anticipating future actions without observing any partial videos of future actions plays an important role in action prediction and is also a challenging *** obtain abundant information for action anticipation,some methods integrate multimodal contexts,including scene object ***,extensively labelling each frame in video datasets requires considerable *** this paper,we develop a weakly supervised method that integrates global motion and local finegrained features from current action videos to predict next action label without the need for specific scene context ***,we extract diverse types of local features with weakly supervised learning,including object appearance and human pose representations without ground ***,we construct a graph convolutional network for exploiting the inherent relationships of humans and objects under present *** evaluate the proposed model on two datasets,the MPII-Cooking dataset and the EPIC-Kitchens dataset,and we demonstrate the generalizability and effectiveness of our approach for action anticipation.

关键词： action anticipation weakly supervised learning relation modelling graph convolutional network

Using shapes correlation for active contour segmentation of uterine fibroid ultrasound images in computer-aided therapy

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 37-52页

作者： NI Bo HE Fa-zhi pan Yi-teng YUAN zhi-yong School of Computer Science Wuhan University School of Computer Science Hubei Polytechnic University

Segmenting the lesion regions from the ultrasound （US） images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound （HIFU）, as a popular computer-aided therapy, has been widely used in the treatment of uterine fibroids. However, such segmentation in HIFU remains challenge for two reasons：（1） the blurry or missing boundaries of lesion regions in the HIFU images and （2） the deformation of uterine fibroids caused by the patient＇s breathing or an external force during the US imaging process, which can lead to complex shapes of lesion regions. These factors have prevented classical active contour-based segmentation methods from yielding desired results for uterine fibroids in US images. In this paper, a novel active contour-based segmentation method is proposed, which utilizes the correlation information of target shapes among a sequence of images as prior knowledge to aid the existing active contour method. This prior knowledge can be interpreted as a unsupervised clustering of shapes prior modeling. Meanwhile, it is also proved that the shapes correlation has the low-rank property in a linear space, and the theory of matrix recovery is used as an effective tool to impose the proposed prior on an existing active contour model. Finally, an accurate method is developed to solve the proposed model by using the Augmented Lagrange Multiplier （ALM）. Experimental results from both synthetic and clinical uterine fibroids US image sequences demonstrate that the proposed method can consistently improve the performance of active contour models and increase the robustness against missing or misleading boundaries, and can greatly improve the efficiency of HIFU therapy.

关键词： Active contour shapes correlation ultrasound image segmentation matrix recovery computer-aided therapy.

Ordered cone-structured tin directly grown on carbon paper as efficient electrocatalyst for CO_(2) electrochemical reduction to formate

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Journal of Energy Chemistry 2021年第4期30卷 236-243页

作者： Hexiang zhong Yanling Qiu Xianfeng Li Liwei pan Huamin Zhang College of Environmental and Chemical Engineering Dalian UniversityDalian 116622LiaoningChina Division of Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

The conversion of carbon dioxide to chemicals by the electrochemical reactions(ERC)is an efficient solution to the current energy crisis and excess CO_(2) *** is still a great challenge and of significance to synthesize a highly selective,efficient,and non-noble metal electrocatalyst that facilitates the ERC reaction.A novel triton X-100(C_(14)H_(22)O(C_(2)H_(4)O)n)assisted electrodeposition method was developed to synthesize the ordered cone-structured tin(OCSn)electrocatalysts with controllable morphology and *** results suggest that Triton X-100 plays an important role in directing the structure of the Sn electrocatalysts during the electrodeposition *** OCSn synthesized at 60 m A cm^(-2) achieves the best *** selectively catalyzes the ERC on the onset potential about 110 m V lower than Sn synthesized without Triton *** 0.5 M Na HCO_(3),high faradaic efficiency(92%)for formate product on OCSn has been *** prominently,the catalyst presents excellent stability,showing no performance deterioration during 30 h *** work provides an efficient,green,and scalable synthesis method of the electrocatalyst for CO_(2) reduction to formate.

关键词： CO_(2)electrochemical reduction CO2 emission reduction Ordered cone-structure tin(OCSn) Electro-deposition

Pseudo-dynamic tests on masonry residential buildings seismically retrofitted by precast steel reinforced concrete walls

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 587-597页

作者： Li Wenfeng Wang Tao Chen Xi zhong Xiang pan Peng Beijing Institute of Architectural Design Beijing 100045 China Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration Sanhe 065201 China Department of Civil Engineering Tsinghua University Beijing 100084 China

A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.

关键词： masonry buildings precast SRC panel seismic retrofit pseudo-dynamic test seismic performance