光化学反应是以光为激发手段，研究激发态分子的反应，是洁净、节能、节约的合成方法，它为有机合成化学提供了新方法，是当前合成化学中非常活跃的研究领域之一。 近期，《中国科学：化学》编辑部邀请有机光化学领域专家、华中师范大学化学学院 肖文精 教授作为特约编辑，为英文刊 SCIENCE CHINA Chemistry 组织出版了 ” Organic Photochemistry ” 专题，发表在 2016 年第 59 卷第 2 期。 Preface: special topic on organic photochemistry Wen-JingXiao SCIENCE CHINA Chemistry , 2016, 59 (2): 159-160. DOI :10.1007/s11426-016-5558-3 The cycloaddition reaction using visible light photoredox catalysis SCIENCE CHINA Chemistry , 2016, 59 (2): 161-170. DOI :10.1007/s11426-015-5516-5 C-H allylation of N-aryl-tetrahydroisoquinolines by merging photoredox catalysis with iodide catalysis SCIENCE CHINA Chemistry, 2016, 59 (2): 171-174. DOI : 10.1007/s11426-015-5548-x Visible light catalyzed aromatization of 1,3,5-triaryl-2-pyrazolines by platinum(II) polypyridyl complex under oxidant-free condition SCIENCE CHINA Chemistry , 2016, 59 (2): 175-179. DOI : 10.1007/s11426-016-5554-7 Photoredox-catalyzed annulation of cyclobutylanilines with alkenes, alkynes, and diynes in continuous flow SCIENCE CHINA Chemistry , 2016, 59 (2): 180-183. DOI : 10.1007/s11426-015-5547-y Redox-triggered hydroarylation of o -(hydroxyalkyl)arylalkynes with arylsulfonyl chlorides using visible light catalysis SCIENCE CHINA Chemistry , 2016, 59 (2): 184-189. DOI : 10.1007/s11426-015-5529-0 Regioselective synthesis of α-bromo-α,β-unsaturated carbonyl compounds via photocatalytic α-bromination reactions SCIENCE CHINA Chemistry , 2016, 59 (2): 190-194. DOI : 10.1007/s11426-015-5530-7 Visible-light-promoted and photocatalyst-free trifluoromethylationof enamides SCIENCE CHINA Chemistry , 2016, 59 (2): 195-198. DOI : 10.1007/s11426-015-5528-1 Synthesis of aziridines by visible-light induced decarboxylative cyclization of N -aryl glycines and diazo compounds SCIENCE CHINA Chemistry , 2016, 59 (2): 199-202. DOI : 10.1007/s11426-015-5513-8 敬请关注该专题: http://chem.scichina.com:8081/sciBe/EN/volumn/volumn_7206.shtml
This ClimateWire story was sent to you by: cliu.info@gmail.com Personal message: Dear Prof. Jiang -- Thanks again for your kind support. Please see the organic farming story below. Looking forward to learn your new studies on climate change issue in the future. All the best, Coco AN EE PUBLISHING SERVICE AGRICULTURE: Organic farming will help China cut emissions without compromising crop production -- study Coco Liu, EE Asia correspondent Published: Monday, May 11, 2015 HONG KONG -- Agriculture is known as a major contributor to greenhouse gas emissions, but a new study finds that organic farming can reverse the agriculture ecosystem from a carbon source to a carbon sink. In a paper published in Science Bulletin , a group of scientists estimated that more than 1 billion tons of excess carbon dioxide can be stored in China's farmlands annually through regenerative organic farming, ranching and land use. Meanwhile, crop yields can also increase as the soil fertility is improved by the use of organic manure. To mitigate greenhouse gas emissions and retain soil fertility, organic agriculture might be a wise choice for decreasing the intensive use of synthetic fertilizers, protecting environments, and further improving crop yields, the scientists said. They demonstrated how to do so by integrating organic farming with cattle breeding in a rural area of eastern China's Shandong province. The majority of nutrient inputs in farmlands there traditionally came from chemical fertilizer. During the experimental run, the scientists fed cattle with crop residues, collected and composted cattle manure, and used it to replace chemical fertilizer for crop production. The study's finding shows that although cattle breeding causes higher emissions of methane and other type of greenhouse gases, the new practice still sequesters more carbon, thanks to crop residue recycling and chemical reduction. Putting that into numbers, the study notes, farmlands using cattle manure absorb greenhouse gas emissions equivalent to 8.8 tons of carbon dioxide per hectare every year. By contrast, the farmland using chemical fertilizer releases greenhouse gas emissions equivalent to 2.7 tons of carbon dioxide. Besides that, turning crop residues into animal feed helps make full use of agricultural waste. According to the scientists' estimation, China produces about 630 million tons of crop residues annually, with more than two-thirds of them being abandoned or burned -- causing air pollution and driving up greenhouse gas emissions. World's biggest agricultural emitter has options Unlike ranchers in Brazil who have cleared forests to build facilities for cattle, most farmers in eastern China enclose part of their existing agricultural land as cattle pasture. As a result, emissions from land-use change are barely a concern there. A 2011 report from the Food and Agriculture Organization of the United Nations says that agriculture causes about one-third of global greenhouse gas emissions when direct energy use; emissions from livestock; the production of fertilizers, pesticides, machinery and equipment; as well as soil degradation and land-use change for feed production are taken into account. An analysis by the Washington, D.C.