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1.
The objective of this investigation was to assess the quantity of collagen fibers with different dosages of recombinant human bone morphogenetic protein, type 2 (rhBMP-2) associated with two different carriers, monoolein and poloxamer gels, in critical bone defects created in the calvaria of Wistar rats. Forty male adult Wistar rats were divided into eight groups of 5 animals each—group I: critical bone defect with application of 1 μg of rhBMP-2 combined with monoolein gel; group II: 3 μg of rhBMP-2 combined with monoolein gel; group III: 7 μg of rhBMP-2 combined with monoolein gel; group IV: 1 μg of rhBMP-2 combined with poloxamer gel; group V: 3 μg of rhBMP-2 combined with poloxamer gel; group VI: 7 μg of rhBMP-2 combined with poloxamer gel; group VII: monoolein gel only and group VIII: poloxamer gel only. A critical-sized defect of 6 mm diameter was produced in the left parietal bone using a surgical round bur and a high-speed micromotor. The bone defects were filled according to the group that animals belonged and after two weeks the rats were perfused and their calvarial bones were removed for histological processing, and collagen fibers quantification. Differences among the eight groups were statistically analyzed by Anova and Bonferroni test (p < 0.05). The results did not show statistical difference between the groups, in exception, between the comparisons II and III. According to the experimental methodology used in this research, it was observed, in a general way, a qualitative inverse relationship between collagen fibers presence and rhBMP-2 quantity inserted in the critical bone defect, associated or not to a material carrier.  相似文献   

2.
This study aimed at verifying the effects of phonophoresis associated with Arnica montana on the acute phase of an inflammatory muscle lesion. Forty Wistar male rats (300 ± 50 g), of which the Tibialis Anterior muscle was surgically lesioned, were divided into four groups (n = 10 each): control group received no treatment; the ultrasound group (US) was treated in pulsed mode with 1-MHz frequency, 0.5 W/cm2 intensity (spatial and temporal average – SATA), duty cycle of 1:2 (2 ms on, 4 ms off, 50%), time of application 3 min per session, one session per day, for 3 days; the phonophoresis or ultrasound plus arnica (US+A) group was treated with arnica with the same US parameters plus arnica gel; and the arnica group (A) was submitted to massage with arnica gel, also for 3 min, once a day, for 3 days. Treatment started 24 h after the surgical lesion. On the 4th day after lesion creation, animals were sacrificed and sections of the lesioned, inflamed muscle were removed for quantitative (mononuclear and polymorphonuclear cell count) and qualitative histological analysis. Collected data from the 4 groups were statistically analyzed and the significance level set at p < 0.05. Results show higher mononuclear cell density in all three treated groups with no significant difference between them, but values were significantly different (p < 0.0001) when compared to control group’s. As to polymorphonuclear cell density, significant differences were found between control group (p = 0.0134) and US, US+A and A groups; the arnica group presented lesser density of polymorphonuclear cells when compared (p = 0.0134) to the other groups. No significant difference was found between US and US+A groups. While the massage with arnica gel proved to be an effective anti-inflammatory on acute muscle lesion in topic use, these results point to ineffectiveness of Arnica montana phonophoresis, US having seemingly checked or minimized its anti-inflammatory effect.  相似文献   

3.
High intensity ultrasonic (HUS, 20 k Hz, 400 W) pre-treatments of soybean protein isolate (SPI) improved the water holding capacity (WHC), gel strength and gel firmness (final elastic moduli) of glucono-δ-lactone induced SPI gels (GISG). Sonication time (0, 5, 20, and 40 min) had a significant effect on the above three properties. 20 min HUS-GISG had the highest WHC (95.53 ± 0.25%), gel strength (60.90 ± 2.87 g) and gel firmness (96340 Pa), compared with other samples. Moreover, SH groups and non-covalent interactions of GISG also changed after HUS pre-treatments. The HUS GISG had denser and more uniform microstructures than the untreated GISG. Rheological investments showed that the cooling step (reduce the temperature from 95 to 25 °C at a speed of 2 °C/min) was more important for the HUS GISG network formation while the heat preservation step (keep temperature at 95 for 20 min) was more important for the untreated GISG. HUS reduced the particle size of SPI and Pearson correlation test showed that the particle size of SPI dispersions was negatively correlated with WHC, gel strength and gel firmness.  相似文献   

