The Resistivity Response of an Anisotropically Conductive Polymer Composite with in-situ Conductive Microfibrils During Cooling

The resistivity response of anisotropically conductive polymer composite (ACPC) with carbon black (CB) particles selectively localizing at the surfaces of aligned polyethylene terephthalate (PET) microfibrils was investigated during cooling from 180°C in the parallel and perpendicular directions. The ACPC exhibited a cooling positive temperature coefficient (PTC) around the crystallization temperature of polyethylene (PE) matrix. With the increase of CB loading, the cooling PTC effect decreased gradually. When the ACPC experienced isothermal annealing, the aligned microfibrils disordered to form more conductive pathways. The increase of annealing time caused the gradual attenuation of the cooling PTC effect in both directions.     

EFFICIENT NEW SYNTHESES OF POLYCYCLIC AROMATIC HYDROCARBON ORTHO-QUINONES AND THEIR 2′-DEOXYRIBONUCLEOSIDE ADDUCTS

Three mechanisms have been proposed to explain the carcinogenic activities of polycyclic aromatic hydrocarbons (PAHs). On the basis of the nature of the active metabolites involved, they may be termed: the diol epoxide mechanism, the quinone mechanism, and the radical-cation mechanism. In connection with studies to evaluate the relative importance of these pathways, we required practical methods for the syntheses of the active PAH metabolites involved. We now report efficient new synthesis of the o-quinones of benzo[a]pyrene (BPQ), 7,12-dimethylbenz[a]anthracene (DMBAQ), and benz[a]anthracene (BAQ). These quinones are convenient synthetic precursors of the related o-catechols, trans-dihydrodiols, and diol epoxides, as well as the stable adducts of the o-quinones with 2-deoxyadenosine and 2′-deoxyguanosine.     

模拟体液中Na/Mg/F共掺杂羟基磷灰石的制备和表征

采用化学沉淀法,在模拟体液环境中制备了Na、Mg、F三元素共掺杂的羟基磷灰石( HA)粉体,利用XRD、FT-IR、SEM、EDS等技术对其物相结构、微观形貌、化学组成和热稳定性进行了分析和表征。结果表明：Na/Mg/F对HA进行掺杂引起HA晶格发生畸变。 F元素的掺杂量对HA的形貌具有一定的影响;随着F掺杂量的增加,球形的HA颗粒逐渐转变成棒状结构。 F/P=0.25时,可以制得小而均匀的HA颗粒。抑菌环实验表明Na/Mg/F共掺杂HA对金黄色葡萄球菌的生长具有一定的抑制作用。 F/P=0.25时,抗菌性最强。煅烧温度在1000℃时HA的物相未发生变化,说明样品具有良好的热稳定性。     

“原子结构”入门知识的教学设计

无机化学中原子结构作为物质结构的入门知识抽象、公式复杂,学生很难适应,难以转变思维模式,严重影响整个物质结构知识、元素化学和后续课程的学习,若从预备知识结合化学史、三种描述方式、多媒体演示几方面进行教学设计,不仅激发学生学习兴趣和自信心,且能事半功倍。     

储氢材料领域全球专利申请态势分析

对储氢材料技术领域专利技的全球申请态势进行了全面深入的分析,包括专利申请趋势、主要申请人、技术产出国、目标国等的分析,得知全球储氢材料整体而言,申请趋缓;主要申请人以日本为主,技术主要集中在日本,专利分布主要集中在日、美、欧、中等经济体,为有关机构和个人提供了一个宏观的研究概况,有利于全面了解储氢材料行业的整体趋势提供专利学意义上的参考。     

聚醚砜的磺化与热性能

以浓硫酸为溶剂 ,氯磺酸为磺化剂对聚醚砜 (PES)进行了磺化 ,制备了不同磺化度的磺化聚醚砜 (SPES)。探讨了反应的影响因素 ,分析了 SPES的热稳定性。结果表明 SPES的 Tg较 PES升高 ,随着磺化度的增加 ,SPES的降解温度降低。     

三氟甲烷下游产品的研究开发

三氟甲烷在一定条件下会较容易地脱去H,形成活泼的二氟卡宾,可以方便地在医药、农药及特殊化学品中间体内引入三氟甲基和二氟甲基,得到有着特殊功效的含氟化合物。开发三氟甲烷可以节约生产成本,消除环境危害,更可以作为一种新型氟化试剂,在化工、医药、农药展开多种新颖应用。     

Gas drying with ionic liquids

The gas drying technology with ionic liquids (ILs) was systematically studied ranging from the molecular level to industrial scale. The COSMO‐RS model was first used to screen the suitable IL and provide theoretical insights at the molecular level. Toward CO₂ gas dehydration, we measured the CO₂ solubility in single [EMIM][Tf₂N] and in the [EMIM][Tf₂N] + H₂O mixture, as well as the vapor‐liquid equilibrium (VLE) of [EMIM][Tf₂N] + H₂O system, to justify the applicability of UNIFAC model. Based on the thermodynamic study, the rigorous equilibrium (EQ) stage mathematical model was established for process simulation. The gas drying experiment with IL was also performed and the water content in gas product can be reduced to 375 ppm. It was confirmed that a less flow rate of absorbent, a higher CO₂ recovery ratio and a much lower energy consumption can be achieved with IL than with the conventional triethylene glycol (TEG). © 2017 American Institute of Chemical Engineers AIChE J, 64: 606–619, 2018     

Synthesis of an Alkyl Polyoxyethylene Ether Sulfonate Surfactant and Its Application in Surfactant Flooding

Surfactant flooding as a potential enhanced oil‐recovery technology in a high‐temperature and high‐salinity oil reservoir after water flooding has attracted extensive attention. In this study, the synthesis of an alkyl alcohol polyoxyethylene ether sulfonate surfactant (C₁₂EO₇S) with dodecyl alcohol polyoxyethylene ether and sodium 2‐chloroethanesulfonate monohydrate, and its adaptability in surfactant flooding were investigated. The fundamental parameters of C₁₂EO₇S were obtained via surface tension measurement. And the ability to reduce oil–water interfacial tension (IFT), wettability alteration, emulsification, and adsorption was determined. The results illustrated that IFT could be reduced to 10^?3 mN m^?1 at high temperature and high salinity without additional additives, and C₁₂EO₇S exhibited benign wettability alternate ability, and emulsifying ability. Furthermore, the oil‐displacement experiments showed that C₁₂EO₇S solution could remarkably enhance oil recovery by 16.19% without adding any additives.