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The removal of tetracycline, carbamazepine, and diclofenac sodium from aqueous solutions by passing them through a column with thermally expanded graphite (TEG), which was synthesized from natural graphite, was studied. The method of numerical simulation was used to determine maximally possible breakthrough volumes for the adsorption of each of the substrates on TEG based on the sensitivity of the method of analysis, which was taken equal to 1.5% of the initial substrate concentration in this work. Conditions for the adsorption of the above substances, which are maximally close to the calculated optimum conditions, were found experimentally.

This Letter reports on the new experimental results for second-harmonic generation and sum-frequency generation in LiGaS

The H-theorem is proved for generalized equations of chemical kinetics, and important physical examples of such generalizations are considered: a?discrete model of the quantum kinetic equations (the Uehling-Uhlenbeck equations) and a?quantum Markov process (a?quantum random walk). The time means are shown to coincide with the Boltzmann extremals for these equations and for the Liouville equation. Bibliography: 41 titles.

The derivation of the Vlasov–Maxwell and the Vlasov–Poisson–Poisson equations from Lagrangians of classical electrodynamics is described. The equations of electromagnetohydrodynamics (EMHD) type and electrostatics with gravitation are obtained. We obtain and compare the Lagrange equalities and their generalizations for different types of the Vlasov and EMHD equations. The conveniences of writing the EMHD equations in twice divergent form are discussed. We analyze exact solutions to the Vlasov–Poisson–Poisson equations with the presence of gravitation where we have different types of nonlinear elliptic equations for trajectories of particles with critical mass m2 = e2/G, which has an obvious physical sense, where G denotes the gravitation constant and e is the electron charge. As a consequence we have different behaviors of particles: divergence or collapse of their trajectories.

Thermally expanded graphite, which was obtained from natural graphite as a result of thermal treatment with acids, was used for the removal of tetracycline as a typical antibiotic. The isotherm of adsorption of tetracycline was satisfactorily described by the Langmuir, Temkin, and Freundlich equations. The kinetics of absorption of tetracycline on thermally expanded graphite was studied.

Electrochemical oxidation of tetracycline on a boron-doped diamond electrode in order to develop a method for purification of waste water from contamination by pharmaceutical agents was studied. It was found that under these conditions deep oxidation of tetracycline (TC) down to its full mineralization can take place. Using high resolution mass spectrometry, it was shown that in the first stage of the reaction the oxidation of TC proceeds with the formation of products with higher molecular mass than TC, but with further electrolysis TC transforms into compounds with lower molecular mass, and then into inorganic compounds.

Studies of the electrochemical behavior of hexahydropyrimidine, 1,5-diazabicyclo[3.1.0]hexane, and 1,3-diaminopropane on a gold electrode via cyclic voltammetry allow us to conclude that gold anodes are subject to corrosion in presence these compounds, yielding complexes that migrate into the solutions and discharge on the counter electrode, producing gold metal deposit. 1,5-Diazabicyclo[3.1.0]hexane is found to form complexes with gold that are much more stable that those formed by hexahydropyrimidine and 1,3-diaminopropane.

Single crystals of potassium titanyl phosphate (KTiOPO4, KTP) family (MTiOXO4, where M is K, Rb, or Cs, and X is P or As) with periodical domain structures have emerged as one of the key platforms for enabling nonlinear photonics applications. Potassium titanyl arsenate (KTiOAsO4, KTA) crystals possess nonlinear optical properties outperforming those of KTP. However, domain kinetics in KTA, being the crucial element for periodical poling, lacks comprehensive studies. We present the results of in situ imaging of domain kinetics in KTA with high temporal resolution. The analysis of a set of instantaneous domain structure images (kinetic map) has allowed reliable revealing of the slow and fast domain walls, similar to KTP. The mobility and the threshold fields for the domain walls have been estimated. The main stages of the domain structure evolution have been revealed. The original hatching stage representing the formation of quasiperiodic structure of the narrow stripe domains has been discovered. The relative input of the hatching stage has increased with external field. The obtained qualitative difference in the domain structure evolution, compared with KTP, has been attributed to a six times larger ratio of fast to slow wall mobility in KTA. This fact results in suppression of the undesirable broadening of the stripe domains thus making KTA crystals very attractive for periodical poling.

The electrochemical behavior of hexahydropyrimidine (HHP) on a boron-doped diamond electrode was studied. The obtained data were compared with the results of previous studies on the electrooxidation of HHP on platinum and gold electrodes. It was shown that different products can be obtained from one organic substance using different electrode materials.

