UV Ones Research Articles

Environmentally sustainable computationally spectrophotometric resolution strategy for analysis single-tablet regimens of antihypertension with overlapped spectra

Single tablet regimens (STRs) for hypertension suppression improve patient satisfaction, quality of life, medication and adherence compared to multi-tablet regimens (MTRs). Development of simple cost effective and at the same time green an ecofriendly method for analysis and resolution of multicomponent and complex mixtures is an increasingly important issue in the field of pharmaceutical industry in general and analytical chemistry in specific. Thus, the presented research deals with two main goals, the first one is concerned with developing and applying a fully validated resolution plan using numerical data of signals on manipulated spectra for successive extraction of parent spectra of drugs in single-tablet Regimens (STRs) used in antihypertensive treatment. The STRs contains three drugs with deconvoluted spectra, Atenolol (ATL), Amiloride (AMD) and Chlortalidone (CLN). The resolution plan encompasses two simple and affordable spectrophotometric methods employing resolving spectra either normalized spectrum (NS) or factorized spectrum (FS) which acts as a master key for unlocking the overlapped spectra of ternary mixture with no need for any preliminary physical separation, sample pretreatment or pH adjustment. These two main methods namely, dual amplitude difference (DAD) and derivative ratio transformation (DDT). The presented approaches required a simple spectrophotometer with its built-in program using primitive mathematical operations to restore the parent spectrum for individually drug cited in the mixture understudy. The proposed methods validity was checked and evaluated through the ICH guidelines and displayed linearity within concentration range 4.0-40.0μg/mL for ATL, 3.0-20.0μg/mL for both AMD and CLN. While the specificity evaluation was performed via assaying the three drugs accurately and precisely in their synthetic mixtures and in their STRs. Generally, these methods could be recruited for the fast and effective analysis and determination of the purity index for AMD, CLN and ATL in bulk materials and available market formulation, Teklo ® tablets.The second main goal of the research was the evaluation of the methods greenness and whiteness where the applied UV-methods and the reported HPLC one had significantly different greenness scores when compared using three metrics: the Green Certificate Classification (GCC), the Complex Green Analytical Procedure Index (Complex-GAPI), and the Analytical Greenness metric approach (AGREE).Also, the whiteness scores, which reflected the degree of the achieved sustainability for the HPLC reported technique and the produced UV ones were done by using the ideologies of the white analytical chemistry (WAC) tool. All the differences between the four aforementioned metrics are discussed in this study.

Generalized Entanglement Entropy and Holography

A nonextensive statistical mechanics entropy that depends only on the probability distribution is proposed in the framework of superstatistics. It is based on a Γ(χ2) distribution that depends on β and also on pl. The corresponding modified von Neumann entropy is constructed; it is shown that it can also be obtained from a generalized Replica trick. We address the question whether the generalized entanglement entropy can play a role in the gauge/gravity duality. We pay attention to 2dCFT and their gravity duals. The correction terms to the von Neumann entropy result more relevant than the usual UV (for c = 1) ones and also than those due to the area dependent AdS3 entropy which result comparable to the UV ones. Then the correction terms due to the new entropy would modify the Ryu-Takayanagi identification between the CFT entanglement entropy and the AdS entropy in a different manner than the UV ones or than the corrections to the AdS3 area dependent entropy.

Exploring the gauge/gravity duality of a generalized von Neumann entropy

We consider a generalized von Neumann entropy that depends only on the density matrix. This is based on a modification of Boltzmann-Gibbs entropy by considering non-equilibrium systems on stationary states, and an entropy functional depending only on the probability. We propose a generalization of the replica trick and find that the resulting modified von Neumann entropy is precisely the previously mentioned entropy that was obtained by other assumptions. Then, we address the question whether alternative entanglement entropies can play a role in the gauge/gravity duality. Our focus are 2d CFT and their gravity duals. Our results show corrections to the von Neumann entropy S0. If the central charge is small/large they are correspondingly larger/smaller than the usual UV ones and also than the corrections to the corresponding minimal length in AdS3, which are comparable to the UV ones. This agrees with previous results indicating that the generalized entropy is more relevant for systems with fewer degrees of freedom. The correction terms due to the new entropy would modify the Ryu-Takayanagi identification between the CFT and the gravitational AdS3 minimal length. We discuss the ingredients for computing the corresponding gravity duals of generalized entanglement entropies.

