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Chinese Journal of Chemistry 2018年第11期36卷 1011-1016页

作者： Zheng-yang gu Rong zhang Shun-yi Wang Shun-Jun Ji Key Laboratory of Organic Synthesis of jiangsu Province College of Chemistry Chemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou Jiangsu 215123 China

A Co(II)‐catalyzed effective synthesis of amidinium imine derivatives from the reaction of isocyanides and boric acids using organic azides as nitrene source has been developed. This protocol provides a new, environment‐friendly and simple strategy to construct amidinium imine derivatives with a range of substrates without any oxidants and additives.

关键词： Co(II)‐catalysis isocyanide boric acids azides nitrene radical C1 building blocks

Treatment and hydraulic performances of the NiiMi process for landscape water

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 132-142页

作者： jian yang Liang-bo zhang yi-fan WU Ya-yi WANG Cui LI Wen LIU State Key Laboratory of Pollution Control and Resources Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

This paper describes the NiiMi process designed to treat landscape water. The main aim of the research was to investigate the feasibility of NiiMi for removing organic and nutriment materials from landscape water. During the batch-scale NiiMi operation, the removal rates of color ranged from 66.7%o-80% , of turbidity from 31.7%-89.3%o, of chemical oxygen demand （COD） from 7%-36.5%, of total phosphor （TP） from 43%-84.2%, of soluble phosphate from 42.9%-100%, of total nitrogen （TN） from 4.2%-46.7%, and of NH4^＋-N from 39.3%-100% at the hydraulic loading of 0.2 m^3/（m^2·d）. Results showed that the removal efficiencies of COD, TP, soluble phosphate and TN decreased with the decline in the temperature. The NiiMi process had a strong shock loading ability for the removal of the organics, turbidity, TP, soluble phosphate, TN and NH4^＋-N. Three sodium chloride tracer studies were conducted, labeled as TS 1, TS2, and TS3, respectively. The mean hydraulic retention times （mean HRTs） were 31 h and 28 h for TSI and TS2, respectively, indicating the occurrence of a dead zone volume of 12% and 20% for TS 1 and TS2, respectively. TS 1 and TS2 displayed the occurrence of short-circuiting in the NiiMi system. The comparison results between TS1 and TS2 were further confirmed in the values obtained for some indicators, such as volumetric efficiency （e）, short-circuiting （S）, hydraulic efficiency （2） and number of continuously stirred tank reactors （N）.

关键词： NiiMi system Landscape water Purification efficiency Hydraulic efficiency Tracers

Effect of Al on Expansion Behavior of Mg–Al Alloys During Solidification

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Acta Metallurgica Sinica(English Letters) 2019年第5期32卷 559-565页

作者： yi Meng jian Sun Lei-Gang Cao Yue yang Hai-Tao zhang jian-Zhong Cui School of Mechanical and Materials Engineering North China University of Technology Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University

The cooling curves and the change of contraction/expansion during solidification and cooling were tested by using a selfmade device which could achieve the one-dimensional contraction instead of three-dimensional contraction of the ***, the effects of Al content(0, 1.1, 3, 5, 10, 12.9, 15, 17, 19, 22, 24 and 30 wt%) on the thermal contraction/expansion of the binary Mg-Al as-cast alloys during solidification were obtained. The results showed that expanding instead of contraction was present in Mg-Al alloys with the addition of 0-30 wt% Al during solidification. The values of expansion significantly increased at first and then decreased with the increase in Al content. And the maximum expansion ratio of 0.44%(maximum expansion value: 0.841 mm) was present in the Mg-15 wt% Al alloy. Contraction instead of expansion occurred once the temperature drops to the temperature corresponding to the expansion value in total, indicating the occurrence of a continuous expansion during the solidification process in mushy zone for the Mg alloys with Al addition of 5-30 wt%. The expansion value in total consisted of two parts: the expansions occurring in the liquid-phase zone and mushy zone. The expansion in liquid zone was present in every Mg-Al alloy, and it contributed to the most proportion of the total expansion value when the Al content in Mg-Al alloy was lower than 10 wt% or higher than 22 wt%. However, the total expansion value was mainly determined by the solidification behavior in mushy zone when the Al content was among 10-22 wt% in Mg-Al alloys.

