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Tb^(3+)在YAG中的发光及Tb^(3+)与Tm^(3 +)间的能量传递 被引量:6
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作者 周誓红 张思远 张静筠 《化学研究》 CAS 2000年第1期16-17,37,共3页
采用溶胶 -凝胶方法合成了系列化合物 (Y1 -x- yTbxTmy) 3Al5O1 2 ,研究了Tb3+在该化合物中的发光及其浓度对发光性质的影响 ,以及Tb3+与Tm3+间的能量传递现象。
关键词 发交 能量转移 YAG 合成 铽离子 锈离子
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斑茅F1品系崖城96-66与CP84-1198杂交后代的鉴别 被引量:8
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作者 杨业后 符成 +2 位作者 张垂明 邓海华 廖兆周 《甘蔗糖业》 2002年第4期11-14,共4页
对斑茅F1品系崖城96-66×CP84-1198杂交后代进行过氧化物酶和酯酶同工酶分析,并与父母本酶带作比较。结果表明,受检的20个株系中,除YCE01-62不具斑茅的特征酶带外,其它19个株系都具有斑茅的酶带,可初步认为是斑茅的第二代杂种。对其... 对斑茅F1品系崖城96-66×CP84-1198杂交后代进行过氧化物酶和酯酶同工酶分析,并与父母本酶带作比较。结果表明,受检的20个株系中,除YCE01-62不具斑茅的特征酶带外,其它19个株系都具有斑茅的酶带,可初步认为是斑茅的第二代杂种。对其中7个株系进行了DNA分子标记分析,结果显示除YCE01-62为杂株外,其它株系均确认为真杂种。在本研究中,同工酶方法的结果与DNA分子标记方法的结果相似。 展开更多
关键词 斑茅 杂交后代 鉴别 甘蔗 属间发交 同工酶 DNA分子标记
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粳杂80优9号高产制种技术四项辅助试验
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作者 刘平 《作物研究》 1997年第3期13-16,共4页
对粳型杂交稻80优9号制种时实施的“父本栽插苗数”、“父母本栽插行比”、“生物激素利用”和“父本氮肥深施”试验的结果表明,该组合高产制种父本以穴栽3粒种子苗为宜,最佳行比为2∶10,九二○用量为8g/667m2。分析... 对粳型杂交稻80优9号制种时实施的“父本栽插苗数”、“父母本栽插行比”、“生物激素利用”和“父本氮肥深施”试验的结果表明,该组合高产制种父本以穴栽3粒种子苗为宜,最佳行比为2∶10,九二○用量为8g/667m2。分析了父本深施氮肥必须注意的问题。 展开更多
关键词 发交水稻 制种 粳杂80优号
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Implementation of a 6 GHz band TDD RF transceiver for the next generation mobile communication system 被引量:4
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作者 于志强 周健义 +2 位作者 赵丽 周飞 李江 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期276-281,共6页
The development of a high performance wideband radio frequency (RF) transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band an... The development of a high performance wideband radio frequency (RF) transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex (TDD) mode and supports the multiple-input multipleoutput (MIMO) technique for the international mobile telecommunications (IMT)-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude (EVM) measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution (LTE)-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests. 展开更多
关键词 radio frequency (RF) transceiver orthogonal frequency division multiplexing (OFDM) IMT-advanced system phase noise low noise amplifier power amplifier LTE-advanced system
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Comparison of Growth and Development Traits among Crossbreds of Dorset and Local Sheep Varieties in Gansu Province 被引量:4
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作者 孙晓萍 刘建斌 +1 位作者 张万龙 冯瑞林 《Agricultural Science & Technology》 CAS 2016年第1期117-121,143,共6页
In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongoli... In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious. 展开更多
关键词 DORSET Mongolia sheep Small Tail Han sheep Tan sheep Crossbreeding combination Growth and development
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Detection for Transcriptional Activity of Alternaria Tenuissim Protein Elicitor in Yeast Two-hybrid System 被引量:3
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作者 刘延锋 邱德文 +1 位作者 曾洪梅 杨秀芬 《Agricultural Science & Technology》 CAS 2008年第1期64-66,共3页
The peaT1 gene fragment was amplified from pGEM-6p-l-peaT1 by PCR, and recovered target gene was cloned into pLexA vector. After digestion and sequencing, the bait vector pLexA-peaT1 was transformed into yeast strain ... The peaT1 gene fragment was amplified from pGEM-6p-l-peaT1 by PCR, and recovered target gene was cloned into pLexA vector. After digestion and sequencing, the bait vector pLexA-peaT1 was transformed into yeast strain EGY48 [p8op-lacZ] by PEG/LiAC, and the transcriptional activity of bait vector was detected. The results showed that recombinant bait plasmid pLexA-PEMG1 was constructed, for the two bands of recombinant bait plasmid in agarose gel eleetrophoresis were expected after digesting by restriction endonuclease EcoR I and Xho I. Therefore, the recombinant bait plasmid could be used in yeast two-hybrid system to screen a cDNA library. 展开更多
关键词 PeaT1 Yeast two-hybrid Transcriptional activity
