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1

Carboxymethyl Cellulose Nanoadsorbent for Remediation of Polluted Water

Khairiah Khairiah, Frida Erna, Sebayang Kerista, Sinuhaji Perdinan, Humaidi Syahrul, Ridwanto, Fudholi Ahmad, Marwoto Putut

Journal of Ecological Engineering

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2023

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Vol. 24, nr 1

336--348

EN

The development of nanoadsorbents for remediation of polluted water in order to obtain clean and healthy water quality has been carried out, namely the incorporation of chitosan, magnetic, and activated carbon materials. The activated carbon used is the result of the synthesis of banana peel waste nanocrystals, while the magnetic is Fe3O4. The method used in this study is an experimental method with coprecipitation through several stages, namely (1) magnetic synthesis of Fe3O4 by thecoprecipitation method, (2) preparation of chitosan solution, (3) synthesis of activated carbon nanocrystals from banana peel waste by the milling process, (4) merger of the three materials, and (5) characterization with SEM/EDX, XRD, FTIR, BET, PSA, TGA, and AAS to test the performance of the material against polluted water. The study found that 210 minutes was the optimal time for the heavy metal ions Fe, Mn, Zn, and Pb to adsorption.The best sample was sample S4 with a ratio of 1:2:2 with adsorption for Zn 92.43%, Fe 95.44%, Mn 89.54%, and Pb 84.38%. For the heavy metal ions: Mn 5624 mg/g, Fe 5849.4 mg/g, Zn 4894.22 mg/g, and Pb 468.2 mg/g, the Langmuir model was used. The adsorption kinetics showed that the reaction order for Pb, Mn, Zn, and Fe ions varied with pseudo-first order and pseudo-second order. Carboxymethyl cellulose nanoadsorbents are effective in remediating the water contaminated with heavy metals, such as Pb, Mn, Zn, and Fe, meeting the environmental health quality standards for water media for sanitation hygiene purposes.

2

Comparison of sorption capacity of biochar-based sorbents for capturing heavy-metallic ions from water media

Bąk Justyna

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 150265

EN

To develop the sorption efficiency of heavy metals: Cd(II), Co(II), Zn(II) and Pb(II) ions the biochar was modified by chitosan, FeSO4 and NaBH4. The morphology, physical structure and chemical composition of the biochar based sorbents were characterized by the scanning electron miscroscopy method, N2 adsorption and desorption isotherms, X-ray diffractometry as well as the Fourier transform infrared spectroscopywith the attenuated total reflectance analyses. The research of M(II) ions sorption was carried out as a function of pH (2-6), interaction time (0-360 minutes) and temperature (293, 313, 333 K). The maximum sorption was obtained by the ChBC for Zn(II) ions - 19.23 mg/g and for MBC-Pb(II) - 19.11 mg/g. Different kinetic models as well as both isotherm and thermodynamic equations were used the sorption data modelling. For Cd(II), Co(II) and Zn(II) ions the nonlinear regression of the Elovich equation gave the best fit for the experimental data. On the other hand, for Pb(II) ions, the nonlinear forms of pseudo first order and pseudo second order show a better match. The value of the correlation coefficient >0.960 determined from the Freundlich isotherm model is the highest suggesting a good fit to the experimental data. The thermodynamic parameters: ΔG°, ΔH° and ΔS° were listed and indicated that the process is spontaneous and endothermic in nature. The desorption efficiency was determined with the use of nitric, hydrochloric and sulfuric acids and the largest desorption yield for Pb(II)-ChBC equal 99.5 % was gained applying HNO3.

3

High Efficient Photocatalytic Degradation of Methyl Orange Dye in an Aqueous Solution by CoFe2O4-SiO2-TiO2 Magnetic Catalyst

Hariani Poedji Loekitowati, Said Muhammad, Salni, Aprianti Nabila, Naibaho Yohanna Asina Lasma Rohana

