Solid chemistry of the Zn/1,2,4-triazolate/anion system: Separation of 2D isoreticular layers tuned by the terminal counteranions X (X=Cl, Br, I, SCN)

An array of 2D isoreticular layers, viz. [Zn(atrz)X]_∞ (1·X; X=Cl⁻, Br⁻, I⁻; atrz=3-amino-1,2,4-triazole anion), [Zn₄(atrz)₄(SCN)₄·H₂O]_∞ (1·SCN·H₂O) and [Zn(trz)X]_∞ (2·X; X=Cl⁻, Br⁻, I⁻; trz=1,2,4-triazole anion), have been hydrothermally synthesized and structurally characterized. Compounds 1·X and 1·SCN·H₂O are constructed from binuclear planar Zn₂(atrz)₂ subunits and exhibit (4,4) topological network when the subunits are simplified as four-connected nodes. Based on changing the terminal counteranions X (X=Cl⁻, Br⁻, I⁻, SCN⁻), the average interlayer separations of 1·X and 1·SCN·H₂O are enlarged, which equal to 5.851, 6.153, 6.651 and 8.292 Å, respectively. As a result, H₂O molecules reside in the spaces between two adjacent layers of 1·SCN·H₂O. 2 and 1 are the isomorphous structures. In common with 1, the interlayer separations of 2·X are widened with increasing the ion radius. Solid-state luminescence properties and thermogravimetric analyses of 1 and 2 were investigated, respectively.     

Chloride anion-induced dimer capsule based on a polyfluorinated macrocycle meta-WreathArene

[1_n]metacyclophanes are a class of important building blocks for supramolecular assembly of artificial capsules. Herein we present the preparation and properties of a novel polyfluorinated macrocycle meta-WreathArene, a C₂-symmetrical [1₄]metacyclophane. Adopting a cone conformation in acetone solution, the macrocycle can form dimer capsules through hydrogen bonds induced by chloride anions. Each dimer capsule consists of two meta-WreathArene and two chloride anions, and has been unambiguously characterized both in solution and in solid state.     

羟丙基-β-环糊精磁性复合微粒的合成及作为阿霉素载体的体外释药研究

羟丙基-β-环糊精因具有内部疏水和外部亲水锥形圆筒空腔结构和良好的生物相容性在磁性药物载体方面有潜在应用价值。本研究将羟丙基-β-环糊精修饰在超顺磁性纳米四氧化三铁粒子表面制备磁性复合微粒,用红外光谱,透射电镜,振动磁强计,电感耦合等离子发射等方法对该复合微粒进行了表征,并将其用于抗肿瘤药物阿霉素的体外载药与释药实验研究。结果表明该复合微粒的粒径大小在10-20nm,饱和磁化强度59.9 emu/g,铁含量55.4%。对阿霉素的载药量为87.8 μg/mg。体外释药结果显示载药复合粒子在PBS中1天,4天,10天的累积释药量分别为35.5%, 49.3%, 76.5%,表明该载体具有一定的药物缓释功能。由此可知,羟丙基-β-环糊精磁性复合微粒可作为磁性靶向给药系统的有效载体。     

配合物[Cu2(bpe)X2] n (bpe =1, 2–trans–(4–pyridyl)ethene, X=Cl, Br, I )的合成、晶体结构及热稳定性研究

以1,2-反式-二（4-吡啶基）乙烯桥连卤化铜分别得到配合物[Cu₂(bpe)Cl ₂] _n (1), [Cu₂(bpe)Br₂] _n (2) 和 [Cu₂(bpe)I₂] _n (3)。通过X-射线单晶衍射法对配合物1的结构进行了研究,晶体学数据：单斜晶系, P 2(1)/c空间群, a = 0.3788(8) nm, b = 1.5059(3) nm, c = 1.0875(2)nm, β = 96.262(4) °, V = 616.5(2)ų, Z = 2, S = 1.002,最终残差因子( I >2 σ ( I )) R ₁ = 0.0288, wR ₂ = 0.0579,对于全部数据 R ₁ = 0.0509, wR ₂ = 0.0615。元素分析及红外光谱分析表明,该类配合物为同晶化合物。另外,通过热重分析对配合物的热稳定性进行了研究。     

4, 5-二氮芴-9-酮Cu(II)、Co(II)多核配合物的合成，晶体结构及DNA结合作用初探

合成了两个4, 5-二氮芴-9-酮Cu(II)、Co(II)的多核配合物[Cu2(CH3COO)4(H2O) 2]·2dafo 1 和 [(μ2-O)2-Co3(dafo)6] (ClO3)2·H2O 2 (dafo=4,5-diazafluoren-9-one) 并且对它们进行了元素分析,红外以及紫外光谱的表征,同时测定了配合物的晶体结构。用紫外光谱,发射光谱和循环伏安三种方法初步研究了配合物1和2与DNA的结合作用,结果表明,配合物1和2与DNA的结合为以插入作用为主 。     

