期刊文献+
共找到41篇文章
< 1 2 3 >
每页显示 20 50 100
山葡萄‘双优’组织培养生根期愈伤组织的转录组分析
1
作者 韦伟 单守明 +1 位作者 徐文娣 李光宗 《新疆农业科学》 CAS CSCD 北大核心 2023年第6期1451-1459,共9页
【目的】研究山葡萄生根的分子机理,为山葡萄生产繁殖中生根提供理论数据和参考依据。【方法】对山葡萄‘双优’进行组织培养至生根阶段,设置不同浓度IBA(0.1、0.3和0.5 mg/L)、NAA(0.1、0.3和0.5 mg/L)和蔗糖(15、25和35 g/L)处理,选... 【目的】研究山葡萄生根的分子机理,为山葡萄生产繁殖中生根提供理论数据和参考依据。【方法】对山葡萄‘双优’进行组织培养至生根阶段,设置不同浓度IBA(0.1、0.3和0.5 mg/L)、NAA(0.1、0.3和0.5 mg/L)和蔗糖(15、25和35 g/L)处理,选择根系数目差别较大的两组,对其基部生根的愈伤组织进行转录组测序分析。【结果】6个样本共获得的高质量序列共284.40 Gb,89.15%~90.3%的Clean Reads比对到参考基因组上,S6较S1中显著上调的差异表达基因537个,显著下调的差异表达基因277个,共814个差异表达基因。共805个差异表达基因注释到COG的21个分类中,主要包括未知功能、细胞内运输和信号转导机制等条目。差异表达基因主要富集于多糖结合、驱动蛋白复合体和生长素激活信号通路等条目。差异表达基因富集在苯丙烷生物合成、类黄酮生物合成和植物激素信号转导等通路。生长素途径中的11个差异表达基因均为上调表达,表达量差异较大的5个基因为IAA14、IAA22、IAA27、LAX3和A-ARR基因。转录组数据可信。【结论】通过对不同浓度的IBA、NAA和蔗糖诱导‘双优’葡萄组培苗生根的愈伤组织进行测序,获得了较为完整的转录组数据,并对其进行功能注释、富集分析和激素相关基因表达量分析。 展开更多
关键词 山葡萄 ‘双优’ 生根 愈伤组织 转录组测序
下载PDF
Optimization of dual electrolyte and characteristic of micro-arc oxidation coating fabricated on ZK60 Mg alloy 被引量:5
2
作者 芦笙 王泽鑫 +1 位作者 陈静 周小淞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期929-935,共7页
Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The ... Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The microstructural characteristics of coatings were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). Test of mass loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The effect of every element in the dual electrolyte system on voltage—time responses during MAO process and the coating characteristic were also analyzed and discussed systematically via single factor experiments. The results reveal that the main components of NaAlO 2 and Na 3 PO 4 as well as additives of NaOH, NaB4O7 and C6H5Na3O7 demonstrate different effects on MAO process and coating characteristics. By means of single factor experiments, an optimized dual electrolyte system was developed, containing 17.5 g/L NaAlO 2, 5.0 g/LNa3 PO4, 5.0 g/L NaOH, 3.0 g/L NaB4O7 and 4.2g/LC6H5Na3O7 . 展开更多
关键词 magnesium alloy micro-arc oxidation dual electrolyte OPTIMIZATION single factor experiment
下载PDF
Study on the Optimization of Two-dimensional Electrophoresis Technology System for Rapeseed Proteome 被引量:4
3
作者 王丽娟 任学敏 +4 位作者 杜艳慧 张其彬 罗水忠 姜绍通 郑志 《Agricultural Science & Technology》 CAS 2011年第5期625-629,共5页
[Objective] The research aimed to establish the two-dimensional electrophoresis(2-DE)technology which was suitable for the rapeseed proteome research.[Method] Xiangyou 17 was as the material.The sample preparation m... [Objective] The research aimed to establish the two-dimensional electrophoresis(2-DE)technology which was suitable for the rapeseed proteome research.[Method] Xiangyou 17 was as the material.The sample preparation method,gel concentration and loading amount,etc.in 2-DE technology were optimized.[Result] The best extraction method of total protein of rapeseed was TCA-acetone method,and the protein spots on 2-DE map were the most.When IPG strip(pH 3-10)and 12% gel were used,and the loading amount was 250 μg,the two-dimensional electrophoresis map with the clear background,good repeatability and high protein spot resolution was obtained.[Conclusion] The research laid the foundation for carrying out the rapeseed proteomics research. 展开更多
关键词 RAPESEED PROTEOME Two-dimensional electrophoresis System optimization
下载PDF
Genetic Improvement Progress and Productive Effect of Rapeseed in Henan Province 被引量:1
4
作者 朱家成 张书芬 +8 位作者 张书法 王建平 文雁成 何俊平 曹金华 蔡东芳 赵磊 王东国 隋天显 《Agricultural Science & Technology》 CAS 2017年第6期979-983,1006,共6页
The research progress and major achievements on genetic breeding, het- erosis utilization of rapeseed in Henan Province were summarized, with the aim to provide technical guidance for rapeseed genetic breeding in the ... The research progress and major achievements on genetic breeding, het- erosis utilization of rapeseed in Henan Province were summarized, with the aim to provide technical guidance for rapeseed genetic breeding in the future work. Faced with the problems of lack of special varieties, highly demand for healthy oil and high production cost in rapeseed production in recent years, the breeding goals of rapeseed have been adjusted from high yield, high quality and disease resistance to high oil, high oleic acid, adaptative to mechanization, late planting resistance. The breeding technologies mainly focused on the isolated microspore culture, molecular marker assisted selection, and the corresponding