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671.
Naeem Jan Abdul Nasir Mohsin S. Alhilal Sami Ullah Khan Dragan Pamucar Abdulrahman Alothaim 《Entropy (Basel, Switzerland)》2021,23(9)
Recently, there has been enormous development due to advancements in technology. Industries and enterprises are moving towards a digital system, and the oil and gas industries are no exception. There are several threats and risks in digital systems, which are controlled through cyber-security. For the first time in the theory of fuzzy sets, this research analyzes the relationships between cyber-security and cyber-crimes in the oil and gas sectors. The novel concepts of complex intuitionistic fuzzy relations (CIFRs) are introduced. Moreover, the types of CIFRs are defined and their properties are discussed. In addition, an application is presented that uses the Hasse diagram to make a decision regarding the most suitable cyber-security techniques to implement in an industry. Furthermore, the omnipotence of the proposed methods is explained by a comparative study. 相似文献
672.
Jari Tamminen Erkki Kolehmainen Juha Linnanto Pirjo Vainiotalo Sami Vuorikoski Reijo Kauppinen 《Journal of inclusion phenomena and macrocyclic chemistry》2000,37(1-4):121-130
Lithocholic acid N-(2-aminoethyl)amide (1) and deoxycholic acid N-(2-aminoethyl)amide(2) have been prepared and characterized by1H, 13C and 15N NMR. The accurate molecular masses of 1 and 2 have been determined by ESI MS. The formation of the Cd2+-complexes (1+Cd and 2+Cd) in CD3OD solution have been detected by 1H,13C, 15N and 113Cd NMR. The 13C NMR chemical shift assignments of 1 and 2 and their Cd2+-complexes are based on DEPT-135 and z-GS 1H,13C HMQC experiments as well as comparison with the assignments of the related structures. The 15N NMR chemical shiftassignments of the ligands and theirCd2+-complexes are based on z-GS1H,15N HMBC experiments. 13C NMR chemical shift differences between 1and its 1:1 Cd2+-complex based on ab initiocalculations at Hartree-Fock SCI-PCM level using3-21G(d) basis set are in agreement with theexperimental shift changes observed onCd2+-complexation. 相似文献
673.
Gautham Krishnamoorthy Muhammad Sami Stefano Orsino Anura Perera Mehrdad Shahnam E. David Huckaby 《International Journal of Computational Fluid Dynamics》2013,27(3-4):69-82
Coal combustion was simulated in a lab-scale furnace and a full scale utility boiler at air-burn, oxy-combustion with dry- and wet-flue gas recycles. Good agreement was obtained between the numerical predictions and experimental measurements. The study confirmed that certain dry and wet recycle ratios imitate the temperature and heat transfer characteristics found in air combustion. The performances of five grey models to predict the radiative properties of gases in the simulations were examined. Emissivity correlations developed for purely CO2 media were not found to be suitable to predict the property at low H2O/CO2 ratios encountered during dry-recycle. Therefore, a new total emissivity correlation and a weighted-sum-of-grey-gases (WSGG) model were formulated to address the shortcomings and inaccuracies in existing grey gas models under oxy-firing. The new WSGG model with 4 band intervals was found to perform well in test cases that were representative of air- and oxy-firing conditions in boilers. 相似文献
674.
The present study examines the entropy generation during cooling and heating cycles of repetitive pulsed-laser heating. Two repetitive pulses are introduced in the analysis. The possible thermal integration occurring at the workpiece surface due to repetitive pulse heating is then related to the second-law efficiency of the heating process. It is found that the cooling periods and low intensity decay rate result in a low total entropy generation number. The optimal cooling period satisfying the condition for the thermal integration does not result in the highest second law efficiency. 相似文献
675.
