Investigations of the Structure of the Diurnal Variations of Geomagnetic Field

Changes in solar activity mechanisms generate changes in geomagnetic activity. The structure of geomagnetic activity can be illustrated by classes of the periodic and non-periodic variations of geomagnetic field. This study shows the results of the analysis of the periodic and non-periodic diurnal variations in the geomagnetic field (variations Sq, Sd,) and disturbances of geomagnetic activity (variations of indices Ri, Kp). The analysis was carried out during the months in which extreme solar and geomagnetic storms were recorded, October 2003 and November 2004. An analysis the structure and morphology of diurnal variations was made on the basis of the recorded geomagnetic data (the mean hourly values of geomagnetic field, three-hour indices of geomagnetic activity), at the Geomagnetic Observatory Grocka (GCK) (Serbia).

Study of the optical power of nanophotonic soft contact lenses based on poly (2-hydroxyethyl methacrylate) and fullerene

U radu su predstavljeni rezultati komparativnih istraživanja optičke snage mekih kontaktnih sočiva (MKS) sa različitim tehnikama mjerenja koje se koriste pri finalnoj obradi kontaktnih sočiva. Tri vrste nanofotoničnih mekih kontaktnih sočiva su napravljene od standardnog polimacon materijala (Soleko SP38TM) sa inkorporiranim fulerenom C60, fulerolom C60(OH)24 i fuleren-metformin-hidroksilatom C60(OH)12(OC4N5H10)12. Za potrebe karakterizacije materijala za potencijalnu primjenu kod mekih kontaktnih sočiva, mjerena su optička svojstva mekih kontaktnih sočiva Rotleks i Nidek uređajem. Sa Rotleks uređajem dobijeni su sledeći optički rezultati: optička snaga i mapa defekata, a sa Nidek uređajem: optička snaga, snaga cilindra i ugao cilindra. Dobijene vrijednosti optičke snage i mape defekata pokazali su da optička snaga sintetisanih nanofotoničnih mekih kontaktnih sočiva je identična nominalnoj vrijednosti, dok to nije bio slučaj za standardna meka kontaktna sočiva. Takođe, kvalitet nanofotoničnih mekih kontaktnih sočiva je bolji nego kod standardnih mekih kontaktnih sočiva. Iz prikazanog se može zaključiti da je moguće sintetisati nova nanofotonična meka kontaktna sočiva željenih optičkih karakteristika, što otvara mogućnosti za njihovu primjenu u ovoj oblasti.In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38 TM) incorporated with fullerene C 60 , fullerol C 60 (OH) 24 and fullerene metformin hydroxylate C 60 (OH) 12 (OC 4 N 5 H 10) 12. For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field

Magnetic Storms and their Influence on navigation

U radu se prikazuju karakteristike Sunčevih i Zemljinih magnetskih polja, njihova međusobna povezanost, ali i njihove anomalije. Broj Sunčevih pjega, koje se povećavaju i smanjuju u nejednakim ciklusima, odgovara broju registriranih magnetskih oluja na Zemlji. Sunčeve plazma-zrake koje izbijaju iz Sunčevih pjega uzrokuju porast broja solarnih vjetrova i pri tome utječu na geomagmetsko polje i Zemljinu atmosferu. Jedan primjer takve uzročne veze bila je najžešća magnetska oluja koja se pojavila u tijeku posljednja dva Sunčeva ciklusa. Trajala je od 28. listopada do 02. studenoga 2003. godine. Uspješna plovidba ovisi o uzimanju u obzir svih promjena na Zemlji koje nastaju zbog promjena na Suncu.This article presents the nature of the Sun’s and Earth’s magnetic fields, their mutual connection and anomalies. The number of sunspots, that increase and decrease in unequal cycles, correspond to the number of registered magnetic storms on the Earth. The Sun’s plasma streams that shoot out from the sunspots cause an increase in the solar winds and in doing so they affect the geomagnetic field and the Earth’s atmosphere. One example of such a causal connection was the most extreme magnetic storm that has occurred during the last two Sun Cycles. It lasted from October 28th to November 2nd 2003. Successful navigation depends on taking into consideration all the changes on the Earth that arises from changes on the Sun

The Structure of the Big Magnetic Storms

The records of geomagnetic activity during Solar Cycles 22 and 23 (which occurred from 1986 to 2006) indicate several extremely intensive A-class geomagnetic storms. These were storms classified in the category of the Big Magnetic Storms. In a year of maximum solar activity during Solar Cycle 23, or more precisely, during a phase designated as a post-maximum phase in solar activity (PPM – Phase Post maximum), near the autumn equinox, on 29, October 2003, an extremely strong and intensive magnetic storm was recorded. In the first half of November 2004 (7, November 2004) an intensive magnetic storm was recorded (the Class Big Magnetic Storm). The level of geomagnetic field variations which were recorded for the selected Big Magnetic Storms, was ΔDst > 350 nT. For the Big Magnetic Storms the indicated three-hour interval indices geomagnetic activity was Kp = 9. This study presents the spectral composition of the Di – variations which were recorded during magnetic storms in October 2003 and November 2004

Study of the optical power of nanophotonic soft contact lenses based on poly (2- hydroxyethyl methacrylate) and fullerene

In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38TM) incorporated with fullerene C60, fullerol C60(OH)24 and fullerene metformin hydroxylate C60(OH)12(OC4N5H10)12.For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field.In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38TM) incorporated with fullerene C60, fullerol C60(OH)24 and fullerene metformin hydroxylate C60(OH)12(OC4N5H10)12.For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field

Remanent Magnetization Measurements of the Fullerene Thin Films

Magnetic properties of carbon vary according to its allotropic modifications. Although carbon atom is known as a diamagnetic, some distinctive features point out that its magnetic properties are not that simple. Fullerene C-60, a carbon atoms molecule, is proven to have very different magnetizations than other forms of carbon compounds. Rhombohedral fullerene is shown to have ferromagnetic properties, and thus investigations of fullerene as a magnetic material are necessary. Fullerene C-60 in the form of thin film is also shown to have distinctive magnetic properties. In this paper, remanent magnetization of fullerene thin films, thicknesses of 100 and 250 nm were investigated when films are in the dark and exposed to polarized light. Research showed how light is influencing the material and its magnetization

Remanent Magnetization Measurements of the Fullerene Thin Films

Magnetic properties of carbon vary according to its allotropic modifications. Although carbon atom is known as a diamagnetic, some distinctive features point out that its magnetic properties are not that simple. Fullerene C-60, a carbon atoms molecule, is proven to have very different magnetizations than other forms of carbon compounds. Rhombohedral fullerene is shown to have ferromagnetic properties, and thus investigations of fullerene as a magnetic material are necessary. Fullerene C-60 in the form of thin film is also shown to have distinctive magnetic properties. In this paper, remanent magnetization of fullerene thin films, thicknesses of 100 and 250 nm were investigated when films are in the dark and exposed to polarized light. Research showed how light is influencing the material and its magnetization