EFFECTS OF SOLVENT TREATMENT ON SURFACE MORPHOLOGY AND COMPOSITION OF POLY(METHYL METHACRYLATE)-g-POLY(ETHYLENE OXIDE)

Surface morphology and composition of solution-cast films of poly(methyl methacrylate)-g-poly(ethylene oxide)(PMMA-g-PEO) were investigated by using XPS, DSC, SEM and contact angle measurement. The microphase separatedstructure of the copolymers was studied by TEM. Generally, for the same graft copolymer, the surface content of PEO orhydrophilicity can be as follows: Surface treated with petroleum ether or cyclohexane>surface untreated with solvent>surface treated with water or ethyl alcohol. Graft copolymer having longer PEO side chains and higher PEO content shows aseparated PEO phase with even a certain degree of crystallinity on the surface. PEO crystallinity was destroyed by water orethyl alcohol treatment, however, surface treatment with petroleum ether or cyclohexane favors the growth of PEO crystal.TEM shows that graft copolymers with longer PEO side chains (M_n of PEO, 3200) may readily undergo microphase separation and the shape and size of domains depend on the copolymer's composition.

Stable and high performance all-inorganic perovskite light-emitting diodes with anti-solvent treatment

Optoelectronic applications based on the perovskites always face challenges due to the inherent chemical composition volatility of perovskite precursors. The efficiency of perovskite-based light-emitting diodes(Pe-LEDs) can be enhanced by improving the perovskite film via solvent engineering. A dual solvent post-treatment strategy was applied to the perovskite film, which provides a synchronous effect of passivating surface imperfections and reduces exciton quenching, as evidenced by improved surface morphology and photoluminance. Thus, the optimized Pe-LEDs reach 17,866 cd · m-2 maximum brightness, 45.8 cd · A-1 current efficiency, 8.3% external quantum efficiency, and relatively low turn-on voltage of2.0 V. Herein, we present a simple technique for the fabrication of stable and efficient Pe-LEDs.

Effect of slow-solvent-vapour treatment on performance of polymer photovoltaic devices

In this work, enhanced poly（3-hexylthiophene）：[6,6]-phenyl-C61-butyric acid methyl ester （P3HT：PCBM） bulk- heterojunction photovoltaic devices are achieved via slow-solvent-vapour treatment. The correlations between the morphology of the active layer and the photovoltaic performance of polymer-based solar cell are investigated. The active layers are characterized by atomic force microscopy and optical absorption. The results show that slow-solvent- vapour treatment can induce P3HT self-organization into an ordered structure, leading to the enhanced absorption and efficient charge transport.

Solvent-vapour treatment induced performance enhancement of amplified spontaneous emission based on poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene]

In this work, performance enhancements of amplified spontaneous emission （ASE） from poly[2-methoxy-5-（2＇- ethyl-hexyloxy）-l,4-phenylene vinylene] （MEH-PPV） have been achieved via solvent vapour treatment. Correlations between the morphology of the film and the optical performance of polymer-based ASE are investigated. The active layers are characterised by atomic force microscopy and optical absorption. The results show that the solvent-vapour treatment can induce the MEH-PPV self-organisation into an ordered structure with a smooth surface, leading to enhanced optical gain. Thus the solvent-vapour treatment is a good method for improving the optical properties of the MEH-PPV.

Carbon spheres prepared via solvent-thermal reaction method and their microstructures after high temperature treatment

Carbon spheres with size of 50-300 nm were synthesized via a solvent-thermal reaction with calcium carbide and chloroform as reactants in a sealed autoclave.The morphologies and microstructures of carbon spheres before and after high temperature treatment(HTT) were characterized by X-ray diffractometry(XRD) ,scanning electronic microscopy(SEM) ,energy diffraction spectroscopy(EDS) ,and transmission electron microscopy(TEM) .The formation mechanism of carbon spheres was discussed.The results indicate that the carbon spheres convert to hollow polyhedron through HTT.Carbon spheres are composed of entangled and curve graphitic layers with short range order similar to cotton structure,and carbon polyhedron with dimension of 50-250 nm and shell thickness of 15-30 nm.The change of solid spheres to hollow polyhedron with branches gives a new evidence for formation mechanism of hollow carbon spheres.

