A series of bowlic cyclotriveratrylenes(CTV) with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing micr...A series of bowlic cyclotriveratrylenes(CTV) with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy.Several CTV derivatives show thermotropic liquid crystalline properties.The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy groups.The parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number.When the length of alkoxyl chains was even longer,a monotonous decrease occured.Nevertheless,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.展开更多
We calculated the harmonic spectra generated from the asymmetric molecules of HD^+ and HeH^2+. It is found that HD+produces only odd harmonics, while HeH^2+produces both odd and even harmonics. Further analysis re...We calculated the harmonic spectra generated from the asymmetric molecules of HD^+ and HeH^2+. It is found that HD+produces only odd harmonics, while HeH^2+produces both odd and even harmonics. Further analysis reveals that for both HD^+ and HeH^2+, the nuclear dipole acceleration can generate even harmonics, but it is three orders of magnitude lower than that of the electron. Hence, the electronic dipole acceleration dominates the harmonic generation. For HD^+,the electronic dipole acceleration only contributes to the generation of odd harmonics, but for HeH^2+it contributes to the generation of both odd and even harmonics. Besides, one concept of the broken degree of system-symmetry is proposed to explain the different odd-even property between the harmonic spectra of HD^+ and HeH^2+.展开更多
A series of aromatic-aliphatic copolyamides containing different aliphatic diamine units was synthesized by low temperature solution polycondensation. The liquid crystalline critical concentration (c*) and liquid crys...A series of aromatic-aliphatic copolyamides containing different aliphatic diamine units was synthesized by low temperature solution polycondensation. The liquid crystalline critical concentration (c*) and liquid crystalline critical temperature (T*) of these copolyamides exhibited an odd-even zigzag effect with the odd-even variation of carbon atom number in the aliphatic diamines used.展开更多
The comparative study of charge effect on the size-dependence stabilities of gold clusters Aun^z (n = 2-12, z = 0/±1) in gas phase is performed at the M06-L/Lanl2dz level. The lowest-energy structures charged b...The comparative study of charge effect on the size-dependence stabilities of gold clusters Aun^z (n = 2-12, z = 0/±1) in gas phase is performed at the M06-L/Lanl2dz level. The lowest-energy structures charged by -1, 0 and +1 are optimized. The result shows that the geo- metries of the clusters with over 7 atoms tend to be cake-like. From the two- to three-dimensional geometries, the oscillatory behaviors are exhibited in the structural and electronic properties with the most pronounced in energy gap. The amplitude for the positive clusters is bigger than both the neutral and negative clusters. The neutral clusters with even number of even-coordinated atoms are more stable than the neighbors with odd number of even-coordinated atoms, as is completely reversed for the charged clusters. The oscillatory behaviors for the charged clusters are opposite to that for the neutral clusters, as is attributed to the electron-paired effect.展开更多
The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with ...The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNC calculations show that the large odd-even difference in moments of inertia mainly comes from the interference contributions j(μν) from particles in high j intruder orbitals μ and ν quite near the Fermi surface, which have no counterpart in the BCS formalism. The effective monopole and quadrupole pairing interaction strengths are determined to fit the experimental odd-even differences in binding energies and bandhead moments of inertia. The experimental results for the variation of moments of inertia with rotational frequency ω are reproduced well by the PNC calculation. The nearly identical experimental moments of inertia between 236 U(gsb) and 238 U(gsb) at low frequencies hω≤ 0.20 MeV are also reproduced quite well.展开更多
This paper discusses the properties of amplitude-squared squeezing of the generalized odd-even coherent states of anharmonic oscillator in finite-dimensional Hilbert space. It demonstrates that the generalized odd coh...This paper discusses the properties of amplitude-squared squeezing of the generalized odd-even coherent states of anharmonic oscillator in finite-dimensional Hilbert space. It demonstrates that the generalized odd coherent states do exhibit strong amplitude-squared squeezing effects in comparison with the generalized even coherent states.展开更多
In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically revi...In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically reviewed.In this context,general-ized odd-even mode theory is advanced to quantitatively and approximately describe the mutual coupling effect between a feed line and an antenna.As is mathematically deduced and demonstrated,the modal parity mismatch between the feed line and the antenna should ultimately dominate the unbalance phenomenon in antenna systems.Thus,an elegant,closed-form formula is derived to ap-proximately calculate the“unbalance degree”of a straight dipole off-center fed by a symmetric twin-wire line.Design approaches for the simplest,linear,1-D multimode resonant antennas are introduced.Moreover,the“falling tone excitation”law gauged based on prototype dipoles is revealed and used to develop a mode synthesis design approach for microstrip patch antennas(MPAs)and 2-D sectorial electric dipole antennas.Design examples with distinctive radiation performance are presented and discussed.Finally,possible development trends of multimode resonant antennas are prospected.展开更多
