碱处理浓度对预脱铝ZSM-5成孔过程及其MTG反应性能的影响

在80℃水浴条件下,对ZSM-5分子筛进行酸碱处理改性;重点考察了碱处理溶液浓度对酸预处理脱铝后ZSM-5分子筛微观结构及其催化甲醇制汽油(MTG)性能的影响。通过BET、XRD、FT-IR、NH₃-TPD和TEM等手段对样品进行表征。结果表明,单独酸处理没有改变分子筛孔结构,单独碱处理产生了并不明显的介孔。酸预处理后再碱处理可促进介孔的产生,产生更为显著的介孔结构;而且随着碱处理强度的增加,分子筛样品的介孔/微孔比表面积比例和孔体积均先增大后降低。酸浓度2mol·L^-1,碱浓度0.4mol·L^-1条件处理得到的分子筛,介孔比表面积比例和孔容均达到最大,酸量和酸强度最低。在400℃,0.1MPa,WHSV=2.1h^-1条件下,甲醇制汽油反应性能最佳:汽油收率由未改性时的30wt%提高到34wt%,寿命更是由16h延长到135h,芳烃含量由原来的73wt%降至20wt%。     

碱处理浓度对预脱铝ZSM-5成孔过程及其MTG反应性能的影响

在80℃水浴条件下,对ZSM-5分子筛进行酸碱处理改性;重点考察了碱处理溶液浓度对酸预处理脱铝后ZSM-5分子筛微观结构及其催化甲醇制汽油(MTG)性能的影响。通过BET、XRD、FT-IR、NH₃-TPD和TEM等手段对样品进行表征。结果表明,单独酸处理没有改变分子筛孔结构,单独碱处理产生了并不明显的介孔。酸预处理后再碱处理可促进介孔的产生,产生更为显著的介孔结构;而且随着碱处理强度的增加,分子筛样品的介孔比表面积比例和孔体积均先增大后降低。酸浓度2 mol·L^-1,碱浓度0.4 mol·L^-1条件处理得到的分子筛,介孔比表面积比例和孔容均达到最大,酸量和酸强度最低。在400℃,0.1 MPa,WHSV=2.1 h^-1条件下,甲醇制汽油反应性能最佳:汽油收率由未改性时的30wt%提高到34wt%,寿命更是由16 h延长到135 h,芳烃含量由原来的73wt%降至20wt%。     

Metal‐Supported Aluminosilicate Ultrathin Films as a Versatile Tool for Studying the Surface Chemistry of Zeolites

The application of a variety of “surface‐science” techniques to elucidate surface structures and mechanisms of chemical reactions at zeolite surfaces has long been considered as almost impossible because of the poor electrical and thermal conductivity of those materials. Here, we show that the growth of a thin aluminosilicate film on a metal single crystal under controlled conditions results in adequate and well‐defined model systems for zeolite surfaces. In principle, silicate films that contain metals other than Al (e.g. Ti, Fe, etc) may be prepared in a similar way. We believe that this approach opens up a new playground for experimental and theoretical modeling of zeolites, aimed at a fundamental understanding of structure–reactivity relationships in such materials.     

材料基因工程技术在分子筛领域中的应用

材料基因工程是近年来材料领域兴起的前沿技术, 其基本理念是融合材料高通量计算、 高通量实验和数据技术加速新材料的设计和研发. 分子筛作为一种重要的化工材料, 因其良好的热稳定性、 较高的比表面积、 独特的孔道结构及可调变的元素组成和酸性, 在气体吸附、 分离、 异相催化和离子交换等工业领域应用广泛. 近年来, 融合高通量计算、 高通量实验和数据库技术的材料基因工程技术正逐步应用于分子筛研发等领域: 高通量计算能够从理论上预测并筛选出具有优异性能的分子筛合成目标、 高通量实验显著提升了分子筛材料合成与表征的效率、 数据库技术则为未来挖掘分子筛材料的合成规律与构效关系奠定了数据基础. 本文主要从这3个方面阐述材料基因工程技术在分子筛材料研发领域的应用及进展, 总结以功能为导向、 定向设计和构筑分子筛材料所面临的机遇与挑战, 并对材料基因工程技术在分子筛领域的前景进行了展望.     

