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1.
In this research, waste cow bone was chosen as a sustainable source of biomaterials in pure hydroxyapatite form and synthesized hydroxyapatite (HAP) was prepared as a biphasic HAP (hydroxyapatite and β-tricalcium phosphate phase) and subsequently pure β-tricalcium phosphate (β-TCP). The samples were characterized by employing X-Ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) instrumentation, and in-depth crystallographic analysis was performed by calculating crystallite size, lattice parameters, HAp percentage, the volume fraction of β-TCP, β-TCP percentage, crystallinity index, degree of crystallinity, microstrain, and dislocation density. Excellent results was noticed for biocompatible properties such as cytotoxicity, hemolysis, and antimicrobial (E. coli, S. aureus, and A. niger). A relationship was established among the synthesized products and the crystallographic parameters.  相似文献   

2.
Ion-chromatography (IC) as well as high performance liquid chromatography (HPLC) techniques have been used as analytical tools for the separation and estimation of some of the relevant metal ions present in the high level liquid waste (HLLW). IC was applied for the estimation of alkali and alkali earth metal ions, viz. Na, Cs, Ba and Sr using methane sulphonic acid as the eluent on a cation exchange column. On the other hand, dynamically modified (with sodium salt of n-octane sulphonic acid) reverse phase HPLC was followed for the estimation of lanthanides viz. La, Pr, Nd and Sm using α-hydroxy isobutyric acid as the eluent on a C-18 column. Sample acidity of 0.01 M HNO3 was optimized for best analytical results. The interferences of one group of metal ions on the quantification of the other group of metal ions were studied. The solvent extraction data (distribution coefficient data) of Na, Cs, Sr, Ba, La, Pr, Nd and Sm from their mixture was obtained by analyses of the aqueous samples before and after extraction with extractants used for actinide partitioning, viz., octyl(phenyl)N,N-diisobutyl carbamoyl methylene phosphine oxide (CMPO), N,N′-dimethyl-N,N′-dibutyl tetradecyl malonamide (DMDBTDMA) and N,N,N′,N′-tetraoctyl diglycolamide (TODGA). The solvent extraction data obtained by IC/HPLC techniques was compared with those obtained by ICP-AES technique. A good agreement between the results of the two techniques validated the present analytical method.  相似文献   

3.

Huge amounts of granite wastes have been generated in the granite-processing industry and should be properly disposed to reduce the negative impacts on the environment and health care. In this work, waste granite powder was modified and sintered to prepare high-strength and tough glass–ceramics. The heating rate was studied to clarify its effects on the sinterability, crystallization, and mechanical properties of glass–ceramics. With the increase in heating rate, the densification of sintered glass–ceramics was promoted by the liquid glassy phase from the microcline phase. The glass–ceramics were strengthened and toughened simultaneously due to the improved densification and increased crystallinity. The toughening mechanism was attributed to the crack bridging, deflection, and branching. The maximum flexural strength of 143 MPa and fracture toughness of 2.1 MPa m1/2 were achieved with a heating rate of 50 °C min−1, far superior to that of natural granite. The crystal structure of sintered glass–ceramics indicated the main crystalline phase of anorthite. These glass–ceramics with excellent mechanical properties promise the practical reutilization of granite wastes in the construction tiles.

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4.
Waste utilization is not only the protection of the environment and the practice of green chemistry, but also one of the ways to develop new materials. Herein, we report two biomass carbon dots which prepared from bee pollen waste by one-step hydrothermal method. The new two carbon dots were used in sensing, cell imaging and plant growth regulation. The differences in the structure and properties of the two carbon dots were evaluated by TEM, XPS, TG and various spectroscopic methods. Both two ca...  相似文献   

5.
Waste utilization is not only the protection of the environment and the practice of green chemistry, but also one of the ways to develop new materials. Herein, we report two biomass carbon dots which prepared from bee pollen waste by one-step hydrothermal method. The new two carbon dots were used in sensing, cell imaging and plant growth regulation. The differences in the structure and properties of the two carbon dots were evaluated by TEM, XPS, TG and various spectroscopic methods. Both two ca...  相似文献   

