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101.
The effects of vowels on voice perturbation measures 总被引:1,自引:0,他引:1
Mehmet Akif Kili? Fatih O?üt Gürsel Dursun Erdo?an Okur Ilhami Yildirim Ra?it Midilli 《Journal of voice》2004,18(3):318-324
This study examines voice perturbation parameters of the sustained [a] in English and of the eight vowels in Turkish to discover whether any difference exists between these languages, and whether a correlation exists between voice perturbation parameters and articulatory and acoustic properties of the Turkish vowels. Eight Turkish vowels uttered by 26 healthy nonsmoker volunteer males who are native Turkish speakers were compared with a voice database that includes samples of normal and disordered voices belonging to American English speakers. Fundamental frequencies, the first and second formants, and perturbation parameters, such as jitter percent, pitch perturbation quotient, shimmer percent, and amplitude perturbation quotient of the sustained vowels, were measured. Also, the first and second formants of the sustained [a] in English were measured, and other parameters have been obtained from the database. When the voice perturbation parameters in Turkish and English were compared, statistically significant differences were not found. However, when Turkish vowels compared with each other, statistically significant differences were found among perturbation values. Categorical comparisons of the Turkish vowels like high-low, rounded-unrounded, and front-back revealed significant differences in perturbation values. In correlation analysis, a weak linear inverse relation between jitter percent and the first formant (r=-0.260, p<0.05) was found. 相似文献
102.
Kemal Sancak Mustafa Er Yasemin Ünver Melike Yildirim Ismail Degirmencioglu Kerim Serbest 《Transition Metal Chemistry》2007,32(1):16-22
The synthesis and structural properties of two novel compounds, 4-amino-5-(thien-2-yl ethyl)-2,4-dihydro-3H-1,2,4-triazol-3-one
and 4-{[(2-hydroxy-1-naphthyl)methyl-ene]amino}-5-(thien-2-ylmethyl) − 2,4-dihydro-3H-1,2,4-triazol-3-one have been described.
4-Amino-5-(thien-2-ylmethyl)-2,4-dihydro-3H-1,2,4-triazol-3-one was synthesized by treating N-propionyl-2-thien-2-ylethane-hydrazonoate with hydrazine hydrate and the Schiff base was obtained from condensation of substituted
amine with 2-hydroxy-1-naphthaldehyde. The Cu(II), Ni(II) and Fe(II) complexes were prepared and characterized by elemental
analyses, IR, magnetic moment, UV–Vis, mass spectral data and 1H- and 13C-NMR IR spectra. The Schiff base is coordinated to the metal ions in a tridentate manner with OON donors of the phenolic
O, carbonyl O and triazolic N. From the magnetic and UV spectral data, it was found the geometrical structure of Cu(II) and
Fe(II) ions are octahedral while Ni(II) ion is square planar.Ab-inito 6-31 G* level calculations provided structural information and IR data that were in good agreement with experimental results. 相似文献
103.
A series of ester formylhydrazones 2 were synthesized from the reaction of alkyl imidate hydrochlorides 1 with formylhydrazine. Treatment of 2 with hydrazine hydrate, ethyl carbazate and tert-butyl carbazate led to the formation of 3-alkyl-4-amino-, 3-alkyl-4-ethoxycarbonylamino- and 3-alkyl-4-tert-butoxycar-bonylamino-4H-1,2,4-triazoles 3–5 , respectively. Reaction of compounds 2 with formylhydrazine gave N,N'-diformylhydrazine 6 . Compounds 2 were reacted with 2,5-dimethoxytetrahydrofuran to afford 3-alkyl-4-(1H-pyrrol-1-yl)-4H-1,2,4-triazoles 8 . 相似文献
104.
Ozturk Tugba Cengiz Elif Ceylan Demir-Cakan Rezan Erbil H. Yildirim 《Journal of Solid State Electrochemistry》2022,26(8):1747-1759
Journal of Solid State Electrochemistry - Porous cathodes are preferred to be used in lithium-sulfur (Li–S) batteries for better impregnation of the active material. On the other hand, the... 相似文献
105.
