Bioresponsive Hyaluronic Acid‐Capped Mesoporous Silica Nanoparticles for Targeted Drug Delivery

In this paper, we present a facile strategy to synthesize hyaluronic acid (HA) conjugated mesoporous silica nanoparticles (MSP) for targeted enzyme responsive drug delivery, in which the anchored HA polysaccharides not only act as capping agents but also as targeting ligands without the need of additional modification. The nanoconjugates possess many attractive features including chemical simplicity, high colloidal stability, good biocompatibility, cell‐targeting ability, and precise cargo release, making them promising agents for biomedical applications. As a proof‐of‐concept demonstration, the nanoconjugates are shown to release cargoes from the interior pores of MSPs upon HA degradation in response to hyaluronidase‐1 (Hyal‐1). Moreover, after receptor‐mediated endocytosis into cancer cells, the anchored HA was degraded into small fragments, facilitating the release of drugs to kill the cancer cells. Overall, we envision that this system might open the door to a new generation of carrier system for site‐selective, controlled‐release delivery of anticancer drugs.     

铝柱撑蒙脱石负载纳米金催化剂的结构表征及其CO催化活性研究

以铝柱撑蒙脱石为载体,用沉积沉淀法在其表面负载金属Au后制备了Au负载铝柱撑蒙脱石高效负载型催化剂。以XRD,TEM,XPS等手段对催化剂的结构进行了表征,并研究了铝柱撑蒙脱石负载前后CO催化氧化活性的变化规律。结果证明,Au是以高度分散的状态均匀分布在铝柱撑蒙脱石载体表面,且以Au0和Au3+的混合价态形式存在。CO催化氧化活性表征结果表明,负载后催化剂的催化活性有了显著提高,且其催化活性随着负载量的增加而不断增强,但当负载量增大到一定程度后,其催化活性不再继续增加,且有所下降。     

PdO/TiO2 and Pd/TiO2 Heterostructured Nanobelts with Enhanced Photocatalytic Activity

Heterostructures play an important role not only in the manufacture of semiconductor devices, but also in the field of catalysis. Herein, we report the synthesis of PdO/TiO₂ and Pd/TiO₂ heterostructured nanobelts by means of a simple co‐precipitation method, followed by a reduction process using surface‐modified TiO₂ nanobelts as templates. The as‐obtained heterostructures were characterized by transmission electron microscopy, X‐ray photoelectron spectroscopy, and UV/Vis diffuse reflectance spectroscopy. PdO and Pd nanoparticles with a size of about 1.3 and 1.6 nm were assembled uniformly on the surface of TiO₂ nanobelts, respectively. Compared with TiO₂ nanobelts, PdO/TiO₂ and Pd/TiO₂ hybrid nanobelts exhibit enhanced photocatalytic activity upon UV and visible‐light irradiation. Photoelectrochemical technology was used to study the heterostructure effect on enhanced photocatalytic activity. Our mechanistic investigation revealed that energy‐band matching is the major factor in the observed enhancement of photocatalytic activity.     

评《分岔问题及其计算方法》

本文评述了武际可教授和黄克服教授的著作《分岔问题及其计算方法》。该书从生活中常见的分岔问题出发,概述了各类分岔问题及其研究进展;该书的突出特点是以等价类定义分岔,由此对动力系统的稳定性、局部和全局分岔、静分岔与霍普夫分岔等问题进行了深入的论述,并详细介绍了弧长方法为代表的数值计算方法在求解分岔问题方面的有效性。该书是一本非常值得相关科研工作者学习的参考书。

     

