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1.
The reprocessing of endoscopes is a complex procedure due to their structural design. In the constant search for new antimicrobial substances, recent studies with ozone have yielded great benefits. The present study evaluated the effects of ozonated water used to disinfect endoscopes comparing its efficacy with the conventional technique (2% glutaraldehyde). According to the results obtained, when ozonated water was used (330 mg.min.L?1), induced a 2 log reduction of the viable microorganisms under the conditions tested. Ozonated water was a potent gastrointestinal endoscopic sanitizer, suggesting it is a feasible alternative for disinfection.  相似文献   

2.
This study tested the efficacy of ozone in a CIP system of a wine industry, for that, a hose that transported wine was submitted to the following treatments: ozonated water at 28 ± 1 °C (in concentrations of 0.38 and 1.03 ppm for one, five and nine minutes); hot water (85 ± 1 °C for 15 minutes); peracetic acid (0.3% for 15 minutes); and a caustic soda solution (2%) with peracetic acid (0.3% for 15 minutes). The results indicate that the use of ozonated water is more effective than the isolated use of peracetic acid and the combined use of soda and peracetic acid.  相似文献   

3.
Norbornyl epoxidized linseed oil was synthesized via Diels-Alder reaction of cyclopentadiene with linseed oil at high pressure (∼200 psi) and high temperature (240 °C), followed by an epoxidation using hydrogen peroxide with a quaternary ammonium tetrakis(diperoxotungsto) phosphate(3−) epoxidation catalyst. The products were characterized using 1H and 13C NMR, FT-IR, and electrospray ionization mass spectroscopy. Photo-induced curing kinetics of norbornyl epoxidized linseed oil coatings was investigated using real-time FT-IR spectroscopy with a fiber optic UV-curing system. The norbornyl epoxidized linseed oil was formulated with three different divinyl ether reactive diluent. The effect of divinyl ether concentration and types of divinyl ether on the curing reaction was investigated. It was found that the curing rate of norbornyl epoxidized linseed oil was lower than that of cycloaliphatic epoxide, but higher than epoxidized linseed oil. The incorporation of divinyl ethers increased the curing rate and overall conversion of the epoxide groups. Of the three divinyl ethers used, coating with triethyleneglycol divinyl ether showed the highest curing rate and coating with cyclohexane dimethanol divinyl ether showed the lowest curing rate.  相似文献   

4.
Robust, routine, and rapid instrumental methods for the determination of the authenticity of edible oils, and the detection of adulteration, are continually being sought. In this paper, we compare mid-infrared and Raman spectroscopies for their ability to discriminate between oils of differing botanical origin and for their ability to detect added adulterants. Furthermore, we used sufficient numbers of samples to permit a comparison of some of the chemometric methods (linear discriminant analysis, artificial neural networks) available and looked at the results obtained when the two spectroscopic datasets were combined. We show that mid-infrared spectroscopy, in combination with linear discriminant analysis, gave the best classification rates and adulteration detection levels compared to Raman or combined data.  相似文献   

5.
The ozonation of vegetable oils has been studied, since the produced ointments have antibacterial and fungicidal activities. However, the ozonation of mineral oils has not been reported in the literature yet, opening an interesting field for examination. In this work, we have shown the ozonation of a commercial mineral oil (Nujol). The main goal was to produce oils containing free ozone, so that this gas could act as antimicrobial agent. It was found that in Nujol, ozone remains for at least 40 days and in the sample ozonized for 15 h its concentration was 7.5 mg mL?1. Neat Nujol showed no antimicrobial activity against the tested microorganisms, however, when ozonated it showed antimicrobial activity against Enterococcus faecalis, Staphylococcus aureus and Escherichia coli.  相似文献   

6.
近红外光谱在油品快速分析中的应用   总被引:1,自引:0,他引:1  
各项性能指标合格的油品是用油机械正常运行的前提和保证。因此,油品性质的快速检测具有重要的经济和军用价值。阐述了傅立叶变换近红外光谱技术测定油品多项物理性质的原理,介绍了其与化学计量学相结合进行油品快速分析的方法,综述了近红外光谱技术在油品快速分析领域中的应用现状,最后展望了其发展方向。  相似文献   

