Rotational analysis of the B2Σ+ → X2Σ+ system of the aluminum monoxide radical,AlO

Twenty-five bands of the B²Σ → X²Σ system of AlO with 0 ≤ v′ ≤ 9 and 0 ≤ v″ ≤ 6 have been photographed at high resolution. The measured positions of the assigned lines of each band have been fitted by least-squares to obtain estimates of the constants (B′, D′, B″, D″), the band origin, and Δγ_v′,v″, which is the difference of the upper and lower state spin-doubling constants (γ′_v and γ″_v). The parameters from individual bands have been merged to single-valued estimates, as well as to polynomial representations in ($\text{v +}\text{1}\text{2}$). Although the spin-doubling constants are not found absolutely for either state, their vibrational dependences are well determined. The data are employed in the computation of RKR potential energy curves and an array of Franck-Condon factors and r-centroids.     

On the trace and the relativistic scalar products involving Dirac matricesγ i and the 4 × 4 unit matrix

In this paper we have dealt with the relativistic scalar products likeγ _i uγ _i,Tr(γ _i u) Tr(γ _i v) and Tr(γ _i γ _j v). Here any string likeu andv involve Dirac matrices in the manneru=Π _n ^r=1 a _r where the element \(a_r = a_{r_i } \gamma _i + ia_{r_5 }\) i.e.,a _r in general involves a term \(ia_{r_5 }\) which is multiplied by a 4 × 4 unit matrix. We have further evaluated Tr (γ _b u) Tr (γ _b v) where the suffix ‘b’, unlike the dummy suffixesi andj, does not imply any summation and can assume any specific value from 1 to 5. Some reduction formulae for the evaluation of Tr (γ₅ u) and Tr(u) have been obtained in this paper.     

Measurement of hydrogen- and self-broadened half-widths of ammonia at 200 and 300°K

The hydrogen- and self-broadened half-widths have been measured for the (v₁+v₂)- and (v₂+v₃)-bands of ammonia at 300 and 207°K. Measurement of hydrogen-broadened widths has been restricted to J, K ?6, but that of self-broadened widths is done for a few lines outside that range. Assuming a power-law dependence of half-width on temperature given by γ(T)=γ(T₀)(T/T₀)^α, the average value of the index α for the lines measured is found to be 0·57 for hydrogen broadening.     

Two dimensional fractional projectile motion in a resisting medium

In this paper we propose a fractional differential equation describing the behavior of a two dimensional projectile in a resisting medium. In order to maintain the dimensionality of the physical quantities in the system, an auxiliary parameter k was introduced in the derivative operator. This parameter has a dimension of inverse of seconds (sec)^?1 and characterizes the existence of fractional time components in the given system. It will be shown that the trajectories of the projectile at different values of γ and different fixed values of velocity v ₀ and angle θ, in the fractional approach, are always less than the classical one, unlike the results obtained in other studies. All the results obtained in the ordinary case may be obtained from the fractional case when γ = 1.     

On the relationship between the apparent diffusion coefficient and extravascular extracellular volume fraction in human breast cancer

MRI techniques have been developed that can noninvasively probe the apparent diffusion coefficient (ADC) of water via diffusion-weighted MRI (DW-MRI). These methods have found much application in cancer where it is often found that the ADC within tumors is inversely correlated with tumor cell density, so that an increase in ADC in response to therapy can be interpreted as an imaging biomarker of positive treatment response. Dynamic contrast enhanced MRI (DCE-MRI) methods have also been developed and can noninvasively report on the extravascular extracellular volume fraction of tissues (denoted by v_e). By conventional reasoning, the ADC should therefore also be directly proportional to v_e. Here we report measurements of both ADC and v_e obtained from breast cancer patients at both 1.5 and 3.0 T. The 1.5-T data were acquired as part of normal standard of care, while the 3.0-T data were obtained from a dedicated research protocol. We found no statistically significant correlation between ADC and v_e for the 1.5- or 3.0-T patient sets on either a voxel-by-voxel or a region-of-interest (ROI) basis. These data, combined with similar results from other disease sites in the literature, may indicate that the conventional interpretation of either ADC, v_e or their relationship is not sufficient to explain experimental findings.     