改性氧化石墨烯膜处理印染废水的能力与机理

在m[硫脲(TU)]∶m[氧化石墨烯(GO)]=1∶2、pH=9、反应温度80℃、反应时间60 min的条件下制备了TU改性GO纳米片(记为TU-GO),将TU-GO在聚醚砜(PES)微孔膜上沉积,制备出TU改性GO膜(记为TU-GOM)。当TU-GOM在PES上的负载量为238.73 mg/m^(2)时,其对甲基橙(MO)、罗丹明B(Rh B)、亚甲基蓝(MB)的截留率分别为94.01%、87.07%和99.67%。为优化TU-GO对Rh B的截留效果,使用TU和氯化胆碱(Ch Cl)组成低共熔溶剂(DES)制备了改性氧化石墨烯膜(DES-GOM)。在m(TU)∶m(Ch Cl)=1∶2、改性温度90℃、改性时间1 h的最佳条件下,制备的DES-GOM对MO、MB的截留率分别为93.95%、99.24%,对Rh B截留率提升至99.16%。采用SEM、EDS、FTIR、XRD及拉曼光谱对样品进行了表征,对TU交联GO过程的还原机理和增稳机理进行了分析。

C.I.颜料黄155的溶剂法颜料化工艺研究

为提高C.I.颜料黄155的应用性能,由2-氨基-对苯二甲酸二甲酯经重氮化反应后再与1,4-双乙酰乙酰对苯二胺偶合,得到C.I.颜料黄155粗品,分别采用有机溶剂N,N-二甲基甲酰胺(DMF)、N-甲基吡咯烷酮(NMP)对其进行处理以及水热处理,得到各C.I.颜料黄155样品。并讨论了溶剂处理对C.I.颜料黄155颜料的颜色、晶型、热稳定性、水接触角、粒径等性能的影响。结果表明:C.I.颜料黄155粗品经过DMF和NMP颜料化后,颜料结晶度较高且粒径减小,颗粒分布变窄,溶剂处理后的C.I.颜料黄155着色力可达109.9%,疏水性增大。

冷轧油泥的无害化处理与资源化利用

冷轧油泥是钢铁厂冷轧工艺产生的危险废弃物。作为油水固三相高度乳化的混合物,冷轧油泥组成十分复杂,若通过传统的焚烧或填埋法处理会造成严重的环境污染。目前处理冷轧油泥的工艺包括热解法、溶剂萃取法、热化学清洗法等,以将油固两相分离并分别回收。冷轧油泥废水是高浓度的有机废水,通常采用“预处理+深度降解”的复合工艺加以处理。通过油固两相的资源化,以及水相的减量化、无害化,可以实现危废品冷轧油泥的资源回收,变废为宝。

Effects of acetone-soaking treatment on the performance of polymer solar cells based on P3HT/PCBM bulk heterojunction

The improvement of the acetone-soaking treatment to the performance of polymer solar cells based on the P3HT/PCBM bulk heterojunction is reported. Undergoing acetone-soaking, the PCBM does not distribute uniformly in the vertical direction, a PCBM enrichment layer forms on the top of the active layer, which is beneficial to the collec- tion of the carriers and blocking the inverting diffusion carriers. X-ray photoelectron spectroscopy （XPS） analysis reveals that the PCBM weight ratio on the top of the active layer increases by 20% after the acetone-soaking treatment. Due to the nonuniform distribution of PCBM, the short-circuit current density, the open-circuit voltage, and the fill factor are enhanced significantly. Finally, the power conversion efficiency of the acetone-soaking device increases by 31% compared with the control device.

