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991.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献
992.
Di Sun Geng-Geng Luo Na Zhang Jian-Hua Chen Rong-Bin Huang Li-Rong Lin Lan-Sun Zheng 《Polyhedron》2009,28(14):2983-2988
Using the principle of crystal engineering, three new silver metal–organic coordination polymers, [Ag2(L1)2(L2)]·2H2O (1), [Ag2(L1)2(L3)]·H2O (2), [Ag2(L1)2(L4)]·2H2O (3) (L1 = 2-aminopyrimidine, L2 = oxalate anion, L3 = glutarate anion and L4 = 1,4-naphthalenedicarboxylate anion) have been synthesized by solution phase reactions of silver nitrate with various dicarboxylic acids and cooperative heterocyclic 2-aminopyrimidine ligand under the ammoniacal conditions. All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. In complex 1, L1 ligands are coordinated to Ag(I) metal centers in rare tridentate fashions, forming one-dimensional (1-D) ladder-like structure, which is interlinked by L2 anions to generate 2-D pleated molecular sheet. Complex 2 displays an interesting two-dimensional (2-D) tongue-and-groove structure containing a new kind of “T-shaped” unit. Meanwhile, each of 2-D bilayers is interlocked by four adjacent identical motifs to form three-dimensional (3-D) 5-fold interpenetrating conformation with weak Ag···Ag interactions. In complex 3, L1 ligands are coordinated to the Ag(I) ions to form 1-D polymeric chain. And L4 anions, acting as bridging linkers through corresponding μ2-carboxylates, link a pair of Ag(I) atoms from adjacent chains to yield 3-D supramolecular network. The structures of complexes 1–3 which span from 2-D to 3-D networks suggest that dicarboxylate anions play important role in the formation of such coordination architectures. 相似文献
993.
Zhong Jun bo Ma Di He Xi yang Li Jian zhang Chen Yao qiang 《Journal of Sol-Gel Science and Technology》2009,52(1):140-145
It has been found that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene can be greatly enhanced by loading TiO2 on the surface of SrAl2O4: Eu2+, Dy3+ using sol–gel technology. The prepared photocatalyst was characterized by BET, XRD, and XPS analyses. XRD results reveal
that the peaks of titania in either rutile or anatase form are not detected by XRD in the 2θ region from 20° to 50°. The binding
energy values of Ti 2p of pure TiO2 are 458.90 and 464.60 eV, while for TiO2/SrAl2O4: Eu2+, Dy3+, the binding energy values of Ti 2p are 458.50 and 464.20 eV. The results indicate that the optimum loading of TiO2 is 1 wt% and TiO2/SrAl2O4: Eu2+, Dy3+ (1 wt%) demonstrates 1.4 times the photocatalytic activity of that of pure TiO2, but the underlying mechanism of SrAl2O4: Eu2+, Dy3+ in the photocatalytic reaction remains to be unraveled. 相似文献
994.
Use was made of thermal and other techniques to characterise three native asphalt samples. The purpose was to support archaeological
investigations reconstructing their thermal history and composition. The first sample (from a Roman quarry in central Italy)
proved to have 37% impurities, no sign of oxidation or degradation and to have never been heated to above 100°C. The second
sample (from a Roman ship sunk south of France) was pure, but partially oxidised, with a saturated fraction in its structure.
Analyses of the latter sample, obtained from the eye of a Thracian bronze head, revealed that the asphalt had been heated
to over 100°C and then mixed with natural wax. 相似文献
995.
Maria Lasaosa Nathanaël Delmotte Christian G. Huber Katja Melchior Elmar Heinzle Andreas Tholey 《Analytical and bioanalytical chemistry》2009,393(4):1245-1256
The separation of complex peptide mixtures in shotgun proteome analysis using a 2D separation scheme encompassing reversed-phase
× ion-pair reversed-phase (IP-RP) liquid chromatography coupled online to electrospray ion trap mass spectrometry (MS) has
been shown earlier to be superior in terms of separation efficiency and technical robustness compared to the classically used
separation scheme encompassing strong cation exchange × IP-RP-chromatography in shotgun proteome analysis. In the present
study, this novel separation scheme was coupled offline to matrix-assisted laser desorption/ionization (MALDI) time-of-flight
(TOF)/TOF-MS for the analysis of the same sample, a tryptic digest of the cytosolic proteome of the bacterium Corynebacterium glutamicum. Compared to the earlier study, the MALDI-based platform led to a significantly increased number of peptides (7,416 vs. 2,709)
and proteins (1,208 vs. 468, without single peptide-based identifications), respectively. This represents the majority of
all predicted cytosolic proteins in C. glutamicum. The high proteome coverage, as well as the large number of low-abundant proteins identified with this improved analytical
platform, pave the way for new biological studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
996.
