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1.
A novel kind of organic–inorganic monomer SUASi has been achieved by modifying 5-sulfosalicylic acid (SUA) with 3-aminopropyltrimethoxysilane
(APS), subsequently binary and ternary Eu3+ mesoporous hybrid materials with 5-sulfosalicylic acid (SUA)-functionalized SBA-15 and 1,10-phenanthroline (phen) are synthesized
by co-condensation of SUASi and TEOS in the presence of Eu3+ complex and Pluronic P123 as a template. Finally, luminescent hybrid mesoporous materials consisting of active rare earth
ions (Eu3+)—inert rare earth ions (Y3+, La3+, Gd3+) complex covalently bonded to the mesoporous materials network have been obtained via this sol–gel approach. The physical
characterization and photoluminescence of all these resulting materials are studied in detail. Especially the luminescent
behavior has been studied with the different ratios of Eu3+–(Y3+, La3+, Gd3+), which suggests that the existence of inert rare earth ions can enhance the luminescence intensity of Eu3+. This may be due to the intramolecular energy transfer between Y3+, La3+, Gd3+, and Eu3+ through the covalently bonded mesoporous framework. 相似文献
2.
A. O. Chauhan A. B. Gawande S. K. Omanwar 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(5):1023-1027
The phosphors LiSrPO4:Gd3+ and LiSrPO4:Gd3+, Pb2+ with different concentration of Gd3+ and Pb2+ were synthesized by combination of re-crystallization and modified solid state diffusion method. The synthesized phosphors were characterized using XRD, SEM and PL spectroscopies. The PL excitation spectra of LiSrPO4:Gd3+ phosphor exhibit peak at 275 nm due to the 8S7/2 →4IJ transition of Gd3+ ions and gave narrow UVB emission at 312 nm. The effect of Pb2+ ions on the PL properties of LiSrPO4:Gd3+have also been investigated. Upon the addition of Pb2+ ions, the excitation of phosphors shows broad peak with maximum at 247 nm, overlapping the Hg 253.7 nm line. This addition of Pb2+ ions improved the emission intensity of narrow band UVB i.e. 312 nm under the excitation of 247 nm. The phosphor could be good candidate as phototherapy lamp phosphor material. 相似文献
3.
K. Rajasekhar Babu M. Purnachandra Rao P. S. V. Subba Rao K. Rama Rao B. Kishore Babu B. Rajesh Babu 《Journal of Inorganic and Organometallic Polymers and Materials》2017,27(3):612-621
In this work, the effect of Cu content on structural and magnetic properties of Cobalt–Zinc Ferrite nanoparticles synthesized by sol–gel combustion method have been investigated. All the samples exhibit cubic spinel structure and the lattice constant decreases linearly with increasing Cu-content. Average crystallite sizes calculated from Debye–Scherrer formula are in the range of 51–100 nm. The broadening of X-ray diffraction peaks decrease with increasing Cu content ‘x’ suggest that crystallite size increases with increasing ‘x’. Cation distribution estimated form X-ray line intensity calculations show that Cu ions simultaneously occupy tetrahedral (A) and octahedral (B) sites with different ratio and Zn and Co ions occupies A and B sites respectively. With increasing Cu content a fraction of Co ions migrate to A site when x?>0.2. Grain sizes estimated from SEM are found to be increase with increasing Cu content. Particle size calculated using TEM for the undoped Co–Zn ferrites is about 55 nm. Saturation magnetization (Ms), Coercivity (Hc) and remanent magnetization (Mr) that varies significantly with Cu-Content. Saturation magnetization decreases from 90.7 emu/g (x?=?0.0) to 51 emu/g (x?=?0.4). The proposed cation distribution supports the variation in saturation magnetization and Coercivity with increasing Cu content. 相似文献
4.
S. S. Ordan’yan S. V. Vikhman Yu. S. Nagaeva 《Refractories and Industrial Ceramics》2009,50(2):127-130
Sections are constructed for WSi2–Me
VB2 of the quaternary systems W–Si–(V, Nb, Ta)–B described by eutectic diagrams of state with T
eut (1940 ± 20), (1980 ± 20) and (2020 ± 30)°C and a boride content in the eutectics of 35, 20 and 15 mol.% respectively.