high efficiency technical systems were constructed. The innovative research on excellent germplasm resources were carried on, which created and established breeding populations and distinctive new germplasm resources with diverse variations such as high oil content, high oleic acid content and low linolenic acid, cold resistance, drought resistance, pod shatter resistance and different flower color variations. A series of rapeseed hybrids of dou- ble low varieties with strong heterosis and high oil contents were released and these hybrids significantly improved seed yield, quality and resistance. The average yield of rapeseed in Henan Province was 22.49% higher than the national average yield in 2003-2015. All of the achievements provided strong technical support for the upgrading of rapeseed varieties and increasing both production and income. 展开更多
关键词 RAPESEED Genetic improvement HETEROSIS Double low Germplasm in- novation
下载PDF
A Novel CMOSDual-Modulus Prescaler Based on New Optimized Structure and Dynamic Circuit Technique 被引量:8
5
作者 池保勇 石秉学 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第4期357-361,共5页
s:A divide- by- 12 8/ 12 9or6 4/ 6 5 dual- modulus prescaler based on new optimized structure and dynam ic circuit technique im plem ented in 0 .2 5 μm CMOS digital technology is described.New optimized structure re... s:A divide- by- 12 8/ 12 9or6 4/ 6 5 dual- modulus prescaler based on new optimized structure and dynam ic circuit technique im plem ented in 0 .2 5 μm CMOS digital technology is described.New optimized structure reduces the propagation delay and has higher operating speed.Based on this structure,an im proved D- flip- flop(DFF) using dynam ic circuit technique is proposed.A prototype is fabricated and the measured results show that this prescaler works well in gigahertz frequency range and consumes only35 m W(including three power- hungry output buffers) when the input frequency is2 .5 GHz and the power supply voltage is2 .5 V.Due to its excellent perform ance,the prescaler could be applied to many RF system s. 展开更多
关键词 dual- modulus prescaler D- flip- flop CMOS
下载PDF
The Breeding of Hybrid Rape Variety Youyan 924 with Strong Heterosis and High Oil
6
作者 侯国佐 侯燕 +2 位作者 何惠平 侯剑 王仙屏 《Agricultural Science & Technology》 CAS 2015年第8期1648-1652,1659,共6页
The rape project of "Development and Application of Cabbage Type Rape Hybrids with Strong Heterosis" which belongs to National 863 Program aimed to breed the rape variety whose rapeseed yield or oil yield increased ... The rape project of "Development and Application of Cabbage Type Rape Hybrids with Strong Heterosis" which belongs to National 863 Program aimed to breed the rape variety whose rapeseed yield or oil yield increased more than 10% compared with check (CK) variety, or oil yield increased more than 3 percentage points compared with CK. In the regional trial in the middle react,es of the Yangtze River for two years, the average rapeseed yield and oil yield of Youyan 924 which is a hybrid rape variety respectively reached 2 695.95 and 1 264.35 kg/hm2, which respectively increased by 5.22% and 13.4% compared with those of the other test- ing varieties in the same group, and respectively increased by 10.06% and 23.68% compared with those of Zhongyouza 2 which belongs to CK, thus reaching the standard of hybrid rape variety with strong heterosis; the average oil percentage of the variety in the two years was 46.63%,which increased by 3.44 percentage points compared with that of all the other testing varieties in the same group, and in- creased by 5.14 percentage points compared with that of Zhongyouza 2, and the oil percentage of it in the production testing reached 49.21%. Thus Youyan 924 is a variety with strong heterosis and high oil, moreover, its contents of erucic acid and glucosinolate are 0,25% and 20.27 μmol/g, respectively. From the data aggregation of national regional trial, it has the advantages of high oil yield, high yielding ability, reaching the standards of low erucic acid and low glucosinolate, strong lodging re- sistance, good disease resistance aqd moderate mature period. 展开更多
关键词 Youyan 924 Low erucic acid and low gtucosinolzte content Strongheterosis High oil Breeding of hybrid rape
下载PDF
Investigation on the Optimizing Range of CombustionChamber Configuration Parameters of DSCS 被引量:1
7
作者 李向荣 张国栋 魏熔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期147-153,共7页