-based think tank World Resources Institute shows that in 2011, China generated more agriculture-related emissions than any other nation. Jiang Gaoming, one of the study's authors and a professor at the Chinese Academy of Sciences' Institute of Botany, said that using organic manure can significantly reduce greenhouse gas emissions from crop production. If the country completely replaces chemical fertilizer with organic manure, the potential should be 1.38 billion tons of carbon dioxide for the whole China's farmland per year, Jiang said. However, there are barriers to making such a switch. For one, according to Jiang, farms in China are reluctant to use organic fertilizer as this requires more labor, and labor costs have increased greatly in recent years. In addition, the country may not be able to find enough organic fertilizer to use if all the farmlands are replaced with organic fertilizer, Jiang said. Jiang and his team suggested that the Chinese government could encourage farmers to use half the amount of chemical fertilizer while the rest is replaced with organic ones. A combination of organic manure and chemical fertilizer demonstrated the best result in improving soil quality and crop yields, while decreasing greenhouse gas emissions, the scientists said. Want to read more stories like this? Click here to start a free trial to EE -- the best way to track policy and markets. ABOUT CLIMATEWIRE – The politics and business of climate change ClimateWire is written and produced by the staff of EE Publishing, LLC. It is designed to provide comprehensive, daily coverage of all aspects of climate change issues. From international agreements on carbon emissions to alternative energy technologies to state and federal GHG programs, ClimateWire plugs readers into the information they need to stay abreast of this sprawling, complex issue.
Jiang Gaoming publicated in Chinadialogue (London)on July 05, 2011 Success at an experimental farm in eastern China strengthens the case for investing in organic agriculture as a basis for building food security, writes Jiang Gaoming. “Unfortunately, China’s government and scientists are placing their hopes in increasing the yield of a single harvest – planting so-called ‘super crops’.” Related articles Slideshow: organic overtures February 26, 2010 Beware the GM giants January 18, 2010 Removing chemicals from our food August 14, 2009 My team of b otanists at the Chinese Academy of Sciences has completed test plantings of organic wheat at the Hongyi Organic Farm in the eastern province of Shandong, with exciting results: for every mu of land(around 667 square metres), the farm harvested 480.5 kilograms of wheat. In 2010, the test field produced 547.9 kilograms of corn per mu .That means the plot can produce a total annual harvest of more than one tonne of grain. Shandong has been gripped by severe drought this year. Where fertiliser, pesticides and herbicides were used, even the best harvests yielded only 250 to 300 kilograms of grain; the worst, a couple of sacks. Some farmers have been left staring at their sparsely growing wheat and wondering if they should just give up. Some years ago, I proposed that China make efforts to develop its organic farming, or eco-farming sector, but was told that people would starve as a result. Agricultural experts have continued to spread that idea, and many academics and officials have accepted it unquestioningly. As a result, ecologists have shied away from eco-farming, while biotech experts continue to rave that genetically modified crops are the only possible solution to China’s food security issues. In 2007, my research team started experimenting in a field in Jiangjiazhuang, in Shandong’s Pingyi county. This was the worst land in the village, leased to us for only 110 yuan (US$17) per mu – a plot of the same size on good land near the village would have cost 300 yuan (US$46). The ground was rocky, and the soil only 20-centimetres deep. Thirty years ago, the community had used this piece of land as a threshing ground, since not much could be grown on it. It was this kind of land on which our team of scientists started trialling organic methods, strictly avoiding the use of man-made fertiliser, pesticide, herbicide, additives (manure from pig and chicken farms are polluted with additives), agricultural membrane and GM technology. Five years later, production has clearly increased. Even the locals find it hard to believe this organic miracle. Zhou Jinglin, secretary of the local Communist Party branch, told a reporter from Shandong’s television network about the changes in detail. And, having seen the trial for themselves, nearby farmers have become more enthusiastic about eco-farming. The methods used by the Chinese Academy of Sciences experts included: taking straw normally burnt off by farmers and processing it into fodder for cows, saving 1,500 yuan to 2,000 yuan (US$232 to US$309) per head of cattle; using some of the cow manure to make methane, to be used as an energy source, and the rest as quality organic fertiliser for the fields; and tackling pests with “physical and biological” methods – for example, insect light traps were used all year round, and chickens were kept in the field and fed on the insects. Weeds were hoed up and used as organic fodder for geese, fish and locust farming; and appropriate levels of irrigation used to maintain soil moisture. These methods allowed ecological restoration of unproductive land that had been polluted with fertiliser, pesticide and herbicide and allowed production levels to increase. In future, it should be simple to make eco-farming profitable – and the method for achieving this is straightforward: simply double the price of truly organic grains to over four yuan (US$0.6) per kilogram. Then the farmers will follow the scientists, and profits from farming will increase from about 1,000 yuan (US$155) per mu today to about 3,000 yuan (US$464) per mu . If the government passed that increase in price directly on to farmers, China’s food security would be assured without polluting the environment. For an investment of only one trillion yuan (US$154.6 billion), China’s government could prevent farmers abandoning their farms and reduce imports of genetically modified foods. That is only one third of the spending earmarked for pollution and environmental management during the 12 th Five-Year Plan period. In highly polluted areas, agricultural nonpoint source pollution (such as agricultural runoff) accounts for 70% of total pollution – much more than emissions from industry. Widespread eco-farming would help to put an end to this kind of contamination, as well as greatly reducing the sector’s greenhouse-gas emissions (it is more energy efficient than conventional agriculture). Agricultural experts will pay any price to obtain higher theoretical yields – with large quantities of fertiliser, pesticide and herbicide, they can achieve wheat harvests as high as 700 kilograms per mu in trials. But these kinds of yields are restricted to scientific experiments and, since they make no profit, mean nothing to farmers who simply want to increase their income. Eco-farming is essential for the future survival and progress of humanity – without it, harmonious urban-rural development is impossible. The United States is blazing a trail in this regard: it has energetically developed eco-farming as a way of boosting health and protecting the environment. Between 1992 and 2008, the number of US government-certified organic farms increased more than threefold, from 3,857 to 12,941. And, although initial investment in an organic farm is higher than for a conventional farm, the benefits are clear – the average turnover of an organic farm in the United States is US$217,000 (1.4 million yuan) compared to just US$135,000 (873,000 yuan) for all farms. In 2007, US organic farms with sales of US$1 million or above provided the vast majority (73% according to a report by researchers at the University of California) of the country’s total organic produce. While more and more US consumers are eating organically produced food, in China today, less than 0.01% of the population has access to the same: there is a bright future for this market. Raising food production through the use of organic fertiliser would allow low-yield fields to become medium-yield, and medium-yield fields to become high-yield, while high-yield fields would consistently be able to produce more than one-tonne of grain. Stabilising high-yield fields at this level would mean 600 million mu of good quality agricultural land could produce 600 million tonnes of grain – more than China’s current total production of 500 million tonnes. China has wide areas of land where two crops can be grown in a single year (so-called “ double cropping ”): all of Henan, Shandong and Jiangsu, in east China, parts of Hebei and Shanxi in the north, as well as Shaanxi further west and