Translated from Novye Ogneupory, No. 3, pp. 41 – 44, March 2009. 相似文献
5.
M. Khalil Y. F. El-Aryan I. M. Ali 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(2):359-369
A study on the sorption of Zn2+, Ni2+ and Co2+ onto mixed oxide of Mn and Fe obtained at different hydrothermal conditions and its organic hybrid film modified with polyacrylamide (Mn–Fe oxide/PAM) has been examined. The characterization of inorganic oxides and its composite samples were performed using XRD, SEM, FTIR, XRF and DTA-TGA techniques. The percent sorption of Zn2+, Ni2+ and Co2+ on Mn–Fe oxide at pH 4.5 was 97, 11.85 and 10 % respectively with selectivity order Zn2+ ? Ni2+ > Co2+. The sorption value of Zn2+ at pH 4.5 onto Fe–Mn oxide reached nearly the same value of Zn2+ onto its composite. So, the new compound of Fe–Mn oxide has promising uses for separation of zinc ions while its composite can be used for removal all of these cations. 相似文献
6.
A. P. Savikin A. S. Egorov A. V. Budruev I. A. Grishin 《Glass Physics and Chemistry》2016,42(5):473-479
Visualization of infrared radiation of Tm:YLF-laser at the wavelength of 1908 nm has been investigated in the glass and ceramics samples with compositions of 53ZrF4 · 20 BaF2 · 1HoF3 · 3YbF3 · 3AlF3 · 20NaF and 53ZrF4 · 20BaF2 · 3LaF3 · 1HoF3 · 3AlF3 · 20NaF (mol %). In luminescence spectra of ZBLAN samples doped with Но3+, the bands at the wavelengths of 480, 540, and 650 nm were observed, which correspond to 5 F 3 → 5 I 8, 5 S 2, 5 F 4 → 5 I 8, and 5 F 5 → 5 I 8 electron transitions in Но3+ ions with the maximum intensity of the red band (650 nm). Occupancy of the 5 S 2 and 5 F 4 levels in the ZBLAN: 1% Но3+ samples is related to the sequential absorption of the exciting radiation quanta. The level of 5 F 5 is filled mainly due to the ionic interaction. Additional doping with the Yb3+ ions led to the change of the luminescence color to green and a decrease in the threshold radiation power density of the Tm:YLF-laser in ceramic samples up to 2 W/cm2. 相似文献
7.
Fatma H. El-Batal Amany A. El-Kheshen Abeer A. Abd El Aty Gehan T. El-Bassyouni 《SILICON》2018,10(4):1231-1241
Derived Hench’s bioglasses with specific ionic dopants Ag+, Cu2+, or Zn2+ have been prepared. The bone-boding ability or bioactivity behavior for the prepared glasses and their glass-ceramic derivatives has been investigated after immersion in phosphate solution for two weeks. Collective Fourier transform infrared absorption spectra (FTIR) and scanning electron microscopic (SEM) studies were conducted in order to study the in-vitro bioactivity behavior. X-ray diffraction (XRD) analysis was carried out to identify the crystallized phases upon thermal heat treatment through a two-step regime. The glasses and their glass-ceramic derivatives were tested to study their antibacterial or antifungal efficiency responding to the doped metal ions. FTIR spectra revealed the generation of two split peaks at about 560 and 605 cm?1, after immersion in (0.2 M) sodium phosphate solution (Na3PO4), signifying the formation of a crystalline calcium phosphate phase, leading to hydroxyapatite formation. SEM examinations show characteristic rounded or nodular microcrystals for hydroxyapatite which support the FTIR data. X-ray diffraction analysis indicated crystallization of the main soda-lime silicate phase (1Na2O.2CaO.3SiO2) besides a secondary silicon phosphate phase (SiO2.P2O5) in the studied glass ceramics. The route of crystallization is discussed on the basis of the presence of 6% P2O5; which facilitates the formation of phase separation and voluminous bulk crystallization of the main soda-lime silicate phase. The introduction of dopants is identified to cause no changes in the precipitated phases, with only minor changes in the percent of the crystalline phases. Experimental data indicate that the glass-ceramic samples are effective in bioactivity and antimicrobial efficiency. 相似文献
8.