Aim To obtain an optimizing range of the main configuration parameters of double swirls combustion system (DSCS) Methods To analyze the influence of DS combustion cham-ber configuration parameters on fuel spray and mi... Aim To obtain an optimizing range of the main configuration parameters of double swirls combustion system (DSCS) Methods To analyze the influence of DS combustion cham-ber configuration parameters on fuel spray and mixing by means of the fuel jet developmentperiphery charts obtained by the high speed photography with a modeling test device deve-loped by authors,and to examine it by the tests on a single cylinder diesel engine.Resultsand Conclusion The mixing process can be divided into four phases.The optimizing range of the ration of the inner chamber diameter to the cylinder bore,d2/D,is 0.4-0.7; and the outerchamber diameter,d1 the height of the circular ridge to the piston top face,h1,the radius of outer/inner chamber circle,R1,R2 ,the max depth of outer/inner chamber bowl,H1,H2,etc. are also important 展开更多
关键词 diesel engine double swirls combustion system configuration parameter optimizing range
下载PDF
Optimization of Field Arrangement of Doublecropping Glutinous Sorghum and Soybean Intercropping Pattern
8
作者 尹学伟 张晓春 +2 位作者 王培华 陈红 王红梅 《Agricultural Science & Technology》 CAS 2015年第6期1110-1114,共5页
In order to reduce successive cropping obstacles, optimize field arrange-ment of double-cropping of sorghum and soybean and improve yields, the research used Guojiaohong No.1 and Nandou No.12 as raw materials to explo... In order to reduce successive cropping obstacles, optimize field arrange-ment of double-cropping of sorghum and soybean and improve yields, the research used Guojiaohong No.1 and Nandou No.12 as raw materials to explore the effects of different field arrangements on yield and benefits of double-cropping. The results indicated that with the double-cropping, both of gross yield and output value were higher compared with single-cropping treatments; yield, thousand-grain weight, the weight of grain per ear, and ear length of the 1st-season glutinous sorghum de-creased as compartment width grew, and of regenerated sorghum and soybean changed from increasing to decreasing. Specifical y, with double-cropping system, gross yield of glutinous sorghum reached the highest at 8 352.9 kg/hm2 with com-partment width of 1.7 m and soybean yield the highest at 1 888.95 kg/hm2 with compartment width of 1.8 m. Additional y, gross output value and net incomes achieved the highest at 47 293.92 yuan/hm2 and 29 976.42 kg/hm2 for the two crops, with compartment width of 1.7 m, fol owed by the treatment with compart-ment width of 1.8 m. In general, the treatments with compartment widths of 1.7 and 1.8 m are optimal field arrangement. Additional y, output-to-input ratio was the high-est in the treatment with single-cropping glutinous sorghum and the least in the treatment with single-cropping soybeans. 展开更多
关键词 Double-cropping glutinous sorghum SOYBEAN Optimization of field ar-rangement
下载PDF
Outage Probability Minimization for Low-Altitude UAV-Enabled Full-Duplex Mobile Relaying Systems 被引量:6
9
作者 Meng Hua Yi Wang +3 位作者 Zhengming Zhang Chunguo Li Yongming Huang Luxi Yang 《China Communications》 SCIE CSCD 2018年第5期9-24,共16页
In this paper, a novel unmanned aerial vehicle(UAV)-enabled full duplex decode-and-forward(DF) technique is used in mobile relaying system. Compared with conventional static relaying, mobile relaying provides more deg... In this paper, a novel unmanned aerial vehicle(UAV)-enabled full duplex decode-and-forward(DF) technique is used in mobile relaying system. Compared with conventional static relaying, mobile relaying provides more degree of freedom for experiencing better channel conditions and further improving the system reliable performance. The source and relay transmit power as well as relay trajectory are jointly optimized for sum outage probability minimization in mobile relaying system. Due to the non-convex nature of the original problem, block coordinate decent optimization techniques are employed to decompose it into two sub-problems, which leads to an efficient iterative algorithm. Specifically, for the pre-determined relay trajectory, the optimal transmit power of source and relay are obtained by solving Karush-Kuhn-Tucker(KKT) conditions. For the given source/relay power allocation, the optimal UAV trajectory is obtained by solving dual problem. Based on the two steps, an iterative algorithm is proposed to jointly optimize source/relay power allocation and UAV trajectory alternately. Numerical results show the performance gain of our proposed scheme. 展开更多