Tuning of the Temperature Window for Unit‐Cell and Pore‐Size Enlargement in Face‐Centered‐Cubic Large‐Mesopore Silicas Templated by Swollen Block Copolymer Micelles

The unit‐cell size and pore diameter as functions of temperature are investigated in the syntheses of FDU‐12 silicas with face‐centered cubic structure templated by Pluronic (PEO‐PPO‐PEO) block copolymer micelles swollen by toluene. The temperature range in which the unit‐cell size and pore size strongly increase as temperature decreases is correlated with the critical micelle temperature (CMT) of the surfactant. While Pluronic F127 affords a wide range of unit‐cell parameters (28–51 nm) and pore diameters (16–32 nm), it renders moderately enlarged pore sizes at 25 °C. The use of Pluronic F108 with higher CMT affords FDU‐12 with very large unit‐cell size (～49 nm) and large pore diameter (27 nm) at 23 °C. Large unit‐cell size (40–41 nm) and pore size (22 nm) were obtained even at 25 °C. The application of Pluronics F87 and F88 with much smaller molecular weights and higher CMTs also allows one to synthesize FDU‐12 with quite large unit‐cell parameters and pore sizes at room temperature. The present work demonstrates that one can judiciously select Pluronic surfactants with appropriate CMT to shift the temperature range in which the pore diameter is readily tunable.     

组织工程相关生物材料表面工程的研究进展

生物材料用作人工细胞外基质(ECM ) 在组织工程中占据重要位置。本文在分析细胞2生物材料表面相互作用的基础上, 从生物材料中的水、材料表面的形态、材料表面的特异性识别及生物材料诱发愈合等方面探讨了生物材料的复杂性。生物材料对细胞的影响是一个双向、动态过程, 起着调节细胞增殖和凋亡平衡的作用。基于生物材料对细胞生长的影响, 本文提出了生物材料表面生物仿生化以提高细胞亲和力,糖链团簇、糖脂质及材料表面蛋白质修饰以提高细胞特异性识别, 材料表面的自组装修饰以改善表面形态等观点。     

Dimension Engineering in Noble-Metal-Based Electrocatalysts for Water Splitting

Dimension engineering plays a critical role in determining the electrocatalytic performance of catalysts towards water electrolysis since it is highly sensitive to the surface and interface properties. Bearing these considerations into mind, intensive efforts have been devoted to the rational dimension design and engineering, and many advanced nanocatalysts with multidimensions have been successfully fabricated. Aiming to provide more guidance for the fabrication of highly efficient noble-metal-based electrocatalysts, this review has focused on the recent progress in dimension engineering of noble-metal-based electrocatalysts towards water splitting, including the advanced engineering strategies, the application of noble-metal-based electrocatalysts with distinctive geometric structure from 0D to 1D, 2D, 3D, and multidimensions. In addition, the perspective insights and challenges of the dimension engineering in the noble-metal-based electrocatalysts is also systematically discussed.     

微藻高油脂化基因工程研究策略

石化能源危机与全球气候变化已成为人类的两大重要难题。生物柴油作为可替代普通柴油的环境友好且可再生的能源受到普遍关注。相比植物油和动物脂肪生产,藻类油脂产率高且容易培养,被认为是未来生物柴油发展的重要原料之一。通过转基因技术强化油脂代谢途径,提高富油微藻含油量,已经成为新的研究热点。已有植物研究表明,增强甘油酯酰基转移酶表达,可以提高Kennedy途径代谢中间体通量,从而增加甘油三酯(TAG)的积累。本文综述了微藻油脂代谢途径的国内外研究现状和提高油脂积累的代谢调控策略;详细阐述了基于植物油脂合成强化的成功经验,通过增强微藻Kennedy途径对提高TAG生物合成的重要作用;讨论了当前转基因微藻的遗传转化方法及其需要解决的关键性科学技术问题;分析了基因工程技术调控微藻脂类代谢途径生产高油脂的可能性,并对该研究的发展进行了展望。     

