96 research outputs found

    Sulfur analysis of Bolu-Mengen lignite before and after microbiological treatment using reductive pyrolysis and gas chromatography/mass spectrometry

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    Atmospheric pressure-temperature programmed reduction coupled with on-line mass spectrometry (AP-TPR/MS) is used for the first time on microbiologically treated coal samples as a technique to monitor the degree of desulfurization of the various sulfur functionalities. The experimental procedure enables the identification of both organic and inorganic sulfur species present in the coal matrix. A better insight in the degradation of the coal matrix and the accompanying processes during the AP-TPR experiment is obtained by a quantitative differentiation of the sulfur. The determination of the sulfur balance for the reductive pyrolysis gives an overview of the side reactions and their relative contribution in the total process. The volatile sulfur species are unambiguously identified using AP-TPR off-line coupled with gas chromatography/mass spectrometry (GC/MS). In this way, fundamental mechanisms and reactions that occur during the reductive pyrolysis could be quantified, explaining the differences in AP-TPR recoveries. Therefore, this study gives a clearer view on the possibilities and limitations of AP-TPR as a technique to monitor sulfur functionalities in coal

    The influence of alloying or interdiffusion on the superconducting properties of ferromagnet/superconductor layered systems

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    We present the theoretical investigation of alloying or interdiffusion at the interface on the superconducting properties of ferromagnet/superconductor (S/F) layered films. The intermixed layer is modeled by the nonsuperconducting alloy (A) layer, which is characterized by strong scattering on paramagnetic impurities. The linearized Usadel equations are derived, which take into account the exchange scattering of excitations on the paramagnetic impurities in the alloyed layer. The superconducting transition temperature of the S/A/F trilayer is calculated as a function of spin-dependent scattering strength and thickness of A-layer. The nonmonotonic behavior of superconducting T c at the onset of ferromagnetism in F-layer is discussed in the framework of the presented theory. The oscillations of T c due to ferromagnetic layer thickness variation, and additional influence introduced by an alloy layer, are investigated. © 2001 Elsevier Science B.V. All rights reserved

    FMR and magnetization study of NiFe/Ag/CoNi trilayer film

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    The polycrystalline FeNi/Ag/CoNi asymmetric trilayer films were prepared by the UHV magnetron sputtering on silicon. In plane magnetization measurements showed double-step hysteresis loops. Magnetoresistancc (MR) measurements revealed giant magnetoresistance effect with magnitudes in 0. 15-0. 29% range at room temperature. The saturation magnetizations and the interaction between layers were studied by ferromagnetic resonance and revealed an undistinguishably weak interlayer coupling from out-of-plane geometry of measurements. The MR data are interpreted based on the incomplete domain alignment model for polycrystalline magnetic films. © 1998 IEEE

    Completeness of hepatitis, brucellosis, syphilis, measles and HIV/AIDS surveillance in Izmir, Turkey

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    <p>Abstract</p> <p>Background</p> <p>According to the surveillance system in Turkey, most diseases are notified only by clinicians, without involving laboratory notification. It is assumed that a considerable inadequacy in notifications exists; however, this has not been quantified by any researcher. Our aim was to evaluate the completeness of communicable disease surveillance in the province of Izmir, Turkey for the year of 2003 by means of estimating the incidences of diseases.</p> <p>Methods</p> <p>Data on positive laboratory results for the notifiable and serologically detectable diseases hepatitis A, B, C, brucellosis, syphilis, measles and HIV detected in 2003 in Izmir (population 3.5 million) were collected from serology laboratories according to WHO surveillance standards and compared to the notifications received by the Provincial Health Directorate. Data were checked for duplicates and matched. Incidences were estimated with the capture-recapture method. Sensitivities of both notifications and laboratory data were calculated according to these estimates.</p> <p>Results</p> <p>Among laboratories performing serologic tests (n = 158) in Izmir, 84.2% accepted to participate, from which 23,515 positive results were collected. Following the elimination of duplicate results as well as of cases residing outside of Izmir, the total number was 11,402. The total number of notifications was 1802. Notification rates of cases found in laboratories were 31.6% for hepatitis A, 12.1% for acute hepatitis B, 31.8% for brucellosis, 25.9% for syphilis and 100% for HIV confirmation.</p> <p>Conclusions</p> <p>It was discovered that for hepatitis A, B, C, brucellosis and syphilis, there is a considerable under-notification by clinicians and that laboratory data has the potential of contributing greatly to their surveillance. The inclusion of laboratories in the surveillance system of these diseases could help to achieve completeness of reporting.</p

    Meson-Meson Scattering in the Quark Model: Spin Dependence and Exotic Channels

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    We apply a quark interchange model to spin-dependent and exotic meson-meson scattering. The model includes the complete set of standard quark model forces, including OGE spin-orbit and tensor and scalar confinement spin-orbit. Scattering amplitudes derived assuming SHO and Coulomb plus linear plus hyperfine meson wavefunctions are compared. In I=2 pi pi we find approximate agreement with the S-wave phase shift from threshold to 1.5 GeV, where we predict an extremum that is supported by the data. Near threshold we find rapid energy dependence that may reconcile theoretical estimates of small scattering lengths with experimental indications of larger ones based on extrapolation of measurements at moderate kpi^2. In PsV scattering we find that the quark-quark L*S and T forces map into L*S and T meson-meson interactions, and the P-wave L*S force is large. Finally we consider scattering in J^PC-exotic channels, and note that some of the Deck effect mechanisms suggested as possible nonresonant origins of the pi_1(1400) signal are not viable in this model.Comment: 51 pages, 10 figures, uses epsf.sty epsfig.st

