Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact...Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie.展开更多
A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were de...A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were designed.Using 4 L-type and 4 T-type HOM couplers,the longitudinal impedance and the transverse impedances were suppressed to below 3 kΩand 30 kΩ/m,respectivly.The HOM damping requirements of Hefei Advanced Light Facility(HALF)were satisfied.This paper conducted an in-depth study on the radio frequency(RF)design,multipacting optimization,and thermal analysis of these coaxial couplers.Simulation results indicated that under operating acceleration voltage,the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena.The cavity has the potential to reach a higher acceleration gradient.展开更多
Anhui musk deer [ Moschus ( moschiferus/berezovskii ) anhuiensis ] has been a taxonomic mystery since its discovery in early 80's.In this paper,with museum samples,we sequenced the complete cytochrome b ge...Anhui musk deer [ Moschus ( moschiferus/berezovskii ) anhuiensis ] has been a taxonomic mystery since its discovery in early 80's.In this paper,with museum samples,we sequenced the complete cytochrome b gene of five Anhui musk deer.When compared with other species in Genus Moschus ,Anhui musk deer showed a rather level of sequence divergence from all the other species in this genus.The phylogenetic trees constructed by multiple methods supported the same topology,in which the monophyly of Anhui musk deer was clearly demonstrated.Therefore,our molecular data suggest a full species status for Anhui musk deer ( Moschus anhuiensis ),rather than a subspecies of either M moschiferus or M berezovskii previously suggested by morphological studies.展开更多
Sequences from a region of the nuclear ribosomal 18S rDNA gene of approximately 1 912 base pairs (bp) were used to generate a molecular phylogeny for the Pentatomomorpha based on 53 species representing 21 putative ...Sequences from a region of the nuclear ribosomal 18S rDNA gene of approximately 1 912 base pairs (bp) were used to generate a molecular phylogeny for the Pentatomomorpha based on 53 species representing 21 putative families. Phylogenetic analyses using the most parsimony method (MP), maximum likelihood method (ML), and neighbor joining method (NJ) showed strong support that the Pentatomomorpha lineage is a monophyly and the superfamily Aradoidea is a sister group to the remainder of the Pentatomomorpha (Trichophora). The Trichophora could be divided into two clades : one clade consisted of the monophyletic superfamilies Pentatomoidea and Pyrrhocoroidea; the other was mainly the polyphyletic superfamilies Lygaeoidea, Coreoidea and Idiostoloidea. The superfamilies Lygaeoidea and Coreoidea were both polyphyletic. Within Lygaeoidea, Piesmatidae was sister to Berytidae. They formed a clade locating at the basal of the Trichophora and distantly related to the other two families Lygaeidae and Rhyparochromidae. This research suggested that 18S rDNA was a proper marker to reconstruct the phylogeny of Pentatomomorpha that was accordant to morphological studies and the research of Li et al (2005). The Pyrrhocoroidea was further divided from the Coreoidea (s./at ). It was suggested that the Piesmatidae might be assigned as a superfamily of Pentatomomorpha rather than a family in Lygaeoidea.展开更多
The phylogenetic relationships of genera in the subfamily Apaturinae were examined using mtDNA sequence data from 1,471 bp of cytochrome oxidase subunit Ⅰ (COI). The mitochondrial COI gene from a total of 16 specie...The phylogenetic relationships of genera in the subfamily Apaturinae were examined using mtDNA sequence data from 1,471 bp of cytochrome oxidase subunit Ⅰ (COI). The mitochondrial COI gene from a total of 16 species in 11 genera were sequenced to obtain mtDNA data, along with those of 4 species obtained from GenBank, to construct the MP and the NJ trees using Athyma jina, Penthema adelma, Polyura nepenthes, and Charaxes bernardus as outgroups. The transitions at the third codon positions of the COI data set were found saturated, but they were retained for analysis, because they contain the majority of the phylogenetic information. The impacts of equal weight assumptions for all characters in the parsimonious analysis were assessed by potential alternations in clades in response to different transition/transversion weighting schemes. The results indicated four distinct major groups in Apaturinae. Moreover, several well supported and stable clades were found in the Apaturinae. The study also identified undetermined taxon groups whose positions were weakly supported and were subject to changes under different weighting schemes. Within the Apaturinae, the clustering results are approximately identical to the classical morphological classification. The mtDNA data suggest the genus Mimathyma as a monophyletic group. Lelecella limenitoides and Dilipa fenestra have close relationship with very strong support in all phylogenetic trees. It also supports the taxonomic revision of removing several species from Apatura to other genera, namely Mimathyma schrenckii, M. chevana, M. nycteis, Chitoria subcaerulea, C. fasciola, C. pallas, and Helcyra subalba.展开更多
[Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homol...[Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homologous sequences between them and 11 relative species of Artemia from GenBank were compared;the molecular phylogenetic tree was constructed by Mega Microsoft using Artemiopsis stefanssoni as outgroup.[Result] Artemia persimilis was the primal group in genus Artemia;Artemia franciscana and Artemia monica were the evolved groups;Artemia urmiana,Artemia sinica and other Artemia species from China shared a close genetic relationship.[Conclusion] Based on the 16S rDNA sequence of them,the phylogenetic relationships of these bisexual Artemia species were A.persimilis→A.urmiana,A.sinica and A.tibetiana→A.tunisiana→A.monica→A.Franciscan.展开更多
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that...Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree.展开更多
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp...Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound.展开更多
Mitochondrial 12S and 16S ribosomal RNA genes sequences were sequenced using dye-labeled terminator on an ABI 377 automated sequencer in 11 individuals and 1 species' sequences were gained from GenBank,representin...Mitochondrial 12S and 16S ribosomal RNA genes sequences were sequenced using dye-labeled terminator on an ABI 377 automated sequencer in 11 individuals and 1 species' sequences were gained from GenBank,representing 6 genera of family Tetrigidae.The collated sequences were aligned using Clustal X version 1.81 and then,the sequence variability and heredity distances based on Kimura 2-parameter model were calculated using Mega 2.1.In obtained sequences (736 bp),the average A+T content is 73.9%,ranging from 71.2% to 77.5%;the overall G+C content is 26.1%,ranging from 22.5% to 28.8%.Based on alignment of the combined sequences,185 parsimony-informative sites were revealed in 755 available base pairs.Phylogenetic trees were reconstructed using NJ,MP and ML methods with Cylindraustralia kochii as outgroup.The results indicated that the monophyletic nature of Tetrix is questioned and suggest that T.tubercarina may be given tribal rank.Our results also show that Coptltettix huanjiangensis and C.gongshanensis are the same species,i.e.Coptltettix gongshanensis Zheng,and C.huanjiangensis is the synonyms of C.gongshanensis.展开更多
The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and...The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and Takhtajan's tribal classification in both analyses. Decaisneae and Sinofranchetieae are basal clades in the phylogenetic trees and external to all other taxa in the family. Lardizabaleae consisting of Boquila and Lardizabala are well supported in both trn L_F (100%) analysis and trn L_F and rbc L combined analysis (99%). Tribe Akebieae are strongly supported by a bootstrap value of 100% in both trn L_F analysis and trn L_F and rbc L combined analysis. However, the new genus Archakebia is nested within the genus Akebia in the trn L_F trees. In the combined trees, Archakebia is sister to Akebia with high bootstrap support. The inter_relationships among three closely related genera Parvatia , Holboellia and Stauntonia are still problematic. P. brunoniana ssp. elliptica is sister to H. latifolia in both analyses with low bootstrap support. H. parviflora is nested within the Stauntonia and sister to S. cavalerieana . Therefore, these three genera of tribe Akebieae may not be monophylytic and their generic boundary and delimitation need to be further studied, by exploring more molecular data, together with more morphological characters.展开更多
