生物质液体燃料的制造

用生物质制造液体燃料是生物质能开发利用的重要课题,本文描述了近年公告的这方面国外专利技术。     

Effect of oxygen concentration in gas phase on sporulation and individual ganoderic acids accumulation in liquid static culture of Ganoderma lucidum

Effects of oxygen concentration within 21–100% in gaseous phase on the morphology and ganoderic acids (GAs) production by Ganoderma lucidum in liquid static culture were studied. A higher oxygen concentration increased individual GAs production, and more spores and higher total GA content were obtained at an oxygen level of 80%.     

用反相高效液相色谱法测定香兰素含量

研究采用反相高效液相色谱法测定香兰素含量,色谱柱为C18柱,乙腈/水(85/15,V/V)为流动相,等浓度洗脱,测定波长为279nm,内标法定量。方法的相对标准偏差为0.46%,加标回收率为98.17%～99.50%。适用于香兰素成品的分析,也可用于中间产品的控制分析。     

Liquid lithium surface control and its effect on plasma performance in the HT-7 tokamak

Experiments with liquid lithium limiters (LLLs) have been successfully performed in HT-7 since 2009 and the effects of different limiter surface structures on the ejection of Li droplets have been studied and compared. The experiments have demonstrated that strong interaction between the plasma and the liquid surface can cause intense Li efflux in the form of ejected Li droplets – which can, in turn, lead to plasma disruptions. The details of the LLL plasma-facing surface were observed to be extremely important in determining performance. Five different LLLs were evaluated in this work: two types of static free-surface limiters and three types of flowing liquid Li (FLLL) structures. It has been demonstrated that a FLLL with a slowly flowing thin liquid Li film on vertical flow plate which was pre-treated with evaporated Li was much less susceptible to Li droplet ejection than any of the other structures tested in this work. It was further observed that the plasmas run against this type of limiter were reproducibly well-behaved. These results provide technical references for the design of FLLLs in future tokamaks so as to avoid strong Li ejection and to decrease disruptive plasmas.     

Preliminary design and performance study of EAST liquid lithium limiter based on CPS

Lithium has the ability of H recycling suppression and impurities absorption and it can be used as plasma facing material (PFM) in tokamaks. Lithium conditioning experiments were launched on EAST, HT-7 and some other tokamaks for many years by using the methods of GDC, IRCF and evaporation. Liquid lithium has better performances in effective lifetime and heat removal aspects compared to non-liquid lithium. While, applying liquid lithium in the tokamak would cause the safety problem as the lithium can react with many substances violently and the magnetohydrodynamic behavior is difficult to be handled. EAST liquid lithium limiter (LLL) system is under developing and will be applied in EAST to study the main technologies of the liquid lithium application. The normal operation temperature of the limiter is expected as 230–550 °C under the active cooling of water. Capillary porous system (CPS) is used to prevent the lithium from splashing under large electromagnetic force by increasing the surface tension of the lithium. In order to investigate the cooling performance of the cooling design, the thermal-hydraulic analysis was done which shows that with 3 m/s flowing velocity, the water can keep the limiter under 550 °C all the time if the heat flux is lower than 0.7 MW/m². Under heat flux of 1 MW/m², the limiter should be retreated within 7 s to avoid erosion. The pressure drop of the coolant under 3 m/s is less than 40 kPa with temperature difference nearly 34 °C which meet the design requirements very well. The key manufacture process and technologies like vacuum bonding between the CuCrZr heat sink and 316L guide plate were well studied in the R&D process. The heating test on the test bench showed that the CPS can be heated efficiently by the heaters attached into the heat sink.     

A liquid metal cooling system for the thermal management of high power LEDs

An active cooling solution using liquid metal as the coolant was proposed for high power light emitting diodes (LEDs). The typical thermal-physical properties of liquid metal were presented. Then a series of experiments under different operation conditions were performed to evaluate the heat dissipation performance of the liquid metal cooling system, and the results were compared with that of water. In order to better understand the cooling capability of liquid metal cooling system, a theoretical thermal resistance model was established and discussed. Both the experiments and theoretical analysis indicated that liquid metal cooling was a powerful way for heat dissipation of high power LEDs, and the fabrication of practical liquid metal cooling devices was feasible and useful.     

