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| 1 | Preliminary assessment of the navigation and positioning performance of BeiDou regional navigation satellite system显示文摘BeiDou regional navigation satellite system(BDS)also called BeiDou-2 has been in full operation since December 27,2012.It consists of 14 satellites,including 5 satellites in Geostationary Orbit(GEO),5 satellites in Inclined Geosynchronous Orbit(IGSO),and 4 satellites in Medium Earth Orbit(MEO).In this paper,its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing,including satellite visibility,Position Dilution of Precision(PDOP)value,the precision of code and carrier phase measurements,the accuracy of single point positioning and differential positioning and ambiguity resolution(AR)performance,which are also compared with those of GPS.It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm,respectively,which are comparable to those of GPS,and the accuracy of BDS single point positioning has satisfied the design requirement.The real-time kinematic positioning is also feasible by BDS alone in the opening condition,since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS.The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km,which is on the same level with that of GPS.For the combined BDS and GPS,the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly.The accuracy of BDS/GPS carrier phase differential positioning is about 35 and 20%better than that of GPS for two short baseline tests in this study.The accuracy of BDS code differential positioning is better than 2.5 m.However it is worse than that of GPS,which may result from large code multipath errors of BDS GEO satellite measurements. | YANG YuanXi LI JinLong WANG AiBing XU JunYi HE HaiBo GUO HaiRong SHEN JunFei DAI Xian | 2014 | Science China Earth Sciences2014，57，1： | 125 |
| 2 | Brain-derived neurotrophic factor induces neuron-like cellular differentiation of mesenchymal stem cells derived from human umbilical cord blood cells in vitro显示文摘Human umbilical cord blood was collected from full-term deliveries scheduled for cesarean section.Mononuclear cells were isolated,amplified and induced as mesenchymal stem cells.Isolated mesenchymal stem cells tested positive for the marker CD29,CD44 and CD105 and negative for typical hematopoietic and endothelial markers.Following treatment with neural induction medium containing brain-derived neurotrophic factor for 7 days,the adherent cells exhibited neuron-like cellular morphology.Immunohistochemical staining and reverse transcription-PCR revealed that the induced mesenchymal stem cells expressed the markers for neuron-specific enolase and neurofilament.The results demonstrated that human umbilical cord blood-derived mesenchymal stem cells can differentiate into neuron-like cells induced by brain-derived neurotrophic factor in vitro. | Lei Chen Zhongguo Zhang Bing Chen Xiaozhi Liu Zhenlin Liu Hongliang Liu Gang Li Zhiguo Su Junfei Wang Guozhen Hui | 2011 | Neural Regeneration Research2011，6，13： | 8 |
| 3 | Development of ensemble learning models to evaluate the strength of coal-grout materials显示文摘In the loose and fractured coal seam with particularly low uniaxial compressive strength(UCS),driving a roadway is extremely difficult as roof falling and wall spalling occur frequently.To address this issue,the jet grouting(JG)technique(high-pressure grout mixed with coal particles)was first introduced in this study to improve the self-supporting ability of coal mass.To evaluate the strength of the jet-grouted coal-grout composite(JG composite),the UCS evolution patterns were analyzed by preparing 405 specimens combining the influential variables of grout types,curing time,and coal to grout(C/G)ratio.Furthermore,the relationships between UCS and these influencing variables were modeled using ensemble learning methods i.e.gradient boosted regression tree(GBRT)and random forest(RF)with their hyperparameters tuned by the particle swarm optimization(PSO).The results showed that the chemical grout composite has higher short-term strength,while the cement grout composite can achieve more stable strength in the long term.The PSO-GBRT and PSO-RF models can both achieve high prediction accuracy.Also,the variable importance analysis demonstrated that the grout type and curing time should be considered carefully.This study provides a robust intelligent model for predicting UCS of JG composites,which boosts JG design in the field. | Yuantian Sun Guichen Li Nong Zhang Qingliang Chang Jiahui Xu Junfei Zhang | 2021 | International Journal of Mining Science and Technology2021，31，2： | 6 |
