Arrest of self-focusing collapse in femtosecond air filaments: higher order Kerr or plasma defocusing?

Experimentally measured conical emission rings on the blue side of the filament supercontinuum of a 800 nm 50 fs pulse in air are reproduced in simulations with plasma and the third-order Kerr as the nonlinear terms. This agreement indicates plasma as the dominant mechanism arresting the self-focusing collapse. The higher order Kerr terms with the recently measured coefficients stop the collapse at a lower intensity than the plasma does and lead to the spherical angle-wavelength spectrum without blueshifted rings.     

Design,synthesis and investigation of the interaction behavior between two acridone derivatives, 8-chloro acridone and nitrile cyanide acridone with calf thymus DNA,by different spectroscopic techniques

Journal of the Iranian Chemical Society - Evaluating the binding interaction between biomacromolecules and various chemical compounds is one of the most biologically researched topics. The present...     

High-pressure phase equilibrium calculations for carbon dioxide + cyclopentane binary system

The phase behavior of the carbon dioxide + cycloalkane mixtures usually receives low attention, though these systems are important for many industries, e.g. the carbon capture and storage. In this paper calculations results for the carbon dioxide + cyclopentane binary system are presented, based on SRK and PR cubic equations of state with classical van der Waals mixing rules. A single set of binary parameters for each model was proposed to predict the global phase behavior of the system in a wide range of pressure and temperature. Albeit the thermodynamic models used are simple, they are able to represent fairly well the phase behavior of the system analyzed in this paper.

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Green synthesis of amorphous calcium phosphate nanopowders using Aloe Vera plant extract and assessment of their cytotoxicity and antimicrobial activities

Journal of Sol-Gel Science and Technology - Considering the existing various sources that can supply the nano-biomaterials that are related to the Amorphous Calcium Phosphate (ACP) family, Aloe...     

Uncertainties in neutron activation analysis resulting from reactor noise

The stochastic processes of activation, disintegration and counting have been studied, taking into account reactor noise. Deviation of the variance of the number of counts from Poisson limit is shown to result. Explicit expressions for the variance in the case of Markovian autocorrelation function of the neutron flux density are presented and their relevance to neutron activation analysis is discussed.Presented at the MTAA-8 Conference, September 16–20, 1991, Vienna, Austria.     

Activity of a cationic carotenoid derivative in a mouse model of protoporphyria

Prior work using cell culture has shown that certain synthetic carotenoid derivatives are more effective than natural carotenoids in preventing photosensitized cell killing. These carotenoid derivatives are either cationic or are weak bases. We have now found that of one of these derivatives, the Girard's reagent T derivative of beta-apo-8'-carotenal (GRT-carotenal) decreases acute photosensitivity in a mouse model of protoporphyria. When GRT-carotenal was added to the diet of SKH1 mice, both GRT-carotenal and its metabolites accumulated in the skin of the mice. Protoporphyria was induced in SKH1 mice by adding collidine to their diet. When the porphyric mice were exposed to 400 nm light (2.6+/-0.1 mW cm(-2)) for a period of 2h, the skin on the backs of these animals increased in thickness. Increased vascularity also developed in the skin of the mouse ears. Animals, that were fed a diet containing both collidine and GRT-carotenal and then exposed to light, had significantly smaller increases in skin thickness and less prominent increases in the vascular pattern on their ears.     

The Effect of Functional Groups on the Phase Behavior of Carbon Dioxide Binaries and Their Role in CCS

In recent years we have focused our efforts on investigating various binary mixtures containing carbon dioxide to find the best candidate for CO₂ capture and, therefore, for applications in the field of CCS and CCUS technologies. Continuing this project, the present study investigates the phase behavior of three binary systems containing carbon dioxide and different oxygenated compounds. Two thermodynamic models are examined for their ability to predict the phase behavior of these systems. The selected models are the well-known Peng–Robinson (PR) equation of state and the General Equation of State (GEOS), which is a generalization for all cubic equations of state with two, three, and four parameters, coupled with classical van der Waals mixing rules (two-parameter conventional mixing rule, 2PCMR). The carbon dioxide + ethyl acetate, carbon dioxide + 1,4-dioxane, and carbon dioxide + 1,2-dimethoxyethane binary systems were analyzed based on GEOS and PR equation of state models. The modeling approach is entirely predictive. Previously, it was proved that this approach was successful for members of the same homologous series. Unique sets of binary interaction parameters for each equation of state, determined for the carbon dioxide + 2-butanol binary model system, based on k₁₂–l₁₂ method, were used to examine the three systems. It was shown that the models predict that CO₂ solubility in the three substances increases globally in the order 1,4-dioxane, 1,2-dimethoxyethane, and ethyl acetate. CO₂ solubility in 1,2-dimethoxyethane, 1.4-dioxane, and ethyl acetate reduces with increasing temperature for the same pressure, and increases with lowering temperature for the same pressure, indicating a physical dissolving process of CO₂ in all three substances. However, CO₂ solubility for the carbon dioxide + ether systems (1,4-dioxane, 1,2-dimethoxyethane) is better at low temperatures and pressures, and decreases with increasing pressures, leading to higher critical points for the mixtures. By contrast, the solubility of ethyl acetate in carbon dioxide is less dependent on temperatures and pressures, and the mixture has lower pressures critical points. In other words, the ethers offer better solubilization at low pressures; however, the ester has better overall miscibility in terms of lower critical pressures. Among the binary systems investigated, the 1,2-dimethoxyethane is the best solvent for CO₂ absorption.     

Influence of Pyrolytic Biochar on Settleability and Denitrification of Activated Sludge Process

Biochar is a massively produced by-product of biomass pyrolysis to obtain renewable energy and has not been fully used.Incomplete separation of sludge and effluent and insufficient denitrification of sewage are two of main factors that influence the efficiency of activated sludge process.In this work,we proposed a new utilization of biochar and investigated the effect of biochar addition on the performance of settleability and denitrification of activated sludge.Results show that the addition of biochar can improve the settleability of activated sludge by changing the physicochemical characteristics of sludge (e.g.,flocculating ability,zeta-potential,hydrophobicity,and extracellular polymeric substances constituents).Moreover,the dissolved organic carbon released from biochar obtained at lower pyrolysis temperature can improve the nitrate removal efficiency to a certain extent.     

Prostate‐Cancer‐Targeted N‐(2‐Hydroxypropyl)methacrylamide Copolymer/Docetaxel Conjugates

Biodistribution, pharmacokinetics, and efficacy of prostate‐cancer‐targeted HPMA copolymer/DTX conjugates are evaluated in nude mice bearing prostate cancer C4‐2 xenografts. PSMA‐specific monoclonal antibodies 3F/11 are used as the targeting moiety. Control conjugates contain either non‐specific IgG or no IgG. The ratios of tumor accumulation to total background organs (heart, lung, kidney, liver, spleen and blood) accumulation increase substantially with time for the targeted conjugate, and the ratio at 48 h is 7‐fold higher than that at 6 h. Preliminary evaluation of the efficacy of the conjugates in vivo show tumor growth inhibition for all HPMA copolymer/DTX conjugates.