4.
Strontium ranelate has been used to prevent bone loss and stimulate bone regeneration. Although strontium may integrate into the bone crystal lattice, the chemical and structural modifications of the bone when strontium interacts with the mineral phase are not completely understood. The objective of this study was to evaluate apatite from the mandibles of rats treated with strontium ranelate in the drinking water and compare its characteristics with those from untreated rats and synthetic apatites with and without strontium. Electron energy loss near edge structures from phosphorus, carbon, calcium and strontium were obtained by electron energy loss spectroscopy in a transmission electron microscope. The strontium signal was detected in the biological and synthetic samples containing strontium. The relative quantification of carbon by analyzing the CK edge at an energy loss of ΔE = 284 eV showed an increase in the number of carbonate groups in the bone mineral of treated rats. A synthetic strontium-containing sample used as control did not exhibit a carbon signal. This study showed physicochemical modifications in the bone mineral at the nanoscale caused by the systemic administration of strontium ranelate.  相似文献   

5.
Magnesium (Mg) and Strontium (Sr) doped Calcium fluoride nanocrystals were synthesized by co-precipitation method. The cubic structure of the samples was confirmed by Powder X-ray diffraction. The average crystallite size of Mg doped samples was found to be ~ 25 nm whereas in Sr doped one it was ~ 35 nm. The morphological features revealed that the nanocrystals were agglomerated, crispy and porous. The as-prepared samples showed the presence of hydroxyl groups. The optical absorption spectrum of as-prepared Mg doped samples showed a strong absorption band peaked at ~ 233 nm whereas the Sr doped one showed a prominent absorption peak at 248 nm. A strong PL emission was observed at ~ 300 nm in Mg doped samples. However, the Sr doped samples showed two prominent emissions at ~ 345 and 615 nm.  相似文献   

6.
Mesoporous silica (MPS) materials with different pore diameters were synthesized by a sol–gel method where organic templates such as cationic surfactant (cetyltrimethylammonium bromide) and triblock co-polymer of (poly(ethylene glycol)–poly(propylene glycol)–poly(ethylene glycol) (Pluronic P123, EO20PO70EO20)), were used. MPS surface was organo-functionalized using a silane coupling reagent (ethyl-, phenyl-, or 3-mercaptpropyltriethoxysilane). Dual-enzyme, cholesterol esterase (10.0 nm × 5.4 nm × 11.0 nm) and cholesterol oxidase (6.8 nm × 8.5 nm × 8.8 nm), was immobilized on MPS materials by physical adsorption. Amount of dual-enzyme immobilized on all MPS materials, having a different pore size (2.7, 6.4, 12.4, 14.7, and 22.6 nm), and organo-functionalized MPS was similar (CE: 1.5 mg/mg silica and CO: 0.01 mg/mg silica). High activity of dual-enzyme was obtained by adjacently immobilizing on MPS materials. Its activity on MPS-2 (pore diameter: 6.4 nm) or MPS-5 (pore diameter: 22.6 nm) showed approximately 60% of native activity. Moreover, dual-enzyme immobilized on MPS with highly hydrophobic organo-functional groups (phenyl- or mercaptopropyl-group) exhibited higher activity than that on no-substituted MPS. Relative activity of dual-enzyme immobilized on organo-functionalized MPS-2 increased from 58% to 93%, under the optimum conditions.  相似文献   

7.
The surface of ultra high molecular weight polyethylene (UHMWPE) was exposed to γ-ray for improving bonding strength to polymethylmethacrylate (PMMA) bone cement. Two types of irradiation methods, pre-irradiation and syn-irradiation, were engaged in this study. The intensity of irradiation was 5–30 kGy for pre-irradiation, and 1–3 kGy for syn-irradiation. The grafting process was performed in a glass ampule filled with methanol, MMA monomer (60 v%), FeSO4 · 7H2O (1.5 × 10−4 M) and H2SO4 (0.1 M). The graft rate of each specimen was measured with time variation. The grafting effect of the acrylates on to the UHMWPE surface was investigated by mechanical test for bonding strength. Pre-irradiation method showed thinner coverage PMMA graft on the surface of the UHMWPE and higher bonding strength than syn-irradiation method. The interfacial bonding strength between UHMWPE and PMMA bone cement was considerably improved by γ-ray irradiation method. For medical application, the pre-irradiation method might be recommended, because the PMMA could be grafted as optimized thickness to the UHMWPE surface.  相似文献   

