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    我與中國的“化學反應”

    2020-09-26 02:06:40戴偉DavidEvans孫夢格
    國際人才交流 2020年9期
    關鍵詞:化學反應北京化工大學科普

    文/戴偉(David G. Evans) 譯/孫夢格

    我十一二歲時,有兩大興趣:化學和中國!我知道我對化學產生興趣的原因,那是在花園里進行的激動人心的實驗中,我看見了一抹新世界的神秘曙光。而我對中國的興趣也緣于與此類似的好奇心。當時是1970年代初,中國尚未改革開放,我們在英國很少能看到關于中國和中國人民的新聞和信息。在迫切的求知渴望下,我通過中國駐倫敦大使館,訂閱了《北京周報》(當時的名字),開始每周閱讀有關中國的新聞。

    When I was around 11 or 12 years old, I had two main hobbies and interests. One was chemistry, and the other was China! I know where my interest in chemistry came from: it was doing lots of exciting experiments in our garden shed which began shining light on the mysteries of a new world. I think my interest in China was sparked by a similar sense of curiosity: I am talking about the early 1970s, before the start of Reform and Opening,so we in Britain received very little news and information about this huge country and all its people, which made me want to understand more. Through the Chinese Embassy in London I subscribed toPeking Reviewas it was then and began to receive a weekly update of news from China.

    對化學、對中國始終保持興趣

    我先在牛津大學攻讀了學士和博士學位,隨后又進入了??巳卮髮W化學系工作,其間,我一直保持著對化學的興趣。同時也沒有失去對中國的好奇。1987年,我終于得到機會,參加了在南京舉辦的“國際配位化學會議”,這是我第一次來中國。這次經歷更加激發(fā)了我對中國的興趣,此后我每年或每兩年都要來一次中國??吹竭@個我關心的國家和到訪過的大學正在迎來前所未有的飛速發(fā)展機遇時,我毫不猶豫地在1996年加入了北京化工大學,自此就幸福地工作、生活在這里。

    在大學的教學研究之外,我一直在尋找機會向中國的學生科普化學知識,激發(fā)他們對化學的興趣,就像我小時候一樣。春節(jié)期間,我會經常拜訪中國鄉(xiāng)村里的朋友并給孩子們做一些科普。我記得有一年,我從村子的商店里買到了一些醋和小蘇打,給孩子們制作了“火山”,發(fā)射了口香糖“火箭”,度過了一段愉快的時光。

    Maintaining my interest in chemistry and China

    I maintained my interest in chemistry by studying as an undergraduate and PhD student at Oxford University and then joined staff of the chemistry department in Exeter University. I had not lost my curiosity in China, however, and was able to visit for the first time in 1987, when the International Coordination Chemistry Conference was held in Nanjing. This visit reinforced my interest and I subsequently visited once or twice each year.Having seen how the country and the universities I had visited were beginning to develop rapidly, I jumped at the chance to move to Beijing University of Chemical Technology BUCT in 1996 and have been there happily ever since.

    Apart from my university work, I was always looking for a chance to introduce Chinese children to chemistry, and see if it could inspire the same sort of interest in them that it had in me all those years ago. I did a few ad hoc sessions with the children of friends whose countryside home I regularly visited over the Spring Festival. I remember one year I were able to buy some vinegar and baking soda from the village shop and had a great time making “volcanos” and launching chewing gum bottle“rockets”.

