Preparation of polypyrrole/polyvinylalcohol (PPy/PV A)
composite foam electrode material
Xin Yi Wang a ,b ,Li Ping Heng b ,Nai Liang Yang b ,Qiang Xie a ,*,Jin Zhai b ,c
a School of Chemical and Environmental Engineering,China University of Mining &Technology,Beijing 100083,China
b Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China
c School of Chemistry an
d Environment,Beijing University of Aeronautics and Astronautics,Beijing 100081,China
Received 23October 2009
Abstract
Polypyrrole/polyvinylalcohol (PPy/PV A)foam was prepared by direct foam polymerization in water and then it was coated on the indium-tin oxide transparent conductive glass (ITO)to form conventional three-electrode cell.FTIR and UV–vis spectra were adopted to characterize the molecular structure and the absorption spectra of foam material,respectively.The porous structure of PPy/PV A foams and their photoelectric conversion behaviors were studied.The dimension of the pores is bigger than 100m m in https://www.doczj.com/doc/0c411418.html,pared with the smooth ?lm,the V oc and I sc of the foam ?lm enhanced by 1.58-fold and 5.59-fold,respectively.#2010Qiang Xie.Published by Elsevier B.V .on behalf of Chinese Chemical Society.All rights reserved.
Keywords:Conjugated polymers;Foams;Photoelectric conversion;Polymerization
The conductive polymer (CP)performs not only the functions of metals,semiconductors and ferromagnets,but also has the activity of electrochemical oxidation–reduction and the ?exibility of the mechanical properties and processability,which suggests that CP materials play an important role in the development of organic optoelectronic devices and electrochemical devices in the future [1–3].CP-based foams have many advantages,such as varied structure design,high chemical stability,and so on [4–7].Although the preparation of the foam polymer by conventional way needs a high-pressure vessel,a direct foam polymerization method was established and the foam materials utilizing conducting PANI were fabricated [8].
So far,some representative conductive polymer electrode materials have been synthesized [9,10].PPy has been regarded as the material that takes on the prospect of industrial application,because it not only shares common characters with other conductive polymers,but also has good air stability and strong electrochemical reversibility [11–13].The composite membrane of PPy has attractive application prospects in wide ?elds [14–16].
CP-based electrodes are well structured and have high surface area.Besides,its electrical conductivity can tune over a wide range [3,8,17–19].Up to present,PPy has been employed to PPy/TiO 2anode or solid electrolyte for dye-sensitized solar cells [20–22].Because of all those advantages mentioned above,PPy is promising in fabricating CP-based solar https://www.doczj.com/doc/0c411418.html,/locate/cclet
Available online at https://www.doczj.com/doc/0c411418.html,
Chinese Chemical Letters 21(2010)884–887
*Corresponding author.
E-mail address:dr-xieq@https://www.doczj.com/doc/0c411418.html, (Q.Xie).
1001-8417/$–see front matter #2010Qiang Xie.Published by Elsevier B.V .on behalf of Chinese Chemical Society.All rights reserved.doi:10.1016/https://www.doczj.com/doc/0c411418.html,let.2010.01.005
Herein,we prepared conductive PPy/PV A composite foam ?lm based on the method reported previously [8].Then the photoelectric conversion behavior was studied in details,?nding that the improvement of photoelectric conversion ef?ciency is achieved.
1.Experimental
At room temperature,3.5g PV A was dissolved into 45mL saturated ferric chloride (the oxidant)solution under mechanical stirring at 1000rpm for one hour [8].Then 600m L pyrrole was added slowly with microinjector and stirred for 8h.The smooth thin ?lm electrode was prepared for comparison.The scanning electron microscopy (SEM)images were obtained using a JEOL JSM-6700F scanning electron microscope at 3.0kV .UV–vis spectrum was measured with a Hitachi U-3010UV–vis spectrometer.Fourier transform infrared spectrum (FTIR)was measured on a Bruker Tensor 27spectrophotometer.The photoelectric conversion behaviors of the ?lms were measured by conventional three-electrode cell at AM 1.5simulated solar light (100mW/cm 2).