关键词 unmanned aerial vehicle DECODE-AND-FORWARD full-duplex power allocation trajectory optimization
下载PDF
Heterosis and combining ability:a diallel cross of three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino 被引量:11
10
作者 邓岳文 刘晓 +1 位作者 张国范 吴富村 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1195-1199,共5页
We conducted a complete diallel cross among three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino to determine the heterosis and the combining ability of growth traits at the spat sta... We conducted a complete diallel cross among three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino to determine the heterosis and the combining ability of growth traits at the spat stage.The three populations were collected from Qingdao(Q) and Dalian(D) in China,and Miyagi(M) in Japan.We measured the shell length,shell width,and total weight.The magnitude of the general combining ability(GCA) variance was more pronounced than the specific combining ability(SCA) variance,which is evidenced by both the ratio of the genetic component in total variation and the GCA/SCA values.The component variances of GCA and SCA were significant for all three traits(P<0.05),indicating the importance of additive and non-additive genetic effects in determining the expression of these traits.The reciprocal maternal effects(RE) were also significant for these traits(P<0.05).Our results suggest that population D was the best general combiner in breeding programs to improve growth traits.The DM cross had the highest heterosis values for all three traits. 展开更多
关键词 Haliotis discus hannai Ino HETEROSIS combining ability
下载PDF
Synthesis and Surface Activity of Heterogemini Imidazolium Surfactants
11
作者 赵晓辉 叶志文 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第2期249-254,I0002,共7页
A series of heterogemini imidazolium surfactants with two-methylene spacer groups ([Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n) have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effect... A series of heterogemini imidazolium surfactants with two-methylene spacer groups ([Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n) have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effects of various reaction parameters, including stoichiometry, reaction temperature and time, were investigated. In addition, the surface activity study about heterogemini imidazolium surfactants was carried out and the influences of dissymmetric degree on the surface properties were also discussed. 展开更多
关键词 Heterogemini imidazolium surfactants SYNTHESIS Optimal conditions Surfaceactivity Dissymmetric degree
下载PDF
Two kinds of B-basis of the algebraic hyperbolic space 被引量:13
12
作者 李亚娟 汪国昭 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期750-759,共10页
In this paper, two new kinds of B-basis functions called algebraic hyperbolic (AH) Bézier basis and AH B-Spline basis are presented in the space Гk=span{ l,t ……f^k-3,sinht,cosht}, in which K is an arbitrary ... In this paper, two new kinds of B-basis functions called algebraic hyperbolic (AH) Bézier basis and AH B-Spline basis are presented in the space Гk=span{ l,t ……f^k-3,sinht,cosht}, in which K is an arbitrary integer larger than or equal to 3. They share most optimal properties as those of the Bézier basis and B-Spline basis respectively and can represent exactly some remarkable curves and surfaces such as the hyperbola, catenary, hyperbolic spiral and the hyperbolic paraboloid. The generation of tensor product surfaces of the AH B-Spline basis have two forms: AH B-Spline surface and AH T-Spline surface. 展开更多
关键词 Algebraic hyperbolic Bézier basis Algebraic hyperbolic B-Spline basis Algebraic hyperbolic Bézier curve Algebraic hyperbolic B-Spline curve
下载PDF
A two-phase tabu search approach to scheduling optimization in container terminals 被引量:1
13
作者 ZENG Qing-cheng YANG Zhong-zhen 《Journal of Marine Science and Application》 2007年第2期44-50,共7页
