共沉淀法制备Ag/AgCl-TiO2空心复合纳米微球及其光催化性能

通过甲基丙烯酸与苯乙烯聚合制备了表面负电性的聚苯乙烯(PSt)纳米乳胶粒. 在乙醇与水的混合溶剂中, 用硅烷偶联剂乙烯基三甲氧基硅烷对其进行表面改性后加入钛酸四丁酯、 氯化钠和硝酸银, 以PSt乳胶粒为模板采用共沉淀法制备了PSt-AgCl-TiO₂复合微球. 在180 ℃对其进行液相预处理及煅烧去除PSt模板后制备了Ag/AgCl-TiO₂空心复合粒子. 对各阶段产物的形貌、 晶体结构和比表面积等进行了表征. 结果表明, 所得产物为Ag/AgCl与锐钛矿型TiO₂复合的空心粒子, 其比表面远大于商品TiO₂(P25). 考察了Ag/AgCl-TiO₂复合粒子在紫外光与可见光下对罗丹明B(RhB)降解的催化活性. 结果表明, 在紫外光下n(Ag)/n(Ti)=0.1%的Ag/AgCl-TiO₂复合粒子活性最高, 30 min时对RhB的降解率比不含Ag/AgCl的TiO₂空心微球提高了13%; 虽然Ag/AgCl-TiO₂在可见光下的催化活性远比紫外光下低, 但与纯TiO₂空心纳米微球相比其催化活性仍明显增强. n(Ag)/n(Ti)=2.0%的Ag/AgCl-TiO₂复合粒子催化活性最高, 120 min时对RhB的降解率比不含Ag/AgCl的TiO₂空心微球提高了38%.     

无电沉积高密度钯金属纳米线阵列

利用介孔氧化硅薄膜作为模板,通过无电沉积路线在介孔薄膜孔道内合成了高密度钯金属纳米线阵列.利用介孔薄膜导向剂的疏水区作为载体,引进钯金属疏水化合物并经热解和还原,得到钯微粒,以此为催化中心引发无电沉积,避免了传统无电沉积复杂的工艺过程.结果表明,纳米线尺寸均一,长径比大于60,完全填充了介孔薄膜的孔道,并可通过介孔模板孔径的选择对纳米线直径加以调控.     

Microwave-assisted fast and efficient synthesis of some crown ethers

13-Crown-4,16-crown-5,dibenzo-12-crown-4 and dibenzo-14-crown-4 were synthesized by a one-pot microwave-assisted procedure in good yields.Irradiation of diols and dichlorides in the presence of sodium hydroxide in DMSO gave title crown ethers presumably within a template effect.     

A conversion route towards tubular SiO2 using rod-like BaSiF6 as a novel template

A simple hydrothermal reaction between Ba(NO₃)₂ and K₂SiF₆ results in the formation of 1D rod-like BaSiF₆. The BaSiF₆ rods can act as efficient precursors for production of tubular SiO₂ by hydrothermal reaction in alkaline solutions. Powder X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM), high resolution electron microscopy (HRTEM), and field emission scanning electron microscopy (FESEM) were used to characterize the phase and morphology of the final product. The experiments indicated the amount of NaOH, reaction temperature, and reaction time played important roles in the transformation process. A possible growth mechanism of tubular silica was proposed.     

Solvothermal Synthesis,Crystal Structure and Properties of the First Organic‐templated Holmium Sulfate [C2N2H10]3[Ho2(SO4)6·2H2O]

The first organic amine‐templated holmium sulfate [C₂N₂H₁₀]₃[Ho₂(SO₄)₆·2H₂O] ( 1 ) has been synthesized solvothermally and has been structurally characterized by single‐crystal X‐ray diffraction studies, IR spectroscopic, thermogravimetric (TG) and inductivity coupled plasma (ICP) measurements. Crystal analyses of compound 1 showed a novel inorganic layer constructed from the zigzag and helical [–Ho–O–S–O–]_n chains, both of the chains are connected by μ‐2 SO₄^2– groups to form 10‐membered rings. The solvent plays an important role during the formation of 1 .     

