Qs Values Research Articles

Investigation of the Temporal Change in Attenuation Within the Ruptured Fault Zone of the 1999 Mw7.3 Chi-Chi, Taiwan Earthquake

A decrease in Q s values within the hanging wall of the ruptured Chelungpu fault two years following the 1999 Chi-Chi earthquake was revealed by Q s tomography images and an analysis of single-path Q s. The synthetic and sensitivity tests of the Q s determination were carried out accordingly to justify the temporal variation. A Q s value within the hanging wall above the hypocenter was determined to be 157 ± 18 two years following the Chi-Chi earthquake, which is significantly lower than the Q s tomography values of 238 ± 17 and 289 ± 13 prior to and two years after the main shock, respectively. Similar values using a signal-path Q s analysis from events within the ruptured fault zone to stations along the fault were obtained. The corresponding Q s values were 247 ± 85 prior to the Chi-Chi earthquake. After the earthquake we obtained Q s values of 158 ± 75 and 318 ± 80 for 2 years following and 2 years after the earthquake, respectively. Considering the two independent methods in determination of Q s, the reduction in Q s by 89 two years following the Chi-Chi earthquake in both methods is significant. Along with 1 % V s reduction revealed by the analysis of repeating earthquakes our studies suggested possible reduction both in V s and Q s values within the fault zone after the Chi-Chi earthquake. Temporal changes in Q s after the Chi-Chi earthquake imply variations of pore-fluid saturation in the ruptured fault zone. The reduction in Q s two years following the Chi-Chi earthquake indicates high pore-fluid saturation within the fractured fault zone due to the postseismic fluid redistribution.

Thermal conditions of the central Sinai Microplate inferred from new surface heat-flow values and continuous borehole temperature logging in central and southern Israel

This paper reports ten new surface heat-flow density (qs) values for central and southern Israel (central Sinai Microplate), whose crystalline crust and lithosphere formed as part of the Neoproterozoic Arabian-Nubian Shield. Heat flow was calculated in Mesozoic sediments using the classical approach of heat-flow determination by implementing in the analysis high-precision continuous temperature logs obtained in air- and/or water-filled boreholes. Thermal conductivity (TC) measured for a large suite of rock samples of lithotypes making up the sequence was assigned to temperature gradients in intervals for which the lithology was known. The heat-flow values obtained for different depth intervals in a borehole as well as the average values for the individual borehole locations cover a narrow range, attesting heat-conduction conditions. A steady-state thermal model along an E–W crustal cross section through the area shows that the observed systematic spatial distribution of the qs values, which range between 50 and 62mWm−2, can primarily be explained by variations in the thickness of the upper crust and in the ratio between sedimentary and crystalline rocks therein. Given the time lapse of thermal heat transfer through the lithosphere, the qs data monitor the crustal thermal conditions prior to rift- and plume-related lithospheric thermal perturbations that have started in the larger area ca. 30Ma ago. Observed and modeled qs display the best fit for a pre-Oligocene lithosphere–asthenosphere boundary (LAB) at ∼150km, which would be at the upper end of LAB depths determined from stable areas of the Arabian Shield (150–120km) not affected by the young, deep-seated thermal processes that have caused a further uprise of the LAB. Our data imply or predict that the surface heat flow of the Sinai Microplate generally tends to increase along N–S and W–E traverses, from ∼45–50mWm−2 to ∼55–60mWm−2. Surface heat flows on the order of 55–60mWm−2 may be common in the northern Arabian Shield, where it exhibits typical lithosphere structure and composition and is unaffected by young heating processes, compared to values of ≤45mWm−2 recently determined in the southern Arabian Plate for the Arabian Platform.

