Mechanism of droplet generation in silver thin films for organic light-emitting diode displays

Thin silver film is widely used as the cathode in organic light-emitting diode displays and it is generally fabricated using the thermal evaporation method. But during the evaporation process, there is an inevitable outgassing problem and this creates high viscosity bubbles in melted silver. When the bubbles break, the high energy released scatters silver droplets which damage the silver surface. In this study, we were able to decrease the number of droplets from 6,171 to 278 with a degassing process of 400 °C for 6 h before proceeding with a thermal evaporation process.     

硫化铅锌锑矿一步获取金属新工艺的研究

根据名锌锑钨具有易挥发的特征，研究了金属硫化矿物在有ＣａＯ存在的条件下，用水煤气或氢气低浊直接还原，同时固硫，继而高温挥发一步获得金属或合金。     

Production of Microencapsulated Crawfish (Procambarus clarkii) Astaxanthin in Oil by Spray Drying Technology

In this study, an emulsion prepared with flaxseed oil containing crawfish astaxanthin, sodium caseinate, lactose, and water was spray dried to produce microencapsulated flaxseed oil containing crawfish astaxanthin powder (MCA). Production rate and energy used to produce MCA were estimated. Physicochemical properties and storage stability of MCA were determined. The energy required to spray dry the microencapsulated flaxseed oil containing astaxanthin was 2.36 × 10⁴ kJ/kg of emulsion. The microencapsulation efficiency for MCA was 86.06%, which indicated that more oil was encapsulated than on the particles’ surfaces. The particle size of MCA ranged from 6 to 100 µm. The astaxanthin concentration in MCA was 13.76 μg/g powder and alpha-linolenic acid (ALA) was the predominant fatty acid (53%) in MCA. Degradation of astaxanthin in MCA followed first-order reaction kinetics and could be well described by the Arrhenius equation. The astaxanthin in MCA was more stable when the powder was stored at 5°C than at 25 or 40°C.     

船用直喷式柴油机燃油蒸发、燃烧模型

为了更好地预测船用柴油机的性能，改进了包括燃油蒸发和燃烧过程的准维多区燃烧模型，该模型采用数值模拟计算方法，考虑了缸内工质的对流辐射换热，用正十六烷和α－甲基萘按适当比例混合来模拟燃油，在空气卷吸计算中考虑了燃油碰壁和着火对空气卷吸的影响，经实验验证，本模型理论计算与实测结果吻合良好，表明本模型对柴油机工作过程的模拟是正确的，应用本模型可以方便地预测发动机的性能。     

蒸发冷却降温技术在变压器中的应用

对以F－113为制冷剂的一台蒸发冷却变压器样机进行了试验。通过与相对应的油浸变压器数据进行比较，表明蒸发冷却降温技术在变压器中应用是可行的。     

Simulation and Empirical Studies of Solvent Evaporation Rates in Vacuum Evaporation Crystallization

Simulation results for continuous vacuum evaporation crystallization obtained by Aspen Plus and experimental results for semi‐batch vacuum evaporation crystallization are presented. In the crystallization experiments, the fixed heat duty was used to compare the water evaporation rates and crystal properties obtained at different pressures. The solution selected was aqueous glycine. It has the ability to form a number of different crystalline polymorphs, which allows it to exhibit a variety of different physical properties while maintaining its chemical properties. X‐ray diffraction results demonstrated that mainly the γ‐crystal form is produced under the conditions applied in vacuum evaporation crystallization.     

