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It is shown that surfacing with feeding Nano oxides or Nano carbides into the weld pool leads to significant increase the wear resistance of deposited metal. Meanwhile, the information available in the literature on the optimal concentrations of Nano components corresponds only to specific surfacing conditions. Other surfacing conditions require additional experimental studies to determine optimal concentrations under these new conditions. Theoretical studies revealed that a change in the heat input of surfacing is accompanied by a change in the volume and mass of the weld pool, which leads to the changes in the mass concentrations of Nano components. It is shown that, the volume and mass of the weld pool may change almost by 3 times, and the mass percentage of Nano components by 2 times A method has been proposed for determining the mass fraction of Nano components in the weld pool at different heat inputs of surfacing. The experimental studies confirmed analytical predictions. The use of the proposed technique will make it possible to spread the technology of surfacing with feeding of Nano components into the weld pool without additional experimental studies. [ABSTRACT FROM AUTHOR]

In the current paper, the Cauchy problem for the inhomogeneous nonlinear Schrödinger equation including inverse-square potential is considered. First, some criteria of global existence and finite-time blow-up in the mass-critical and mass-supercritical settings with 0 < c ≤ c ∗ are obtained. Then, by utilizing the potential well method and the sharp Sobolev constant, the sharp condition of blow-up is derived in the energy-critical case with 0 < c < N 2 + 4 N (N + 2) 2 c ∗ . Finally, we establish the mass concentration property of explosive solutions, as well as the dynamic behaviors of the minimal-mass blow-up solutions in the L 2 -critical setting for 0 < c < c ∗ , by means of the variational characterization of the ground-state solution to the elliptic equation, scaling techniques and a suitable refined compactness lemma. Our results generalize and supplement the ones of some previous works. [ABSTRACT FROM AUTHOR]

We investigate the ground states of 3-component Bose–Einstein condensates with harmonic-like trapping potentials in ℝ 2 {\mathbb{R}^{2}} , where the intra-component interactions μ i {\mu_{i}} and the inter-component interactions β i ⁢ j = β j ⁢ i {\beta_{ij}=\beta_{ji}} ( i , j = 1 , 2 , 3 {i,j=1,2,3} , i ≠ j {i\neq j}) are all attractive. We display the regions of μ i {\mu_{i}} and β i ⁢ j {\beta_{ij}} for the existence and nonexistence of the ground states, and give an elaborate analysis for the asymptotic behavior of the ground states as β i ⁢ j ↗ β i ⁢ j * := a ∗ + 1 2 ⁢ (a ∗ - μ i) ⁢ (a ∗ - μ j) {\beta_{ij}\nearrow\beta_{ij}^{*}:=a^{\ast}+\frac{1}{2}\sqrt{{(a^{\ast}-\mu_{i% })(a^{\ast}-\mu_{j})}}} , where 0 < μ i < a ∗ := ∥ w ∥ 2 2 {0<\mu_{i}

Abstract The real-time continuous measurements of non-refractory submicron aerosol (NR-PM 1) species including organics (Org), sulfate (SO 4 2−), nitrate (NO 3 −), ammonium (NH 4 +) and chloride (Cl−) in winter from 10 December 2015 to 30 January 2016 in Beijing were performed with an Aerodyne Aerosol Chemical Speciation Monitor (ACSM). The average concentration of NR-PM 1 was 81.24 μg m−3, with the mean concentration in heavy haze days being 220.00 μg m−3, ∼3 times higher than that in light haze days and ∼15 times higher than that in clean days. Org was the most significant component of NR-PM 1 species, accounting for 53% of the total NR-PM 1 for the entire study. SO 4 2− was also a significant component, accounting for 23% of the total NR-PM 1. However, NO 3 −, NH 4 + and Cl− composition together accounted for 25% of the total NR-PM 1. All NR-PM 1 species presented remarkably diurnal cycles in haze days, characterized by the highest concentrations occurring at midnight, and the lowest concentrations occurring at daytime. Note that the sulfur oxidation ratios were higher than the nitrogen oxidation ratios for the entire study, especially during the haze periods. The formation of sulfate was mainly affected by relative humidity (RH), while that of nitrate was more associated with NH 3. Heterogeneous oxidation of NO 2 on the surfaces of aerosol particles might be a significant pathway of nitrate formations during haze periods. NR-PM 1 was mainly from secondary chemical reactions contributing 46.1%, vehicle emissions contributing 22.3%, coal combustion contributing 16.1%, and biomass burning contributing 15.6% in clean days. However, compared to the clean-day source contributions, the haze-day secondary source contribution to NR-PM 1 increased to 66.8%, indicating that NR-PM 1 in haze days was dramatically dominated by the secondary pollutants. Highlights • The formation of sulfate was mainly affected by relative humidity (RH), while that of nitrate was more associated with NH 3. • Heterogeneous oxidation of SO 2 might be a significant pathway of sulfate formations during haze periods. • Heterogeneous oxidation of NO 2 might be a significant pathway of nitrate formations during haze periods. • NR-PM 1 in haze days was dramatically dominated by the secondary pollutants. [ABSTRACT FROM AUTHOR]