Attenuation of High-Frequency Seismic Waves in Eastern Iran

We investigated the frequency-dependent attenuation of the crust in Eastern Iran by analysis data from 132 local earthquakes having focal depths in the range of 5–25 km. We estimated the quality factor of coda waves (Qc) and body waves (Qp and Qs) in the frequency band of 1.5–24 Hz by applying the single backscattering theory of S-coda envelopes and the extended coda-normalization method, respectively. Considering records from recent earthquakes (Rigan Mw 6.5, 2010/12/20, Goharan Mw 6.2, 2013/5/11 and Sirch Mw 5.5, 2013/1/21), the estimated values of Qc, Qp and Qs vary from 151 ± 49, 63 ± 6, and 93 ± 14 at 1.5 Hz to 1,994 ± 124, 945 ± 84 and 1,520 ± 123 at 24 Hz, respectively. The average frequency-dependent relationships (Q = Qofn) estimated for the region are Qc = (108 ± 10)f(0.96±0.01), Qp = (50 ± 5)f(1.01±0.04), and Qs = (75 ± 6)f(1.03±0.06). These results evidenced a frequency dependence of the quality factors Qc, Qp, and Qs, as commonly observed in tectonically active zones characterized by a high degree of heterogeneity, and the low value of Q indicated an attenuative crust beneath the entire region.

Influence of phenolic substrates utilised by yeast Trichosporon cutaneum on the degradation kinetics

The degradation kinetics of different phenolic substrates utilised by Trichosporon cutaneum R57 was studied. The following compounds were used as substrates: phenol, resorcinol, hydroquinone, 3-nitrophenol, 2,6-dinitrophenol, 3-chloro phenol and p-cresol. The specific degradation rates (Qs) were described by a Haldane kinetic model. The unknown model parameters were estimated using the mathematical optimisation procedure for direct search. The results obtained demonstrated that Qs varied greatly in the experiments carried out. The level of biodegradability depended on the different structure and toxicity of compounds used as carbon substrates. The highest Qs values were observed for less toxic hydroxylated phenols (0.77–0.85 h−1), while the most toxic chlorinated phenols were characterised with the lowest Qs values (0.224 h−1). The results obtained with different concentrations of resorcinol (from 0.2 to 0.8 g L−1) and 2,6-dinitrophenol (from 0.2 to 0.7 g L−1) demonstrated a growing inhibitory effect directly correlating with the extended time necessary for complete degradation of both compounds.

Pressure-driven deformation with soft polydimethylsiloxane (PDMS) by a regular syringe pump: challenge to the classical fluid dynamics by comparison of experimental and theoretical results

Pressure-driven flows through optically transparent polydimethylsiloxane (PDMS) microfluidic channels using a syringe pump are common in many experimental applications. However, because of small changes, the pressure-induced deformations due to soft materials and shapes and patterns in the microchannels, which generate untargeted flow velocity and pressure drop, have been easily ignored. In this paper, we present a simple experimental investigation with circular-shaped, periodically arranged objects of three different characteristic dimensions, as well as various channel heights ranging from 15 μm to 200 μm. The resultant CCD images and pressure data were used to determine the extent of the start-up transients and evaluate the establishment of quasi-steady flow conditions. Channel deformation, measured by fluorescence intensity difference, was severe in shallow microchannels that had characteristically large obstacles. In addition, PDMS microchannel bulging effects in shallow microchannels exerted a greater deleterious effect on (ΔP/Δx)QS values than upon VQS for the experiments using a volumetrically controlled syringe pump. The discrepancy between experimental and theoretical (ΔP/Δx) increased with decreasing microchannel height. This means that the severe PDMS bulging observed in shallow microchannels using a syringe pump can generate large deviations from the desired experimental result. As a result, the slope of Darcy friction factors plotted against the Reynolds number indicates that the slope was strongly dependent on microfluidic channel height and the degree of PDMS bulging. The microfluidic channel with the greatest height exhibited the smallest bulging effect and was shown to be in relatively good agreement with predicted values, while the slope became much steeper than −1 as channel heights decreased.