Energy spectrum of photons produced by neutrino (antineutrino) scattering on electrons. Effect of possible neutrino oscillations

The energy spectrum of photons emitted in neutrino (antineutrino) scattering on electrons at E_v ? m_v is calculated with the assumption that the neutral electron flow has an arbitrary (V, A) structure. The result obtained is generalized to the case of possible neutrino oscillations, \(v_e \begin{array}{*{20}c} { - \to } \\ { \leftarrow - } \\ \end{array} v_\mu , \overline v _e \begin{array}{*{20}c} { - \to } \\ { \leftarrow - } \\ \end{array} \overline v _\mu \) , at an arbitrary neutrino mixing angle. Using the Weinberg-Salam model (sin²θ_W = 0.23) estimates of the sections dσ_γ/dω and σ_γ are obtained with consideration of the reactor antineutrino flux \(\bar v_e \) . The contributions from charged and neutral lepton fluxes and their interference to dσ_γ/dω are compared.     

Difference frequency laser spectroscopy of OH and OD: Simultaneous fit of the infrared and microwave lines

The fundamental vibration rotation bands of OH and OD have been observed with an estimated accuracy of 0.001 cm^?1. Simultaneous fits of the infrared and microwave data are performed to improve the molecular constants in the v = 0 and v = 1 states. The correlated parameters γ_v and A_D are determined by combining the data for OH and OD. Some discussion is presented on the correlated molecular parameters.     

Dynamical continuous time random Lévy flights

The Lévy flights’ diffusive behavior is studied within the framework of the dynamicalcontinuous time random walk (DCTRW) method, while the nonlinear friction is introduced ineach step. Through the DCTRW method, Lévy random walker in each step flies by obeying theNewton’s Second Law while the nonlinear friction f(v) = ?γ₀v ?γ₂v³ beingconsidered instead of Stokes friction. It is shown that after introducing the nonlinearfriction, the superdiffusive Lévy flights converges, behaves localization phenomenon withlong time limit, but for the Lévy index μ = 2 case, it is still Brownian motion.     

Assessment of a combined spin- and gradient-echo (SAGE) DSC-MRI method for preclinical neuroimaging

The goal of this study was to optimize and validate a combined spin- and gradient-echo (SAGE) sequence for dynamic susceptibility-contrast magnetic resonance imaging to obtain hemodynamic parameters in a preclinical setting. The SAGE EPI sequence was applied in phantoms and in vivo rat brain (normal, tumor, and stroke tissue). Partial and full Fourier encoding schemes were implemented and characterized. Maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), vessel size index (VSI), volume transfer constant (K^trans), and volume fraction of the extravascular extracellular space (v_e) were obtained. Partial Fourier encoding provided shortened echo times with acceptable signal-to-noise ratio and temporal stability, thus enabling reliable characterization of T₂, T₂^? and T₁ in both phantoms and rat brain. The hemodynamic parameters CBV, CBF, and MTT for gradient-echo and spin-echo contrast were determined in tumor and stroke; VSI, K^trans, and v_e were also computed in tumor tissue. The SAGE EPI sequence allows the acquisition of multiple gradient- and spin-echoes, from which measures of perfusion, permeability, and vessel size can be obtained in a preclinical setting. Partial Fourier encoding can be used to minimize SAGE echo times and reliably quantify dynamic T₂ and T₂^? changes. This acquisition provides a more comprehensive assessment of hemodynamic status in brain tissue with vascular and perfusion abnormalities.     

Dating problems with selected mining lakes and the adjacent groundwater body in Lusatia,Germany

This study presents selected results, applying environmental tracers to investigate lake water–groundwater interactions at two study sites located in Lusatia, Germany. The focus of the investigations were two meromictic pit lakes and their adjacent aquifers. In order to follow hydrodynamic processes between lake and groundwater, mixing patterns within the lakes as well as ages of lake and groundwater, water samples of ground- and lake water were collected at three occasions, representing summer and winter conditions in the aquatic systems. The water samples were analysed for stable isotopes (deuterium, oxygen-18) and tritium and sulphurhexafluoride (SF₆ concentration). Lake water profiles of conductivity and ¹⁸O could validate the permanent stratification pattern of both the lakes. Groundwater data sets showed a heterogeneous local distribution in stable isotope values between rain and lake water. A two-component mixing model had been adopted only from ¹⁸O data to determine lake water proportions in the surrounding groundwater wells in order to correct measured tritium and SF₆ concentrations in groundwater samples. This procedure had been hampered by upstream-located wells indicating strong ¹⁸O enrichment in groundwater samples. However, rough groundwater ages were estimated. For both study sites, Piston flow ages between 12.9 and 27.7 years were calculated. The investigations showed the good agreement between two different environmental dating tools, considering the marginal data sets.     

