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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第11期11卷 851-861页

作者： Qing-bin WANG Wen XU Qing-zhong XUE Wei-ai SU Department of Agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Shanghai Institute of Plant Physiology and Ecology Chinese Academy of Science Shanghai 200032 China School of Resource and Environment Management Guizhou College of Finance and Economics Guiyang 550004 China

Transgenic Brassica compestris *** plants expressing a choline oxidase(coda) gene from Arthrobacter globiformis were obtained through Agrobacterium tumefaciens-mediated *** the transgenic plants,coda gene expression and its product transportation to chloroplasts were detected by the enzyme-linked immunosorbent assay(ELISA) examination,immunogold localization,and 1 H-nuclear magnetic resonance( 1 H-NMR) . Stress tolerance was evaluated in the T3 plants under extreme temperature and salinity *** plants of transgenic line 1(L1) showed significantly higher net photosynthetic rate(Pn) and Pn recovery rate under high(45°C,4 h) and low temperature(1°C,48 h) treatments,and higher photosynthetic rate under high salinity conditions(100,200,and 300 mmol/L NaCl,respectively) than the wild-type *** enhanced tolerance to high temperature and high salinity stresses in transgenic plants is associated with the accumulation of betaine,which is not found in the wild-type *** results indicate that the introduction of coda gene from Arthrobacter globiformis into Brassica compestris *** could be a potential strategy for improving the plant tolerance to multiple stresses.

关键词： Brassica compestris L. spp. chinensis coda Stress Glycine betaine Net photosynthetic rate (Pn)

TRANSPORTATION THEORY OF MULTIPLE SCATTERING AND ITS APPLICATION TO SEISMIC coda WAVES OF IMPULSE SOURCE

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Science in China,Ser.B 1988年第12期31卷 1503-1514页

作者：尚铁樑高龙生 Department of Applied Physics Harbin Engineering University Institute of Geophysics State Seismological Bureau Beijing

The energy distribution of elastic waves in an infinite elastic medium with uniformly and randomly distributed scatterers has been researched. The scattering process is assumed to be isotropic and without conversions between wave types. We get the equation on the distribution of energe density in time and space covering single as well as multiple scattering. Taking physical symmetry of the field into account, it can be simplified. In the case of small earthquakes, the energy source of elastic waves can be assumed as a short pulse emitted isotropically at t=0. The first-order approximate solution in the 3-dimensional space can be obtained, and it is equivalent to Sato’s solution for single scattering. In the 2-dimensional space the complete analytical solution has been derived by the mathematical inductance which leads to a conclusion that the codas of surface waves can give the Q-factor related to intrinsic absorption. The equation obtained in this paper is more general.

关键词： coda scattering seismic wave maltiple scattering Q-factor.

Attenuation of coda waves in the SW of High-Atlas area, Morocco

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Geodesy and Geodynamics 2019年第4期10卷 297-306页

作者： Roumaissae Azguet Ghizlane Bouskri Youssef Timoulali Mimoun Harnafi Younes EL.Fellah Scientific Institute Mohamed V University in RabatMorocco Faculty of Science Mohammed V University in RabatMorocco Rural Engineering Department Institut agronomique et veterinaire hassan IIRabatMorocco

We investigate attenuation scattering and loss properties in Souss basin(SW of High-Atlas) as a transition zone between the High and Anti Atlas ranges. This district consists in a thinned crustal patch with shallow seismicity and loose sedimentary trenches that perform an important contribution to augment seismic attenuation. So far, no coda waves approach in our knowledge have been used to draw satisfying outputs about the attenuation properties in the region. Therefore, this update suggests to correlate the lateral changes of seismic attenuation to different characteristics and asperities i.e. seismic activity,crustal age and thickness, heat flow, and ground deformation rate. To do so, we analysed coda waves derived from waveform data of more than 23 local earthquakes from seven broadband seismometers recorded during 2010 e2012 period. As a starter, we utilized the backscattering model which defines theseismic attenuation as inversely proportional to quality factor by the equation A ?1=. QQcestimates c were deducted at various central frequency bands 1.5, 3.0, 6.0, 9.0, 12.0 and 18.0 Hz according to different lapses times. The estimated average frequency dependence quality factor gives relation Qc? 120 f1;01,while the average Qcvalues vary from 149 at 1.5 Hz to 1895 at 18 Hz central frequencies. We observed an intimate dependence between quality factor and frequency ranges, which reflects the complexity of geological/geophysical pattern in the Souss basin and the presence of a variety of heterogeneities within the underlying crust.