The design and fabrication of a RF MEMS switch is reported for the first time in China.The switching element consists of a thin metallic membrane,which has the metal-isolator-metal contact and a capacitive shunt switc...The design and fabrication of a RF MEMS switch is reported for the first time in China.The switching element consists of a thin metallic membrane,which has the metal-isolator-metal contact and a capacitive shunt switch as single-pole single-throw.When an electrostatic potential is applied to the membrane and the bottom electrode,the attractive electrostatic force pulls the metal membrane down onto the bottom dielectric.The switch characteristics,such as insertion loss and isolation,depend on the off and on-capacitance.The test results are as follows:the pulldown voltage is about 20V;the insertion loss is less than 0 69dB from DC to 20GHz in the up-state;the isolation is more than 13dB from 14 to 18GHz and 16dB from 18 to 20GHz in the down-state.展开更多
Pentatomomorpha is one of the most biodiverse infraorders among the true bugs(Hemiptera: Heteroptera). Phylogenetic relationships among the superfamilies within this infraorder have been uncertain, especially for t...Pentatomomorpha is one of the most biodiverse infraorders among the true bugs(Hemiptera: Heteroptera). Phylogenetic relationships among the superfamilies within this infraorder have been uncertain, especially for the Eutrichophora. The previous studies were based on morphological characters, or just mitochondrial or nuclear genes, or only partial 18 S rDNA and COI. In this study, we used maximum likelihood(ML) and Bayesian inference(BI) based on massive molecular datasets(18S rDNA, 28 S rDNA, Hox and mitochondrial genes totaling 21 loci and 12,538 characters) to infer a robust phylogeny for this terrestrial group. Results strongly support the monophyly of all superfamilies; the superfamily status of Aradoidea and the following relationships:(Aradoidea +(Pentatomoidea +(Coreoidea +(Lygaeoidea + Pyrrhocoroidea)))) in Pentatomomorpha, and(Coreoidea +(Lygaeoidea + Pyrrhocoroidea)) in Eutrichophora. Our results suggest that sampling greater numbers of genes is an effective tool for resolving phylogenetic problems.展开更多
To reduce the excessive vibration of a high-speed rotor system at the critical speed, a friction damper with a flexible support structure is introduced. The mechanism of vibration reduction and support characteristics...To reduce the excessive vibration of a high-speed rotor system at the critical speed, a friction damper with a flexible support structure is introduced. The mechanism of vibration reduction and support characteristics are analyzed and a friction damper is designed. The effect on an unbalanced response is studied. Results show that the stiffness factor and the friction-damping factor of the damper are related to the cone angle and the friction factor of the inner-ring when adopting a proper structure. By changing these parameters and the Z-directional stiffness of the outer-ring, the stiffness and the damping characteristic of the damper can be varied. Introducing a friction damper into the support can reduce the stiffness and increase the damping of the support, thus decreasing the critical speed to avoid the operating speed, suppress the resonant response of a rotor system, and attenuate vibration forces to the outside.展开更多
The progress of grey system models is reviewed, and the general grey numbers, the grey sequence op- erators and several most commonly used grey system models are introduced, such as the absolute degree of grey inciden...The progress of grey system models is reviewed, and the general grey numbers, the grey sequence op- erators and several most commonly used grey system models are introduced, such as the absolute degree of grey incidence model, the grey cluster model based on endpoint triangular whitenization functions, the grey cluster model based on center-point triangular whitenization functions, the grey prediction model of the model GM ( 1,1), and the weighted multi-attribute grey target decision model.展开更多
It*ss very important to identify the load on rotor bearing system. Based on load identification in time domain, a new method combined with transfer matrix method is applied in rubbing rotor bearing system to estimat...It*ss very important to identify the load on rotor bearing system. Based on load identification in time domain, a new method combined with transfer matrix method is applied in rubbing rotor bearing system to estimate the force on rubbing rotor for the first time. Avoiding calculating the modal parameters, the outside excitation force on multi point and the distribute of internal forces on rubbing rotor bearing system can be identified by this way at the same time. Finally, the simulation is made on partial lateral rubbing rotor bearing system. For the faulty of rotor/stator rub, the point where rubbing occurs and the change of impact forces can be detected by this method in order to improve the accuracy of rotor/stator rub faulty diagnosis.展开更多