2.Results and discussions
From Fig.1,the characteristic vibrations are the symmetry stretching vibration peak of pyrrole central at 1559cm à1and the asymmetric stretching vibration peak of pyrrole at 1426cm à1.PPy’s steady-state is the p-type doping conductive state at room temperature.The characteristic absorption peaks at 1207cm à1and 837cm à1are ascribed to the miscellaneous doped states of PPy [23,24].The UV–vis absorption spectrum of the foam ?lm is shown in Fig.2.The band at 494nm is due to the p –p *absorption peak of long conjugated chain in polymer main chain,which also proves the presence of PPy [25].
The morphology of foam ?lm can be seen in Fig.3.The dimension of the pores is bigger than 100m m in diameter but the defects indicate the destruction of porous network structure.Fig.3(a)shows the surface of smooth ?lm.Obviously,the foam wall forms a continuous network structure,which ensures the overall conductivity.In addition,the density and the porosity of the as-prepared PPy/PV A composite foam are 0.2847g/mL and 85.57%,respectively,being obtained with nitrogen adsorption experiments.This kind of foam will have the potential applications in the photovoltaic devices.
Fig.4(a)shows the photocurrent generation at the foam ?lm and the smooth ?lm.It can be observed that the introduction of the foam will increase the photo-generated current density from 0.41m A/cm 2to 2.91m A/cm 2.As shown in Fig.4(b),a short-circuit current density (I sc )of 5.76m A/cm 2and an open-circuit voltage (V oc )0.054V for the foam ?lm were obtained.As compared,an I sc and a V oc were 1.03m A/cm 2and 0.034V ,respectively for the smooth ?lm.The V oc of the foam ?lm was increased by 1.58-fold,and I sc by about 5.59-fold.This result indicates that the foam structures of PPy/PV A composite increase the photoelectric properties more ef?ciently than the PANI/PV A composite foam reported before [8].
X.Y.Wang et al./Chinese Chemical Letters 21(2010)884–887
885
Fig.1.FTIR spectrum of the porous foam.
The relationship between photocurrent and bias voltage of the foam is shown in Fig.4(c).It is 12.23m A/cm 2under a bias voltage of à180mV .Anodic photocurrent generation is achieved when the applied bias voltage is larger than 30mV;and it is à13.40m A/cm 2when the bias voltage is 180mV .This shows that when a negative bias voltage is applied,this electric ?eld promotes the separation of the electron and hole and hence electron transfers in this pathway.On the contrary,when a positive bias voltage is applied,the electric ?eld depresses the electron transfer from ITO electrode to electrolyte,and hence the cathodic photocurrent decreases.In this case,when the positive bias potential is higher than 30mV ,the electrons are transferred from electrolyte to ITO electrode through the ?lm,which changes the photocurrent direction from cathodic to anodic.
3.Conclusions
PPy can be foamed directly by means of polymerization of pyrrole in water using PV A foam as a template,which broadens the application scope of the foaming-polymerization method reported previously.Moreover,the porous
X.Y.Wang et al./Chinese Chemical Letters 21(2010)884–887
886Fig.2.UV/vis absorption spectra of the porous
foam.
Fig.3.(a)and (b)top and section views of the prepared foam ?lm,(c)top view of prepared smooth ?lm,(d)optical photo of the prepared
electrode.Fig.4.Photoelectric conversion properties of PPy/PV A foams and smooth ?lms:(a)Photocurrent generation of the ?lms,(b)I–V characteristics of the foam and smooth ?lms,(c)Photocurrent response of the foam ?lm in applied electric ?elds.
X.Y.Wang et al./Chinese Chemical Letters21(2010)884–887887 foamy PPy enhances the photoelectric conversion behavior of the porous materials by improving the light capture ability.It shows the evidence for using different conductive polymer to fabricating CP-based solar cells.
Acknowledgments
This work was supported by the National Natural Science Foundation of China(No.20773142,50533030),the National Research Fund for Fundamental Key Project(No.2006CB806200,2006CB932100and2007CB936403)and 863project(No.2007AA032348and2008AA05Z308).
