【文章內(nèi)容簡介】 . I will start with an Introduction, then explain the experimental techniques, next present the most important results, and finally I hope to draw a few conclusions and I want to acknowledge a few people. So let us start with the Introduction …”If you open this way you will find yourself in the pany of many others. Nevertheless, this is a totally inefficient way to start a lecture. How would you respond if you were in the audience? In the opening, . the first few sentences, you catch the attention, for example by a scientific question, or a catchy or maybe even provocative statement. Perhaps you could already give the conclusion of your work too. Try to speak slowly, with emphasis, and look at the audience. Of course, you must have prepared and rehearsed the opening carefully.However, before you give your opening sentence, it is good to start with “Mister Chairman, Ladies and Gentlemen … ” followed by a few seconds of silence, in which you look around to see if people are paying attention. By doing so, you actually force the audience to listen. With these words you also test the sound system, and you ascertain that your important opening lines are going to be heard. In the rest of the Introduction, you sketch the background of your research. Remember that many people will be very interested in a concise summary of the status in your area. Hence, reserve sufficient time (. at least 30% of the total time) for the general aspects of your work. It is good practice to not only clearly identify the scientific question you address, but also give the conclusion of your work, if you wish so. In this way you enable the audience to better follow your reasoning and to anticipate on the oute of the experiments. In other words, you give them a chance to listen actively. Remember that a scientific presentation is not a detective story which is solved in the last moment. 5) Conclusions and EndingConclusions should be properly announced to regain full attention. Present your conclusions in relation to the questions you raised in the Introduction. Avoid all irrelevant details. Once you finished the conclusions, you may acknowledge people who helped you (not the coauthors listed in the program) and the Funding Agencies. Then you may end with a final sentence that repeats the message of your talk, for instance: “Ladies and Gentlemen, I hope I have convinced you that XY/Support is a very promising catalyst for converting methane into synthetic gasoline at room temperature.” This is the takehome message that the audience should remember, hopefully in bination with your name and affiliation.Figure 4 Spreadsheets often produce unsatisfactory figures, particularly with respect to labeling. A good figure has labels on the curves and not in a legend. Secret codes and jargon should be avoided as much as possible6) Excellent figures have the highest impactA picture is worth a thousand words. Well, not necessarily. Figures, especially those generated by spreadsheets, may look neat and tidy but at the same time they may be real puzzles (see Figure 4).A good picture to be used in an oral presentation is easy to read (large lettering, good contrast), explains itself (clear title, preferably a conclusion too) contains only relevant information, does not contain jargon or difficult codes that the audience needs to translate.Hence, when showing a series of spectra or activity curves, you put an understandable label on each curve (not a,b,c, which are explained in a separate legend!!). Avoid reference to samples in codes such as “Sample AX234/a5” which may be handy in laboratory notebooks, but are unsuitable in presentations (and in articles as well). Using tables with numbers is in most cases not remended. Remember that an audience reads everything you show on a transparency, and while they read they pay less attention to what you say. Also avoid theoretical formulas and mathematical derivations. Sometimes you may have to show one, but try to keep it to a minimum. You should realize that the human memory remembers in terms of pictorial information. Hence clear figures, schemes, and diagrams are the best means to convey information. 7) Visual Aids: Overhead Transparencies, Slides, or Computer Projection?Using transparencies on a simple overhead projector is more or less problem free. In most cases, transparencies project well, are easy to read for the audience, and the lecture hall does not have to be darkened so that people can make notes if they wish. For you as a speaker, transparencies leave you the flexibility to make last minute changes, or even write on them during projection.Tips for effective transparencies Preferably use landscape format Use large lettering Black letters on a white background, or bright yellow on black or dark blue give the best result Do not use structured backgrounds and do not waste too useful space on logos, etc. Use pictures, figures, with a title, a short, clear caption Avoid data in tables or in text If you use text than no more than 812 lines per slide Avoid plete sentences, use “headlines” Give each slide a title and try to include a brief conclusion at the bottom of each slide Remove all information from figures that is not absolutely necessary, but do provide clear understandable labels on curves and spectra, so that they bee self explanatory to the audience.Slides do not give this kind of flexibility. Optimally prepared slides in bination with a high quality projector can certainly provide beautiful visual support to your talk. Unfortunately, many slide projectors offer less than optimum quality, and moreover, many speakers show unsatisfactory slides. In addition, many things may go wrong: slide carrousels may get stuck, slides may go upside down, the slide control does not work properly, etc. Another serious drawback of using slides is that the lecture