标签归档：李军

SCP

Kenya Visit on 4-15 August

During 4th-15th October, four people of us (Gan Zhang, Jun Li, Shizhen and Xin Liu) were invited to visit University of Nairobi for the purpose of establishing academic collaborative relationship under framework of Belt and Road Initiative “Southern Contaminants Programme”. Gan was invited to deliver a speech titled “China Education System, Role and Research at SKLOG” to students and colleagues of Institute of Nuclear Science and Technology. He received a great deal of praise as Prof Michael who is Acting Director of the institute promptly expressed strong intentions to cooperate. Shizhen and Xin demonstrated standard operation of passive air samplers. Ten PASs will be quickly deployed at 5 sites of Nairobi city which is part of air monitoring network of the project. Two students of Nairobi-U are arranged to visit GIG soon after. They will also participate “SCP training class” in November. We also visited CAS Sino-Africa Joint Research Center (SAJRC) located inside campus of Jomo Kenyatta University of Agriculture and Technology.

The director of SAJRC Dr. Wang Qingfeng show us around the center.

Wet chemistry laboratory of SAJRC.  Made in China.

Meet with Professor Gatari after arrival, in a nice restaurant.

We being foreigners. @Kenyan National Museum.

First formal meeting with Prof Michael Gatari @UoN.

Short but happy talk with Vice Chancellor of UoN.

Students of UoN learn how to assemble the passive air sampler. With their participation, a PAS was, demonstratively, deployed on the roof inside campus of UoN which means the air monitoring network of the project has expanded to East Africa.

In the middle is an active air sampler from Prof Ojran’s group of Stockholm University. They have now 4-5 years of Hi-vol sampling in Nairobi.

Prof Gan delivering a speech on China Education System, Role and Research at SKLOG. Gan is always a good speaker.

Group photo with colleagues and MSc students of Institute of Nuclear Science and Technology. Another great achievement along the maritime silk road.

Behind us is the great rift valley, extending 9600 Km from the Red Sea to Mozambique.

Skyline, savannah, jeep and a girl.

On the Massai Mara savannah. The umbrella thorn Acacia could be the most typical/only tree on the savannah.

Ladies been escorted by a handsome soldier by the Massai River. There are crocodiles and rhinos in the water. He is 30 years old.

Massai jumping dance.

Guess, which way does water drain at the equator?

Our driver, Richard, happily showing us the coffee tree. This was the first time we saw a coffee farm.

This is the first time we’ve seen Gan collect samples.

Not far behind us is Mt Kenya (5199 m asl), the second highest mountain in Africa.

SCP

Workshop on Environmental Monitoring Along the 21st Century Maritime Silk Road

On May 26-27th, workshop on Environmental Monitoring Along the 21st Century Maritime Silk Road took place at Room 308 of Biaoben Building, Guangzhou Institute of Geochemistry, CAS. The workshop was under a project of “Southern Contaminants Programme (SCP)” “南方污染观测与研究计划”, a CAS Belt & Road Initiative (中国科学院“一带一路”科技合作专项). Totally, more than 20 people participated the workshop, including two steering committee members of the project, Prof. Kevin C Jones from Lancaster University of UK and Prof. Mohamad Pauzi Bin Zakaria from University of Malaya, and six international partners, Dr. Muhammad Mansha from Space and Upper Atmosphere Research Commission of Pakistan, Dr. Jabir H. Syed from COMSATS Institute of Information Technology of Pakistan, Dr. Dwi Hindarti from Indonesian Institute of Sciences, Dr. Le Quang Dung from Vietnam, Prof. Md. Ahsan Habib from University of Dhaka, Bangladesh, and Mr. Simion Kipkorir Bartilol from University of Nairobi, Kenya. We also specifically invited Prof. Hanping Zhuang, President and CEO of Jireh Technology of China, and Miss Ming Liu, Chief Representative of Technology and Innovation at the British Consulate-General Guangzhou. The workshop mainly consists of five sessions including welcome and background introduction by Gan, participants’ introductions, roundtable discussions, group discussions and lab tour. The workshop provides a good opportunity to meet and discuss deeply with each SCP partner, thus leading an extension of the international research network on toxic chemicals from East South Asia to South Asia and East Africa.