Physical state of Himalayan crust and uppermost mantle: Constraints from seismic attenuation and velocity tomography

AbstractWe jointly interpret P and S wave seismic attenuation (1/Q) along with previously published seismic velocity results for the crust and uppermost mantle of eastern Nepal and the southern Tibetan Plateau. Seismic attenuation measurements can provide information complementary to seismic velocity estimates and can help distinguish between compositional and thermal mechanisms for observed anomalies. In addition to a dramatic change in seismic velocity observed between the crust of Nepal and southern Tibet, we find a large increase in seismic attenuation from high Q (low attenuation) in eastern Nepal to low Q (high attenuation) in the crust beneath southern Tibet for both P waves and S waves. We interpret the broad zone of low Q values in the southern Tibetan crust as thermal in origin, requiring an elevated geotherm (warm) relative to Nepal, with low VP/VS corresponding to a dominantly felsic middle and upper crust beneath southern Tibet. We find a sharply bounded region with enhanced low Q and high VP/VS at 45–50 km depth beneath southern Tibet, which we suggest may be due to trapped fluid beneath an impermeable cap associated with the crustal alpha‐beta quartz transition. Using calibrations from mineral physics, the alpha‐beta quartz transition suggests a temperature of 930–960°C at 45 km depth (50 km beneath the surface) beneath the southern Tibetan Plateau. High values of QP and QS throughout the uppermost mantle in the region are consistent with cool temperatures in the underthrusting Indian Plate, contributing to brittle conditions and earthquakes in the uppermost mantle.

Estimation of Source Parameters, Quality Factor (QS), and Site Characteristics Using Accelerograms: Uttarakhand Himalaya Region

Research Article| December 24, 2013 Estimation of Source Parameters, Quality Factor (QS), and Site Characteristics Using Accelerograms: Uttarakhand Himalaya Region Jyoti Sharma; Jyoti Sharma aInstitute of Seismological Research (ISR), Department of Science and Technology, Government of Gujarat, Village—Raisan, Gandhinagar, Gujarat 382009, Indiajyotisharmaiitkgp@gmail.com Search for other works by this author on: GSW Google Scholar Sumer Chopra; Sumer Chopra bMinistry of Earth Sciences (MoES), Government of India, Prithvi Bhavan, Seismology Division, Lodhi Road, New Delhi 110003, India Search for other works by this author on: GSW Google Scholar Ketan Singha Roy Ketan Singha Roy aInstitute of Seismological Research (ISR), Department of Science and Technology, Government of Gujarat, Village—Raisan, Gandhinagar, Gujarat 382009, Indiajyotisharmaiitkgp@gmail.com Search for other works by this author on: GSW Google Scholar Author and Article Information Jyoti Sharma aInstitute of Seismological Research (ISR), Department of Science and Technology, Government of Gujarat, Village—Raisan, Gandhinagar, Gujarat 382009, Indiajyotisharmaiitkgp@gmail.com Sumer Chopra bMinistry of Earth Sciences (MoES), Government of India, Prithvi Bhavan, Seismology Division, Lodhi Road, New Delhi 110003, India Ketan Singha Roy aInstitute of Seismological Research (ISR), Department of Science and Technology, Government of Gujarat, Village—Raisan, Gandhinagar, Gujarat 382009, Indiajyotisharmaiitkgp@gmail.com Publisher: Seismological Society of America First Online: 14 Jul 2017 Online ISSN: 1943-3573 Print ISSN: 0037-1106 Bulletin of the Seismological Society of America (2014) 104 (1): 360–380. https://doi.org/10.1785/0120120304 Article history First Online: 14 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jyoti Sharma, Sumer Chopra, Ketan Singha Roy; Estimation of Source Parameters, Quality Factor (QS), and Site Characteristics Using Accelerograms: Uttarakhand Himalaya Region. Bulletin of the Seismological Society of America 2013;; 104 (1): 360–380. doi: https://doi.org/10.1785/0120120304 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract A study of source, path, and site characteristics was conducted for the Uttarakhand Himalaya region using accelerogram data from 15 earthquakes (ML≥3.5). These earthquakes were recorded at the 16‐station accelerograph network operated by the Indian Institute of Technology, Roorkee, during 2005–2011. The average seismic moment (M0) of the studied earthquakes ranges between 1.20×1022 and 1.02×1024 dyn·cm, and the average moment magnitude (Mw) is between 4.0 and 5.3. The estimated corner frequency (fc) varies from 1.1 to 3.3 Hz, radius of rupture (rd) from 0.5 to 1.4 km, and stress drop (Δσ) from 6 to 172 bars, indicating continuous seismic energy release in the Uttarakhand region. The interdependence between estimated source parameters is shown by determining scaling laws for the studied region. The constant Q0 of the shear‐wave quality factor (QS=Q0fn) varies between 40 and 300 and exponent n varies between 0.85 and 1.5, providing an average relation of QS=174f1.27. However, least‐square fitting of the observed data set in the frequency range 0.1–20 Hz gives QS as 159f1.16. The value of QS demonstrates that the region is heterogeneous, seismically active, and attenuative. The high‐frequency spectral fall‐off factor (γ) varies from 1.3 to 2.1 and the upper crustal attenuation factor (κ) from 0.023 to 0.07 s at different sites, with an average of 0.044 s. The site response characteristics are estimated by horizontal‐to‐vertical spectral ratio (HVSR) and generalized inversion (GINV) techniques; results obtained from both the techniques show 1:1 correspondence. The site amplification factor varies between 2.3 and 9.4 using HVSR and between 2.6 and 10.9 using GINV among different stations. The predominant frequency ranges from 1.3 to 8.3 Hz with HVSR and from 1.3 to and 9.0 Hz with GINV.Online Material: Tables of source, path, and site parameters with associated errors at different sites for the earthquakes recorded from December 2005 to March 2011. Figures represent accelerogram records, source spectra matching, and site amplification patterns. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Estimation of Q p and Q s of Kinnaur Himalaya

