Characteristics and comparison of different radiofrequency-only multipole cooling cells

Various multipole cooling cells are widely used in mass spectrometry for their outstanding performance with regard to transmission and cooling effects. Among these, radiofrequency (RF)-only quadrupoles, hexapoles, and octopoles are routinely used in practical instrumentation. A study of their performance has been carried out using a house-built electrospray time-of-flight mass spectrometer equipped with three different multipole devices. In addition, a user-written program was developed using SIMION 7.0 to simulate ion transmission characteristics for the different devices utilized. Systematic experiments and simulations were performed with an RF-only quadrupole, hexapole, and octopole to study their theoretical and practical characteristics.     

Crystalline and active additive for optimization morphology and absorption of narrow bandgap polymer solar cells

The morphology of active layer with an interpenetrating network structure and appropriate phase separation is of great significance to improve the photovoltaic performance for polymer solar cells. A highly crystalline small molecule named DPP-TP6 was synthesized and incorporated into the narrow bandgap polymer solar cells to optimize the morphology of PTB7:PC₇₁BM active layer. The DPP-TP6 small molecule was demonstrated to enhance the light absorbance of active layer and play the role of energy cascade to increase the exciton separation and charge transfer. What's more, DPP-TP6 facilitated forming interpenetrating network structure and increasing the phase separation size of ternary blends. These phenomena lead to a higher hole mobility and a more balanced carrier mobility, so as to increase the power conversion efficiency to 7.85% at DPP-TP6 weight ratio of 8 wt %, comparing to the pristine PTB7:PC₇₁BM system of 6.50%. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 726–733     

Experimental performance analysis of two different passive cooling techniques for solar photovoltaic installations

Journal of Thermal Analysis and Calorimetry - At higher ambient temperatures during summer months, the cell temperature of a photovoltaic (PV) module increases to 50–60 °C and sometimes...     

Molecular structure matching by simulated annealing. I. A comparison between different cooling schedules

Summary This paper outlines an application of the theory of simulated annealing to molecular matching problems. Three cooling schedules are examined: linear, exponential and dynamic cooling. The objective function is the sum of the elements of the difference distance matrix between the two molecules generated by continual reordering of one molecule. Extensive tests of the algorithms have been performed on random coordinate data together with two related protein structures. Combinatorial problems, inherent in the assignment of atom correspondences, are effectively overcome by simulated annealing. The algorithms outlined here can readily optimize molecular matching problems with 150 atoms.     

Ultrasonic-based protein quantitation by (18) O-labeling: optimization and comparison between different procedures

Herein we report results regarding the optimization and comparison between different ultrasonic‐based procedures for protein quantitation by the direct ¹⁸O‐labeling approach. The labeling procedure was evaluated using different proteins, different ultrasonic devices and different reaction times: from 30 s to 10 min with the ultrasonic probe and from 30 s to 30 min with the sonoreactor. Variables such as the enzyme‐to‐protein ratio and protein concentration were also assessed. The results show that it is possible to accelerate the labeling reaction from 12 h to only 15 min with the sonoreactor without compromising the labeling efficiency. A larger variation in the double labeling yield was obtained among the different peptides, but the values for the smaller peptides are similar to the ones achieved with the classic methodology. These findings were further confirmed by labeling a complex protein mixture from human plasma. It was also found that the labeling reaction is affected by the sample concentration, even when performed with the classic overnight procedure. Copyright © 2010 John Wiley & Sons, Ltd.     

Comparison of configurations of a four-column simulated moving bed process by multi-objective optimization

Configurations of a four-column simulated moving bed chromatographic process are investigated by multi-objective optimization. Various existing column configurations are compared through a multi-objective optimization problem. Furthermore, an approach based on an SMB superstructure is applied to find novel configurations which have been found to outperform the standard SMB configuration. An efficient numerical optimization technique is applied to the mathematical model of the SMB process. It has been confirmed that although the optimal configuration highly depends on the purity requirement, the superstructure approach is able to find the most efficient configuration without exploring various existing configurations.     

Modeling,multi-objective optimization and comparison of fire and water tube heat recovery steam generators for gas engine cogeneration plants

Journal of Thermal Analysis and Calorimetry - An innovative modeling and optimizing of fire and water tube heat recovery steam generators (HRSG) for gas engine cogeneration plant are performed...     

Thermal performances of porous snow by a hydronic heating system at different weather conditions

Journal of Thermal Analysis and Calorimetry - The snow on the road in the cold regions is easy to cause slippery conditions, which are dangerous for vehicles and people. To remove the slippery...     

