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Growth performance and physiological parameters of the second generation selected and control groups of Pinctada martensii 被引量:10
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作者 DENG Yuewen YU Ziniu +2 位作者 DU Xiaodong WANG Qingheng FU Shao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期120-125,共6页
In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the... In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the first generation selected group.Growth performance of the SS and SC groups were compared on the basis of measurement data at Days 8,18,60,95,195 and 365.On Day 365,100 individuals (60.0–75.0 mm at shell length) were sampled from each group and then subjected to the experiment where physiological parameters such as filtrate rate,oxygen consumption and ammonia excretion were measured at 15,20,25 and 30°C.The results show that the SS group had significantly larger mean shell length and shell height than the SC group at Days 8,18,60,95,195 and 365 (P 0.05).The genetic gains at different ages varied from 6.0% to 17.0% for shell length and 5.7% to 14.6% for shell height,respectively.At 15,20,25 and 30 ° C,the SS groups had significantly larger filtrate rate than the SC group (P 0.05).At 15 and 25 °C,the differences in oxygen consumption rate between the SS and SC groups were not significant (P 0.05).At 20 and 30 °C,however,the oxygen consumption rate of the SS group was significantly larger than the SC group (P 0.05).At 15,20,25 and 30 °C,there were no significant differences in ammonia excretion rate between the SS and SC groups (P 0.05).The present results indicate that there existed considerable genetic variability in the base population and a further selection could be likely fruitful.Mass selection for faster growth might produce animals that had higher intake of metabolizable energy by virtue of faster filtrating behavior. 展开更多
关键词 Pinctada martensii the second generation selected group GROWTH genetic gains physiological parameters
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Response to Selection for Fast Growth in the Second Generation of Pacific Oyster (Crassostrea gigas) 被引量:15
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作者 WANG Qingzhi LI Qi +1 位作者 KONG Lingfeng YU Ruihai 《Journal of Ocean University of China》 SCIE CAS 2012年第3期413-418,共6页
Mass selection for fast growth was conducted in three Pacific oyster (Crassostrea gigas) stocks from China, Japan and Korea using previously established lines (CS1, JS1, and KS1). To determine whether continuous progr... Mass selection for fast growth was conducted in three Pacific oyster (Crassostrea gigas) stocks from China, Japan and Korea using previously established lines (CS1, JS1, and KS1). To determine whether continuous progress can be achieved by selection for growth, the progeny of three second-generation Pacific oyster lines was selected for shell height and evaluated via a 400-day farming experiment. When harvested at the end of the experiment, the selected crosses of CS2, JS2, and KS2 lines grew by 9.2%, 10.2% and 9.6% larger than the control crosses, respectively. During grow-out stage, the genetic gain of three selected lines was (10.2 ± 1.4)%, (10.4 ± 0.3)%, and (8.4 ± 1.6)%, respectively; and the corresponding realized heritability was 0.457 ± 0.143, 0.312 ± 0.071 and 0.332 ± 0.009, respectively. These results indicated that the selection for fast growth achieved steady progress in the second generation of oyster. Our work provides supportive evidence for the continuity of the Pacific oyster selective breeding program. 展开更多
关键词 Pacific oyster Crassostrea gigas mass selection second generation genetic gain realized heritability
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The surface wave suppression using the second generation curvelet transform 被引量:11
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作者 郑静静 印兴耀 +2 位作者 张广智 武国虎 张作胜 《Applied Geophysics》 SCIE CSCD 2010年第4期325-335,399,400,共13页
In this paper,we develop a new and effective multiple scale and strongly directional method for identifying and suppressing ground roll based on the second generation curvelet transform.Making the best use of the curv... In this paper,we develop a new and effective multiple scale and strongly directional method for identifying and suppressing ground roll based on the second generation curvelet transform.Making the best use of the curvelet transform's strong local directional characteristics,seismic frequency bands are transformed into scale data with and without noise.Since surface waves and primary reflected waves have less overlap in the curvelet domain,we can effectively identify and separate noise.Applying this method to prestack seismic data can successfully remove surface waves and,at the same time,protect the reflected events well,particularly in the low-frequency band.This indicates that the method described in this paper is an effective and amplitude-preserving method. 展开更多
关键词 second generation curvelet transform multiscale strong directional characteristics surface wave removal
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Effects of the second-generation larch plantations onsoil fertility and tree growth
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作者 王培华 席苏桦 +2 位作者 姜文娟 刘亚彬 孙玉英 《Journal of Forestry Research》 CAS CSCD 2000年第1期41-43,共3页
