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Kinetic studies were conducted on the carbon monoxide reduction of molybdenite in the presence of lime. Contrary to the expectation that the MoS 2 (s) ϩ CaO (s) ϩ CO (g) reaction will result in metal formation, molycarbide was found to form and no Mo was detected in the product. This is explained on the basis of thermochemical considerations, which indicate that the Mo 2 C formation is more feasible by eight orders of magnitude. The effects of quantity of lime in the charge, CO flow rate, temperature (1123 to 1298 K), and time of reduction have been studied. Kinetic analysis reveals that the results on the MoS 2 (s) conversion to Mo 2 C (s) fit into a modified parabolic rate law. Based on the thermochemical calculations and experimental findings, the probable reaction scheme has been identified. Molycarbide appears to form by a three-successive solid-gas reaction path consisting of (1) metal formation by the MoS 2 (s) ϩ CO (g) reaction followed by (2) in-situ carburization of Mo metal by CO (g), and finally (3) the scavenging of the COS (g) by lime, resulting in CaS (s). The latter two reactions drive the overall reaction forward. Further, out of these three consecutive reactions, progress of the overall MoS 2 ϩ CaO ϩ CO reaction seems to be governed by the intrinsic kinetics of the first one. Calcium molybdate, which forms as a transitory phase, plays a significant role by modifying the linear kinetics of the MoS 2 (s) ϩ CO (g) to one of parabolic nature.

It is practically impossible to avoid the nonspecific binding of protein to a nanocarrier when it enters a biological fluid. This hinders the chemotherapeutic efficacy of the nanocarrier to a large extent. Surface functionalization, in the recent past, helped in reducing such nonspecific interactions. However, there is a lack of understanding as to how they help in the case of nanocarriers with size <6 nm. Here, we show that the glutathione and folic acid functionalization to a small carbogenic nanocarrier leads to substantial improvement in cell internalization and chemotherapeutic efficacy. The functionalization on smaller size of the nanocarrier helped in manipulating the binding affinity of the protein, which in turn helped in easy dynamic exchange with the surrounding environment. Using fluorescence lifetime imaging, we directly visualized and mapped the released drug at a very high resolution and provide a comprehensive mechanism of the drug distribution inside a cancer cell, as a consequence of the different affinity of protein corona on the carbon nanoparticle.

A specific labeling strategy using carbon dots helped in the direct visualization of protein corona under TEM.

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