6.
Research on Chemical Intermediates - Novel copper complexes were prepared from acetanilide derivatives and deliberately characterized. The molar ratio obtained was 1:1 through neutral bi-dentate...  相似文献   

7.
A rapid separation method has been developed which allows measurement of plutonium, americium and strontium isotopes in the radioactive sludge from Nuclear power plant A1 Jaslovske Bohunice (NPP A1) with high chemical recoveries and effective removal of matrix interferences. This method uses different commercial products stacked AnaLig? Pu02, AnaLig? Sr01 and TRU? Resin cartridges from IBC Advanced Technologies and Eichrom Technologies. The method allows the rapid separation of plutonium, strontium and americium using a single multi-stage column in the vacuum box (cartridge technology) with rapid flow rates to minimize sample separation time. The 239,240Pu, 238Pu and 241Am were determined by alpha spectroscopy, 90Sr was counted on TRICARB 2900 TR by Cerenkov counting of its progeny 90Y.  相似文献   

8.
A rapid separation method has been developed which allows measurement of plutonium, americium and strontium isotopes in the high active sample from CBRN Training and Testing Centre in Zemianske Kostolany (Slovakia) with high chemical recoveries and effective removal of matrix interferences. This method uses different commercial products stacked AnaLig® Pu-02, AnaLig® Sr-01 and DGA® Resin cartridges from IBC Advanced Technologies and Eichrom Technologies. The method allows rapid separation of plutonium, strontium and americium using a single multi-stage column in the vacuum box (cartridge technology) with rapid flow rates to minimize sample separation time. The 239,240Pu, 238Pu and 241Am were determined by alpha spectroscopy, 90Sr was counted on TRICARB 2900 TR by Cerenkov counting of its progeny 90Y.  相似文献   

9.
A validated method based on solid-phase extraction (SPE) and liquid chromatography-ion trap tandem mass spectrometry (LC-MS/MS) is described for the determination of cocaine (COC) and its principal metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME), in waste and surface water. Several SPE adsorbents were investigated and the highest recoveries (95.7 +/- 5.5, 91.8 +/- 2.2 and 72.5 +/- 5.3% for COC, BE and EME, respectively) were obtained for OASIS HLB(R) cartridges (6 mL/500 mg) using 100 mL of waste water or 500 mL of surface water. Extracts were analysed by reversed-phase (RP) or hydrophilic interaction (HILIC) LC-MS/MS in positive ion mode with multiple reactions monitoring (MRM); the latter is the first reported application of the HILIC technique for drugs of abuse in water samples. Corresponding deuterated internal standards were used for quantification. The method limits of quantification (LOQs) for COC and BE were 4 and 2 ng L(-1), respectively, when RPLC was used and 1, 0.5 and 20 ng L(-1) for COC, BE and EME, respectively, with the HILIC setup. For COC and BE, the LOQs were below the concentrations measured in real water samples. Stability tests were conducted to establish the optimal conditions for sample storage (pH, temperature and time). The degradation of COC was minimal at -20 degrees C and pH = 2, but it was substantial at +20 degrees C and pH = 6. The validated method was applied to a set of waste and surface water samples collected in Belgium.  相似文献   

10.
The decomposition reaction process of waste rare earth (RE) polishing powder was monitored in real time by the thermogravimetry?Cdifferential thermal analysis (TG?CDTA) and Fourier transform infrared spectroscopy (FTIR). The results showed that the reaction was divided into two stages, and the thermal weight losses got to stable when the temperature was more than 400?°C. The releasing gas mainly contained H2O and SiF4, and the reaction kinetics during decomposition process was studied by the methods of Freeman-Carroll and Kissinger.  相似文献   