Generalized information and entanglement entropy, gravitation and holography

A nonextensive statistical mechanics entropy that depends only on the probability distribution is proposed in the framework of superstatistics. It is based on a Γ(χ2) distribution that depends on β and also on pl. The corresponding modified von Neumann entropy is constructed; it is shown that it can also be obtained from a generalized Replica trick. We further demonstrate a generalized H-theorem. Considering the entropy as a function of the temperature and volume, it is possible to generalize the equation of state of an ideal gas. Moreover, following the entropic force formulation a generalized Newton's law is obtained, and following the proposal that the Einstein equations can be deduced from the Clausius law, we discuss on the structure that a generalized Einstein's theory would have. Lastly, we address the question whether the generalized entanglement entropy can play a role in the gauge/gravity duality. We pay attention to 2d CFT and their gravity duals. The correction terms to the von Neumann entropy result more relevant than the usual UV ones and also than those due to the area dependent AdS3 entropy which result comparable to the UV ones. Then the correction terms due to the new entropy would modify the Ryu–Takayanagi identification between the CFT entanglement entropy and the AdS entropy in a different manner than the UV ones or than the corrections to the AdS3 area dependent entropy.

A coarse grained perturbation theory for the Large Scale Structure, with cosmology and time independence in the UV

Standard cosmological perturbation theory (SPT) for the Large Scale Structure (LSS) of the Universe fails at small scales (UV) due to strong nonlinearities and to multistreaming effects. In ref. [1] a new framework was proposed in which the large scales (IR) are treated perturbatively while the information on the UV, mainly small scale velocity dispersion, is obtained by nonlinear methods like N-body simulations. Here we develop this approach, showing that it is possible to reproduce the fully nonlinear power spectrum (PS) by combining a simple (and fast) 1-loop computation for the IR scales and the measurement of a single, dominant, correlator from N-body simulations for the UV ones. We measure this correlator for a suite of seven different cosmologies, and we show that its inclusion in our perturbation scheme reproduces the fully non-linear PS with percent level accuracy, for wave numbers up to k∼ 0.4 h Mpc-1 down to 0z=. We then show that, once this correlator has been measured in a given cosmology, there is no need to run a new simulation for a different cosmology in the suite. Indeed, by rescaling this correlator by a proper function computable in SPT, the reconstruction procedure works also for the other cosmologies and for all redshifts, with comparable accuracy. Finally, we clarify the relation of this approach to the Effective Field Theory methods recently proposed in the LSS context.

Passivation of defects in ZnO nanowires by SiO2 sputtering deposition

Passivation of native point defects in ZnO nanowires was successfully achieved by SiO2 deposition. The ZnO nanowires were grown on sapphire by the vapor–liquid–solid method and coated with SiO2 through reactive sputtering deposition. The samples were post-annealed at different temperatures in Argon atmosphere. Photoluminescence measurements at room temperature and electron transmission microscopy were performed. The coated nanowires present a core–shell structure. A strong oxygen vacancies passivation were observed resulting in a drastic suppression on visible light emissions in favor of UV ones. On the other hand, annealing at increasingly higher temperatures favored the oxygen desorption and the increase of deep-level states.

Blue/green/red colour emitting up-conversion phosphors coupled C-TiO2 composites with UV, visible and NIR responsive photocatalytic performance

The composites of C-TiO2 coupled with blue, green and red of three colours emitting up-conversion phosphors have been prepared by a simple calcination assisted solvothermal method. The composites of the narrow band gap of C-TiO2 and the unique optical property of up-conversion phosphors enabled to absorb UV, visible and NIR lights simultaneously to proceed photocatalytic reactions effectively. The photocatalytic activities of the composites were evaluated not only for the degradation of RhB solution under NIR light irradiation but also for the destruction of continuous NO gas under the irradiation of UV, visible LEDs and infrared laser. According to the photocatalytic results, the calculated photonic efficiency of infrared light induced photocatalytic activity of samples was much higher than those of UV and visible light responsive ones. Furthermore, the green light emitting up-conversion phosphor coupled C-TiO2 composite presented the superior photocatalytic performance over blue and red ones.