In order to realize the effect of second generation of larch plantations on soil fertility and tree growth and to provide the theoretical base and the reasonable management measures, the growth of larch plantations fo... In order to realize the effect of second generation of larch plantations on soil fertility and tree growth and to provide the theoretical base and the reasonable management measures, the growth of larch plantations for different generations at different soil conditions were inventoried and compared. The relationship between soil nutrition and tree growth of the second-generation larch plantations was analyzed. Comparing with the first generation, the second generation of larch did not present acidation phenomenon on the dark brown soil. With respect to the organic matter, rapidly available K and N, the values of the second-generation larch is close to that of first generation at later time. Platform-preparation is good measures for improving soil conditions 展开更多
关键词 Larch plantation second generation Soil fertility GROWTH Standing trees
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Modulation of the second-harmonic generation in MoS_(2) by graphene covering
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作者 Chunchun Wu Nianze Shang +9 位作者 Zixun Zhao Zhihong Zhang Jing Liang Chang Liu Yonggang Zuo Mingchao Ding Jinhuan Wang Hao Hong Jie Xiong Kaihui Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期144-149,共6页
Nonlinear optical frequency mixing,which describes new frequencies generation by exciting nonlinear materials with intense light field,has drawn vast interests in the field of photonic devices,material characterizatio... Nonlinear optical frequency mixing,which describes new frequencies generation by exciting nonlinear materials with intense light field,has drawn vast interests in the field of photonic devices,material characterization,and optical imaging.Investigating and manipulating the nonlinear optical response of target materials lead us to reveal hidden physics and develop applications in optical devices.Here,we report the realization of facile manipulation of nonlinear optical responses in the example system of MoS_(2) monolayer by van der Waals interfacial engineering.We found that,the interfacing of monolayer graphene will weaken the exciton oscillator strength in MoS_(2) monolayer and correspondingly suppress the second harmonic generation(SHG)intensity to 30%under band-gap resonance excitation.While with off-resonance excitation,the SHG intensity would enhance up to 130%,which is conjectured to be induced by the interlayer excitation between MoS_(2) and graphene.Our investigation provides an effective method for controlling nonlinear optical properties of two-dimensional materials and therefore facilitates their future applications in optoelectronic and photonic devices. 展开更多
关键词 two-dimensional materials second harmonic generation(SHG) GRAPHENE dielectric screening
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QM/MM Study of the Second Harmonic Generation and Two-photon Absorption Properties of a Fluorescent Proteins-Dreiklang
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作者 张敏熠 魏婧 +2 位作者 宋金帅 吴鹏 李春森 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第9期1393-1403,共11页
A new reversibly switchable fluorescent protein(RSFP), namely Dreiklang, exhibits prominent feature that the wavelengths for switching and fluorescence are decoupled due to its great different structures between bri... A new reversibly switchable fluorescent protein(RSFP), namely Dreiklang, exhibits prominent feature that the wavelengths for switching and fluorescence are decoupled due to its great different structures between bright and dark states. This feature might also induce some nonlinear optic(NLO) properties changing as switching between two states, which might promote new method of biological science. We employ the QM/MM method to simulate the structures of different states, and study their second harmonic generation(SHG) and two-photon absorption(TPA) properties. And we found different states of Dreiklang have different SHG and TPA responses. The SHG and TPA properties of Dreiklang are correlated to particularly geometrical structures of different states, especially the centrosymmetric or nocentrosymmetric π-stacking structures which are formed by chromophore and beside residue Tyr203, so the SHG and TPA responses could be changed as the light induces switching among different states of Dreiklang. This work would prospectively guide the application of Dreiklang on the NLO technology, and help the development of new RSFP with special NLO function. 展开更多
关键词 fluorescent proteins the second harmonic generation two-photon absorption QM/MM method
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Second Law Analysis of the Optimal Fin by Minimum Entropy Generation
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作者 苏亚欣 周睿杰 《Journal of Donghua University(English Edition)》 EI CAS 2005年第4期25-28,共4页
Based on the entropy generation concept of thermodynamics, this paper estabfished a general theoretical model for the analysis of entropy generation to optimize fins, in which the minimum entropy generation was select... Based on the entropy generation concept of thermodynamics, this paper estabfished a general theoretical model for the analysis of entropy generation to optimize fins, in which the minimum entropy generation was selected as the object to be studied. The irreversibility due to heat transfer and friction was taken into account so that the minimum entropy generation number has been analyzed with respect to second law of thermodynamics in the forced cross-flow. The optimum dimensions of cylinder pins were discussed. It's found that the minimum entropy generation number depends on parameters related to the fluid and fin physical parameters. Varlatioms of the minimum entropy generation number with different parameters were analyzed. 展开更多
关键词 forced convective heat transfer minimum entropy generation second law analysis pin fin.