Study of the torsion-rotation Hamiltonian for symmetric tops using the millimeter wave spectrum of methyl silane

The torsion-rotation Hamiltonian for symmetric tops has been tested in methyl silane by combining recent anticrossing molecular beam measurements in the ground torsional state (v = 0) with pure rotational spectra taken for v as high as 4. The earlier microwave data set which consisted of J = 1 ← 0 and 2 ← 1 has been greatly extended by studying millimeter transitions for J = 4 ← 3, 5 ← 4, and 13 ← 12. An analysis of the 72 rotational frequencies for v ≤ 2 and the 15 anticrossing data for v = 0 yielded an excellent fit using 14 rotational, torsional, and distortion constants including the effective values for the A rotational constant and the barrier height V₃. No satisfactory fit could be obtained when the data set was extended to include measurements for (v = 3) or (v = 4). For each of these higher torsional levels, the difference between the observed frequencies and the predictions based on the best (v ≤ 2) constants can be expressed in terms of a shift δB_v in the B rotational constant, where δB_v is a smooth function of the torsional energy. This disagreement is of particular interest because it may result from the fact that the molecule passes from hindered to free rotation as v is increased from 2 to 4. The possibility of perturbation by a low-lying vibrational level is considered briefly. The information contained in the different types of spectra is discussed; the redundancy relations are treated and a Fourier expansion of the diagonal torsional matrix elements is introduced. For ¹²CH₃²⁹SiH₃, ¹²CH₃³⁰SiH₃, and ¹³CH₃²⁸SiH₃ pure rotational spectra for v = 0 were studied briefly in natural abundance. The results were combined with existing data for two deuterated symmetric rotors to obtain a structure based only on symmetric top rotational constants.     

Rotational components of the v8 = 1, 2, and 3 and ground vibrational levels of CH3C15N for the frequency range 17–75 GHz

The microwave spectrum of methyl cyanide CH₃C¹⁵N was studied for the v₈ = 3 vibrational state in the frequency range of 17 to 75 GHz. In addition, some rotational components for the ground, v₈ = 1 and 2 were remeasured and these results compared to those found in the literature. The frequencies of 42 components were measured and these frequencies were used to produce a constant set which can be used to predict overall frequencies of spectral components in the ground, v₈ = 1, 2 up to an accuracy of 100 KHz and those for v₈ = 3, 4 up to an accuracy of 150 KHz. Previously obtained experimental data, available from the literature, and our own data for the ground, v₈ = 1 and 2, and the new data for v₈ = 3 are presented and compared with the frequencies obtained from a comprehensive equation derived from perturbation techniques.     

Analysis of n(87Sr)/n(86Sr), δ88Sr/86SrSRM987 and elemental pattern to characterise groundwater and recharge of saline ponds in a clastic aquifer in East Austria

Elemental and isotopic pattern of n(⁸⁷Sr)/n(⁸⁶Sr) and δ⁸⁸Sr/⁸⁶Sr_SRM987 were used to characterise groundwater and recharge of saline ponds in a clastic aquifer in East Austria. Therefore, shallow, artesian and thermal groundwaters of the investigated aquifer along with rainfall and rivers were analysed using (MC) ICP-MS. The n(⁸⁷Sr)/n(⁸⁶Sr) ratio and elemental pattern changed with aquifer depth as a result of progressing bedrock leaching and dissolution with increasing groundwater residence time. The n(⁸⁷Sr)/n(⁸⁶Sr) ratio of shallow groundwater below saline ponds of 0.71019?±?0.00044 was significantly different from thermal groundwater of 0.71205?±?0.00035 (U, k?=?2). In contrast to previous theories, this result suggested no recharge of saline ponds by upwelling paleo-seawater. Isotope pattern deconvolution revealed that rainfall accounted to about 60% of the n(⁸⁷Sr)/n(⁸⁶Sr) ratio of shallow groundwater below saline ponds. The δ⁸⁸Sr/⁸⁶Sr_SRM987 values of groundwater decreased from about 0.25 ‰ in most shallow, to predominantly negative values of about –0.24 ‰ in artesian groundwater. This result indicated leaching and dissolution of weathered minerals. In turn, the δ⁸⁸Sr/⁸⁶Sr_SRM987 of deep thermal groundwater showed positive values of about 0.12 ‰, which suggested removal of ⁸⁶Sr from solution by carbonate precipitation. These results highlight the potential of δ⁸⁸Sr/⁸⁶Sr_SRM987 signature as an additional geochemical tracer.     