Margaux Fresnais Esra Yildirim Seda Karabulut Dirk Jger Inka Zrnig Julia Benzel Kristian W. Pajtler Stefan M. Pfister Jürgen Burhenne Walter E. Haefeli Rmi Longuespe 《Molecules (Basel, Switzerland)》2021,26(5)
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has rarely been used in the field of therapeutic drug monitoring, partly because of the complexity of the ionization processes between the compounds to be quantified and the many MALDI matrices available. The development of a viable MALDI-MS method that meets regulatory guidelines for bioanalytical method validation requires prior knowledge of the suitability of (i) the MALDI matrix with the analyte class and properties for ionization, (ii) the crystallization properties of the MALDI matrix with automation features, and (iii) the MS instrumentation used to achieve sensitive and specific measurements in order to determine low pharmacological drug concentrations in biological matrices. In the present hybrid article/white paper, we review the developments required for the establishment of MALDI-MS assays for the quantification of drugs in tissues and plasma, illustrated with concrete results for the different steps. We summarize the necessary parameters that need to be controlled for the successful development of fully validated MALDI-MS methods according to regulatory authorities, as well as currently unsolved problems and promising ways to address them. Finally, we propose an expert opinion on future perspectives and needs in order to establish MALDI-MS as a universal method for therapeutic drug monitoring. 相似文献
106.
In this work, the backaction of a detector on light reflected from a dielectric medium is theoretically studied in the far-field region by considering every order of light scattering both within the medium and between the detector and the medium. It is found that, as a result of the backaction, the light actually measured by the detector is different from that when the detector is absent, and that the strength of the backaction depends on several factors, such as the separation between the detector and the medium, the medium’s density, and the light wavelength. Also presented is a method that allows the reflected light in the absence of the detector to be derived from the reflected light measured by the detector. 相似文献
107.
Herzer N Guneysu H Davies DJ Yildirim D Vaccaro AR Broer DJ Bastiaansen CW Schenning AP 《Journal of the American Chemical Society》2012,134(18):7608-7611
A printable H-bonded cholesteric liquid crystal (CLC) polymer film has been fabricated that, after conversion to a hygroscopic polymer salt film, responds to temperature and humidity by changing its reflection color. Fast-responding humidity sensors have been made in which the reflection color changes between green and yellow depending on the relative humidity. The change in reflection band is a result of a change in helix pitch in the film due to absorption and desorption of water, resulting in swelling/deswelling of the film material. When the polymer salt was saturated with water, a red-reflecting film was obtained that can potentially act as a time/temperature integrator. Finally, the films were printed on a foil, showing the potential application of supramolecular CLC materials as low-cost, printable, battery-free optical sensors. 相似文献
108.
This paper proposes an affine-based approach which jointly captures the nominal interest rate, the real interest rate, and the inflation risk premium to price inflation-indexed derivatives, including zero-coupon inflation-indexed swaps, year-on-year inflation-indexed swaps, inflation-indexed swaptions, and inflation-indexed caps and floors. We provide an example and explain how to use traded zero-coupon inflation-indexed swap rates to estimate inflation risk premiums. 相似文献
109.
Ilhami Celik 《Tetrahedron》2009,65(25):4923-4929
N-Protected dipeptidoylbenzotriazoles react with aqueous ammonia to give dipeptide primary amides (77-98%) and with N-unprotected α-amino amides to afford tripeptide primary amides (82-86%). 相似文献
110.
Yener G Üner M Gönüllü Ü Yildirim S Kiliç P Aslan SS Barla A 《Chemical & pharmaceutical bulletin》2010,58(11):1466-1473
Transdermal patches of meloxicam (MX) and lornoxicam (LX) were aimed to be prepared in order to overcome their side effects by oral application. The strategy was formulation of optimized films to prepare transdermal patches by determination of physical properties and investigation of drug-excipient compatibility. As the next step, in vitro drug release, assesment of anti-inflammatory effect on Wistar Albino rats, ex vivo skin penetration and investigation of factors on drug release from transdermal patches were studied. Hydroxypropyl methylcellulose (HPMC) was concluded to be suitable polymer for formulation of MX and LX transdermal films indicating pharmaceutical quality required. MX and LX transdermal patches gave satisfactory results regarding to the edema inhibition in the assessment of anti-inflammatory effect. MX was found out to be more effective compared to LX on relieving of edema and swelling. These results were supported by data obtained from ex vivo penetration experiments of drug through rat skin. Indicative parameters like log P, molecular weight and solubility constraint on penetration rate of drugs also indicated good skin penetration. Transdermal patches of MX and LX can be suggested to be used especially for the immediate treatment of inflammated area since it displays anti-inflammatory effect, soon. 相似文献