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Second-Generation Muslim Youth Between Perception and Change: A Case Study on the Prevention of Radicalization
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作者 Marilena Macaluso Giuseppina Tumminelli +1 位作者 Angelica Spampinato Andrea Volterrani 《Sociology Study》 2020年第3期103-122,共20页
The following article presents the results of a research-action and an online communication campaign on the prevention of radicalization of second-generation young Italian Muslims as a part of a project called“Oltre... The following article presents the results of a research-action and an online communication campaign on the prevention of radicalization of second-generation young Italian Muslims as a part of a project called“Oltre”(the Italian acronym means“Beyond”)financed by European Union.After a short presentation of the four steps of the prevention communication model PKIC,a deepening on the radicalization factors,and a focus on the research-action methodology,the results of the research on some fundamental issues like the relationship with family and the relation with media and social media of the young interviewees,are shown.Finally,in the last part of the article,the interventions carried out by the second-generation young moderators of the social media campaign carried on Facebook and Instagram,are presented in the framework of the online communication campaign born out of the research-action to discuss if and how a prevention process and consequent change with regard to the radicalization factors took place. 展开更多
关键词 PREVENTION RADICALIZATION second generation IDENTITY family media social media
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An Investigation into the Role of Capping on Second Harmonic Generation from Nonlinear Organic Polymer and Guest-Host Thin Films by In-Situ Poling
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作者 P. M. Ushasree M. Szablewski 《Optics and Photonics Journal》 2016年第5期101-111,共11页
In attempts to fabricate thermally stable second-order nonlinear polymer thin films, we have investigated the second harmonic generation (SHG) from both nonlinear polymer and guest-host thin films. We have also invest... In attempts to fabricate thermally stable second-order nonlinear polymer thin films, we have investigated the second harmonic generation (SHG) from both nonlinear polymer and guest-host thin films. We have also investigated the role of capping on the SHG, temporal stability and relaxation of dipole alignment. Corona poling techniques were employed to orient the dopants into the noncentrosymmetric structure required to obtain the SHG. The effect of capping with a polymeric encapsulant below the glass transition temperature of the polymers on the unpoled and corona poled thin films was studied. Capping of the nonlinear polymer and guest host thin films have resulted in high SHG with good temporal stability. SHG signal falls drastically during the first 8 days after poling while no further significant decay in SHG signal was observed after about 33 days. Our investigations have identified the characteristics required for a good encapsulant on a non-con-ductive surface. 展开更多
关键词 second Harmonic generation Nonlinear Polymer Thin Films Guest-Host Thin Films Capping Temporal Stability Corona Poling
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Dual bound states in the continuum enhanced second harmonic generation with transition metal dichalcogenides monolayer 被引量:2
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作者 Peilong Hong Lei Xu Mohsen Rahmani 《Opto-Electronic Advances》 SCIE EI CAS 2022年第7期16-23,共8页
The emergence of two dimensional(2D)materials has opened new possibilities for exhibiting second harmonic genera-tion(SHG)at the nanoscale,due to their remarkable optical response related to stable excitons at room te... The emergence of two dimensional(2D)materials has opened new possibilities for exhibiting second harmonic genera-tion(SHG)at the nanoscale,due to their remarkable optical response related to stable excitons at room temperature.However,the ultimate atomic-scale interaction length with light makes the SHG of Transition Metal Dichalcogenides(TM-Ds)monolayers naturally weak.Here,we propose coupling a monolayer of TMDs with a photonic grating slab that works with doubly resonant bound states in the continuum(BIC).The BIC slabs are designed to exhibit a pair of BICs,reson-ant with both the fundamental wave(FW)and the second harmonic wave(SHW).Firstly,the spatial mode matching can be fulfilled by tilting FW's incident angle.We theoretically demonstrate that this strategy leads to more than four orders of magnitude enhancement of SHG efficiency than a sole monolayer of TMDs,under a pump light intensity of 0.1 GW/cm^(2).Moreover,we demonstrate that patterning the TMDs monolayer can further enhance the spatial overlap coefficient,which leads to an extra three orders of magnitude enhancement of SHG efficiency.These results demonstrate remarkable pos-sibilities for enhancing SHG with nonlinear 2D materials,opening many opportunities for chip-based light sources,nano-lasers,imaging,and biochemical sensing. 展开更多