Icebreaker at Ramada Hotel
Welcome and background introduction by Prof Gan, head of the project.
Lab tour.
Group discussions. Participants were divided into three groups and discussed questions proposed in the previous sessions.
Back row from left to right: Ming Liu (刘明), Mohamad Pauzi Bin Zakaria, Kevin C Jones, Mahdi Safaei Khorram, Md. Ahsan Habib, Jabir H. Syed, Simion Kipkorir Bartilol, Manqing Wu (吴曼青), Guangcai Zhong and Hanping Zhuang (庄汉平). Front row from left to right: Wenwen Chen, Jun Li, Xin Liu, Dilanka, Le Quang Dung, Biao Jin, Gan Zhang, Muhammad Mansha, Dwi Hindarti and Shizhen Zhao.

 

Photo taken in front of Zhenhai Building
Waiting for the amazing Peal River night cruise
研究方向

碳十四 (Radiocarbon)

155条评论

环境14C技术与应用

主要研究人员：张干，朱三元，成志能，钟广财，李军，刘俊文，张向云，姜懿珊，莫扬之，苏涛，孙悦，徐步青

地球上的放射性碳同位素（14C）主要有两个来源，一是宇宙射线下由14N同位素在大气中生成（图1），二是以1960-1970年代为高峰的人类核试验产生的14C在大气中的衰变遗存。二者相互叠加，构成现时大气14C的背景丰度（“现代碳”，Contemporary carbon）。由于核爆高峰期渐行渐远，大气“现代碳”的14C丰度正处于持续衰减中（图2）。

14C具有5730年的半衰期，衰变产物为14N（图1）。因此，源于石油、煤等化石燃料（经上亿年衰变）燃烧的C将不具有放射性（“死碳”）；而源于生物质排放及燃烧的碳，将具有与同期大气相近的“现代碳”14C同位素丰度（图2）。故而，利用14C技术，可有效判识“死碳”和“现代碳”对有机质的相对贡献比例，提供其来源信息。

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图1 天然14C的生成和环境命运 (Libby, 1949, Science。Libby因14C工作获Nobel奖)

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图2 不同地表植被（当年生、10年生)、微生物和土壤有机质（SOM）14C丰度的时间变化（Trumbore, 2009, Annu. Rev. Earth Planet. Sci.）

依托有机地球化学国家重点实验室的14C专用加速器质谱（AMS），研究组致力于建立较为完善的AMS-14C分析前处理方法和装置，并将其应用于大气气溶胶、沉积碳埋藏、土壤碳动态等研究领域。目前已建立的技术系统如：

（1）基于热化学原理的两阶段加热气溶胶OC/EC分离-捕集系统（图3，Zhang Yanlin et al., NIMB, 2010; Liu Di et al., 2013, ES&T），经石墨化制靶，以固体源AMS测定14C丰度；

（2）基于OC/EC商用分析仪（Sunrise TOT）的微量样品OC/EC分离制备系统（图4，参考Zhang Yanlin et al., 2012, ACP），用于对气溶胶中的有机质进行分离，并作为CO2收集，以气体源AMS测定14C丰度；

（3）基于催化加氢技术（hydropyrolysis）的有机碳、黑碳（OC-BC）分离方法和装置（图5）。

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图3 基于热化学的两阶段气溶胶OC、EC分离制备系统。Zhang YL, 2010, NIMB; Liu D, 2013, ES&T.

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图4 基于商用OC/EC (TOT)分析仪改装的微量样本OC、EC分离制备与AMS气体源14C测定技术。参考Zhang YL 2012, ACP.

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图5 催化加氢装置。

在此研究方向，我们与瑞士Bern大学Sonka Szidat研究组、瑞典斯德尔摩大学Orjan Gustufsson研究组具合作关系和人员交流。

从2015年开始，受国家基金重点、面上项目和广州市有关项目的支持，相关的方法和技术正/将分别用于以下研究：（1）中南半岛生物质燃烧污染排放；（2）珠江三角洲/广州市灰霾的物质示踪和源解析；（3）河口/海岸带沉积碳埋藏与碳循环过程；（4）森林土壤碳动态。

目前，张向云正完善催化化加氢分离OC/BC的方法；姜懿珊正应用PLFA的单体14C信息，探讨森林土壤碳动态；莫扬之在探索以14C示踪气溶胶中棕碳（BrC）吸光组分的来源；苏涛探讨以14C对气溶胶PMF源解析结果进行制约；徐步青开始研发大气中多元酸（草酸等）的单体化合物分离与14C测定方法；孙悦正建立基于苯多酸（BPCA）的黑炭（BC）和水溶黑炭（DBC）的14C测定技术。