    英國皇家化學會,正式科普的機會

    2011年,我得到了很多更穩(wěn)定、更正式做科普的機會。那一年是聯(lián)合國教科文組織的國際化學年。幾年前,我在北京設立了英國皇家化學會(RSC)的分支,RSC運營著大量的書籍和學術出版業(yè)務,但作為一個非營利組織,也會用出版部門產生的盈余開展慈善活動,增加公眾對化學的興趣。當時RSC的主席大衛(wèi)·菲利普教授迫切地感到,除了幫助組織國際化學年的一些活動外,RSC也應該嘗試開展一些屬于自己的長期活動,擴大國際化學年的影響。他非常開明地決定,給每個地方的RSC分支機構(共有100多個)一筆1000英鎊的資金,要求他們嘗試一些此前從未做過的事情。在收到國際化學學會撥付給北京分會的款項后,一次偶然的機會,我在北京和英國朋友海倫·博伊爾一起吃晚餐。海倫成立了一家慈善組織“打工子弟基金會”(MCF),專門為在北京的打工子弟小學的學生上課。海倫的基金會里有一群志愿者,他們會在周末給孩子們上課,主要教英語,也會教音樂和藝術。晚餐時,海倫突然問道:“你能不能來教我的孩子們學化學呢?”我說:“好啊,我剛從RSC得到一筆經費,我們看看能做些什么吧!”于是,我購買了一整套燒杯、試管、量筒和其他設備(為避免發(fā)生事故,我用塑料代替了傳統(tǒng)的玻璃),還買了一些無毒的化學試劑、兒童尺寸的實驗室外套,以及最重要的防護設備護目鏡。那是一個周六,天剛蒙蒙亮,我和北京化工大學的幾個研究生志愿者就把我們的設備搬上了小貨車,向著目的地出發(fā)了。學校在遠離市中心的郊區(qū),離得很遠。孩子們看到我們真的很高興,在穿上實驗室外套、戴好護目鏡開始實驗之前,就興沖沖地幫助我們布置教室。我將四個孩子和一個研究生分為一組,開始了此次化學實驗。孩子們玩得很開心。此后,每次上課之前我們都會問他們上次做過的活動,從他們的回答中,我也能感受到,他們真的學到了很多化學知識,并且開始培養(yǎng)出一種科學的思維方式。

    RSC provides a chance to popularize science

    My chance to something more formal and substantial came in 2011, which was the UNESCO International Year of Chemistry IYC. I had set up a Beijing Local Section of the Royal Society of Chemistry (RSC) a couple of years earlier. RSC has a substantial book and academic publishing operation but, as a not-for-profit organization, uses the surplus generated by the publishing section to run charitable activities promoting interest in chemistry. The RSC President at the time, Professor David Phillips, felt strongly that as well as organizing activities during IYC itself, RSC should try to set up some longer-term activities to mark IYC in a more sustainable way. He had the inspired idea to give every Local Section and Interest Group (over 100 in all) one thousand pounds and challenged them to do something outside their normal remit. By chance, having just received the Beijing Local Section’s IYC Challenge grant, I was having dinner with a British friend in Beijing, Helen Boyle, who had set up a charity (MCF) to organize classes for children attending migrant schools in Beijing. Helen had a team of volunteers going into schools at weekends, mainly teaching English, but also some music and art. Over dinner, Helen suddenly said “Look,can’t you teach my kids chemistry?”. I said “Well, as it happens I have this grant from RSC, so let’s see what we can do”. I bought a whole load of beakers, test tubes, measuring cylinders and other apparatus all plastic, rather than the traditional glass, to avoid accidents, nontoxic chemicals, child-sized lab coats and—most importantly of all—safety glasses. Then at the crack of dawn on Saturday mornings—the migrant schools are a long way outside the city center—my team of postgraduate student volunteers from BUCT loaded all the kit into our hired minibus and we set off. The children were really excited to see us and willingly helped set up the classroom before putting on their lab coats and safety glasses and starting to do the experiments.We divided them into pairs with a postgraduate looking after a table of four pairs and the chemistry began. They had great fun,but by asking them at the start of each lesson about what they had done last time, we could see that many of them were also learning about chemistry and beginning to develop a scientific way of thinking.