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的主体，要下功夫写好，关键是要写得既具体，又不繁琐；既概括，又不抽象；既生动形象，又很实在。总之，就是要写得很有说服力，让人一看便可得出够得上先进的结论。比如，写一位端正党风先进人物的事迹材料，就应当着重写这位同志在发扬党的优良传统和作风方面都有哪些突出的先进事迹，在同不正之风作斗争中有哪些突出的表现。又如，写一位搞改革的先进人物的事迹材料，就应当着力写这位同志是从哪些方面进行改革的，已经取得了哪些突出的成果，特别是改革前后的．经济效益或社会效益都有了哪些明显的变化。在写这些先进事迹时，无论是先进个人还是先进集体的，都应选取那些具有代表性的具体事实来说明。必要时还可运用一些数字，以增强先进事迹材料的说服力。 为了使先进事迹的内容眉目清晰、更加条理化，在文字表述上还可分成若干自然段来写，特别是对那些涉及较多方面的先进事迹材料，采取这种写法尤为必要。如果将各方面内容材料都混在一起，是不易写明的。在分段写时，最好在每段之前根据内容标出小标题，或以明确的观点加以概括，使标题或观点与内容浑然一体。 最后，是先进事迹材料的署名。一般说，整理先进个人和先进集体的材料，都是以本级组织或上级组织的名义；是代表组织意见的。因此，材料整理完后，应经有关领导同志审定，以相应一级组织正式署名上报。这类材料不宜以个人名义署名。 写作典型经验材料-般包括以下几部分： (1)标题。有多种写法，通常是把典型经验高度集中地概括出来，一
How to manage time Time treats everyone fairly that we all have 24 hours per day. Some of us are capable to make good use of time while some find it hard to do so. Knowing how to manage them is essential in our life. Take myself as an example. When I was still a senior high student, I was fully occupied with my studies. Therefore, I hardly had spare time to have fun or develop my hobbies. But things were changed after I entered university. I got more free time than ever before. But ironically, I found it difficult to adjust this kind of brand-new school life and there was no such thing called time management on my mind. It was not until the second year that I realized I had wasted my whole year doing nothing. I could have taken up a Spanish course. I could have read ten books about the stories of successful people. I could have applied for a part-time job to earn some working experiences. B ut I didn’t spend my time on any of them. I felt guilty whenever I looked back to the moments that I just sat around doing nothing. It’s said that better late than never. At least I had the consciousness that I should stop wasting my time. Making up my mind is the first step for me to learn to manage my time. Next, I wrote a timetable, setting some targets that I had to finish each day. For instance, on Monday, I must read two pieces of news and review all the lessons that I have learnt on that day. By the way, the daily plan that I made was flexible. If there’s something unexpected that I had to finish first, I would reduce the time for resting or delay my target to the next day. Also, I would try to achieve those targets ahead of time that I planed so that I could reserve some more time to relax or do something out of my plan. At the beginning, it’s kind of difficult to s tick to the plan. But as time went by, having a plan for time in advance became a part of my life. At the same time, I gradually became a well-organized person. Now I’ve grasped the time management skill and I’m able to use my time efficiently.
英语演讲稿：未来的工作 这篇《英语演讲稿范文：未来的工作》，是特地，希望对大家有所帮助！ 热门演讲推荐：竞聘演讲稿 | 国旗下演讲稿 | 英语演讲稿 | 师德师风演讲稿 | 年会主持词 | 领导致辞 everybody good afternoon:. first of all thank the teacher gave me a story in my own future ideal job. everyone has a dream job. my dream is to bee a boss, own a pany. in order to achieve my dreams, i need to find a good job, to accumulate some experience and wealth, it is the necessary things of course, in the school good achievement and rich knowledge is also very important. good achievement and rich experience can let me work to make the right choice, have more opportunities and achievements. at the same time, munication is very important, because it determines whether my pany has a good future development. so i need to exercise their municative ability. i need to use all of the free time to learn
