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Enhanced mid-to-near-infrared second harmonic generation in silicon plasmonic microring resonators with low pump power

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Photonics Research 2014年第5期2卷 143-149页

作者： jihua zhang Eric Cassan Xinliang zhang Wuhan National Laboratory for Optoelectonics&School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Institut d’Electronique Fondamentale UniversitéParis-SudOrsay 91405France e-mail:eric.cassan@u‑psud.fr

We propose an efficient and low-power second harmonic generation(SHG)process in a silicon-compatible hybrid plasmonic microring *** making the microring resonator doubly resonant at the fundamental wavelength of 3.1μm and second harmonic wavelength of 1.55μm,the SHG efficiency is enhanced by almost two orders of magnitude when compared to the previous result induced in a straight plasmonic waveguide.A SHG efficiency of 13.71%is predicted for a low pump power of 20 mW in a ring with radius of 2.325μ*** device provides a potential route for realizing efficient frequency conversion between mid-infrared and near-infrared wavebands on a chip.

关键词： pump resonator power

Recent Advances in C-F Bond Formation from Carbon-Centered Radicals

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Chinese Journal of Chemistry 2024年第9期42卷 1009-1031页

作者： jihua zhang Juanjuan Wang Qiang Cheng College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei 430072China

Construction of C-F bonds is a direct and efficient method for introducing fluorine into pharmaceuticals,agrochemicals,and *** such as nucleophilic,electrophilic,radical,and transition-metal catalyzed fluorination have been developed to meet the demand of diverse C-F bond *** them,radical fluorination has been witnessed with substantial advancement in a recent ***,we reviewed methods for formation of C-F bonds with carbon-centered radicals as key intermediates,especially in recent five *** introduce in the paper with different fluorinating reagents,strategies for radical generation,and application in late-stage functionalization and synthesis of PET *** also indicate the current limitations and propose the direction of the field for the future development.

关键词： Fluorine Fluorinating reagents Late-stage fluorination [^(18)F]jfluorination Radical reactions Synthetic methods

Fourier neural operator with boundary conditions for efficient prediction of steady airfoil flows

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 2019-2038页

作者： Yuanjun DAI Yiran AN Zhi LI jihua zhang Chao YU Department of Machanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Beijing Institute of Mechanical and Electrical Engineering Beijing 100074China

An efficient data-driven approach for predicting steady airfoil flows is proposed based on the Fourier neural operator(FNO),which is a new framework of neural *** reasons and experimental results are provided to support the necessity and effectiveness of the improvements made to the FNO,which involve using an additional branch neural operator to approximate the contribution of boundary conditions to steady *** proposed approach runs several orders of magnitude faster than the traditional numerical *** predictions for flows around airfoils and ellipses demonstrate the superior accuracy and impressive speed of this novel ***,the property of zero-shot super-resolution enables the proposed approach to overcome the limitations of predicting airfoil flows with Cartesian grids,thereby improving the accuracy in the near-wall *** is no doubt that the unprecedented speed and accuracy in forecasting steady airfoil flows have massive benefits for airfoil design and optimization.

关键词： deep learning(DL) Fourier neural operator(FNO) steady airfoil flow

Plastic zone analysis and support optimization of shallow roadway with weakly cemented soft strata

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International Journal of Mining Science and Technology 2015年第3期25卷 395-400页

作者： zhang jihua Wang Lianguo Li Qinghai Zhu Shuangshuang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology School of Mechanics & Civil Engineering China University of Ming and Technology College of Resources and Environmental Engineering Shandong University of Science and Technology

Based on a shallow roadway with weakly cemented soft strata in western China, this paper studies the range and degree of plastic zones in soft strata roadways with weak cementation. Geological radars were used to monitor the loose range and level of surrounding rocks. A mechanical model of weakly cemented roadway was established, including granular material based on the measured results. The model was then used to determine the plastic zone radium. The predicted results agree well with measured results which provide valuable theoretical references for the analysis of surrounding rock stability and support reinforcing design of weakly cemented roadways. Finally, a combined supporting scheme of whole section bolting and grouting was proposed based on the original supporting scheme. It is proved that this support plan can effectively control the deformation and plastic zone expansion of the roadway surrounding rock and thus ensure the long-term stable and safe mining.

关键词： Shallow coal seam Weakly cemented soft strata Granular material Geological radar Whole section bolting and grouting Combined supporting

Spatial Wavefunction Characterization of Femtosecond Pulses at Single-Photon Level

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Research 2020年第1期2020卷 341-348页

作者： Billy Lam Mohamed ElKabbash jihua zhang Chunlei Guo The Institute of Optics University of RochesterRochesterNew York 14627USA

Reading quantum information of single photons is commonly realized by quantum tomography or the direct(weak)measurement ***,these methods are time-consuming and face enormous challenges in characterizing single photons from an ultrafast light source due to the stringent temporal mode matching ***,we retrieve the spatial wavefunction of indistinguishable single photons from both a continuous wave source and a femtosecond light source using a self-referencing *** method only requires nine ensemble-averaged *** technique simplifies the measurement procedure of single-photon wavefunction and automatically mode matches each self-interfering single photon temporally,which enables the measurement of the spatial wavefunction of single photons from an ultrafast light source.