我院内科中药注射剂使用情况分析

目的分析我院内科住院患者中药注射剂使用情况,为中药注射剂的合理使用提供参考。方法抽取2020年11月1日至30日我院内科住院患者病历,共285份,对使用中药注射剂患者的年龄、性别、用药种类、用法用量、疗程、联合用药等情况进行统计和分析。结果患者平均年龄(63.50±10.68)岁;共涉及15种中药注射剂;中药注射剂用法用量符合率为97.71%;溶媒选择的符合率是95.47%;中药注射剂的使用疗程多集中在7~9 d,占58.59%。结论我院内科中药注射剂的使用存在部分不合理问题,应在今后的工作中持续改进。

环保型真空清洗技术在热处理中的应用

清洗是零件热处理前和热处理后必不可少的一道辅助工序,航空领域对零件的热处理质量要求更为严格,热处理清洗的效果好坏会直接影响到零件的使用性能、质量、寿命以及一致性与可靠性等。针对传统清洗工艺清洗效果差、污染环境和危害人身安全等问题,环保型有机溶剂真空清洗技术采用洗净能力强且可循环再生的碳氢溶剂/改性醇作为清洗剂,结合真空清洗和超声清洗,可提高零件表面质量,提升清洗效率,减少污染物排放,实现绿色高效清洗。

整车企业挥发性有机物(VOCs)全流程治理的研究与实践

汽车制造业是挥发性有机物(VOCs)的主要工业排放源之一,加强汽车生产环节VOCs的治理,对于促进大气生态环境质量持续改善具有重要作用,对推动汽车制造业绿色转型高质量发展具有重要的战略和现实意义。本文在研究和实践的基础上,提出了整车企业全流程的VOCs治理方案,包含源头替代减量、过程控制优化、末端治理保障、数字化赋能持续改善等四个集成的环节。介绍了VOCs全流程治理方案四个环节的主要工作方法和关键技术,以及应用这些方法和技术进行VOCs治理所取得的实际效果。

Enrichment of copper and recycling of cyanide from copper–cyanide waste by solvent extraction

The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper–cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.

Nickel solvent extraction from cold purification filter cakes of Angouran mine concentrate using LIX984N

Cold purification filter cakes generated in the hydrometallurgical processing of Angouran mine zinc concentrate commonly contain significant amounts of Zn, Cd, and Ni ions and thus are valuable resources for metal recovery. In this research, a nickel containing solution that was obtained from sulfuric acid leaching of the filter cake following cadmium and zinc removal was subjected to solvent extraction experiments using 10vol%LIX984N diluted in kerosene. Under optimum experimental conditions （pH 5.3, volume ratio of organic/aqueous （O：A） = 2：1, and contact time -5 min）, more than 97.1% of nickel was extracted. Nickel was stripped from the loaded organic by contacting with a 200 g/L sulfuric acid solution, from which 77.7% of nickel was recovered in a single contact at the optimum conditions （pH 1-1.5, O：A =5：1, and contact time =15 min）.

工业废气治理中的吸收和吸收塔工艺设计理论及其应用研究

吸收是气体溶解于液体的一种化工单元操作。它对于气体分解、合成混合气的处理和废气的净化具有重大的实际意义。特别是环境保护的需要提出大量新的任务,因而要求不断发现新的分离方法。重点介绍工业废气治理中的吸收和吸收塔的工艺设计理论及其实践运用。

热处理前溶剂活化对芳香聚酰胺反渗透膜结构的影响机制

热处理前对芳香聚酰胺反渗透膜进行溶剂活化(或称润洗)是一类提高膜透过性的手段.普遍认为,在热处理前溶剂活化的过程中,芳香聚酰胺层内残留的芳香聚酰胺低聚物将溶于溶剂且溶剂可溶胀重整聚酰胺层,因而膜结构与性能发生变化.然而,热处理前溶剂活化多使用非极性溶剂,这类溶剂与芳香聚酰胺的溶解度参数相差较大,对芳香聚酰胺层的溶胀与溶解作用均较弱,因此,热处理前溶剂活化引起的膜结构改变不能完全归因于非极性溶剂与膜的相互作用.近期有研究表明,芳香聚酰胺层内残留物可在水中溶出,推测热处理前溶剂活化可能通过影响残留物在水中的溶出而改变膜结构.基于此,进一步探究热处理前溶剂活化对膜结构的影响机制.对比了水浸泡前后的膜结构与性能,分析了活化膜与未活化膜在水中溶出物质的紫外-可见光谱,对比了未活化膜和活化膜的结构与性能.结果表明,热处理后芳香聚酰胺层内仍有大量易溶于水的亲水性残留物.热处理前利用正己烷对膜进行溶剂活化可除去未反应单体及低聚物,削弱热处理过程中聚酰胺层的进一步交联,加剧芳香聚酰胺层内亲水性残留物在水中的溶出.因此,活化后的膜分离层厚度、粗糙度和分离层内酰胺含量均降低,膜透过性提升.本工作完善了热处理前溶剂活化对膜结构的影响机制.