雅思口语素材汇总之端午节 雅思口语素材:Dragon Boat Festival(端午节) Qu Yuan The Dragon Boat Festival, also called the Duanwu Festival, is celebrated on the fifth day of the fifth month according to the Chinese calendar. For thousands of years, the festival has been marked by eating zong zi (glutinous rice(糯米)wrapped to form a pyramid using bamboo or reed leaves) and racing dragon boats. The festival is best known for its dragon-boat races, especially in the southern provinces where there are many rivers and lakes. This regatta(赛舟会)commemorates the death of Qu Yuan , an honest minister who is said to have committed suicide by drowning himself in a river. Qu was a minister of the State of Chu situated in present-day Hunan and Hubei provinces, during the Warring States Period (475-221BC)(战国时期). He was upright, loyal and highly esteemed for his wise counsel that brought peace and prosperity to the state. However, when a dishonest and corrupt prince vilified Qu, he was disgraced and dismissed from office. Realizing that the country was now in the hands of evil and corrupt officials, Qu grabbed a large stone and leapt into the Miluo River on the fifth day of the fifth month. Nearby fishermen rushed over to try and save him but were unable to even recover his body. Thereafter, the state declined and was eventually conquered by the State of Qin. The people of Chu who mourned the death of Qu threw rice into the river to feed his ghost every year on the fifth day of the fifth month. But one year, the spirit of Qu appeared and told the mourners that a huge reptile(爬行动物)in the river had stolen the rice. The spirit then advised them to wrap the rice in silk and bind it with five different-colored threads before tossing it into the river. During the Duanwu Festival, a glutinous rice pudding called zong zi is eaten to symbolize the rice offerings to Qu. Ingredients such as beans, lotus seeds(莲子), chestnuts(栗子), pork fat and the golden yolk of a salted duck egg are often
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读书的好处是显而易见的,但是,在社会发展日新月异的今天,依然不乏对读书,对知识缺乏认知的人,《今日说法》中我们反复看到农民工没有和用人单位签订劳动合同,最终讨薪无果;屠户不知道往牛肉里掺“巴西疯牛肉”是犯法的;某父母坚持“棍棒底下出孝子”,结果伤害了孩子的身心,也将自己送进了班房……对书本,对知识的零解读让他们付出了惨痛的代价,当他们奔波在讨薪的路上,当他们面对高墙电网时,幸福,从何谈起?高质量的生活,从何谈起? 读书,让我们体会到“锄禾日当午,汗滴禾下土”的艰辛;读书,让我们感知到“四海无闲田,农夫犹饿死”的无奈;读书,让我们感悟到“为报倾城随太守,西北望射天狼”的豪情壮志。 读书的好处在于提高了生活的质量,它填补了我们人生中的空白,让我们不至于在大好的年华里无所事事,从书本中,我们学会提炼出有用的信息,汲取成长所需的营养。所以,我们要认真读书,充分认识到读书对改善生活的重要意义,只有这样,才是一种负责任的生活态度。 小学生个人读书事迹2 所谓读一本好书就是交一个良师益友,但我认为读一本好书就是一次大冒险,大探究。一次体会书的过程,真的很有意思,咯咯的笑声,总是从书香里散发;沉思的目光也总是从书本里透露。是书给了我启示,是书填补了我无聊的夜空,也是书带我遨游整个古今中外。所以人活着就不能没有书,只要爱书你就是一个爱生活的人,只要爱书你就是一个大写的人,只要爱书你就是一个懂得珍惜与否的人。可真所谓
关于坚持的英语演讲稿 Results are not important, but they can persist for many years as a commemoration of. Many years ago, as a result of habits and overeating formed one of obesity, as well as indicators of overall physical disorders, so that affects my work and life. In friends to encourage and supervise, the participated in the team Now considered to have been more than three years, neither the fine rain, regardless of winter heat, a day out with 5:00 time. The beginning, have been discouraged, suffering, and disappointment, but in the end of the urging of friends, to re-get up, stand on the playground. 成绩并不重要，但可以作为坚持多年晨跑的一个纪念。多年前，由于庸懒习惯和暴饮暴食，形成了一身的肥胖，以及体检指标的全盘失常，以致于影响到了我的工作和生活。在好友的鼓励和督促下，参加了晨跑队伍。现在算来，已经三年多了，无论天晴下雨，不管寒冬酷暑，每天五点准时起来出门晨跑。开始时，也曾气馁过、痛苦过、失望过，但最后都在好友们的催促下，重新爬起来，站到了操场上。 