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Observation on the Embryonic Development in Citrus after Cross Pollination 被引量:1
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作者 王家福 陈振光 林同香 《Developmental and Reproductive Biology》 1999年第2期57-63,共7页
Embryonic development was studied in six cross combinations ofCitrus sinensis x C. tangerina, C. sinensis x C. reticulata, C. sinensis x (C. tangerina + C.reticulata), C. sinensis x Poncirus trifoliate, C.reticulata x... Embryonic development was studied in six cross combinations ofCitrus sinensis x C. tangerina, C. sinensis x C. reticulata, C. sinensis x (C. tangerina + C.reticulata), C. sinensis x Poncirus trifoliate, C.reticulata x C grandis and C. grandis xPoncirus trifoliate. The results showed that on the 30th day after pollination thezygote remained a single cell. On the 40th day, the zygote began to divide. On the50th day, zygotic embryo became globular-shaped while nucellar embryos had notinvaded the embryo sac. On the 55th day, a few nucellar embryos began to invadethe embryo sac. On the 60th day, the zygotic embryo became heart-shaped, and atthe same time, a large number of nucellar embryos invaded the embryo sac. On the80th day after pollination, the zygotic embryo was surrounded by nucellar embryosand it was not easy to distinguish these embryos. The cross combination affected thedevelopments of zygotic embryos, ovules and fruits, which were mainly determined bythe cross parents. As compared with interspecies crossing, the zygotic division ofintergenus crossing began later, the zygotic embryos developed slowlier and theinvading time of nucellar embryos was also delayed. 展开更多
关键词 CITRUS zygotic embryo nucellar embryonic embryo development citruscrossing
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Effect of Microbial Inoculum Fertilizer on the Growth and Yield of Super Hybrid Rice 被引量:1
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作者 郭夏宇 艾治勇 《Agricultural Science & Technology》 CAS 2015年第11期2396-2398,共3页
The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The r... The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The results indicate that the treatment with traditional fertilizers and 4 500 g/hm2 HYT microbial inoculum fertilizer performed the best, where average number of tiller was 2.4 more than that of the control; the number of effective ear was 11.05% higher; yield increased by 10.3%. These have demonstrated that microbial inoculum fertilizer is of great value in pro- motion on super hybrid rice production. 展开更多
关键词 Microbial inoculum fertilizer Super hybrid rice Growth and development Yieid
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铝型材多彩镀色新工艺
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作者 张子中 《轻合金加工技术》 北大核心 1994年第12期41-41,共1页
关键词 铝型材 多彩镀色 中国有色金属工业技术开发交流中心 玻璃幕墙 铝扣板 铝合金家具
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Effects of Tiller-inhibitor on Growth and Yield Formation of Super Early Hybrid Rice Jinyou458 被引量:3
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作者 钱银飞 邱才飞 +5 位作者 邵彩虹 陈先茂 谢江 邓国强 彭春瑞 任天志 《Agricultural Science & Technology》 CAS 2011年第10期1444-1448,共5页
[Objective]The paper was to study the effect of tiller-inhibitor on the growth and yield formation of super early rice Jinyou 458.[Method] Two treatments including spraying tiller-inhibitor(TI) and spraying water(C... [Objective]The paper was to study the effect of tiller-inhibitor on the growth and yield formation of super early rice Jinyou 458.[Method] Two treatments including spraying tiller-inhibitor(TI) and spraying water(CK) at the SN-n stage were set in the test,the effect of tiller-inhibitor on yield and its components,leaf and plant morphology,field microclimate at booting stage and quality characteristics of rice population were studied.