关键词 second harmonic generation transition metal dichalcogenides bound state in the continuum photonic grating slab
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The Lifting Scheme Based on the Second Generation Wavelets 被引量:1
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作者 FENG Hui GUO Lanying XIAO Jinsheng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期503-506,共4页
The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing t... The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing time with its particular frame. This paper aims at introducing the second generation wavelets, begins with traditional Mallat algorithms, illustrates the lifting scheme and brings out the detail steps in the construction of Biorthogonal wavelets. Because of isolating the degrees of freedom remaining the biorthogonality relations, we can fully control over the lifting operators to design the wavelet for a particular application, such as increasing the number of the vanishing moments. 展开更多
关键词 lifting scheme the second generation wavelets vanishing moments
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Maternal Separation Affects Mothers’ Affective and Reproductive Behaviors as Well as Second Offspring’s Emotionality 被引量:1
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作者 R. Bousalham B. Benazzouz +2 位作者 A. El Hessni A. Ouichou A. Mesfioui 《Journal of Behavioral and Brain Science》 2013年第5期409-414,共6页
Daily separation of rat pups from their mothers while the preweaning period has an impact on behavior and stress response of pups. We hypothesized that maternal separation may create a depression-like state in mother ... Daily separation of rat pups from their mothers while the preweaning period has an impact on behavior and stress response of pups. We hypothesized that maternal separation may create a depression-like state in mother rats from which we separate the rat pups and decrease their reproductive function and fertility. Also, we aimed to evaluate the transmission degree of depression and anxiety across generations. Females aged 3 months were divided in two groups of 10 rats each. After a first mating and a first parturition, we conducted maternal separation 3 h during 22 days for the experienced group while the control group mothers kept their pups. At 4 months of age, females underwent behavioral tests and a second mating. Second generation’s pups were also subjected to behavioral tests. Behavioral tests showed that mothers which experienced separation were more depressive and anxious than control ones, also they had a lower litter size. Rats pups of the second generation whose mothers experienced maternal separation also revealed behavior changes akin to depression and anxiety. Thus, maternal separation causes depressive and anxious-likestates on mother rats which experienced separation and has an impact on their litter size. Also, consequences of maternal separation seem to last throughout generations. 展开更多
关键词 MATERNAL Separation AFFECTIVE Disorder Mothers’ Rat Reproduction ofFSPRING of second generation
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Becoming Adults During an Economic Crisis: What Happens to the Second Generations?
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作者 Roberta Ricuccia 《Sociology Study》 2013年第10期752-762,共11页
The paper presents findings of an empirical study carried out in an Italian area and focused on the effects of the economic crisis on immigrant families: the goal was to identify how the difficulties of these years ... The paper presents findings of an empirical study carried out in an Italian area and focused on the effects of the economic crisis on immigrant families: the goal was to identify how the difficulties of these years (not only socio-economic but also in terms of negative attitudes toward immigrants) affect on the life-paths of second generations. What happens to their school career? Are they forced to leave school in order to improve the family's income? Are they sent back to the country of origin of their parents to reduce life-costs in the immigration country? Thanks to a collection of around 30 interviews with young people between 18-24 years old and 30 interviews with both parents and social workers, the strategies which families are choosing to face economic and labour difficulties and their effects on integration paths and inter-ethnic relations will be described. 展开更多
关键词 Economic crisis the second generations INTEGRATION MIGRATION
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Adaptive Wavelets Based on Second Generation Wavelet Transform and Their Applications to Trend Analysis and Prediction
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作者 DUANChen-dong JIANGHong-kai HEZheng-jia 《International Journal of Plant Engineering and Management》 2004年第3期170-176,共7页
