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Owing to their high cooling efficiency in summer and frost-free characteristics in winter, heating tower heat pumps are becoming increasingly popular. However, the solution will be diluted during heating due to absorbing moisture from the air, and should be properly regenerated for continuous operation. In this study, a novel heat recovery solution regeneration system using an internally heated regenerator is proposed for antifreeze solution regeneration. A test bench is fabricated to investigate the regeneration performance of the internally heated regenerator. Correlations of the heat and mass transfer coefficients are proposed, and agree well with the experimental data. The influences of inlet parameters on the moisture removal rate, latent heat ratio, and humidity effectiveness are evaluated and compared to those for internally heated liquid desiccant regeneration. The results indicate that: the regeneration performance of the internally heated regenerator is affected mainly by the air flow rate, heating water flow rate, and inlet temperature of heating water. The moisture removal rate increases remarkably with increasing the heating water flow rate and inlet temperature of heating water. The latent heat ratio decreases significantly with increasing the inlet temperature of heating water. The humidity effectiveness decreases remarkably with increasing the air flow rate. The influences of the above inlet parameters on performance indices in the present study exhibit the same trends as those reported for internally heated liquid desiccant regeneration. However, compared with internally heated liquid desiccant regeneration, the regeneration temperature for internally heated antifreeze solution regeneration is much lower. This suggests that a low-grade heat source can be used to meet the antifreeze solution regeneration demands.

Cross sections of the 144 Sm(n,α)141 Nd and 66 Zn(n,α)63 Ni reactions were measured at En = 4.0, 5.0 and 6.0 MeV performed at the 4.5-MV Van de Graaff Accelerator of Peking University, China. A double-section gridded ionization chamber was used to detect the alpha particles. The foil samples of 144 Sm2 O3 and enriched 66 Zn were placed at the common cathode plate of the chamber. Monoenergetic neutrons were produced by a deuterium gas target through the 2 H(d,n)3 He reaction. The neutron flux was monitored by a BF3 long counter. Cross sections of the 238 U(n,f) reaction were used as the standard to perform the (n,α) reaction measurement. Present results are compared with existing measurements and evaluations. They are generally in agreement with TALYS-1.6 code calculations. For the 144 Sm(n,α)141 Nd reaction our measurements support the data of JEF-2.2. For the 66 Zn(n,α)63 Ni reaction present results support the data of EAF-2010 and TENDL-2015 data.

Optocoupler is fabricated by applying two separated devices as its two important composition units, the photoemitter (input) and photosensor (output), and then combining them together. It is difficult to realize precise pixel-to-pixel alignment when the active area becomes smaller and smaller, which is a limitation in the microelectronics applications. Based on a double-side indium tin oxide (ITO) substrate, a highly integrable organic optocoupler (OOC) was developed. It can reduce the limitations mentioned above of traditional optocouplers. The current transfer ratio can be enhanced to the maximum 1.87% by changing the light-emitting area. In addition, the isolation voltage can also be improved to over 3000 V by the patterning lithography treatment to ITO substrate. This sort of OOC has a promising application in the micromation of electronic devices and can be also used in low-voltage-control circuits.

Improvement of electron injection is essential for highly efficient low-voltage organic light-emitting diodes (OLEDs). In this work, we report our study on thermally decomposable Li3N as the electron injection layer (EIL) for OLEDs. We use a quartz crystal microbalance method to investigate the decomposition process of Li3N during vacuum thermal evaporation in situ. Thermodynamics study also proves that Li3N decomposes in vacuum to form metallic lithium and nitrogen. OLEDs with Li3N as the EIL outperform those with conventional LiF in every respect of view. An optimized green OLED with a Li3N EIL shows 35% higher efficiency and more than doubled lifetime compared with the control device with a LiF EIL.

We demonstrate high performance blue, yellow and tandem white organic light-emitting diodes with low driving voltages using a novel electron transporting material. The blue and yellow OLEDs achieve low turn-on voltage of 2.6 V and 2.2V, respectively, equivalent to their energy gaps. The tandem white OLED shows an extremely low driving voltage of 5.9 V at 1000 cd/m2, together with an efficacy of 28.6 lm/W, a current efficiency of 53.7 cd/A, and an external quantum efficiency of 24.6%. A 64 × 64 mm2 panel has been produced with the same architectures as the tandem OLED pixel, the efficiency is further improved to 45 lm/W with the use of a micro-lens film.