[Result] Spraying tiller-inhibitor could effectively reduce the occurrence of invalid and inefficient tillers,increase the proportion of high effective tillers(tiller with 4 or more leaves) in tiller composition at the maximal tiller stage.The panicle length,spikelets per panicle,spikelets density,number of secondary branches and the secondary spikelets,seed setting rate of rice plant sprayed with tiller-inhibitor were significantly higher than CK.Meanwhile,spraying tiller-inhibitor could increase plant height,biomass weight and leaf area index of rice population during middle and late stages of rice growing,improve the leaf temperature of top three leaves and the light transmittance of rice population at the booting stage,increase the leaf SPAD value,thus enhance photosynthetic capacity of rice plants.It also showed the characteristics of elongating the internode of rice plant and decreasing the stem thickness,etc.[Conclusion] The panicle-bearing rate of stems and tillers,effective panicles,spikelets per panicle,seed setting rate and 1 000-grain weight had coordinately increased after spraying tiller-inhibitor,thus increased the yield. 展开更多
关键词 Tiller-inhibitor Super early hybrid rice Jinyou 458 GROWTH YIELD
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Soft X ray Diagnosis on Seed Development and Observation on Seed Germination and Seedling Growth in Artificial Hybridization in Cunninghamia and Cryptomeria 被引量:1
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作者 李文钿 奇文清 +1 位作者 成小飞 胡适宜 《Acta Botanica Sinica》 CSCD 1999年第7期690-694,共5页
An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were ... An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were empty and a total of 628 looks plump. Soft X ray radiographs showed that, still and all, a majority of the “plump" seeds were embryoless (597, 95.6%) whereas some were partially developed (17,2.7%) and only a few were really full (14, 2.2%). 2. Germination test showed that all of the radiographed hybrid seeds with fully developed embryos were germinable whereas those with partially developed embryos were ungerminable. 3. Physiologically, the growth rate of hypocotyl, the date for shedding of seed coat and spreading of cotyledons, the elongation of epicotyl, and the branching of shoot of the 11 month old seedlings showed a tendency to fall behind those of the female parent; morphologically, the 11 month old hybrid seedlings with linear leaves appeared rather short, slender and weak, whereas the seedlings of the female parents with linear_lanceolate leaves appeared rather tall, stout and strong. 4. It is considered that the hybrid may be true and the crossability reveals a close phylogenetic affinity of Cunninghamia with Cryptomeria. 展开更多
关键词 Cunninghamia CRYPTOMERIA Artificial hybridization Soft X ray
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新疆博格达绒山羊与尼勒克本地山羊的杂交效果
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作者 柯丽白 依拉丁 +1 位作者 乃比江 吐尔逊 《新疆畜牧业》 1999年第3期17-18,共2页
新疆博格达绒山羊品种遗传性稳定,外貌特性一致,具有产绒量高,绒纤维细,耐粗饲粗放,适应性强等特点,为进一步探讨该品种与本地(尼勒克)山羊的杂交效果,加快我地区绒山羊的杂交利用,提高本地山羊产绒量,增加农牧民收入,提供了科学依据.于... 新疆博格达绒山羊品种遗传性稳定,外貌特性一致,具有产绒量高,绒纤维细,耐粗饲粗放,适应性强等特点,为进一步探讨该品种与本地(尼勒克)山羊的杂交效果,加快我地区绒山羊的杂交利用,提高本地山羊产绒量,增加农牧民收入,提供了科学依据.于1995年至1999年选点进行定点观测,目前已取得了良好的效果. 展开更多
关键词 新疆 绒山羊 本地山羊 遗传性 稳定发交
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Row-action SAGE algorithm for PET image reconstruction
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作者 周健 罗立民 朱宏擎 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期467-471,共5页
The one-block version of ordered subsets (OS) techniques was used to accelerate the convergent rate of the space-alternating generalized expectation-maximization (SAGE) algorithm. The new row-action SAGE (RA-SAGE) alg... The one-block version of ordered subsets (OS) techniques was used to accelerate the convergent rate of the space-alternating generalized expectation-maximization (SAGE) algorithm. The new row-action SAGE (RA-SAGE) algorithm processed projections in sequentially orthogonal order which reduced the dependency among the projections and speeds up the convergences. Additionally, the over-relaxation parameter in the direction defined by the RA-SAGE algorithm was also applied to obtain fast convergence to a globally maximum likelihood (ML) solution. In experiments, the RA-SAGE algorithm and the classical SAGE algorithm were compared in the application to positron emission tomography (PET) image reconstruction. Simulation results showed that RA-SAGE had better performance than SAGE in both convergence and image quality. 展开更多
