42 Engineering services in the field of cement manufacturing; Engineering services in the field of manufacturing calcium carbonate polymorphs, namely, vaterite, aragonite, and calcite; engineering services in the field of manufacturing lightweight cement or cementitious materials or aerated concrete; industrial and scientific research in the field of cement manufacturing; industrial and scientific research in the field of manufacturing calcium carbonate polymorphs, namely, vaterite, aragonite, and calcite; industrial and scientific research in the field of manufacturing lightweight cement or cementitious materials or aerated concrete; scientific consulting services in the field of cement manufacturing; scientific consulting services in the field of manufacturing calcium carbonate polymorphs, namely, vaterite, aragonite, and calcite; scientific consulting services in the field of manufacturing lightweight cement or cementitious materials or aerated concrete