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61.
[Zn2(PCP)(phen)(H2O)F]n 1 and {[Zn3(MCP)2(phen)2(H2O)]·2.5H2O}n 2(PCP = p-O2C(C6H4)PO33-,MCP = m-O2C(C6H4)PO33- and phen = phenanthroline) were obtained by hydrothermal synthesis and characterized by X-ray single-crystal diffraction.Compound 1 crystallizes in the monoclinic P21/c space group with a = 7.908(2),b = 20.254(3),c = 13.477(2) ,β = 107.76(3)°,V = 2055.7(8) 3,Z = 4,C20H16FN2O6PZn2,Mr = 561.10,Dc = 1.813 g/cm3,μ = 2.463 mm-1,F(000) = 1128,the final R = 0.0340 and wR = 0.0794.Compound 2 crystallizes in the monoclinic P21/n space group with a = 15.629(3),b = 18.141(4),c = 17.723(7) ,β = 121.89(2)°,V = 4267(2) 3,Z = 4,C40H31N4O13.5P2Zn3,Mr = 1041.70,Dc = 1.620 g/cm3,μ = 1.818 mm-1,F(000) = 2108,the final R = 0.0669 and wR = 0.1775.In compound 1,the tetranuclear Zn4 units are linked together by μ4-PCP3- to build 2D(4,4) layers,which are further interconnected through the μ2-bridging fluorion into a 3D framework with 1D phen ligands-filled channels.As for the 3D supramolecular framework of 2,the novel hexanuclear Zn6 units with "chair" conformation are extended by the moieties of μ4-MCP3- ligand to a 2D(4,4) layer on the bc plane,which is viewed as the 2-folded layers in 1.In both compounds,the structures are stabilized by hydrogen bonding interactions and π-π stacking interactions between the phen rings.Additionally,FT-IR spectroscopy and the fluorescent properties are discussed. 相似文献
62.
Razieh FAZAELI Hamid ALIYAN Shadpour MALLAKPOUR Zahra RAFIEE Maryam BORDBAR 《催化学报》2011,32(4):582-588
A novel compound constructed from polyoxometalate (H3PW12O40,PW12) and poly(amidoamine) (PA) was prepared at room temperature in an aqueous solution by an impregnation method.A series of novel 1,3,5-triaryl-2-pyrazoline derivatives was synthesized by the reaction between chalcone and phenylhydrazine in the presence of the title compound,PW12/PA,in high yields.The structures of the compounds obtained were determined by IR and 1H NMR spectra. 相似文献
63.
Pérez-Ojeda ME Trastoy B López-Arbeloa Í Bañuelos J Costela Á García-Moreno I Chiara JL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(47):13258-13268
New hybrid organic–inorganic dyes based on an azide‐functionalized cubic octasilsesquioxane (POSS) as the inorganic part and a 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BDP) chromophore as the organic component have been synthesized by copper(I)‐catalyzed 1,3‐dipolar cycloaddition of azides to alkynes. We have studied the effects of the linkage group of BDP to the POSS unit and the degree of functionalization of this inorganic core on the ensuing optical properties by comparison with model dyes. The high fluorescence of the BDP dye is preserved in spite of the linked chain at its meso position, even after attaching one BDP moiety to the POSS core. The laser action of the new dyes has been analyzed under transversal pumping at 532 nm in both the liquid phase and when incorporated into solid polymeric matrices. The monosubstituted new hybrid dye exhibits high lasing efficiency of up to 56 % with high photostability, with its laser output remaining at the initial value after 4×105 pump pulses in the same position of the sample at a repetition rate of 30 Hz. However, functionalization of the POSS core with eight fluorophores leads to dye aggregation, as quantum mechanical simulation has revealed, worsening the optical properties and extinguishing the laser action. The new hybrid systems based on dye‐linked POSS nanoparticles open up the possibility of using these new photonic materials as alternative sources for optoelectronic devices, competing with dendronized or grafted polymers. 相似文献
64.
Deng S Fulghum TM Krueger G Patton D Park JY Advincula RC 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(32):8929-8940
A series of hybrid Au-nanoparticle-dendrimer materials: nanoparticle-cored thiophene dendrimers (NCTDs) were synthesized, characterized, and investigated for their energy-transfer properties. These hybrid nanoparticles were obtained by the simultaneous and in situ reduction of gold(III) chloride and self-assembly of the thiol-containing thiophene dendritic ligands. The dendron ligands were radially attached to the gold nanoparticles and were analyzed by TEM, UV/Vis, (1)H NMR, and FTIR spectroscopies. The solution fluorescence of the attached thiophene dendrons are quenched progressively. Both alkyl-chain length and dendron size have significant influence on the energy-transfer efficiency, as well as on core sizes and size distribution of the Au nanoparticles. In spite of the phenomenon's dependence on nanoparticle size, the energy transfer generally follows the 1/d(2) distance dependence. Single NCTD nanoparticles were also adsorbed on highly ordered pyrolytic graphite (HOPG) and uniform aggregates were observed on mica flat substrates. 相似文献
65.