An improved algorithm for disaggregating microwave-derived soil moisture based on red, near-infrared and thermal-infrared data

Accurate high-resolution soil moisture data are needed for a range of agricultural and hydrologic activities. To improve the spatial resolution of ∼ 40 km resolution passive microwave-derived soil moisture, a methodology based on 1 km resolution MODIS (MODerate resolution Imaging Spectroradiometer) red, near-infrared and thermal-infrared data has been implemented at 4 km resolution. The three components of that method are (i) fractional vegetation cover, (ii) soil evaporative efficiency (defined as the ratio of actual to potential evaporation) and (iii) a downscaling relationship. In this paper, 36 different disaggregation algorithms are built from 3 fractional vegetation cover formulations, 3 soil evaporative efficiency models, and 4 downscaling relationships. All algorithms differ with regard to the representation of the nonlinear relationship between microwave-derived soil moisture and optical-derived soil evaporative efficiency. Airborne L-band data collected over an Australian agricultural area are used to both generate ∼ 40 km resolution microwave pixels and verify disaggregation results at 4 km resolution. Among the 36 disaggregation algorithms, one is identified as being more robust (insensitive to soil, vegetation and atmospheric variables) than the others with a mean slope between MODIS-disaggregated and L-band derived soil moisture of 0.94. The robustness of that algorithm is notably assessed by comparing the disaggregation results obtained using composited (averaged) Terra and Aqua MODIS data, and using data from Terra and Aqua separately. The error on disaggregated soil moisture is systematically reduced by compositing daily Terra and Aqua data with an error of 0.012 vol./vol.     

Molecular simulations of droplet evaporation by heat transfer

Droplet evaporation by heat transfer is investigated by molecular dynamics simulations for a pure Lennard-Jones fluid. Two different initial conditions are treated: (1) a droplet surrounded by its vapor in equilibrium, (2) a cold droplet surrounded by warm vapor. In both cases heat is transferred from a heat bath. Results are the numbers of droplet molecules N _d and density, drift velocity, and temperature profiles as functions of time. For the small droplets considered N _d depends on the definition of a droplet molecule. The density profiles as function of time show a transition from a droplet with liquid–vapor interface to a cluster of interfacial type and finally to the gas state. The temperature at a given time is nearly constant within the droplets or clusters but strong gradients occur in the gas. In case of evaporation of a cold droplet surrounded by warm vapor we observed initially cooling down of the droplet corresponding to pressure jump evaporation and thereafter slower evaporation because of lower initial state vapor density.     

Simple Equation to Estimate Reference Evapotranspiration from Evaporation Pans Surrounded by Fallow Soil

Reliable estimates of reference evapotranspiration (ET0) are key elements for efficient water resource management, and estimating ET0, based on “Class ‘A’ pan evaporation” data is common in arid climates. A pan coefficient (Kp), which depends on the distance (or fetch) of green vegetation or fallow soil around the pan (F), wind run (U), and relative humidity (RH), is used to convert from pan evaporation to ET0. Several researchers have developed models for estimating Kp values for pans surrounded by green vegetated fetch, but there is only one equation to estimate Kp values for dry fetch conditions. The equation is complex, so the objective of this research was to develop a new simple equation to estimate Kp under fallow soil fetch conditions. The new Kp equation and the more complex equation were compared with tabular values published by the United Nations Food and Agriculture Organization. The new equation performed slightly better at matching the tabular Kp values than the complex equation. The equation derivation and evaluation are presented.     

Maximization of Water Storage in Backfilled and Lined Channels and Dimples Subject to Evaporation and Leakage

A channel or axisymmetric dimple filled with a coarse porous material and aimed at a temporary storage of infiltrated water as a perched water table aquifer is studied. The bottom shape is varied based on the criterion of maximal water storage after a certain period of drainage and evaporation. Leakage into the vadose zone through a thin liner occurs with a specific discharge proportional to the pressure drop across the liner. Evaporation through a horizontal shrinking water table is spatially uniform. An ordinary differential equation, which follows from the mass balance condition, is solved either explicitly or numerically. The class of triangular, polynomial, and conical sections is studied. The shape of maximal water retention is calculated for a given initial stored water volume or water table width, evaporation intensity, liner thickness and conductivity, vadose zone pressure beneath the liner, and selected time interval between two sequential infiltration events.