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Author(s): Liangshu Zhong (corresponding author) [1]; Fei Yu [1, 2]; Yunlei An [1, 2]; Yonghui Zhao [1]; Yuhan Sun (corresponding author) [1, 3]; Zhengjia Li [1, 4]; Tiejun Lin [1]; [...]

Introducing promoters to cobalt-based catalysts for Fischer–Tropsch synthesis (FTS) has been found to be efficient in adjusting their performance in converting syngas into long-chain hydrocarbons. High spatial proximity of the promoter and reactive metal is desired to maximize the effectiveness of the promoters. In this work, CoMn@C composites were synthesized by the one-step carbonization of bimetal–organic frameworks (BMOFs: CoMn-BTC). BMOF-derived catalysts naturally exhibited that cobalt nanoparticles (NPs) are confined in the carbon matrix, with a concentrated particle size distribution around 13.0 nm and configurated with MnO highly dispersed throughout the catalyst particles. Mn species preferentially bind to the surfaces of Co NPs rather than embedded into the Co lattice. The number of Mn–Co interfaces on the catalyst surface results in the weakened adsorption of H but enhanced adsorption strength of CO and C. Hence, the incorporation of Mn significantly inhibits the production of CH4 and C2–C4 paraffin boosts light olefin (C2–4=) and C5+ production. Furthermore, the FTS activity observed for the Mn-promoted catalysts increases with increased Mn loading and peaks at 2Co1Mn@C due to the abundance of Co–Mn interfaces. These prominent FTS catalytic properties highlight the concept of synthesizing BMOF-derived mixed metal oxides with close contact between promoters and reactive metals. [ABSTRACT FROM AUTHOR]

It is of great significance to implement automatic demand response (ADR) in the energy Internet based on accurate measurement and control of electricity utilization devices using intelligent terminals. Current intelligent terminals lack flexibility and possess weak data collection and processing capabilities. On this basis, this paper developed an intelligent split-type electricity utilization measurement and control terminal for local household energy management and optimization. This intelligent terminal has capabilities of digital signal processing and infrared-based precision control, which is composed of two separate parts: the device body and the infrared controller. Among them, the device body includes DSP chip, electrical sampling circuit, ADC chip, WiFi module, ZigBee module, etc. The infrared controller contains single-chip microcomputer, ZigBee module, infrared encoding and transmit-receiving module, and lithium-ion battery. The device body is able to provide commands to the infrared controller according to the collected electricity utilization information, environmental information and comprehensive demand response requirements, thereby accurately adjusting the operating status of the loads, namely the electrical household appliances. Due to the split-type and rechargeable design, this intelligent terminal is able to adapt to a complex home environment, laying the hardware foundation for effective home energy management and optimization and facilitating household loads participating in demand response, especially automatic demand response.

In order to facilitate the active identification capability of various types of electrical equipment, so as to enhance the functions such as the behavioural analysis and optimization control of electricity utilization in an automatic demand side management (DSM) system. A definition is given on load fingerprint based on operating characteristics of household appliances, as well as its architecture. In addition, based on the cyber-physical systems (CPS) technology, a hierarchical technical framework for load fingerprint management is proposed. This framework is a two-layer electricity utilization load fingerprint management platform, including local management and cloud-based management. Finally, two hardware prototypes are developed, including a socket-type smart collection terminal and an intelligent interactive concentrator with multiple communication technologies, which can provide strong hardware support for the realization of the hierarchical technical framework proposed in this paper.

A series of Co/ SiO2 catalysts with different sodium (Na) loadings (0, 0.1, 0.2, 0.5 and 1 wt%) were prepared and evaluated for Fischer-Tropsch reaction to study the effect of Na on the catalyst structure and catalytic performance. The addition of Na was found to decrease the catalytic activity and hydrocarbon selectivity, but increase CO2 selectivity due to the enhanced WGS activity. The addition of Na also resulted in higher selectivity to oxygenates (alcohols and aldehydes) and O/P ratio as well as the shift of hydrocarbons to lower carbon numbers. Structure characterization revealed a decrease in the surface area and particles size for the calcined samples with the addition of Na. Co2C was formed during the reaction process for the Na-promoted catalysts. As a result, a new Co/ Co2C bifunctional active sites were generated for oxygenates formation leading to increasing oxygenates selectivity. In addition, the Co2C nanoparticles alone may also act as dual active sites for oxygenate formation at high reaction pressure over the promoted catalysts with high Na loading. [ABSTRACT FROM AUTHOR]