7.
Thermooxidation at 100°C and photooxidation at wavelengths above 300 nm of dried oil films were evaluated. The chemical modifications of the networks were determined by infrared analysis coupled with gaseous treatments (NO, SF4, and NH3). The dried films are rather stable in thermooxidation, whereas in photooxidation, important degradation of the network occurs with many chain scissions. This photoinstability results from the presence of crosslinks that are sensitive to radical attack because of the lability of the hydrogen atom on the tertiary carbons. The photooxidation reactions are fully described in this paper. Yellowing of the cured samples, observed with ultraviolet-visible and fluorescence spectrometries, rapidly is decreased by irradiation because the oil contaminants that are mainly responsible for the yellowness are photooxidized. On the contrary, yellowing slowly but continuously increases during thermooxidation at 100°C.  相似文献   

8.
ABSTRACT

Root-knot nematodes (Meloidogyne incognita) are plant parasitic worms that widely influence the agricultural production including soilless cultivation. In this study, we investigated the inactivating effect of ozonated nutrient solution on the root-knot nematode juveniles in both nutrient solution and substrate, as well as the in vitro egg hatching. The results showed that twice ozonation treatments with dissolved ozone concentration (DOC) at 0.5 mg/L resulted in a mortality at 90.8% for in vitro study. DOC of 4.0 mg/L with three treatment repeats in the substrate experiment resulted in a mortality at 88.3%. Our results imply that the application of ozonated nutrient solution might be a feasible method in soilless cultivation for the control of root-knot nematodes. In practical application, ozonation treatment should be conducted with appropriate DOC and treatment repeats.  相似文献   

9.
One of the methods to prevent wax precipitation, during petroleum production, transport, and refining, is the use of polymer additives that can reduce the oil pour point. However, no single additive work for all types of crude oil and this relation is not yet well known. In this study, a family of polymers based on poly(ethylene-co-vinyl acetate), containing hydroxyl groups and long pendant hydrocarbon chains (from C6 to C18), were synthesized and characterized by H1 nuclear magnetic resonance and solubility test. Four crude oil samples containing different amounts and size distribution of the wax were used. The additive's action is favored by higher contents of iso + cycloalkanes and lower contents of n-paraffins with larger chain sizes. The presence of the CH3COO group in the copolymers promoted the lowering of the pour point, supported by a low OH concentration and the presence of a long pendant hydrocarbon chain: the best results were obtained with C10 and C12 chain lengths. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48969.  相似文献   

10.
王庆  牛涛涛  李娟  杜秀转 《广州化工》2012,40(19):11-13,50
综述了红外光谱法在植物油脂油定性识别及定量分析中的应用。介绍了红外光谱法分析植物油脂的基本原理。论述了红外光谱法在油脂理化参数的定量分析的研究进展。展望了红外光谱法在油脂检测中的应用前景。提出多种方法联合运用的检测油脂的新思路,为红外光谱法油脂快速分析检以及定性识别分析提供参考。  相似文献   

11.
Viable cells were detected by direct viable count methodology on ozonated anthracite taken from an active dual media rapid sand filter. Also, at least a thousand fold more cells were determined to be viable by direct viable count methodology than by the heterotrophic plate count in raw water which had been exposed to ozone. This suggests that bacterial cells were not killed as quickly by ozone as previously thought, and that the direct viable count may have a place in assessing the effectiveness of killing bacteria by ozone.  相似文献   

12.
The utility of near-infrared transmission spectroscopy (NITS) for the nondestructive prediction of oil content in single maize kernels was explored. Calibration models were developed from spectral information gathered between 850 and 1050 nm. Nuclear magnetic resonance (NMR) spectroscopy was employed as a reference method to determine the actual oil content of samples used for calibration development and testing. Various positionings of the kernels in the light path and calibration math treatments were explored. The best NITS calibration yielded a 1.2% standard error of cross validation, which was over four times the standard error of NMR reproducibility. Although not as accurate as NMR, NITS does have utility in selecting kernels with the highest oil content from a segregating population.  相似文献   

13.
Optothermal window spectroscopy at CO2 laser infrared wavelengths was used to detect the extent of adulteration of extra-virgin olive oil by sunflower and safflower oils. A good linearity between the strength of optothermal signal and the concentration of each adulterating compound was found. Predicted limits of detection presently attainable by this new method are 6 (w/w) and 4.5% (w/w) for extra-virgin olive oil adulterated with safflower oil and sunflower oil, respectively, and were confirmed experimentally; the corresponding relative errors were 0.3 and 0.18%. Interference effects are comparable to those encountered in other spectroscopic methods at the same wavelength.  相似文献   