The kinetics and mechanism of the deep oxidation of sodium diclofenac on a boron-doped diamond electrode are studied to develop a technique for purifying wastewater from pharmaceutical products. The products of sodium diclofenac electrolysis are analyzed using cyclic voltammetry and nuclear magnetic resonance techniques. It is shown that the toxicity of the drug and products of its electrolysis decreases upon its deep oxidation.

We demonstrate optical parametric oscillators based on the wide band-gap (3.76 eV) LiGaS2 (LGS), pumped by 100-Hz/8-ns and 1-kHz/1-ns laser sources at 1064 nm. Notwithstanding the modest second order nonlinearity of this material singly resonant operation was possible due to the high optical damage resistivity of LGS. Idler pulses near 5.46 μm were generated with an energy of 134 μJ and duration of 5.4 ns in the first case and energy of 1.1 μJ and sub-nanosecond duration in the second case. We present also optical surface damage measurements at 1064 nm using 14-ns pulses.

INTRODUCTIONThe Vlasov–Poisson and Vlasov–Maxwell equations were successfully applied to describe plasma in[1–3]. These equations were reduced to MHDtypeequations by using a hydrodyn amic substitution in [4–8].For the equations of an ideal incompressible fluid,Arnold proved a theorem on the structure of steadystate solutions based on the presence of two commuting vector fields [9]. Kozlov generalized this construction to a contractible fluid [10]. In this paper, we investigate the possibility of such constructions for the Vlasov–Poisson and Vlasov–Maxwell equations.1. THE VLASOV–POISSON EQUATIONSThese equations describe the motion of electrons,electrostatic plasma, or selfgravitating objects, suchas galaxies or galactic clusters. Consider the followingslightly more general case of the Vlasov–Poisson system for gravitational electrostatics [11]:(1)Here, the α denote types of particles

The electrochemical synthesis of 3,12-dimethyl-7,8,15,16-tetraoxadispiro[5.2.5.2]hexadecane (1,2,4,5-tetraoxane) from 1,1-bis-hydroperoxy-4-methylcyclohexane on platinum electrode in a cell with separated and unseparated cathode and anode space in an aprotic solvent is conducted. The kinetics of electrochemical oxidation of 1,1-bis(hydroperoxy)-4-methylcyclohexane is studied. The current yield of the reaction is determined.

The adsorption of a diclofenac sodium medicine from aqueous solutions of different concentrations on expanded graphite, which was obtained as a result of the thermal treatment of graphite with perchloric acid, was studied. The recovery of diclofenac sodium from aqueous solution on expanded graphite was as high as 98–99%.

This dissertation argues that the richness and distinctiveness of modern Yiddish travel literature—with its emphasis on arriving rather than departing—reflects the complexity of such East European Jewish notions as home, homelessness, and wandering. It examines the ways in which the experience of travel affected the search for identity, home, and belonging by Yiddish writers from the first secularized and westernized generation of East European Jews. Yiddish travelogues written in the first four decades of the twentieth century show a curious trend with respect to the search for identity and the destinations that are their subject. These destinations fall into two categories: those with specific Jewish connotations and those without. For writers addressing the latter destination category, even though motivated by the search for a Jewish identity, locales beyond the Jewish map engender the greatest sense of empowerment. Even when their ostensible motivations and emphases are diametrically opposed, they arrive at the same conclusion, that Jews belong simultaneously nowhere and everywhere. Peretz Hirschbein and Melech Ravitch are exemplary illustrations of this tendency: the former laments the countless roads on which Jews have traveled and many borders that separate them; he longs for universal brotherhood and closeness to nature, and as such rejects the diversity of the Jewish experience; the latter, on the contrary, celebrates diversity. How can we explain this trend? It is born of the contradictory set of ideological and artistic aims and interests of a generation that rejected the traditional beliefs and lifestyle of their parents, and that aimed to create a body of modern literature in Yiddish that would equal major European literatures, and that internalized a number of European cultural (primarily literary) tropes. Moreover, this literature was the product of a generation of writers who yearned for an organic connection to Jewish past, present, and future and at the same time saw problems with every existing ideology. The Introduction situates the study within the context of Jewish cultural and literary history and addresses questions of scope and methodology. Chapter 1 analyzes Yiddish travel writers’ fascination with exotic destinations lacking specifically Jewish connotations and its role in these writers’ struggles to define their cultural identity. Chapter 2 analyzes the work of Peretz Hirschbein and argues that his longing for universal brotherhood and closeness to nature reflected both a reluctance to celebrate the diversity of the Jewish experience and an impulse to embrace its global proportions. Chapter 3 focuses on the life and work of Melech Ravitch and contrasts his passion for diversity with the opposite approach of Peretz Hirschbein. Chapter 4 explores Yiddish writers’ travel to Mandate Palestine and to Soviet Russia and focuses on the parallels between travelogues about these two politically charged destinations. Chapter 5 examines the development of Yiddish travel literature after World War II, focusing both on works that describe travel back to Eastern Europe and are dominated by the themes of mourning and preservation, and on later works, filled with the urge to affirm a worldwide Jewish presence. The Conclusion recapitulates the dissertation’s main points and stresses the uniqueness of the Yiddish travelogue and its importance in Jewish studies and beyond.

