[ Objectives ] To study the reproductive behaviors and the effect of different pairing modes on the developmental status of incipient colonies'of Odontote- rmes fomosanus (Shiraki). [ Methods ] We observed the repr...[ Objectives ] To study the reproductive behaviors and the effect of different pairing modes on the developmental status of incipient colonies'of Odontote- rmes fomosanus (Shiraki). [ Methods ] We observed the reproductive behaviors of male alates, female Mates and mated alates respectively. Male and female Mates had 9 pairing modes and founded 170 incipient colonies under laboratory conditions. The effect of pairing mode on incipient colonies' developmental status was ana- lyzed. [ Results ] Two peaking hours of mating activity within the daily circadian rhythm of Mate activity appeared from 09:00 to 10:00, and from 21:00 to 22:00, respectively. Courtship behavior before mating consisted of touching with antennae, connecting into a ring (head-to-end), and licking. The reproductive behavior ( calling, pairing, tandem, mating and oviposition) of nestmate pairs was different to that of non-nestmate pairs. The pairing time of non-nestmate pairs was signifi- candy longer than that of alates paired with siblings (P 〈 0.05 ). The non-swarming alates could mate with swarming or non-swarming Mates and lay fertile eggs which hatched successfully. However, the survival rate of colonies founded by non-swarming alates was very low. The death rate of incipient colonies was in the range of 0.61% -0. 99% after three months, while the death rate of the colonies founded by swarming alates was in the range of 0.22% -0.58%. Females that had been experimentally prevented from mating could lay eggs, but the eggs did not hatch. [ Conclusion] There are two distinct hourly peaks of mating activity within each 24 hour period. Incipient colonies founded by outbreeding have the highest probability of survival.展开更多
For accurate Finite Element(FE)modeling for the structural dynamics of aeroengine casings,Parametric Modeling-based Model Updating Strategy(PM-MUS)is proposed based on efficient FE parametric modeling and model updati...For accurate Finite Element(FE)modeling for the structural dynamics of aeroengine casings,Parametric Modeling-based Model Updating Strategy(PM-MUS)is proposed based on efficient FE parametric modeling and model updating techniques regarding uncorrelated/correlated mode shapes.Casings structure is parametrically modeled by simplifying initial structural FE model and equivalently simulating mechanical characteristics.Uncorrelated modes between FE model and experiment are reasonably handled by adopting an objective function to recognize correct correlated modes pairs.The parametrized FE model is updated to effectively describe structural dynamic characteristics in respect of testing data.The model updating technology is firstly validated by the detailed FE model updating of one fixed–fixed beam structure in light of correlated/uncorrelated mode shapes and measured mode data.The PM-MUS is applied to the FE parametrized model updating of an aeroengine stator system(casings)which is constructed by the proposed parametric modeling approach.As revealed in this study,(A)the updated models by the proposed updating strategy and dynamic test data is accurate,and(B)the uncorrelated modes like close modes can be effectively handled and precisely identify the FE model mode associated the corresponding experimental mode,and(C)parametric modeling can enhance the dynamic modeling updating of complex structure in the accuracy of mode matching.The efforts of this study provide an efficient dynamic model updating strategy(PM-MUS)for aeroengine casings by parametric modeling and experimental test data regarding uncorrelated modes.展开更多
In structural simulation and design,an accurate computational model directly determines the effectiveness of performance evaluation.To establish a high-fidelity dynamic model of a complex assembled structure,a Hierarc...In structural simulation and design,an accurate computational model directly determines the effectiveness of performance evaluation.To establish a high-fidelity dynamic model of a complex assembled structure,a Hierarchical Model Updating Strategy(HMUS)is developed for Finite Element(FE)model updating with regard to uncorrelated modes.The principle of HMUS is first elaborated by integrating hierarchical modeling concept,model updating technology with proper uncorrelated mode treatment,and parametric modeling.In the developed strategy,the correct correlated mode pairs amongst the uncorrelated modes are identified by an error minimization procedure.The proposed updating technique is validated by the dynamic FE model updating of a simple fixed–fixed beam.The proposed HMUS is then applied to the FE model updating of an aeroengine stator system(casings)to demonstrate its effectiveness.Our studies reveal that(A)parametric modeling technique is able to build an efficient equivalent model by simplifying complex structure in geometry while ensuring the consistency of mechanical characteristics;(B)the developed model updating technique efficiently processes the uncorrelated modes and precisely identifies correct Correlated Mode Pairs(CMPs)between FE model and experiment;(C)the proposed HMUS is accurate and efficient in the FE model updating of complex assembled structures such as aeroengine casings with large-scale model,complex geometry,high-nonlinearity and numerous parameters;(D)it is appropriate to update a complex structural FE model parameterized.The efforts of this study provide an efficient updating strategy for the dynamic model updating of complex assembled structures with experimental test data,which is promising to promote the precision and feasibility of simulation-based design optimization and performance evaluation of complex structures.展开更多
