Determination of Magnetic Exchange Stiffness and Surface Anisotropy Constants in Epitaxial Ni_ {1-x} Co_ {x}(001) Films

Magnetic characteristics of epitaxial Ni1-xCox(001) (x=0, 0.16, and 0.50) films with nominal 200 nm thickness on Cu(001)/Si(100) substrates have been investigated by magnetization and ferromagnetic resonance measurements in order to better clarify the rationale for the large variation in the magnetic exchange stiffness constant A, previously determined from different measurements. The exchange constant as well as the saturation magnetization, effective demagnetizing field, fourth-order magnetocrystalline, and second-order perpendicular uniaxial magnetic anisotropy fields has been determined. The analyses of low-temperature saturation magnetization data on these films yield A values that increase from 0.82×10-6erg/cm for a pure Ni film to 2.27×10-6erg/cm for the Ni0.50Co0.50 film. Furthermore, spin-wave resonance volume modes observed in x=0 and 0.16 films indicate that the surface plays a role in the exchange stiffness constant determination as the surface anisotropy constants are found to be approximately 1 and 4 erg/cm2, respectively. The latter value is substantially larger than that for any other system reported so far

Ferromagnetism at 300 K in spin-coated anatasea and rutile Ti0.95Fe0.05O2 films

Thin films of Ti1-xFexO2 (x=0 and 0.05) have been prepared on sapphire substrates by spin-on technique starting from metal organic precursors. When heat treated in air at 550 and 700 degrees C respectively, these films present pure anatase and rutile structures as shown both by X-ray diffraction and Raman spectroscopy. Optical absorption indicate a high degree of transparency in the visible region. Such films show a very small magnetic moment at 300 K. However, when the anatase and the rutile films are annealed in a vacuum of 1x10-5 Torr at 500 degrees C and 600 degrees C respectively, the magnetic moment, at 300 K, is strongly enhanced reaching 0.46 $\mu$B/Fe for the anatase sample and 0.48 $\mu$B/Fe for the rutile one. The ferromagnetic Curie temperature of these samples is above 350 K.Comment: 13 october 200

Data Privacy and Technological Ethics in Rural Area

In today's world of rapid increasing of technology, Data privacy and Ethics has become a major concern. The complexity of data and ethics poses incredible issues by collecting user personal information in digital world. the Digital service company usually bear responsibility of protecting users' personal data from unauthorized access however issue arise when service provider and platforms do not protect user collective data, and this led to data misuse and exposing sensible data of the person. To handling once data responsibly and ethically is important for safeguarding people's rights and preserving public trust. This study examines the ethical challenges in emerging technologies, including data privacy and ethics. The paper aims to provide awareness of data privacy and ethics in technology

Plants used by kamar, gond and halba tribe of Dhamtari district of Chhattisgarh for relief of sickle cell disease

In Chhattisgarh state sickle cell disease is reported in many tribal communities. Some of these tribes reside in Jawwara, Dugali, Nagari, Sihawa, which are the remote forest areas of Dhamtari. They totally dependent on forest and forest produce for their livelihood and ailments. Gond is the dominant tribe of C.G. as well as of India, Halba is an advance tribe and Kamar tribe is declared as one of the most primitive tribe of India in sixth five year plan. During Ethnobotanical survey it was observed that for cure ailments they used their traditional herbal medicines and use wild vegetables fruits and foods such as under ground rhizome of Curcuma angustifolia (Tikhur) fresh tuberous roots of Abelmoschus crinitus (Dotokand) flowers of Indigofera cassoides (Ghirgholi) and boiled seeds of Dolichos biflorus (Kulthi), unriped fruits of Carica papaya (Papita) and Musa paradisica (Kela) to improve their general health conditions. In traditional herbal medicines the whole plants as decoction of Andrographis paniculata. (Bhuineem) dried roots of Scoparia dulcies boiled, tubers of Dioscorea sps, dried powder of Chlorophytum tuberosum (Safed Musli) are used for general health problems. In the present study 20 sickle cell homozygous patients (identified during screening process of sickle cell project coordinated by Department of Biochemistry. Pt. Jawaharlal Nehru Memorial Medical College. Raipur, C.G.), are taken under consideration to check the level of fetal haemoglobin and haemoglobin after giving traditional herbal treatment by traditional medicine man for further six months because most of the health problems are managed by local traditional healers. After the stipulated time the fetal hemoglobin and hemoglobin status will be seen so as to see the role of traditional herbs taken by the tribal people.  Â

Measuring nanomechanical motion with an imprecision far below the standard quantum limit

We demonstrate a transducer of nanomechanical motion based on cavity enhanced optical near-fields capable of achieving a shot-noise limited imprecision more than 10 dB below the standard quantum limit (SQL). Residual background due to fundamental thermodynamical frequency fluctuations allows a total imprecision 3 dB below the SQL at room temperature (corresponding to 600 am/Hz^(1/2) in absolute units) and is known to reduce to negligible values for moderate cryogenic temperatures. The transducer operates deeply in the quantum backaction dominated regime, prerequisite for exploring quantum backaction, measurement-induced squeezing and accessing sub-SQL sensitivity using backaction evading techniques

Efficient absolute aspect determination of a balloon borne far infrared telescope using a solid state optical photometer

The observational and operational efficiency of the TIFR 1 meter balloon borne far infrared telescope has been improved by incorporating a multielement solid state optical photometer (SSOP) at the Cassegrain focus of the telescope. The SSOP is based on a 1-D linear photo diode array (PDA). The online and offline processing schemes of the PDA signals which have been developed, lead to improvement in the determination of absolute telescope aspect ($\sim$ 0\farcm8), which is very crucial for carrying out the observations as well as offline analysis. The SSOP and its performance during a recent balloon flight are presented here.Comment: To appear in the February 2000 issue of the PAS

Rotating Bose-Einstein Condensate Stars at finite temperature

We study the effect of temperature on the global properties of static and slowly rotating self-gravitating Bose-Einstein condensate (BEC) stars within general relativity. We employ a recently developed temperature dependent BEC equation of state (EoS) to describe the stellar matter by assuming that the condensate can be described by a non-relativistic EoS. Stellar profiles are obtained using general relativistic Hartle-Thorne slow rotation approximation equations. We find that with increasing temperatures mass-radius values are found to be decreasing for the static and rotating cases; though presence of temperature supports high mass values at lower central densities. Countering effects of rotation and temperature on the BEC stellar structure have been analysed and quantified. We report that inclusion of temperature has significant effect on the rotating stellar profiles but negligible effect on the maximum mass, as in the case of static system. We have also studied the effect of EoS parameters -- boson mass and strength of the self-interaction -- on global properties of static and rotating BEC stars, in presence of temperature.Comment: 12 pages, 10 figures; accepted for publication in Phys. Rev.