An optimization model for scheduling of quay cranes (QCs) and yard trailers was proposed to improve the overall efficiency of container terminals. To implement this model, a two-phase tabu search algorithm was designe... An optimization model for scheduling of quay cranes (QCs) and yard trailers was proposed to improve the overall efficiency of container terminals. To implement this model, a two-phase tabu search algorithm was designed. In the QCs scheduling phase of the algorithm, a search was performed to determine a good QC unloading operation order. For each QC unloading operation order generated during the QC's scheduling phase, another search was run to obtain a good yard trailer routing for the given QC's unloading order. Using this information, the time required for the operation was estimated, then the time of return to availability of the units was fed back to the QC scheduler. Numerical tests show that the two-phase Tabu Search algorithm searches the solution space efficiently, decreases the empty distance yard trailers must travel, decreases the number of trailers needed, and thereby reduces time and costs and improves the integration and reliability of container terminal operation systems. 展开更多
关键词 two-phase tabu search container terminal quay crane scheduling yard trailer routing
下载PDF
Model and algorithm of optimizing alternate traffic restriction scheme in urban traffic network 被引量:1
14
作者 徐光明 史峰 +1 位作者 刘冰 黄合来 《Journal of Central South University》 SCIE EI CAS 2014年第12期4742-4752,共11页
An optimization model and its solution algorithm for alternate traffic restriction(ATR) schemes were introduced in terms of both the restriction districts and the proportion of restricted automobiles. A bi-level progr... An optimization model and its solution algorithm for alternate traffic restriction(ATR) schemes were introduced in terms of both the restriction districts and the proportion of restricted automobiles. A bi-level programming model was proposed to model the ATR scheme optimization problem by aiming at consumer surplus maximization and overload flow minimization at the upper-level model. At the lower-level model, elastic demand, mode choice and multi-class user equilibrium assignment were synthetically optimized. A genetic algorithm involving prolonging codes was constructed, demonstrating high computing efficiency in that it dynamically includes newly-appearing overload links in the codes so as to reduce the subsequent searching range. Moreover,practical processing approaches were suggested, which may improve the operability of the model-based solutions. 展开更多
关键词 urban traffic congestion alternate traffic restriction equilibrium analysis bi-level programming model
下载PDF
Optimal Trajectory Planning of the Dual Arm Manipulator Using DAMM 被引量:1
15
作者 Chi-sung PARK Jae-hyun PARK Jang-myung LEE 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期127-131,共5页
This paper presents an optimal trajectory planning method of the dual arm manipulator using Dual Arm Manipulability Measure (DAMM). When the manipulator carries an object from a certain position to the destination, ... This paper presents an optimal trajectory planning method of the dual arm manipulator using Dual Arm Manipulability Measure (DAMM). When the manipulator carries an object from a certain position to the destination, various trajectory candidates could be conskied. TO select the optimal trajectacy from the several candidates, energy, time, and the length of the tmjecttay could be utilized. In order to quantify the carrying effidency of dual-arms, DAMM has been defined and applied for the decision of the optimal path. DAMM is defined as the interaction of the manipulability ellipsoids of the dualarras, while the manipulability measure irdicates the relationship between the joint velocity and the Cartesian velocity for each ann. The cast function for achieving the optimal path is defined as the Summation of the distance to the goal and inverse of this DAMM, which aims to generate the efficient motion to the goal. It is confirmed that the optimal path planning keeps higher manipulability through the short distance path by using computer simulation. To show the effectiveness of this cooperative control algorithm experimentally, a 5-DOF dual-ann robot with distributed controllers for synchronization control has been developed and used for the experiments. 展开更多
关键词 DAMM dual-arm optimal trajectory MANIPULABILITY distributed controller
下载PDF
Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam 被引量:8
16
作者 张小刚 宋玉普 吴智敏 《Transactions of Tianjin University》 EI CAS 2005年第1期59-65,共7页
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture t... By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice. 展开更多
