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MY WORK IN MOLECULAR SIEVE CHEMISTRY AND INORGANIC SYNTHE-SIS
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作者 Xu Ruren(Jilin University) 《Bulletin of the Chinese Academy of Sciences》 1995年第1期106-107,共2页
After my graduation as a chemistry major from Shanghai Jiaotong University in 1952. I was assigned to work at the People’s University of Northeast China (the predecessor of today’s Jilin University) in Changchun Cit... After my graduation as a chemistry major from Shanghai Jiaotong University in 1952. I was assigned to work at the People’s University of Northeast China (the predecessor of today’s Jilin University) in Changchun City, serving as a teaching assistant.I)uring my career on campus.I have lectured on a dozen courses on inorganic chemistry,general chemistry,analytic chemistry. rare-element chemistry, complex chemistry. inorganic synthesis,solid-state chemistry 展开更多
关键词 MY WORK IN MOLECULAR SIEVE CHEMISTRY AND INORGANIC synthe-sis HIGH
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Low side lobe pattern synthesis using projection method with genetic algorithm for truncated cone conformal phased arrays 被引量:7
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作者 Guoqi Zeng Siyin Li +1 位作者 Yan Zhang Shanwei L 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期554-559,共6页
A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone con... A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone conformal phased arrays are projected to the tangent plane in one generatrix of the truncated cone. Then two dimensional (2D) Chebyshev amplitude distribution optimization is respectively used in two mutual vertical directions of the tangent plane. According to the location of the elements, the excitation current amplitude distribution of each element on the conformal structure is derived reversely, then the excitation current amplitude is further optimized by using the genetic algorithm (GA). A truncated cone problem with 8x8 elements on it, and a 3D pattern desired side lobe level (SLL) up to 35 dB, is studied. By using the hybrid method, the optimal goal is accomplished with acceptable CPU time, which indicates that this hybrid method for the low sidelobe synthesis is feasible. 展开更多
关键词 conformal phased array low side lobe pattern synthe-sis projection method genetic algorithm optimization.
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Novel DDS Based OFDM Transmitter Structure without IFFT and Interpolation Filter 被引量:2
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作者 Sanjun Liu Guangming Gan 《China Communications》 SCIE CSCD 2021年第12期219-229,共11页
The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware... The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware resources and have long la-tency.To further meet the 5G and future 6G commu-nication requirements,this paper proposes a novel di-rect digital synthesis(DDS)based OFDM transmitter structure that can replace these modules.Due to the strong parallelism of the system structure,it is very suitable for implementation on field programable gate array(FPGA)platform.After making two special sim-plifications to the primary structure,the refined struc-ture becomes very simple compared with the tradi-tional structures.Most attractively,the proposed struc-ture has the following three advantages that i)the data transformation from frequency domain to time domain has zero latency,ii)the transformation length does not need to be an integer power of 2 and iii)the struc-ture does not even need to use any multiplier,thus leading to low implementation complexity and high speed.Comparative experiments are carried out on Intel FPGA platform which show that our DDS based structure can save more than half of the resources com-pared with the traditional structures and can provide the same bit error rate(BER)performance under the condition without using any LPSF. 展开更多
关键词 OFDM TRANSMITTER direct digital synthe-sis(DDS) fast Fourier transform(FFT)
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FLIGHT/THRUST INTEGRATED CONTROL USINGH∞SYNTHESIS IN AUTOMATIC CARRIER LANDING 被引量:2
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作者 YuYong YangYidong DaiShijun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第1期31-36,共6页
The landing task of an aircraft under low aerodynamic pressure on carrier requires precise airplane control,A flight/thrust integrated control system(FTICS)with constant ad,actual angle of attack,is developed using LM... The landing task of an aircraft under low aerodynamic pressure on carrier requires precise airplane control,A flight/thrust integrated control system(FTICS)with constant ad,actual angle of attack,is developed using LMI-based H∞synthesis.The typical single input/outputspecifications are translated into the weighting functions of an H∞output-feedback synthesis problem.The motiva-tion of the work is to improve the key performance of dy-namic tracking and air disturbance attenuation.The FTICS can keep the attitude andgle and the path angle un-changeable as the airplane is passing through the ramp at which the tracking radar doesnot work and the guidance signal is terminated.For engineering application,an or-der-reduction method of the H∞controller is also pro-posed,Simulational results indicate that the system satis-fies the design requirements quite well. 展开更多
关键词 flight/thrust integrated CONTROL H∞synthe-sis linear matrix INEQUALITY FLIGHT CONTROL system carrier-based aircraft 飞行控制 鲁棒控制 自动驾驶着陆系统 线性矩阵不等式 舰载飞机 推力控制 设计
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Microwave-Assisted Aqueous Synthesis: A Rapid Approach to Poly-functionalized Indoline-Spiro Benzofurodiazepines
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作者 王树良 程闯 +4 位作者 龚峰 吴飞跃 姜波 周建峰 屠树江 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2101-2108,共8页
New cycloaddition has been established for the synthesis of indoline-spiro benzofurodiazepine derivatives. Those reactions were conducted by reacting readily available and inexpensive starting materials, such as ben- ... New cycloaddition has been established for the synthesis of indoline-spiro benzofurodiazepine derivatives. Those reactions were conducted by reacting readily available and inexpensive starting materials, such as ben- zene- 1,2-diamines, tetronic acid and indoline-2,3-diones, in aqueous solution under microwave irradiation. When mono-substituted benzene-l,2-diamines as an amine component was employed, the reaction regioselectively re- sulted in the poly-functionalized indoline-spiro benzofurodiazepine with good yields. The present green synthesis shows attractive characteristics such as the use of water as reaction media, concise one-pot conditions, short reaction periods, easy work-up/purification and reduced waste production without the use of any strong acids or metal promoters. 展开更多
关键词 indoline-spiro benzofurodiazepine microwave chemistry multicomponent reactions aqueous synthe-sis
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