- 252020-03
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Environmental protection sewage treatment field
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- 252020-03
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Fire protection field
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- 252020-03
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Chemical industry and petroleum industry
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- 252020-03
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Water power and electric power
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- 252020-03
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Urban water supply
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- 252020-03
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Farmland, water power, drainage and irrigation
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- 252020-03
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Construction, municipal and engineering fields
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- 252020-03
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Industry and communication
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- 252020-03
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Medicine and juice
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