对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,...对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,重构效果差的缺点。所提出的方法将光伏阵列分为自由重构模块和固定重构模块,根据不同的阴影情况调整连接方式,确定最佳的连接关系,并与Arrow So Du ku,Zig-zag,OEC三种方法进行仿真实验对比,仿真结果表明,经过OOEC重构后的光伏阵列输出功率明显提高,光伏阵列的PU输出特性曲线更加趋向于单峰,并且从失配损耗,功率提升百分比,性能比,均衡指数上看来,OOEC有着更好的性能。展开更多
In our previous studies[Phys.Rev.C 97,044619(2018);Phys.Rev.C 103,044610(2021)],a universal odd-even staggering(OES)has been observed in extensive cross sections of isotopes not far from stability,measured for differe...In our previous studies[Phys.Rev.C 97,044619(2018);Phys.Rev.C 103,044610(2021)],a universal odd-even staggering(OES)has been observed in extensive cross sections of isotopes not far from stability,measured for different fragmentation and spallation reactions.Four OES relations have been proposed on the basis of this OES universality.However,it is still unclear whether this OES universality and OES relations are applicable to many isotopes near the drip-lines.Here,the OES in recent experimental cross sections of very neutron-rich nuclei approaching the drip-line(from ^(76)Ge,^(82)Se+^(9)Be)is quantitatively investigated,to further validate the OES universality and OES relations.The OES magnitudes in these experimental data approaching the neutron drip-line generally agree with those evaluated previously,mainly from experimental data near stability.New OES evaluations de-rived from these experimental data are also recommended for more exotic nuclei near the neutron drip-line,which extends the conclusions of our previous OES studies.In addition,the OES relation calculations are consistent with these experimental data of very neutron-rich nuclides according to their comparisons in this work.Finally,comparisons with additional experimental data(from ^(238)U+^(9)Be)also support that new OES evaluations and OES relation calculations can be applied for exotic nuclei near the neutron drip-line.展开更多
A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which...A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which can be considered as compelling evidence for pairing and blocking effect in super-deformed nudei. With increasing rotational frequency the odd-even differences become weaker and weaker due to the Coriolis anti-pairing effects. Particularly, the odd-even differences in the dynamic moments of inertia become obscure when hω≥2 MeV, and in certain cases there emerges nearly identical value of J(2) for some neighboring nudei. However, the odd-even differences in the kinematic moments of inertia still remain to certain extent at the highest frequencies.展开更多
We demonstrate here seven pure cyclic samples, which belongs to two series of oligoesters, cyclic oligo(trimethylene terephthalate)s (COTTs) and cyclic oligo(butylene terephthalate)s (COBTs), showing odd-even ...We demonstrate here seven pure cyclic samples, which belongs to two series of oligoesters, cyclic oligo(trimethylene terephthalate)s (COTTs) and cyclic oligo(butylene terephthalate)s (COBTs), showing odd-even effect of degree of oligomerization (repeating units number) on properties. The pentamer of COTT and trimer of COBT show much lower melting temperature, and the trimer of COTT and trimer of COBT show significant lower refractive index, which can be ascribed to the low packing density of cyclic oligoesters with odd number of degree of oligomerization. Our results reveal the discrete property change as a function of cyclic size of oligomers, which can be used to design materials with special properties.展开更多
The peptide assembly structures of polyglutamine (PolyQ) have been studied by using scanning tunneling microscopy (STM) with high spatial resolution in ambient conditions. 4,4'-Bipyridyl (4Bpy) was introduced i...The peptide assembly structures of polyglutamine (PolyQ) have been studied by using scanning tunneling microscopy (STM) with high spatial resolution in ambient conditions. 4,4'-Bipyridyl (4Bpy) was introduced into the PolyQ7 and PolyQ8 peptide assemblies for labeling the C-termini of the peptides. The fine structures of the 4Bpy-PolyQ7 and 4Bpy-PolyQ8 co-assemblies are observed, and the statistics of the apparent peptide strand length reveal different length distributions for PolyQ7 and PolyQs. One predominant apparent peptide strand length is ob- served for PolyQ7 reflecting one predominant peptide conformation in assembly structures, while three major ap- parent strand lengths can be identified with PolyQ8 reflecting three co-existing peptide conformations in peptide as- semblies. Such drastic difference in assembling characteristics can be considered as a reflection of asymmetric ad- sorption effect ofpeptides relating to odd-even residue numbers of PolyQ7 and PolyQ8,展开更多
基金Supported by the National Natural Science Foundation of China(No.20774077)the Natural Science Foundation of Fujian Province,China(No.E0510003, E0710025)the Project of Science and Technology of Xiamen City,China(No.3502Z20055013)