To clarify the role of a natural or artificial liquid environment in the free-running infrared pulsed laser ablation of hard biological tissues, two- and three-dimensional morphologies of laser-induced craters must be quantitatively measured to distinguish ablation differences in air and in water. Full-field optical coherence microscopy is introduced, which has non-contact, non-destructive, non-preprocessing and higher-resolution advantages. Experimental results indicate that the ablation performances in air and in water are comparable for few laser pulses, but the ablation difference becomes obvious for more laser pulses. Optical coherence microscopy is more feasible than conventional means for the morphological measurement of craters. [ABSTRACT FROM AUTHOR]

It is demonstrated that an asymmetric Fabry–Pérot fiber-optic pressure sensor is capable to precisely measure liquid levels. They are directly proportional to pressures that can modulate cavity length of Fabry–Pérot cavity. As a result, the sensor can operate over a linear region of an interference fringe that enables liquid-levels interrogation by measuring the reflected intensity. Experimental results show the resolving power of 0.4 mm, sensitivity of 2.4 mV/mm, and precision of 1 mm over range of 2.3 m (water) can be achieved. The sensor can measure liquid levels accurately, continuously, and automatically in flammable and explosive circumstances. [ABSTRACT FROM AUTHOR]

The major challenge in the production of xylene from benzene alkylation with methanol is to avoid the side reaction of methanol with olefins, and this leads to the low utilization efficiency of methanol and the generation of byproduct ethylbenzene. Hierarchical porous Ti-ZSM-5 with appropriate acidity was achieved by substituting part of Al by Ti in the synthesis process, which exhibited the high utilization efficiency of methanol and high suppression of the ethylbenzene formation by the efficient suppression of methanol to olefins. [ABSTRACT FROM AUTHOR]

This study clarifies the ablation differences in air and in water for hard biological tissues, which are irradiated by fiber-guided long-pulsed holmium lasers. High-speed photography is used to record the dynamic characteristics of ablation plumes and vaporization bubbles induced by pulsed holmium lasers. The ablation morphologies and depth of hard tissues are quantitatively measured by optical coherence microscopy. Explosive vaporization effects in water play a positive role in the contact ablation process and are directly responsible for significant ablation enhancement. Furthermore, water layer depth can also contribute to ablation performance. Under the same laser parameters for fiber-tissue contact ablation in air and water, ablation performances are comparable for a single-laser pulse, but for more laser pulses the ablation performances in water are better than those in air. Comprehensive knowledge of ablation differences under various environments is important, especially in medical procedures that are performed in a liquid environment.

To overcome the inconsecutive drawback of shadow and schlieren photography, the complete dynamics of cavitation bubble oscillation or ablation products induced by a single holmium laser pulse [2.12 microm, 300 micros (FWHM)] transmitted in different core diameter (200, 400, and 600 microm) fibers is recorded by means of high-speed photography. Consecutive images from high-speed cameras can stand for the true and complete process of laser-water or laser-tissue interaction. Both laser pulse energy and fiber diameter determine cavitation bubble size, which further determines acoustic transient amplitudes. Based on the pictures taken by high-speed camera and scanned by an optical coherent microscopy (OCM) system, it is easily seen that the liquid layer at the distal end of the fiber plays an important role during the process of laser-tissue interaction, which can increase ablation efficiency, decrease heat side effects, and reduce cost.

Low intensity irradiation of cells by laser was an effective method of biostimulation. Here, we have extended these actions to evaluate the apoptosis effects in red light emitting diode (RLED) exposure. Through morphological observation, flow cytometric analysis, intracellular calcium measurement and RT-PCR, we found that HeLa cells in 24 h RLED irradiation in in-vitro experiments would significantly affects the induction of cellular apoptosis, and morphological changes such as the loose arrangement of cells, the noticeable development of apoptotic bodies,and the accompaniment of arrested S phase and activated caspases-3,-6,-8. Moreover, intracellular calcium concentrations markedly increased 40.3 +/- 1.3% and 43.1 +/- 0.8% respectively, relative to an extracellular solution containing the Ca(2+) and Ca(2+) free unexposed group. In in-vivo tests, RLED irradiation decreased the growth of tumors on day 50 and attenuated the elevation of vascular endothelial growth factor (VEGF) expression in HeLa cell implanted BALB/c mice. Taken together, our results suggest that RLED could induce HeLa cell apoptosis and convey potential antitumor properties.