关键词： quantum consuming function

Improving Elasticity of Conductive Silicone Rubber by Hollow Carbon Black

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Chemical Research in Chinese Universities 2019年第6期35卷 1124-1132页

作者： zhang jihua CHEN Fengbo ZHAO Yunfeng LIU Mingjie Aerospace Research Institute of Material and Processing Technology Beijing 100076P.R.China Key Laboratory of Bio-inspired Smart Interfacial Science and Technology Ministry of EducationSchool of ChemistryBeihang UniversityBeijing 100191P.R.China

Carbon black-based conductive rubber composites have important impacts on electromagnetic interference(EMI)shielding ***,an excessive amount of carbon black in the recipes of these conductive rubbers has caused their weak ***,hollow carbon black(HCB)particles were used to tune the elasticity of conductive rubber *** hollow morphology produced a better compression recovery of HCB than other solid carbon black,such as acetylene *** the coupling agent was bonded to HCB,their conductive silicone rubber composites were featured by high stretching resilience,a fast compression recovery and excellent conductivity to satisfy the electromagnetic interference shielding ***,the rubber composites with coupling HCB had extremely low variations of mechanical property,conductivity and EMI shielding effectiveness after thermal accelerated aging *** is therefore revealed that the elasticity of HCB and its interfacial chemical coupling with rubber chains both play crucial roles in adjusting the elasticity of conductive rubber to sever long-term EMI protection.

关键词： Conductivity Carbon black Elasticity Electromagnetic shielding Sillicone rubber

Thermal Decomposition Kinetics and Mechanism ofLow-temperature Hydrogenated Acrylonitrile Butadiene Rubber Composites with Sodium Methacrylate

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Chemical Research in Chinese Universities 2016年第6期32卷 1045-1051页

作者： zhang jihua LI Jie LIU MinNie ZHAO Yunfeng WANG Shutao Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China Aerospace Research Institute of Material and Processing Technology Beijing 100076 P. R. China Key Laboratory of Bio-inspired Smart Interracial Science and Technology Ministry of Education School of Chemistry and Environment Beihang University Beifing 100191 P. R. China

Thermal decomposition processes and mechanism of low-temperature grade hydrogenated acrylonitrilebutadiene rubber（LTG-HNBR） composites with sodium methacrylate（NaMAA） were investigated by thermogravime-tric analysis（TGA） and Fourier transform infrared spectroscopy（FTIR） coupling technology in this article. The resultsof TGA demonstrate that the addition of NaMAA can enhance the thermal decomposition temperature of the ***, it was found that the composites spent more activation energies to decompose than pure rubber by thecalculations of multiply heating rate method. Time-resolved FTIR spectra show that NaMAA affects the initial de-composition of the composites. But in the following process, the composites maintained a similar behavior to the ma-trix. During the decomposition, PNaMAA nanostructures, in-situ generated by NaMAA, helped reduce the diffusionspeed of decomposition products and thus improved the thermal stability of the composites.

关键词： Decomposition kinetics Sodium methacrylate Hydrogenated acrylonitrile butadiene rubber composite

Advances in the understanding of inter-subspecific hybrid sterility and wide-compatibility in rice

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Chinese Science Bulletin 2009年第14期54卷 2332-2341页

作者： OUYANG YiDan CHEN JiongJiong DING jihua zhang QiFa National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan) Huazhong Agricultural University Wuhan 430070 China

Hybrid sterility is a major form of postzygotic reproductive isolation and frequently occurs in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa L.). It has been a major barrier for utilization of the strong heterosis expressed in hybrids between indica and japonica. A large number of loci for rice inter-subspecific hybrid sterility have been identified by genetic analysis. Cytological studies revealed that male and female gamete abortions and reduced affinity between the uniting gametes all occurred in indica-japonica hybrids, suggesting the complexity of the causes for inter-subspecific hybrid sterility. Two genes conditioning embryo-sac and pollen sterility respectively in indica-japonica hybrids have been cloned recently, providing opportunities for molecular characterization of the indica-japonica hybrid sterility and wide-compatibility. Future studies should aim at cloning more genes for indica-japonica hybrid sterility, characterizing the underlying molecular mechanism, and utilization of the findings for the development of inter-subspecific hybrids to increase rice productivity.

关键词：亚种间杂交水稻产量兼容性不育性种间杂交种杂种不育籼粳亚种杂交不育

Roadway layout for recycling residual coal pillar in room-and-pillar mining of thick coal seam

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International Journal of Mining Science and Technology 2015年第5期25卷 729-734页

作者： Jin Gan Wang Lianguo zhang jihua Hu Minjun Duan Ning State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221008 China School of Mechanics & Civil Engineering China University of Mining & Technology Xuzhou 221666 China

In the context of a room-and-pillar mining gob in Shanxi province in China,this paper numerically investigates the stress distribution and deformation rules of roadway surrounding rocks at various locations of residual coal pillars in room-and-pillar mining gobs using software FLAC3 *** is found that the concentrated stress beneath coal pillars distributes in a shape of ellipse.A reasonable roadway layout is then *** this design,it is indicated that roadways should be designed to avoid the supporting zones of pillars with increasing compression and take into account the roof falling and crushing in the upper *** to the surrounding rock deformation characteristics and mining roadway locations as well as the supporting principles of timely support,rock reinforcing,piecewise management and suiting local conditions,a new asymmetric shield supporting plan is *** field surveying results show that this supporting plan can effectively control the roadway rock deformation,thus guarantee the safe and smooth construction of roadways.

关键词： Room-and-pillar mine Residual coal pillar Repeated mining Roadway layout Asymmetric support