In order to make trend analysis and prediction to acquisition data in amechanical equipment condition monitoring system, a new method of trend feature extraction andprediction of acquisition data is proposed which con... In order to make trend analysis and prediction to acquisition data in amechanical equipment condition monitoring system, a new method of trend feature extraction andprediction of acquisition data is proposed which constructs an adaptive wavelet on the acquisitiondata by means of second generation wavelet transform ( SGWT), Firstly, taking the vanishing momentnumber of the predictor as a constraint, the linear predictor and updater are designed according tothe acquisition data by using symmetrical interpolating scheme. Then the trend of the data isobtained through doing SGWT decomposition , threshold processing and SGWT reconstruction. Secondly,under the constraint of the vanishing moment number of the predictor, another predictor based on theacquisition data is devised to predict the future trend of the data using a non-symmetricalinterpolating scheme, A one-step prediction algorithm is presented to predict the future evolutiontrend with historical data. The proposed method obtained a desirable effect in peak-to-peak valuetrend analysis for a machine set in an oil refinery. 展开更多
关键词 second generation wavelet transform ( SCWT) PREDICTOR updater trendanalysis trend prediction
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Second Harmonic Generation of Lamb Wave in Numerical Perspective 被引量:2
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作者 朱武军 邓明晰 +2 位作者 项延训 轩福贞 刘长军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期71-74,共4页
The influences of phase and group velocity matching on cumulative second harmonic generation of Lamb waves are investigated in numerical perspective. Finite element simulations of nonlinear Lamb wave propagation are p... The influences of phase and group velocity matching on cumulative second harmonic generation of Lamb waves are investigated in numerical perspective. Finite element simulations of nonlinear Lamb wave propagation are performed for Lamb wave mode pairs with exact and approximate phase velocity matching, with and without group velocity matching, respectively. The evolution of time-domain second harmonic Lamb waves is analyzed with the propagation distance. The amplitudes of primary and second harmonic waves are calculated to characterize the acoustic nonlinearity. The results verify that phase velocity matching is necessary for generation of the cumulative second harmonic Lamb wave in numerical perspective, while group velocity matching is demonstrated to not be a necessary condition. 展开更多
关键词 of on MODE second Harmonic generation of Lamb Wave in Numerical Perspective in IS for PAIR
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Projecting future precipitation change across the semi-arid Borana lowland,southern Ethiopia
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作者 Mitiku A WORKU Gudina L FEYISA +1 位作者 Kassahun T BEKETIE Emmanuel GARBOLINO 《Journal of Arid Land》 SCIE CSCD 2023年第9期1023-1036,共14页
Climate change caused by past,current,and future greenhouse gas emissions has become a major concern for scientists in the field in many countries and regions of the world.This study modelled future precipitation chan... Climate change caused by past,current,and future greenhouse gas emissions has become a major concern for scientists in the field in many countries and regions of the world.This study modelled future precipitation change by downscaling a set of large-scale climate predictor variables(predictors)from the second generation Canadian Earth System Model(CanESM2)under two Representative Concentration Pathway(RCP)emission scenarios(RCP4.5 and RCP8.5)in the semi-arid Borana lowland,southern Ethiopia.The Statistical DownScaling Model(SDSM)4.2.9 was employed to downscale and project future precipitation change in the middle(2036-2065;2050s)and far(2066-2095;2080s)future at the local scale.Historical precipitation observations from eight meteorological stations stretching from 1981 to 1995 and 1996 to 2005 were used for the model calibration and validation,respectively,and the time period of 1981-2018 was considered and used as the baseline period to analyze future precipitation change.The results revealed that the surface-specific humidity and the geopotential height at 500 hPa were the preferred large-scale predictors.Compared to the middle future(2050s),precipitation showed a much greater increase in the far future(2080s)under both RCP4.5 and RCP8.5 scenarios at all meteorological stations(except Teletele and Dillo stations).At Teltele station,the projected annual precipitation will decrease by 26.53%(2050s)and 39.45%(2080s)under RCP4.5 scenario,and 34.99%(2050s)and 60.62%(2080s)under RCP8.5 scenario.Seasonally,the main rainy period would shift from spring(March to May)to autumn(September to November)at Dehas,Dire,Moyale,and Teltele stations,but for Arero and Yabelo stations,spring would consistently receive more precipitation than autumn.It can be concluded that future precipitation in the semi-arid Borana lowland is predicted to differ under the two climate scenarios(RCP4.5 and RCP8.5),showing an increasing trend at most meteorological stations.This information could be helpful for policymakers to design adaptation plans in water resources management,and we suggest that the government should give more attention to improve early warning systems in drought-prone areas by providing dependable climate forecast information as early as possible. 展开更多