Journal of Ecological Engineering

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2022

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Vol. 23, nr 1

118--128

EN

This study successfully synthesized a core-shell-shell in the form of CoFe2O4-SiO2-TiO2 catalyst magnetic and recyclable. The catalyst was employed for the photocatalytic degradation of methyl orange (MO) dye. Subsequently, the catalyst was subjected to XRD, FTIR, SEM-EDS, VSM, as well as UV-DRS characterizations. The photocatalytic degradation was studied as a function of the solution pH, MO concentration, and irradiation time, while the kinetics of photocatalytic degradation and the catalyst reusability were also evaluated. On the basis of the XRD, FTIR, and SEM-EDS characterizations, the CoFe2O4 coating was successfully carried out using SiO2 and TiO2. CoFe2O4-SiO2-TiO2 was discovered to possess magnetic properties with a saturation magnetization of 17.59 emu/g and a bandgap value of 2.4 eV. The photocatalytic degradation of MO followed the Langmuir-Hishelwood model. The optimum degradation was obtained at the MO concentration of 25 mg/L, solution pH of 4, catalyst dose of 0.05 g/L, irradiation time of 160 minutes, MO removal efficiency achieved 93.46%. The regeneration study showed CoFe2O4-SiO2-TiO2 after 5 cycles were able to catalyze the photocatalytic degradation with an MO removal efficiency of 89.96%.

4

Experimental investigation of the electrochemical micromachining process of Ti-6Al-4V titanium alloy under the influence of magnetic field

Gopinath T. Praveena, Prasanna J., Sastry C. Chandrasekhara, Patil Sandeep

Materials Science Poland

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2021

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Vol. 39, No. 1

124--138

EN

An attempt has been made to study the influence of magnetic field on the micro hole machining of Ti-6Al-4V titanium alloy using electrochemical micromachining (ECMM) process. The presence of magneto hydro dynamics (MHD) is accomplished with the aid of external magnetic field (neodymium magnets) in order to improve the machining accuracy and the performance characteristics of ECMM. Close to ideal solution for magnetic and nonmagnetic field ECMM process, the parameters used are as follows: concentration electrolyte of 15 g/l; peak current of 1.35 A; pulse on time of 400 s; and duty factor of 0.5. An improvement of 11.91–52.43% and 23.51–129.68% in material removal rate (MRR) and 6.03–21.47% and 18.32–33.09% in overcut (OC) is observed in ECMM of titanium alloy under the influence of attraction and repulsion magnetic field, respectively, in correlation with nonmagnetic field ECMM process. A 55.34% surface roughness factor reduction is ascertained in the hole profile in magnetic field-ECMM in correlation with electrochemical machined titanium alloy under nonmagnetic field environment. No machining related stress is induced in the titanium alloy, even though environment of electrochemical machining process has been enhanced with the presence of magnetic field. A slight surge in the compressive residual factor, aids in surge of passivation potential of titanium alloy, resulting in higher resistance to outside environment.

5

Solvent-free synthesis of 1-amidoalkyl-2-naphthol and 3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile derivatives by Fe3O4@enamine-B(OSO3H)2 as an efficient and novel heterogeneous magnetic nanostructure catalyst

Li Fangping, Zhang Jun, Wang Longjiang, Liu Weijian, Yousif Qahtan A.

Polish Journal of Chemical Technology

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2020

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Vol. 22, nr 2

9--19

EN

A green procedure for the one-pot three-component synthesis of 1-amidoalkyl-2-naphthol and 3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile derivatives from the reaction of 2-naphtol, aldehydes, and malononitrile/acetamide in the presence of a catalytic amount of Fe3O4@enamine-B(OSO3H)2 as an efficient and novel heterogeneous magnetic nanostructure catalyst is described. The catalyst was characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). These strategies possess some merits such as simple work-up method, easy preparation of the catalyst, short reaction times, good-to-high yields, and non-use of hazardous solvents during all steps of the reactions. Moreover, due to the magnetic nature of the catalyst, it was readily recovered by magnetic decantation and can be recycled at least six runs with no considerable decrease in catalytic activity.

6

Modeling the inspection robot with magnetic pressure pad

Kurc Krzysztof, Burghardt Andrzej, Szybicki Dariusz, Giergiel Józef

Mechanics and Mechanical Engineering

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2019

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Vol. 23, nr 1

50--58

EN

This article presents the process of designing a robot with a magnetic pressure pad for inspections of ferromagnetic ventilation ducts. In compliance with the assumptions, the CAD design of the robot was developed in a 3D programming environment. The designing proces brought about a mathematical model of the robot with one pair of magnetic drive modules, including simulation in a MATLAB/Simulink environment. The model accounted for parameters such as rolling resistance force, transverse resistance moment, magnetic attraction force, solid moment of inertia, and other factors. The magnetic pressure pad allowed for moving the robot in magnetic ventilation systems irrespective of slopes and shapes of ducts.

