Molecularly imprinted polymer/graphene oxide modified glassy carbon electrode for selective detection of sulfanilamide

A novel sensitive electrochemical sensor based on a glassy carbon electrode(GCE) modified with molecularly imprinted polymer(MIP) and grapheme oxide(GO) was developed.The MIP/GO material was prepared by precipitation polymerization in the presence of sulfanilamide as template molecule.The MIP/GO based electrochemical sensor was characterized using scanning electron microscopy(SEM),cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS) and square wave voltammetry(SWV).The results indicated that the sensor exhibited good affinity and excellent electrochemical response for sulfanilamide.Under optimized conditions,the oxidation peak current intensity of sulfanilamide showed two linear dynamic ranges from 10 to 1000 ng mL~(-1),and the standard deviation was less than 5% using SWV method.The sensor displays good stability,reproducibility,and high sensitivity.It can be further applied to quantify sulfanilamide in milk.     

石墨烯对气压烧结WC-Co硬质合金性能的影响

为了减小氧化石墨烯（graphene oxide,GO）在WC-10Co硬质合金中的团聚以及高温液相烧结过程中Co对GO的溶蚀作用,通过化学镀的方式制备了改性氧化石墨烯（GO/Ni）,随后利用静电吸附以及机械搅拌两种方法分别制备了WC-10Co-GO复合粉体和WC-10Co-GO/Ni复合粉体。用扫描电子显微镜（scanning electron microscope,SEM）和透射电子显微镜(transmission electron microscope,TEM)对改性后的GO以及复合粉体进行微观形貌的表征。采用气压烧结工艺制备了WC-10Co、WC-10Co-GO和WC-10Co-GO/Ni硬质合金并研究了硬质合金的物理性能和力学性能。实验结果表明：随着GO和GO/Ni的加入,硬质合金的密度和洛氏硬度有了略微的降低;对比WC-10Co硬质合金,WC-10Co-GO和WC-10Co-GO/Ni硬质合金的横向断裂强度分别提升了35.2%和59.7%,其中GO/Ni作为作为基体增强相的效果最佳。     

氧化石墨烯尺寸分级及细胞毒性研究进展

氧化石墨烯（graphene oxide, GO）是一种化学改性的石墨烯材料。作为化学法制备石墨烯的前驱产物,GO具有石墨烯固有的优异性能外,大量含氧官能团的存在还使其表现出两亲性,例如在诸多溶剂（尤其是水）中分散性能良好。不同尺寸的GO应用于不同领域。大尺寸GO因其结构完整,适用于于制备导电薄膜和整料。小尺寸GO因其优异的生物相容性和生物活性,常应用于生物医学领域。制备不同尺寸级别的GO,使其在不同领域中的应用发挥更好的作用很有必要。简单介绍了GO的制备方法及结构特性,重点总结了影响GO尺寸的因素、GO的尺寸分级方法以及GO细胞毒性的尺寸效应。     

Microstructures and properties of Al<Subscript>2</Subscript>O<Subscript>3</Subscript> dispersion-strengthened copper alloys prepared through different methods

Al₂O₃ dispersion copper alloy powder was prepared by internal oxidation, and three consolidation methods—high-velocity compaction (HVC), hot pressing (HP), and hot extrusion (HE)—were used to prepare Al₂O₃ dispersion-strengthened copper (Cu–Al₂O₃) alloys. The microstructures and properties of these alloys were investigated and compared. The results show that the alloys prepared by the HP and HE methods exhibited the coarsest and finest grain sizes, respectively. The alloy prepared by the HVC method exhibited the lowest relative density (98.3% vs. 99.5% for HP and 100% for HE), which resulted in the lowest electrical conductivity (81% IACS vs. 86% IACS for HP and 87% IACS for HE). However, this alloy also exhibited the highest hardness (77 HRB vs. 69 HRB for HP and 70 HRB for HE), the highest compressive strength (443 MPa vs. 386 MPa for HP and 378 MPa for HE), and the best hardness retention among the investigated alloys. The results illustrate that the alloy prepared by the HVC method exhibits high softening temperature and good mechanical properties at high temperatures, which imply long service life when used as spot-welding electrodes.     