11.
Gamma-radiolysis of the parent compound N-(2-hydroxyethyl)ethylenediamine-triacetic acid (HEDTA) in a simulant of a Hanford mixed waste, at γ-doses of 0–7.5·106±10% R, yielded extensive degradation. Two major degradation products, glyoxylate and N-(nitroso)iminodiacetic acid (NIDA), were identified, along with lower levels of malonate and oxalate. Comparison of HEDTA’s radiolysis with that of ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA) and citrate, from earlier studies, reveals several fundamental similarities, along with marked differences. Comparatively speaking, HEDTA’s radiolysis is not particularly diverse, but it is very dispersive.  相似文献   

12.
The effects of two solid-based hydrogen peroxides sodium percarbonate(SPC) and calcium peroxide(CP)on waste activated sludge(WAS) disintegration were investigated. Both oxidants achieved efficient WAS disintegration for the synergistic effect of alkaline and oxidation. The strong alkaline condition led to the leakage of ammonia and the existence of abundant calcium ions accelerated the fixation of phosphorus via precipitation in CP WAS disintegration process. However, the spongy-like layer and l...  相似文献   

13.
The effects of two solid-based hydrogen peroxides sodium percarbonate(SPC) and calcium peroxide(CP)on waste activated sludge(WAS) disintegration were investigated. Both oxidants achieved efficient WAS disintegration for the synergistic effect of alkaline and oxidation. The strong alkaline condition led to the leakage of ammonia and the existence of abundant calcium ions accelerated the fixation of phosphorus via precipitation in CP WAS disintegration process. However, the spongy-like layer and l...  相似文献   

14.
Municipal wastewater has been examined for steroids, β2-agonists, stimulants, diuretics, and phosphodiesterase type V inhibitors (PDE type V inhibitors), which are “dual-use-drugs” applied either as anabolic, doping, and lifestyle drugs or for treatment of diverse diseases. To identify their origin, fitness centre discharges under suspicion of being point sources and sewage-treatment plant feed and effluents were sampled and concentrations determined. Sensitive and selective methods for determination and quantification based on solid-phase extraction (SPE) followed by high-performance liquid chromatography–high resolution mass and tandem mass spectrometry (HPLC–(HR)MS and HPLC–MS–MS) were developed and established for analysis of these compounds in wastewater and to assess their effect on the environment. The methods developed enabled quantification at trace concentrations (limit of quantification (LOQ): 5 ng L−1). Of the steroids and stimulants under investigation, testosterone, methyltestosterone, and boldenone or ephedrine, amphetamine, and MDMA (3,4-methylendioxy-N-methylamphetamine) were observed at up to 5 μg L−1 (ephedrine). Of the β2-agonists salbutamol only, and of the diuretics furosemide and hydrochlorothiazide were confirmed in the extracts. Quite high concentrations of the PDE type V inhibitors sildenafil, tadalafil, and vardenafil and their metabolites were confirmed in fitness centre discharges (sildenafil: 1,945 ng L−1) whereas their concentrations in municipal wastewater did not exceed 35 ng L−1. This study identified anabolic and doping drugs in wastewater for the first time. Results obtained from wastewater treatment plant effluents proved that these “dual-use-drugs”, with the exception of hydrochlorothiazide, were mostly eliminated.  相似文献   

15.
We have developed a metal and halogen-free Friedel–Crafts acylation protocol with virtually no waste stream generation. We propose a hydrogen bonding donor solvent will form a hydrogen bonding network and may provide significant rate enhancement for Friedel–Crafts reactions. Trifluoroacetic acid is one of the strongest H-bond donor solvents, which is also volatile and can be easily recovered by distillation without need for reaction workup. Our protocol is a ‘green’ Friedel–Crafts acylation process: 1) the catalyst can be recovered and reused; 2) using halogen free starting material (carboxylic acids anhydride or carboxylic acids); 3) no need for aqueous reaction work-up; 4) minimum or no waste steam generation.  相似文献   