8.
《Ultrasonics sonochemistry》2014,21(4):1549-1556
This paper reports on the sonochemical synthesis of zinc oxide (ZnO) nanophosphors (NPr) at different ultrasonication times (5 min, 30 min, 1 h, 5 h, 10 h and 15 h) for near white light emission applications. X-ray photoelectron spectroscopy indicated that the O1s peak consists of two components. These were O1 (ZnO) and O2 (deficient oxygen; OH groups) centred at 529.7 ± 0.3 eV and 531.1 ± 0.3 eV, respectively. All samples showed UV and defect level emission (DLE). The DLE enhancement was due to the increase in oxygen related defects such as oxygen vacancies/interstitials. Due to the combination of near UV and DLE near white light emission in ZnO NPr was obtained. The emission could be tuned with different ultrasonic times. It was found that the ultrasonication time influenced the growth mechanism and luminescence properties of the ZnO NPr.  相似文献   

9.
Control of heat dissipation and transmission to the peri-implant area during intra-oral welding is very important to limit potential damage to the surrounding tissue. The aim of this in vitro study was to assess, by means of thermal infrared imaging, the tissue temperature peaks associated with the thermal propagation pathway through the implants, the abutments and the walls of the slot of the scaffold, generated during the welding process, in three different implant systems. An in vitro polyurethane mandible model was prepared with a 7.0 mm v-shape slot. Effects on the maximum temperature by a single welding procedure were studied using different power supplies and abutments. A total of 36 welding procedures were tested on three different implant systems. The lowest peak temperature along the walls of the 7.0 mm v-shaped groove (31.6 ± 2 °C) was assessed in the specimens irrigated with sterile saline solution. The highest peak temperature (42.8 ± 2 °C) was assessed in the samples with a contemporaneous power overflow and premature pincers removal. The results of our study suggest that the procedures used until now appear to be effective to avoid thermal bone injuries. The peak tissue temperature of the in vitro model did not surpass the threshold limits above which tissue injury could occur.  相似文献   

10.
Spinal myeloma and metastatic cancer cause similar symptoms and show similar imaging presentations, thus making them difficult to differentiate. In this study, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was performed to differentiate between 9 myelomas and 22 metastatic cancers that present as focal lesions in the spine. The characteristic DCE parameters, including the peak signal enhancement percentage (SE%), the steepest wash-in SE% during the ascending phase and the wash-out SE%, were calculated by normalizing to the precontrast signal intensity. The two-compartmental pharmacokinetic model was used to obtain Ktrans and kep. All nine myelomas showed the wash-out DCE pattern. Of the 22 metastatic cancers, 12 showed wash-out, 7 showed plateau, and 3 showed persistent enhancing patterns. The fraction of cases that showed the wash-out pattern was significantly higher in the myeloma group than the metastatic cancer group (9/9 = 100% vs. 12/22 = 55%, P = .03). Compared to the metastatic cancer group, the myeloma group had a higher peak SE% (226% ± 72% vs. 165% ± 60%, P = .044), a higher steepest wash-in SE% (169% ± 51% vs. 111% ± 41%, P = .01), a higher Ktrans (0.114 ± 0.036 vs. 0.077 ± 0.028 1/min, P = .016) and a higher kep (0.88 ± 0.26 vs. 0.49 ± 0.23 1/min, P = .002). The receiver operating characteristic analysis to differentiate between these two groups showed that the area under the curve was 0.798 for Ktrans, 0.864 for kep and 0.919 for combined Ktrans and kep. These results show that DCE-MRI may provide additional information for making differential diagnosis to aid in choosing the optimal subsequent procedures or treatments for spinal lesions.  相似文献   

11.
Silver (Ag) nanorods with the average length of 280 nm and diameters of around 25 nm were synthesized by a simple reduction process of silver nitrate in the presence of polyvinyl alcohol (PVA) and investigated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission-electron microscopy (TEM) and UV–vis spectrum. It was found out that both temperature and reaction time are the important factors in determining the morphology and aspect ratios of nanorods. TEM images showed the prepared Ag nanorods have a face centered shape (fcc) with fivefold symmetry consisting of multiply twinned face centered cubes as revealed in the cross-section observations. The fivefold axis, i.e. the growth direction, normally goes along the (1 1 1) zone axis direction of the basic fcc Ag-structure. Preferred crystallographic orientation along the (1 1 1), (2 0 0) or (2 2 0) crystallographic planes and the crystallite size of the Ag nanorods are briefly analyzed.  相似文献   

