The Fe 3 O 4 nanoparticles is a promising material in a number of areas, but little is known on the effects of temperature on its properties. Therefore, Fe 3 O 4 nanoparticles was prepared by chemical co-precipitation method, the particle size, the spectra changes and the stabilities of Fe 3 O 4...

Impulsive control of a chaotic system is ideal for designing digital control schemes where the control laws are generated by digital devices which are discrete in time. In this paper, several new theorems on the stability of impulsive control systems are presented. These theorems are then used...

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. Among participants: the majority were women (74.7%)...

Non-targeted analysis (NTA) was used in identifying volatile organic compounds (VOCs) in a museum in China with the gas chromatograph (GC)−Orbitrap−mass spectrometer (MS). Approximately 230 VOCs were detected, of which 117 were observed at 100% frequency across all sampling sites. Although...

Based on the analogy between electricity and heat, we find that electric transformers and heat exchangers have many similarities. However, unlike transformers where Vo can be higher than Vi, the outlet temperatures of conventional heat exchangers are limited (i.e. Tc,o<Th,i, Th,o>Tc,i). Therefore, the...</th,i,>

This paper studies stationary oscillation for a time-varying recurrent cellular neural network with time delays and impulses. In a recent paper, the authors claim that they obtain a criterion of existence, uniqueness, and global exponential stability of periodic solution (i.e. stationary...