Hong Li Liwang Liu Xiaozhe Tang Qian Wang Dehua Xiong 《Glass Physics and Chemistry》2018,44(4):300-306
Tb3+-doped SrO–Al2O3–SiO2 glass-ceramics are prepared by melting under ambient atmosphere and followed by two-step heat treatment approach. Extensive differential thermal analysis, X-ray diffraction and scanning electron microscope characterizations are applied to investigate thermal properties, crystal structure, and morphology of these glass-ceramics. The results indicate that the optimal ratio of two nucleation agents (TiO2 and ZrO2) is 3:1 (molar fraction) in glass-ceramics. In addition, several heat treatment schedules are developed to study the influence of treatment temperature on luminescence properties of Tb3+- doped glass-ceramics. The results demonstrate that there are four emission bands located at 489, 547, 588 and 623 nm under 376 nm ultraviolet excitation, corresponding to 5D4 → 7Fj (j = 6, 5, 4, 3) transitions of Tb3+, respectively. At last, the corresponding chromaticity coordinates are calculated and constructed, which indicates that the Tb3+ glass-ceramic can emit approximate white light under 376 nm ultraviolet excitation when they nucleated at 950°C and crystallized at 1050°C. The white immersion approached standard illuminant C as the crystallization temperature increased. 相似文献
9.
Sm3+-doped SrO–Al2O3–SiO2 glass-ceramics with excellent luminescence properties were prepared by batch melting and heat treatment. The crystallization behavior and luminescent properties of the glass-ceramics were investigated. The results indicate that the crystal phase in this system is monocelsian (SrAl2Si2O8). Under the excitation with blue light (475 nm) the Sm3+-doped SrO–Al2O3–SiO2 glass-ceramics emit green, orange and red lights centered at 565, 605, 650 and 715 nm, which can be assigned to the 4G5/2 → 6HJ/2 (J = 5, 7, 9, 11) electron transitions in Sm3+ ions, respectively. With the increase of nucleation/crystallization temperature, the crystallite part rises from 66 to 79%. Besides, by increasing crystallization temperature or concentration of Sm3+, the samples emission located at 565, 605 and 650 nm is intensified significantly. We envision that, by fine controlling and combining of these three (green, orange and red) lights in an appropriate proportion, the Sm3+-doped glass-ceramics are promising luminescence materials for white light-emitting diodes devices. 相似文献
10.
The concentration and the type of Cu2+ species adsorbed on a natural zeolite (Clinoptilolite) was measured and studied by using Electron Paramagnetic Resonance
Spectroscopy (EPR). The EPR results together with macroscopic sorption data indicate that the solution ionic strength as well
as, the type of electrolyte anion (Cl−, NO3− and SO42− ions were examined) affect the amount of Cu adsorbed and the type of Cu surface complexes. The increasing in solution pH
affects Cu adsorption quantitatively whereas; the type of surface complexes formed depends mainly on solution ionic strength.
For low solution ionic strength, when the inhibition from solution species is limited, the adsorbed Cu is characterized by
more than one type of chemical environment. On the contrary, for high solution ionic strength the Cu adsorption is inhomogeneous
and EPR spectra show only one type of surface complex. When the anions of the background electrolytes are different, but of
equal normality, the results indicate that in the presence of SO42− discernible Cu surface complexes are formed whereas, for Cl− and NO3− these surface formations are obtained only for high Cu adsorbed concentrations. 相似文献
11.