SiNx烧穿工艺下硅太阳电池结构研究

介绍了在全国产设备构成的中试线上开展的高效单晶硅太阳电池研究工作,并制备出了最高转换效率达15.7%的单体电池(面积103×103mm2).实验采用PECVD方法制备SiNx减反、钝化薄膜,并采用正背面电极一次金属化烧结技术,同时完成氮化硅薄膜烧穿工艺.实验还研究了PECVD硅烷与氨气流量比对SiNx钝化、光学和保护性质的影响.分析了氮化硅薄膜及简化新工艺与提高太阳电池效率的关系.实验最后采用化学染色法测量了太阳电池的p-n结结深,结果表明该太阳电池的p-n结为0.25 μm的浅结,直接证明了SiNx薄膜对p-n结有良好的保护作用.     

An analytical solution for air dehumidification by liquid desiccant in a packed column

This paper presents a new analytical solution of heat and mass transfer processes in a packed bed liquid desiccant dehumidifier based on the equilibrium humidity on the interface is assumed to be constant. In order to maintain the partial pressure difference on the interface, a high liquid desiccant flow rate is often applied in the practical absorber. Therefore, for a narrow range of operating conditions for practical dehumidification process, we can assume that the equilibrium humidity ratio on the interface is constant. The assumption of constant humidity ratio is applied in this paper for derivation of the analytical solution. The model and the analytical solution predictions were compared against a reliable set of experimental data available in the literature, with very good agreement. According to the Lewis definition in this present study, the Lewis number obtains 0.9. The effects of variables such as air and liquid desiccant flow rate, air temperature and humidity, desiccant temperature and concentration have been investigated on the condensation rate. The results present that design variables such as desiccant concentration, desiccant temperature, air flow rate, and air humidity ratio have the greatest impact on the performance of the dehumidifier. The liquid flow rate and the air temperature have not a significant effect. Furthermore, the effects of air and liquid desiccant flow rate have been reported on the humidity effectiveness of the column.     

Multi absorber stand alone liquid desiccant air-conditioning systems for higher performance

Achieving comfortable environment with the use of renewable energy or waste heat without creating the hazardous effects over the earth atmosphere are major challenges in the field of air-conditioning. Liquid desiccant technology is a promising option. For the past few decades research is going on worldwide to commercialize such systems. Hybrid liquid desiccant systems (combination of vapor compression (V-C) and liquid desiccant system) have got more attention probably due to higher COPs and lower regeneration temperature for such systems.In the present communication the steady-state performance of stand alone liquid desiccant systems has been simulated and analyzed. Falling film designs of absorber and regenerator have been selected for the study due to their lower pressure drops. The simulation of these components has been carried out by solving the basic mass and energy balance equations. These are nonlinear coupled first order differential equations, which have been solved by using fourth order finite difference Runge-Kutta method. The overall system has been simulated using Warner’s technique. Two new stand alone liquid desiccant cycles utilizing the potential of desiccant fully through multiple absorbers have been proposed. The proposed new cycles improve the COP of stand alone systems significantly. A parametric study has also been carried out on these liquid desiccant cycles to identify the key design parameters affecting the performance of the system.     

An experimental study of a solar-regenerated liquid desiccant ventilation pre-conditioning system

A solar-regenerated liquid desiccant ventilation pre-conditioning system has been installed and experiments were carried out for a period of nine months covering rainy, cold, and hot seasons in a hot and humid climate (Thailand). A heat exchanger was used to cool the dehumidified air instead of typical evaporative cooling to maintain the dryness of the air. The use of solar energy at the regeneration process and cooling water from a cooling tower makes the system more passive. The evaporation rate at the regeneration process was always greater than the moisture removal rate at the dehumidification process indicating that the concentration of the desiccant in the system would not decrease and so the performance would not drop during continuous operation. The system could reduce the temperature of the delivered air by about 1.2 °C while the humidity ratio was reduced by 0.0042 kg_w/kg_da equivalent to 11.1% relative humidity reduction. The experimental results were also compared with models in literature.