    戴偉教授連續(xù)多年參加全國科技活動周有關活動。圖為2015年全國科技活動周期間,時任中央政治局委員、國務院副總理劉延東和時任北京市委書記郭金龍觀看戴偉教授做實驗并親切交流

    我們繼續(xù)和打工子弟小學合作,并陸續(xù)收到了更多來自公立學校和其他組織的邀請,如北京科技教育促進會。有時,我和研究生助理會去學校的科學博覽會,開展動手實踐的課程;有時,則是我獨自一人去做實驗演示。因為化學實驗經常有火花和爆炸,所以我們不能讓孩子們自己操作。我通常會先問學生,是否相信我可以通過在蠟燭上噴水的方式把蠟燭點燃,他們當然會說不相信,然后我會讓孩子們一起用英語倒數(shù)“三、二、一”,接著就把“水”噴灑在蠟燭上,此時蠟燭就會迸發(fā)出火焰。三百多名學生興奮地跳上跳下,并驚呼著“哇”,讓實驗課堂開了個好頭。當然,等孩子們冷靜下來時,我會告訴他們,我到底是怎么做到的而不是像魔術師那樣保持神秘。我噴灑的“水”實際上是酒精,并且,在演示之前,我在蠟燭上挖了一個小坑,在其中填充了一些紅色的固體。接下來,我不用蠟燭,再次重復上述演示過程,孩子們就會看到,其實是紅色固體和酒精引發(fā)了火苗,而紅色固體燃燒后殘留了綠色固體。在這個過程中,他們看到的就是化學的本質——將一種或多種材料(在這個實驗中就是酒精和紅色固體)轉換為新的材料(綠色固體)。

    We have continued to work with the migrant schools, but also began to receive more and more invitations from state schools and other organizations. Sometimes the postgraduates and I run hands-on practical classes at school science fairs, and at other times I go alone and do a lecture demonstration of experiments that—since they often involve fire and explosions—we couldn’t let the children do themselves. I usually start by asking the students if they think I can light a candle by spraying water on it. Of course they don’t believe I can, but I ask them to help me by counting down “three, two, one” in English and then I spray“water” onto my candle which bursts into flame. The sight of 300 children jumping up and down shouting “Wow!” gets the lecture off to a good start. Of course, when they calm down I tell them that—unlike a magician, who won’t reveal their secrets—I will tell them how I did the trick. The “water” is actually alcohol and before the lecture I dug a little pit in the candle and place some red solid in it. By repeating the process without the candle they can see that it is the red solid and alcohol which causes the fire, and afterwards we are left with a green solid.From this they can see the essence of chemistry—changing one or more materials the alcohol and red solid, in this case into a new material the green solid.

    北京化工大學,面向公眾科普

    除了皇家化學會,我還得到了北京化工大學的大力支持。根據(jù)習近平總書記在全國科技創(chuàng)新大會、兩院院士大會、中國科協(xié)第九次全國代表大會上的指示,要把科學普及放在與科技創(chuàng)新同等重要的位置。希望廣大科技工作者以提高全民科學素質為己任,把普及科學知識、弘揚科學精神、傳播科學思想、倡導科學方法作為義不容辭的責任。北京化工大學將我的大部分工作職責轉換為面向公眾的科普。例如,我每年都會在北京化工大學副校長和招生辦公室主任的陪同下,訪問全國大約50或60所頂級中學。在同事們介紹完北京化工大學之后,我會給學生們(通常是數(shù)百人,有時超過千人,一次在長沙學生人數(shù)超過了2000人)演示與過氧化氫有關的化學實驗,和他們在中學課堂里學到過的化學知識緊密相連。實驗演示都大受歡迎,因為許多學生告訴我,他們以前從未做過任何實驗。學生給我反饋的評價包括:“這些實驗遠遠超過了課本的局限性,大大地提升了我學習的熱情和好奇心,將成為我學習路上的不竭動力”“我們曾對自己在書本上看到的東西深信不疑,可戴偉告訴我,那些優(yōu)秀的科學家只有不斷地質疑,才會不斷地進取,那將指引我們這代人成長為未來的科學開拓者”,或者是更為簡短但直截了當?shù)脑u價:“想不到枯燥的化學反應,竟然有如此巨大的魅力”。