Water and ions in or out of the mudstone have a profound effect on the rock strength, and studying the swelling ability can improve the prediction accuracy of wellbore stability. In this paper, a new equipment has been developed to continuously measure the swelling pressure of the mudstone in different solutions with different ions and different salinities. Moreover, the weight change of mudstone was acquired after the swelling pressure was in a steady state. Furthermore, triaxial compression test was performed to investigate the compressive strength and cohesion of rocks immersed in different water solutions. The results show that the higher the mass concentration of KCl is, the smaller the swelling pressure and the bigger the compressive strength will be. The compressive strength of mudstone contacting with KCl concentration is lower than that of the native mudstone. In addition, it is shown that the compressive strength and cohesion decrease while the swelling pressure increases. The relationship between the swelling pressure and uniaxial compressive strength can be described as an exponential function. Also, the cohesion can be expressed by an exponential function of swelling pressure. [ABSTRACT FROM AUTHOR]

This study presents a method to retrieve vertically-resolved profiles of dust mass concentrations by analyzing Raman lidar signals of silicon dioxide (quartz) at 546 nm. The observed particle plumes consisted of mixtures of East Asian dust with anthropogenic pollution. Our method for the first time allows for extracting the contribution of the aerosol component “pure dust” contained in the aerosol type “polluted dust”. We also propose a method that uses OPAC (Optical Properties of Aerosols and Clouds) and the mass concentrations profiles of dust in order to derive profiles of backscatter coefficients of pure dust in mixed dust/pollution plumes. The mass concentration of silicon dioxide (quartz) in the atmosphere can be estimated from the backscatter coefficient of quartz. The mass concentration of dust is estimated by the weight percentage (38–77%) of mineral quartz in Asian dust. The retrieved dust mass concentrations are classified into water soluble, nucleation, accumulation, mineral-transported and coarse mode according to OPAC. The mass mixing ratio of 0.018, 0.033, 0.747, 0.130 and 0.072, respectively, is used. Dust extinction coefficients at 550 nm were calculated by using OPAC and prescribed number concentrations for each of the 5 components. Dust backscatter coefficients were calculated from the dust extinction coefficients on the basis of a lidar ratio of 45 ± 3 sr at 532 nm. We present results of quartz-Raman measurements carried out on the campus of the Gwangju Institute of Science and Technology (35.10°N, 126.53°E) on 15, 16, and 21 March 2010. [ABSTRACT FROM AUTHOR]

The aerosol mass concentrations of total suspended particles (TSP: particles with diameter < 100 µm) and particulate matter (PM10 and PM2.5) were studied at three sites (two urban and one rural) in China's Yangtze River Delta (YRD) during the spring and winter of 2009. Aerosol mass concentrations prevalent during four typical weather conditions in the YRD were then analysed. Major events such as dust storms weakened the impact of TSP, PM10 and PM2.5 concentrations on the generation and dissipation of haze. During stable weather conditions such as cold high pressure, the impact of concentrations of TSP, PM10 and PM2.5 on the generation and dissipation of haze strengthened. When aerosol concentrations are low, even if local meteorological conditions remain favourable, mist is likely to be formed instead of haze. When concentrations are high, and local meteorological conditions are favourable, fog/haze conversion occurs. [ABSTRACT FROM AUTHOR]

The first simultaneous aethalometer and solar radiometer measurements of black carbon (BC) mass concentration (surface-level) and aerosol optical, microphysical and radiative parameters (columnar) have been made during 2005–2011 over two contrasting experimental sites, one representing background rural environment (Sinhagad) and the other surrounded by urban environment (Pune) in the south-west India. The long-term diurnal cycle of BC aerosols over both sites exhibited a strong peak during daytime and a weaker plateau around evening–midnight hours, implying the influence of anthropogenic emissions as well as changes in planetary boundary layer (PBL). The multi-year seasonal mean variation in BC concentration shows the highest during winter and lowest during monsoon seasons, which is found to be inversely related to the variations in single scattering albedo (SSA). Moreover, the BC variations were found to be strongly associated with greater values of Angstrom exponent ( α ), indicating that the observed BC involves abundance of fine-mode aerosol fraction. The higher concentrations of BC during winter and lower concentrations during pre-monsoon over both Pune and Sinhagad are noticed to be closely linked with aerosol optical depth, revealing significant contribution of BC to the composite aerosol over both the regions. The columnar AOD and Angstrom exponent also showed relatively greater optical depth and α values during winter as compared to pre-monsoon season over both sites. [ABSTRACT FROM AUTHOR]

We study blow-up, global existence and ground state solutions for the N-coupled focusing nonlinear Schrödinger equations. Firstly, using the Nehari manifold approach and some variational techniques, the existence of ground state solutions to the equations (CNLS) is established. Secondly, under certain conditions, finite time blow-up phenomena of the solutions is derived. Finally, by introducing a refined version of compactness lemma, the L concentration for the blow-up solutions is obtained. [ABSTRACT FROM AUTHOR]

We consider two-dimensional Bose-Einstein condensates with attractive interaction, described by the Gross-Pitaevskii functional. Minimizers of this functional exist only if the interaction strength a satisfies $${a < a^* = \|Q\|_2^2}$$ , where Q is the unique positive radial solution of $${\Delta u - u + u^3 = 0}$$ in $${\mathbb{R}^2}$$ . We present a detailed analysis of the behavior of minimizers as a approaches a*, where all the mass concentrates at a global minimum of the trapping potential. [ABSTRACT FROM AUTHOR]

This paper is concerned with a mass concentration phenomenon for a two-dimensional nonelliptic Schrödinger equation. It is well known that this phenomenon occurs when the ${L}^{4} $-norm of the solution blows up in finite time. We extend this result to the case where a mixed norm of the solution blows up in finite time. [ABSTRACT FROM AUTHOR]