The attenuation characteristics of the Kinnaur area of the North West Himalayas were studied using local earthquakes that occurred during 2008–2009. Most of the analyzed events are from the vicinity of the Panjal Thrust (PT) and South Tibetan Detachment Thrust, which are well-defined tectonic discontinuities in the Himalayas. The frequency-dependent attenuation of P and S waves was estimated using the extended coda normalization method. Data from 64 local earthquakes recorded at 10 broadband stations were used. The coda normalization of the spectral amplitudes of P and S waves was done at central frequencies of 1.5, 3, 6, 9, and 12 Hz. Qp increases from about 58 at 1.5 Hz to 706 at 12 Hz, and Qs increases from 105 at 1.5 Hz to 1,207 at 12 Hz. The results show that the quality factors for both P and S waves (Qp and Qs) increase as a function of frequency according to the relation Q = Qofn, where Qo is the corresponding Q value at 1 Hz frequency and “n” is the frequency relation parameter. We obtained Qp = (47 ± 2)f(1.04±0.04) and Qs = (86 ± 4)f(0.96±0.03) by fitting power law dependency model for the estimated values of the entire study region. The Q0 and n values show that the region is seismically very active and the crust is highly heterogeneous. There was no systematic variation of values of Qp and Qs at different frequencies from one tectonic unit to another. As a consequence, average values of these parameters were obtained for each frequency for the entire region, and these were used for interpretation and for comparison with worldwide data. Qp values lie within the range of values observed for some tectonically active regions of the world, whereas Qs values were the lowest among the values compared for different parts of the world. Qs/Qp values were >1 for the entire range of frequencies studied. All these factors indicate that the crust is highly heterogeneous in the study region. The high Qs/Qp values also indicate that the region is partially saturated with fluids.