粒子沥滤法制备组织工程用多孔支架的研究进展

粒子沥滤法作为常用的制备组织工程支架的方法,这种方法对实验设备和实验条件要求较低,孔隙率、孔径可控。但传统的溶液浇铸/粒子沥滤法也存在一些缺点,只适合制备薄层支架,孔-孔连通性不好,聚合物有可能保留致孔剂和/或有毒溶剂。本文总结了近几年科研工作者对这种方法所进行的改进工作,并探讨了改进的效果和不足。     

地方本科院校化工类专业导论课探索与实践

针对地方高校化工类新生对专业认知模糊、发展方向不明确、行业认识存在误区、学习方法迷茫等现状,论述了开设化工类专业导论课的必要性及意义,提出了应从教学内容、教学方法手段、教学评价等3个方面增强专业导论课的实效性,对于大学新生的专业教育具较强的针对性和借鉴意义。     

Recent Advances in DNA-Based Cell Surface Engineering for Biological Applications

Due to its excellent programmability and biocompatibility, DNA molecule has unique advantages in cell surface engineering. Recent progresses provide a reliable and feasible way to engineer cell surfaces with diverse DNA molecules and DNA nanostructures. The abundant form of DNA nanostructures has greatly expanded the toolbox of DNA-based cell surface engineering and gave rise to a variety of novel and fascinating applications. In this review, we summarize recent advances in DNA-based cell surface engineering and its biological applications. We first introduce some widely used methods of immobilizing DNA molecules on cell surfaces and their application features. Then we discuss the approaches of employing DNA nanostructures and dynamic DNA nanotechnology as elements for creating functional cell surfaces. Finally, we review the extensive biological applications of DNA-based cell surface engineering and discuss the challenges and prospects of DNA-based cell surface engineering.     

Concurring Chalcogen- and Halogen-Bonding Interactions in Supramolecular Polymers for Crystal Engineering Applications

The engineering of crystalline molecular solids through the simultaneous combination of distinctive non-covalent interactions is an important field of research, as it could allow chemist to prepare materials depicting multi-responsive properties. It is in this context that, pushed by a will to expand the chemical space of chalcogen-bonding interactions, a concept is put forward for which chalcogen- and halogen-bonding interactions can be used simultaneously to engineer multicomponent co-crystals. Through the rational design of crystallizable molecules, chalcogenazolo pyridine scaffold (CGP) modules were prepared that, bearing either a halogen-bond acceptor or donor at the 2-position, can interact with suitable complementary molecular modules undergoing formation of supramolecular polymers at the solid state. The recognition reliability of the CGP moiety to form chalcogen-bonded dimers allows the formation of heteromolecular supramolecular polymers through halogen-bonding interactions, as confirmed by single-crystal X-ray diffraction analysis.     

Recent Strategies in Fabrication of Gradient Hydrogels for Tissue Engineering Applications

Hydrogels are widely used as scaffold in tissue engineering field because of their ability to mimic the cellular microenvironment. However, mimicking a completely natural cellular environment is complicated due to the differences in various physical and chemical properties of cellular environments. Recently, gradient hydrogels provide excellent heterogeneous environment to mimic the different cellular microenvironments. To create hydrogels with an anisotropic distribution, gradient hydrogels have been widely developed by adopting several gradient generation techniques. Herein, the various gradient hydrogel fabrication techniques, including dual syringe pump systems, microfluidic device, photolithography, diffusion, and bio‐printing are summarized. As the effects of gradient 3D hydrogels with stems have been reviewed elsewhere, this review focuses principally on gradient hydrogel fabrication for multi‐model tissue regeneration. This review provides new insights into the key points for fabrication of gradient hydrogels for multi‐model tissue regeneration.     

