Efficiency enhancement by mixed cation effect in dye-sensitized solar cells with a PVdF based gel polymer electrolyte

This paper reports the effect of using a mixed iodide salt system with two dissimilar cations to enhance the efficiency of dye-sensitized solar cells made with polyvinylidenefluoride (PVdF) based gel electrolyte. Instead of a single iodide salt, a mixture of potassium iodide (KI) with a small K⁺ cation and tetrapropylammonium iodide (Pr₄NI) with a bulky Pr₄N⁺ cation were used to provide the required iodide ion conductivity. Solar cells of configuration FTO/TiO₂/Dye/electrolyte/Pt/FTO were fabricated using a mesoporous TiO₂ electrode sensitized with a Ruthenium dye (N719). With identical electrolyte compositions, the cells with KI and Pr₄NI alone gave efficiencies of 2.37% and 2.90% respectively. The cell with the mixed iodide system, KI:Pr₄NI = 16.6:83.4 (% weight ratio), however, showed an enhanced efficiency of 3.92% with a short circuit current density of 9.16 mA cm⁻², open circuit voltage of 674.4 mV and a fill factor of 63.4%.     

浇筑式钢桥面铺装层推挤变形病害机理分析

以贵州省北盘江大桥钢桥面铺装层推挤变形病害为研究背景,采用凝胶渗透色谱法(GPC)和傅里叶变换红外光谱法(FTIR),从沥青分子尺度分析钢桥面铺装产生推挤变形的原因。分析结果表明:沥青老化并不是造成钢桥面铺装层推挤变形的主要原因;从现场调查可知,第2层粘层粘结能力的降低是造成钢桥面铺装层推挤变形病害的次要原因;通过级配分析发现,造成钢桥面铺装层推挤变形的主要原因是浇筑式沥青混合料(GA)级配偏细以及GA中集料颗粒的棱角性较差所致。     

Investigation of injectable drospirenone organogels with regard to their rheology and comparison to non-stabilized oil-based drospirenone suspensions

The objective of this study was to evaluate organogels as potential injectable drug-delivery systems for drospirenone (DRSP). Recently, studies on organogel characterization with focus on the parenteral injection are rarely to find in the literature. DRSP organogels contained the drug suspended in medium-chain triglycerides and were stabilized by various organogelators. The DRSP organogels were assessed in comparison to non-stabilized DRSP microcrystal suspensions (MCSs). Furthermore, rheological properties of the organogels, in particular the elastic modulus (G′), the complex viscosity (η*) and the elasticity, were evaluated with respect to the long-term stability, syringeability/injectability and in vitro release. DRSP organogels showed significantly improved storage stability compared to non-stabilized MCSs with regard to sedimentation and particle growth. Furthermore, all of the DRSP organogels showed shear-thinning behavior. Thus, ejection from syringes was possible by an autoinjector using 23G needles comparable to non-stabilized MCSs. Nevertheless, DRSP organogels exhibited significantly more sustained drug release than non-stabilized MCSs most likely caused by partial recovery of the organogelator structures at 37?°C after destruction. Consequently, DRSP organogels were evaluated to be superior to conventional non-stabilized MCSs. Silica organogels, which provided the highest elasticity, moderate G' and η* and avoided most efficiently particle growth, are slightly more preferable compared to the other DRSP organogels.     

四川盆地东南地区龙马溪组页岩气有效保存区综合评价

受差异构造边界的制约,四川盆地东南地区(简称川东南)中新生代发生差异构造变形,使得保存条件成为控制该区下古生界页岩气富集的主要因素。为此,从制约保存条件的直接原因——构造作用出发,对该区页岩气保存条件进行了综合评价。首先以构造研究为先导,立足于中新生代差异构造变形方式和强度,将评价区划分为7个构造形变带,并对各构造形变带的断裂规模、断裂密度、顶底板岩性和厚度、目的层埋深、构造形态和裂缝间距指数等影响因素进行系统揭示,确立页岩气有效保存区的评价指标和标准,建立页岩气保存条件综合评价体系。在此基础上,依据该区页岩气保存条件最优评价参数标准,对7个构造形变带下志留统龙马溪组页岩气的保存条件进行了宏观评价。结果表明:齐岳山断裂以西地区的保存条件整体上好于东侧;齐岳山断裂以东地区,以武隆断褶带的保存条件为最好,其次为彭水断褶带和黔江断褶带,道真叠加断褶带、务川叠加断褶带和沿河叠加断褶带相对较差。     