    BUCT strongly supports our outreach work

    In addition to RSC, I have also received strong support from BUCT. Following the guidance of President Xi Jinping on the importance of popularizing science, the university converted most of my job description to involving outreach. For example,I each year I visit around 50 or 60 of the top high schools all over the country in the company of a BUCT Vice-President and the head of the Admissions Office. After my colleagues introduce BUCT, I give the students usually several hundred,but sometimes over 1000, or once in Changsha, as many as 2000 a lecture demonstration based around hydrogen peroxide which links exciting experiments with their high school curriculum.This usually receives a rapturous reception, mainly because many students tell me they have never done any experiments before.

    BUCT has also supported our outreach activities in many other ways as well. For example, after the undergraduates moved to our new campus in Changping, BUCT converted one of the former undergraduate teaching labs into an outreach lab, so we are now able to bring students—including those from migrant schools—into the lab to do experiments.

    We have also been delighted to be invited on several occasions to take part in the National Science Week. In addition to the large numbers of enthusiastic children who have carried out chemistry experiments with myself and the team of BUCT postgraduates, we have welcomed several honored guests to our laboratory, including Liu Yandong-the former Vice Premier,Wan Gang-the former minister of the Ministry of Science and Technology (MOST) , Wang Zhigang-the minister of MOST,Guo Jinlong-the former Party chief of Beijing, and Cai Qi-the party chief of Beijing. Madam Liu Yandong was particularly keen to do an experiment with the children: I gave her a flask containing a yellow liquid, which turned red when she shook it, and then green when she shook it again, and then she asked the students for their hypotheses about what was happening. Madam Liu Yandong was very excited, because she said it took her back 50 years to her time as a student in the Department of Chemical Engineering, Tsinghua University.Although this year’s National Science Week was constrained by the coronavirus outbreak, I was still able to give two lecture demonstrations to young children (sitting one meter apart).They were very excited to see the chemical reactions and generated a great atmosphere in the classroom.

    北京化工大學還以其他許多方式支持著我們。比如,當本科生搬到昌平的新校區(qū)后,大學將以前的一間本科教學實驗室轉變?yōu)榱斯娬故緦嶒炇?,所以我們現(xiàn)在可以讓學生,包括打工子弟學校的學生進入到大學校園中做實驗。

    我們也很高興多次應邀參加全國科技活動周活動。除了一大批和我的團隊一起做實驗的孩子們之外,我們的實驗室還迎來了幾位特殊的嘉賓,其中包括原副總理劉延東、原科技部部長萬鋼、現(xiàn)任科技部部長王志剛、原北京市原市委書記郭金龍與現(xiàn)任北京市委書記蔡奇。劉延東女士非常喜歡和孩子們一起做實驗:我給了她一個裝有黃色液體的燒瓶,她搖晃燒瓶后,液體變成了紅色,再搖晃一次,液體又變成了綠色,然后她會請學生們猜想為什么會發(fā)生這種變化。劉延東女士說,做實驗的經歷激動人心,讓她想到了五十年前自己在清華大學化學工程系學習的時光。盡管今年的全國科技活動周受到了疫情的影響,但我仍舊給孩子們展示了化學實驗,孩子們只能間隔坐開,但他們的歡笑聲依然令人激動。

    “戴博士實驗室”