关键词： Attenuation coda waves Quality factor Frequency Souss basin Morocco

A single-station coda solution for source,attenuation and site factors

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Acta Seismologica Sinica(English Edition) 1998年第2期11卷 30-37页

作者：张天中马云生黄蓉良

ased on the empirical formulation formed from coda observations, the digital waveforms from 33 local events with magnitude ML ranging between 2.1 and 3.5, recorded at Changli station of Beijing Telemetered Seismographic Network from 1989 to 1991, are used to compute coda Q for the Changli region and the source factors of all earthquakes by single-station coda method. Furthermore, assuming a certain source model, we have obtained the station site frequency response and source spectra, as well as source parameters such as corner frequencies, seismic moments and stress drops and so on. Their variations with time are monitored before and after larger earthquakes. Because the coda method can more effectively reduce the influence of source radiation pattern and a particular propagation path than direct wave method, more data can be used and more accurate results can be obtained, which provided a possible approach to study the source properties and reveal the variation of source parameters before larger earthquakes.

关键词： coda source factor hypocenter parameter stress drop precursor

Attenuation of coda waves and Q_c value beneath the Chengdu telemetered seismic network

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Acta Seismologica Sinica(English Edition) 1997年第3期10卷 26-33页

作者：曾健陈天长韩渭宾范军郑斯华长谷川昭堀内茂木松本聪

Based on the single scattering model of coda power spectrum analysis, digital waveform data of 50 events recorded by the real time processing system of the Chengdu telemetry network are analyzed to estimate the Q c values of earth medium beneath the Chengdu telemetry network for several specified frequencies. It is found that the Q c shows the frequency dependency in the form of Q c= Q 0 f n in the range of 1.0 to 20.0Hz. Estimated Q 0 ranges from 60.83 to 178.05, and n is found to be 0.713 to 1.159. The average value of Q 0 and n are 117 and 0.978 respectively. This result indicates the strong frequency dependency of the attenuation of coda waves beneath the Chengdu telemetry network. Comparing with the results obtained in other regions of the world, it is found that Q 0 1 value and its change with frequency are similar to those in regions with strong tectonic activity.

关键词： Chengdu telemetered network coda Q frequency dependency tectonic activity

Monitoring Contact State of Laboratory Fault with coda Transmission Waves

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Earthquake Research in China 2019年第3期33卷 431-436页

作者： XIE Fan REN Yaqiong HOU Jinxin Institute of Geophysics China Earthquake Administration

We monitored the amplitude changes of coda transmission waves around 500 kHz across the frictional interface of a simulated 1. 5-meter-long fault during normal stress holding *** find that the amplitude of coda transmission waves increases with the logarithm of stationary contact time. Localized increase amounted to a level ranging from 4% to 16%along the fault is observed during the 1-hour experiment. We discuss that the frictional strength at mesoscopic scale,which is related to the amplitude of coda transmission waves,is responsible for the phenomenon. Combining the reported method with other complementary approaches will enhance the understanding of fault mechanism either at laboratory or on-site applications.

关键词： coda transmission waves Laboratory fault Frictional contact area

Investigation on the Load/Unload Response Ratio With coda Q-1 as Response

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Earthquake Research in China 1996年第4期10卷 38-45页

作者： Chen Xuezhong,Yin Xiangchu,Aki K,Ouyang H,Jin A.,Song Zhiping,and Wang YucangCenter tor Analysis and Prediction,SSB,Beijing 100036,ChinaSouthern California Eanhquake Center,University of Southern California,Los Angeles,USAInstitute of Geophysics,SSB,Beijing 100081,China

The load/unload response ratio YQ with the geophysical parameter coda Q-1 of the crust as response is denned in this *** variation in YQ-1 before and after the Northridge earthquake of January 17,1994(California)has been investigated by using the data of coda Q-1 with frequencies of 1.5,3.0,6.0,12.0,and 24.0 Hz in the Southern California from 1987 to *** can be found that YQ-1 for coda waves with all frequencies,the frequency of 12.0 Hz excluded,ascended to a certain extent prior to the occurrence of the rnainshock and returned to normality after the main shock.