文摘A series of bowlic cyclotriveratrylenes(CTV) with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy.Several CTV derivatives show thermotropic liquid crystalline properties.The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy groups.The parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number.When the length of alkoxyl chains was even longer,a monotonous decrease occured.Nevertheless,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404153,11135002,11475076,and 11405077)the Fundamental Research Funds for the Central Universities of China(Grants Nos.lzujbky-2016-29,lzujbky-2016-31,and lzujbky-2016-209)
文摘We calculated the harmonic spectra generated from the asymmetric molecules of HD^+ and HeH^2+. It is found that HD+produces only odd harmonics, while HeH^2+produces both odd and even harmonics. Further analysis reveals that for both HD^+ and HeH^2+, the nuclear dipole acceleration can generate even harmonics, but it is three orders of magnitude lower than that of the electron. Hence, the electronic dipole acceleration dominates the harmonic generation. For HD^+,the electronic dipole acceleration only contributes to the generation of odd harmonics, but for HeH^2+it contributes to the generation of both odd and even harmonics. Besides, one concept of the broken degree of system-symmetry is proposed to explain the different odd-even property between the harmonic spectra of HD^+ and HeH^2+.
文摘A series of aromatic-aliphatic copolyamides containing different aliphatic diamine units was synthesized by low temperature solution polycondensation. The liquid crystalline critical concentration (c*) and liquid crystalline critical temperature (T*) of these copolyamides exhibited an odd-even zigzag effect with the odd-even variation of carbon atom number in the aliphatic diamines used.
基金supported by the National Natural Science Foundation of China(21063009)the Natural Science Foundation of Inner Mongolia(2012MS0218)+1 种基金the Natural Science Foundation of Inner Mongolia(No.2014BS0206)the Graduate Student Innovation Foundation of Inner Mongulia Normal University(CXJJS13045)
文摘The comparative study of charge effect on the size-dependence stabilities of gold clusters Aun^z (n = 2-12, z = 0/±1) in gas phase is performed at the M06-L/Lanl2dz level. The lowest-energy structures charged by -1, 0 and +1 are optimized. The result shows that the geo- metries of the clusters with over 7 atoms tend to be cake-like. From the two- to three-dimensional geometries, the oscillatory behaviors are exhibited in the structural and electronic properties with the most pronounced in energy gap. The amplitude for the positive clusters is bigger than both the neutral and negative clusters. The neutral clusters with even number of even-coordinated atoms are more stable than the neighbors with odd number of even-coordinated atoms, as is completely reversed for the charged clusters. The oscillatory behaviors for the charged clusters are opposite to that for the neutral clusters, as is attributed to the electron-paired effect.
文摘The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNC calculations show that the large odd-even difference in moments of inertia mainly comes from the interference contributions j(μν) from particles in high j intruder orbitals μ and ν quite near the Fermi surface, which have no counterpart in the BCS formalism. The effective monopole and quadrupole pairing interaction strengths are determined to fit the experimental odd-even differences in binding energies and bandhead moments of inertia. The experimental results for the variation of moments of inertia with rotational frequency ω are reproduced well by the PNC calculation. The nearly identical experimental moments of inertia between 236 U(gsb) and 238 U(gsb) at low frequencies hω≤ 0.20 MeV are also reproduced quite well.
文摘This paper discusses the properties of amplitude-squared squeezing of the generalized odd-even coherent states of anharmonic oscillator in finite-dimensional Hilbert space. It demonstrates that the generalized odd coherent states do exhibit strong amplitude-squared squeezing effects in comparison with the generalized even coherent states.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFE0205900)the Key Technologies R&D Program of Jiangsu(Prospective and Key Technologies for Industry)(Grant Nos.BE2022067 and BE2022067-2)。
文摘In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically reviewed.In this context,general-ized odd-even mode theory is advanced to quantitatively and approximately describe the mutual coupling effect between a feed line and an antenna.As is mathematically deduced and demonstrated,the modal parity mismatch between the feed line and the antenna should ultimately dominate the unbalance phenomenon in antenna systems.Thus,an elegant,closed-form formula is derived to ap-proximately calculate the“unbalance degree”of a straight dipole off-center fed by a symmetric twin-wire line.Design approaches for the simplest,linear,1-D multimode resonant antennas are introduced.Moreover,the“falling tone excitation”law gauged based on prototype dipoles is revealed and used to develop a mode synthesis design approach for microstrip patch antennas(MPAs)and 2-D sectorial electric dipole antennas.Design examples with distinctive radiation performance are presented and discussed.Finally,possible development trends of multimode resonant antennas are prospected.
