Influence of osmolytes on the stability of thylakoid‐based dye‐sensitized solar cells

In recent years, there has been considerable interest in incorporating naturally occurring components of the photosynthetic apparatus into man‐made solar cells, because of the high quantum efficiency of photosynthetic reaction centers. One hurdle to overcome regarding the use of native membranes in these devices is their limited lifespans. In this study, we used stabilizers to increase the long‐term viability of biomolecules in vitro, thereby alleviating this challenge. In this regard, it is known that osmolytes, such as glycine betaine (GB) and sucrose, preserve photosynthetic activity in isolated photosystems. Upon investigation of the thermal protection properties of GB and sucrose in thylakoid‐based dye‐sensitized solar cells, we report that the addition of GB and sucrose to the thylakoid photosensitizer maintains nonzero photocurrent in the thylakoid‐based solar cell upon heating to 50°C. At 50°C, the GB‐containing cell displayed about a fourfold increase in photocurrent than the control cell, in which the photocurrent was decreased to nearly zero. The addition of 0.5M and 1M sucrose has respectively caused nearly 40% and 70% increases in photoinduced electron transfer activity over the control at 35°С. Similarly, though to a lesser extent, 1M GB caused an approximate 40% increase in electron transfer activity as well. Moving forward, this approach will be extended to alternative membrane protein isolation strategies, allowing for an accurate comparison with traditional detergent‐isolated complexes, with the ultimate goal of developing a cost‐effective and sustainable solar cell.     

一种甜菜碱双子表面活性剂的合成及其性能研究

以油酸酰胺丙基叔胺,3-氯-2-羟基丙磺酸钠和1,4-二溴丁烷为原料,通过两步反应合成出了一种甜菜碱双子表面活性剂,通过傅立叶变换红外光谱仪和核磁共振仪对合成产物进行了结构表征,用表面张力仪测定不同浓度下油酸酰胺羟丙基甜菜碱（B18）和甜菜碱双子表面活性剂（B18-4-18）的表面张力,得出表面张力曲线,并用实验室定制的携液量装置分别测定了两种表面活性剂在清水中,矿化水中和凝析油中的携液率。实验证明：合成的化合物与预期合成物质一致,在25℃时,B18临界胶束浓度cmc=3.5914?0-6mol/L,相应的表面张力"γ" _cmc=36.2155mN/m,B18-4-18的临界胶束浓度cmc=3.3986?0-6 mol/L,相应的表面张力"γ" _cmc=34.6464mN/m;B18和B18-4-18在清水中的携液率可以达到87%,92%,在15万矿化水中的最高携液率可以达到82%,84%。在10%凝析油中的最高携液率可以达到64%,67%。     

Amphoteric surfactants: processing, product composition and properties

Cocamidopropyl betaine (CAPB) has been the most important secondary surfactant for personal-cleansing products for a long time. Its excellent toxicological profile is an important reason for its increasing use in oral-care products. Recently it has gained interest for further applications such as household cleaners, dish-washing liquids, and industrial and technical products. Imidazoline-derived amphoterics such as sodium cocoampho-acetate (SCAA) or diacetate play a more minor role than CAPB. Owing to the low irritation potential of the pure surfactant and its good toxicological properties, ampho-acetates have mainly found applications in cosmetics. Their industrial applications have been relatively small. While CAPB has a well-defined chemical structure from a straightforward production process, most imidazoline-derived amphoterics exhibit a complex composition of compounds with different structures. This depends on the production parameters. Improved processing methods have recently led to the commercial availability of well-defined SCAA with low levels of by-products. Modern production processes and the composition of high-purity amphoterics are reviewed. Raw materials and by-products are described, together with their analytical methods. The cosmetic performance, cleansing and foaming power, rheological effects and mildness-enhancing properties of both CAPB and SCAA are compared. La cocamidopropyl-betaine (CAPB) est, depuis longtemps le tensio-actif secondaire le plus important pour les produits d'hygiene personnelle. L'excellent profil toxicologique de la CAPB est certainement une raison majeure de son usage croissant dans les produits de soin buccaux. La CAPB a suscite depuis peu un interet pour des applications supplementaires telles que les nettoyants menagers, les liquides vaisselle, les produits industriels et techniques. Les derives amphoteres de l'imidazoline tels que le cocoampho-acetate de sodium (SCAA) ou le diacetate occupent une place mineure comparee a la CAPB. En raison du faible potentiel irritant du tensio-actif pur et meme de bonne proprietes toxicologiques, les ampho-acetates trouvent principalement leurs applications dans les cosmetiqes. Leur role dans les applications industrielles est relativement limite. Alors que la CAPB a une structure chimique bien definie a partir d'un procede de production direct, la plupart des derives amphoteres d'imidazoline presentent une composition complexe de composes aux structures differentes. Ceci depend des parametres de production. Des procedes de production ameliores ont recemment conduit a une disponibilite commerciale de SCAA bien definis avec de faibles teneurs en produits secondaires. Les procedes modernes de production et la composition d'amphoteres de grande purete sont decrits. Les matieres premieres et les produits secondaires sont decrits ainsi que leurs methodes d'analyse. Le comportement cosmetique, le pouvoir nettoyant et moussant, les effets rheologiques et les proprietes adoucissantes sont compares, a la fois pour la CAPB et le SCAA.     