Two-step purification strategy for enhanced recovery of recombinant hepatitis B surface antigen from Pichia pastoris

Univariate screening on factors affecting the purification performance of recombinant hepatitis B surface antigen (HBsAg) on ion exchange chromatography (IEC) and size exclusion chromatography (SEC) and the establishment of a two-step purification strategy were performed. Amongst four IEC adsorbents examined, the use of Q Sepharose XL IEC adsorbent under optimized conditions together with optimized SEC purification was able to efficiently purify HBsAg. An established purification strategy comprising the two techniques further demonstrated adaptability for scale-up operations with a final total purification factor (PF) of 94.82 ± 16.20, HBsAg purity of 95.48% and recovery yield of 78.07%.     

水驱后凝胶与表活剂交替注入驱油效果

针对裂缝性低渗透油藏注入水易沿裂缝突进、含水上升快、水驱效果不理想的情况,开展了水驱后凝胶与表活剂交替注入方式提高采收率室内实验研究。通过室内凝胶体系成胶特性和稳定性评价,筛选出与实际油藏区块注入水配伍的凝胶体系。选择甜菜碱两性表面活性剂用于活性剂驱,开展了双管并联岩心体系驱油效果研究。研究结果表明:凝胶与表活剂交替注入可明显提高注入压力,该体系的采收率平均值为12.03%,低渗岩心的采收率略高于高渗透岩心采收率。与表活剂驱、聚合物与表活剂交替注入相比,驱油效果更好,可以作为裂缝性低渗透油藏水驱后进一步提高采收率的技术。     

基于可调偏振度源验证偏振光谱强度调制系统

研制了一种结构简单、稳定性好的可见光波段可调偏振度光源,用来验证偏振光谱强度调制(PSIM)实验系统设计的正确性。该光源内部安装有两块K9玻璃组成的玻璃片堆,通过改变玻璃片堆的倾角来调整输出的部分偏振光的偏振度。理论推导了二者的关系,得到了可调偏振度源输出光的偏振度计算方法。根据PSIM系统的实现原理,搭建了验证PSIM性能的实验装置,对可调偏振度源输出的不同偏振度谱进行了测量。实验结果表明:在PSIM实验装置的有效工作波段范围内,可调偏振度源输出光的理论偏振度值与PSIM实验装置测得结果的误差在1%以内,验证了可调偏振度源及PSIM实验装置设计的正确性。该装置有望成为标准偏振光源,用于偏振光谱测量装置的精确标定。     

钛交联蒙脱石制备条件的研究

以鄂东钙基蒙脱石提纯、钠化后（d001=1．28nm）为基质原料，用钛酸正丁酯[Ti（n-C4H9O）4]为钛源，采用溶胶-凝胶法制备了一系列钛交联蒙脱石纳米复合材料（Ti—PILCs）；并对水／丙酮比、Ti/土比、交联反应时间、不同溶剂等制备条件进行了分析，试验条件下，可获得d001值达3．74nm的大孔结构Ti—PILCs高纯蒙脱石复合材料。     

紫外固化涂料固化工艺参数的研究

本文研究了UV固化工艺参数与涂层性能的关系,实验显示涂层厚度影响着涂层的硬度、附着力、柔韧性和耐磨擦性能,UV固化光源和制造环境对涂层材料性能同样有较大的影响.设计合理的涂层厚度,选择合适的固化工艺和环境条件,可以获得目标性能的涂层.     

界面层对高强度聚焦超声所致焦斑的影响

用纳米铁磁性颗粒胶合体制作界面层,用同一剂量高强度聚焦超声(HIFU)在该界面层下方不同深度定点辐照.结果显示:焦点上缘与声学界面重合时,HIFU所致焦斑/损伤点(lesion)的体积增大,说明声学界面能够提高治疗效率；当焦点距离界面层10mm时,焦点处HIFU所致焦斑/损伤点的大小和形态与对照组相似,而界面处出现另一...