作者首次发现在枣铁倍蚜(Kaburagia ensigallis Tsai et Tang)的冬寄主藓类植物上普遍有该蚜的无翅孤雌侨蚜产生。冬季,该侨蚜一部分分化为具翅蚜性母,另一部分发育为侨好成蚜;次春,性母发育并羽化为具翅的春迁蚜过飞到倍树上成为结倍虫...作者首次发现在枣铁倍蚜(Kaburagia ensigallis Tsai et Tang)的冬寄主藓类植物上普遍有该蚜的无翅孤雌侨蚜产生。冬季,该侨蚜一部分分化为具翅蚜性母,另一部分发育为侨好成蚜;次春,性母发育并羽化为具翅的春迁蚜过飞到倍树上成为结倍虫源,同期该侨好成蚜开始在冬寄主藓上繁殖同型侨蚜后代,2月初至5月中、下旬已繁殖3个世代,直至11月均处于不断繁殖阶段。由此证明枣铁倍蚜是营复迁式全周期生活史型的昆虫。这一发现对于改善五倍子生产的经营管理、扩大该种倍林区域及增加五倍子产量具有重要的经济意义。展开更多
测定铁倍蚜属枣铁亚种7个种群共58个个体的mt DNA COI基因部分序列,分析其种群遗传结构和变异。结果表明,在测得的1 257 bp COI基因序列中有100个变异位点,58条序列共产生23个单倍型,其平均单倍型多样度为0.943±0.015,核苷酸多样度...测定铁倍蚜属枣铁亚种7个种群共58个个体的mt DNA COI基因部分序列,分析其种群遗传结构和变异。结果表明,在测得的1 257 bp COI基因序列中有100个变异位点,58条序列共产生23个单倍型,其平均单倍型多样度为0.943±0.015,核苷酸多样度为0.020±0.002,其中,4个单倍型为不同种群的共享单倍型(2个单倍型为主体单倍型),11个单倍型为独享单倍型,8个单倍型为同一种群不同个体共享。AMOVA分析显示,枣铁亚种种群间的遗传变异较高,且分化显著。TCS网络图和聚类关系综合分析显示,不同单倍型按地理分布形成较明显的簇群,其中,云南水富所有个体单独构成一个分支,与其余种群关系较远,该种群可能属于不同的种。展开更多
铁倍是指铁倍蚜寄生在盐肤木属红麸杨(Rhus punjabensis var. sinica)复叶主轴、叶翅和小叶上所形成的虫瘿的总称。铁倍蚜包括枣铁倍蚜、蛋铁蚜、铁倍花蚜等。铁倍是川东地区的主要倍种,不但产量高,而且质量好、单宁含量65～71％,是一...铁倍是指铁倍蚜寄生在盐肤木属红麸杨(Rhus punjabensis var. sinica)复叶主轴、叶翅和小叶上所形成的虫瘿的总称。铁倍蚜包括枣铁倍蚜、蛋铁蚜、铁倍花蚜等。铁倍是川东地区的主要倍种,不但产量高,而且质量好、单宁含量65～71％,是一种很有发展前途的倍子品种。但是目前铁倍生产都是在原产铁倍区域内发展,使一些无倍区而第二寄主和倍蚜虫丰富的地方无人问津,这样给铁倍资源造成了很大浪费,从而影响铁倍产量。为了解决这一问题,扩大铁倍产区,根据枣铁倍蚜等具有以无翅孤雌侨蚜在第二寄主宿存繁衍。展开更多
铁倍是指铁倍蚜寄生在盐肤木属(Rhus)上的红麸杨(Punjabensis Var Sinica Rehd at Wils),复叶主轴,叶翅和小叶上所形成的虫瘿的总称。铁倍包括枣、蛋铁倍和小铁枣、铁倍花等,产量高于角倍,立地条件较角倍立地条件粗放,是目前大有发展前...铁倍是指铁倍蚜寄生在盐肤木属(Rhus)上的红麸杨(Punjabensis Var Sinica Rehd at Wils),复叶主轴,叶翅和小叶上所形成的虫瘿的总称。铁倍包括枣、蛋铁倍和小铁枣、铁倍花等,产量高于角倍,立地条件较角倍立地条件粗放,是目前大有发展前途和推广的倍种。展开更多
A series of hydrogen storage Co-free AB3-type alloys were directly synthesized with vacuum mid-frequency melting method,within which Ni of La0.7Mg0.3Ni3 alloy was substituted by Fe,B and(FeB) alloy,respectively.Alloys...A series of hydrogen storage Co-free AB3-type alloys were directly synthesized with vacuum mid-frequency melting method,within which Ni of La0.7Mg0.3Ni3 alloy was substituted by Fe,B and(FeB) alloy,respectively.Alloys were characterized by XRD,EDS and SEM to investigate the effects of B and Fe substitution for Ni on material structure.The content of LaMg2Ni9 phase within La0.7Mg0.3Ni3 alloy reaches 37.9% and that of La0.7Mg0.3Ni2.9(FeB)0.1 alloys reduces to 23.58%.Among all samples,ground particles with different shapes correspond to different phases.The major substitution occurs in LaMg2Ni9 phase.Electrochemical tests indicate that substituted alloys have different electrochemical performance,which is affected by phase structures of alloy.The discharge capacity of La0.7Mg0.3Ni3 alloy reaches 337.3 mA·h/g,but La0.7Mg0.3Ni2.9(FeB)0.1 alloy gets better high rate discharge(HRD) performance at the discharge rate of 500 mA/g with a high HRD value of 73.19%.展开更多
In this paper, a novel split-winding doubly salient permanentmagnet (DSPM) motor is proposed and the theoretical and experimental studies on the magnetic field, static characteristics and control strategy of this moto...In this paper, a novel split-winding doubly salient permanentmagnet (DSPM) motor is proposed and the theoretical and experimental studies on the magnetic field, static characteristics and control strategy of this motor are carried out. The steady-state and dynamic models are presented and the output power equation is derived. The feasibility of extending the operation range of the DSPM motor by using split-windings is proved. The finite element method is used to analyze the magnetic field, in which the leakage flux outside the stator circumference is taken into account. Based on the operation principle and the static characteristics of the motor, the control strategy and scheme are developed and implemented in a microcomputer-based controller. According to the features of the 4-phase 8/6-pole DSPM motor, a half-bridge power converter without neutral is adopted to reduce the number of power devices and to eliminate the problem of voltage unbalance in the split capacitors. The experimental results on the prototype machine not only verify the theoretical analysis, but also show that the proposed DSPM motor drive possesses good steady-state and dynamic performances, offering high efficiency over wide power range, and that the split-winding topology can effectively extend the operation range of the DSPM motor.展开更多