The coupled dynamic characteristics of the conical electromagnetic bearing are presented and their definitions are given. On the basis of the analyses of the characteristics, the dynamic model of five degrees of freed...The coupled dynamic characteristics of the conical electromagnetic bearing are presented and their definitions are given. On the basis of the analyses of the characteristics, the dynamic model of five degrees of freedom (five-DOF) rotor-conical electromagnetic bearing system is made, and the influence of the coupled characteristics on the system optimal controller is analyzed.展开更多
Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s ...Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.展开更多
A semi-empirical interatomic potential formalism,the second-nearest-neighbor modified embedded-atom method(2NN MEAM),has been applied to obtaining interatomic potentials for the Co-W and Al-W binary system using previ...A semi-empirical interatomic potential formalism,the second-nearest-neighbor modified embedded-atom method(2NN MEAM),has been applied to obtaining interatomic potentials for the Co-W and Al-W binary system using previously developed MEAM potentials of Co,Al and W.The potential parameters were determined by fitting the experimental data on the enthalpy of formation,lattice parameter,melting point and elastic constants.The present potentials generally reproduce the fundamental physical properties of the Co-W and Al-W systems accurately.The lattice parameters,the enthalpy of formation,the thermal stability and the elastic constants match well with experiment and the first-principles results.The enthalpy of mixing and the enthalpy of formation and mixing of liquid are in good agreement with CALPHAD calculations.The potentials can be easily combined with already-developed MEAM potentials for binary cobalt systems and can be used to describe Co-Al-W-based multicomponent alloys,especially for interfacial properties.展开更多
Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heterop...Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heteroptera, and unsheathed testis occurs in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Psyloidea, Aphidoidea, Aleyrodoidea and Coccoidea. The testis also can be divide into three types by the shape of testicular follicles. The sphere-shaped type is found in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Aphidoidea and Aleyrodoidea, the tube-shaped type observed in Fulgoroidea, Psyloidea and Coccoidea, and the lamella-shaped type represented by Heteroptera. It is suggested the unsheathed testis may be the primitive type in Homoptera. Meiosis can be divided into 6 type at least, i.e. 1) Cicadoid type; 2) Fulgoroid type; 3) Psyloid type; 4) Aphidoid type; 5) Aleyrodoid type; and 6) Coccoid type. At least four groups exhibit a diffuse stage during meiosis prophase l, they are Psyloidea, Fulgoroidea, Coccoidea and Heteroptera. Sperm tail structures are similar to those reported from other insects with a typical 9+9+2 axoneme except that in Aleyrodoidea and Coccoidea whose sperm tail is degenerated.展开更多
文摘Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie.
基金supported by the Fundamental Research Funds for the Central Universities(WK2310000098).
文摘A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were designed.Using 4 L-type and 4 T-type HOM couplers,the longitudinal impedance and the transverse impedances were suppressed to below 3 kΩand 30 kΩ/m,respectivly.The HOM damping requirements of Hefei Advanced Light Facility(HALF)were satisfied.This paper conducted an in-depth study on the radio frequency(RF)design,multipacting optimization,and thermal analysis of these coaxial couplers.Simulation results indicated that under operating acceleration voltage,the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena.The cavity has the potential to reach a higher acceleration gradient.
基金This work received supportsfrom Natural Science Foundation of Yun nan Science Technology Committee granted to SuBingpartlys
文摘Anhui musk deer [ Moschus ( moschiferus/berezovskii ) anhuiensis ] has been a taxonomic mystery since its discovery in early 80's.In this paper,with museum samples,we sequenced the complete cytochrome b gene of five Anhui musk deer.When compared with other species in Genus Moschus ,Anhui musk deer showed a rather level of sequence divergence from all the other species in this genus.The phylogenetic trees constructed by multiple methods supported the same topology,in which the monophyly of Anhui musk deer was clearly demonstrated.Therefore,our molecular data suggest a full species status for Anhui musk deer ( Moschus anhuiensis ),rather than a subspecies of either M moschiferus or M berezovskii previously suggested by morphological studies.