Determination of silver in fresh water by atomic absorption spectrometry following flotation preconcentration by iron(III) collectors

Colloid precipitate flotation of silver from fresh water is applied for preconcentration and separation. Optimal conditions using hydrated iron(III) oxide and iron(III) tetramethylenedithiocarbamate as collectors were investigated. Various factors affecting the silver recovery, including collector mass, nature of the supporting electrolyte, pH of the working medium, electrokinetic potential of the collector particle surfaces, type of surfactant, induction time etc., were checked. Within the optimal pH range (5.5–6.5) silver was separated quantitatively (94.9– 100.0%) with 30 mg Fe(III) as collector. The content of silver was determined by electrothermal atomic absorption spectrometry and compared to that from inductively coupled plasma-atomic emission spectrometry. The detection limit of silver by the method described is 0.01 μg/L.     

Thermal and economic modeling and optimization of solar-assisted underfloor heating system considering hourly analysis

Journal of Thermal Analysis and Calorimetry - In this paper, a new configuration for heating of the space based on solar energy is introduced. To have an efficient system as well as a space with...     

Numerical simulation and experimental investigation of air cooling system using thermoelectric cooling system

Journal of Thermal Analysis and Calorimetry - Efficient air-conditioning inside the cars is a challenge in automobile industry. Thermoelectric is one of the new methods for air cooling. It has many...     

High-temperature hydrogen production by solar thermochemical reactors,metal interfaces,and nanofluid cooling

Journal of Thermal Analysis and Calorimetry - Solar thermochemical reactors have been considered in recent studies because of converting the solar energy to a fuel, which is called solar fuel. In...     

Hydrogen absorption and desorption by the Li-Al-N-H system

Lithium hexahydridoaluminate Li(3)AlH(6) and lithium amide LiNH(2) with 1:2 molar ratio were mechanically milled, yielding a Li-Al-N-H system. LiNH(2) destabilized Li(3)AlH(6) during the dehydrogenation process of Li(3)AlH(6), because the dehydrogenation starting temperature of the Li-Al-N-H system was lower than that of Li(3)AlH(6). Temperature-programmed desorption scans of the Li-Al-N-H system indicated that a large amount of hydrogen (6.9 wt %) can be released between 370 and 773 K. After initial H(2) desorption, the H(2) absorption and the desorption capacities of the Li-Al-N-H system with a nano-Ni catalyst exhibited 3-4 wt % at 10-0.004 MPa and 473-573 K, while the capacities of the system without the catalyst were 1-2 wt %. The remarkably increased capacity was due to the fact that the kinetics was improved by addition of the nano-Ni catalyst.     

Thermal performance modeling of modified absorber wall of solar chimney-shaped channels system for building ventilation

Journal of Thermal Analysis and Calorimetry - This paper aims to compare the thermal performance of four different configurations of absorber wall for the solar chimney-shaped channels. A detailed...     

Thermal decomposition of lignocellulosic materials: comparison of the results obtained in different experimental systems

An experimental system that allows the use of large particle sizes and the simulation of different operating conditions was built to study the thermal decomposition of lignocellulosic materials. The values of solid conversion and of temperature obtained at different points using spherical particles of pine wood 2 cm in diameter are shown. The conversion values are compared with those calculated from the equations obtained in a thermobalance for small particle sizes.     

Enhanced efficiency and stability of perovskite solar cells by 2D perovskite vapor-assisted interface optimization

Organic–inorganic perovskites solar cells(PSCs)have attracted great attention due to their rapid progress in power conversion efficiency(PCE).However,there is still an enormous challenge to achieve both high efficiency and stability devices as the decomposition of perovskite materials under humid and light conditions.Herein,we demonstrate that high efficiency and stability of PSCs can be obtained by the reaction of three-dimensional(3D)perovskite with 1,4-butanediamine iodide(BEAI2)vapor.The incorporation of BEAI2 intensively promotes the crystallization of perovskite film with large grain size(~500 nm).Further characterization reveals that the post-treatment perovskite film delivered low interface trap density with long carrier lifetime(>200 ns),long carrier diffusion length(>600 nm)and large carrier mobility(>1.5 cm^2 V-1S-1).Solar cells employing such post-treatment films demonstrated 19.58%PCE without hysteresis.Moreover,the post-treatment devices can retain over 90%original efficiencies stored under ambient atmospheric conditions and exhibit better stability under 85℃and continuous illumination as a two-dimensional(2D)perovskite thin layer is formed on the surface/or at the grain boundaries of 3D perovskite.This study offers an effective way to obtain PSCs with high efficiency and stability.     

Further development and optimization of a quartz tube atomizer for a gas chromatography — atomic absorption spectrometer system

A new quartz T-tube furnace design based on commercial heater modules was evaluated for the determination of organolead and organotin compounds. Furnace operating conditions for both packed and capillary column operation were optimized by multivariate analysis. Response reproducibility ranged from 1.8 to 3.9% relative standard deviation. Calculated limits of detection were 1.4–2.0 pg for Et₄Pb (as Pb) and 2.2–5.5 pg for Bu₄Sn (as Sn). The limits of detection after application of Savitsky-Golay smoothing were 1.1–1.2 pg for Et₄Pb (as Pb) and 2–3.7 pg for Bu₄Sn (as Sn).