Yu‐Fei Song De‐Liang Long Chris Ritchie Leroy Cronin 《Chemical record (New York, N.Y.)》2011,11(3):158-171
The latest advances in the area of polyoxometalate (POM)‐based inorganic/organic hybrid materials prepared by self‐assembly, covalent modification, and supramolecular interactions are presented. This Review is composed of five sections and documents the effect of organic cations on the formation of novel POMs, surfactant encapsulated POM‐based hybrids, polymeric POM/organic hybrid materials, POMs‐containing ionic crystals, and covalently functionalized POMs. In addition to their role in the charge‐balancing, of anionic POMs, the crucial role of organic cations in the formation and functionalization of POM‐based hybrid materials is discussed. DOI 10.1002/tcr.201100002 相似文献
66.
67.
DNA‐Hybrid‐Gated Multifunctional Mesoporous Silica Nanocarriers for Dual‐Targeted and MicroRNA‐Responsive Controlled Drug Delivery 下载免费PDF全文
Penghui Zhang Fangfang Cheng Ri Zhou Dr. Juntao Cao Dr. Jingjing Li Prof. Dr. Clemens Burda Dr. Qianhao Min Prof. Dr. Jun‐Jie Zhu 《Angewandte Chemie (International ed. in English)》2014,53(9):2371-2375
The design of an ideal drug delivery system with targeted recognition and zero premature release, especially controlled and specific release that is triggered by an exclusive endogenous stimulus, is a great challenge. A traceable and aptamer‐targeted drug nanocarrier has now been developed; the nanocarrier was obtained by capping mesoporous silica‐coated quantum dots with a programmable DNA hybrid, and the drug release was controlled by microRNA. Once the nanocarriers had been delivered into HeLa cells by aptamer‐mediated recognition and endocytosis, the overexpressed endogenous miR‐21 served as an exclusive key to unlock the nanocarriers by competitive hybridization with the DNA hybrid, which led to a sustained lethality of the HeLa cells. If microRNA that is exclusively expressed in specific pathological cell was screened, a combination of chemotherapy and gene therapy should pave the way for a targeted and personalized treatment of human diseases. 相似文献
68.
Multivalent Recognition of Concanavalin A by {Mo132} Glyconanocapsules—Toward Biomimetic Hybrid Multilayers 下载免费PDF全文
Dr. Mihail Barboiu Dr. Zineb Mouline Dr. Mihaela Silion Erol Licsandru Prof. Bogdan C. Simionescu Dr. Eugene Mahon Dr. Mariana Pinteala 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6678-6683
Herein, we consider Müller’s spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42‐ [{(MoVI)MoVI5O21(H2O)6}12{MoV2O4(CH3COO)}30]?10 CH3COONH4? 300 H2O≡(NH4)42? 1 a ?crystal ingredients≡ 1 , {Mo132}, as an effective sugar‐decorated nanoplatform for multivalent lectin recognition. The ion‐exchange of NH4+ ions of 1 with cationic‐sugars, D ‐mannose‐ammonium chloride ( 2 ) or D ‐glucose‐ammonium chloride ( 3 ) results in the formation of glyconanocapsules (NH4)42?n 2 n? 1 a and (NH4)42?m 3 m? 1 a . The Mannose (NH4)42?n 2 n? 1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of ${K{{{\rm multi}\hfill \atop {\rm a}\hfill}}}$ =4.6×104 M ?1 and an enhancement factor of β=K${{{{\rm multi}\hfill \atop {\rm a}\hfill}}}$ /K${{{{\rm mono}\hfill \atop {\rm ass}\hfill}}}$ =21.9, reminiscent of the formation of “glycoside clusters” on the external surface of glyconanocapsule. The glyconanocapsules (NH4)42?n 2 n? 1 a and (NH4)42?m 3 m? 1 a self‐assemble in “hybrid multilayers” by successive layer‐by‐layer deposition of (NH4)42?n 2 n? 1 a or (NH4)42?m 3 m? 1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The “biomimetic hybrid multilayers” described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage‐delivery devices. 相似文献
69.
Molecularly Designed Nanoparticles by Dispersion of Self‐Assembled Organosiloxane‐Based Mesophases 下载免费PDF全文
Shigeru Sakamoto Yasuhiro Tamura Dr. Hideo Hata Dr. Yasuhiro Sakamoto Prof. Atsushi Shimojima Prof. Kazuyuki Kuroda 《Angewandte Chemie (International ed. in English)》2014,53(35):9173-9177
The design of siloxane‐based nanoparticles is important for many applications. Here we show a novel approach to form core–shell silica nanoparticles of a few nanometers in size through the principle of “dispersion of ordered mesostructures into single nanocomponents”. Self‐assembled siloxane–organic hybrids derived from amphiphilic alkyl‐oligosiloxanes were postsynthetically dispersed in organic solvent to yield uniform nanoparticles consisting of dense lipophilic shells and hydrophilic siloxane cores. In situ encapsulation of fluorescent dyes into the nanoparticles demonstrated their ability to function as nanocarriers. 相似文献
70.