文摘Sequences from a region of the nuclear ribosomal 18S rDNA gene of approximately 1 912 base pairs (bp) were used to generate a molecular phylogeny for the Pentatomomorpha based on 53 species representing 21 putative families. Phylogenetic analyses using the most parsimony method (MP), maximum likelihood method (ML), and neighbor joining method (NJ) showed strong support that the Pentatomomorpha lineage is a monophyly and the superfamily Aradoidea is a sister group to the remainder of the Pentatomomorpha (Trichophora). The Trichophora could be divided into two clades : one clade consisted of the monophyletic superfamilies Pentatomoidea and Pyrrhocoroidea; the other was mainly the polyphyletic superfamilies Lygaeoidea, Coreoidea and Idiostoloidea. The superfamilies Lygaeoidea and Coreoidea were both polyphyletic. Within Lygaeoidea, Piesmatidae was sister to Berytidae. They formed a clade locating at the basal of the Trichophora and distantly related to the other two families Lygaeidae and Rhyparochromidae. This research suggested that 18S rDNA was a proper marker to reconstruct the phylogeny of Pentatomomorpha that was accordant to morphological studies and the research of Li et al (2005). The Pyrrhocoroidea was further divided from the Coreoidea (s./at ). It was suggested that the Piesmatidae might be assigned as a superfamily of Pentatomomorpha rather than a family in Lygaeoidea.
基金This work was supported by National Natural Science Foundation of China (No. 30570247)the Natural Science Foundation of Shanxi Province (No. 2003-1087)
文摘The phylogenetic relationships of genera in the subfamily Apaturinae were examined using mtDNA sequence data from 1,471 bp of cytochrome oxidase subunit Ⅰ (COI). The mitochondrial COI gene from a total of 16 species in 11 genera were sequenced to obtain mtDNA data, along with those of 4 species obtained from GenBank, to construct the MP and the NJ trees using Athyma jina, Penthema adelma, Polyura nepenthes, and Charaxes bernardus as outgroups. The transitions at the third codon positions of the COI data set were found saturated, but they were retained for analysis, because they contain the majority of the phylogenetic information. The impacts of equal weight assumptions for all characters in the parsimonious analysis were assessed by potential alternations in clades in response to different transition/transversion weighting schemes. The results indicated four distinct major groups in Apaturinae. Moreover, several well supported and stable clades were found in the Apaturinae. The study also identified undetermined taxon groups whose positions were weakly supported and were subject to changes under different weighting schemes. Within the Apaturinae, the clustering results are approximately identical to the classical morphological classification. The mtDNA data suggest the genus Mimathyma as a monophyletic group. Lelecella limenitoides and Dilipa fenestra have close relationship with very strong support in all phylogenetic trees. It also supports the taxonomic revision of removing several species from Apatura to other genera, namely Mimathyma schrenckii, M. chevana, M. nycteis, Chitoria subcaerulea, C. fasciola, C. pallas, and Helcyra subalba.
基金Supported by National Natural Science Foundation of China(30770263)~~
文摘[Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homologous sequences between them and 11 relative species of Artemia from GenBank were compared;the molecular phylogenetic tree was constructed by Mega Microsoft using Artemiopsis stefanssoni as outgroup.[Result] Artemia persimilis was the primal group in genus Artemia;Artemia franciscana and Artemia monica were the evolved groups;Artemia urmiana,Artemia sinica and other Artemia species from China shared a close genetic relationship.[Conclusion] Based on the 16S rDNA sequence of them,the phylogenetic relationships of these bisexual Artemia species were A.persimilis→A.urmiana,A.sinica and A.tibetiana→A.tunisiana→A.monica→A.Franciscan.
基金Project(51071181)supported by the National Natural Science Foundation of ChinaProject(2013FJ4043)supported by the Natural Science Foundation of Hunan Province,China
文摘Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree.
基金Project(51071181)supported by the National Natural Science Foundation of ChinaProject(2013FJ4043)supported by the Natural Science Foundation of Hunan Province,China
文摘Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound.
文摘Mitochondrial 12S and 16S ribosomal RNA genes sequences were sequenced using dye-labeled terminator on an ABI 377 automated sequencer in 11 individuals and 1 species' sequences were gained from GenBank,representing 6 genera of family Tetrigidae.The collated sequences were aligned using Clustal X version 1.81 and then,the sequence variability and heredity distances based on Kimura 2-parameter model were calculated using Mega 2.1.In obtained sequences (736 bp),the average A+T content is 73.9%,ranging from 71.2% to 77.5%;the overall G+C content is 26.1%,ranging from 22.5% to 28.8%.Based on alignment of the combined sequences,185 parsimony-informative sites were revealed in 755 available base pairs.Phylogenetic trees were reconstructed using NJ,MP and ML methods with Cylindraustralia kochii as outgroup.The results indicated that the monophyletic nature of Tetrix is questioned and suggest that T.tubercarina may be given tribal rank.Our results also show that Coptltettix huanjiangensis and C.gongshanensis are the same species,i.e.Coptltettix gongshanensis Zheng,and C.huanjiangensis is the synonyms of C.gongshanensis.