7

Signals parametrization method of sailing vessels

Buszman K., Gloza I.

Hydroacoustics

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2016

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Vol. 19

27--36

EN

The expansion of maritime transport is directly connected with increased risk of the appearance of unidentified vessels in the approaches to ports, wind farms, and other sensitive places in the water-body. Creating a parameters database of sailing objects, based on recorded dynamic variations of different physical fields with the specified aims of increasing security within the strategic offshore areas.

8

Recent simulation results of the magnetic induction tomography forward problem

Stawicki K., Szuflitowska B., Ziolkowski M.

Archives of Electrical Engineering

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2016

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Vol. 65, nr 2

327--336

EN

In this paper we present the results of simulations of the Magnetic Induction Tomography (MIT) forward problem. Two complementary calculation techniques have been implemented and coupled, namely: the finite element method (applied in commercial software Comsol Multiphysics) and the second, algebraic manipulations on basic relationships of electromagnetism in Matlab. The developed combination saves a lot of time and makes a better use of the available computer resources.

9

Structural Investigations of Afghanistan Deduced from Remote Sensing and Potential Field Data

Saibi H., Azizi M., Mogren S.

Acta Geophysica

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2016

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Vol. 64, no. 4

978--1003

EN

This study integrates potential gravity and magnetic field data with remotely sensed images and geological data in an effort to understand the subsurface major geological structures in Afghanistan. Integrated analysis of Landsat SRTM data was applied for extraction of geological lineaments. The potential field data were analyzed using gradient interpretation techniques, such as analytic signal (AS), tilt derivative (TDR), horizontal gradient of the tilt derivative (HG-TDR), Euler Deconvolution (ED) and power spectrum methods, and results were correlated with known geological structures. The analysis of remote sensing data and potential field data reveals the regional geological structural characteristics of Afghanistan. The power spectrum analysis of magnetic and gravity data suggests shallow basement rocks at around 1 to 1.5 km depth. The results of TDR of potential field data are in agreement with the location of the major regional fault structures and also the location of the basins and swells, except in the Helmand region (SW Afghanistan) where many high potential field anomalies are observed and attributed to batholiths and near-surface volcanic rocks intrusions. A high-resolution airborne geophysical survey in the data sparse region of eastern Afghanistan is recommended in order to have a complete image of the potential field anomalies.

10

Evolutionary Algorithm for Particle Trajectory Reconstruction within Inhomogeneous Magnetic Field in the NA61/SHINE Experiment at CERN SPS

Wyszyński O.

Schedae Informaticae

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2015

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Vol. 24

159--177

EN

In this paper, a novel probabilistic tracking method is proposed. It combines two competing models: (i) a discriminative one for background classification; and (ii) a generative one as a track model. The model competition, along with a combinatorial data association, shows good signal and background noise separation. Furthermore, a stochastic and derivative-free method is used for parameter optimization by means of the Covariance Matrix Adaptation Evolutionary Strategy (CMA-ES). Finally, the applicability and performance of the particle trajectories reconstruction are shown. The algorithm is developed for NA61/SHINE data reconstruction purpose and therefore the method was tested on simulation data of the NA61/SHINE experiment.

11

Synthesis and characterization of graphene oxide composite with Fe3O4

Sun C., Wang Y.

Materials Science Poland

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2015

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Vol. 33, No. 3

488--490

EN

In the paper, a magnetic composite of graphene oxide (MGO) has been successfully synthesized through decomposition of iron (III) acetylacetonate in the mixture solution of triethylene glycol and graphene oxide (GO). Atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and superconducting quantum interference device were used to characterize the material. The results show that the magnetic Fe3O4 nanoparticles modified graphene oxide composite with superparamagnetic properties, and magnetization saturation of 16.4 emu/g has been obtained. The MGO has a good sustained-release performance, and in vitro cytotoxicity confirming its secure use as a potential drug carrier.