| 4 | Insight into selective removal of copper from high-concentration nickel solutions with XPS and DFT:New technique to prepare 5N-nickel with chelating resin显示文摘An efficient and profitable separation process was proposed to prepare 5N(the purity of the metal solution reaches 99.999%) high-purity nickel from 3N nickel-solutions using Purolite S984. The adsorption performance of this superior resin, especially its selectivity for metal ions,was explored quantitatively. The maximum adsorption capacity for copper was 2.286 mmol/g calculated by the Langmuir model, which was twice as large as that for nickel. In the binary systems, the adsorption capacity for nickel was decreased by 45%, indicating direct competition for the active sites. The infinite separation factor for copper versus nickel exceeded 300, revealing the feasibility of preparing5N-level high-purity nickel solutions, which was further verified using the 800 BV(bed volume) effluent in the column dynamic process.According to the cost–benefit analysis, purification contributed to a profit of approximately 60,000 USD per cycle, and the investment return period was less than 1/3 years. Density functional theory analysis confirmed that four nitrogen atoms would be involved in the coordination complex and thus a structure involving two five-membered rings could be achieved. The X-ray photoelectron spectra confirmed the involvement of nitrogen atoms,implying a coordination ratio of approximately 1:1. | Xuewen Tao Fuqiang Liu Zhiping Bai Dongyang Wei Xiaopeng Zhang Junfei Wang Jie Gao Xiaowen Sun Baohua Li Chenghui Li Aimin Li | 2016 | Journal of Environmental Sciences2016，28，10： | 3 |
| 5 | Preparation of polystyrene spheres in different particle sizes and assembly of the PS colloidal crystals显示文摘Monodisperse polystyrene (PS) colloidal spheres were successfully prepared through emulsifier-free emulsion polymerization by controlling the polymerization reaction time, ionic strength of the system, concentration of the ionic copolymer (sodium p-styrenesulfonate) and other factors. The PS colloidal spheres were assembled into colloidal crystals whose structures were mainly face-centered cubic (fcc) close-packed. Then FDTD method was used to calculate the color-rendering characteristics of the colloidal crystals surface. The calculated results were consistent with the experimental results. | FANG JunFei, XUAN YiMin* & LI Qiang School of Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China | 2010 | Science China(Technological Sciences)2010，53，11： | 3 |
| 6 | Highly green fluorescent Nb2C MXene quantum dots for Cu2+ion sensing and cell imaging显示文摘Niobium carbide MXene quantum dots(Nb2 C MQDs)derived from 2 D Nb2 CTx(MXene)are the rising-star material recently.Herein,a sulfur and nitrogen co-doped Nb2 C MQDs(S,N-MQDs)were synthesized through a hydrothermal method.The obtained Nb2 C MQDs have excellent green fluorescence with a quantum yield(QY)of 17.25%.In addition,they exhibited excitatio n-dependent photoluminescence,antiphotobleaching and dispersion stability.They emit light at 520 nm when excited at 390 nm.The Nb2 C MQDs could be successfully applied to copper ion detection with detection limit of 2μmol/L and Caco-2 cells imaging. | Xiang Yan Junfei Ma Kaixuan Yu Jiapeng Li Lei Yang Jjiaqi Liu Juncheng Wang Lulu Cai | 2020 | Chinese Chemical Letters2020，31，12： | 3 |
| 7 | A Self-Organizing RBF Neural Network Based on Distance Concentration Immune Algorithm显示文摘Radial basis function neural network(RBFNN) is an effective algorithm in nonlinear system identification. How to properly adjust the structure and parameters of RBFNN is quite challenging. To solve this problem, a distance concentration immune algorithm(DCIA) is proposed to self-organize the structure and parameters of the RBFNN in this paper. First, the distance concentration algorithm, which increases the diversity of antibodies, is used to find the global optimal solution. Secondly,the information processing strength(IPS) algorithm is used to avoid the instability that is caused by the hidden layer with neurons split or deleted randomly. However, to improve the forecasting accuracy and reduce the computation time, a sample with the most frequent occurrence of maximum error is proposed to regulate the parameters of the new neuron. In addition, the convergence proof of a self-organizing RBF neural network based on distance concentration immune algorithm(DCIA-SORBFNN) is applied to guarantee the feasibility of algorithm. Finally, several nonlinear functions are used to validate the effectiveness of the algorithm. Experimental results show that the proposed DCIASORBFNN has achieved better nonlinear approximation ability than that of the art relevant competitors. | Junfei Qiao Fei Li Cuili Yang Wenjing Li Ke Gu | 2020 | IEEE/CAA Journal of Automatica Sinica2020，7，1： | 3 |
| 8 | Polyamines mediate the effect of post-anthesis soil drying on starch granule size distribution in wheat kernels显示文摘Polyamines(PAs) are important endogenous plant growth regulators responding to environmental stress and mediating many physiological processes including grain filling in cereals.This study investigated whether PAs mediate the effect of post-anthesis soil drying on starch granule size distribution,starch content,and weight of superior and inferior kernels of wheat(Triticum aestivum L.).Two wheat cultivars were grown in pots.Three treatments,well-watered(WW),moderate soil drying(MD) and severe soil drying(SD),were imposed from 9 days post-anthesis until maturity.PA levels in kernels and small,medium and large granules were measured.The results