文摘作者首次发现在枣铁倍蚜(Kaburagia ensigallis Tsai et Tang)的冬寄主藓类植物上普遍有该蚜的无翅孤雌侨蚜产生。冬季,该侨蚜一部分分化为具翅蚜性母,另一部分发育为侨好成蚜;次春,性母发育并羽化为具翅的春迁蚜过飞到倍树上成为结倍虫源,同期该侨好成蚜开始在冬寄主藓上繁殖同型侨蚜后代,2月初至5月中、下旬已繁殖3个世代,直至11月均处于不断繁殖阶段。由此证明枣铁倍蚜是营复迁式全周期生活史型的昆虫。这一发现对于改善五倍子生产的经营管理、扩大该种倍林区域及增加五倍子产量具有重要的经济意义。
文摘测定铁倍蚜属枣铁亚种7个种群共58个个体的mt DNA COI基因部分序列,分析其种群遗传结构和变异。结果表明,在测得的1 257 bp COI基因序列中有100个变异位点,58条序列共产生23个单倍型,其平均单倍型多样度为0.943±0.015,核苷酸多样度为0.020±0.002,其中,4个单倍型为不同种群的共享单倍型(2个单倍型为主体单倍型),11个单倍型为独享单倍型,8个单倍型为同一种群不同个体共享。AMOVA分析显示,枣铁亚种种群间的遗传变异较高,且分化显著。TCS网络图和聚类关系综合分析显示,不同单倍型按地理分布形成较明显的簇群,其中,云南水富所有个体单独构成一个分支,与其余种群关系较远,该种群可能属于不同的种。
文摘铁倍是指铁倍蚜寄生在盐肤木属红麸杨(Rhus punjabensis var. sinica)复叶主轴、叶翅和小叶上所形成的虫瘿的总称。铁倍蚜包括枣铁倍蚜、蛋铁蚜、铁倍花蚜等。铁倍是川东地区的主要倍种,不但产量高,而且质量好、单宁含量65～71％,是一种很有发展前途的倍子品种。但是目前铁倍生产都是在原产铁倍区域内发展,使一些无倍区而第二寄主和倍蚜虫丰富的地方无人问津,这样给铁倍资源造成了很大浪费,从而影响铁倍产量。为了解决这一问题,扩大铁倍产区,根据枣铁倍蚜等具有以无翅孤雌侨蚜在第二寄主宿存繁衍。
基金Project(2007AA11A104) supported by the High-tech Research and Development Program of ChinaProject(2009CB220100) supported by the National Basic Research Program of China
文摘A series of hydrogen storage Co-free AB3-type alloys were directly synthesized with vacuum mid-frequency melting method,within which Ni of La0.7Mg0.3Ni3 alloy was substituted by Fe,B and(FeB) alloy,respectively.Alloys were characterized by XRD,EDS and SEM to investigate the effects of B and Fe substitution for Ni on material structure.The content of LaMg2Ni9 phase within La0.7Mg0.3Ni3 alloy reaches 37.9% and that of La0.7Mg0.3Ni2.9(FeB)0.1 alloys reduces to 23.58%.Among all samples,ground particles with different shapes correspond to different phases.The major substitution occurs in LaMg2Ni9 phase.Electrochemical tests indicate that substituted alloys have different electrochemical performance,which is affected by phase structures of alloy.The discharge capacity of La0.7Mg0.3Ni3 alloy reaches 337.3 mA·h/g,but La0.7Mg0.3Ni2.9(FeB)0.1 alloy gets better high rate discharge(HRD) performance at the discharge rate of 500 mA/g with a high HRD value of 73.19%.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 59507001) .
文摘In this paper, a novel split-winding doubly salient permanentmagnet (DSPM) motor is proposed and the theoretical and experimental studies on the magnetic field, static characteristics and control strategy of this motor are carried out. The steady-state and dynamic models are presented and the output power equation is derived. The feasibility of extending the operation range of the DSPM motor by using split-windings is proved. The finite element method is used to analyze the magnetic field, in which the leakage flux outside the stator circumference is taken into account. Based on the operation principle and the static characteristics of the motor, the control strategy and scheme are developed and implemented in a microcomputer-based controller. According to the features of the 4-phase 8/6-pole DSPM motor, a half-bridge power converter without neutral is adopted to reduce the number of power devices and to eliminate the problem of voltage unbalance in the split capacitors. The experimental results on the prototype machine not only verify the theoretical analysis, but also show that the proposed DSPM motor drive possesses good steady-state and dynamic performances, offering high efficiency over wide power range, and that the split-winding topology can effectively extend the operation range of the DSPM motor.