甜菜碱对高盐废水的生物除磷影响初探

在高盐废水的生物处理中,由于高盐度胁迫作用,生物除磷效能普遍偏低。针对SBR系统生物除磷过程,通过监测出水总磷、磷酸盐、亚硝态氮的浓度,探究了甜菜碱的投加时期和投加量对高盐废水生物除磷的影响。研究结果表明:投加适量的甜菜碱能有效应对环境和盐度突变对系统除磷带来的负效应,增强SBR系统的鲁棒性;甜菜碱关键作用于好氧阶段,在曝气开始时投加甜菜碱更有利于生物除磷;在盐度突变的情况下,增加甜菜碱的投加量正反馈于磷酸盐去除率,但持续性不高。     

月桂酰胺丙基甜菜碱的合成及其性能

以自制的N ,N 二甲基 N′ 月桂酰基 1 ,3 丙二胺和氯乙酸钠为原料合成月桂酰胺丙基甜菜碱 ,通过改变反应温度、反应时间和氯乙酸钠的酸度 ,探索反应的优化条件 ,并对合成产品的起泡性、稳泡性和增稠性进行研究。结果显示 ,当反应温度为 70℃、反应时间为 5h ,氯乙酸钠的酸度为pH =6 0时 ,产物的活性物质量分数最高 ,为 (30 0± 1 6) % ;产物的起泡、稳泡、增稠性能高 ,与香波中的其他组分的相容性好     

椰油两性羧酸钠的性能研究

概述了国内外椰油两性羧酸钠（俗称两性咪唑啉甜菜碱,简称MAB）的发展过程,分析了其结构特征.对其水溶性、发泡、增稠、调理以及温和等性能作了详细的介绍.将6501和MAB分别与十二醇醚硫酸钠（SLES-2）复配,比较了其增稠、增泡性能随活性物添加量的变化,并用椰油酰胺丙基甜菜碱（CAB）、羟磺基甜菜碱（SHD）、MAB与SLES-2复配,测定了它们的增稠、增泡性能随pH值的变化.结果表明：在相同的条件下,MAB的增稠性能明显优于6501,发泡性能与6501相当.在中性至酸性的pH范围内,MAB与CAB和SHD相比,具有更好的黏度表现,3种物质的增泡能力相当.比较了目前市场上MAB主要生产厂家的产品性能,并列举了配方实例.     

Environmentally acceptable drag-reducing surfactants for district heating and cooling

The aim of this work was to find drag-reducing surfactants for both district heating and cooling that are environmentally more acceptable than the organic salts of quaternary ammonium compounds that so far have dominated this application. Vortex inhibition of test solutions in glass beakers has been used to screen a large number of surfactant mixtures, various electrolytes, and temperatures. For the most interesting products, the pressure drop in a test loop was measured at various flow rates and temperatures.N-cetyl sarcosinate andN-stearyl betaine, the latter together with Na-dodecylbenzene sulfonate, give good drag reduction (DR) properties at 65–100 and 45–85°C, respectively. The sarcosinate is sensitive to pH changes, whereas the betaine-sulfonate complex is more robust. Ethoxylates of oleic acid monoethanolamide show good DR properties at 0–25°C. At an increased salt concentration, a mixture of this surfactant with an ethoxylated oleyl alcohol worked well. At a still higher salt concentration, e.g., sea water, a combination ofN-cetyl betaine and alkylbenzene sulfonate showed DR.