LiGaSe2 (LGSe) and LiInSe2 (LISe) are wide band-gap nonlinear crystals transparent in the mid-IR spectral range. LiGa0.5In0.5Se2 (LGISe) is a new mixed crystal, a solid solution in the system LGSe–LISe, which exhibits the same orthorhombic structure (mm2) as the parent compounds in the same time being more technological with regard to the growth process. In comparison with LGSe and LISe its homogeneity range is broader in the phase diagram. About 10% of the Li ions in LGISe occupy octahedral positions (octapores) with coordination number of 3. The band-gap of LGISe is estimated to be 2.94 eV at room temperature and 3.04 eV at 80 K. The transparency at the 0-level extends from 0.47 to 13 µm. LGISe crystals exhibit luminescence in broad bands centered near 1.7 and 1.25 eV which is excited most effectively by band-to-band transition. From the measured principal refractive indices and the fitted Sellmeier equations second-harmonic generation from 1.75 to 11.8 μm (fundamental wavelength) is predicted. The nonlinear coefficients of LGISe have values between those of LGSe and LISe. 6LGISe crystals are considered promising also for detection of thermal neutrons.

The regularities of AlkNHBr consumption in the reaction of formation of 1,2-dialkyldiaziridines in aqueous media were studied for the first time by UV spectrometry. The rate constants of particular steps of the reaction were estimated starting from the possibility of formation of the precursor of 1,2-dialkyldiaziridine, N-halogenaminal, due to the amination of the intermediate iminium cation along with the parallel halogenation of the intermediate gem-diamine. The quantum chemical calculations (DFT, B3LYP, 6–31++G(d,p) and 3–21G basis sets) were performed for the spatial and electronic structures of the compounds and indices of the local reactivity and global electrophilicity of the key intermediates of the reactions. The results of the calculations allowed us to explain the retardation of the reaction when using EtNHBr instead of MeNHBr.

We describe the derivation of the Vlasov-Maxwell equations from the Lagrangian of classical electrodynamics, from which magnetohydrodynamic-type equations are in turn derived. We consider both the relativistic and nonrelativistic cases: with zero temperature as the exact consequence of the Vlasov-Maxwell equations and with nonzero temperature as a zeroth-order approximation of the Maxwell-Chapman-Enskog method. We obtain the Lagrangian identities and their generalizations for these cases and compare them.

Time averages are proved to coincide with Boltzmann extremals for Markov chains, discrete Liouville equations, and their generalizations. A variational principle is proposed for finding stationary solutions in these cases.

A four-point probe method was used to study, as the layers were removed consecutively, the concentration distribution profiles of free electrons in high-resistivity p-Si with implanted P+ and Na+ ions. Anodic oxidation was used to remove layers at a depth of less than 1 μm, and polishing at larger depths. It was shown that the efficiency of diffusion doping of silicon with sodium is determined, to a large extent, by the ratio between the energies of P+ and Na+ ions. If the conditions are optimal, the efficiency of doping by simultaneous implantation of sodium and phosphorus ions is better (by a factor of 2.5 on the average) than that of doping with Na+ ions only.

The possibility is shown of electrochemical synthesis of 3,12-dimethyl-7,8,15,16-tetraoxadispiro[5.2.5.2]hexadecane that belong to the class of 1,2,4,5-tetraoxanes by oxidation of 1,1-dihydroperoxy-4-methylcyclohexane using a Pt anode.

Electrochemical degradation of diclofenac in aqueous solutions was studied using a thin-film boron-doped diamond electrode deposited onto a niobium plate. The process was monitored by means of UV spectroscopy and elemental analysis.

Electroreduction of an equilibrium menthone-isomenthone mixture at a controlled potential in a diaphragm cell on various cathodes was studied. The influence exerted by the nature of a solvent and of an electrode, electrode material, and various additives on the reduction stereoselectivity of ketones was examined. Conditions for a predominant formation of the most stable of the four isomeric alcohols being formed, menthol, were found.