关键词： Solidification Mg alloys Al content Expansion

Growth Mechanism of Vertically Aligned Carbon Nanotube Arrays

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Ji-cheng zhang Yong-jian Tang Yong yi Min-jie Zhou Kang-fu Ma Wei-dong Wu Chao-yang Wang Science and Technology on Plasma Physics Laboratory Research Center of Laser Fusion China Academy of Engineering Physics Mianyang 621900 China College of Material Science and Engineering Southwest University of Science and TechnologyMianyang 621010 China

Vertically aligned multi-walled carbon nanotube arrays grown on quartz substrate are obtained by co-pyrolysis of xylene and ferrocene at 850 °C in a tube *** spectroscopy and high resolution transmission electron microscopymeasurements show that the single-walled carbon nanotubes are only present on top of vertically aligned multi-walled carbon nanotube arrays. It has been revealed that isolated single-walled carbon nanotubes are only present in those floating catalyst generated materials. It thus suggests that the single-walled carbon nanotubes here are also generated by floating catalyst. Vertically aligned carbon nanotube arrays on the quartz substrate have shown good orientation and good graphitization. Meanwhile, to investigate the growth mechanism, two bi-layers carbon nanotube films with different thickness have been synthesized and analyzed by Raman spectroscopy. The results show that the two-layer vertically aligned carbon nanotube filmsgrow “bottom-up”. There are distinguished Raman scattering signals for the second layer itself, surface of the first layer, interface between the first and second layer, side wall and bottom surface. It indicates that the obtained carbon nanotubes follow the base-growth mechanism, and the single-walled carbon nanotubesgrow from their base at the growth beginning when iron catalyst particles have small size. Those carbon nanotubes with few walls (typically <5 walls) have similar properties, which also agree with the base-growth mechanism.

关键词： Single-walled carbon nanotubes Multi-walled carbon nanotubes Growth mechanism Microstructure characterization

Bearing-only Visual SLAM for Small Unmanned Aerial Vehicles in GPS-denied Environments

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International Journal of Automation and computing 2013年第5期10卷 387-396页

作者： Chao-Lei Wang Tian-Miao Wang jian-Hong Liang yi-cheng zhang yi Zhou Robotics Institute Beijing University of Aeronautics and Astronautics

This paper presents a hierarchical simultaneous localization and mapping（SLAM） system for a small unmanned aerial vehicle（UAV） using the output of an inertial measurement unit（IMU） and the bearing-only observations from an onboard monocular camera.A homography based approach is used to calculate the motion of the vehicle in 6 degrees of freedom by image feature *** visual measurement is fused with the inertial outputs by an indirect extended Kalman filter（EKF） for attitude and velocity ***,another EKF is employed to estimate the position of the vehicle and the locations of the features in the *** simulations and experiments are carried out to test the performance of the proposed *** result of the comparison with the referential global positioning system/inertial navigation system（GPS/INS） navigation indicates that the proposed SLAM can provide reliable and stable state estimation for small UAVs in GPS-denied environments.

关键词： Visual simultaneous localization and mapping(SLAM) bearing-only observation inertial measurement unit small unmanned aerial vehicles(UAVs) GPS-denied environment

Product Specification Analysis for Modular Product Design Using Big Sales data

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 19-33页

作者： jian zhang Bingbing Li Qingjin Peng Peihua gu Department of Mechanical Engineering Shantou UniversityShantou515063China Department of Mechanical Engineering University of ManitobaManitobaR3T 5V6Canada International Institute for Innovative Design and Intelligent Manufacturing of Tianjin University Shaoxing312000China School of Mechanical Engineering Tianjin UniversityTianjin300350China

Big data on product sales are an emerging resource for supporting modular product design to meet diversified customers’requirements of product specification *** better facilitate decision-making of modular product design,correlations among specifications and components originated from customers’conscious and subconscious preferences can be investigated by using big data on product *** study proposes a framework and the associated methods for supporting modular product design decisions based on correlation analysis of product specifications and components using big sales *** correlations of the product specifications are determined by analyzing the collected product sales *** building the relations between the product components and specifications,a matrix for measuring the correlation among product components is formed for component *** rules for supporting the decision making of modular product design are proposed based on the frequency analysis of the specification values per component cluster.A case study of electric vehicles illustrates the application of the proposed method.

关键词： Modular product design Customer preference Product specifications Correlation analysis Big sales data Electric vehicle

Tunable chiroptical application by encapsulating achiral lanthanide complexes into chiral MOF thin films

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Nano Research 2022年第2期15卷 1102-1108页

