Parametrizacija funkcije raspodjele elektronske energije u tinjavom izboju u RF elektromagnetskom polju

A set of twenty four plasma glow discharge experiments using radio-frequency electromagnetic fields were carried out. The discharge pressure was 27 Pa. Dried air was used as the discharge gas. Axial radio-frequency fields between 0.6-1.2 MHz were applied. Four different values of the RF field intensity were used. For each case, the plasma Langmuir probe characteristics were measured. A computational method was used to extract the electron energy distribution function in each case. Values of the plasma density and plasma temperature were obtained directly from the fits. They compare well with values obtained using the conventional logarithmic method. The Maxwellian behaviour of the distribution function was established to hold in many but not in all cases.Izveli smo 24 mjerenja u plazmi u tinjavom izboju pod djelovanjem radiofrekventnog (RF) elektromagnetskog polja. Tlak u izboju bio je 27 Pa. Izbojni plin bio je suhi zrak. Rabili smo osna RF polja u području 0.6 do 1.2 MHz. Primijenili smo četiri jakosti RF polja. U svakom mjerenju odredili smo značajku Langmuirove probe. Računalnom smo metodom izveli funkciju elektronske raspodjele energije za svako mjerenje. Izravno iz prilagodbi izveli smo vrijednosti gustoć i temperature plazme. Te se vrijednosti dobro uspoređuu s vrijednostima dobivenim uobičajenom logaritamskom prilagodbom. Maxwellova funkcija raspodjele se pokazuje dobrom u mnogim, ali ne svim slučajevima

Parametrizacija funkcije raspodjele elektronske energije u tinjavom izboju u RF elektromagnetskom polju

A set of twenty four plasma glow discharge experiments using radio-frequency electromagnetic fields were carried out. The discharge pressure was 27 Pa. Dried air was used as the discharge gas. Axial radio-frequency fields between 0.6-1.2 MHz were applied. Four different values of the RF field intensity were used. For each case, the plasma Langmuir probe characteristics were measured. A computational method was used to extract the electron energy distribution function in each case. Values of the plasma density and plasma temperature were obtained directly from the fits. They compare well with values obtained using the conventional logarithmic method. The Maxwellian behaviour of the distribution function was established to hold in many but not in all cases.Izveli smo 24 mjerenja u plazmi u tinjavom izboju pod djelovanjem radiofrekventnog (RF) elektromagnetskog polja. Tlak u izboju bio je 27 Pa. Izbojni plin bio je suhi zrak. Rabili smo osna RF polja u području 0.6 do 1.2 MHz. Primijenili smo četiri jakosti RF polja. U svakom mjerenju odredili smo značajku Langmuirove probe. Računalnom smo metodom izveli funkciju elektronske raspodjele energije za svako mjerenje. Izravno iz prilagodbi izveli smo vrijednosti gustoć i temperature plazme. Te se vrijednosti dobro uspoređuu s vrijednostima dobivenim uobičajenom logaritamskom prilagodbom. Maxwellova funkcija raspodjele se pokazuje dobrom u mnogim, ali ne svim slučajevima

A Logarithmic Formula to Describe the Relationship between the Increased Radiosensitivity at Low Doses and the Survival at 2 Gray

Objectives: Intrinsic radiosensitivity at doses used in radiotherapy is linked to hypersensitivity (HRS) and increased radio resistance (IRR) at low doses. The aim of this study was to explore this relationship. Methods: Survival curves for 18 human tumour cell lines were analysed, using two models to fit the data points in order to extract the necessary parameters relevant for this study. Results: The IRR ratio αs/αr versus the survival at 2 gray (Gy) can be described by a logarithmic relation which leads to a series of straight lines. Conclusion: The relationship obtained implies that there is a direct link between HRS/IRR and survival at clinically relevant doses of 2 Gy

Evidence of Global Warming from Zakho Precipitation Data

Analysis of available precipitations data for Zakho area supports the argument that global warming has affected this region. Results shows that monthly and yearly rain fall have been decreasing systematically since the thirties of the last century until now. Based on linear correlation model, some future estimations of the reduction in precipitation as related to the global atmospheric carbon dioxide concentrations are made

Transgenic plants as green factories for vaccine production

Edible vaccine technology represents an alternative to fermentation based vaccine production system. Transgenic plants are used for the production of plant derived specific vaccines with native immunogenic properties stimulating both humoral and mucosal immune responses. Keeping in view the practical need of new technology for production and delivery of inexpensive vaccines, especially in developing world, plant derived edible vaccines is the best option in hand to combat infectious diseases. Plant derived vaccine is easy to administer, cost effective, readily acceptable, have increased safety, stability, versatility and efficacy. Several plant derived vaccines are under research, some are under clinical trials for commercial use. Like most  biotechnology products, the IP situation for edible vaccines is complex as IP rights influence every stage of vaccine development.Keywords: Transgenic plants, edible vaccines, chimeric viruses, bacterial diseases, viral diseases

Flat-gain wide-band erbium doped fiber amplifier by combining two difference doped fibers

A new erbium-doped fibre amplifier (EDFA) is demonstrated using a combination of newly developed Erbium Zirconia co-doped fiber (Zr-EDF) and the commercial silica-based Erbium-doped fiber (Si-EDF) as the gain medium. Both fibers have a very high concentration of erbium ion. A compact amplifier operating in C-band region is firstly reported using a double-pass configuration. It is shown that average gains of the proposed Zr-EDF amplifier are obtained at approximately 18 dB with a gain variation of ±2 dB within C-band region. A flat-gain and wide band operation is achieved by configuring the amplifier in two stages comprising a 2 m long Zr-EDF and 9 m long Si-EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region

Mode-locked thulium ytterbium co-doped fiber laser with graphene oxide paper saturable absorber

A mode-locked thulium ytterbium co-doped fiber laser (TYDFL) is proposed and demonstrated by using a commercial graphene oxide (GO) paper as saturable absorber (SA). The GO paper is sandwiched between two fiber ferrules and incorporates a ring laser cavity to generate soliton pulse train operating at 1942.0 nm at a threshold multimode pump power as low as 1.8 W. The mode-locked TYDFL has a repetition rate of 22.32 MHz and the calculated pulse width of 1.1 ns. Even though the SA has a low damage threshold, the easy fabrication of GO paper should promote its potential application in ultrafast photonics

Flat-gain wide-band erbium doped fiber amplifier by combining two difference doped fibers

A new erbium-doped fibre amplifier (EDFA) is demonstrated using a combination of newly developed Erbium Zirconia co-doped fiber (Zr-EDF) and the commercial silica-based Erbium-doped fiber (Si-EDF) as the gain medium. Both fibers have a very high concentration of erbium ion. A compact amplifier operating in C-band region is firstly reported using a double-pass configuration. It is shown that average gains of the proposed Zr-EDF amplifier are obtained at approximately 18 dB with a gain variation of +-2 dB within C-band region. A flat-gain and wide band operation is achieved by configuring the amplifier in two stages comprising a 2 m long Zr-EDF and 9 m long Si-EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength regio