Revision of spectral parameters for the B- and γ-bands of oxygen and their validation against atmospheric spectra

Until recently the B (b¹Σ_g⁺ (v=1)−X³Σ_g⁻ (v=0)) and γ (b¹Σ_g⁺ (v=2)−X³Σ_g⁻ (v=0)) bands of oxygen in the visible region had not been used extensively in satellite remote sensing of the atmosphere. These bands roughly cover the regions around 14,527 and 15,904 cm⁻¹, respectively (0.69 and 0.63 μm). However, these bands (in particular the B-band) are now being increasingly considered for future satellite missions. In this light, it is important to make sure that the reference spectroscopic parameters allow accurate retrieval of important physical characteristics from the atmospheric spectra. The spectroscopic parameters currently given for these bands in the HITRAN2008 spectroscopic database were tested against high-resolution atmospheric spectra measured with solar-pointing Fourier transform spectrometers at Park Falls, Wisconsin (B-band) and Kitt Peak, Arizona (γ-band). It was found that the current HITRAN parameters cannot produce satisfactory fits of the observed spectra. In order to improve the database we have collected the best available measured line positions that involve the b¹Σ_g⁺ (v=1 and v=2) states for the three most abundant isotopologues of oxygen and performed a combined fit to obtain a consistent set of spectroscopic constants. These constants were then used to calculate the line positions. A careful review of the available intensity and line-shape measurements was also carried out, and new parameters were derived based on that review. In particular, line shift parameters, that were not previously available, were introduced. The new data have been validated using the high-resolution atmospheric spectra measured with the Fourier transform spectrometers at Park Falls, Wisconsin (B-band) and Kitt Peak, Arizona (γ-band) and have yielded substantial improvement. In addition, we report the first direct observation and analysis of the ¹⁶O¹⁸O lines in the γ-band.     

The decay of theT=1 isospin triplet inA=12 systems

A complete theoretical study is carried out of the beta decays of the¹²B and¹²N ground states to the¹²C ground state. We calculated the form factor coefficientsF _KLs ^N (k_e, m, n, ρ) using the Cohen-Kurath wave functions. In particular, we obtained reasonable values for the form factor coefficients ^A F ₁₀₁ ⁰ and ^v F ₁₁₁ ⁰ whose ratio contains the influence of the weak magnetism coupling constant. It is shown that in this way the measurements of the shape factors presented by Wu and coworkers can be explained. In addition, it is demonstrated that the contribution of the term proportional to (WR)² cannot be completely neglected because of the large end point energyW ₀. From our value of ^v F ₁₁₁ ⁰ we have derived the radiative widthΓ _γ (M1) of the isobaric analogγ transition from the excited state¹²C^* to the ground state of¹²C. The result is in good agreement with the experimental data. For both beta transitions we have evaluated theft values which are in good agreement with the experimental values. It is confirmed that the difference between theft values for both beta transitions can be accounted for by binding energies effects.     

Influence of charginos on the decay rate ofZ 0→Hγ with and withoutR-parity breaking

We present a detailed calculation for the decay rate ofZ ⁰→Hγ, when charginos are taken into account inside the relevant penguin diagram. One result is that supersymmetry can suppress the contribution of the graph withW-bosons in the loop. We also give a detailed calculation of the exact mass eigenstates of the charginos and the real parts of the Higgs particles, when the scalar tau neutrino gets a vacuum expectation valuev _τ. We show thatv _τ≠0 enhances the influence on the decay rateZ ⁰→Hγ.     

Optical characterization of nano-structured Cu2ZnSnS4 thin films deposited by GLAD technique

In this paper, Cu₂ZnSnS₄ (CZTS) thin films were elaborated at room temperature by thermal evaporation method using Glancing Angle Deposition (GLAD) technique at different incident angles γ = 00°, 20°, 40°, 60°, 75° and 85°. XRD, Raman scattering analysis, (SEM) and UV-Visible-NIR spectroscopy were used to characterize the crystalline structure, morphology and optical properties of CZTS samples. The results have showed that the ellipsometric analysis leaded to an optical anisotropy due to the structural anisotropy for CZTS samples deposited at γ = 85°. All Cu₂ZnSnS₄ samples exhibited a high absorption coefficient (α > 10⁴ cm⁻¹) and a direct optical transition varied between 1.48 eV and 2.05 eV for CZTS thin films deposited at γ = 00° and 85°, respectively. The value of the Urbach energy increased with incident angle, indeed, its value increased from 58 meV (γ = 00°) to 604 meV (γ = 75°) and decrease to be 368 meV for γ = 85°. This result is correlated with the Raman analysis. From transmittance data of CZTS thin films deposited at γ = 00°, 20° and 40° Swanepoel's method was used, to estimate the refractive index n. It allows us, using the Wemple-DiDomenico and Spitzer-Fan models, to calculate other optical parameters such as the oscillator energy E₀, dispersion energy E_d, zero frequency refractive index n₀, high frequency dielectric constant ε_∞ and the electric susceptibility χ_e. On the other hand, to have an idea about the evolution of the nonlinear optical character, the nonlinear susceptibility χ⁽³⁾ and the nonlinear refractive index n₂ of CZTS thin films deposited at γ = 00°, 20° and 40° were investigated. Ellipsometric measurements of CZTS thin films has leaded to an optical anisotropy for γ = 85°. In addition, the generalized ellipsometry in Jones formalism have proved this property, which can be related to the nano-columnar slanted structure as revealed by (SEM) analysis.     