Syed Ashfaq Nabi Sajad Ahmad Ganai Amjad Mumtaz Khan 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(1):25-35
Polyaniline stannic silicomolybdate, an organic–inorganic composite material was synthesized by mixing polyaniline, an electrically
conducting organic polymer into the matrices of inorganic precipitate of stannic silicomolybdate. The experimental parameters
such as mixing volume ratio and pH were established for the synthesis of the material. The material was found granular, thus
suitable for column operations. Polyaniline stannic silicomolybdate shows better ion exchange capacity and thermal stability.
The exchanger was characterized on the basis of instrumental techniques such as FTIR, TGA, DTA XRD and SEM. The X-ray diffraction
study showed semi-crystalline nature. The elution behavior of the material was also examined. The SEM micrographs show the
difference in surface morphology of inorganic component and the composite material. Distribution coefficient studies were
performed for different metal ions in varied solvent systems such as Triton X-100, trichloroacetic acid and acetic acid. The
effect of temperature on the distribution coefficient was also studied. It was found that 40 °C appeared to be the most suitable
temperature. The material was found to be selective for Pb2+ ion. On the basis of distribution coefficient values, some analytically important binary separations of metal ions viz. Mg2+–Pb2+, Zn2+–Pb2+, Cd2+–Pb2+ and Mg2+–Cu2+ were achieved on polyaniline stannic silicomolybdate columns. The practical utility of polyaniline stannic silicomolybdate
was explored by achieving quantitative separation of Pb2+ in industrial waste effluents from battery manufacturing units. 相似文献
12.
The single-crystals of Ca2+, K+-exchanged zeolite Y, and Ca2+, Rb+-exchanged zeolite Y were prepared by using flow method with mixed ion-exchange solution, whose Ca(NO3)2:KNO3 mole ratios were 1:1 (crystal 1) and 1:100 (crystal 2), and Ca(NO3)2:RbNO3 mole ratios were 1:1 (crystal 3) and 1:100 (crystal 4), respectively, with a total concentration of 0.05 M. They were fully dehydrated by vacuum dehydration at 723 K and 1 × 10?6 Torr for 2 days. Their crystals were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group \(Fd \overline{3}\) m, respectively, and were refined to the final error indices R 1/wR 2 = 0.057/0.196, 0.073/0.223, 0.055/0.188, and 0.049/0.175 for crystals 1, 2, 3, and 4, respectively. In the structure of crystal 1 (|Ca23K29|[Si117Al75O384]-FAU), 23 Ca2+ ions per unit cell occupy sites I, II′, and II; 29 K+ ions per unit cell are at sites II′, II, and III′. In the structure of crystal 2 (|Ca18.5K38|[Si117Al75O384]-FAU), 18.5 Ca2+ ions per unit cell occupy sites I, I′, and II; 38 K+ ions are at sites I′, II, and III′. In the structure of crystal 3 (|Ca27Rb21|[Si117Al75O384]-FAU), 27 Ca2+ ions per unit cell occupy sites I, II′, and II; 21 Rb+ ions per unit cell are at sites II′, II, and III. In the structure of crystal 4 (|Ca18Rb39|[Si117Al75O384]-FAU), 18 Ca2+ ions per unit cell occupy sites I and II; 39 Rb+ ions per unit cell are at sites I′, II′, II, III, and III′. In the four crystals, the Ca2+ ion which has much smaller size and higher charge than other cations such as K+ and Rb+ energetically preferred at site I and so the first to be filled on it. Unlike Ca2+ ion, no K+ and Rb+ ions are found at site I, which are clearly less favorable for K+ and Rb+ ions. 相似文献
13.
B. Rajesh Babu M. S. R. Prasad K. V. Ramesh Y. Purushotham 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(3):589-597
The effect of Al substitution on electrical and dielectric parameters of Ni–Zn ferrite has been discussed in the present work. The phase identification, surface morphology was studied using X-ray diffractometer (XRD), scanning electron microscope (SEM), respectively. The XRD patterns confirm the single-phase formation of these ferrites. With Al3+, substitution lattice parameter decreases due to smaller Al3+ ions replacing Fe3+ ions. The average grain size obtained from SEM results are in the range of 390–27 nm. The DC resistivity was observed to increase with increasing Al3+ ions concentration due to the unavailability of Fe3+ ions. Dielectric constant (\(\upvarepsilon ^{\prime }\)) and dielectric loss tangent (tan δ) have been studied as a function of frequency (1 kHz–10 MHz) and temperature (50–300 °C). The observed results are explained on the basis of interfacial polarization as predicted by Maxwell and Wagner. 相似文献
14.