12.
In this study, the effects of ultrasound with different ultrasonic frequencies on the properties of sodium alginate (ALG) were investigated, which were characterized by the means of the multi-angle laser light scattering photometer analysis (GPC-MALLS), rheological analysis, circular dichroism (CD) spectrometer and scanning electron microscope (SEM). It showed that the molecular weight (Mw) and molecular number (Mn) of the untreated ALG was 1.927 × 105 g/mol and 4.852 × 104 g/mol, respectively. The Mw of the ultrasound treated ALG was gradually increased from 3.50 × 104 g/mol to 7.34 × 104 g/mol while the Mn of ALG was increased and then decreased with the increase of the ultrasonic frequency. The maximum value of Mn was 9.988 × 104 g/mol when the ALG was treated by ultrasound at 40 kHz. It indicated that ultrasound could induce ALG degradation and rearrangement. The number of the large molecules and small molecules of ALG was changed by ultrasound. The value of dn/dc suggested that the ultrasound could enhance the stability of ALG. Furthermore, it was found that ALG treated by ultrasound at 50 kHz tended to be closer to a Newtonian behavior, while the untreated and treated ALG solutions exhibited pseudoplastic behaviours. Moreover, CD spectra demonstrated that ultrasound could be used to improve the strength of the gel by changing the ratio of M/G, which showed that the minimum ratio of M/G of ALG treated at 135 kHz was 1.34. The gel-forming capacity of ALG was correlated with the content of G-blocks. It suggested that ALG treated by ultrasound at 135 kHz was stiffer in the process of forming gels. The morphology results indicated that ultrasound treatment of ALG at 135 kHz increased its hydrophobic interaction and interfacial activity. This study is important to explore the effect of ultrasound on ALG in improving the physical properties of ALG as food additives, enzyme and drug carriers.  相似文献   

13.
《Ultrasonics》2013,53(1):232-238
We aimed to investigate the role of the ABCG2 transporter in the efficacy of sonodynamic therapy (SDT) with Photofrin in the glioma stem-like cells (GSCs) isolated and cultured from U251 glioma cells. Immunocytochemistry and flow cytometry analyses showed that ABCG2 was overexpressed in GSCs, and the percentage of ABCG2-positive GSCs was approximately 100%. The effect of ABCG2 on Photofrin extrusion in the absence or presence of a specific inhibitor of ABCG2 (fumitremorgin C; FTC) was investigated by determining the intracellular concentration of Photofrin in GSCs incubated with 20 μg/ml Photofrin. Extrusion of Photofrin by ABCG2 was inhibited by 10 μM FTC, which significantly increased the intracellular Photofrin concentration (p < 0.05) from 0.32 ± 0.11 μg/106 cells to 0.89 ± 0.13 μg/106 cells. MTT and TUNEL assays showed that the antitumor effect of SDT (incubation of GSCs with 20 μg/ml Photofrin for 6 h in the dark and ultrasonic activation at 1.0 MHz and 0.5 W/cm2 for 2 min) was significantly improved by FTC pretreatment (p < 0.05). Moreover, incubation of GSCs with FTC significantly increased the relative production of ROS in response to SDT. The overexpression of ABCG2 in GSCs results in efflux of Photofrin, indicating that the antitumor effect of SDT with Photofrin may be reduced in GSCs overexpressing ABCG2. However, since FTC improves the efficacy of SDT in GSCs by inhibiting ABCG2-mediated efflux of Photofrin, FTC may be useful in SDT treatment of ABCG2-expressing cancer cells.  相似文献   