Chemical effects of high‐resolution YbLγ4 emission spectra: a possible probe for chemical analysis

An ‘eccentric’ X‐ray emission, YbLγ₄, was measured for Yb metal, Yb₂O₃, YbF₃, β‐YbAlB₄, YbNi₃Al₉, and YbNi₃Ga₉ with a resolution of ~0.9 eV. Peak splitting of the YbLγ₄ line was observed in all the recorded spectra and was attributed to the two components originating from the LS coupling of the Yb5p hole, the Yb5p_1/2 (L_IO_II: Lγ₄′) and Yb5p_3/2 components (L_IO_III: Lγ₄). The spectra were substantially different depending on the chemical environment of Yb. The position of the Lγ₄ + Lγ₄′ band shifts depending on the valence of Yb (v): ~4.4 eV from divalent to trivalent. The Lγ₄ + Lγ₄′ spectra of the mixed valence intermetallics, i.e. YbNi₃Ga₉ (v = 2.59) and β‐YbAlB₄ (v = 2.75), were fairly well reproduced by averaging the spectra of divalent Yb and trivalent YbNi₃Al₉, which suggests the possibility of using the YbLγ₄ emission for determining the valence of Yb intermetallics. In trivalent Yb compounds, the relative intensity of Lγ₄ compared with that of Lγ₄′, as well as the appearance of a high‐energy satellite, was found to be influenced by the ligands around the Yb ions. With the aid of preliminary atomic multiplet and band structure calculations, the differences in the valence band structure and resultant screening effects on the O_II,III^?1 states were determined to be the possible causes for the observed ligand dependence. © 2013 The Authors. X‐ray spectrometry published by John Wiley & Sons, Ltd.     

Optimized Selection of Water Resource Allocation Schemes Based on Improved Connection Entropy in Beijing’s Southern Plain

Increased urbanization has caused problems such as increasing water consumption and the continuous deterioration of the groundwater environment. It is necessary to consider the groundwater quality in the water resource optimization system and increase the rate of reclaimed water development to reduce the amount of groundwater exploitation and achieve sustainable development of water resources. This study used the Daxing District, a region of Beijing’s southern plain, as an example to evaluate water quality by analyzing water quality data of surface and groundwater from 2012 to 2016 and actual water-use schemes from 2006 to 2016. Three groundwater extraction modes were set up based on NO₃–N concentrations, water resources were optimized under three extraction modes, and water resource optimization schemes were determined based on the improved connection entropy. The results show that (1) the surface water quality was poor, and the proportion of V₄ type water in the indexes of NH₃–N and chemical oxygen demand (COD) was the largest. The surface water can only be used for agricultural irrigation. The pollution sources contributing most to NH₃–N and COD were domestic and agricultural pollution sources. (2) The groundwater quality was good. The NO₃–N index was primarily type I–III water, accounting for 95.20% of the total samples. Severe NH₃–N pollution areas were mainly in the northern region, and most regional groundwater can be used for various purposes. (3) Taking 2016 as an example, three groundwater exploitation modes were set to optimize water resource allocation, and the results showed that the rate of groundwater development and NO₃–N pollution decreased significantly after optimization. (4) Connection entropy is an evaluation method that combines connection numbers and entropy, including identify, difference, and opposition entropy. As connection entropy being a kind of complete entropy, which can reflect the difference of the system in different states, based on the improved connection entropy, the connection entropies of optimal water resource allocation and actual water-use schemes were calculated. The connection entropy of groundwater exploitation mode 3 was less than that of groundwater exploitation modes 1 and 2 and actual water-use schemes from 2006 to 2016. Therefore, exploitation mode 3’s water resource optimization scheme was recommended. In the paper, satisfactory results have been obtained. As a kind of complete entropy, connection entropy has great research value in dealing with complex hydrological problems. This study’s research methods and outcomes can provide methodological and theoretical lessons for water management in freshwater-deficient areas.