    雖然我很幸運能夠與成千上萬聰明的中國學生直接互動,但這仍然只能覆蓋很少一部分人。2018年,我的助手索樂樂在回到山東農村過春節(jié)時,發(fā)現(xiàn)他的朋友和家人都在談論短視頻平臺快手。他回到北京后,就建議我們把一些化學實驗的視頻放到快手上。他半開玩笑地說:“我覺得肯定沒有人會看的!”我說,科學家們都是通過做實驗來觀測結果的,我們要想知道結果怎么樣,就必須親自嘗試一下。而嘗試之后,我們發(fā)現(xiàn),真的有不少人會觀看我們的實驗演示!我們的平臺賬號“戴博士實驗室”在快手上有370多萬粉絲,其中一些視頻的播放量達到了1500萬次?!按鞑┦繉嶒炇摇痹谥T如抖音和嗶哩嗶哩等其他平臺上也有不少粉絲。這些平臺在吸引了大量的觀眾之外,還有其他優(yōu)勢。它們?yōu)槟切┑靥幤h小鎮(zhèn)或山村,很少有機會參與科學探索的年輕人,提供了親近化學的機會。同時,與“戴博士實驗室”的不期而遇,也讓那些不刻意尋找科普網站或頻道,只是隨意在網站或平臺上瀏覽其他休閑娛樂的普通人,有了和科學互動的機會。

    我之前提到過,我在全國各地講課時發(fā)現(xiàn),許多高中生進行化學試驗的機會非常有限,只能從書本上學化學,他們難免感到化學很無聊。造成這種現(xiàn)象的一部分原因是高考化學的局限性,還因為,許多學校的班級中可能有70或80名學生,一旦做實驗,就需要大量的玻璃器皿和試劑溶液,所以很難組織。為了解決這個問題,我們目前正在開發(fā)“微型化學實驗”項目,這個項目只需要簡單的設備和幾毫升的溶液,甚至可以在普通教室而不是實驗室中進行。我們于2019年夏季在北京開展了試點,由皇家化學會和快手共同贊助,三十名來自云南和湖北深度貧困地區(qū)的學生和老師,在免費提供設施的北京王府學校的大力支持下,參與了項目。這次活動取得成功之后,我們計劃今年在不同的深度貧困地區(qū)展開更多的試點,然而因為疫情的暴發(fā),我們不得不暫緩計劃。

    Going online: “Dr. Dai’s lab”

    Although I have been fortunate to be able to interact directly with many thousands of bright Chinese students, of course this is only a tiny fraction of the population. In 2018 when my assistant Suo Lele went back to the Shandong countryside for the Spring Festival, his friends and family were all talking about the short video platform Kuaishou. When he came back to Beijing, he suggested we should put videos of some chemistry experiments on Kuaishou. Half joking, he said “I’m sure noone will watch them!”. I said that since scientists must do the experiment to be sure of the result, we should have a go. And lo and behold, we found that people did watch them! Our site has over 37 million followers on Kuaishou and some of the videos have been watched over 15 million times. The site also has quite a few followers on other platforms such as Tik Tok and Bilibili.As well as reaching large numbers of people, these platforms have other benefits. They provide a way of bringing chemistry to young people in small towns or remote villages who have no,or very few, opportunities to take part in science activities, but also are a means of interacting with people who might not have thought about opening a science app or website, but find our site by chance when they are scrolling through the app looking for other types of entertainment.

    As I mentioned earlier, I have found on my travels that many high school students have very limited opportunities to do practical chemistry, and when it becomes all bookwork they find chemistry very boring. This is partly because of the constraints imposed by the college entrance exam, but also because in many schools there can be 70 or 80 students in a class so that is difficult to organize practical activities, since large amounts of glassware and reagent solutions are required. To combat this problem, we have worked on developing a program, which only require simple apparatus and a few milliliters of solution,and can even be carried out in a normal classroom rather than a laboratory. We ran a pilot program in Beijing in summer 2019 for 30 students and teachers from regions in deep poverty from Yunnan and Hubei which was sponsored by RSC and Kuaishou,with strong support from Beijing Royal School who provided their facilities free of charge. Following the success of this event,we had planned to start rolling out the program in regions in deep poverty in different parts of the country this year, but of course the coronavirus epidemic has meant we have had to put our plans on hold for the moment.

    為什么科普如此重要?

