Thin films with cobalt ferrite layers on thermally oxidized silicon wafers were fabricated by a sol-gel method. Magnetic and structural properties of the investigated an x-ray diffractometer, vibrating sample magnetometer atomic force microscopy. The crystallization temperature for Co thin was determined using Mössbauer spectroscopy. annealed at above 450 °C have only single phase spinel structure without any preferred crystallite orientation. Their rms surface roughness is less than 3 nm...

It has been reported that long working hours are hazardous to the workers' health. Especially, work-related musculoskeletal disorders (WMSDs) have considered as one of significant health issues in workplace. The objective this study was identify association between and symptoms.The analysis conducted using data from Fourth Korean Working Conditions Survey (KWCS). Subjects were 24,783 wage workers divided into three groups according weekly hours, which ≤ 40, 41-52 > 52 h. relationship...

Ultrafine Co0.9Mn0.1Fe2O4 particles are fabricated by a sol–gel method. Magnetic and structural properties of powders investigated with x-ray diffraction, vibrating samples magnetometer, Mössbauer spectroscopy. Co–Mn ferrite which were fired at above 673 K have only single phase spinel structure behave ferrimagnetically. Powders annealed typical the paramagnetic ferrimagnetic nature, simultaneously. The formation nanocrystallized is confirmed when 623 K. magnetic behavior 823 shows that an...

Nano-sized nickel substituted cobalt ferrite powders, <TEX>$Ni_xCo_{1-x}Fe_2O_4$</TEX> (<TEX>$0.0{\leq}x{\leq}1.0$</TEX>), were fabricated by the sol-gel method, and their crystallographic magnetic properties studied. All powders showed a single spinel structure, behaved ferrimagnetically. When substitution was increased, lattice constants sizes of particles decreased. The M<TEX>$\ddot{o}$</TEX>ssbauer absorption spectra could be fitted with two six-line subspectra, which assigned to...

Cr/sup 3+/ substituted Ba-hexaferrite was fabricated by a sol-gel method. The crystallographic and magnetic properties of BaFe/sub 12-x/Cr/sub x/O/sub 19/ (0/spl les/x/spl les/7) were investigated XRD, Rutherford backscattering spectrometry, vibrating sample magnetometry Mossbauer spectroscopy. crystal structure found to be magnetoplumbite, typical M-type hexagonal ferrite. By substituting Fe/sup in 12/O/sub 3+/, we have been able attribute the parameters 5 sites structure. Only octahedral...

The Zn, Co and Ni substituted manganese ferrite powders, <TEX>$Mn_{1-x}$</TEX>(Zn, Co, Ni)<TEX>$_xFe_2O_4$</TEX>, were fabricated by the solgel method, their crystallographic magnetic properties studied. Zn ferrite, <TEX>$Zn_{0.2}Mn_{0.8}Fe_2O_4$</TEX>, had a single spinel structure above <TEX>$400^{\circ}C$</TEX>, size of particles powder increased when annealing temperature was increased. Above <TEX>$500^{\circ}C$</TEX>, all Ni)<TEX>$_xFe_2O_4$</TEX> lattice constants decreased with an...

Nickel substituted manganese ferrites, <TEX>$Mn_{1-x}Ni_xFe_2O_4$</TEX> (<TEX>$0.0{\leq}x{\leq}0.6$</TEX>), were fabricated by sol-gel method. The effects of sintering and substitution on their crystallographic magnetic properties studied. X-ray diffractometry <TEX>$Mn_{0.6}Ni_{0.4}Fe_2O_4$</TEX> ferrite sintered above 523 K indicated a spinel structure; particles increased in size with hotter sintering. M<TEX>$\ddot{o}$</TEX>ssbauer spectrum this at could be fitted as single quadrupole...

The J-V characteristics of metal-insulator-semiconductor solar cells fabricated on Si samples which are damaged (lapped) with 1-μm grit size Al2O3 substantially degraded. introduction copper at 250–400 °C passivates the dislocations. is diffused in from surface. Anodic oxidation followed by etching aqua regia and 48% HF was used to remove excess remaining surface etch away controlled amounts silicon wafers. experimental results compared model Divigalpitiya Morrison [J. Appl. Phys. 60, 406...

<TEX>$Mn_xFe_{3-x}O_4$</TEX> powders have been fabricated by using sol-gel methods; their crystallographic and magnetic properties were investigated X-ray diffraction, scanning electron microscopy, M<TEX>$\ddot{o}$</TEX>ssbauer spectroscopy, vibrating sample magnetometer. The ferrite annealed at <TEX>$500^{\circ}C$</TEX> had a single spinel structure regardless of the <TEX>$Mn^{2+}$</TEX>-doping amount lattice constants became larger as <TEX>$Mn^{2+}$</TEX> concentration was increased. Their...

졸-겔법을 이용하여 나노 입자 <TEX>$MnFe_2O_4$</TEX>를 제조하여 x-선 회절법(XRD) 및 주사전자현미경(SEM) 측정을 통하여 결정학적 특성 입자의 크기를 연구하였으며, 제조된 나노입자의 초상자성 성질을 <TEX>$M{\ddot{o}}ssbauer$</TEX> 분광법, 진동시료 자화율 측정기(VSM)를 연구하였다. XRD SEM의 측정으로부터 열처리 온도가 <TEX>$250^{\circ}C$</TEX>에서 순수한 큐빅 스피넬 구조를 가지며, 이 때 열처리한 시료의 평균입자 크기는 17 nm 임을 알 수 있었다. 분광실험으로 입자가 상온에서 초상자성의 특성을 가지고 있음을 있었으며, 4.2 K에서의 초미세자기장은 <TEX>$H_{hf}$</TEX>(B-자리) = 508, <TEX>$H_{hf}$</TEX>(A-자리) 475 kOe, 이성질체 이동값은 0.35(B-자리), 0.33 mm/s(A-자리)로 분석되었다. 갖는...

We aimed to find the exposure level of environmental harmful substances related secondhand smoke (SHS) using a nationally representative data general population in Korea.Total 3,533 people were included this study. compared proportion exceeding 95 percentile concentrations by sex according SHS exposure. 16 kinds tobacco analyzed including heavy metals, polycyclic aromatic hydrocarbons, volatile organic compounds, and phenol. For substances, odds ratios (ORs) for each substance calculated...

AlxCoFe2−xO4(0.00 ≤ x 0.20) ferrite powders were fabricated by the sol–gel method. The growth of particles and crystallographic magnetic properties investigated using X-ray diffraction, field emission electro microscopy, Mössbauer spectroscopy, a vibrating sample magnetometer. AlxCoFe2−xO4 (x = powder annealed at 773 K has only single spinel structure behaves ferrimagnetically. Powder 673 coexistence paramagnetic ferrimagnetic phases. Study on behavior show that an increase in annealing...

We aimed to find the relationship between sleep duration and impaired fasting glucose according working type in non-regular workers using 2016 2017 Korean National Health And Nutrition Examination (KNHANE, 7th revision).In 1st 2nd year (2016, 2017) of KNHANE, 16,277 people participated. Minors were excluded because this study was intended for individuals aged 19 years older. As based on wage workers, unemployment, self-employed employers, unpaid family those who have insufficient answers...