In fact, I did not build big, nor strong muscles, not a sport-born people. Over the past few years to adhere to it, because I have a team behind, the strength of a strongteam here, very grateful to our team, for a long time, we encourage each other, and with sweat, enjoying common health happy. For example, Friends of the several run in order to maintain order and unable to attend the 10，000 meters race, and they are always concerned about the brothers and promptly inform the place and time, gives us confidence and courage. At the same time, also came on their own inner desire and pursuit for a good health, who wrote many of their own log in order to refuel for their own, and inspiring. 其实我没有高大身材，也没健壮肌肉，天生不属于运动型的人。几年来能够坚持下来，因为我的背后有一个团队，有着强大团队的力量，在这里，非常感谢我们的晨跑队，长期以来，我们相互鼓励着，一起流汗，共同享受着健康带来的快
口语常用背诵素材 一，喜好和厌恶： 1.（释放压力）I guess most young people enjoy listening to music. It’s a perfect way to reduce stress/relieve stress. (*It’s a perfect stress-buster.) 2.（休闲）I think the best way to relax and kill time (kick back and relax) is to be with friends. Chatting with them helps me unwind/wind down (* Chatting with them is very therapeutic). 3.（放松）I found it pretty relaxing to flick through a magazine before going to bed (*before hitting the sack/hitting the hay). 4.（运动）Jogging on sunny days and simply basking in the sun(bathing in the sun) is super enjoyable(pleasurable). /Jogging is my favorite workout. It can always cheer me up after I’ve been down and depressed. And it can help me shed some unwanted weight. 5.（喜欢，提升心情）I’m quite into watching sitcom (I’m fascinated by, I’m crazy about, I adore, I’m very fond of...). Spending 20 minutes in front of the screen and having a good laugh after dinner really puts me in a better mood/ switch my mood/ lift my spirits. 6.（天气）I fancy spring most compared to the other three. Summer is simply too hot and stuffy (*muggy), and you can’t stay out for two minutes without getting sweaty and smelly. Autumn is too dry and winter too freezing cold. 7.（电影）I’m a movie buff (Movies are my biggest pastime), and I would either catch one on my couch or go to the movie theatre when they have the one I like on the big screen./ It's a great form of relaxation for me to while away the hours of a long flight, to keep my family together on the sofa, and to give me a bit of a thrill. 8.（无聊困难）I’m terrible at what I study now./(History is never my forte/ my strong suit). The classes are kind of a drag (It’s super dull/ *It’s mind-numbing), and there’s always loads of (tons of) homework to do. Memorizing those facts and years is a lot of effort (is tricky; is no picnic; is challenging for me). 9.（不能忍）I can’t stand (I hate, I totally dislike) the busy traffic in my city. I’m sick and tired of always getting stuck in traffic for a long time during rush hours. It really bothers me (It drives me crazy, *It drives me up the wall). 10. （受欢迎）Hip-hop is really trendy (is catching on, is all the rage) among young people these days. 二，时间和地点 11. （优点）What’s great about my home town is that there are plenty of shopping malls, coz I’m a shopaholic and I can shop for hours. 12. （远）The stadium is quite far away from where I live, and every time I want to do there, it takes me roughly 40 minutes by bus to arrive. (It’s one-hour drive from the city center.) 13. （方便）My apartment is in the center/heart of the city, a handy location where I can find supermarkets and clubs right on my doorstep. It’s a bit noisy though. 14. （近）I’m a movie-goer and and there’s a movie theater pretty close to my home, so I go there quite often (frequently). (close to my home= *within walking distance of my home , *in close proximity to my home) 15. （经常）I have a heavy workload at school, so I have to go to the library to study pretty much