文摘The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and Takhtajan's tribal classification in both analyses. Decaisneae and Sinofranchetieae are basal clades in the phylogenetic trees and external to all other taxa in the family. Lardizabaleae consisting of Boquila and Lardizabala are well supported in both trn L_F (100%) analysis and trn L_F and rbc L combined analysis (99%). Tribe Akebieae are strongly supported by a bootstrap value of 100% in both trn L_F analysis and trn L_F and rbc L combined analysis. However, the new genus Archakebia is nested within the genus Akebia in the trn L_F trees. In the combined trees, Archakebia is sister to Akebia with high bootstrap support. The inter_relationships among three closely related genera Parvatia , Holboellia and Stauntonia are still problematic. P. brunoniana ssp. elliptica is sister to H. latifolia in both analyses with low bootstrap support. H. parviflora is nested within the Stauntonia and sister to S. cavalerieana . Therefore, these three genera of tribe Akebieae may not be monophylytic and their generic boundary and delimitation need to be further studied, by exploring more molecular data, together with more morphological characters.
文摘The design and fabrication of a RF MEMS switch is reported for the first time in China.The switching element consists of a thin metallic membrane,which has the metal-isolator-metal contact and a capacitive shunt switch as single-pole single-throw.When an electrostatic potential is applied to the membrane and the bottom electrode,the attractive electrostatic force pulls the metal membrane down onto the bottom dielectric.The switch characteristics,such as insertion loss and isolation,depend on the off and on-capacitance.The test results are as follows:the pulldown voltage is about 20V;the insertion loss is less than 0 69dB from DC to 20GHz in the up-state;the isolation is more than 13dB from 14 to 18GHz and 16dB from 18 to 20GHz in the down-state.
基金supported by the National Natural Science Foundation of China (31372240, 31501840, 31440078)the Postdoctoral Science Foundation of China (134845)the Taiyuan Normal University Training Program of Innovation and Entrepreneurship for Undergraduates (CXCY1610)
文摘Pentatomomorpha is one of the most biodiverse infraorders among the true bugs(Hemiptera: Heteroptera). Phylogenetic relationships among the superfamilies within this infraorder have been uncertain, especially for the Eutrichophora. The previous studies were based on morphological characters, or just mitochondrial or nuclear genes, or only partial 18 S rDNA and COI. In this study, we used maximum likelihood(ML) and Bayesian inference(BI) based on massive molecular datasets(18S rDNA, 28 S rDNA, Hox and mitochondrial genes totaling 21 loci and 12,538 characters) to infer a robust phylogeny for this terrestrial group. Results strongly support the monophyly of all superfamilies; the superfamily status of Aradoidea and the following relationships:(Aradoidea +(Pentatomoidea +(Coreoidea +(Lygaeoidea + Pyrrhocoroidea)))) in Pentatomomorpha, and(Coreoidea +(Lygaeoidea + Pyrrhocoroidea)) in Eutrichophora. Our results suggest that sampling greater numbers of genes is an effective tool for resolving phylogenetic problems.
文摘To reduce the excessive vibration of a high-speed rotor system at the critical speed, a friction damper with a flexible support structure is introduced. The mechanism of vibration reduction and support characteristics are analyzed and a friction damper is designed. The effect on an unbalanced response is studied. Results show that the stiffness factor and the friction-damping factor of the damper are related to the cone angle and the friction factor of the inner-ring when adopting a proper structure. By changing these parameters and the Z-directional stiffness of the outer-ring, the stiffness and the damping characteristic of the damper can be varied. Introducing a friction damper into the support can reduce the stiffness and increase the damping of the support, thus decreasing the critical speed to avoid the operating speed, suppress the resonant response of a rotor system, and attenuate vibration forces to the outside.
