不是很全，但还是包括不少会议信息的网站：
http://www.allconferences.com/
AllConferences.Com
Is a directory focusing on conferences, conventions, trade shows, exhibits, workshops, events and business meetings. This is a unique search directory that serves users looking for specific information on conference or event information; while at the same time provides services to the meeting planners, such as online registrations and payment processing. We are dedicated to providing our end users with high-quality conference information with a comprehensive search engine. The information ranges from specialized scientific, medical and academic conferences to all kinds of general events.
我把化学会议单独挑出来：
Chemistry Conferences
http://www.allconferences.com/Science/Chemistry/
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