Charged Hadron Multiplicity at RHIC and LHC Energies from Color Glass Condensate

We investigate charged hadron production at RHIC and LHC energies in the framework of color glass condensate. Our study gives a very good description of the experimental data of inclusive charged hadron production in proton—proton collisions at both RHIC and LHC energies. The saturation scale is treated as a free parameter, which will reduce the uncertainties from fitting low-energy experimental data and the modeling of the saturation momentum. We find a reasonable value of the saturation scale Qs ∼ 1 GeV, which is consistent with the theoretical findings. The running coupling effect is taken into account, and it is found that it plays an important role in the description of the experimental data. We provide quantitative predictions of the rapidity dependence of the inclusive charged hadron production for the upcoming LHC experiment in proton—proton collisions at √s = 14TeV.

Shear wave attenuation characteristics over the Central India Tectonic Zone and its surroundings

The study area lies between latitude 18–26°N and longitude 73–83°E, and mainly covers the Central India Tectonic Zone (CITZ). The frequency-dependent shear wave quality factor (Qs) has been estimated over the CITZ and its surroundings using Double Spectral Ratio (DSR) method. We have considered 25 local earthquakes with magnitude (ML) varies from 3.0 to 4.7 recorded at 11 stations running under national seismic network. The Fast Fourier Transformed (FFT) spectra were computed from the recorded waveform having time-window from onset of S-phase to 1.0s and for a frequency-band of 0.1–10Hz. Three different shear wave velocities (i.e., 3.87, 3.39 and 3.96km/s) were obtained over the study area based on a pair of earthquakes recorded at a pair of stations. The low Qs values of 51–96 at 1Hz (i.e., Qs=51f0.49; Qs=90f0.488 and Qs=96f0.53) were found in the area covering the Son–Narmada–Tapti (SONATA) lineament, CITZ, eastern part of the Satpura fold belt, Vindhyan and Gondwana basins, Godavari and Mahanadi grabens, and southern part of Gangetic plain. Intermediate Qs values of the order of 204–277 (i.e., Qs=204f0.56 and Qs=277f0.55) were noted in the cartonic areas, namely, Bundelkhand, Dharwar-Bhandara and Bastar. While the higher Qs values of 391–628 at 1Hz (i.e., Qs=391f0.49,Qs=409f0.48, Qs=417f0.48, Qs=500f0.66, Qs=585f0.65 and Qs=628f0.69) were found in the eastern part of the SONATA, CITZ, and the northeastern part of the Satpura fold belt. The low Qs values might be attributing to the more heterogeneous SONATA rift system. Low Qs values further may presumably be associated with lower-level of seismicity and apparently account for higher tectonic stress accumulation over long duration. The long-term accumulated stress is generally released through occasional triggering of moderate magnitude earthquakes in the SONATA zone. Surrounding the SONATA region, the higher Qs values possibly accounts for a more homogeneous subsurface structure along the SONATA zone.

S-waves and the near surface: A time-lapse study of S-wave velocity and attenuation in the weathering layer of an Alberta heavy oil field

This study used data from a three-month continuous reservoir monitoring experiment in Peace River, Alberta, Canada to measure spatial and temporal variations in near-surface S-wave velocity (VS) and attenuation (QS) in the weathering layer. The permanently buried sources generate a strong refracted S-wave that was recorded on buried 3C receivers. A method to perform receiver-side up-down separation and extract primary and ghost S-wavefields is presented. These wavefields are then used to measure near-surface VS and QS for the near-surface layer above the buried receivers, which is the top 12 m in this case. The measured VS values range between 180 and 220 m/s and QS values between 8 and 22. Maps of VS and QS show a robust correlation (low VS with low QS) and a clear spatial variation that can be associated with soil type. Both properties increase slowly over a three-month period in one section of the survey area while remaining constant in another. The cumulative increase in VS and QS is 10%.