关键词 Image quality Maximum likelihood estimation Positron emission tomography Signal to noise ratio
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Model of gas exchange dynamics for modified-atmosphere packages containing fresh produce
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作者 刘颖 李云飞 +1 位作者 王如竹 田平海 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期314-318,共5页
A model for modified-atmosphere packaging (MAP) systems containing fruits and vegetables was developed.The computer simulation was performed to predict the gas mass concentrations inside the packages and was success... A model for modified-atmosphere packaging (MAP) systems containing fruits and vegetables was developed.The computer simulation was performed to predict the gas mass concentrations inside the packages and was successfully verified by experiments with yellow peaches at 5,15 and 25 ℃ using two types of packaging films.A Michaelis-Menten type respiration model with noncompetitive inhibition mechanism due to CO2 was adopted while the respiration rates were measured with an improved permeable system method suitable for either steady or unsteady state.The applicability of the model in the design of MAP systems was demonstrated with a calculation to evaluate film specification and equilibrium concentrations of O2 and CO2 in the package containing yellow peaches. 展开更多
关键词 gas exchange dynamics modified-atmosphere package respiration rate yellow peach
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Adaptive channel estimation based on pilot signals and transform-domain processing in SISO/MIMO OFDM systems
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作者 宋铁成 尤肖虎 +1 位作者 沈连丰 宋晓晋 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期249-253,共5页
Based on the transform-domain characteristics of pilot signals,a band suppression filter is used as a transform-domain filter to restrain the interference of noise in channel estimation.The performance effect on chann... Based on the transform-domain characteristics of pilot signals,a band suppression filter is used as a transform-domain filter to restrain the interference of noise in channel estimation.The performance effect on channel estimation for an orthogonal frequency division multiplex (OFDM) system by different energy coefficients in the transform domain and the energy coefficient under the different signal-to-noise ratios (SNR) are also analyzed.A new energy coefficient expression is deduced.It is theoretically proven that dynamically selecting an energy coefficient can significantly improve the performance of channel estimation.Simulation results show that the proposed algorithm can achieve better performance close to the theoretic bounds of perfect channel estimation. The algorithm is adapted to single-input single-output (SISO) OFDM and multi-input multi-output (MIMO) OFDM systems. 展开更多
关键词 adaptive channel estimation orthogonal frequency division multiplex (OFDM) transmit diversity
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Influence range of emergency under special events based on CTM 被引量:6
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作者 陈茜 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期257-261,共5页
To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based ... To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events. 展开更多
关键词 traffic management special event EMERGENCY influence range cell transmission model (CTM)
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Current Situation and Development Countermeasures on Grassland Resource in Farming-pasturing Ecotone in West Jilin Province 被引量:6
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作者 尚红梅 《Agricultural Science & Technology》 CAS 2010年第7期94-98,共5页