The unique wave-manipulation capabilities of zero-index metamaterials(ZIMs)offer a new opportunity for realizing bound states in the continuum(BICs).However,the relationship between anomalous scattering and BICs remai...The unique wave-manipulation capabilities of zero-index metamaterials(ZIMs)offer a new opportunity for realizing bound states in the continuum(BICs).However,the relationship between anomalous scattering and BICs remains underexplored when parity–time(PT)symmetry is introduced.In this work,we demonstrate that a BIC splits into a pair of lasing modes carrying opposite topological charges by introducing PT symmetry through gain-loss cylinders embedded in ZIM layers.Theoretical analysis and numerical simulations reveal that lasing and unidirectional transparency phenomena result from the singularities and exceptional points of the scattering matrix.Moreover,exceptional points can be tuned via propagation phase modulation in the air gap,and their coalescence produces quasi-BICs with symmetric responses.This work provides a framework for manipulating BICs and topological lasing modes in non-Hermitian systems,offering new insights for designing non-Hermitian photonic devices.展开更多
Various bond modes of the M-C(C5 ring) exist in metallocene compounds of group 14 heavier elements,mostly due to an intricate interaction between the lone electron pairs at the M center and the 6 p-electrons of the ...Various bond modes of the M-C(C5 ring) exist in metallocene compounds of group 14 heavier elements,mostly due to an intricate interaction between the lone electron pairs at the M center and the 6 p-electrons of the C5 ring.The tin(Ⅱ) metallocene complexes LSn R(L = HC[CMe(N-2,6-iPr2C6H3)]2,R = cyclopentadienyl,C5H5(1); indenyl,C9H7(2); fluorenyl,C(13)H9(3)) stabilized by the β-diketiminato ligand were prepared and utilized in the study on their solid and solution state structures.X-ray single-crystal diffraction data revealed an η~1-mode of the Sn-C(C5 ring) bond in each 1~3.However,the room temperature ~1H NMR spectral studies disclosed such a fluxional bonding mode in solution.The 119 Sn NMR studies suggested a quadruple coordination nature of the Sn center in 1 while the triple coordination manner was for the Sn atom in both 2 and 3.Then the variable-temperature(25~–75 ℃) ~1H NMR spectral studies for each 1~3 were performed,which detected the relaxation state structures of 1~3 at lower temperature.All of these results indicate a stereochemical activity of the lone electron pairs at the tin(Ⅱ) atom that definitely has an electronic interaction with the 6 p-electrons of the C5 ring.The observed Sn-C(C5 ring) bond modes appear influenced by either the metallocene size or the compound state existed.展开更多
基金Sponsored by the Doctoral Program of Higher Education(20123204110001)the Natural Science Foundation of Jiangsu Province,China(BK2012816)+3 种基金the Funding Project of Nanjing Municipal Construction Bureauthe Management Office of Dr.Sun Yat-Sen's Mausoleum(200409)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Nanjing Forestry University Southern Modern Forestry Collabotative Innovation Center
文摘[ Objectives ] To study the reproductive behaviors and the effect of different pairing modes on the developmental status of incipient colonies'of Odontote- rmes fomosanus (Shiraki). [ Methods ] We observed the reproductive behaviors of male alates, female Mates and mated alates respectively. Male and female Mates had 9 pairing modes and founded 170 incipient colonies under laboratory conditions. The effect of pairing mode on incipient colonies' developmental status was ana- lyzed. [ Results ] Two peaking hours of mating activity within the daily circadian rhythm of Mate activity appeared from 09:00 to 10:00, and from 21:00 to 22:00, respectively. Courtship behavior before mating consisted of touching with antennae, connecting into a ring (head-to-end), and licking. The reproductive behavior ( calling, pairing, tandem, mating and oviposition) of nestmate pairs was different to that of non-nestmate pairs. The pairing time of non-nestmate pairs was signifi- candy longer than that of alates paired with siblings (P 〈 0.05 ). The non-swarming alates could mate with swarming or non-swarming Mates and lay fertile eggs which hatched successfully. However, the survival rate of colonies founded by non-swarming alates was very low. The death rate of incipient colonies was in the range of 0.61% -0. 99% after three months, while the death rate of the colonies founded by swarming alates was in the range of 0.22% -0.58%. Females that had been experimentally prevented from mating could lay eggs, but the eggs did not hatch. [ Conclusion] There are two distinct hourly peaks of mating activity within each 24 hour period. Incipient colonies founded by outbreeding have the highest probability of survival.
基金co-supported by National Natural Science Foundation of China(Nos.51975124 and 51675179)Shanghai International Cooperation Project of One Belt and One Road of China(No.20110741700)Research Startup Fund of Fudan University(No.FDU38341)。
文摘For accurate Finite Element(FE)modeling for the structural dynamics of aeroengine casings,Parametric Modeling-based Model Updating Strategy(PM-MUS)is proposed based on efficient FE parametric modeling and model updating techniques regarding uncorrelated/correlated mode shapes.Casings structure is parametrically modeled by simplifying initial structural FE model and equivalently simulating mechanical characteristics.Uncorrelated modes between FE model and experiment are reasonably handled by adopting an objective function to recognize correct correlated modes pairs.The parametrized FE model is updated to effectively describe structural dynamic characteristics in respect of testing data.The model updating technology is firstly validated by the detailed FE model updating of one fixed–fixed beam structure in light of correlated/uncorrelated mode shapes and measured mode data.The PM-MUS is applied to the FE parametrized model updating of an aeroengine stator system(casings)which is constructed by the proposed parametric modeling approach.As revealed in this study,(A)the updated models by the proposed updating strategy and dynamic test data is accurate,and(B)the uncorrelated modes like close modes can be effectively handled and precisely identify the FE model mode associated the corresponding experimental mode,and(C)parametric modeling can enhance the dynamic modeling updating of complex structure in the accuracy of mode matching.The efforts of this study provide an efficient dynamic model updating strategy(PM-MUS)for aeroengine casings by parametric modeling and experimental test data regarding uncorrelated modes.
