Performance of cooling materials and their composites in maintaining freezing temperature during irradiation and transportation of bone allografts by Ramalingam, Saravana, Samsuddin, Sharifah Mazni, Yusof, Norimah, Mohd, Suhaili, Hanafi, Nurhafizatul Nadia, Ng, Wuey Min, Mansor, Azura