Upon the current degradation situation of grassland in west Jilin Province,I analyzed the effects of natural factors and human activities on the degradation of grassland,and further purposefully put forward countermea... Upon the current degradation situation of grassland in west Jilin Province,I analyzed the effects of natural factors and human activities on the degradation of grassland,and further purposefully put forward countermeasures on the remediation and development of grassland.As a conclusion,scientifically utilizing and protecting the grassland resources could suppress grassland degradation,promoting the sustainable development of regional economy. 展开更多
关键词 West Jilin Province Farming-pasturing ecotone Grassland Resource Current situation Development Countermeasures
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Observation on Embryonic Development of Hybrid between Ryukin(♀) and Dragon-eye(♂) 被引量:1
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作者 丁庆忠 王芳 +2 位作者 齐遵利 张秀文 王锐 《Agricultural Science & Technology》 CAS 2012年第5期1105-1109,共5页
[Objective] This study aimed to observe the embryonic development of the F1 hybrid between Ryukin (♀) and Dragon-eye (♂). [Method] Embryonic development of the FI hybrid and parents between Ryukin (♀) and Dra... [Objective] This study aimed to observe the embryonic development of the F1 hybrid between Ryukin (♀) and Dragon-eye (♂). [Method] Embryonic development of the FI hybrid and parents between Ryukin (♀) and Dragon-eye (♂) was observed with XTL-2400 anatomical lens continuously. The organ characteristics and structures at each development stage were observed with OLYMPUS CKX41 microscopes, and photographed and recorded with a digital camera. [Result] At a water temperature of 25℃, the hatching time of the F1 hybrid is 51.3 h, the hatching time of Ryukin embryo is 52.4 h and that of Dragon-eye embryo is 56.3 h. [Conclusion] This study provides certain theoretical and practical basis for improving morphological characteristics of the existing Dragon-eye goldfish. 展开更多
关键词 HYBRIDIZATION Embryonic development Goldfis
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Exploration and Practice of Developing Hybrid Rice for Realizing Food Self-sufficiency in East Timor 被引量:1
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作者 方远祥 唐启源 +2 位作者 李迪秦 张建华 黄大辉 《Agricultural Science & Technology》 CAS 2011年第11期1617-1620,F0003,共5页
The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combina... The status, advantages and disadvantages of rice production in East Timor were investigated and analyzed, the results of comparison test and demonstrative cultivation through introducing 15 Chinese hybrid rice combinations into East Timor were summarized, the feasibility of developing hybrid rice in East Timor to realize food self-sufficiency were discussed and demonstrated, and the main corresponding technical strategies were proposed in this paper. 展开更多
关键词 East Timor Hybrid rice Demonstrative performance Developing strategies
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Accelerating SAGE algorithm in PET image reconstruction by rescaled block-iterative method 被引量:1
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作者 朱宏擎 舒华忠 +1 位作者 周健 罗立民 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期207-210,共4页
A new method to accelerate the convergent rate of the space-alternatinggeneralized expectation-maximization (SAGE) algorithm is proposed. The new rescaled block-iterativeSAGE (RBI-SAGE) algorithm combines the RBI algo... A new method to accelerate the convergent rate of the space-alternatinggeneralized expectation-maximization (SAGE) algorithm is proposed. The new rescaled block-iterativeSAGE (RBI-SAGE) algorithm combines the RBI algorithm with the SAGE algorithm for PET imagereconstruction. In the new approach, the projection data is partitioned into disjoint blocks; eachiteration step involves only one of these blocks. SAGE updates the parameters sequentially in eachblock. In experiments, the RBI-SAGE algorithm and classical SAGE algorithm are compared in theapplication on positron emission tomography (PET) image reconstruction. Simulation results show thatRBI-SAGE has better performance than SAGE in both convergence and image quality. 展开更多
关键词 positron emission tomography space-alternating generalizedexpectation-maximization image reconstruction rescaled block-iterative maximum likelihood
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