石墨烯负载Zn2GeO4光催化剂的制备及其 降解有机污染物的性能研究

采用溶剂热法制备Zn_2Ge O_4纳米晶;并将其负载到氧化石墨烯(GO)上。通过两步水热法制备了一系列Zn_2Ge O_4/GO复合光催化剂。利用X-射线衍射(XRD)、透射电子显微镜(TEM)、紫外可见吸收光谱(UV-Vis)等手段对催化剂的结构、形貌及光学性能进行了表征;并以罗丹明B(Rh B)作为目标降解污染物,对其进行了光催化性能测试。结果表明,Zn_2Ge O_4纳米晶均匀地分散在GO上,与单纯的Zn_2Ge O_4纳米晶相比,Zn_2Ge O_4/GO复合物的光催化性能有了明显的提高。当GO质量分数为5%时,罗丹明B降解率达到95.21%;且经过5次循环使用后,仍然保持较高的光催化活性,具有良好的稳定性。     

玻片表面硅烷/氧化石墨烯复合涂层的制备及其摩擦性能

使用硅烷偶联剂 3-氨丙基甲基二甲氧基硅烷(3-(dimethoxymethylsilyl)propylamine) 和不同氧化程度的氧化石墨烯(graphene oxide, GO)在玻片表面采用浸渍法制备了一种在水环境下具有较好润滑性能的氧化石墨烯涂层. 通过傅里叶变换红外光谱 (Fourier transform infrared spectrometer, FTIR)仪、拉曼光谱(Raman spectra)分析法、水接触角(water contact angle, WCA)测试等方法研究了涂层的表面形貌及其特征. 研究结果表明, 所制备的硅烷/氧化石墨烯涂层表面均一, 没有明显的缺陷. 摩擦测试结果显示, 涂层能够有效提高耐磨性能, 不同氧化程度的氧化石墨烯对抗磨性能有着不同的影响, 氧化程度越高, 抗磨性能越好.     

大粒径氧化石墨及石墨烯的制备与表征

以0.10、0.15、0.18、0.30 mm 4种不同粒径的石墨为原料,采用密闭氧化、氨-水合胼还原法,经过2个控温阶段制备了10~20 μm大粒径氧化石墨(GO)与石墨烯,并通过正交实验、单因素实验优化了制备条件. 测定了GO与石墨烯的傅里叶红外光谱、拉曼光谱及热稳定性.用扫描电镜、X线衍射光谱、原子力显微镜测试了产品的结构与石墨烯片层厚度. 实验结果表明:石墨粒径越小,片层剥离程度越高, GO的产率、热稳定性也均有提高. 石墨烯在800 ℃下残炭率高于80%,剥离层厚度约为1 nm. 本实验研究为制备大粒径GO与石墨烯提供了一种可行的实验方法.     

TEMPO氧化-高压均质联用制备柑橘纳米纤维素及其性质表征

以柑橘皮渣为原料,采用2,2, 6,6-四甲基哌啶-1-氧自由基(TEMPO)介导氧化联合高压均质法制备柑橘纳米纤维素,研究次氯酸钠添加量(5、25、50mmol/g)对柑橘纳米纤维素长径比、形貌结构、理化性能等特性的影响。结果表明:随着次氯酸钠质量摩尔浓度的增加,柑橘纳米纤维素的直径和长度都逐渐缩短,并在50mmol/g时长度[(150.57±24.99)nm]与直径[(2.74±0.29)nm]达到最短。扫描电镜与红外光谱分析结果表明:随着氧化剂质量摩尔浓度的升高,柑橘纤维中的木质素、半纤维素被水解,柑橘纤维表面呈现出越来越粗糙的结构。X射线衍射和热重分析显示:氧化均质处理提高了柑橘纳米纤维素的结晶度和耐热性,且纤维素的Ⅰ型晶型未遭到破坏。理化性质分析表明:氧化均质处理可有效提高柑橘纳米纤维素持水力、持油力、胆固醇吸附力和葡萄糖吸附力,并在次氯酸钠质量摩尔浓度为50mmol/g时表现出最强的吸附力。纳米化的柑橘纤维素具有良好的功能特性,研究以期为柑橘皮渣的再利用提供一定的科学依据。     

