ABSTRACT
The quality of fresh foods tends to deteriorate rapidly during harvesting, storage, and transportation. Intelligent detection equipment is designed to monitor and ensure product quality in the supply chain, measure appropriate food quality parameters in real time, and thus minimize quality degradation and potential financial losses. Through various available tracking devices, consumers can obtain actionable information about fresh food products. This paper reviews the recent progress in intelligent detection equipment for sensing the quality deterioration of fresh foods, including computer vision equipment, electronic nose, smart colorimetric films, hyperspectral imaging (HSI), near-infrared spectroscopy (NIR), nuclear magnetic resonance (NMR), ultrasonic non-destructive testing, and intelligent tracing equipment. These devices offer the advantages of high speed, non-destructive operation, precision, and high sensitivity.
ABSTRACT
High-pressure multistage centrifugal pumps have been widely used in modern industry and required low vibration and noise. In this study, modal analysis of the rotor system of a seven-stage centrifugal pump was carried out numerically by introducing fluid force to ensure that the centrifugal pump would not resonate. A vibration test bench was established to investigate the characteristics with flow rates of 0.8Qd, 1.0Qd, and 1.2Qd, and the vibration data of ten measuring points were collected. The period of the vibration at the bearing was found to be around 20 ms and the period was related to the shaft frequency (SF) and the blade passing frequency (BPF). The vibration of the pump casing was mainly determined by the SF, two times the SF, and two times the BPF. Mechanical motion is the main factor causing pump vibration, and fluid unstable motion is also an important cause.
ABSTRACT
Two-dimensional Bi2Se3 nanosheets with hexagonal shape are synthesized by a solution synthetic route. The Bi2Se3 nanosheets are 120 nm in edge width and 7 nm in thickness. The size of the Bi2Se3 nanosheets can be controlled by choosing different kinds of reducing agents including hydroxylamine and ethylenediamine. Subsequently, we demonstrate a configuration of two-color all-optical switching based on plasma channels effect using the as-synthesized Bi2Se3 nanosheets as an optical media. The signal light can be modulated as two states including dot and ring shape by changing the intensity of control light. The modulated signal light exhibits excellent spatial propagation properties. As a type of interesting optical material, ultrathin two-dimensional Bi2Se3 nanosheets might provide an effective option for photoelectric applications.
ABSTRACT
This study aimed to develop novel galactosylated cholesterol modified-glycol chitosan (Gal-CHGC) micelles for targeting delivery of doxorubicin (DOX) in live cancer cells. Three kinds of Gal-CHGC conjugates were synthesized and characterized. The mean particle size and critical aggregation concentration of these polymeric micelles increased with the increase of galactose substitution degree. The DOX-loaded micelles were prepared by an o/w method. The mean diameters of DOX-loaded galactosylated micelles were in the range of 387-497 nm. DOX released from drug-loaded micelles displayed a biphasic way. Cellular uptake studies demonstrated that DOX-loaded galactosylated micelles could enhance the uptake of DOX into HepG2 cells. Moreover, the cytotoxicity of DOX-loaded galactosylated micelles against HepG2 cells significantly improved in contrast with free DOX and DOX-loaded micelles without galactosylation. These results suggested that Gal-CHGC micelles could be a potential carrier for hepatoma-targeting drug delivery.
Subject(s)
Cell Survival/drug effects , Chitosan/chemistry , Delayed-Action Preparations/chemical synthesis , Doxorubicin/administration & dosage , Doxorubicin/pharmacokinetics , Galactose/chemistry , Nanocapsules/chemistry , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/chemistry , Delayed-Action Preparations/administration & dosage , Doxorubicin/chemistry , Feasibility Studies , Hep G2 Cells , Humans , Materials Testing , Micelles , Nanocapsules/ultrastructure , Particle SizeABSTRACT
Surface plasmon polaritons (SPPs) Bragg reflector with more excellent optical properties are investigated numerically. By introducing a finite array of periodic grooves on the two surfaces of metal-insulator-metal (MIM) waveguide, we fulfill the periodical changes of effective refractive index, which leads to the photonic band gap (PBG). And it has been further widened by inserting a dielectric material with higher refractive index in the waveguide with narrow slit width. Finite difference time domain (FDTD) simulation confirms the widened bandgap. In addition, a SPP nanocavity is introduced by breaking the periodicity of our proposed structure.