Atlantic salmon were fed fish meal-based diets supplemented with either 100% fish oil (FO) or 100% rapeseed oil (RO) from
an initial weight of 85 g to a final average weight of 280 g. The effects of these diets on the capacity of Atlantic salmon
hepatocytes to elogate, desaturate, and esterify [1-14C]18∶1n−9 and the immediate substrates for the Δ5 desaturase, [1-14C]20∶3 n−6 and [1-14C]20∶4n−3, were investigated. Radiolabeled 18∶1n−9 was mainly esterified into cellular TAG, whereas the more polyunsaturated
FA, [1-14C]20∶3n−6 and [1-14C]20∶4n−3, were primarily esterified into cellular PL. More of the elongation product, [1-14C]20∶1n−9, was produced from 18∶1n−9 and more of the desaturation and elongation products, 22∶5n−6 and 22∶6n−3, were produced
from [1-14C]20∶3n−6 and [1-14C]20∶4n−3, respectively, in RO hepatocytes than in FO hepatocytes. Further, we studied whether increased addition of [1-14C]18∶1n−9 to the hepatocyte culture media would affect the capacity of hepatocytes to oxidize 18∶1n−9 to acid-soluble products
and CO2. An increase in exogenous concentration of 18∶1n−9 from 7 to 100 μM resulted in a nearly twofold increase in the amount of
18∶1n−9 that was oxidized. The conversion of 20∶4n−3 and 20∶3n−6 to the longer-chain 22∶6n−3 and 22∶5n−6 was enhanced by RO
feeding in Atlantic salmon hepatocytes. The increased capacity of RO hepatocytes to produce 22∶6n−3 was, however, not enought
to achieve the levels found in FO hepatocytes. Our data further showed that there were no differences in the hepatocyte FA
oxidation capacity and the lipid deposition of carcass and liver between the two groups. 相似文献
15.
This article reviews the utility of dioxiranes in the oxidation of 3beta-substituted delta5-sterols. Dioxiranes are the smallest cyclic peroxides that contain a carbon atom. They can be generated in situ from Oxone (2KHSO5.KHSO4.K2SO4) and a ketone. Dioxiranes are versatile oxidizing agents. The most common reaction of dioxiranes is epoxidation, with nearly 1:1 ratios of alpha/beta isomer products in all cases. delta5-Steroids with different side chains were epoxidized by dioxiranes generated in situ from several commercially available ketones. Although ketones function as catalyst, they were used in about an equivalent amount or large excess to accelerate the reaction. 相似文献
16.
The catalytic oxidation of propane was studied in an oxygen ion conducting solid electrolyte cell at 623–773 K and atmospheric
total pressure. Three catalyst-electrodes were tested, Pt, Pd and Ag. Under open circuit, the technique of Solid Electrolyte
Potentiometry (SEP) was used to monitor the thermodynamic activity of oxygen adsorbed on the catalyst surface during reaction.
Under closed circuit, the effect of electrochemical promotion was investigated. On Pt and Pd, the promoting effect was of
the “inverted volcano” type. On Pt, the reaction exhibited a strong NEMCA effect; the closed circuit rate exceeded the open
circuit rate by more than three orders of magnitude. On Pd, on the other hand, the effect was hardly Faradaic. On Ag, a moderate
NEMCA behavior was observed and the promoting effect was purely electrophobic. Both open and closed circuit results obtained
with these three catalyst-electrodes, are evaluated and compared to each other. 相似文献
17.