12

A comparison between cylindrical and cross-shaped magnetic vibration isolators: ideal and practical

Van Casteren D.T.E.H., Paulides J.J.H., Lomonova E.A.

Archives of Electrical Engineering

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2015

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Vol. 64, nr 4

593--604

EN

In this paper a cross-shaped isolator consisting of cuboidal magnets and a cylindrical isolator are compared by resonance frequency to volume ratio and shape. Both isolators are capable of obtaining a low resonance frequency, i.e. 0.15 Hz and 0.01 Hz for the cross and cylinder, respectively. The volume of both isolators is comparable, only the shape is different, resulting in a tall structure with a small footprint for the cross and a flat with a large diameter cylindrical structure. A sensitivity analysis shows that due to the large amount of magnets, the cross-shaped isolator is less sensitive to manufacturing tolerances.

13

Ising Model Phase Transition Calculation for Ferro-Paramagnetic Lattice

Khudier D. K., Fawaz N. I.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 10, iss. 2

201-212

EN

The position of the phase transition in the two dimensional Ising model were determined by using Monte Carlo simulation in a quadratic for area of variable length with external magnetic field switched off (B = 0). The magnetization per site , magnetic susceptibility of a ferromagnetic and paramagnetic materials were calculated as a function of temperature for , spin lattice interactions. Nearest neighbor interaction is assumed (i.e. each spin has 4 neighbors); uses periodic boundary conditions. The Curie temperature is determined by measuring the magnetic susceptibility at which the ferromagnetic and paramagnetic undergoes a phase change from order to disorder. There is thus a phase transition defined by the Curie temperature. The Monte Carlo method were used to check these results and to confirm the phase transition. The data are analyzed using the Curie-Weiss law which contains the Curie temperature as a parameter.

14

Bezprzewodowy system detekcji magnetycznej

Studziński J.

Zeszyty Naukowo-Techniczne Stowarzyszenia Inżynierów i Techników Komunikacji w Krakowie. Seria: Materiały Konferencyjne

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2009

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Nr 89, z. 146

187-193

PL

System Bezprzewodowej Detekcji Pojazdów wykorzystuje zamontowane pod powierzchnią ziemi sensory magnetyczne do wykrywania obecności pojazdów. Sensory przekazują informację o pojazdach drogą radiową do odbiornika, który z kolei przesyła tą informację do sterownika ruchu drogowego. Jeżeli sensory znajdują się poza zasięgiem odbiornika, stosuje się wzmacniacz, który będzie pośredniczył w przekazywaniu informacji od sensora. System Detekcji Magnetycznej jest alternatywą dla powszechnie stosowanych innych rodzajów detekcji takich jak pętle indukcyjne lub Wideodetekcja.

EN

Wireless Magnetic Detection System uses the pavement-mounted magnetic sensors to detect the presence and the movement of vehicles. The magneto-resistive sensors are wireless, transmitting their detection data in real-time via low-power radio technology to a nearby Access Point (or Repeater) that then relays the data to one or more local or remote traffic management controllers and systems. Wireless Magnetic Detection System can be used as an alternative for the cameras or the inductive loops.

15

Sposoby przekłamywania wskazań tachografu cyfrowego

Rychter M.

Logistyka

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2009

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nr 6

CD-CD

PL

Z powodu jego natury, system cyfrowych tachografów będzie przedmiotem wszelkich manipulacji. Wszystkie systemy tachografów posiadają liczne sposoby ochrony, były są i będą przedmiotem poddawania wszelkiego rodzaju ingerencji. Zabiegami przeznaczonymi w celu rejestracji krótszej przejechanej drogi i prędkości.

EN

On account of his nature, the system of digital tachographs he will be an object exposed to manipulations. All systems of tachographs own numerous securities, they are and they will be surrendered of different kind for interferences, being aimed distorting data registered by them.

16

The distribution of magnetic fields and an analysis of the separation in process in a spiral separater

Brożek M.