Strontium Substituted Nanohydroxyapatite Incorporated 3D Printing Scaffold for Bone Tissue Engineering

The customized implants which are composed of polycaprolactone( PCL) and strontium substituted nanohydroxyapatite( SrHA) were fabricated successfully by using fused deposition modeling( FDM),which is a simple 3 D printing technology for fabricating personalized products. The physical and chemical properties of composite scaffolds were characterized by transmission electron microscopy( TEM), Fourier transform infrared spectroscopy( FTIR), X-Ray diffraction( XRD) and inductively coupled plasma-atomic emission spectroscopy( ICPAES). The results suggested that strontium element was successfully doped into nanohydroxyapatite and all scaffolds showed the homogeneous network structure. Furthermore, the in vitro biocompatibility of the scaffolds was evaluated by cell counting kit-8( CCK-8) assay. The data indicated that the prepared scaffolds exhibited excellent biocompatibility to bone marrow mesenchymal stem cells( BMSCs). Besides,strontium element can be released from PCL-SrHA scaffolds in a sustained manner. Therefore,the 3 D printing PCL-SrHA scaffolds hold great potential for bone tissue engineering.     

氧化石墨烯: 一种用于癌症诊断与治疗的新型纳米试剂

癌症已经成为危害人类健康最大因素之一.将纳米粒子运用于癌症的诊断及治疗具有很大的应用前景.氧化石墨烯（Graphene Oxide, GO）是一种由单层碳原子以蜂窝状排列而成的二维碳纳米材料,同时在其碳平面上及其片状结构边缘分别含有丰富的羟基、环氧基和羧基等基团.因其极好的理化性质,GO已经在多学科领域中受到了广泛关注.本文综述了GO作为一种新型的纳米诊断治疗试剂在癌症研究中的应用.     

聚2，5－二甲氧基苯胺膜电极对抗坏血酸的电催化氧化

聚２，５－二甲氧基苯胺（Ｐ２５ＤＭＡｎ）薄膜电极用电聚合的方法制得．采用循环伏安法研究了酸性溶液中抗坏血酸（ＡＨ２）在Ｐ２５ＤＭＡｎ薄膜电极上的电催化氧化．该薄膜电极对抗坏血酸的氧化有很好的电催化活性．讨论了不同种类负离子存在的情况下制成的薄膜对ＡＨ２氧化的催化特性的影响．光电子能谱图所得的结果也证明了Ｐ２５ＤＭＡｎ薄膜电极上有ＡＨ２反应的物种产生．用旋转圆盘电极研究了催化过程动力学．     

掺铜方法对二氧化钛光催化氧化还原性能的影响

采用浸渍法、水解沉淀法、机械混合法制备了铜掺杂的TiO2光催化剂.利用XRD,XPS,TPR等手段对不同样品进行了表征,以乙酸水溶液的光催化氧化降解及二氧化碳光催化还原为反应探针,对3种催化剂光催化活性进行了评价.结果表明,不同方法掺铜影响催化剂表面性质如吸附氧、元素价态及分布,进而影响光催化性能.吸附氧的性能以及存在合适比例的氧化还原对Cu+/Cu2+导致浸渍法制备的掺铜TiO2光催化剂具有最好的光催化活性.     