14.
Low level laser therapy (LLLT) is known for its positive results but studies on the biological and biomodulator characteristics of the effects produced in the skeletal muscle are still lacking. In this study the effects of two laser dosages, 5 or 10 J/cm2, on the lesioned tibial muscle were compared. Gerbils previously lesioned by 100 g load impact were divided into three groups: GI (n = 5) controls, lesion non-irradiated; GII (n = 5), lesion irradiated with 5 J/cm2 and GIII (n = 5), lesion irradiated with 10 J/cm2, and treated for 7 consecutive days with a laser He–Ne (λ = 633 nm). After intracardiac perfusion, the muscles were dissected and reduced to small fragments, post-fixed in 1% osmium tetroxide, dehydrated in increasing alcohol concentrations, treated with propylene oxide and embedded in Spurr resin at 60 °C. Ultrafine cuts examined on a transmission electron microscope (Jeol 1010) revealed in the control GI group a large number of altered muscle fibers with degenerating mitochondria, intercellular substance containing degenerating cell fragments and budding blood capillaries with underdeveloped endothelial cells. However, groups GII and GIII showed muscle fibers with few altered myofibrils, regularly contoured mitochondria, ample intermembrane spaces and dilated mitochondrial crests. The clean intercellular substance showed numerous collagen fibers and capillaries with multiple abluminal processes, intraluminal protrusions and several pinocytic vesicles in endothelial cells. It was concluded that laser dosages of 5 or 10 J/cm2 delivered by laser He–Ne (λ = 633 nm) during 7 consecutive days increase mitochondrial activity in muscular fibers, activate fibroblasts and macrophages and stimulate angiogenesis, thus suggesting effectivity of laser therapy under these experimental conditions.  相似文献   

15.
The inertial cavitation activity depends on the sonication parameters. The purpose of this work is development of dual frequency inertial cavitation meter for therapeutic applications of ultrasound waves. In this study, the chemical effects of sonication parameters in dual frequency sonication (40 kHz and 1 MHz) were investigated in the progressive wave mode using iodide dosimetry. For this purpose, efficacy of different exposure parameters such as intensity, sonication duration, sonication mode, duty factor and net ultrasound energy on the inertial cavitation activity have been studied. To quantify cavitational effects, the KI dosimeter solution was sonicated and its absorbance at a wavelength of 350 nm was measured. The absorbance values in continuous sonication mode was significantly higher than the absorbance corresponding to the pulsed mode having duty factors of 20–80% (p < 0.05). Among different combination modes (1 MHz100% + 40 kHz100%, 1 MHz100% + 40 kHz80%, 1 MHz80% + 40 kHz100%, 1 MHz80% + 40 kHz80%), the continuous mode for dual frequency sonication is more effective than other combinations (p < 0.05). The absorbance for this combined dual frequency mode was about 1.8 times higher than that obtained from the algebraic summation of single frequency sonications. It is believed that the optimization of dual frequency sonication parameters at low-level intensity (<3 W/cm2) by optically assisted cavitation event sensor can be useful for ultrasonic treatments.  相似文献   

16.
《Current Applied Physics》2009,9(5):1093-1096
Dimethyl methylphosphonate (DMMP), a chemical simulant of the nerve gas GB, was decontaminated with a nonthermal atmospheric pressure plasma. The decontamination efficiency was measured qualitatively by means of Fourier transform spectroscopy and quantitatively by means of gas chromatography. With helium gas only, 10 g/m2 of DMMP on an aluminum surface was 99.9% decontaminated in 2 min, furthermore, with the addition of 5% of oxygen gas, it was 99.99% decontaminated in 10 min. Given the low input power (<100 W) and temperature (<75 °C), this plasma is eligible for nondestructive decontamination of almost all material surfaces.  相似文献   

17.
PurposeQuantification of myocardial oxygenation (MO) in heart failure (HF) has been less than satisfactory. This has necessitated the use of invasive techniques to measure MO directly or to determine the oxygen demand during exercise using the cardiopulmonary exercise (CPX) test. We propose a new quantification method for MO using blood-oxygen-level-dependent (BOLD) myocardial T2* magnetic resonance imaging (M-T2* MRI), and investigate its correlation with CPX results.MethodsThirty patients with refractory HF who underwent cardiac MRI and CPX test for heart transplantation, and 24 healthy, age-matched volunteers as controls were enrolled. M-T2* imaging was performed using a 3-Tesla and multi-echo gradient-echo sequence. M-T2* was calculated by fitting the signal intensity data for the mid-left ventricular septum to a decay curve. M-T2* was measured under room-air (T2*-air) and after inhalation of oxygen for 10 min at a flow rate of 10 L/min (T2*-oxy). MO was defined as the difference between the two values (ΔT2*). Changes in M-T2* at the two conditions and ΔT2* between the two groups were compared. Correlation between ΔT2* and CPX results was analyzed using the Pearson coefficient.ResultsT2*-oxy was significantly greater than T2*-air in patients with HF (29.9 ± 7.3 ms vs. 26.7 ± 6.0 ms, p < 0.001), whereas no such difference was observed in controls (25.5 ± 4.0 ms vs. 25.4 ± 4.4 ms). ΔT2* was significantly greater for patients with HF than for controls (3.2 ± 4.5 ms vs. -0.1 ± 1.3 ms, p < 0.001). A significant correlation between ΔT2* and CPX results (peak VO2, r =  0.46, p < 0.05; O2 pulse, r =  0.54, p < 0.005) was observed.ConclusionΔT2* is increased T2*-oxy is greater in patients with HF, and is correlated with oxygen metabolism during exercise as measured by the CPX test. Hence, ΔT2* can be used as a surrogate marker of MO instead of CPX test.  相似文献   