关键词 roller-compacted concrete (RCC) arch dam induced crack double-K fracture parameters equivalent strength calculation model optimizing setting
下载PDF
Middle or low water pressure direct spiral double helix converging nozzle structure optimization and flow field analysis 被引量:1
17
作者 蒋林 Wu Ruolin +5 位作者 Zhao Hui Mei Peng Zhang Qiang Zhu Jiangyang Xiao Jun Lei Bin 《High Technology Letters》 EI CAS 2015年第3期261-268,共8页
In order to solve the problem of using new nozzle is proposed in fire rescue robot. middle or low water pressure to form fine water mist, a Existing water mist nozzles are basically used for high pressure and in large... In order to solve the problem of using new nozzle is proposed in fire rescue robot. middle or low water pressure to form fine water mist, a Existing water mist nozzles are basically used for high pressure and in large size, complex structure and poor low pressure atomization effect in comparison with requirement of snake-like fire rescue robots. On the basis of comprehensive typical spray noz- zles, a direct spiral double helix converging nozzle (DSDHCN) is proposed, which has the advanta- ges of small volume, light weight, simple structure, and convenient installation. To make the spray nozzle have good performance, and meet the requirements of more efficient fire extinguishing, a nu- merical study is carried out to analyze the internal and external full flow field of nozzle. A gas-liquid two-phase flow is applied to simulate the external full flow field of nozzle with VOF model in fluent software. The simulation results show the real situation of water flow out of the atomization nozzle and the water jet trajectory. Some simulations about middle or low water pressure direct spiral double he- lix converging optimized nozzle have been done in 30bar pressure. The simulation results show that the optimized nozzle structure not only makes the spray droplets have a good cone angle, but also have a sufficient axial velocity,which proves the structure rationality of the proposed optimized nozzle. 展开更多
关键词 direct spiral double helix converging nozzle (DSDHCN) internal and external flow field analysis structure optimization water mist
下载PDF
Primer/Probe Optimization of RTq-PCR for Identification of Double-stranded (ds) RNA in Rhizoctonia solani
18
作者 Mary S. Chey Ashlee M. Long +1 位作者 Seema Bharathan Narayanaswamy Bharathan 《Journal of Life Sciences》 2015年第11期535-540,共6页
Rhizoctonia solani is a soil-borne pathogenic fungus with several distinct isolates that have been classified based on their anastomosis groups (AG's). Many isolates of these fungi contain double-stranded viral RNA... Rhizoctonia solani is a soil-borne pathogenic fungus with several distinct isolates that have been classified based on their anastomosis groups (AG's). Many isolates of these fungi contain double-stranded viral RNA (dsRNA) that are cytoplasmic and viral in origin. Research in our laboratory has studied the epidemiology and molecular biology of viral RNA in R. solani, making it a useful biological model in the development of protocols for the rapid identification of biological agents. In the present study the dsRNA from the isolate EGR-4 which is characteristically large at 3.301 Kb was purified. Attempts to clone middle (M)-size dsRNA fragments from R, solani have been very difficult primarily due to artifacts that co-purify including large (L)-size dsRNA in the fungus. Various MgC12 concentrations were tested to optimize full length dsRNA PCR product. Magnesium is required for DNA polymerase, and EGR-4 requires a specific concentration; thus, several MgC1z concentrations were tested. The dsRNA was analyzed by gel electrophoresis. The gel-purified, nuclease-treated dsRNA was reverse transcribed into cDNA and ligated into the p-jet cloning vector and transformed using E. coli. All such clones were sequenced and forward and reverse primers were generated using BLAST sequence via Biosearch Technology. The plasmids were purified from transformed cultures and amplified using real-time PCR (RTqPCR) with the primers (reverse CCACCGGAAGAGGGAAATCC, forward AGCGCTGACCTTGCTATCGA ATC) and probe (5' Fam-AGTGCCGATCAGCCCTCCACCG-BHQ 1 3'). The ideal primer/probe concentration was determined through optimization by comparing the lowest threshold concentration (Ct) values using the plasmid cDNA as a template. 展开更多
关键词 Life science Rhizoctoniasolani double-stranded (ds) RNA cryptic mycoviruses phylogenetic analysis q-PCR.
