A knowledge portal is an integrated gateway for accessing relevant knowledge, collaborating and communicating with other users, and also linking internal applications which is becoming crucial in the age of information abundance. Research and development is a typical knowledge-intensive activity. However, knowledge management support in R&D has been minimal in most research organizations. In this paper, a knowledge portal is designed to support team-based researches in science and technology for searching and browsing knowledge, and also communicating with other team members, coordinating research project and collaborating with other researchers. Automating knowledge acquisition from various knowledge sources, knowledge categorization by applying text categorization method, and knowledge recommendation can help to relieve management effort and increase the efficiency of knowledge management processes. A prototype system based on the suggested model is also presented.