Whole-tree water use by Pinus cembra at the treeline in the Central Tyrolean Alps

Background and Aims: In contrast to the wealth of information on sap flow characteristics of forest trees at low-elevation sites, knowledge is scarce for trees within the treeline ecotone. Thus, our aim was to identify environmental controls on water loss in P. cembra trees at the treeline. Methods: Three isolated individuals were equipped with thermal dissipation probes for monitoring sap flow density (QS ). A Jarvis-type model and multiple linear regression, with irradiance and vapour pressure deficit as explanatory variables, were applied to compare predicted and measured sap flow density. Results: Both models successfully predicted measured QS . The Jarvis model tended to underestimate QS values by 25% on average, as compared with an underestimate of 8% by multiple linear regression analysis. The multiple linear regression analysis also allowed discrimination between effects of irradiance (RS ) and vapour pressure deficit (D) on QS , indicating that RS (ß-coefficient = 0.70) had a greater effect on QS than D (ß-coefficient = 0.25). Whole-tree water loss scaled to ground surface area (1.9 ± 0.5 mm d−1) was within the range reported for adjacent low-stature vegetation. Conclusions: The results suggest that the multiple linear regression approach is superior to the non-linear Jarvis-type model, as this approach allows discrimination between the effects of RS and the effects of D on QS .

Kinetics of aerobic phenol biodegradation by the acidophilic and hyperthermophilic archaeon Sulfolobus solfataricus 98/2

Biodegradation of 51–745mgl−1 of phenol by a well-acclimatized strain of Sulfolobus solfataricus, a thermoacidophilic archaeon, was studied in batch experiments at 80°C and pH 3.2. Phenol inhibited growth and specific degradation rates (μ and qS). Fitting the experimental growth data with the Haldane model gave the following kinetic parameters: μ*=0.094h−1,KS=77.7mgl−1, Ki=319.4mgl−1 (R2=0.950). The true μmax, calculated from μ*, was 0.047h−1. A volumetric degradation rate (Vmax) was calculated by fitting the phenol consumption data with the Gompertz model. The value of Vmax increased with initial phenol concentration (Si) up to 14.4mgl−1h−1. The qS values, calculated from Vmax, were fitted with the Haldane equation, yielding qSmax of 0.110gg−1h−1. The yield factor (YX/S) depends on Si and reached a maximum of 0.83gg−1 at Si=93mgl−1.S. solfataricus 98/2 displayed low μmax and qSmax but a good tolerance to phenol (fairly high Ki, K′i, high YX/S). This ability to grow on and degrade phenol (93mgl−1<optimal Si<175mgl−1) at high temperature and low pH is unique and may be useful for removing phenol from hot acidic contaminated effluents. Other possible application could lie in the production of the enzymes involved in the key steps of phenol degradation provided the cloning of the enzymes-related genes in fast-growing mesophiles.

Fault zone Q values derived from Taiwan Chelungpu Fault borehole seismometers (TCDPBHS)

The attenuation factor, Q, at a fault zone is an important parameter for understanding the physical properties. In this study, we investigated the Q value of the Chelungpu Fault, the main rupture of the Mw 7.6 Chi-Chi earthquake, using the 7-level TCDP borehole seismometer array (TCDPBHS). The TCDPBHS was deployed at depths from 945 to 1270m throughout the 1999 ruptured slip zone at 1111m. Three borehole seismometers (BHS1–BHS3) were placed in the hanging wall, and the remaining three (BHS5–BHS7) were placed in the foot wall, with BHS4 near the slip zone. The configuration allowed us to estimate the Q-structure of the recent ruptured fault zone. In this study, we estimated Q values between BHS1 and BHS4, Qs1 (Qp1) at the fault zone and between BHS4 to 2km in depth, Qs4 (Qp4) beneath the fault zone. We utilized two independent methods, the spectral ratio and spectral fitting analyses, for calculating the Q value of Qs1 (Qp1) in order to provide a reliability check. After analyzing 26 micro-events for Qs and 17 micro-events for Qp, we obtained consistent Q values from the two independent methods. The values of Qs1 and Qp1 were 21–22 and 27–35, respectively. The investigation for the value of Qs4 was close to 45, and Qp4 was 85. These Qp and Qs values are quiet consistent with observations obtained for the San Andreas Fault at the corresponding depth. A low Qs1 value for the recent Chelungpu Fault zone suggests that this fault zone has been highly fractured. Qs values within the Chelungpu Fault, similar to those within the San Andreas Fault, suggest that the Q structure within the fault zone is sedimentary rock independent. However, the possible existence of fluids, fractures, and cracks dominates the attenuation feature in the fault zone.