16.
A consideration of equilibrium model-based equations suggests that tautomeric equilibria do not markedly affect observed potency if the tautomer bound represents at least 50% of the compound in solution. Tautomeric equilibria can enhance or attenuate the correlation of potency with Hammett σ. Additionally, tautomeric equilibria can lead to a correlation of potency with σ even in the absence of a correlation of binding with σ.  相似文献   

17.
In this paper, N-doped carbon quantum dots (N-CDs) were fabricated using crown daisy leaves, a kitchen waste, as carbon source. The synthesized N-CDs possessed abundant surface functional groups, such as hydroxyl, carboxyl, and amino groups, and had good dispersibility in water. Because of the special fluorescence quenching property toward Cu2+, the synthesized N-CDs can be exploited as an effective label-free fluorescent probe for Cu2+ determination. The possible fluorescence sensing mechanism considered the selective coordination interaction between Cu2+ ion and the hydroxyl, carboxyl, and amino groups of the N-CDs. The control experiments also showed that the N-doped aromatic C–N heterocycle structure played a crucial role in selective sensing of Cu2+. The decrease in fluorescence efficiencies was linearly related with the Cu2+ concentrations in the range of 10.0nM to 120.0nM, with a response limit of 1.0nM. The prepared probe was also applied for Cu2+ determination in real river water.  相似文献   

18.
The densities (ρ), viscosities (η), ultrasonic speeds (u) and spectroscopic data of binary mixtures of benzene, toluene, m-xylene and mesitylene with β-pinene as a common component, over the whole composition range of mole fraction of β-pinene including those of pure components, have been measured at 303.15, 308.15 and 313.15 K, except for the spectroscopic study where the temperature was maintained at 298.15 K. The experimental results deviation in viscosity, deviation in ultrasonic velocity, isentropic compressibility and deviation in isentropic compressibility are discussed in terms of molecular interactions between unlike molecules. The variation of these excess parameters indicates the presence of weak interactions between β-pinene and benzene, toluene, m-xylene and mesitylene molecules. Moreover, the viscosity data are discussed in terms of interaction parameters. The theoretical ultrasonic speed was computed using the Nomoto model, ideal mixing relation, Jacobson’s free length theory and compared with the experimentally measured values. The experimental values are also discussed in terms of FTIR spectroscopy.  相似文献   

19.
Nesquehonite, hydromagnesite, and brucite are important precursors for the preparation of high-purity magnesia (MgO) using magnesium resources from salt lake as raw materials. In this paper, TG–DTG and DSC were used to investigate the thermal decomposition behaviors of the three precursors. Decomposition kinetic parameters at each stage were evaluated based on the TG data using the iso-conversional method. Decomposition mechanisms were determined using the master-plots method. The decomposition temperature range, heat absorption, and kinetic parameters of the three phases were then compared. The most probable mechanism of each stage from the perspective of crystal structure was found to be consistent with the calculation results from the master-plots method. Results led to the conclusion that nesquehonite is the most appropriate precursor for the preparation of high-purity MgO. Further studies on precursor selection and calcining condition selection for the preparation of MgO using bischofite will benefit from this research.  相似文献   

20.
The reactions of terpene nitrosochlorides derived from 3-carene, ??-pinene, and limonene, with simplest azaheterocycles (imidazole, benzotriazole, and indole) were studied. On the base of these transformations, preparative procedures to access chiral oximes bearing azaheterocyclic moieties in the ??-position to the oxime fragment, namely, ??-(1H-imidazol-1-yl)-, ??-(1H-benzo-[d][1,2,3]triazol-1-yl)-, and ??-(1H-indol-3-yl)-substituted terpenic oximes, were developed. Transformations of the studied monoterpene nitrosochlorides into ??-substituted oximes proceeded stereoselectively to give in the moderate yields (30?C60%) the only stereoisomer arising from the attack of the heterocyclic anion from the less hindered side of the intermediate nitroso olefin generated in situ from nitrosochloride.  相似文献   

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