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The current study describes the synthesis, electrochemical, computational, and photochemical properties of octa (3-hydroxypropylthio) substituted cobalt (II) ( 4 ), copper (II) ( 5 ), nickel (II) ( 6 ) and zinc(II) ( 7 ) phthalocyanine derivatives. These novel compounds were characterized by elemental analysis,1H,13C NMR, FT-IR, UV-Vis, and MS. The redox behaviors of these metallo-phthalocyanines were investigated by the cyclic voltammetric method. The optimized molecular structure and gauge-including atomic orbital (GIAO)1H and13C NMR chemical shift values of these phthalocyanines in the ground state had been calculated by using B3LYP/6–31G(d,p) basis set. The outcomes of the optimized molecular structure were given and compared with the experimental NMR values. The photochemical properties including photodegradation and singlet oxygen generation of zinc(II) phthalocyanine were studied in DMSO solution for the determination of its photosensitizer behaviors.  相似文献   
2.
Closed trajectories and global controllability in the plane   总被引:3,自引:0,他引:3  
In the plane, results are given about the structure of closedtrajectories which may occur as simple closed curves or generalclosed curves with self-intersections. Necessary conditionsfor the global controllability of nonlinear systems that arein the so-called linear-analytic form = f(x)+ug(x), where x R2 and u 1, are given. It is provedthat, if there exists a closed trajectory of the system, then either contains a point where f and g are linearly dependent,or encloses some zeros of f + ug for all u [-1,1]. Then thisresult is used to prove that, if the linear-analytic systemis controllable and the vector field g is never zero in W R2,then W contains some zeros of f + ug for some u [-1,1]. A topologicalapproach is taken. Remarks are made about the size of the regionwhere a closed trajectory can lie, and about the shape of theclosed trajectories. Further implications are discussed.  相似文献   
3.
Cancer is a disease characterized by the continuous growth of cells without adherence to the rules that healthy normal cells obey. Carbonic anhydrase I and II (CA I and CA II) inhibitors are used for the treatment of some diseases. The available drugs in the market have limitations or side effects, which bring about the need to develop new drug candidate compound(s) to overcome the problems at issue. In this study, new pyrazole-sulphonamide hybrid compounds 4-[5-(1,3-benzodioxol-5-yl)-3-aryl-4,5-dihydro-1 H -pyrazol-1-yl]benzenesulphonamides (4a - 4j) were designed to discover new drug candidate compounds. The compounds 4a - 4j were synthesized and their chemical structures were confirmed using spectral techniques. The hypothesis tested was whether an introduction of methoxy and polymethoxy group(s) lead to an increased potency selectivity expression (PSE) value of the compound, which reflects cytotoxicity and selectivity of the compounds. The cytotoxicity of the compounds towards tumor cell lines were in the range of 6.7 – 400 µM. The compounds 4i (PSE2 = 461.5) and 4g (PSE1 = 193.2) had the highest PSE values in cytotoxicity assays. Ki values of the compounds were in the range of 59.8 ± 3.0 - 12.7 ± 1.7 nM towards hCA I and in the range of 24.1 ± 7.1 - 6.9 ± 1.5 nM towards hCA II. While the compounds 4b, 4f, 4g, and 4i showed promising cytotoxic effects, the compounds 4c and 4g had the inhibitory potency towards hCA I and hCA II, respectively. These compounds can be considered as lead compounds for further research.  相似文献   
4.
Using linear approximations of nonlinear systems has long beena practice to design control laws. In this paper, an analysisis given involving linear approximation of the nonlinear controlsystem and small-time reachable sets in R2. A useful concept,the swing–out, which is a measure of nonlinearity, isdefined. This is used to examine the relationship between thesmall-time reachable sets of the nonlinear control system andits linear approximation. Behaviour of the nonlinear systemunder a control law is examined within this context. More factsare given about the swing-out for some special cases.  相似文献   
5.
In this work,some thermodynamic properties of poly(cyclohexyl methacrylate)were studied by inverse gas chromatography(IGC).For this purpose,the polymeric substance was coated on Chromosorb W and which was filled into a glass column.The retention times(tr)of the probes were determined from the interactions of poly(cyclohexyl methacrylate)with n-pentane,n-hexane,n-heptane,n-octane,n-decane,methanol,ethanol,2-propanol,butanol,acetone,ethyl methyl ketone,benzene,toluene and o-xylene by IGC technique.Then,the specific volume(V0g)was determined for each probe molecule.By using(1/T;ln V0g)graphics,the glass transition temperature of poly(cyclohexyl methacrylate)was found to be 373 K.The adsorption heat under the glass transition temperature(ΔHa),and partial molar heat of sorption above the glass transition(ΔHS1),partial molar free energy of sorption(ΔGS1)and partial molar entropy of sorption(ΔSS1)belonging to sorption for every probe were calculated.The partial molar heat of mixing at infinite dilution(ΔH∞1),partial molar free energy of mixing at infinite dilution(ΔG∞1),Flory-Huggins interaction parameter(χ∞12)and weight fraction activity coefficient(a1/w1)∞values of polymer-solute systems were calculated at different column temperatures.The solubility parameters(δ2)of the polymer were obtained by IGC technique.  相似文献   
6.
The newly synthesized cyclotriphosphazene cored coumarin chemosensors 5, 6, and 7 were successfully characterized by 1 H NMR, 31 P NMR, and MALDI-TOF mass spectrometry. Additionally, the photophysical and metal sensing properties of the targeted compounds were determined by fluorescence spectroscopy in the presence of various metals (Li + , Na + , K + , Cs + , Mg 2+ , Ca 2+ , Ba 2+ , Cr 3+ , Mn 2+ , Fe 3+ , Co 2+ , Al 3+ , Hg + , Cu 2+ , Zn 2+ , Ag + , and Cd 2+ ) . The fluorescence titration results showed that compounds 5, 6, and 7 could be employed as fluorescent chemosensors for Fe 3+ ions with high sensitivity. The complex stoichiometry between final cyclotriphosphazene chemosensors and Fe 3+ ions was also determined by Job’s plots.  相似文献   
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