Metal complexes ([ML2], where M = Fe, Co, or Zn; HL = 2-[(6-ethyl-5-oxo-4,5-dihydro-2H-[1,2,4]triazin-3-ylidene)-hydrazono]-butyric acid, C9H13N5O3) of a Schiff base derived from α-ketobutyric acid (α-KBA) and diaminoguanidine (Damgu) were synthesized and characterized using elemental, spectral, and thermal studies. The metal complexes exhibited similar decomposition behavior, with a highly exothermic final decomposition step resulting in the formation of metal oxides. Isomorphism among the complexes was revealed using a powder X-ray diffraction (PXRD) technique. Solid solution precursors ([Zn1/3M2/3(L)2], where M = Fe, Co) were synthesized and characterized using various physico-chemical techniques. A thermal decomposition technique was used to prepare spinel-type zinc cobaltite (ZnCo2O4) and zinc ferrite (ZnFe2O4) nanocrystalline particles with the synthesized single source precursors. Structural studies using PXRD ascertained the predominant crystal phase to be spinel. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) showed a mean nanoparticle size of 18 ± 2 nm. Magnetic measurements revealed a weak magnetic behavior in the synthesized spinels. In the aqueous phase, the spinels exhibited catalytic activity, reducing 4-nitrophenol (4-NP) in the presence of NaBH4 at room temperature. Additionally, the study demonstrated that the catalyst can be recovered and reused for five cycles with a more than 85% conversion efficiency. 相似文献
Research on Chemical Intermediates - The present research work explores an environmental benign, lucrative approach for the synthesis of cauliflower-like Ag/MgO nanocomposite using Musa paradisiaca... 相似文献
Hybrid materials possessing piezo- and ferroelectric properties emerge as excellent alternatives to conventional piezoceramics due to their merits of facile synthesis, lightweight nature, ease of fabrication and mechanical flexibility. Inspired by the structural stability of aminophosphonium compounds, here we report the first A3BX6 type cyanometallate [Ph2(iPrNH)2P]3[Fe(CN)6] ( 1 ), which shows a ferroelectric saturation polarization (Ps) of 3.71 μC cm−2. Compound 1 exhibits a high electrostrictive coefficient (Q33) of 0.73 m4 C−2, far exceeding those of piezoceramics (0.034–0.096 m4 C−2). Piezoresponse force microscopy (PFM) analysis demonstrates the polarization switching and domain structure of 1 further confirming its ferroelectric nature. Furthermore, thermoplastic polyurethane (TPU) polymer composite films of 1 were prepared and employed as piezoelectric nanogenerators. Notably, the 15 wt % 1 -TPU device gave a maximum output voltage of 13.57 V and a power density of 6.03 μW cm−2. 相似文献
The helium energy spectrum in Martian orbit has been observed by the MARIE charged particle spectrometer aboard the 2001 Mars Odyssey spacecraft. The orbital data were taken from March 13, 2002 to October 28, 2003, at which time a very intense Solar Particle Event caused a loss of communication between the instrument and the spacecraft. The silicon detector stack in MARIE is optimized for the detection of protons and helium in the energy range below , which typically includes almost all of the flux during SPEs. This also makes MARIE an efficient detector for GCR helium in the energy range of 50–. We will present the first fully normalized flux results from MARIE, using helium ions in this energy range. 相似文献
The control of surface wettability of indium tin oxide (In2O3-SnO2) coated glass surfaces is studied. We report here the first observation of purely electrochemical generation of super-hydrophilic surfaces at In2O3-SnO2 electrodes in the absence of an ultraviolet illumination source. This is achieved by the application of high anodic potentials for a prolonged period. Such surfaces are reversibly converted back to their original hydrophobic state on storage in air (one or two days) or water (a week)(and vice versa). The unique character of these surfaces can be attributed to the surface structure of the hydrophilic phase. 相似文献
An extended technicolour grand unification model based on the gauge groupE6×SU(7) extended technicolour is presented. The symmetry-breaking based on extended technicolour theory is discussed. It is
shown that the existing phenomenology is well explained by the model. The strangeness changing neutral currents may not be
a problem with this model. 相似文献
New divalent transition metal 3,5-pyrazoledicarboxylate
hydrates of empirical formula Mpz(COO)2(H2O)2,
where M=Mn, Co, Ni, Cu, Zn and Cd (pz(COO)2=3,5-pyrazoledicarboxylate),
metal hydrazine complexes of the type Mpz(COO)2N2H4
where M=Co, Zn or Cd and Mpz(COO)2nN2H4·H2O,
where n=1 for M=Ni
and n=0.5 for M=Cu
have been prepared and characterized by physico-chemical methods. Electronic
spectroscopic data suggest that Co and Ni complexes adopt an octahedral geometry.