人造岗石废渣合成甲酸钙晶体的工艺研究

以人造岗石废渣为原料,采用中和法合成甲酸钙晶体,分析人造岗石废渣与甲酸的投料量质量比、反应时间、搅拌速度、反应温度对人造岗石废渣利用率的影响,采用扫描电子显微镜、XRD、红外光谱仪进行表征。结果表明,人造岗石废渣合成甲酸钙的最佳工艺条件为:人造岗石废渣与甲酸的投料量质量比为1.0∶1.3、反应温度为50℃、搅拌速度为430 r/min、反应时间为50 min、滴加硫化物沉淀剂的体积为0.15 mL,此时铁离子的去除率为98.77%。对产物甲酸钙采用络合滴定和氧化还原滴定法计算得到甲酸钙的收率为94.20%。结果说明:人造岗石废渣呈现不规则的形状,表面较为光滑;产物呈现八面体的形状,团聚,平均粒径为1μm,说明合成的产物按照一定的晶型逐渐生长成型,结合红外光谱和能谱分析为甲酸钙晶体。     

MicroRNA-Triggered Nanozymes Cascade Reaction for Tumor-Specific Chemodynamic Therapy

Off-target toxicity and insufficient hydroxyl radicals (^.OH) generation limit the further clinical application of nanozymes in chemodynamic therapy (CDT). Herein, we designed and constructed a microRNA-triggered nanozyme cascade platform for enhanced tumor-specific chemodynamic therapy. The nanozyme-based cascade reaction could be triggered successfully by the high expression of microRNA in cancer cells to generate more ^.OH, thus exhibiting excellent tumor-specific therapeutic performance. Our work provides a new dimension for tumor-specific chemodynamic therapy.     

“一氧化碳还原氧化铜”实验的一体化设计

借助物质相互转化的原理,仅在一支试管中设计了一氧化碳还原氧化铜的实验;改进后的实验利用传感器收集实验数据,培养学生严谨的证据意识;从气体制备到尾气的处理,创新实验均体现绿色化学的观念。该实验的一体化设计,药品用量少,操作简单,实验耗时短,现象明显,提高了学生的参与度,提升了实验教学效果。     

高中生微观认识学习中科学本质观的调查研究

帮助学生适当理解科学本质是科学教育的重要目标之一,也是培养学生科学素养的核心成分之一。本研究的目的是了解高中生微观学习中的科学本质观。调查表明,学生的科学本质观基本处于较为朴素的水平,对科学内容的理解基本处于了解的水平,在思维方式上几乎只考虑知识是什么和知识有什么用,很少考虑知识的产生式和合理性。影响学生科学本质观的主要因素是教师因素和课程因素。     

乙烯酮光解途径的从头算研究

本文分别考察了C~2~α方式以及C~3-面内弯曲和C~3 一面外弯曲方式下乙烯酮光解脱氢反应(CH~2CO→H~2+C~2O)的状态相关图. 对由此给出的对称性允许的光解脱氢途径进行了从头算研究.发现最具可能的途径是在C~3-面内弯曲方式中^1A″态势能面上进行的绝热光反应,其能垒高度为263.83KJ.mol^-^1.     

(C6H8N3)+I3-和[(Cu3I4)(C8H17N2)]配体原位合成与结构表征

在溶剂热条件下, 以原位反应为基础合成了两个碘化物(C6H8N3)+I3-(1, C6H8N3=2,3-dihydroimi-dazo[1,2-a]pyrimidin-1-ium, 2,3-二氢咪唑[1,2-α]-嘧啶鎓阳离子)和[(Cu3I4)(C8H17N2)](2, C8H17N2=N-ethyl-4-aza-1-azonia-bicyclo[2.2.2]octane, N-乙基三乙烯二铵阳离子). 用元素分析、粉末X射线衍射及单晶X射线衍射等对化合物进行了表征. 结果表明, 化合物1属于三斜晶系, P1空间群, a=0.74281(15) nm, b=0.84241(17) nm, c=0.9993(2) nm, α=82.02(3)°, β=83.30(3)°, γ=82.92(3)°, V=0.6114(2) nm3. 化合物2属于单斜晶系, P21/c空间群, a=0.68924(14) nm, b=1.0786(2) nm, c=2.2779(5) nm, β=94.84(3)°, V=1.6874(6) nm3. 在两个化合物合成中存在两种不同类型的配体原位合成反应, 即化合物1的2-氨基嘧啶和乙醇的成环反应与化合物2的三乙烯二胺和乙醇的烷基化反应.