氢氧化镧钠米线对多倍斯伏安响应的增敏作用及其应用

氢氧化镧钠米线修饰碳糊电极对多倍斯伏安响应有明显的增敏作用,其特征是多倍斯一对氧化还原峰的峰电流增大和峰电位差减小。这种增敏作用是由于氢氧化镧钠米线修饰电极有效面积的增大以及氢氧化镧钠米线与多倍斯间的化学作用。基于多倍斯在氢氧化镧钠米线修饰碳糊电极上灵敏的氧化峰,用线性扫描伏安法测定多倍斯,线性范围是3.0×10^-10～1.0×10^-8 mol·L^-1,检测限达5×10^-11mol·L^-1。     

1-氨基-1-肼基-2,2-二硝基乙烯(AHDNE)的合成、 晶体结构和理论计算

利用1,1-二氨基-2,2-二硝基乙烯(FOX-7)和水合肼在水体系中合成了1-氨基-1-肼基-2,2-二硝基乙烯(AHDNE), 并在甲醇溶液中培养出可用于X射线衍射的单晶. 晶体属正交晶系, 空间群为Pnma, 晶胞参数为: a＝0.6283(4) nm, b＝0.7713(5) nm, c＝1.2280(8) nm, a＝b＝g＝90°, V＝0.5950(7) nm3, Dc＝1.821 g/cm3, μ＝0.171 mm－1, F(000)＝336, Z＝4, R1＝0.0489, wR2＝0.1456. 选取标题化合物的一个结构单元作为初始模型, 运用Gaussian 03程序, 在6-311＋G(d)的基组水平上, 用HF, MP2以及B3LYP三种计算方法对标题化合物进行了几何全优化, 并对其成键情况及自然键轨道(NBO)进行了分析.     

Catalytic performance of imidazole modified HZSM-5 for methanol to aromatics reaction

A facile approach was developed for the preparation of nano-sized HZSM-5 with a hierarchical mesoporous structure by adding imidazole into conventional zeolite synthesis precursor solution. The physicochemical properties of modified HZSM-5 were characterized by X-ray diffraction(XRD), N_2 adsorption–desorption isotherms, scanning electron microscopy(SEM), NH_3-temperature-programmed desorption(NH_3-TPD) and pyridine adsorption infrared spectroscopy(Py-IR). The coke in spent catalysts was characterized by thermogravimetry(TG). The results showed that hierarchical HZSM-5 zeolites with excellent textural properties, such as abundant porous structure, uniform particle size and suitable acidity, could be synthesized by the recipe of one-pot synthesis routes. Moreover, the obtained HZSM-5 exhibited higher selectivity of total aromatics as well as longer lifetime in the catalytic conversion of methanol to aromatics, comparing with conventional HZSM-5. It is expected that the synthesis approach demonstrated here will be applicable to other zeolites with particular textural properties and controllable particle sizes, facilitating the emergence of new-type porous materials and their related applications in catalysis and separation.     

Visualizing tributyltin (TBT) in bacterial aggregates by specific rhodamine-based fluorescent probes

Here we present the first examples of fluorescent and colorimetric probes for microscopic TBT imaging. The fluorescent probes are highly selective and sensitive to TBT and have successfully been applied for imaging of TBT in bacterial Rhodobacter ferrooxidans sp. strain SW2 cell-EPS-mineral aggregates and in cell suspensions of the marine cyanobacterium Synechococcus PCC 7002 by using confocal laser scanning microscopy.     

A Cationic MOF with High Uptake and Selectivity for CO2 due to Multiple CO2‐Philic Sites

The reaction of N‐rich pyrazinyl triazolyl carboxyl ligand 3‐(4‐carboxylbenzene)‐5‐(2‐pyrazinyl)‐1H‐1,2,4‐triazole (H₂cbptz) with MnCl₂ afforded 3D cationic metal–organic framework (MOF) [Mn₂(Hcbptz)₂(Cl)(H₂O)]Cl ? DMF ? 0.5 CH₃CN ( 1 ), which has an unusual (3,4)‐connected 3,4T1 topology and 1D channels composed of cavities. MOF 1 has a very polar framework that contains exposed metal sites, uncoordinated N atoms, narrow channels, and Cl^? basic sites, which lead to not only high CO₂ uptake, but also remarkably selective adsorption of CO₂ over N₂ and CH₄ at 298–333 K. The multiple CO₂‐philic sites were identified by grand canonical Monte Carlo simulations. Moreover, 1 shows excellent stability in natural air environment. These advantages make 1 a very promising candidate in post‐combustion CO₂ capture, natural‐gas upgrading, and landfill gas‐purification processes.