Alila S Boufi S Belgacem MN Beneventi D 《Langmuir : the ACS journal of surfaces and colloids》2005,21(18):8106-8113
The adsorption of four cationic surfactants with different alkyl chain lengths on cellulose substrates was investigated. Cellulose fibers were used as model substrates, and primary alcohol groups of cellulose glycosyl units were oxidized into carboxylic groups to obtain substrates with different surface charges. The amount of surfactant adsorbed on the fiber surface, the fiber zeta-potential, and the amount of surfactant counterions (Cl(-)) released into solution were measured as a function of the surfactant bulk concentration, its molecular structure, the substrate surface charge, and the ionic strength. The contribution of each of these parameters to the shape of the adsorption isotherms was used to verify if surfactant adsorption and self-assembly models usually used to describe the behavior of surfactant/oxide systems can be applied, and with which limitations, to describe cationic surfactant adsorption onto oppositely charged cellulose substrates. 相似文献
676.
Sikanen T Tuomikoski S Ketola RA Kostiainen R Franssila S Kotiaho T 《Lab on a chip》2005,5(8):888-896
The characterization of SU-8 microchannels for electrokinetic microfluidic applications is reported. The electroosmotic (EO) mobility in SU-8 microchannels was determined with respect to pH and ionic strength by the current monitoring method. Extensive electroosmotic flow (EOF), equal to that for glass microchannels, was observed at pH > or =4. The highest EO mobility was detected at pH > or =7 and was of the order of 5.8 x 10(-4) cm(2) V(-1) s(-1) in 10 mM phosphate buffer. At pH < or =3 the electroosmotic flow was shown to reverse towards the anode and to reach a magnitude of 1.8 x 10(-4) cm(2) V(-1) s(-1) in 10 mM phosphate buffer (pH 2). Also the zeta-potential on the SU-8 surface was determined, employing lithographically defined SU-8 microparticles for which a similar pH dependence was observed. SU-8 microchannels were shown to perform repeateably from day to day and no aging effects were observed in long-term use. 相似文献
677.
Sami I. Muslih 《Czechoslovak Journal of Physics》2003,53(12):1163-1171
We investigate the path-integral quantization of constrained systems with second-order Lagrangians using the Hamilton-Jacobi method. The path-integral quantization for two models is obtained using the canonical path-integral method. 相似文献
678.
The construction of a laser-based Raman scattering system for identifying major gas species and quantifying their partial pressures is described. The system incorporates a pulsed laser to minimize the background luminescence. The results obtained at room temperature for N2 at (365·80·5) nm and for O2 at (355·80·5) nm are presented. 相似文献
679.
Sami Sayadi Fathi Zorgani Radhouane Ellouz 《Applied biochemistry and biotechnology》1996,56(3):265-276
This paper describes the decolorization and chemical oxygen demand (COD) removal of olive mill waste-waters (OMW) byPhanerochaete chrysosporium grown in agitated submerged cultures. WhenP. chrysosporium was cultivated in the form of pellet, no decolorization of crude OMW was observed. Decolorization occured only after removing by ultrafiltration, the high-mol-wt (HM) polyphenolic fraction (> 60 kDa). The use of high lignin peroxidase (LiP) producing medium yielded the highest levels of OMW decolorization and COD removal. In this case, extensive depolymerization and subsequent accumulation of phenolics with intermediates molecular weight were observed. Furthermore, increasing the concentration of the HM fraction decreased the color and COD removals. The decolorizing activity was lost when the concentration of the HM fraction reached 25% (v/v). Consequently, LiP activity was found to be completely inhibited in the presence of HM fraction, but not with the low-mol-wt (LM) polyphenolic fraction (<8 kDa). The use ofP. chrysosporium immobilized on polyurethane foam resulted in efficient decolorization of crude OMW. Moreover, the addition of an induction medium was shown to perform several repeated batch cultures for OMW decolorization and COD removal. 相似文献
680.
Bisfunctionalized Janus molecules 总被引:1,自引:0,他引:1
[reaction: see text] Bisfunctionalized dendritic multiester molecules were synthesized by combined protection-deprotection and divergent-convergent-divergent sequences in high yields leading to dendritic molecules that combine two functionally different surfaces, polar aliphatic arborol and nonpolar gallate ether moieties, resulting in a two-faced Janus molecule. 相似文献