14.
Ozonation reactions are very important in vegetable oil chemistry since their ozonation products are involved in antimicrobial effect in therapeutical uses for several microbiological etiology diseases. Information on the spectroscopic characterization of the products generated by ozonolysis of sunflower oil is limited. In the present study ozonized sunflower oil with 650 mmol-equiv/kg of peroxide index is chemically characterized. Ozonation of sunflower oil produced ozonides, aldehydes and hydroperoxides which were identified by 1H, 13C and two-dimensional 1H Nuclear Magnetic Resonance (NMR). The virgin sunflower oil and ozonized sunflower oil show very similar 1H NMR spectra except for the resonances at δ = 9.74 and δ = 9.63 ppm that correspond to both triplet from aldehydic protons, δ = 5.6 ppm (olefinic signal from hydroperoxides), and δ = 5.15 ppm (multiplet from ozonides methylic protons). Other resonance assignments are based on the connectivities provided by the proton scalar coupling constants. These are the following: δ = 3.15 ppm (doublet from methylenic group in α position respect to olefinic proton), δ = 2.45 ppm (multiplet from methylenic group allylic to ozonides methynic protons) and δ = 1.62 ppm (multiplet methylenic protons in β position respect to ozonides methynic protons). From the 13C NMR and 1H-13C two- dimensional spectrum of the ozonized sunflower oil, the presence of ozonides was confirmed by the signals δ = 103.43 and δ = 103.49 ppm, respectively. The others new signals found in δ = 42.5 and δ = 42.76 ppm confirm the presence of methylenic carbons from hydroperoxides and ozonides. These results indicate that NMR Spectroscopy can provide valuable information about the amount of reaction compounds of ozonized vegetable oil. From the chemical structural elucidation of ozonated sunflower oils, relevant biochemical and chemical information can be achieved.  相似文献   

15.
Blends of polyaryletherketones (PAEK), such as polyetheretherketones (PEEK) and polyetherketoneketones (PEKK), with polybenzimidazole (PBI) are of commercial interest due to their improved high‐temperature stability and wear properties. The changes of PBI and its PEEK‐ and PEKK‐blends (50 : 50 wt %) after immersing them in liquid H2O and D2O, and exposing them to D2O steam at elevated temperatures and pressures are investigated by multinuclear solid‐state NMR and IR spectroscopy. Macroscopic morphological and chemical changes on the molecular scale, which take place upon high‐temperature steam‐treatment and the extent and reversibility of moisture uptake have been investigated. Interactions and reactions of water, steam, and aqueous solutions of LiCl and ZnBr2 with the functional groups of the polymer components have been studied using D2O in combination with IR, 1H wideline, 2H, 7Li, and 79Br MAS, as well as 13C and 15N CP/MAS NMR spectroscopy. Different locations and types of water and protons in the blends have been described and PBI has been proven to be mainly responsible for water and salt uptake into the blends. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41421.  相似文献   

16.
To verify the feasibility of the determination of the Si?H content (HC) of hydrogen silicone oil (HS‐oil) with Fourier transform near infrared (FT‐NIR) spectroscopy and attenuated total reflectance (ATR)–Fourier transform infrared (FTIR) spectroscopy combined with the partial least squares regression (PLS‐R) model, HS‐oil samples were synthesized from concentrated hydrosilicone oil (HC = 1.4 wt %), octamethylcyclotetrasiloxane, and hexamethyldisiloxane or prepared by the dilution of concentrated hydrosilicone oil with octamethylcyclotetrasiloxane. The FT‐NIR PLS‐R model (8695–4000 cm?1, two principal components) was developed from the FT‐NIR spectral data, and the coefficient of determination for cross‐validation (R2) and the coefficient of determination for external validation (r2) were 0.992 and 0.995, respectively. The ATR–FTIR PLS‐R model (2302–2040 cm?1, one principal component) was developed from the ATR–FTIR spectral data; it produced an R2 of 0.995 and an r2 of 0.996. This study demonstrated that the combination of FT‐NIR and ATR–FTIR spectroscopy with the PLS‐R model were successfully used to determine the HC of the HS‐oil. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40694.  相似文献   