关键词： coda Q-1 Theory of the load/unload response ratio Load/unload response ratio YQ The Northridge earthquake Earthquake prediction

Spatial variation of coda wave attenuation using aftershocks of the Al Hoceima earthquake of 24 February, 2004, Morocco

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Natural Science 2013年第8期5卷 72-77页

作者： Abderrahim Boulanouar Lahcen El Moudnib Mimoun Harnafi Taj-Eddine Cherkaoui Abdelaali Rahmouni Mohamed Boukalouch Jamal Sebbani Earth Science Department Scientific Institute Mohammed V University-Agdal Rabat Morocco Physics Department Faculty of Science Mohammed V University-Agdal Rabat Morocco Physics Department Faculty of Science Mohammed V University-Agdal Rabat Morocco Earth Science Department Scientific Institute Mohammed V University-Agdal Rabat Morocco

On 24th February 2004 a significant earthquake (Md = 6.4) occurred in the north of Moroccocausing great damage in the vicinity of Al Hoceima region. This area is characterized by a complex faulting system as a result of compressional tectonic forces. Three short period seismic stations are set in this area of interest and recordings from these stations were used in this study. In order to complete our knowledge of attenuation, 60 local earthquakes are recorded a few days after the great earthquake with magnitude Ml 2.6 - 5.0 to estimate seismic attenuation. For this purpose, we applied the single backscattering model of Aki & Chouet 1975 inthe frequency range for 1 to 8 Hz. The study of coda waves was limited to a relatively short lapse time (20 Seconds) in order to sample the earth’s crust only. The values of Qc estimated for all the three stations show a strong frequency dependent relationship of the form Qc = Q0fn, where Q0 is Qc at 1 Hz , and n represents the degree of frequency dependence, and reflects the level of crustal heterogeneities to varying degrees. The average frequency dependent attenuation relationship has been obtained which indicates that the attenuation is high in this region. Finally to conclude our work, the values of Q0 suggest that Al Hoceima area is highly heterogeneous and the n parameter indicates a meaning frequency dependence of Qc.

关键词： Attenuation coda Waves Single Backscattering Model Al Hoceima Morocco Seismic Earthquake

Analysis on the Regional Features of coda Attenuation Before and After the 1992 Qina (M_S= 5.4, 5.1) Earthquakes in WYEPSA

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Earthquake Research in China 1996年第2期10卷 47-58页

作者： Qin Jiazheng, Liu Zuyin, and Long Xiaofan Seismological Bureau of Yunnan Province, Kunming 650041, China

Using the theoretical model of coda scattering from local earthquakes, we have studied the features of time-space variations of the attenuation rate β of coda amplitude and coda Qc-1 values before and after the Qina earthquakes (MS5.4 and MS5.1) in Dec. 1992 in West Yunnan Earthquake Prediction Study Area (WYEPSA). The study results show that the attenuation rate of coda amplitude has remarkable regional inhomogeneity in the near-field (△ coda attenuation in surrounding areas (△ > 50 km) far away from the epicenter of the main shock did not change much before and after the main shock. The evolution of Qc-1 values of the main seismic sequence with time has passed

关键词： Anomalous character Q value method of the coda wave Earthquake precursor Western-Yunnan seismological experiment site

Transformation coda Gene to Lily Plants by Agrobacterium tumefaciences Mediated

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Journal of Agricultural Science and Technology(B) 2018年第6期8卷 375-381页

作者： Bui Thi Thu Huong Dong Huy Gioi Le Tran Binh Faculty of Biotechnology Vietnam National University of AgricultureTrau QuyGia Lam 12406HanoiVietnam Institute of Biotechnology Vietnam Academy of Science and TechnologyNghia TanCau Giay 11308HanoiVietnam

Glycinebetaine(GB),an osmotic substance,could improve some stress tolerance in *** gene,originating from bacteria,could translate choline oxidase which stimulates the synthesis of GB in *** create lily lines resistant to heat,Belladonna lily and Yelloween lily had been transferred coda gene through Agrobacterium *** bacteria harbored a binary vector carrying the hygromycin phosphotransferase,choline oxidase(coda)and intron-containingβ-glucuronidase(Gus)genes were co-cultivated with lily bulb scales *** result showed that most the bulb scales had developed into bulblets in a regulator-free growth medium,while some expressed the hygromycin-resistance,heat tolerance and Gus gene *** them,one line demonstrated primarily the transcription level expression through reverse transcription polymerase chain reaction(RT-PCR).Moreover,they were tested with the accumulation of GB which was evident that the transferred line had four times of GB volumes higher than that of wild *** original evidence could open a right approach to enhance stress tolerance in lily plants.

关键词： Agrobacterium tumefaciens coda gene genetic transformation glycinebetaine lily stress tolerance in plants