    Occupational exposure to dusts and risk of renal cell carcinoma

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    Background: Occupational exposures to dusts have generally been examined in relation to cancers of the respiratory system and have rarely been examined in relation to other cancers, such as renal cell carcinoma (RCC). Although previous epidemiological studies, though few, have shown certain dusts, such as asbestos, to increase renal cancer risk, the potential for other occupational dust exposures to cause kidney damage and/or cancer may exist. We investigated whether asbestos, as well as 20 other occupational dust exposures, were associated with RCC risk in a large European, multi-center, hospital-based renal case-control study.Methods: General occupational histories and job-specific questionnaires were reviewed by occupational hygienists for subject-specific information. Odds ratios (ORs) and 95% confidence intervals (95% CIs) between RCC risk and exposures were calculated using unconditional logistic regression. Results: Among participants ever exposed to dusts, significant associations were observed for glass fibres (OR: 2.1; 95% CI: 1.1-3.9), mineral wool fibres (OR: 2.5; 95% CI: 1.2-5.1), and brick dust (OR: 1.5; 95% CI: 1.0-2.4). Significant trends were also observed with exposure duration and cumulative exposure. No association between RCC risk and asbestos exposure was observed. Conclusion: Results suggest that increased RCC risk may be associated with occupational exposure to specific types of dusts. Additional studies are needed to replicate and extend findings. © 2011 Cancer Research UK All rights reserved

    Dezavantajlı bir grupta işyerinde sigarayı bırakma programının bir yıllık sonuçları

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    Aim: Our aim was to introduce and evaluate a smoking cessation program conducted among Izmir Bayraklı Municipality's cleaning workers in 2010. Materials and Methods: The intervention started in March 24,2010. The first 27 participants attended a session and then individual counseling was conducted face-to-face at the workplace. The following 28 participants were only given individual counseling. Knowledge was assessed by a 20-item questionnaire applied before and one month after education. Participants were contacted by telephone to evaluate the six-month and one-year results. Results: The mean age of the 55 participants was 33.4;plusmn;6.9 (23-54) years and only three were women. Sixty percent had primary school or lower education. The mean age at starting smoking was 15.3;plusmn;3.3 years and the mean daily consumption 21.6;plusmn;11.7 cigarettes. Most of the participants had smoked ;gt;10 pack-years (72.7%). There was a significant increase in the knowledge level of the participants, particularly on issues concerning quitting, but not of the harmful effects of smoking. Although pharmacologic treatment was proposed to 46 of the participants, only 18 used the treatment, due to mainly economic reasons (n=18). Participants were followed up 6.2;plusmn;3.5 times (1-15) on the average, including the first counseling. At six months, 13/48 (27.1%) and at one-year, 11/43 (26.2%) participants had quit smoking. Among the followed-up participants at one year, 16 (38.1%) had decreased consumption by a mean of 12.9;plusmn;8.9 (3-30) cigarettes per day. Conclusion: The application of smoking cessation programs at workplaces could have a significant impact in lowering adult smoking rates. The reduction of the costs of cessation treatment or their coverage by the security scheme will improve the outcome.Amaç: İşyerinde sigara bıraktırma girişimlerinin birçok avantajı bulunmaktadır. Bu çalışmanın amacı, İzmir Bayraklı Belediyesi'nin temizlik işleri çalışanlarında 2010 yılında yürütülen sigarayı bırakma programını tanıtmak ve programın etkinliğini değerlendirmektir. Gereç ve Yöntem: Program 24 Mart 2010 tarihinde başlamıştır. İlk üç hafta içinde katılan 27 kişiye eğitim seansının ardından bireysel danışmanlık, sonraki haftalarda katılan 28 kişiye ise bireysel danışmanlık kapsamında eğitim verilmiştir. Eğitim öncesi ve en az bir ay sonrasında 20 maddelik bir soru formuyla bilgi düzeyi sorgulanmıştır. Eğitimler ve izlemler işyerinde yüz yüze gerçekleştirilmiştir. Girişimin altı aylık ve bir yıllık sonuçlarının değerlen-dirilmesi için katılımcılar telefonla aranmıştır. Bulgular: 55 kişiden oluşan araştırma grubunun yaş ortalaması 33,4±6,9'dur (23-54) ve sadece üçü kadındır. Grubun %60'ının eğitim düzeyi ilkokul ve altındadır. Grubun sigaraya başlama yaş ortalaması 15,3±3,3, günde içtikleri sigara sayısı ortalama 21,6±11,7'dır. Katılımcıların çoğunun 10 paket yılının üzerinde tüketimi vardır (%72,7). Katılımcıların bilgi düzeylerinde anlamlı artış saptanmıştır. Bilgi artışı sigaranın sağlığa etkilerinden ziyade bırakma tedavileriyle ilgili konularda olmuştur. Katılımcıların 46'sına farmakolojik tedavi önerildiği halde sadece 18'i önerilen tedaviyi uygulayabilmiştir. Önde gelen uygulayamama nedeni ekonomik sıkıntıdır (n=18). Katılımcılar ilk görüşmeyle birlikte ortalama 6,2±3,5 (1-15) kez izlenmişlerdir. Altı ayın sonunda izlemi tamamlanan 48 kişiden 13'ü (%27,1), bir yılın sonunda 43 kişiden 11'i (%26,2) sigarayı bırakmıştı. Bir yıllık izlemi yapılabilenlerin 16'sı da (%38,1) günlük içtiği sigara sayısını ortalama 12,9±8,9 (3-30) adet azaltmıştır. Sonuç: İşyerlerinde sigara bırakma programlarının uygulanması, bunun işyeri hekimliği eğitiminin bir parçası olması erişkin sigara bırakma oranlarının düşürülmesine önemli katkılar koyabilir. Sigara bırakma tedavilerinin maliyetlerinin düşürülmesi veya bunların güvence kapsamına alınması başarıyı arttıracaktır
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