Dual-Zone Photothermal Evaporator for Antisalt Accumulation and Highly Efficient Solar Steam Generation

Interfacial solar steam generation offers a promising and cost-effective way for saline water desalination. However, salt accumulation and deposition on photothermal materials during saline and brine evaporation is detrimental to the stability and sustainability of solar evaporation. Although several antisalt strategies are developed, it is difficult to simultaneously achieve high evaporation rates ( > 2.0 kg m⁻² h⁻¹) and energy efficiencies. In this study, a self-rotating photothermal evaporator with dual evaporation zones (i.e., high-temperature and low-temperature evaporation zones) is developed. This photothermal evaporator is sensitive to weight imbalance ( < 15 mg) thus is able to quickly respond to salt accumulation by rotation to refresh the evaporation surface, while the dual evaporation zones optimize the energy nexus during solar evaporation, simultaneously realizing excellent salt-resistant performance and high evaporation rate (2.6 kg m⁻² h⁻¹), which can significantly contribute to the real-world application of solar steam generation technology.     

ZnO四足和多足纳米结构的制备和光致发光性能研究

采用简单的热蒸发法,在没有使用载气和催化剂的情况下成功制备出ZnO四足和多足纳米结构。采用场发射扫描电镜、X射线衍射、高分辨透射电子显微镜和荧光分光光度计研究了ZnO纳米结构的形貌、结构和光致发光性能。结果表明所合成的ZnO是由具有六方纤锌矿结构的四足和多足纳米结构组成,足部呈棒状并沿[0001]方向生长。提出了四足和多足ZnO纳米结构的生长机制。在室温下的光致发光光谱中,494nm处出现一个较强的绿色发射峰,391nm处出现一个较弱的紫外发射峰。     

空间太阳电池玻璃盖板表面超薄ITO防静电层的设计及制备工艺

ITO/MgF2复合薄膜既具有较好的表面导电性能又具有较高的透过率,可应用于空间太阳电池玻璃盖板表面。文章主要对ITO/MgF2复合薄膜中表层的超薄ITO薄膜进行了研究。利用TFCalc软件模拟了ITO薄膜厚度对ITO/MgF2复合薄膜光学性能的影响,根据模拟结果采用电子束蒸发法在衬底上依次沉积MgF2薄膜和氧化铟锡(ITO)薄膜,研究了ITO薄膜工艺参数(沉积速率、沉积温度和工作气压)和ITO薄膜厚度对ITO/MgF2复合薄膜光电性能及微观结构的影响。当ITO薄膜沉积速率为0.05nm/s、沉积温度为400℃、工作气压为2.3×10~(-2) Pa、厚度为10nm时,表层ITO薄膜基本连续,其方块电阻(1.94kΩ/)已符合设计需求,ITO/MgF2复合薄膜在可见光区间(400~800nm)的平均透过率达到89.00%。     

A shear pan mill for preparation of ultrafine polyamide 66 powder using sodium sulfate ionic crystals as grinding aid

Fine polyamide 66 (PA66) powder was prepared in a shear pan mill that was designed and developed in our laboratories. In contrast with discontinuous impacts in the ball mill, the size reduction operation in the pan mill is characterized by application of uninterrupted strong shear forces on particles. It has been found that as compared to the ball mill, much finer pulverization of the polymer material is achieved in the pan mill, in spite of the high strength and ductility of the polymer. Sodium sulfate ionic crystals with hard and pointed edge were co-milled with PA66 to further cut the fine polymer particles into ultrafine powder (2–5?µm). Besides acting as a grinding aid, the ionic crystals also prevented conglutination and aggregation of the polymer powder. Furthermore, PA66 powder could be conveniently separated and purified from the co-milled grinding aid-polymer mixture by simple water washing and filtration. Thus, an energy efficient and environment-friendly technology has been developed to prepare the ultrafine plastic powder at room temperature. This process holds a good promise for commercial applications.     