基金Supported by the Joint Research Project of Both the National Natural Science Foundation of Chinaand the Royal Society(RS)of UK(71111130211)the National Natural Science Foundation of China(90924022,70971064,70901041,71171113)+7 种基金the Major Project of Social Science Foundation of China(10ZD&014)the Key Project of Social Science Foundation of China(08AJY024)the Key Project of Soft Science Foundation of China(2008GXS5D115)the Foundation of Doctoral Programs(200802870020,200902870032)the Foundation of Humanities and Social Sciences of Chinese National Ministry of Education(08JA630039)the Science Foundation ofthe Excellent and Creative Group of Science and Technology in Jiangsu Province(Y0553-091)the Foundation of Key Research Base of Philosophy and Social Science in Colleges and Universities of Jiangsu Province(2010JDXM015)the Foundation of Outstanding Teaching Group of China(10td128)~~
文摘The progress of grey system models is reviewed, and the general grey numbers, the grey sequence op- erators and several most commonly used grey system models are introduced, such as the absolute degree of grey incidence model, the grey cluster model based on endpoint triangular whitenization functions, the grey cluster model based on center-point triangular whitenization functions, the grey prediction model of the model GM ( 1,1), and the weighted multi-attribute grey target decision model.
文摘It*ss very important to identify the load on rotor bearing system. Based on load identification in time domain, a new method combined with transfer matrix method is applied in rubbing rotor bearing system to estimate the force on rubbing rotor for the first time. Avoiding calculating the modal parameters, the outside excitation force on multi point and the distribute of internal forces on rubbing rotor bearing system can be identified by this way at the same time. Finally, the simulation is made on partial lateral rubbing rotor bearing system. For the faulty of rotor/stator rub, the point where rubbing occurs and the change of impact forces can be detected by this method in order to improve the accuracy of rotor/stator rub faulty diagnosis.
文摘The coupled dynamic characteristics of the conical electromagnetic bearing are presented and their definitions are given. On the basis of the analyses of the characteristics, the dynamic model of five degrees of freedom (five-DOF) rotor-conical electromagnetic bearing system is made, and the influence of the coupled characteristics on the system optimal controller is analyzed.
文摘Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.
基金Project(51274167)supported by the National Natural Science Foundation of ChinaProject(LQ14E010002)supported by the Zhejiang Provincial Natural Science Foundation of ChinaProject(2E24692)supported by the KIST Institutional Programs,Korea
文摘A semi-empirical interatomic potential formalism,the second-nearest-neighbor modified embedded-atom method(2NN MEAM),has been applied to obtaining interatomic potentials for the Co-W and Al-W binary system using previously developed MEAM potentials of Co,Al and W.The potential parameters were determined by fitting the experimental data on the enthalpy of formation,lattice parameter,melting point and elastic constants.The present potentials generally reproduce the fundamental physical properties of the Co-W and Al-W systems accurately.The lattice parameters,the enthalpy of formation,the thermal stability and the elastic constants match well with experiment and the first-principles results.The enthalpy of mixing and the enthalpy of formation and mixing of liquid are in good agreement with CALPHAD calculations.The potentials can be easily combined with already-developed MEAM potentials for binary cobalt systems and can be used to describe Co-Al-W-based multicomponent alloys,especially for interfacial properties.
文摘Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heteroptera, and unsheathed testis occurs in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Psyloidea, Aphidoidea, Aleyrodoidea and Coccoidea. The testis also can be divide into three types by the shape of testicular follicles. The sphere-shaped type is found in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Aphidoidea and Aleyrodoidea, the tube-shaped type observed in Fulgoroidea, Psyloidea and Coccoidea, and the lamella-shaped type represented by Heteroptera. It is suggested the unsheathed testis may be the primitive type in Homoptera. Meiosis can be divided into 6 type at least, i.e. 1) Cicadoid type; 2) Fulgoroid type; 3) Psyloid type; 4) Aphidoid type; 5) Aleyrodoid type; and 6) Coccoid type. At least four groups exhibit a diffuse stage during meiosis prophase l, they are Psyloidea, Fulgoroidea, Coccoidea and Heteroptera. Sperm tail structures are similar to those reported from other insects with a typical 9+9+2 axoneme except that in Aleyrodoidea and Coccoidea whose sperm tail is degenerated.