作者： Rui Zhai yihong Xiao Zhigang gu jian zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Chiral metal-organic frameworks(chirMOFs)have been widely considered on enantioselective adsorption/separation,asymmetric catalysis,biological and nonlinear optical ***,chirMOFs are facing a great challenge in development of chiroptical thin films with circularly polarized luminescence(CPL)***,we first report CPL thin films by encapsulating achiral lanthanide complexes Ln(acac)_(3)(Ln=Eu_(a)Tb_(b)Gd_(c))into the pores of surface-coordinated chirMOF thin films(SURchirMOF)[Zn_(2)(cam)_(2)dabco]_(n) with layer by layer(Ibl)encapsulation *** to the unique combination of chiral porous MOF and adjustable luminescent complexes in the host-guest thin films,the obtained Ln(acac)_(3)@SURchirMOF possess strong and tunable CPL property with high dissymmetry *** compared CPL and fluorescent lifetime results show that the advantage of this preparation strategy can effectively achieve energy transfer from Ln(acac)_(3) to SURchirMOF,resulting in an excellent CPL *** study not only provides a novel strategy to develop new types of chiral thin films but also offers an efficient approach for tunable chiroptical applications.

关键词： metal-organic frameworks lanthanide complexes thin films encapsulation chiral optical application

Conditional survival probability of distant-metastatic hepatocellular carcinoma: A population-based study

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World Journal of Gastrointestinal Oncology 2023年第11期15卷 1874-1890页

作者： Yong-Ping yang cheng-Jun guo Zhao-Xuan gu Jun-Jie Hua Jia-Xuan zhang jian Shi Department of General Surgery The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina

BACKGROUND The prognosis of many patients with distant metastatic hepatocellular carcinoma(HCC)improved after they survived for several *** with tradi-tional survival analysis,conditional survival(CS)which takes into account changes in survival risk could be used to describe dynamic survival *** To evaluate CS of distant metastatic HCC *** Patients diagnosed with distant metastatic HCC between 2010 and 2015 were extracted from the Surveillance,Epidemiology and End Results *** and multivariate Cox regression analysis were used to identify factors for overall survival(OS),while competing risk model was used to identify risk factors for cancer-specific survival(CSS).Six-month CS was used to calculate the probability of survival for an additional 6 mo at a specific time after initial diagnosis,and standardized difference(d)was used to evaluate the survival differences between *** were constructed to predict ***α-fetoprotein expression,higher T stage(T3 and T4),N1 stage,non-primary site surgery,non-chemotherapy,non-radiotherapy,and lung metastasis were independent risk factors for actual OS and CSS through univariate and multivariate *** survival rates decreased over time,while CS rates gradually *** for the 6-month CS,the survival difference caused by chemotherapy and radiotherapy gradually disappeared over time,and the survival difference caused by lung metastasis ***,the influence of age and gender on survival gradually *** were fitted for patients who have lived for 2,4 and 6 mo to predict 6-month conditional OS and CSS,*** area under the curve(AUC)of nomograms for conditional OS decreased as time passed,and the AUC for conditional CSS gradually *** CS for distant metastatic HCC patients substantially increased over *** dynamic risk factors,nomograms constructed at a specific time could predict more accur

关键词： Conditional survival Hepatocellular carcinoma Distant metastasis Prognosis Nomogram

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Chinese Physics Letters 1998年第9期15卷 677-679页

作者： ZHAO yi-guang cheng Lei HUANG Xian-ling zhang guo-yi LI Jing yang Zhi-jian Department of Physics Peking UniversityBeijing 100871 National Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871

Using solid-phase regrowth technique,Pd/Ge contact has been made on the GaN layer,and very good ohmic behavior was observed for the *** Photoluminescence(PL)spectra for different structures formed by the Pd/Ge contact,GaN layer,sapphire substrate,and mirror were studied,and a defect-assisted transition was found at 450nm related to Ge *** results show that the microcavity effect strongly influences the PL spectra of the band-gap and defect-assisted transitions.

关键词： GaN sapphire ohmic

Thermal Conductivity of Diamond-Based Silicon-on-Insulator Structures

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Chinese Physics Letters 1996年第8期13卷 610-612页

作者： gu Chang-zhi JIN Zeng-sun LU Xiang-yi ZOU guang-tian LU jian-xia YAO da zhang Ji-fa FANG Rong-chuan State key Laboratory of Superhard Materials Jilin UniversityChangchun 130023 Institute of Northeast Microelectron Shenyang 110032 Department of Physics University of Science and Technology of ChinaHefei 230026

Diamond films of various thickness(1-300μm)were deposited on single-crystal Si active(300μm)by a microwave plasma chemical vapor deposition method using gaseous mixtures of methane and *** thinning of the Si layer by machine and ion-beam polishing a diamond-based silicon-on-insulator structure with final Si layer thickness of about 1μm is *** conductivity of this structure material with various thicknesses of diamond and Si layer was *** with bulk silicon,the thermal conductivity of the siliconon-diamond structure with 300μm diamond and 1μm silicon increases by 850%.

关键词： Diamond conductivity structure