Recent experimental developments in material sciences have generated hope that it will be possible to devise optical media where the difference in group velocity between the fundamental and third ...harmonic may be strongly suppressed. Under these circumstances both pulses would travel together over a long distance. This would lead to an enhancement of the generation process, and hence strong focusing and/or using ultra-short pulses might not be crucial. If the perfect phase matching condition is assumed, the only remaining mechanisms to decrease efficiency are self and cross phase modulation. Here we suggest that, instead of exactly matching wave vectors, we admit a small mismatch and show how it can be tailored to compensate for the cross phase modulation of the third harmonic by the fundamental during the generation process. This is very beneficial for the efficiency of third harmonic generation, even increasing it by a factor of two or more.
Climate in northeast Qinghai–Tibetan Plateau is characterised by the alternation of summer and winter monsoon circulation, which is generated by thermodynamic and kinetic effects of the immense ...plateau. The Plateau Monsoon system during the recent geological past has been investigated through a 44-m loess–paleosol section and a 17-m well to obtain the Plateau Monsoon climate changes during the last glacial–interglacial cycle.
Thermoluminescence (TL) and optically stimulated luminescence (OSL) methods, as well as field observations and stratigraphic correlation, are used to date the deposit. Magnetic susceptibility (MS), frequency-dependent magnetic susceptibility (FMS), and calcium carbonate content, which are regarded as proxy indicators of strength of the Plateau Summer Monsoon (PSM), are measured. Measurement of grain size distribution, which is regarded as a proxy index of strength of the Plateau Winter Monsoon (PWM), is also carried out. The results show that changes of the unique Plateau Monsoon system during the past 130 kyr are associated with the glacial and interglacial alternations in the Northern Hemisphere. The PSM was unusually strengthened during a period matching the marine oxygen isotope stage 5e (OIS 5e), but it was weak during the OIS 5a and OIS 5c, and was close to that of the OIS 3. The PWM was significantly depressed during OIS 3, and was as weak as that in the Holocene. The PWM and PSM circulations were not always coupled during the last glacial cycle. Changes of the Plateau Monsoon system did not always parallel the SE Asian monsoon, although linkage between them existed to some extent.
There are millennial-scale variations in the Plateau Monsoon system, but this is not further discussed in this paper.
In this study, polymorphisms in the goat
GnRHR gene exon 1 were detected by PCR-SSCP and DNA sequencing methods in 786 individuals from two different goat breeds. Two haplotypes (A and B), two ...observed genotypes (AA and AB), and two single nucleotide polymorphisms (SNPs) were detected, which resulted in five amino acid substitutions. The frequencies of haplotypes A and B in the two goat breeds were 0.78–0.83 and 0.17–0.22, respectively. The SNP locus was in Hardy–Weinberg disequilibrium in the two goat breeds (
P
<
0.05). Polymorphisms of the
GnRHR gene were shown to be associated with litter size in the two goat breeds. The SNPs in the goat
GnRHR gene had significant effects on litter size (
P
<
0.05). Therefore, these results suggest that the
GnRHR gene is a strong candidate gene that affects litter size in goat.
Polyarylene ether nitriles (PENs)/TiO2 nanocomposite has been successfully synthesized through the sol-gel process; the films were characterized by FTIR, XPS, SEM and TG. The dielectric properties of ...the films were also measured to find that the dielectric constant of nanocomposite films increases linearly with the TiO2 weight content and reaches 6.21 at a 20 wt.% TiO2 content. The nanocomposite films have favorable mechanical and thermal properties and are not sacrificing dielectric breakdown strength compared to that of pristine polymer.
Evolution characteristics of the microstructure and texture of severely deformed commercial purity Zr702 were studied. The mode of the severe deformation was either heavy cold rolling or equal ...channel angular (ECA) pressing. Equiaxed grains, present prior to the deformation, became elongated during deformation along the rolling direction or along the maximum shear direction for the case of cold rolling or that of ECA pressing, respectively. ECA pressing transformed the initial fiber texture to a quite different component, which was also the case for cold rolling. In both cases, the maximum intensity of texture increased with the amount of deformation. Complete recrystallization was realized upon subsequent heat treatment lasting 100 min. at 600 DGC, and the evolution characteristics of texture and microstructure were also similar for both modes of deformation. These similarities in the microstructure and texture were attributed to the particular route of ECA pressing employed in the present study, i.e., route A. It is therefore concluded that the deformation and annealing behaviors in this particular route of ECA pressing are essentially very close to those of cold rolling.
Using (106{+-}4)x10{sup 6} {psi}(3686) events accumulated with the BESIII detector at the BEPCII e{sup +}e{sup -} collider, we present the first measurement of decays of {chi}{sub c1} to vector meson ...pairs {phi}{phi}, {omega}{omega}, and {omega}{phi}. The branching fractions are measured to be (4.4{+-}0.3{+-}0.5)x10{sup -4}, (6.0{+-}0.3{+-}0.7)x10{sup -4}, and (2.2{+-}0.6{+-}0.2)x10{sup -5}, for {chi}{sub c1}{yields}{phi}{phi}, {omega}{omega}, and {omega}{phi}, respectively, which indicates that the hadron helicity selection rule is significantly violated in {chi}{sub cJ} decays. In addition, the measurement of {chi}{sub cJ}{yields}{omega}{phi} provides the first indication of the rate of doubly OZI-suppressed {chi}{sub cJ} decay. Finally, we present improved measurements for the branching fractions of {chi}{sub c0} and {chi}{sub c2} to vector meson pairs.
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