热泵驱动废液浓缩装置性能研究

本文针对工业废水排放,设计并研发了一套废水浓缩处理装置,以低温蒸发技术为依据,以热泵作为装置的主要驱动能源,空气作为循环介质,对含水率为95%的铜管清洗液进行浓缩处理。对装置的主要原理部件进行了介绍,建立了填料室的传质传热模型,通过Matlab编程确定填料尺寸为300 mm×400 mm×500 mm,搭建了实验台进行实验测试与能效分析。结果表明：装置能够稳定运行,凝结水量达到15 L/h,此时热泵功率为5.46 kW,装置能效比达到4.54,装置内循环空气温度变化为31 ℃到43 ℃,相对湿度达到94.6%,装置持续运行一段时间后达到最大浓缩程度,体积为原溶液的3/4左右,且出水程度较好,减少了工业废水处理的成本。     

低温推进剂地面加注停放阶段蒸发量分析

建立了一种可以描述低温推进剂加注、停放过程的计算模型,分析了影响低温推进剂加注停放阶段蒸发的主要因素。研究表明:为缩短发射组织时间、优化加注流程、提升推进剂品质,在全系统能力范畴内,低温推进剂加注过程应提高推进剂加注速度,降低推进剂加注温度,尽量减小外界环境漏热率,并适当增加系统排气能力。     

双乳液体系在微胶囊制备中的应用研究进展

双乳液是一类多重乳状液体系,它具有保护物质并且可以控制这些物质从一个相释放到另一个相的能力。近年来这类乳液体系与传统微胶囊制备方法的结合在药物输送(如抗癌药物、激素等)、食品等领域得到了一定的应用,解决了传统微胶囊制备方法无法有效封装高度水溶性物质等问题。基于此,综述了双乳液体系与微胶囊制备方法结合延伸出的一些新方法,包括双乳液-复凝聚法、复乳溶剂挥发法以及膜乳化复乳法等;同时,评述了影响双乳液体系制备微胶囊的各种因素,展望了双乳液体系在农药微胶囊制备中的应用前景。     

The self-aligning behaviour of graphene nanosheets in the styrene butadiene rubber by controlling curing temperature

This paper presents a simple strategy that utilizes the regulation of curing temperature to control the orientation of the aligned graphene nanosheets (GNSs) in styrene butadiene rubber (SBR). GNSs would settle from the well-dispersed GNSs suspensions with the styrene butadiene latex (SBL) mixture under the field of gravity to form parallel-aligned GNSs composites with enough standing time at a lower curing temperature. The vertical-aligned GNSs composites were formed by the combined effect of gravity and steam inductive force within a higher curing temperature. The detail forming mechanisms were discussed in the investigation. The parallel-aligned GNSs/SBR composites demonstrated anisotropic conductivity between the parallel and the perpendicular directions. Along with parallel direction, a percolation threshold value of the GNSs was 0.13 wt%, and 0.58 S/cm and of electric conductivity was attained when the GNSs content was 3 wt%. Along with vertical direction, it the GNSs showed insulating property.     

西藏那曲流域典型测站气候特征分析

以西藏那曲流域的安多站和那曲站两个气象站点逐日气象数据为基础,分别采用Mann-Kendall检验、最大熵谱分析、滑动t检验、Yamamoto检验等方法对两站点的降水量、无雨日、年平均气温以及潜在蒸散量的趋势性、周期性、突变性进行检验,并对降水的年内分配以及不同强度的降水变化趋势进行分析。结果表明:安多站和那曲站年降水量呈显著上升趋势,无雨日显著下降;降水以夏季降水为主,主要分布在6~9月,且以小雨等级为主,中雨次之;各等级降水的年降水量和频次均呈上升趋势;年平均气温、年最低最高气温均呈上升趋势,且年最低气温上升趋势较年最高气温显著,两站年最大温差呈下降趋势;潜在蒸散量的变化趋势与年平均气温的趋势相似。