文摘对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,重构效果差的缺点。所提出的方法将光伏阵列分为自由重构模块和固定重构模块,根据不同的阴影情况调整连接方式,确定最佳的连接关系,并与Arrow So Du ku,Zig-zag,OEC三种方法进行仿真实验对比,仿真结果表明,经过OOEC重构后的光伏阵列输出功率明显提高,光伏阵列的PU输出特性曲线更加趋向于单峰,并且从失配损耗,功率提升百分比,性能比,均衡指数上看来,OOEC有着更好的性能。
基金Supported by the National Natural Science Foundation of China(12005314)the SYSU 100 Top Talents Program。
文摘In our previous studies[Phys.Rev.C 97,044619(2018);Phys.Rev.C 103,044610(2021)],a universal odd-even staggering(OES)has been observed in extensive cross sections of isotopes not far from stability,measured for different fragmentation and spallation reactions.Four OES relations have been proposed on the basis of this OES universality.However,it is still unclear whether this OES universality and OES relations are applicable to many isotopes near the drip-lines.Here,the OES in recent experimental cross sections of very neutron-rich nuclei approaching the drip-line(from ^(76)Ge,^(82)Se+^(9)Be)is quantitatively investigated,to further validate the OES universality and OES relations.The OES magnitudes in these experimental data approaching the neutron drip-line generally agree with those evaluated previously,mainly from experimental data near stability.New OES evaluations de-rived from these experimental data are also recommended for more exotic nuclei near the neutron drip-line,which extends the conclusions of our previous OES studies.In addition,the OES relation calculations are consistent with these experimental data of very neutron-rich nuclides according to their comparisons in this work.Finally,comparisons with additional experimental data(from ^(238)U+^(9)Be)also support that new OES evaluations and OES relation calculations can be applied for exotic nuclei near the neutron drip-line.
文摘A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which can be considered as compelling evidence for pairing and blocking effect in super-deformed nudei. With increasing rotational frequency the odd-even differences become weaker and weaker due to the Coriolis anti-pairing effects. Particularly, the odd-even differences in the dynamic moments of inertia become obscure when hω≥2 MeV, and in certain cases there emerges nearly identical value of J(2) for some neighboring nudei. However, the odd-even differences in the kinematic moments of inertia still remain to certain extent at the highest frequencies.
基金financially supported by the National"973"Project(No.2011CB606004)the National Natural Science Foundation of China(Nos.21274099,21234005 and 21474067)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘We demonstrate here seven pure cyclic samples, which belongs to two series of oligoesters, cyclic oligo(trimethylene terephthalate)s (COTTs) and cyclic oligo(butylene terephthalate)s (COBTs), showing odd-even effect of degree of oligomerization (repeating units number) on properties. The pentamer of COTT and trimer of COBT show much lower melting temperature, and the trimer of COTT and trimer of COBT show significant lower refractive index, which can be ascribed to the low packing density of cyclic oligoesters with odd number of degree of oligomerization. Our results reveal the discrete property change as a function of cyclic size of oligomers, which can be used to design materials with special properties.
文摘The peptide assembly structures of polyglutamine (PolyQ) have been studied by using scanning tunneling microscopy (STM) with high spatial resolution in ambient conditions. 4,4'-Bipyridyl (4Bpy) was introduced into the PolyQ7 and PolyQ8 peptide assemblies for labeling the C-termini of the peptides. The fine structures of the 4Bpy-PolyQ7 and 4Bpy-PolyQ8 co-assemblies are observed, and the statistics of the apparent peptide strand length reveal different length distributions for PolyQ7 and PolyQs. One predominant apparent peptide strand length is ob- served for PolyQ7 reflecting one predominant peptide conformation in assembly structures, while three major ap- parent strand lengths can be identified with PolyQ8 reflecting three co-existing peptide conformations in peptide as- semblies. Such drastic difference in assembling characteristics can be considered as a reflection of asymmetric ad- sorption effect ofpeptides relating to odd-even residue numbers of PolyQ7 and PolyQ8,