关键词 future precipitation climate change second generation Canadian Earth System Model(CanESM2) Statistical DownScaling Model(SDSM) semi-arid Borana lowland southern Ethiopia
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Photoinduced Second Harmonic Generation of Bi_2S_3 Microcrystallite Doped Silica Glass 被引量:2
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作者 Letters Hongbing CHEN and Hai ping XIA Institute of Optoelectric Materials, Ningbo University, Ningbo 315211, China Congshan ZHU and Fuxi GAN Shanghai Institute of Optics & Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第5期565-566,共1页
Silica glasses doped with Bi2S3 microcystallite was prepared by the sol-gel process. Photoinduced second harmonic generation (SHG) was observed in the glass when it was irradiated with intense 1.06 mum and frequency d... Silica glasses doped with Bi2S3 microcystallite was prepared by the sol-gel process. Photoinduced second harmonic generation (SHG) was observed in the glass when it was irradiated with intense 1.06 mum and frequency doubled laser beams from a mode-locked Nd: YAG laser. It was found that the signal intensity increased with the irradiating time and approached a saturation gradually. The effect may be explained reasonably by the DC field model. 展开更多
关键词 SHG Photoinduced second Harmonic generation of Bi2S3 Microcrystallite Doped Silica Glass BI
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Generation of femtosecond laser pulses at 396 nm in K_3B_6O_(10)Cl crystal 被引量:1
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作者 张宁华 滕浩 +6 位作者 黄杭东 田文龙 朱江峰 吴红萍 潘世烈 方少波 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期262-265,共4页
K3B6O10Cl (KBOC), a new nonlinear optical crystal, shows potential advantages for the generation of deep ultraviolet (UV) light compared with other borate crystals. In this paper we study for the first time the se... K3B6O10Cl (KBOC), a new nonlinear optical crystal, shows potential advantages for the generation of deep ultraviolet (UV) light compared with other borate crystals. In this paper we study for the first time the second harmonic generation (SHG) of a femtosecond Ti:sapphire amplifier with this crystal. Laser power is obtained to be as high as 220 mW at the central wavelength of 396 nm with a 1-mm-long crystal, and the maximum SHG conversion efficiency reaches 39.3%. The typical pulse duration is 83 fs, The results show that second harmonic (SH) conversion efficiency has the room to be further improved and that the new nonlinear crystal is very suited to generate the high efficiency deep ultraviolet laser radiation below 266 nm. 展开更多
关键词 nonlinear optics nonlinear optical crystal second harmonic generation
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Generation of 15 W femtosecond laser pulse from a Kerr-lens mode-locked Yb:YAG thin-disk oscillator 被引量:2
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作者 彭英楠 张金伟 +3 位作者 王兆华 朱江峰 李德华 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期359-363,共5页
We demonstrated a robust power-scalable Kerr-lens mode-locked(KLM) operation based on a Yb:YAG thin-disk oscillator.15-W,272-fs pulses were realized at a repetition rate of 86.7 MHz with an additional Kerr medium a... We demonstrated a robust power-scalable Kerr-lens mode-locked(KLM) operation based on a Yb:YAG thin-disk oscillator.15-W,272-fs pulses were realized at a repetition rate of 86.7 MHz with an additional Kerr medium and a 2.5 mm hard aperture in the cavity.247-fs pulses with an average power of 11 W could also be obtained by using a 2.4 mm hard aperture.Based on this shorter pulse,high efficient second-harmonic generation(SHG) was performed with a 1.7-mm-long Li B3O5(LBO) crystal.The SHG laser power was up to 5 W with the power fluctuation RMS of 1% measured over one hour. 展开更多
关键词 thin disk Kerr-lens mode-locking high power second harmonic generation
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Generation of 160 nm vacuum ultraviolet light at 82 MHz in a KBBF crystal by the fifth-harmonic of a Ti:sapphire laser
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作者 张赟 汪丽蓉 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第5期95-99,共5页
We report the generation of quasi-cw vacuum ultraviolet(VUV)light at 160 nm with a repetition rate of 82 MHz by two second-harmonic generations and one sum frequency mixing.The VUV laser light is produced as a fifth-h... We report the generation of quasi-cw vacuum ultraviolet(VUV)light at 160 nm with a repetition rate of 82 MHz by two second-harmonic generations and one sum frequency mixing.The VUV laser light is produced as a fifth-harmonic generation of a mode-locked ps Ti:sapphire laser system by successive stages with nonlinear crystals of LBO and KBBF.A stable generation of laser light at 200 nm for more than 6 h is the most important step for obtaining the generation of light at a wavelength of 160 nm. 展开更多
关键词 vacuum ultraviolet light second harmonic generation sum frequency mixing
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