理科化学专业化学工程基础课程的复习课教学

在讲授化学工程基础课程中,通过复习课的形式帮助学生总结课程中的共性规律和方法,将其分为理想化方法、物料衡算、能量衡算、因次分析法、分类研究法、图解法、边界层理论、操作极限、对数平均值等内容,并增加不同单元的典型例题巩固已授内容,提高了学生的认识深度,收到了较好的教学效果。     

Electrospinning of Hyperbranched Poly-L-Lysine/Polyaniline Nanofibers for Application in Cardiac Tissue Engineering

Electrospun polyaniline nanofibers are one of the most promising materials for cardiac tissue engineering due to their tunable electroactive properties. Moreover, the biocompatibility of polyaniline nanofibes can be improved by grafting of adhesive peptides during the synthesis. In this paper, we describe the biocompatible properties and cardiomyocytes proliferation on polyaniline electrospun nanofibers modified by hyperbranched poly-L-lysine dendrimers (HPLys). The microstructure characterization of the HPLys/polyaniline nanofibers was carried out by scanning electron microscopy (SEM). It was observed that the application of electrical current stimulates the differentiation of cardiac cells cultured on the nanofiber scaffolds. Both electroactivity and biocompatibility of the HPLys based nanofibers suggest the use this material for culture of cardiac cells and opens the possibility of using this material as a biocompatible electroactive 3-D matrix in cardiac tissue engineering.     

Advances in Polymeric Systems for Tissue Engineering and Biomedical Applications

The characteristics of tissue engineered scaffolds are major concerns in the quest to fabricate ideal scaffolds for tissue engineering applications. The polymer scaffolds employed for tissue engineering applications should possess multifunctional properties such as biocompatibility, biodegradability and favorable mechanical properties as it comes in direct contact with the body fluids in vivo. Additionally, the polymer system should also possess biomimetic architecture and should support stem cell adhesion, proliferation and differentiation. As the progress in polymer technology continues, polymeric biomaterials have taken characteristics more closely related to that desired for tissue engineering and clinical needs. Stimuli responsive polymers also termed as smart biomaterials respond to stimuli such as pH, temperature, enzyme, antigen, glucose and electrical stimuli that are inherently present in living systems. This review highlights the exciting advancements in these polymeric systems that relate to biological and tissue engineering applications. Additionally, several aspects of technology namely scaffold fabrication methods and surface modifications to confer biological functionality to the polymers have also been discussed. The ultimate objective is to emphasize on these underutilized adaptive behaviors of the polymers so that novel applications and new generations of smart polymeric materials can be realized for biomedical and tissue engineering applications.

     

高职化工类专业“双师型”教师量化评价体系的构建

建设高素质的“双师型”师资队伍是保证高职教育教学质量的关键。首先分析了化工类专业的人才培养目标与所必须具备的专业能力,由此确定了化工类专业双师素质教师的专业核心能力及支撑专业核心能力的主干课程,进一步建立了高职化工类专业“双师型”教师量化评价体系,为高职化工类双师型教师的引进、培养、评价和管理提供了参考依据。     

新工科背景下湖南大学应用化学专业的改革与建设

It is necessary to develop new engineering-directed applied chemistry major on the basis of chemistry major and to remodel the current applied chemistry education according to the concept of emerging engineering. Herein, emendation in 2020 version of applied chemistry education plan and researches on teaching renovations for applied chemistry major in Hunan University is introduced. Through the adjustments of education goals, course systems, teaching contents and teaching models, we wish to highlight the central status of the educations that integrates morality and ability. In addition to the inheritance of the specialty in corrosion and protection, it is expected to further satisfy the need of graduates for the industries such as new materials, new energy, high-tech production, environmental protection, and new generation of information technique. At last, future trends and perspectives in emerging engineering applied chemistry is proposed.     

组织工程三维多孔支架的制备方法和技术进展

组织工程的关键技术之一在于将具有良好生物相容性和生物降解吸收性能的生物材料制备成具有特定形状和相连孔结构的三维多孔细胞支架（细胞外基质替代物）。本文着眼于多孔支架制备方法分别与多孔支架孔结构和外形的内在联系，从致孔和外形成型两个层次对组织工程多孔支架的制备方法和技术新近的研究进展进行了综述。     

新经济时代应用化学专业人才精细化工方向课程体系设计研究

新经济时代对应用化学专业人才精细化工方向课程体系提出了新的要求,从分析建设精细化工课程体系的价值入手,对精细化工方向教育的现状进行了研究,从理念维度、课程组织维度、培养目标、培养主体需求维度对精细化工方向课程体系提出了设计设想。同时也从这4个维度出发提出了相应的实现路径,以期促进精细化工专业课程体系更加适应新经济时代的要求。