基金co-supported by National Natural Science Foundation of China(No.51975124)Shanghai International Cooperation Project of One Belt and One Road of China(No.20110741700)Major Research Special Project of Aeroengine and Gas Turbine of China(No.J2019-IV-0016)。
文摘In structural simulation and design,an accurate computational model directly determines the effectiveness of performance evaluation.To establish a high-fidelity dynamic model of a complex assembled structure,a Hierarchical Model Updating Strategy(HMUS)is developed for Finite Element(FE)model updating with regard to uncorrelated modes.The principle of HMUS is first elaborated by integrating hierarchical modeling concept,model updating technology with proper uncorrelated mode treatment,and parametric modeling.In the developed strategy,the correct correlated mode pairs amongst the uncorrelated modes are identified by an error minimization procedure.The proposed updating technique is validated by the dynamic FE model updating of a simple fixed–fixed beam.The proposed HMUS is then applied to the FE model updating of an aeroengine stator system(casings)to demonstrate its effectiveness.Our studies reveal that(A)parametric modeling technique is able to build an efficient equivalent model by simplifying complex structure in geometry while ensuring the consistency of mechanical characteristics;(B)the developed model updating technique efficiently processes the uncorrelated modes and precisely identifies correct Correlated Mode Pairs(CMPs)between FE model and experiment;(C)the proposed HMUS is accurate and efficient in the FE model updating of complex assembled structures such as aeroengine casings with large-scale model,complex geometry,high-nonlinearity and numerous parameters;(D)it is appropriate to update a complex structural FE model parameterized.The efforts of this study provide an efficient updating strategy for the dynamic model updating of complex assembled structures with experimental test data,which is promising to promote the precision and feasibility of simulation-based design optimization and performance evaluation of complex structures.
基金supported by the National Natural Science Foundation of China(Grant Nos.12504361,12274313,and 62465005)the Natural Science Foundation of Guangxi(Grant No.2025GXNSFBA069179)the Guangxi Colleges and Universities Young and Middle-aged Teachers’Basic Scientific Research Ability Enhancement Project(Grant No.2025KY0093)。
文摘The unique wave-manipulation capabilities of zero-index metamaterials(ZIMs)offer a new opportunity for realizing bound states in the continuum(BICs).However,the relationship between anomalous scattering and BICs remains underexplored when parity–time(PT)symmetry is introduced.In this work,we demonstrate that a BIC splits into a pair of lasing modes carrying opposite topological charges by introducing PT symmetry through gain-loss cylinders embedded in ZIM layers.Theoretical analysis and numerical simulations reveal that lasing and unidirectional transparency phenomena result from the singularities and exceptional points of the scattering matrix.Moreover,exceptional points can be tuned via propagation phase modulation in the air gap,and their coalescence produces quasi-BICs with symmetric responses.This work provides a framework for manipulating BICs and topological lasing modes in non-Hermitian systems,offering new insights for designing non-Hermitian photonic devices.
基金supported by the National Natural Science Foundation of China(21473142 and 21673191)the National Innovative Research Team of China(IRT_14R31 and J1310024)
文摘Various bond modes of the M-C(C5 ring) exist in metallocene compounds of group 14 heavier elements,mostly due to an intricate interaction between the lone electron pairs at the M center and the 6 p-electrons of the C5 ring.The tin(Ⅱ) metallocene complexes LSn R(L = HC[CMe(N-2,6-iPr2C6H3)]2,R = cyclopentadienyl,C5H5(1); indenyl,C9H7(2); fluorenyl,C(13)H9(3)) stabilized by the β-diketiminato ligand were prepared and utilized in the study on their solid and solution state structures.X-ray single-crystal diffraction data revealed an η~1-mode of the Sn-C(C5 ring) bond in each 1~3.However,the room temperature ~1H NMR spectral studies disclosed such a fluxional bonding mode in solution.The 119 Sn NMR studies suggested a quadruple coordination nature of the Sn center in 1 while the triple coordination manner was for the Sn atom in both 2 and 3.Then the variable-temperature(25~–75 ℃) ~1H NMR spectral studies for each 1~3 were performed,which detected the relaxation state structures of 1~3 at lower temperature.All of these results indicate a stereochemical activity of the lone electron pairs at the tin(Ⅱ) atom that definitely has an electronic interaction with the 6 p-electrons of the C5 ring.The observed Sn-C(C5 ring) bond modes appear influenced by either the metallocene size or the compound state existed.