17.
The authenticity of high value edible fats and oils including extra virgin olive oil (EVOO) is an emerging issue, currently. The potential employment of Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics of multivariate calibration and discriminant analysis has been exploited for rapid authentication of EVOO from canola oil (Ca‐O). The optimization of two calibration models of partial least square (PLS) and principle component regression was performed in order to quantify the level of Ca‐O in EVOO. The chemometrics of discriminant analysis (DA) was used for making the classification between pure EVOO and EVOO adulterated with Ca‐O. The individual oils and their blends were scanned on good contact with ZnSe crystals in horizontal attenuated total reflectance, as a sampling technique. The wavenumbers of 3,028–2,985 and 1,200–987 cm?1 were used for quantification and classification of EVOO adulterated with Ca‐O. The results showed that PLS with normal FTIR spectra was well suited for quantitative analysis of Ca‐O with a value of the coefficient of determination (R2) > 0.99. The error, expressed as root mean square error of calibration obtained was relatively low, i.e. 0.108 % (v/v). DA can make the classification between pure EVOO and that adulterated with Ca‐O with one misclassified reported.  相似文献   

18.
Erwinia carotovora subsp. carotovora (Ecc) is a bacterial pathogen that causes decay of vegetables and is found in a wide range of Brassica crops in the Shanghai area, particularly in non-heading Chinese cabbage (NHCC). In this study, aqueous ozone was used as an antimicrobial agent to prevent the growth of Ecc bacterial colonies. Ecc that were treated with aqueous ozone were completely inactivated after the bacteria had been exposed to 0.5 mg/L ozone at 28 °C. Furthermore, a susceptible NHCC cultivar was directly sprayed with different concentrations of dissolved ozonated water as a pesticide substitute. The effects of the treatments on morphology were analyzed, and some treatments were characterized by induction of visible symptoms of senescence. No negative effects were observed after treatment by spraying ozonated water compared with the control at concentrations below 8 mg/L. However, visible damage to leaves was observed after the plants were exposed to 10 mg/L ozonated water via spraying for 15 days during the plant reproductive stage. Additionally, enzyme activities and antioxidant responses gradually increased to a certain degree and then decreased in the untreated and ozonated water-treated plants. These results showed that ozonated water was effective in restraining pathogens and potentially defending against disease in growing NHCC plants within a certain concentration range. These results provide a theoretical basis for preventing disease by applying ozonated water to vegetables as an alternative to pesticides.  相似文献   

19.
FTIR spectroscopic determination of soap in refined vegetable oils   总被引:1,自引:1,他引:0  
A new analytical method was developed for the determination of soap in palm and groundnut oils by FTIR spectroscopy. Soap from 0 to 80 mg/kg oil was produced in situ in the oils by adding sodium hydroxide. The FTIR spectroscopy was with a sodium chloride transmission cell, and the partial least-squares statistical method was used to calibrate a model for each oil. The accuracy of the method was comparable to that of AOCS Method Cc17-95, with coefficients of determination (R 2) of 0.98 and 0.98 for both palm and groundnut oils. The standard errors of calibration were 1.84 and 1.36 for the two oils, respectively. The calibration models were cross-validated, and the R 2 of cross-validation and standard errors of cross validation were computed. The standard deviation of the difference for repeatability of the FTIR method was better than that for the chemical method used for determining soap in palm and groundnut oils. With its speed and ease of data manipulation by computer software, FTIR spectroscopy is a possible alternative to the standard wet chemical methods for rapid (2 min) and accurate routine determination of soap in chemically refined vegetable oils.  相似文献   

20.
The objective of this study was to investigate the potential in vitro biological properties of Oz.Or.Oil 30, a new formulation composed of 30% ozonated sunflower seed oil, which is believed to keep skin smooth and moisturized, supporting repair processes, tissue regeneration and re-epithelialization of wounds. The antibacterial activity, the qualitative and quantitative evaluation of the cytotoxic effect of the formulation on cultures of Vero cells and 3T3 fibroblasts showed that Oz.Or.Oil 30 merits further in vivo study using clinical-laboratory correlations, because it could be suggested as an alternative therapy against bacterial and fungal diseases.  相似文献   

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