the provinces in the middle and lower reaches of the Yangtze River, all have the necessary warmth and rain. Unfortunately, China’s government and scientists are currently placing their hopes for future food security in increasing the yield of a single harvest – planting so-called “super crops”, such as “ super rice ”, “ super wheat ” and “ super corn ”. But in reality, grain-harvested areas are shrinking and farmers are leaving the land due to their losses. If this trend cannot be reversed, then better strains of crops will be of no use. Currently, the Chinese government’s investment in eco-farming and organic research is, when compared to the 24-billion yuan (US$3.7 billion) budget for developing genetically modified crops, virtually zero. Agricultural resources are rising in price, grain imports are increasing and funds intended to benefit farmers often do not reach them. Moreover, there is a gap between agricultural research and actual yields, and farmers are less and less inclined to plant grain crops. It is time the Chinese government took another look at organic agriculture. By employing effective methods, boosting farmers’ enthusiasm for grain crops, nurturing the land at the same time as using it and assuring agricultural businesses can make a profit, the Chinese people can bring China’s food supply under their own control. Jiang Gaoming is chief researcher at the Chinese Academy of Sciences’ Institute of Botany. Homepage image from Hongyi Organic Farm
Please open the online version of this message if the HTML is not correctly displayed. ELEVENTH TETRAHEDRON SYMPOSIUM Frontiers of Organic Chemistry 22 - 25 June 2010 ? Beijing, China 4 weeks to submit poster abstracts Submit by 28 February 2010 at www.tetrahedron-symposium.elsevier.com *** Special subscription offer for first 400 abstracts submitted *** NEW! ONLINE REGISTRATION NOW OPEN Join international delegates and speakers for the Eleventh Tetrahedron Symposium for a comprehensive and wide-ranging review of all aspects of organic synthesis, bioorganic, medicinal and computational chemistry, molecular recognition and the organic chemistry of materials. INVITED SPEAKERS Hear from the following internationally renowned experts: Karen N. Allen, Boston University, USA Matthias Beller, University of Rostock, Germany Dale L Boger, The Scripps Research Institute, USA Sukbok Chang, KAIST, Korea Remi Chauvin, Laboratoire de Chimie de Coordination, Toulouse, France Chien-Tien Chen, National Taiwan Normal University, Taiwan, China P. Andrew Evans, University of Liverpool, UK Shu Kobayashi, University of Tokyo, Japan Dawei Ma, SIOC, Shanghai, China Shengming Ma, East China Normal University, Shanghai, China David W.C. MacMillan, Princeton University, USA Peter H Seeberger*, ETH Zrich, Switzerland Brian M. Stoltz*, California Institute of Technology, USA Yongqiang Tu, Langzhou University, China Rik R Tykwinski, University of Alberta, Canada Jianbo Wang, Peking University, China Yoshinori Yamamoto, Tohoku University, Japan Dan Yang, University of Hong Kong, China Qilin Zhou, Nankai University, China *Winners of the Tetrahedron Young Investigator Award View preliminary programme information CALL FOR POSTERS Researchers are invited to submit abstracts for presentation within the large poster sessions which will supplement the invited oral programme. 300 word abstracts should be submitted online at www.tetrahedron-symposium.elsevier.com by 28 February 2010. A free online subscription to Drug Discovery Today will be given to the first 400 abstracts submitted and accepted for poster presentation. The Eleventh Tetrahedron Symposium is organized and hosted by Elsevier , publisher of Tetrahedron, Tetrahedron Letters, Tetrahedron: Asymmetry, Bioorganic Medicinal Chemistry, Bioorganic Medicinal Chemistry Letters and Drug Discovery Today. ORGANIZING COMMITTEE Steve Davies, University of Oxford, UK Leon Ghosez, European Institute of Chemistry and Biology (IECB), France Tamio Hayashi, Kyoto University, Japan Guoqiang Lin, SIOC, Chinese Academy of Sciences, Shanghai, China (Honorary Chairman) Zhangjie Shi, Peking University, China (Secretary) Richard Taylor, University of York, UK Yongqiang Tu, Lanzhou University, China Herbert Waldmann, Max Planck Institute of Molecular Physiology, Dortmund, Germany Jianbo Wang, Peking University, China Meixiang Wang, Tsinghua University, China Zhenfeng Xi, Peking University, China (Chairman) Zhu-Jun Yao, SIOC, Chinese Academy of Sciences, Shanghai, China (Secretary) Lihe Zhang, Peking University, China Qilin Zhou, Nankai University, China For full information visit www.tetrahedron-symposium.elsevier.com
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