下载PDF
Connecting parameters optimization on unsymmetrical twin-tower structure linked by sky-bridge 被引量:1
19
作者 孙黄胜 刘默涵 朱宏平 《Journal of Central South University》 SCIE EI CAS 2014年第6期2460-2468,共9页
Based on a simplified 3-DOF model of twin-tower structure linked by a sky-bridge,the frequency response functions,the displacement power spectral density(PSD)functions,and the time-averaged total vibration energy were... Based on a simplified 3-DOF model of twin-tower structure linked by a sky-bridge,the frequency response functions,the displacement power spectral density(PSD)functions,and the time-averaged total vibration energy were derived,by assuming the white noise as the earthquake excitation.The effects of connecting parameters,such as linking stiffness ratio and linking damping ratio,on the structural vibration responses were then studied,and the optimal connecting parameters were obtained to minimize the vibration energy of either the independent monomer tower or the integral structure.The influences of sky-bridge elevation position on the optimal connecting parameters were also discussed.Finally,the distribution characteristics of the top displacement PSD and the structural responses,excited by El Centro,Taft and artificial waves,were compared in both frequency and time domain.It is found that the connecting parameters at either end of connection interactively affect the responses of the towers.The optimal connecting parameters can greatly improve the damping connections on their seismic reduction effectiveness,but are unable to reduce the seismic responses of the towers to the best extent simultaneously.It is also indicated that the optimal connecting parameters derived from the simplified 3-DOF model are applicable for two multi-story structures linked by a sky-bridge with dampers.The seismic reduction effectiveness obtained varies from 0.3 to 1.0 with different sky-bridge mass ratio.The displacement responses of the example structures are reduced by approximately 22% with sky-bridge connections. 展开更多
关键词 twin-tower connected structure sky-bridge connecting parameter optimization seismic response
下载PDF
Model tests on uplift capacity of double-belled pile influenced by distance between bells
20
作者 SUN Tao CUI Xin-zhuang +5 位作者 SUN Yan-feng HAN Ruo-nan MA Rui-jin YANG Jun-jie WANG Yi-lin CHANG Yu-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1630-1640,共11页
To optimize the distance between the bells in pile design,this paper reports a series of small scale tests on the uplift capacity of double belled piles embedded in dry dense sand considering different bell space rati... To optimize the distance between the bells in pile design,this paper reports a series of small scale tests on the uplift capacity of double belled piles embedded in dry dense sand considering different bell space ratios.Finite element modelling is also performed to evaluate the range of soil failure around the piles during pile uplift displacement.Test results show that when bell space ratio is 6 or 8,the uplift capacity reaches the peak value.The upper bell bears more load than the lower one for the piles with bell space ratio less than 6,while the lower bell bears more load than the upper one for the piles with bell space ratio larger than 8. 展开更多
关键词 doubled-belled pile optimized distance uplift bearing capacity model test sand foundation
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部