Frequency-dependent body wave attenuation characteristics in the Kumaun Himalaya

We have analyzed a data set consisting of 23 well located local earthquakes to study the seismic attenuation characteristics of the Kumaun Himalaya region. These events were recorded at 9 digital seismic stations in this region during 2004–2008. The frequency-dependent attenuation of P and S waves are estimated using the extended coda-normalization method for the frequency range of 1.5, 3, 6, 8 and 12Hz. The values of QP and QS show a ubiquitous observation of frequency dependence for the studied frequencies. We obtained QP=(22±5)f(1.35±0.04) and QS=(104±10)f(1.3±0.03) by fitting a power-law frequency dependence model with the estimated values over the whole region. Both Q values indicate a strong attenuation in the crust of Kumaun Himalaya. The ratio of QS/QP>1 obtained for the entire analyzed frequency range may suggest that the crust is characterized by a high degree of heterogeneity.

Inversion of borehole weak motion records observed in Istanbul (Turkey)

SUMMARY The estimation of shear wave velocity and attenuation in near-surface geology is of primary importance in engineering seismology. In fact, such knowledge is essential for site response studies when preparing improved seismic hazard scenarios. In this study, we propose a linear inversion of the spectra of a deconvolved wavefield collected by a borehole array in Istanbul, Turkey. The spectra are calculated using as a reference the recordings collected by a sensor at the surface. This allows us to minimize the effect of the deconvolution filter on the peaks’ amplitudes. The feasibility of the proposed inversion scheme and the parametrization of the velocity and attenuation models were tested and assessed using synthetic data. The real data inversion is carried out using observation from three weak motion events. Several starting models are used for each event, changing the values of the quality factor Qs, whereas the starting Vs profiles are fixed to what was obtained by the analysis of the deconvolved wavefield in the time domain. Our results showed that fairly well-constrained Vs models can be obtained while the variability of the Qs profile, both between different inversions of the same data set, and between the inversions of different data sets, might be large. This indicates that Qs variations observed in models derived by strong motion data inversions should be considered with care. However, the high agreement of the estimated soil profiles in the uppermost layer, both when using different events and different starting models, suggests that any variation in the S-wave velocity that might be estimated when using strong motion data should be reliable.

Structural and hyperfine properties of Ni-doped SnO2 nanoparticles

In this work, we report on the study of Ni-doped SnO2 nanoparticles prepared by a polymer precursor method. X-ray diffraction (XRD) data analysis evidenced the formation of only the tetragonal rutile-type phase in all samples. Meanwhile, the mean crystallite size shows a progressive reduction with the Ni content, the unit cell volume and residual strain does not show any clear dependence on the Ni content. Room temperature Mossbauer spectra were well modeled by using two doublets which represent the particle core and shell surface regions. Assuming that the isomer shift (IS) of the core region remains constant for all samples, the isomer shift of the shell region shows a linear increase with the Ni content. That increase was assigned to the progressive increase in the s-electronic density produced by either the generation of oxygen vacancies or the formation of Ni complexes at the surface due to the surface segregation of Ni ions as the Ni content is increased. Larger QS values obtained for the doublet of the shell are associated with the stronger distortions in the nearest surrounding of tin atoms produced by the surface segregation of Ni ions.

