67 research outputs found
Luminescence and formation of alkali-halide ionic excimers in solid Ne and Ar
Transitions from ionic states A²⁺X– of alkalihalides CsF, CsCl and RbF isolated in solid Ne and Ar films recorded under pulsed e-beam excitation are studied. The B(²∑₁/₂)-X(²∑₁/₂) and C(²П₃/₂)-A(²П₃/₂) luminescence bands of Cs2+F– (196.5 nm, 227 nm), Cs²⁺Cl– (220.1 nm, 249.2 nm) and Rb²⁺F– (136 nm) in Ne, and a weakerB–X emission of Cs²⁺F– (211.2 nm) in Ar are identified. For CsF the depopulation of the A²⁺X– state is dominated by the radiative decay. A ratio of the recorded exciplex emission intensities of I(CsF)/I(CsCl)/I(RbF) = 20/5/1 reflects the luminescence efficiency and for RbF and CsCl a competitive emission channel due to predissociation in the A²⁺X⁻(B²∑₁/₂) state is observed. For these molecules an efficient formation of the state X*₂ is confirmed through recording the molecular D`(³П₂g)-A`(³П₂u) transition. A strong dependence of the luminescence intensities on the alkalihalide content reveals quenching at concentrations higher than 0.7%
In vitro assessment of antimicrobial, antioxidant, and cytotoxic properties of Saccharin-Tetrazolyl and-Thiadiazolyl derivatives: the simple dependence of the pH value on antimicrobial activity
The antimicrobial, antioxidant, and cytotoxic activities of a series of saccharin-tetrazolyl and -thiadiazolyl analogs were examined. The assessment of the antimicrobial properties of the referred-to molecules was completed through an evaluation of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against Gram-positive and Gram-negative bacteria and yeasts. Scrutiny of the MIC and MBC values of the compounds at pH 4.0, 7.0, and 9.0 against four Gram-positive strains revealed high values for both the MIC and MBC at pH 4.0 (ranging from 0.98 to 125 µg/mL) and moderate values at pH 7.0 and 9.0, exposing strong antimicrobial activities in an acidic medium. An antioxidant activity analysis of the molecules was performed by using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, which showed high activity for the TSMT (N-(1-methyl-2H-tetrazol-5-yl)-N-(1,1-dioxo-1,2-benzisothiazol-3-yl) amine, 7) derivative (90.29% compared to a butylated hydroxytoluene positive control of 61.96%). Besides, the general toxicity of the saccharin analogs was evaluated in an Artemia salina model, which displayed insignificant toxicity values. In turn, upon an assessment of cell viability, all of the compounds were found to be nontoxic in range concentrations of 0-100 µg/mL in H7PX glioma cells. The tested molecules have inspiring antimicrobial and antioxidant properties that represent potential core structures in the design of new drugs for the treatment of infectious diseases.Funding Agency
Portuguese Foundation for Science and Technology
UID/QUI/00100/2019
UID/MULTI/04326/2019 -CCMAR
Portuguese Foundation for Science and Technology
SFRH/BPD/99851/2014
IST-ID/115/2018info:eu-repo/semantics/publishedVersio
Comparison of the skin surface temperature on the front of thigh after application of combined red-IR radiation and diadynamic currents executed in a different sequence
Repairing digger/loaders’ body construction whit the use of microjet cooling
W artykule przeanalizowano zastosowanie chłodzenia metodą mikrojetową podczas łączenia metodami spawalniczymi elementów nośnych koparko-ładowarek. Chłodzenie umożliwia sterowanie strukturą spoiny, dzięki czemu parametry gotowego złącza są dobrane precyzyjnie do potrzeb. Przeanalizowana została problematyka budowy i napraw koparko-ładowarek oraz zaprezentowano stanowisko spawalnicze, pozwalające na badanie metody mikrojetowej.This article analyzes usage of microjet cooling during weld joining of digger/loaders’ body elements. Cooling enables controlling structure of a juncture, what results in a weld adjusted perfectly to the needs. The analysis contains the issue of constructing and repairing digger/loaders and the description of a workplace where the microjet method may be examined
Implementing of the new ecodesign requirements of IEC and of the European Community in the home production of induction motors
The new standards of IEC defining four efficiency classes of induction motors and the respective regulations of the European Union are presented. The dependence of the material costs on the expected efficiency is analyzed by means of the optimization procedure. The economical effects which result from implementing the new regulations for the users and for the manufacturers are evaluated. Some details of the new regulations of the European Union are criticized
On equitable approaches to resource allocation problems: the conditional minimax solutions
In this paper we introduce and analyze a solution concept of the conditional minimax as a generalization of the minimax solution concept extended to take into account the number of services (the portion of demand) related to the worst performances. Namely, for a specified portion of demand we take into account the corresponding portion of the maximum results and we consider their average as the worst conditional mean to be minimized. We show that, similar to the standard minimax approach, the minimization of the worst conditional mean can be defined by a linear objective and a number of auxiliary linear inequalities. We report some results of initial computational experience with the new solution concept
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