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microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science China Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2 & YIN Yingwu2,3 1. College of Chemistry & Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China 2. TH-UNIS Insight Co., Ltd., Beijing 100085, China 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China College of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2 h at 200℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Theoretical and experimental researches on C-band three-cavity transit-time effect oscillator

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Science China(Physics,Mechanics & Astronomy) 2004年第3期47卷 310-329页

作者： FAN Zhikai1, LIU Qingxiang1, CHEN Daibing1, TAN Jie1 & ZHOU Haijing2 1. Institute of Applied Electronics, Chinese Academy of Engineering Physics, Mianyang 621900, China 2. Institute of Applied Physics and Computational Mathematics, Beijing 100088, China Institute of Applied Electronics Chinese Academy of Engineering Physics Mianyang China Institute of Applied Physics and Computational Mathematics Beijing China

The C-band three-cavity transit-time effect oscillator (3C TTTO) is a novel high power microwave device based on the transit-time effect of the three-cavity (3C) resonator. The operational principle of this device is briefly expounded in this paper, and the theoretical and experimental researches on the radial insulation diode, the 3C resonator, the double-gap output cavity and the circular waveguide bevel cut radiation antenna are presented in detail. By using the analytic method, the eigen modes and their field distributions of the 3C resonator are developed, and some basic laws of the transit-time effect are obtained in non-p mode field of the 3C resonator. At last, the experimental results are given. This device generated RF peak power in excess of 400MW with 15ns FWHM, and its beam-wave power conversion efficiency is about 17%.

关键词： C-band, three-cavity (3C) resonator, transit-time effect, high power microwave, oscillator.

Research and Practice in Green Chemical Technologies

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合成化学 2004年第Z1期12卷 125-125页

作者： Yin Yingwu Dept. of Chemistry Tsinghua University TH-UNIS Insight Co. Ltd

Green chemistry is also called environment harmless or environment friendly *** chemistry requires to use new synthetic methods, engineering technologies and processes to eliminate or reduce by-products, wastes or products that harmful to human health, community safety,and ecology environment. Green chemistry pursues to control the usage of the harmful and toxic materials, reduce waste emission, avoid necessity to treat the wastes; Green Chemistry advocates wastes management from the beginning, improving the efficiency of atoms, optimizing the use of resources and energy, lowering the cost of production. Green Chemistry technologies are the ultimate path to the clean chemical production in the *** Co. takes 'hospital of enterprises' and 'bank of technologies' as our characteristics in business, and deems the development and spread of green chemistry as our mission. We developed an unique business model which combines education, research and production. In the past 8 years,we had applied and obtained more than 30 patents and received more than ten national and provincial awards in technology *** had made great progress in the manufacturing of organophosphorus pesticides, especially the production of omethoate, methamidophos, paraquat and glycyrrhizinic phosphor, etc., which made a stable foundation for INSIGHT's development. We had also achieved great success in the high efficiency low toxic pesticides, such as imidacloprid, etofenprox, metalaxyl and in the new synthetic methods in various amino acids as well as in the pharmaceutical intermediates. The new method of preparation indigo using N-phenylglycinonitrile is an advanced process in the world in terms of the clean production technology for Ferro cyanide and HCN's transformation rate improvement. We solved the pollution problem of the old route. The newly developed substituted product for indigo using a clean production technology which greatly reduced the material consumption and

关键词： Green Chemistry Technology, microwave, origin of life, organic electrochemistry,light-curing technology, dimethyl ether