Hydrate formation apparatus reported so far was mainly concentrated in stirred-tank batch environments. It was difficult to produce the high gas storage hydrate efficiently. Some nonstirred technology has been attracting more attention by researchers. This work proposed a new apparatus for hydrate formation by spraying water into a gaseous phase with a fine nozzle. It can get sufficient contact surface area for gas-liquid reaction. Methane hydrate formation experiments have been conducted using pure water and sodium dodecyl sulfate (SDS) aqueous solution for comparison at 277.15 K. The experiments were conducted at 7.0 and 6.0 MPa, respectively. Kinetics of methane hydrate formation have been investigated by methane consumption per mole of water and reaction rate. The mechanism of hydrate formation and kinetics property by spraying atomization were studied with the theory of crystal chemistry.

No abstract

In this paper, the profile of the bar is detected by laser vision technology. During the detection process, obvious isolated outliers can be observed in the profile data; dimension parameter and profile-fitting accuracy are seriously affected by these outliers. In order to eliminate these outliers and improve the measurement accuracy, this paper uses Hampel identifier and moving mean identifier to identify isolated outliers. At the same time, the profile data is fitted, and the fitting results and fitting accuracy were analyzed and compared between the original data and the renovated data. The experiment proves that the outliers in the data must be identified and processed in the data measurement process. The Hampel identifier has better recognition effect, its algorithm is simple, efficient, and robust, and it can play an important role in the preprocessing of profile data based on structured light.

In this paper, an investigation is reported on graphene platelet (GPL)/nickel (Ni) laminate coatings by electrochemical deposition. Nickel sulphamate baths with and without GPLs are used to produce GPL/Ni coatings with varied layers and pure Ni coatings for comparison. Microstructures, surface roughness, and mechanical performance of the coatings were examined. It is found that GPLs are homogeneously deposited in the Ni matrix. With the addition of GPLs, the surface roughness of the GPL/Ni composites increases while the average grain size of the Ni matrix decreases significantly. A higher hardness of coatings can be obtained by depositing more layers and introducing a higher content of GPLs. The microstructure of GPL/Ni composite coatings exhibits a preferred orientation at (111).

No abstract