1.How to build a business that lasts100years 0:11Imagine that you are a product designer.And you've designed a product,a new type of product,called the human immune system.You're pitching this product to a skeptical,strictly no-nonsense manager.Let's call him Bob.I think we all know at least one Bob,right?How would that go? 0:34Bob,I've got this incredible idea for a completely new type of personal health product.It's called the human immune system.I can see from your face that you're having some problems with this.Don't worry.I know it's very complicated.I don't want to take you through the gory details,I just want to tell you about some of the amazing features of this product.First of all,it cleverly uses redundancy by having millions of copies of each component--leukocytes,white blood cells--before they're actually needed,to create a massive buffer against the unexpected.And it cleverly leverages diversity by having not just leukocytes but B cells,T cells,natural killer cells,antibodies.The components don't really matter.The point is that together,this diversity of different approaches can cope with more or less anything that evolution has been able to throw up.And the design is completely modular.You have the surface barrier of the human skin,you have the very rapidly reacting innate immune system and then you have the highly targeted adaptive immune system.The point is,that if one system fails,another can take over,creating a virtually foolproof system. 1:54I can see I'm losing you,Bob,but stay with me,because here is the really killer feature.The product is completely adaptive.It's able to actually develop targeted antibodies to threats that it's never even met before.It actually also does this with incredible prudence,detecting and reacting to every tiny threat,and furthermore, remembering every previous threat,in case they are ever encountered again.What I'm pitching you today is actually not a stand-alone product.The product is embedded in the larger system of the human body,and it works in complete harmony with that system,to create this unprecedented level of biological protection.So Bob,just tell me honestly,what do you think of my product? 2:47And Bob may say something like,I sincerely appreciate the effort and passion that have gone into your presentation,blah blah blah-- 2:56(Laughter) 2:58But honestly,it's total nonsense.You seem to be saying that the key selling points of your product are that it is inefficient and complex.Didn't they teach you 80-20?And furthermore,you're saying that this product is siloed.It overreacts, makes things up as it goes along and is actually designed for somebody else's benefit. I'm sorry to break it to you,but I don't think this one is a winner.