18.
Results of indentation-induced hardness testing studies on potassium zinc chloride crystals doped with Li+ ions, leading to an understanding of their mechanical behaviour, are presented. The Vickers hardness of these crystals for (1 0 0), (0 1 0) and (0 0 1) planes in the load range 20–160 g were studied. Load-independent values of hardness are estimated for the three crystallographic planes by applying Hays-Kendall’s and Li-Bradt models. The results showed that: (1) for the three crystallographic planes the load-independent hardness obtained by Li-Bradt model is higher than that predicted by Hays-Kendall’s, approach; (2) the load independent hardness of the (0 0 1) plane is higher than that of both (1 0 0) and (0 1 0) planes, (3) the values of load-independent hardness depend on Li+ concentrations in the K2ZnCl4 crystals, (4) the variations of crack length and crack morphology are described for studied crystal planes.  相似文献   

19.
Background and purposeTo assess the sensitivity of non-localized, whole-head 1H-MRS to an individual's serial changes in total-brain NAA, Glx, Cr and Cho concentrations — metabolite metrics often used as surrogate markers in neurological pathologies.Materials and methodsIn this prospective study, four back-to-back (single imaging session) and three serial (successive sessions) non-localizing, ~3 min 1H-MRS (TE/TR/TI = 5/104/940 ms) scans were performed on 18 healthy young volunteers: 9 women, 9 men: 29.9 ± 7.6 [mean ± standard deviation (SD)] years old. These were analyzed by calculating a within-subject coefficient of variation (CV = SD/mean) to assess intra- and inter-scan repeatability and prediction intervals. This study was Health Insurance Portability and Accountability Act compliant. All subjects gave institutional review board-approved written, informed consent.ResultsThe intra-scan CVs for the NAA, Glx, Cr and Cho were: 3.9 ± 1.8%, 7.3 ± 4.6%, 4.0 ± 3.4% and 2.5 ± 1.6%, and the corresponding inter-scan (longitudinal) values were: 7.0 ± 3.1%, 10.6 ± 5.6%, 7.6 ± 3.5% and 7.0 ± 3.9%. This method is shown to have 80% power to detect changes of 14%, 27%, 26% and 19% between two serial measurements in a given individual.ConclusionsSubject to the assumption that in neurological disorders NAA, Glx, Cr and Cho changes represent brain-only pathology and not muscles, bone marrow, adipose tissue or epithelial cells, this approach enables us to quantify them, thereby adding specificity to the assessment of the total disease load. This will facilitate monitoring diffuse pathologies with faster measurement, more extensive (~90% of the brain) spatial coverage and sensitivity than localized 1H-MRS.  相似文献   

20.
When ultrasound (US) was exposed to aqueous coumarin solution in air atmosphere, the UV–visible and fluorescence spectra of the probe were measured at different US exposure times. The US exposure was carried out at 43 kHz and 500 kHz with different out-put power. It was found that the 500 kHz US produced umbelliferone fluorescence, while the 43 kHz US had no fluorescence. In addition, the coumarin absorbance at 270 nm maximum was decreased with in cases of the US exposure time. In contrary, the fluorescent intensity of umbelliferone at 460 nm increased with increasing of US exposure time. This exhibited that the coumarin probe was converted to umbelliferone by the US exposure, when the 500 kHz US was operated. This was facted that the coumarin framework was caused with addition of OH groups which was generated by the 500 kHz US. Therefore, the umbelliferone fluorescent became a probe to estimate OH radical in US medium. Furthermore, the chemo-fluorometry showed that the emission maximum of the formed umbelliferone could probe the bulk pHs in the US aqueous medium.  相似文献   

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