Preparation and Application of Water Dispersible Graphene as Antistatic Agent for SMS Nonwovens

In this paper, glucose was used as a green reducing agent and a capping reagent in the synthesis of water dispersible graphene, while using exfoliated graphite oxide （GO） as the precursor with the modified Hummers method. Characterizations of the graphene were conducted by UV-visihle absorption spectroscopy and X-ray diffraction （XRD）. Then the spunlaid-melthlowing-spuulaid （SMS） nonwovens were treated with the graphene solution via pad-dry-cure process. The surface and the antistatic property of the obtained nonwovens were tested. The results showed that O. 1 mg/mL graphene solution exhibited good stability in water. When treated with this solution, the graphene could be evenly dispersed on SMS nonwovens and the nonwovens had an excellent antistatic performance and a high relatively antistatic durability.     

新型AgBr/GO复合催化剂的制备及其可见光催化还原CO2性能的初步研究

 采用液相合成法,在十三烷基三甲基溴化铵（CTAB）辅助下制备具有可见光效应的AgBr/GO复合材料,并考察其在可见光下催化还原CO₂制备碳氢化合物的可行性及催化性能。XRD和TEM结果表明：AgBr纳米颗粒均匀地分散在GO载体表面,有利于光诱导下产生的电荷在AgBr与GO界面间的有效传递。可见光照射下,AgBr/GO复合催化剂还原CO₂生成的甲烷、甲醇、CO和乙醇的产量分别是106.11、64.20、26.53和10.96 μmol·g^-1,明显高于AgBr的催化活性。AgBr/GO在重复使用5次后其光催化还原CO₂的活性基本保持不变,因此AgBr/GO是一种高效的、光化学性质稳定的催化剂。     

Molecularly Imprinted Polymer Based on GO-QDs as Enhanced Fluorescent Nanoscale Device for Specific Recognition of Target Protein

In this work the enhanced molecularly imprinted optosensing material based on graphene oxide-quantum dots （ GO- QDs） was synthesized for highly selective and sensitive specific recognition of the target protein, bovine serum albumin （BSA）. Here, GO was introduced to enhance the efficiency of mass-transfer in recognition of target protein. Molecularly imprinted polymer coated GO-QDs using BSA as template （BMIP-coated GO-QDs ） exhibited a fast mass-transfer speed, which could be ascribed to the high volume of efficient surface area and high target recognition efficiency of the synthesized nanoscale device. Under optimal conditions, it was found that the BSA as target protein could remarkably quench the relative fluorescence intensity of BMIP- coated GO-QDs linearly in a concentration-dependent manner that was best described by a Stern-Volmer equation. The Ksv （Stern- Volmer constant） for template BSA was much higher than bovine hemoglobin （BHb） and lysozyme （Lyz）, implying a highly selective recognition ability of the BMIP-coated GO-QDs to BSA. This enhanced fluorescent nanoscale device may provide opportunities to develop a system that is efficient and effective and has potential in the design of highly effective fluorescent receptor for recognition of target protein in Droteomics studies.     

三溴苯酚系列阻燃剂的合成及其在环氧树脂中的阻燃效果

报道了三溴苯酚系列中三种阻燃剂:2、4、6-三溴苯酚缩水甘油醚、2、4、6-三溴苯酚亚磷酸酯和2、4、6-三溴苯酚磷酸酯的合成方法及其对E-44型环氧树脂的阻燃效果,研究结果表明:上述三种阻燃剂采用本文介绍的合成方法所得产品的产率和纯度都很高,对环氧树脂表现出良好的阻燃效果。同时,还得出在分子结构中同时含有溴、磷两种阻燃元素的2、4、6-三溴苯酚磷酸酯比相应的溴化物和磷化物的混合物阻燃协同效应要好的结论。     

氧化石墨烯对亚甲基蓝废水的絮凝效果研究

以氧化石墨烯（GO）为絮凝剂,以水溶性阳离子型染料亚甲基蓝(MB)为处理对象,研究了GO对MB的絮凝效果,拟突破传统絮凝剂不能有效去除可溶性染料的瓶颈. 通过改进的Hummers法制备了GO,利用SEM、XRD、FT-IR对其进行了表征. 探讨了染料初始质量浓度、絮凝剂投加量、溶液pH以及搅拌时间对絮凝效果的影响,并通过测定GO、MB、反应前后溶液的电位和反应前后物质的红外光谱,分析了可能存在的絮凝机理. 同时,比较了几种常用的无机、有机絮凝剂对MB的絮凝效果. 结果表明:当pH=4,染料初始质量浓度为70 mg/L,絮凝剂投加量为180 mg/L,絮凝时间为9 min时,絮凝效率达到95%. 电性中和对絮凝过程起着主要作用,同时还存在吸附架桥作用. 与其他常用絮凝剂相比,GO具有投加量少、去除率高、pH适用范围广等优点,是一种具有广阔应用前景的絮凝剂.     