Microneedle technique in promoting transdermal delivery of arbutin

Objective To study the promoting effects of microneedle arrays on transdermal delivery of arbutin by comparing with the effect of chemical penetration enhancer azone.Methods The microneedles were fabricated with single-crystal Si as starting material using a series of photolithography,thin-film deposition,and reactive ion etching techniques.Franz-cells were used in the transdermal delivery experiment with human abdominal skin.The study was divided into the following 3 groups: the microneedle group(arbutin hydrogel without penetration enhancer,and the skin was treated with microneedle arrays);the control group(arbutin hydrogels containing 1%,3%,and 5% azone(W/V),and the skin received no microneedle treatment);and blank control group(arbutin hydrogel without azone,and the skin received no microneedle treatment).Arbutin levels in the receptor solution,epidermis and dermis were determined by HPLC at 1,3,6,12,24,36 and 48 h.The analyses were performed with a C18 column(250 mm × 4.6 mm,5 μm),at room temperature,mobile phase methanol∶1 ×10-3mol/ml HCl solution(V/V,5∶95),flow rate 1 ml/min,and detective wavelength 282 nm.The accumulative penetration amount(Qr),steady-state flux(Js) and the accumulative deposition amount(Qs) were calculated.Results The microneedles could pass the human skin.The standard curve was: C = 0.000 2A-0.182 9(r = 0.999 9),0.4-50 μg/ml.The RSD values of intraday and interday precisions were 2.4% and 2.74%,respectively;and the recovery was higher than 90%.The values of Qr,Js,and Qs in the microneedle group were significantly higher than those in the 5% azone group(P 0.01).Conclusion Microneedles can greatly promote the skin permeability and deposition of arbutin.

One-electron oxidized product of difluoroiron(iii) porphyrin: is it iron(iv) porphyrin or iron(iii) porphyrin π-cation radical?

The electronic structure of [Fe(TMP)F(2)], which is formally a one-electron oxidation equivalent above [Fe(III)(TMP)F(2)](-), has been examined in solution by (1)H NMR, UV-Vis, and Mössbauer spectroscopy. In CD(2)Cl(2)-CD(3)OD solution at 193 K, the pyrrole-H and m-H signals appeared at 128.2 and 116.7 ppm, respectively. The UV-Vis spectrum showed broad absorption bands at 560-680 nm. The Mössbauer spectrum taken in frozen toluene-methanol solution exhibited a very broad single line from which the IS and QS values were determined by computer simulation to be 0.50 and 0.14 mm s(-1), respectively. On the basis of these results, it was concluded that the one-electron oxidized product of [Fe(TMP)F(2)](-) should be formulated as the iron(III) radical cation [Fe(III)(TMP˙)F(2)], not as iron(IV) porphyrin [Fe(IV)(TMP)F(2)] as previously suggested.

The c-axis oriented AlN solidly mounted resonator operated in thickness shear mode using lateral electric field excitation

The AlN-based solidly mounted resonator operated in thickness shear mode using lateral field excitation is presented both in theory and experiment. The resonator configuration consists of the electrodes parallel to the surface, a highly c-oriented AlN film and an acoustic Bragg reflector. The theoretical analysis of the Christoffel equation predicts that the electric field in any direction normal to the c-axis can excite the shear mode wave along the thickness direction. The electric field characteristics are calculated by finite element modeling in order to design the electrode frame. The testing results of the finished devices show that the thickness shear mode wave can be excited by the lateral electric field in c-axis oriented AlN solidly mounted resonators. The experimental frequency corresponds well to the theoretical one. The resonators operated in thickness shear mode have resonant frequencies near 2 GHz with an average Qs value of 323 and a \(K_{\mathrm{eff}}^{2}\) value of 0.83%.