We report measurements of the speed of sound in mixtures of N-methyl-2-pyrrolidinone and methanol at temperatures between 298.15 K and 343.15 K and at pressures up to 60 MPa. The measurements were made using a dual path pulse-echo apparatus operating at a frequency of 5 MHz. We have also measured the isobaric specific heat capacity of each mixture as a function of temperature at ambient pressure, by means of a Setaram DSC III microcalorimeter. The experimental results have been combined with literature data for the density of the same mixtures as a functions of temperature at ambient pressure to obtain the density, isobaric specific heat capacity, and other thermodynamic properties at temperatures between 298.15 K and 343.15 K and at pressures up to 60 MPa. Detailed comparisons with the literature data are presented. 相似文献
997.
Maria G. Babashkina Damir A. Safin Dr. Łukasz Szyrwiel Maria Kubiak Felix D. Sokolov Yuri V. Starikov Henryk Kozlowski 《无机化学与普通化学杂志》2009,635(3):554-557
Reaction of the potassium salt of N‐thiophosphorylated thiourea α‐naphthylNHC(S)NHP(S)(OiPr)2 ( HL ) with Cu(PPh3)3I in aqueous EtOH/CH2Cl2 leads to the mononuclear complex [Cu(PPh3)2L–S,S′]. By using copper(I) iodide instead ofCu(PPh3)3I, the polynuclear complex [Cun(L–S,S′)n] was obtained. The structures of these compounds were investigated by elemental analysis, 1H and 31P{1H} NMR and IR spectroscopy. The crystal structures of HL and Cu(PPh3)2L were determined by single‐crystal X‐ray diffraction. 相似文献
998.
Barbara Di Credico Dipl.‐Chem. Fabrizia Fabrizi de Biani Dr. Luca Gonsalvi Dr. Annalisa Guerri Dr. Andrea Ienco Dr. Franco Laschi Prof. Dr. Maurizio Peruzzini Dr. Gianna Reginato Dr. Andrea Rossin Dr. Piero Zanello Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(44):11985-11998
The reaction of [CpRuCl(PPh3)2] (Cp=cyclopentadienyl) and [CpRuCl(dppe)] (dppe=Ph2PCH2CH2PPh2) with bis‐ and tris‐phosphine ligands 1,4‐(Ph2PC≡C)2C6H4 ( 1 ) and 1,3,5‐(Ph2PC≡C)3C6H3 ( 2 ), prepared by Ni‐catalysed cross‐coupling reactions between terminal alkynes and diphenylchlorophosphine, has been investigated. Using metal‐directed self‐assembly methodologies, two linear bimetallic complexes, [{CpRuCl(PPh3)}2(μ‐dppab)] ( 3 ) and [{CpRu(dppe)}2(μ‐dppab)](PF6)2 ( 4 ), and the mononuclear complex [CpRuCl(PPh3)(η1‐dppab)] ( 6 ), which contains a “dangling arm” ligand, were prepared (dppab=1,4‐bis[(diphenylphosphino)ethynyl]benzene). Moreover, by using the triphosphine 1,3,5‐tris[(diphenylphosphino)ethynyl]benzene (tppab), the trimetallic [{CpRuCl(PPh3)}3(μ3‐tppab)] ( 5 ) species was synthesised, which is the first example of a chiral‐at‐ruthenium complex containing three different stereogenic centres. Besides these open‐chain complexes, the neutral cyclic species [{CpRuCl(μ‐dppab)}2] ( 7 ) was also obtained under different experimental conditions. The coordination chemistry of such systems towards supramolecular assemblies was tested by reaction of the bimetallic precursor 3 with additional equivalents of ligand 2 . Two rigid macrocycles based on cis coordination of dppab to [CpRu(PPh3)] were obtained, that is, the dinuclear complex [{CpRu(PPh3)(μ‐dppab)}2](PF6)2 ( 8 ) and the tetranuclear square [{CpRu(PPh3)(μ‐dppab)}4](PF6)4 ( 9 ). The solid‐state structures of 7 and 8 have been determined by X‐ray diffraction analysis and show a different arrangement of the two parallel dppab ligands. All compounds were characterised by various methods including ESIMS, electrochemistry and by X‐band ESR spectroscopy in the case of the electrogenerated paramagnetic species. 相似文献
999.
The development of efficient and sensitive analytical methods for the separation, identification and quantification of complex biological samples is continuously a topic of high interest in biological science. In the present study, the possibility of using a polyether ether ketone (PEEK) capillary for the CE separation of peptides, proteins and other biological samples was examined. The performance of the tubing was compared with that of traditional silica capillaries. The CE analysis was performed using contactless conductivity detection (C4D), which eliminated any need for the detection window and was suitable for the detection of optically inactive compounds. In the PEEK capillary the cathodic EOF was low and of excellent stability even at extremes pH. In view of this fast biological anions were analyzed using an opposite end injection technique without compromising separation. A comparison of the performances of fused‐silica and polymer capillaries during the separation of model sample mixtures demonstrated the efficiency and separation resolution of the latter to be higher and the reproducibility of the migration times and peak areas is better. Furthermore, PEEK capillaries allowed using simple experimental conditions without any complicated modification of the capillary surface or use of an intricate buffer composition. The PEEK capillaries are considered as an attractive alternative to the traditional fused‐silica capillaries and may be used for the analysis of complex biological mixtures as well as for developing portable devices. 相似文献
1000.