关于工作的优秀英语演讲稿 Different people have various ambitions. Some want to be engineers or doctors in the future. Some want to be scientists or businessmen. Still some wish to be teachers or lawers when they grow up in the days to come. Unlike other people, I prefer to be a farmer. However, it is not easy to be a farmer for Iwill be looked upon by others. Anyway,what I am trying to do is to make great contributions to agriculture. It is well known that farming is the basic of the country. Above all, farming is not only a challenge but also a good opportunity for the young. We can also make a big profit by growing vegetables and food in a scientific way. Besides we can apply what we have learned in school to farming. Thus our countryside will become more and more properous. I believe that any man with knowledge can do whatever they can so long as this job can meet his or her interest. All the working position can provide him with a good chance to become a talent. 1 ————来源网络整理，仅供供参考
雅思口语素材 Document serial number【LGGKGB-LGG98YT-LGGT8CB-LGUT-
Useful Expressions: Words and phrases Friends and communication: solidify/ strengthen/ enhance/ promote communication / connection with mutual understanding relationship network/circle of f r i e n d s cultivate/develop friendship with s b . keep steady relationship with sb. establish interpersonal networksac build up the social circle spur message transmission Knowledge and experience widen one’s outlook broaden one’s vision/horizon acquire knowledge and skills comprehensive/overall quality
expand/enlarge one’s scope of knowledge knowledge reserve/base/storage theoretical knowledge practical skills social experience broaden one’s knowledge base promote one’s overall/ comprehensive competence accumulate experiences learn lessons from past experiences Work and experience the scarcity of employment o p p o r t u n i t i lay the foundations for career p r o s p e r i t y
个人先进事迹简介 01 在思想政治方面,xxxx同学积极向上,热爱祖国、热爱中国共产党,拥护中国共产党的领导.利用课余时间和党课机会认真学习政治理论,积极向党组织靠拢. 在学习上,xxxx同学认为只有把学习成绩确实提高才能为将来的实践打下扎实的基础,成为社会有用人才.学习努力、成绩优良. 在生活中,善于与人沟通,乐观向上,乐于助人.有健全的人格意识和良好的心理素质和从容、坦诚、乐观、快乐的生活态度,乐于帮助身边的同学,受到师生的好评. 02 xxx同学认真学习政治理论,积极上进,在校期间获得原院级三好生,和校级三好生,优秀团员称号,并获得三等奖学金. 在学习上遇到不理解的地方也常常向老师请教,还勇于向老师提出质疑.在完成自己学业的同时,能主动帮助其他同学解决学习上的难题,和其他同学共同探讨,共同进步. 在社会实践方面,xxxx同学参与了中国儿童文学精品“悦”读书系,插画绘制工作,xxxx同学在班中担任宣传委员,工作积极主动,认真负责,有较强的组织能力.能够在老师、班主任的指导下独立完成学院、班级布置的各项工作. 03 xxx同学在政治思想方面积极进取,严格要求自己.在学习方面刻苦努力,不断钻研,学习成绩优异,连续两年荣获国家励志奖学金；作
为一名学生干部,她总是充满激情的迎接并完成各项工作,荣获优秀团干部称号.在社会实践和志愿者活动中起到模范带头作用. 04 xxxx同学在思想方面,积极要求进步,为人诚实,尊敬师长.严格 要求自己.在大一期间就积极参加了党课初、高级班的学习,拥护中国共产党的领导,并积极向党组织靠拢. 在工作上,作为班中的学习委员,对待工作兢兢业业、尽职尽责 的完成班集体的各项工作任务.并在班级和系里能够起骨干带头作用.热心为同学服务,工作责任心强. 在学习上,学习目的明确、态度端正、刻苦努力,连续两学年在 班级的综合测评排名中获得第1.并荣获院级二等奖学金、三好生、优秀班干部、优秀团员等奖项. 在社会实践方面,积极参加学校和班级组织的各项政治活动,并 在志愿者活动中起到模范带头作用.积极锻炼身体.能够处理好学习与工作的关系,乐于助人,团结班中每一位同学,谦虚好学,受到师生的好评. 05 在思想方面,xxxx同学积极向上,热爱祖国、热爱中国共产党,拥护中国共产党的领导.作为一名共产党员时刻起到积极的带头作用,利用课余时间和党课机会认真学习政治理论. 在工作上,作为班中的团支部书记,xxxx同学积极策划组织各类 团活动,具有良好的组织能力. 在学习上,xxxx同学学习努力、成绩优良、并热心帮助在学习上有困难的同学,连续两年获得二等奖学金. 在生活中,善于与人沟通,乐观向上,乐于助人.有健全的人格意 识和良好的心理素质.
尊敬的领导，老师，亲爱的同学们， 大家好！我是5班的梁浩东。今天早上我坐车来学校的路上，我仔细观察了路上形形色色的人，有开着小车衣着精致的叔叔阿姨，有市场带着倦容的卖各种早点的阿姨，还有偶尔穿梭于人群中衣衫褴褛的乞丐。于是我问自己，十几年后我会成为怎样的自己，想成为社会成功人士还是碌碌无为的人呢，答案肯定是前者。那么十几年后我怎样才能如愿以偿呢，成为一个受人尊重，有价值的人呢？正如我今天演讲的题目是：自主管理。 大家都知道爱玩是我们孩子的天性，学习也是我们的责任和义务。要怎样处理好这些矛盾，提高自主管理呢？ 首先，我们要有小主人翁思想，自己做自己的主人，要认识到我们学习，生活这一切都是我们自己走自己的人生路，并不是为了报答父母，更不是为了敷衍老师。 我认为自主管理又可以理解为自我管理，在学习和生活中无处不在，比如通过老师，小组长来管理约束行为和同学们对自身行为的管理都属于自我管理。比如我们到一个旅游景点，看到一块大石头，有的同学特别兴奋，会想在上面刻上：某某某到此一游话。这时你就需要自我管理，你需要提醒自己，这样做会破坏景点，而且是一种素质低下的表现。你设想一下，如果别人家小孩去你家墙上乱涂乱画，你是何种感受。同样我们把自主管理放到学习上，在我们想偷懒，想逃避，想放弃的时候，我们可以通过自主管理来避免这些，通过他人或者自己的力量来完成。例如我会制定作息时间计划表，里面包括学习，运动，玩耍等内容的完成时间。那些学校学习尖子，他们学习好是智商高于我们吗，其实不然，在我所了解的哪些优秀的学霸传授经验里，就提到要能够自我管理，规范好学习时间的分分秒秒，只有辛勤的付出，才能取得优异成绩。 在现实生活中，无数成功人士告诉我们自主管理的重要性。十几年后我想成为一位优秀的，为国家多做贡献的人。亲爱的同学们，你们们？让我们从现在开始重视和执行自主管理，十几年后成为那个你想成为的人。 谢谢大家！