The low carbon alloy steel was single face treated by a special hot diffusion method, and thus the gradual composite steel was produced. The microstructures of composite steel were very different from the matrix steel, white layer speared near the treated surface, and nano- and sub-micron particles were existed in the white layer. The results of ramon spectrum test indicated that the nano- and sub-micron particles can transfer several millimeters, several centimeters or even more. The mechanical properties changed sharply compared with the matrix steel. The hardness and the tensile strength near the treated surface were much higher than the matrix steel, and decreased gradually with the increase of distance to the treated surface. The composite steel has high strength, high hardness, high wear-resistance, high corrosion-resistance and etc. From the engineering application point of view, this technique can be used to produce super high qualities alloy steels, which can be used to the field as: metallurgy, mine, automobile, manufacture, energy sources, and etc.Copyright © 2006 by ASME

Tandem organic light emitting diodes (OLEDs) are ideal for lighting applications due to their low working current density at high brightness. In this work, we have studied an efficient electron transporting layer of KBH(4) doped 9,10-bis(3-(pyridin-3-yl)phenyl)anthracene (DPyPA) which is located adjacent to charge generation layer of MoO(3)/NPB. The excellent transporting property of the DPyPA:KBH(4) layer helps the tandem OLED to achieve a lower voltage than the tandem device with the widely used tris-(8-hydroxyquinoline)aluminum:Li. For the tandem white OLED with a fluorescent blue unit and a phosphorescent yellow unit, we've achieved a high current efficiency of 75 cd/A, which can be further improved to 120 cd/A by attaching a diffuser layer.

Ideal n-type layers are highly desired for high performance organic light emitting diodes (OLEDs). For the first time, we studied the combination of a low-temperature-evaporable n-dopant KBH₄ and a high mobility electron transport material 9,10-bis(3-(pyridin-3-yl)phenyl)anthracene (DPyPA). The excellent transporting property of the DPyPA: KBH₄ layer allows the fine tuning of the OLED performance by varying the thickness of the n-doped layer in a wide range (from 10 nm to 50 nm, 100 nm, 150 nm and 200 nm). The device with the optimized n-type layer thickness of 150 nm shows the best performance with a high current efficiency of 27.60 cd/A at the brightness 10,000 cd/m², which is about 40% higher than the device with a 10 nm n-type layer (19.95 cd/A at 10,000 cd/m²). The high performance is attributed to the optimization of optical path and the decrease of the loss in the organic layer/cathode interface due to the thick n-doped layer.

Based on analyzing the induced signals from the double-grids of an ionization chamber, the electron-drift time between the two grids is determined and the electron-drift velocity is derived. A waveform digitizer is employed to record pulses from the two grids of the ionization chamber. The electron-drift velocity is measured as a function of the reduced electric field E/p for eight different ratios of Ar+CH4 mixtures. By analyzing the experimental data of this study, self-consistency of experimental data is achieved, and formulae for calculating electron-drift velocity in any ratio of Ar+CH4 mixtures are obtained.

In this work, KBH4 was studied as a novel electron injection material (EIM) for organic light-emitting diodes (OLEDs). Optimized OLEDs using KBH4 as the EIM showed a high efficiency of 11.0 cd/A at 1000 cd/m2, comparable to that of a control device using LiF (9.2 cd/A). The lifetime of the device with KBH4 was also comparable to that of the control device. Thermal evaporation behavior was studied by thermodynamic calculation and X-ray photoemission spectroscopy (XPS), demonstrating that the improved electron injection was attributable to the low-work-function metallic K released by the thermal decomposition of KBH4.

Lithium cobalt oxide was introduced into organic light-emitting diodes as the electron injection layer. The device with tris(8-hydroxyquinolato) aluminum doped with 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one as the light-emitting layer and LiCoO2 as the electron injection layer showed promising efficiency (10.74cd∕A at 11V) and longer lifetime (2.8 times as much as LiF∕Al control device). Lithium cobalt oxide proved to be thermally decomposed in vacuum to form lithium oxide, which was responsible for the enhanced electron injection.