Multidentate carborane-containing Lewis acids and their chemistry: mercuracarborands

Macrocyclic Lewis acidic hosts with structures incorporating electron-withdrawing icosahedral carboranes and electrophilic mercury centers bind a variety of electron-rich guests. These compounds, the so-called mercuracarborands, are synthesized by a kinetic halide ion template effect that affords tetrameric cycles or in the absence of halide ion templates, cyclic trimers. Both types of mercuracarborands form stable host–guest complexes with anionic and neutral electron-rich molecules. The multidentate structure of mercuracarborand hosts has made these unique molecules ideal for catalytic and ion-sensing applications as well as for the assembly of supramolecular architectures.     

聚烯丙基氯化铵模板存在下丙烯酰胺-丙烯酸共聚合反应动力学研究

丙烯酰胺 (AM)和丙烯酸 (AA)模板共聚合是以聚烯丙基氯化铵 (PAAC)模板存在下 ,在水溶液中进行 ,在这体系中 ,模板PAAC和单体AA有很强的相互作用 ,而单体AM与模板则没有作用 .应用膨胀计和电导滴定方法研究了影响聚合反应速度的各种因素 ,得到的结果指出 ,在聚烯丙基铵模板作用下共聚合反应遵循Ⅰ型 (zip)模板聚合反应机制 ,速度最高值出现在模板单元T与单体AA等摩尔比 (T AA =1)处 ,这表明在反应溶液中PAAC和单体AA具有很强的相互作用 .测得它们的竞聚率分别为r1 =2 6 8(AA)和r2 =0 4 4 (AM) ,与没有模板存在时相比 ,大幅度增高的r1 值表明此共聚合反应 ,生成AA长序列结构的可能性大大增加 .同时发现聚合反应速度分别和单体浓度及引发剂浓度的 1 1和 0 83次方成正比 ,由于模板的作用数值高于常规值 .     

模板组装Fe纳米线阵列及其微结构

铝在硫酸溶液中经直流阳极氧化,得到多孔铝阳极氧化膜(AAO). 以AAO膜为模板,通过交流电沉积的方法,在AAO模板孔内成功组装了Fe纳米线.TEM分析表明,Fe纳米线的长度约为2.5 μm,其长度分布十分均匀；粗细均匀,直径约为25 nm. XRD实验分析证实,所制备的Fe纳米线为α-Fe.选区电子衍射（SAED）实验分析表明,α-Fe纳米线具有单晶结构.     

微反应器和微聚合反应器

微反应器是指容量仅为零点几μm^3或宽度为1μm左右的反应“容器”，反应在这个微小区域内有控地进行。以表面科学与微制造技术为核心，新型微反应器近年来发展很快。本文介绍五种微反应器，即反相胶束微反应器，聚合物微反应器，固体模板微反应器，微条纹反应器和微聚合反应器，以及它们在各高科技领域中的可能应用。     

DNA模板诱导针状CdS纳米粒子的形成

利用生物分子作为模板合成无机纳米粒子 ,可以精确地控制生成粒子的结构、大小、形状等 ,这方面的工作已经引起了研究者的广泛关注[1].目前 ,已经对许多生物分子作为无机纳米粒子合成模板剂的可行性进行了探索 .Ｍａｎｎ等[2 ]利用蛋白质作为模板合成ＣｄＳ纳米粒子 ;Ｗａｎｇ等[3]利用哺乳类眼睛晶状体管蛋白作为模板合成纳米尺寸的ＣｄＳ粒子 ;Ｂｒａｕｎ等[4 ]将寡聚核苷酸连接在两个金电极之间 ,用ＤＮＡ分子作为模板生长出长 1 2 μｍ、直径 1 0 0ｎｍ的银纳米线 ;Ｓｈｅｎｔｏｎ等[5 ]用烟草斑纹病毒的蛋白外壳作模板剂诱导生成无机 …