The adsorption isotherms of nickel ions from aqueous solutions on bentonite, a natural argillaceous material, previously prepared using ultrahigh-frequency electromagnetic waves ("microwaves") were researched in the article. The phase composition of the sorbent was studied by applying the X-ray powder method. Bentonite sample being pre-wetted and irradiated by microwaves shows 2.7 times better sorption properties than the untreated (native) sample, which was shown on the example of the adsorption process of nickel ions from model solutions in static conditions. The sorption parameters prepared by using the "microwaved" and the native samples of bentonite were calculated according to the Langmuir adsorption equations. The barrier density of nickel in the irradiated sorbent is 16.4 mg/g (0.28 mmol/g), whereas for native bentonite the value of the analogous parameter is 6.0 mg/g (0.10 mmol/g). The reason for such an increase in sorption properties may be the change in the crystalline structure and distribution of micropores on the surface of the sorbent under the action of "microwaves" in the aqueous medium. The determinants in the pre-preparation of sorbent by "microwaves" are the ultimate power and time of irradiation.
The physicochemical parameters of the process of sorption water purification from compounds of Nickelwith clay sorbent in static conditions are studied. The absorption isotherm of ions of this metal from concentratedaqueous solutions on samples of bentonite using ultrahigh-frequency irradiation (microwave) is analyzed. Mostcorrectly, it is described by the linear equation of Langmuir. It is shown that irradiation of this sorbent bymicrowaves in the process of nickel ion sorting almost 2 times increases the value of the marginal sorptioncapacity for this metal (in comparison with the method of "stimulation" - preliminary washing of bentonite withpure water under the action of microwaves). The results of the study of spent bentonite by scanning electronmicroscopy, energy dispersion and X-ray diffraction analysis indicate that the metal under action of themicrowave is deposited on the surface of the bentonite not only in the form of an adsorbed monolayer of ions, butalso in the form of a separate crystalline phase, nickel silicate. Changes in the acidity of the medium duringsorption purification under the action of microwave are observed: from pH ≈ 5.7 ... 6.5 (before exposure) to pH ≈6.7 ... 7.1 (after irradiation). Confirmed assumption about that under the action of microwaves in the aqueousmedium there is a partial destruction of the silicate framework of clay sorbents with the release of silicon ionsSiO32-. These ions undergo hydrolysis, as a result of which the pH of the solution increases. Also, the directdiscontinuity of the Si-O bonds in the near-surface groups ≡Si-OH is not excluded, which leads to an increase inthe number of "free" hydroxyl groups.
The central oscillator for the inner clock is the suprachiasmatic nuclei of the hypothalamus. Furthermore, many peripheral oscillators are present in tissues such as skin. Human derived fibroblasts provide an advantageous model to study circadian rhythmicity as well as the influence of pharmacological drugs on circadian gene expression. Importantly, the synchronization of the circadian system of fibroblasts can be done by different methods. The review presents an overview of the current knowledge of different synchronization methods mostly used in mice or rat fibroblasts. Furthermore, the review sums up and discusses the role of norepinephrine as a possible synchronizer agent.
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