Graphene oxide-covered melamine foam utilizing as a hybrid foam toward organic dye removal and recyclability

Graphene-based adsorbents have been attracted extensive interest in recent years. Herein, graphene oxide-covered melamine foam (GO-covered MF) was designed and prepared by a mild submerge-covering method with the support of a super-hydrophilic melamine framework, showing its adsorption performances for various organic dyes. The structure morphology as well as chemical, thermal and mechanical properties of the as-obtained hybrid foam (HF) were further determined for the possible structure changes after covering the GO sheets on the MF framework. Moreover, the HF exhibited an excellent ability for organic dye adsorption application, and which was well fitted in the pseudo-second-order kinetic and Langmuir models corresponding to a chemical adsorption and a mono-layer approach during the adsorption process. The maximum adsorption capacity by using the as-obtained HF corresponded to 258.56 ?mg ?g^?1 (methylene blue), 233.22 ?mg ?g^?1 (Rhodamine B), 206.92 ?mg ?g^?1 (methyl orange), and 184.93 ?mg ?g^?1 (Congo red), which are competitive with that of other graphene-based absorbents. In particular, the HF could be reused without a noticeable degradation of organic dye removal performance. As such, the HF prepared in this study can become an encouraging candidate for practical application owing to the reliable recyclability and low-cost.     

TiO_2/氧化石墨烯复合材料的合成及光催化性能研究

以自制氧化石墨、钛酸丁酯为主要原料,用溶胶-凝胶法制备了TiO2/氧化石墨烯(TiO2/GO)复合材料,采用TEM、XRD对其进行表征。以活性艳红X-3B溶液为模拟废水,研究了该复合材料的光催化降解性能,考察了氧化石墨烯含量、染料初始浓度、催化剂用量等因素对其光催化降解率的影响。结果表明:氧化石墨烯片层上均匀负载着锐钛矿型的TiO2球形颗粒,粒径在10 nm左右;当TiO2/GO复合材料中加入的GO含量为100 mg时光催化活性最好,比相同条件下纯TiO2和TiO2与氧化石墨物理混合物的光催化活性有明显提高;相同条件下,降解率随溶液初始浓度的升高而降低,催化剂用量存在最佳值,100 mg/L的活性艳红X-3B溶液,催化剂用量的最佳值为0.8 g/L,反应60 min后其降解率可达96%。     

Preparation and cytocompatibility of polylactic acid/hydroxyapatite/graphene oxide nanocomposite fibrous membrane

A series of polylactic acid (PLA) based nanocomposite fibrous membranes,including neat PLA,PLA/hydroxyapatite (HA) and PLA/HA/graphene oxide (GO),were fabricated via electrospinning method.The morphology and composition were investigated by scanning electron microscopy (SEM),X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) respectively.The thermal stability was determined by thermogravimetric analysis (TGA).To estimate the cytocompatibility of asprepared PLA/HA/GO fibrous membrane,MC3T3-E1 cells were cultured,and the corresponding cell adhesion and differentiation capability were investigated by fluorescence microscopy,SEM and MTT test.The electrospun ternary PLA/HA/GO membrane exhibited three-dimensional fibrous structure with relatively rough surface morphology,which made itself ideal for cell attachment and proliferation in bone tissue regeneration.The fluorescence microscopy,SEM and MTT test confirmed that the PLA/HA/GO nanocomposite fibrous membrane created a proper environment for the seeding and proliferation of MC3T3-E1 cells.