Temperature dependence of luminescence from scintillator LSO:Ce under VUV excitation

Luminescence properties of LSO:Ce, including the excitation spectra in 130–370 nm and the emission spectra in 350–500 nm as well as decay times were studied by synchrotron radiation at different temperature between 79 and 295 K. The temperature dependence of the VUV (178 nm) excitation band was different from that of the UV (264, 296 and 364 nm) ones of LSO:Ce luminescence (436 nm). The former had no thermo-quenching and the latter thermo-quenching was evident for both single crystal and powder sample. Not only the excitation spectra, but also the VUV excited emission spectra showed a temperature dependent behavior. The difference can be ascribed to a different energy transfer process in the LSO:Ce material under VUV and UV excitation. When the temperature rises from 79 to 295 K, the VUV excited luminescence decay times vary in the range of 27.6–32.4 ns for single crystal and from 29.8 to 25.5 ns for powder sample.

Efficient initiators for two-photon induced polymerization in the visible range

We present two derivatives of biphenyl or fluorene symmetrically substituted, which could initiate the two-photon absorption (TPA) photopolymerization of acrylates in the visible range. Both compounds show broadband TPA between 500 and 650 nm with cross-sections of, respectively, 30 and 80×10 −50 cm 4 s photon −1 at 532 nm, the photoinitiation wavelength. Threshold energies and dynamic ranges for polymerization were measured in both cases. As expected, the fluorene derivative was slightly more efficient than the biphenyl one. Our initiators appeared to be orders of magnitude more sensitive than the commercial UV ones, commonly used for TPA photopolymerization.

Micro- and macro-scale investigation of fractionation and matrix effects in LA-ICP-MS at 1064 nm and 266 nm on glassy materials

Fundamental processes taking place in UV and IR laser ablation and their significance for LA-ICP-MS measurements were investigated with synthetic glassy materials. LA-ICP-MS experiments were conducted on several vitreous and crystallized matrices with different composition using two Nd∶YAG laser ablation systems operating at 1064 nm and 266 nm. Macro-scale effects of the laser factors and matrix properties were evaluated with ICP-MS detection. In-situ investigation of the laser ablation process was carried out at the micro-scale to assess physical and chemical transformations of the original material, based on electron probe microanalysis of ablation products collected on filters and laser impacts. Fragments and beads in the 1–10 µm range enriched in refractory elements (Ca, Al) were characteristic of IR laser ablation, whereas sub-microscopic particles with similar composition to the original matrix were found for UV laser ablation. LA-ICP-MS response factors for matrix and minor elements appeared to be dependent on both the chemical composition and structure of the matrix (up to 30% and 60% for the UV and IR laser, respectively) and were also different for the two lasers by a factor 10. The use of La, a refractory matrix element, as an internal standard could compensate for differences in the ablation yield and thus limit matrix effects. However, fractionation effects were observed for the IR laser and also, to a lesser extent, with the UV one for volatile elements (e.g., Pb, As, B, Cs). Elemental fractionation effects were correlated with the oxide melting point of the elements as the LA-ICP-MS response factors for the IR laser normalized by the UV ones showed a linear relation with this parameter. At the micro-scale, the samples underwent physical and chemical differentiation that could be explained in terms of fusion, vaporization and fragmentation, resulting in the recombination of the analytes in the ablation products.

Loop-space formalism and renormalization group for the infrared asymptotics of QCD

It is demonstrated that the IR asymptotics of an arbitrary hard process of perturbative QCD can be factorized out into the superposition of vacuum averages of path-ordered exponentials, the IR singularities of which are shown to be in a one-to-one correspondence with the UV ones, thus allowing one to apply renormalization group methods to study the IR asymptotics of perturbative QCD. The anomalous dimension Γ cusp of the relevant RG equation is calculated up to two loops.