Lianwei Shan Jun Ding Wenli Sun Zhidong Han Liguo Jin 《Journal of Inorganic and Organometallic Polymers and Materials》2017,27(6):1750-1759
To enhance the photocatalytic activity of monoclinic scheelite (ms) BiVO4 for dye degradation, the heterostructured core (BiVO4)/shell (BiVO4:Eu3+) samples were synthesized by sol–gel method. The samples were characterized by UV–Vis diffuse reflectance spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS). The results reveal that as-synthesized photocatalysts are characteristic of ms core/shell structure, responsive to visible light. The XPS spectra confirm that the doped Eu3+ mainly distributed in the outside layer of BiVO4 particle. The valence band (VB) spectra indicate the shell (BiVO4:Eu3+) exhibits a high carrier mobility. The core/shell photocatalysts showed higher photocatalytic activity than pure BiVO4 through degrading Rhodamine B and Methylene blue. The better performance of core/shell heterojunction mainly results from that the Eu3+ ions selectively present on shell layer, increasing the VB value of shell layer (forming a interface electric field with core) and carrier mobility. It is considered that the half-filled 7f–electron configuration of Eu3+ can improve the electron trapping and transfer. Besides, the low PL intensity and high SBET of BiVO4/BiVO4:Eu3+ contribute to enhanced photocatalytic performances. 相似文献
18.
Summary
Novel poly(p–phenylenevinylene)–based (6–arene)Cr(CO)3–containing polymers
including the alkyldiphenylamine or triarylamine units in the main chain were
synthesized by the Homer–Wadsworth–Emmons coupling reaction. The structures of
the polymers were confirmed by NMR and FT–IR spectra. The polymers were soluble
in common organic solvents such as THF, CHCl3, and CH2Cl2. The polymer showed
interaction between the electron–withdrawing (6–arene)Cr(CO)3 unit and the
unshared electron pair on the nitrogen atom along the polymer backbone. 相似文献
19.
Four single crystals of fully dehydrated and partially Zn2+-exchanged zeolites Y (Si/Al?=?1.56) were prepared by the static ion-exchange method using a mixed ion-exchange solution in which Zn(NO3)2:NaCl mole ratios were 1:1 (crystal 1), 1:25 (crystal 2), 1:50 (crystal 3), and 1:100 (crystal 4), respectively, with a total concentration of 0.05 M, and followed by vacuum dehydration at 673 K. Their single-crystal structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd\(\bar {3}\)m and refined to the final error indices R1/wR2?=?0.0459/0.1454, 0.0449/0.1283, 0.0427/0.1284, and 0.0486/0.1680, respectively. Their unit-cell formulas are |Zn25Na25|[Si117Al75O384]-FAU (crystal 1), |Zn19.5Na36|[Si117Al75O384]-FAU (crystal 2), |Zn19.5Na36|[Si117Al75O384]-FAU (crystal 3), and |Zn7Na61|[Si117Al75O384]-FAU (crystal 4), respectively. The degree of Zn2+ exchange decreases from 67 to 19% as the initial concentration of Zn2+ decrease and the initial concentration of Na+ increases in given ion-exchange solutions. 相似文献
20.
The effect of cysteine (RSH), methionine (CH3SR), cystine (RSSR) and N-acetylcysteine (ACC) on the corrosion behavior of mild steel in 40% H3PO4 solution without and with Cl−, F−, Fe3+ and their ternary mixture was studied using both potentiostatic and electrochemical impedance (EIS) techniques under anodic and cathodic polarization conditions. The inorganic additives stimulate the overall corrosion reaction while the amino acids inhibit it with a predominant effect on the dissolution of iron. Both RSH and ACC are adsorbed according to Temkin’s isotherm while adsorption of RSSR and CH3SR follows Frumkin and Langmuir isotherms respectively. The standard free energy of adsorption (ΔG
) was found to be in the order: RSSR > RSH ≅ ACC > CH3SR. The binary mixtures of Cl− or F− with RSH or CH3SR are the best inhibitors (IE > 90%) while those containing ferric ions or blend I and amino acids are not good corrosion inhibitors. EIS measurements showed that the cathodic reaction, hydrogen evolution, is charge transfer controlled while the anodic one, iron dissolution, is a complex process. 相似文献