The present invention provides a method for recycling of the waste silicasand used in casting and for recycling of coal provided together with wastesilica sand. Waste silica sand may comprise dirt such as coal powder,...The present invention provides a method for recycling of the waste silicasand used in casting and for recycling of coal provided together with wastesilica sand. Waste silica sand may comprise dirt such as coal powder,bentonite and resin as a result of metal casting process. The recyclingmethod for waste casting sand can be applied manually or automatically,and in general, the method comprises a water alkalizing step to be usedin washing。展开更多
With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents ...With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents in the field of wireless charging by applying the adjusted ‘double-proportion'obsolescence method. The research reveals the rules of patent life span in the field of wireless charging,finding that the first 5 years since patents were authorized is the core period for the patents to play their full value,and also discovers the development law of merging technology patents.展开更多
文摘The present invention provides a method for recycling of the waste silicasand used in casting and for recycling of coal provided together with wastesilica sand. Waste silica sand may comprise dirt such as coal powder,bentonite and resin as a result of metal casting process. The recyclingmethod for waste casting sand can be applied manually or automatically,and in general, the method comprises a water alkalizing step to be usedin washing。
基金Supported by the National Social Science Foundation of China(No.12CTQ025)
文摘With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents in the field of wireless charging by applying the adjusted ‘double-proportion'obsolescence method. The research reveals the rules of patent life span in the field of wireless charging,finding that the first 5 years since patents were authorized is the core period for the patents to play their full value,and also discovers the development law of merging technology patents.