showed that superior kernels had much higher free spermidine(Spd) and free spermine(Spm) concentrations,larger volumes of medium starch granules,and smaller-sized large granules than did inferior kernels under all the treatments.Compared to WW,MD significantly increased the concentrations of free Spd and free Spm,activities of soluble starch synthase and granule-bound starch synthase,volume of medium granules,and starch content and kernel weight of inferior kernels,and decreased the size of large granules.SD produced the opposite effect.Application of Spd or Spm to spikes produced effects similar to those of MD,and application of an inhibitor of Spd and Spm synthesis produced effects similar to those of SD.These results suggest that PAs mediate the effect of post-anthesis soil drying on starch biosynthesis in wheat kernels by regulating key enzymes in starch synthesis and that elevated PA levels under MD increase the volume of medium granules and kernel weight of inferior kernels. | Yunji Xu Mengting Qiu Yinyin Li Xiyang Qian Junfei Gu Jianchang Yang | 2016 | The Crop Journal2016，4，6： | 2 |
| 9 | Electrochemical exfoliation of two-dimensional layered black phosphorus and applications显示文摘With the discovery of graphene,black phosphorus(BP)has been rediscovered as a two-dimensional(2 D)layered material.Since its first preparation in 2014,2 D BP has elicited immense interest,and has exhibited excellent properties,such as distinct pleated structures in layers,adjustable direct bandgap,high carrier mobility,moderate on/off ratio,large specific surface area,and various interesting in-layer anisotropies.However,the realization of these excellent properties depends on the preparation of highquality 2 D BP sheets.Electrochemical exfoliation methods are typically performed under mild conditions,thus,these methods are convenient,controllable,and can produce high-quality 2 D BP sheets.This review summarizes research progress in BP sheets preparation through anodic,cathodic,and electrolyte exfoliation in recent years.Different exfoliating methods affect the quality of 2 D BP sheets.Moreover,possible exfoliating mechanisms and the potential applications of different exfoliating methods are summarized and discussed in detail.Lastly,the shortcomings of existing research on electrochemical exfoliation are presented,and suggestions and prospects for future research on the electrochemical exfoliation of 2 D BP are proposed. | Le Li Dan Zhang Jianping Deng Yuchun Gou Junfei Fang | 2020 | Journal of Energy Chemistry2020，29，10： | 2 |
| 10 | Vision for energy material design:A roadmap for integrated data-driven modeling显示文摘The application scope and future development directions of machine learning models(supervised learning, transfer learning, and unsupervised learning) that have driven energy material design are discussed. | Zhilong Wang Yanqiang Han Junfei Cai An Chen Jinjin Li | 2022 | Journal of Energy Chemistry2022，31，8： | 2 |
| 11 | Enhanced Answer Selection in CQA Using Multi-Dimensional Features Combination显示文摘Community Question Answering(CQA) in web forums, as a classic forum for user communication,provides a large number of high-quality useful answers in comparison with traditional question answering.Development of methods to get good, honest answers according to user questions is a challenging task in natural language processing. Many answers are not associated with the actual problem or shift the subjects,and this usually occurs in relatively long answers. In this paper, we enhance answer selection in CQA using multidimensional feature combination and similarity order. We make full use of the information in answers to questions to determine the similarity between questions and answers, and use the text-based description of the answer to determine whether it is a reasonable one. Our work includes two subtasks:(a) classifying answers as good, bad, or potentially associated with a question, and(b) answering YES/NO based on a list of all answers to a question. The experimental results show that our approach is significantly more efficient than the baseline model, and its overall ranking is relatively high in comparison with that of other models. | Hongjie Fan Zhiyi Ma Hongqiang Li Dongsheng Wang Junfei Liu | 2019 | Tsinghua Science and Technology2019，24，3： | 2 |
| 12 | Preparation of three-dimensionally ordered macroporous perovskite materials显示文摘In this paper,we use La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 as examples to demonstrate a preparation method for threedimensionally ordered macroporous(3DOM) perovskite thermochromic materials.Polystyrene spheres with an average diameter of 220 nm were self-assembled into a three-dimensionally ordered colloidal crystal template.A mixed metal nitrate solution prepared using La(NO3) 3·6H2O,Ca(NO3) 2·4H2O,Sr(NO3) 2,Mn(CH3COO) 2·4H2O and an ethanol precursor was used to fill the interstitial voids of the polystyrene colloidal crystal templates.3DOM La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 materials were then obtained after the sphere templates were removed via drying and calcination.The results show that the framework of the 3DOM materials can have different thicknesses and pore shrinkage rates by varying the filling times.In addition,the Curie temperatures of the 3DOM and bulk La0.8Sr0.2MnO3 materials can be varied by altering the preparation method. | FANG JunFei XUAN YiMin LI Qiang | 2011 | Chinese Science Bulletin2011，56，20： | 2 |
