a b s t r a c tRapid melt pool formation and solidification during the metal powder bed process Selective Laser Melting (SLM) generates large thermal gradients that can in turn lead to increased residual stress formation within a component. Metal anchors or supports are required to be built in-situ and forcibly hold SLM structures in place and minimise geometric distortion/warpage as a result of this thermal residual stress. Anchors are often costly, difficult and time consuming to remove and limit the geometric freedom of this Additive Manufacturing (AM) process. A novel method known as Anchorless Selective Laser Melting (ASLM) maintains processed material within a stress relieved state throughout the duration of a build. As a result metal components formed using ASLM do not require support structures or anchors. ASLM locally melts two or more powdered materials that alloy under the action of the laser and can form into various combinations of eutectic/hypo/hyper eutectic alloys with a new lower solidification temperature. This new alloy is maintained in a semi-solid or stress reduced state throughout the build with the assistance of elevated powder bed pre-heating. In this paper the ASLM methodology is detailed and investigations into processing of a low temperature eutectic Al-Si binary casting alloy is explored. Two types of Al powders were compared; pre-alloyed AlSi12 and elemental mix Al + 12 wt% Si. The study established an understanding of the laser in-situ alloying process and confirmed successful alloy formation within the process. Differential thermal analysis, microscopy and X-Ray diffraction were used to further understand the nature of alloying within the process. Residual stress reduction was observed within ASLM processed elemental Al + Si12 and geometries produced without the requirement for anchors.
The formulation of moxifloxacin was found liquid at the formulated pH and formed gel in the presence of mono or divalent cations. The gel formed in situ showed sustained drug release over a period of 10-12 h. The formulations were less viscous before instillation and formed strong gel after instilling it into cul-de-sac. It is thus concluded that by adopting a systematic formulation approach, an optimum point can be reached in the shortest time with minimum efforts to achieve desirable rheological and in vitro release property for in situ gel forming system.
Ranitidine HCl matrix floating tablets were formulated to release 90% of drug in stomach within 12 h. Hence, release of the drug could be sustained within narrow absorption site. Moreover, the dosage form was found to be floating within a fraction of second independent of the pH of media ensuring a robust formulation.
Background: Bortezomib is reversible inhibitor of proteasome proteins for mammalian cells. Bortezomib is proven to be cytotoxic to a number of tumor cells by disrupting their normal homeostatic mechanism and thereby causing cell death. Currently, Bortezomib is prescribed for patients with multiple myeloma and mantle cell lymphoma. Objective: This assessment highlights the overview of recent patents of Bortezomib. This review includes patents grouped in sections like product patents, process patent, composition related patents as well as treatment methodology. Objective of this article is to facilitate researchers with all existing patents at single place. Methods: Data were searched from various online databases. In which, paid databases include SciFinder® and Orbit® . Free databases include Patentscope® (WIPO), Worldwide Espacenet® (EPO), Google Patents and InPASS (Indian patent database). Results: Several new processes and composition related patents of Bortezomib have been recently patented as its orangebook listed patents are going to soon expire during July 2022. Further, due to problem of oxidation during development and long-term storage of Bortezomib formulation, a number of excipients are tried in these patents to stabilize the same. However, there is still need for further development of improved formulation of Bortezomib with better characteristics. Conclusion: Extensive research have been carried out on various process for preparing Bortezomib and composition thereof. This type of dynamic research will clear the path for many generic players in the United States which lead in reduction of price of the composition and thereby enhancing global health care at cheaper prices.
Abstract:The additive manufacturing process Selective Laser Melting (SLM) can generate large thermal gradients during the processing of metallic powder; this can in turn lead to increased residual stress formation within a component. Metal anchors or support structures are required to be built during the process and forcibly hold SLM components to a substrate plate and minimise geometric distortion/warpage due to the process induced thermal residual stress. The requirement for support structures can limit the geometric freedom of the SLM process and increase post-processing operations. A novel method known as Anchorless Selective Laser Melting (ASLM) maintains processed material within a stress relieved state throughout the duration of a build. As a result, metal components formed using ASLM do not develop signification residual stresses within the process, thus, the conventional support structures or anchors used are not required to prevent geometric distortion. ASLM locally melts two or more compositionally distinct powdered materials that alloy under the action of the laser, forming into various combinations of hypo/hyper eutectic alloys with a new reduced solidification temperature. This new alloy is maintained in a semi-solid or stress reduced state for a prolonged period during the build with the assistance of elevated powder bed pre-heating. In this paper, custom blends of alloys are designed, manufactured and processed using ASLM. The purpose of this work is to create an Al339 alloy from compositionally distinct powder blends. The in-situ alloying of this material and ASLM processing conditions allowed components to be built in a stress-relieved state, enabling the manufacture of overhanging and unsupported features.
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