General projects: technical services, technical development, technical advice, technology exchange, technology transfer, technology promotion; engineering management services; specialized equipment for environmental protection; production of water quality pollutant monitoring and detection instruments; sale of pollution monitoring and detection instrument forms; water pollution prevention and treatment services; sewage treatment and reuse; production of air pollution monitoring and detection instrumentation; sale of specialized equipment for environmental protection; decoration, water heating and other construction metal production; distribution of plumbing equipment; retailing of hardware and equipment; production of hardware products; import and export of goods; import and export of technology; export and import of equipment; self-employment of import and export agents (except for projects authorized by law)