| 13 | Structure Optimization for Echo State Network Based on Contribution显示文摘Echo State Network(ESN) is a recurrent neural network with a large, randomly generated recurrent part called the dynamic reservoir. Only the output weights are modified during training. However, proper balancing of the trade-off between the structure and performance for ESN remains a difficult task. In this paper, a structure optimized method for ESN based on contribution is proposed to simplify its network structure and improve its performance.First, we evaluate the contribution of reservoir neurons. Second, we present a pruning mechanism to remove the unimportant connection weights of reservoir neurons with low contribution. Finally, the new output weights are learned with the pseudo inverse method. The novel optimized ESN, named C-ESN, is tested on a Lorenz chaotic time-series prediction and an actual municipal sewage treatment system. The simulation results show that the C-ESN can have better prediction and generalization performance than ESN. | Dingyuan Li Fu Liu Junfei Qiao Rong Li | 2019 | Tsinghua Science and Technology2019，24，1： | 2 |
| 14 | Dynamic long-term microstructural and ultrastructural alterations in sensory nerves of rats of paclitaxel-induced neuropathic pain显示文摘 | Wu Yuan Li Jun Zhou Junfei Feng Yi | 2014 | Chinese Medical Journal2014，，16： | 2 |
| 15 | Curcumin delivery by methoxy polyethylene glycol-poly(caprolactone) nanoparticles inhibits the growth of C6 glioma cells显示文摘 | Junfei Shao Donghui Zheng Zhifeng Jiang Huae Xu Yong Hu Xiaolin Li Xiaowei Lu | 2011 | Acta Biochimica et Biophysica Sinica2011，43，4： | 2 |
| 16 | Gas phase polymerizationof 1 , 3-butadiene with supported neodymium-based catalyst :Investigation of molecular weight显示文摘 | Ni Xufeng Li Junfei Zhang Yifeng | 2004 | Journal of Applied PolymerScience2004，92，3： | 1 |
| 17 | An Algorithm to Detect the Presence of 3D Target Motion from ISAR Data显示文摘 | Junfei Li Hao Ling Victor Chen | 2003 | Multidimensional Systems and Signal Processing (-)2003，，1： | 1 |
| 18 | Deep Learning Accelerates the Discovery of Two- Dimensional Catalysts for Hydrogen Evolution Reaction显示文摘Two-dimensional materials with active sites are expected to replace platinum as large-scale hydrogen production catalysts.However,the rapid discovery of excellent two-dimensional hydrogen evolution reaction catalysts is seriously hindered due to the long experiment cycle and the huge cost of high-throughput calculations of adsorption energies.Considering that the traditional regression models cannot consider all the potential sites on the surface of catalysts,we use a deep learning method with crystal graph convolutional neural networks to accelerate the discovery of high-performance two-dimensional hydrogen evolution reaction catalysts from two-dimensional materials database,with the prediction accuracy as high as 95.2%.The proposed method considers all active sites,screens out 38 high performance catalysts from 6,531 two-dimensional materials,predicts their adsorption energies at different active sites,and determines the potential strongest adsorption sites.The prediction accuracy of the two-dimensional hydrogen evolution reaction catalysts screening strategy proposed in this work is at the density-functional-theory level,but the prediction speed is 10.19 years ahead of the high-throughput screening,demonstrating the capability of crystal graph convolutional neural networks-deep learning method for efficiently discovering high-performance new structures over a wide catalytic materials space. | Sicheng Wu Zhilong Wang Haikuo Zhang Junfei Cai Jinjin Li | 2023 | Energy & Environmental Materials2023，6，1： | 1 |
| 19 | Paper-based blood typing device that reports patient's blood type 'in writing'显示文摘 | LI Miaosi TIAN Junfei AI-TAMIMI M | 2012 | Angewandte Chemie International Edition2012，51，22： | 1 |
| 20 | Numerical Analysis of Energy Effect in Laser-TIG Hybrid Welding显示文摘The hybrid source that combined CO2 laser with TIG arc to proceed welding was analyzed. Based on an energymodel, the temperature field and weld shape were calculated numerically. The heat transfer characteristic of thehybrid heat source to workpiece and its effect to weld shape were also analyzed. Through analyzing the enhancementeffect of the hybrid heat source, the absorption effect and defocusing effect of the hybrid arc to laser were calculated,and the regularity of the energy density to the current was obtained subsequently. At last, the critical energy matchesto induce the enhancement effect of CO2 laser-TIG arc hybrid welding were obtained. | Yanbin CHEN Liqun LI Junfei FANG Xiaosong FENG | 2003 | Journal of Materials Science & Technology2003，19，z1： | 1 |
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