CO_2 selective hydrogenation to synthetic natural gas(SNG) over four nano-sized Ni/ZrO_2 samples:ZrO_2 crystalline phase & treatment impact

Two type zirconia (monoclinic and tetragonal phase ZrO2) carriers were synthesized via hydrothermal route, and nano-sized zirconia supported nickel catalysts were prepared by incipient impregnation then followed thermal treatment at 300 °C to 500 °C, for the CO2selective hydrogenation to synthetic natural gas (SNG). The catalysts were characterized by XRD, CO2-TPD-MS, XPS, TPSR (CH4, CO2) techniques. For comparison, the catalyst NZ-W-400 (monoclinic) synthesized in water solvent exhibited a better catalytic activity than the catalyst NZ-M-400 (tetragonal) prepared in methanol solvent. The catalyst NZ-W-400 displayed more H2absorbed sites, more basic sites and a lower temperature of initial CO2activation. Then, the thermal treatment of monoclinic ZrO2supported nickel precursor was manufactured at three temperature of 350, 400, 500 °C. The TPSR experiments displayed that there were the lower temperature for CO2activation and initial conversion (185 °C) as well as the lower peak temperature of CH4generation (318 °C), for the catalyst calcined at 500 °C. This sample contained the more basic sites and the higher catalytic activity, evidenced byCO2-TPD-MS and performance measurement. As for the NZ-W-350 sample, which exhibited the less basic sites and the lower catalytic activity, its initial temperature for CO2activation and conversion was higher (214 °C) as well as the higher peak temperature of CH4formation (382 °C). © 2016 Science Press

木质纤维素选择性提取松柏醇和芥子醇

木质素是一种可再生的芳香聚合物,可生产精细化学品。然而,由于木质素复杂的化学结构,及解聚单体的衍生化和深度裂解,当前木质素解聚利用普遍存在产物复杂等问题。选择性断裂木质素连接键,对提高产物选择性、实现木质素分级利用有一定意义。基于有机溶剂/水木质素提取体系,不使用外加催化剂,选择性裂解原本木质素中的酯键提取松柏醇和芥子醇。研究结果表明,乙醇在温和条件下可以有效地断裂肉桂酸苯乙酯和苯乙酸苯酯酯键模型物,但对苯氧基乙苯的β-O-4醚键不产生影响。当以木粉为底物时,单酚产物以松柏醇和芥子醇为主,在二氧六环/水体积比9∶1溶剂体系的作用下,230℃反应0.5 h的总收率最高,可达57.57 mg/g,选择性为62.88%.不同来源生物质在此体系下也表现出良好的收率和选择性。

碘三离子后处理对钙钛矿太阳电池的影响研究

采用碘三离子(I3-)作为提升钙钛矿太阳电池性能的界面修饰材料,对钙钛矿体相及上层空穴传输材料的接触界面进行修饰和改性,钝化光活性层上表面缺陷,以优化光电转换器件的转换效率。由反溶剂法和后处理的形式,制备平面异质结电池,运用该界面钝化策略改善后的器件效率达到18.9%,且电池的稳定性也得到增强,600 h后仅有5%的性能衰减。通过物相和光电性质等表征与测试,系统地研究电池的形貌及性能参数,探究不同浓度的I3-对器件性能的影响作用和机理。研究发现,该缺陷钝化策略对钙钛矿膜层进行处理后,能有效改善钙钛矿材料的结晶性,减少其表面陷阱态缺陷,降低钙钛矿与空穴传输层的载流子界面传输势垒,且I3-与钙钛矿能形成钝化层,起到隔绝水氧的作用,使其稳定性得到改善。