    很多人,有時甚至是其他科學家,經常問我為什么認為科普如此重要。當然,原因之一是我們希望激勵學生成為中國未來所需的科學家和工程師。例如,剛從東直門中學畢業(yè)的學生宋大有,在他還是小學五年級的時候,第一次參加了我們在北京科學嘉年華的活動。做完實驗后,他和我聊了很久,并且一直保持聯(lián)系,還參加了我們后續(xù)的許多活動。他此后就在家中自己進行化學實驗,并會在新年晚會和其他活動中給同學們做實驗演示?,F(xiàn)在,他已成為我們教學團隊的一員,能夠像研究生一樣有效地監(jiān)督做實驗的低年級同學。由于擔任輔導工作,又長得很高,小學生們經常叫他“叔叔”,而不是“哥哥”,第一次聽見這種稱呼,他嚇了一跳!在這里要特別宣布一則喜訊,恭喜宋大有同學在今年高考中,化學取得了滿分的好成績。當然,并不是每個參加我們活動的學生都會成為科學家,但是我希望每個人都能從中受益。除了教化學,我們還試圖幫助培養(yǎng)學生科學的思維方式。這是一項很重要的技能,因為當今世界,我們面對著許許多多的謠言和“假新聞”(例如,一個網站會告訴你每天喝六杯咖啡能活到99歲,而另一個網站卻會說每天喝六杯咖啡會致癌),每個人都需要具備科學的態(tài)度,才能從每天接收的大量信息中挑選出真實且準確的信息。

    展望未來,我很幸運有各種機會能夠訪問中國大陸所有的省、自治區(qū)和直轄市。在不久前的統(tǒng)計中,我發(fā)現(xiàn)還沒有去江西、廣西和西藏講過課或做過實驗。我希望能夠盡快完成這個目標,因此歡迎向我發(fā)出邀請!幾年前,我很榮幸受邀加入中國科學院老科學家科普演講團。盡管其中的大多數(shù)成員都已經退休,但還是有一些像我這樣的“年輕”的成員??吹綀F隊的成員(其中一些人已經七十多歲,甚至是八十多歲了)還能夠對為青少年普及科學保持著熱忱,我感到備受鼓舞,希望退休后,我也能夠像他們一樣。

    Why is doing outreach so important?

    People, sometimes even other scientists, often ask me why I think doing outreach is so important. One reason of course is that we hope to inspire students to become the scientists and engineers that China will need in the future. As an example, a student Song Dayou, who has just graduated from Beijing Dongzhimen High School, first took part in one of our activities at the Beijing Science Carnival when he was a primary school Grade 5 student. After doing the experiment with the other children, he spent a long time talking to me and then kept in touch and attended many of our future events. He also started doing chemistry experiments at home and doing demonstrations for his classmates during their New Year parties and other events. Now he has become a member of our teaching team, able to supervise the young students doing experiments as effectively as our postgraduates do. Being in a teacher role as well as quite tall, he often finds that the primary students call him uncle rather than brother, which came as a bit of a shock the first time! I just found out that Song Dayou got full marks in the College Entrance Chemistry Exam this summer. Of course not every student who takes part in our activities is going to become a scientist, but I hope that each one can still derive some benefit, because as well as teaching chemistry,we try to help students develop a scientific way of thinking. This is an important skill, because when faced with all the rumors and“fake news” available these days such as, one website tells you six cups of coffee a day will mean you to live to 99, while another will tell you six cups of coffee a day will cause cancer everyone needs a scientific attitude to pick out what is true and accurate amongst the vast amount of information that is fed to us every day.

    Looking to the future, I have been fortunate to be able to visit all of the Cities and provinces in mainland China for one reason or another. Counting up the other day, I found that there are only three—Jiangxi, Guangxi and Tibet—where I have not done a chemistry outreach lecture or class in a school or science museum. I hope to be able to complete the set sometime soon—so any invitations are welcome! Several years ago I was honored to be invited to join the Chinese Academy of Sciences group of senior scientists set up to popularize science. Although most of the members are retired, there are some “younger” members like me. It is really inspiring to see how the team members—some of whom are in their late seventies or even eighties—have maintained their enthusiasm for bringing science to young people, and I hope that when I retire I will be able to follow their example.

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