Archives of Mining Sciences

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2002

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Vol. 47, nr 2

139-156

EN

In the magnetic separation of strongly magnetic, fine-grained minerals the forces of magnetic and surface interaction between particles play a significant role. These forces lead to the phenomenon of magnetic flocculation. Non-magnetic particles are held in the floe volume and these, transfered to the magnetic products, lower the quality of concentrate. In order to reduce the effects of this phenomenon, special separators with an alternating magnetic field have been constructed or, the movement of the particulate mixture through the a constant magnetic field, a system of pole shoes of alternate polarity is employed. In the latter type of separators the particles of the aggregates are subjected to several magnetization cycles, in the course of which the non-magnetic components are precipitated. A spiral separater is a separation system using a series of magnetic fields with constant polarity. The paper discusses the principles of operation of this type of separater and determines the distribution of the magnetic fields and magnetic force in the separator's working space by means of conformal mapping. Following this the value of separation magnetic susceptibility was calculated from the balance of external forces acting on the particle. Applying the stochastic model of magnetic separation, the author has evolved an expression for a constant rate of separation and content of magnetic component in the concentrate, the yield of the concentrate as a function of the angle of inclination of the separater, the amount of washing water supplied, the number of helix rotations and the intensity of the external magnetic field. The dependence of the Fc content in the concentrate on the amount of washing water was verified experimentally. It was observed that surface interactions between particles should be taken into consideration when a full correlation between the model and experimental values is required.

PL

Przy separacji magnetycznej drobnoziarnistych minerałów silnie magnetycznych istotną rolą odgrywają siły oddziaływań magnetycznych i powierzchniowych między ziarnami. Siły te prowadzą do zjawiska flokulacji magnetycznej. W objętości flokuly mechanicznie zatrzymywane są ziarna niemagnetyczne, które wynoszone do produktu magnetycznego pogarszają jakość koncentratu. Aby usunąć skutki tego zjawiska konstruuje się separatory ze zmiennym polem magnetycznym lub na drodze ruchu mieszaniny ziarn stosuje się stałe pole magnetyczne z układem nabiegunników o naprzemiennej biegunowości. W takich separatorach agregaty ziarnowe ulegają kilkakrotnym przemag-nesowaniom, w trakcie których tracą ziarna niemagnetyczne. Jednym z separatorów o stałym polu magnetycznym jest separator zwojowy (spiralny). W pracy omówiono zasadę działania separatora oraz metodą odwzorowań konforemnych wyznaczono rozkład pola magnetycznego i siły magnetycznej w przestrzeni roboczej separatora, a następnie z bilansu sił zewnętrznych działających na ziarno mieszaniny wyliczono wartość podatności magnetycznej podziałowej. Posługując się stochastycznym modelem separacji magnetycznej przedstawiono wyrażenia na właściwą prędkość separacji oraz zawartość składnika magnetycznego w koncentracie i wychód koncentratu w funkcji kąta nachylenia koryta separatora, ilości wody spłukującej, liczby obrotów ślimaka oraz natężenia zewnętrznego pola magnetycznego. Eksperymentalnie zweryfikowano zależność zawartości żelaza w koncentracie od ilości wody spłukującej. Zauważono, że chcąc uzyskać pełną zgodność modelu z doświadczeniem należy uwzględniać oddziaływania powierzchniowe między ziarnami.

17

Synthetic, structural, thermal and Electrical Properties of Some Transition metal Polymeric Chelatres of Bis(mercaptoacetamido)diaminobutane

Mohod R.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 9

1229-1235

EN

Polymeric chelates of bis(mercaptoacetamido)-1,4-diaminobutane (BMADB) with manganese( II), cobalt(II), nickel(II), copper(II), zinc(II) and cadmium(II) ions have been synthesized and characterized by elemental analysis, magnetic moment, infrared, electronic spectra and thermal analysis. In the present investigation the ligand BMADB exhibits bis-bidentate character and coordinates symmetrically with metal through nitrogen of amido and sulfur of mercapto groups. The thermogravimetric studies indicate a two stage decomposition and the presence of water molecules. Thermal data have been analyzed by Freeman-Carroll and Sharp-Wentworth methods and various kinetic and thermodynamic parameters have also been evaluated. Comparable values of parameters indicate common decomposition reaction mode in all chelates. Their d.c. electrical conductivity in pellet form over a wide range of temperatures have also been studied.