The IR spectra confirm the presence of unidentate carboxylate anion (Δν=νasy(COO–)–νsym(COO–)>215
cm–1) in all the complexes and bidentate
bridging hydrazine (νN–N=985–950 cm–1)
in the metal hydrazine complexes. Both metal carboxylate and metal hydrazine
carboxylate complexes undergo endothermic dehydration and/or dehydrazination
followed by exothermic decomposition of organic moiety to give the respective
metal oxides as the end products except manganese pyrazoledicarboxylate hydrate,
which leaves manganese carbonate. X-ray powder diffraction patterns reveal
that the metal carboxylate hydrates are isomorphous as are those of metal
hydrazine complexes of cobalt, zinc and cadmium. 相似文献
The present investigation has been carried out to optimize the pH level of lanthanum (La)-doped tin dioxide (SnO2) nanoparticles towards the potential application in gas sensor. The La-doped SnO2 nanoparticles were synthesized by sol-gel method in different pH values varying from acidic to base nature. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), ultraviolet (UV), photoluminescence (PL), and scanning electron microscopy (SEM) techniques. The XRD, UV, and PL analyses show the pH influences on the crystallite size of La-doped SnO2 nanoparticles. The SEM images show the formation of porous structure at pH 11. Also, the electrical conductivity of 1 mol% La-doped SnO2 at pH 3 and pH 11 were measured by impedance analyzer. In addition, we have fabricated and demonstrated device performance of synthesized La-doped SnO2 nanoparticles for gas-sensing application. Real-time current response and long-time response to the gas sensing were also studied for the fabricated device.
Cation interactions with π-systems are a problem of outstanding contemporary interest and the nature of these interactions seems to be quite different for transition and main group metal ions. In this paper, we have systematically analyzed the contrast in the bonding of Cu(+) and main group metal ions. The molecular structures and energetics of the complexes formed by various alkenes (A = C(n)H(2n), n = 2-6; C(n)H(2n- 2), n = 3-8 and C(n)H(2n + 2), n = 5-10) and metal ions (M = Li(+), Na(+), K(+), Ca(2+), Mg(2+), Cu(+) and Zn(2+)) are investigated by employing ab initio post Hartree-Fock (MP2/6-311++G**) calculations and are reported in the current study. The study, which also aims to evaluate the effect of the size of the alkyl portion attached to the π-system on the complexation energy, indicates a linear relationship between the two. The decreasing order of complexation energy with various metal ion-alkene complexes follows the order Zn(2+)-A > Mg(2+)-A > Ca(2+)-A > Cu(+)-A > Li(+)-A > Na(+)-A > K(+)-A. The increased charge transfer and the electron density at (3,-1) intermolecular bond critical point corroborates well with the size of the π-system and the complexation energy. The observed deviation from the linear dependency of the Cu(+)-A complexes is attributed to the dπ→π* back bonding interaction. An energy decomposition analysis via the reduced variational space (RVS) procedure was also carried out to analyze which component among polarization, charge transfer, coulomb and exchange repulsion contributes to the increase in the complexation energy. The RVS results suggest that the polarization component significantly contributes to the increase in the complexation energy when the alkene size increases. 相似文献