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971.
Polarisation of the particle spin can be an important problem for different plasmas. In this article, the contribution of the electron spin on the growth rate of the temperature anisotropy of electromagnetic instabilities has been investigated. Results show that polarisation of the electron spin will restrict the instability growth rate while instability can survive due to the spin-depolarised electrons even when the requested temperature anisotropy is vanished. Instability can reach the damping state exponentially due to the spin-polarised electrons while it can grow linearly due to the spin-depolarised (the semi-classical) electrons.  相似文献   
972.
We have presented non-linear analytical formula for fusion–fission cross-sections. This is achieved by analysing many fusion–fission experiments of the compound nuclei of atomic number range \(23 \le Z \le 146\) available in literature. Our parametrised formula can reproduce the fusion–fission cross-sections which agree well with the experiments. Our parametrisations depend on the charges and masses of the compound nuclei and fission fragments only. These results can be used as a guideline for estimating the fusion–fission cross-sections in those cases where measurements do not exist and also for studying new nuclei which are not yet explored.  相似文献   
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Wei Yuan  Ji Yan  Zhiyuan Tang  Li Ma 《Ionics》2012,18(3):329-335
A novel ultrasonic-assisted sol–gel method is proposed to prepare Li3V2(PO4)3/C cathode material. X-ray diffraction analyses show that both Li3V2(PO4)3/C(A) synthesized by the ultrasonic-assisted sol–gel method and Li3V2(PO4)3/C(B) synthesized by a traditional sol–gel method have monoclinic structure. Scanning electron microscopy images indicate that the Li3V2(PO4)3/C(A) composite has a more uniform morphology than that of the Li3V2(PO4)3/C(B) composite. In the voltage range of 3.0–4.3 V (vs. Li/Li+), the initial specific discharge capacities of the Li3V2(PO4)3/C(A) and Li3V2(PO4)3/C(B) samples are 129.8 and 125.9 mAh g−1 at 1C rate (1C = 133 mA g−1), respectively. Furthermore, at 2-C charge/10-C discharge rate, the specific discharge capacity of the Li3V2(PO4)3/C(A) composite retains 113.2 mAh g−1 after 50 cycles, but the Li3V2(PO4)3/C(B) composite only presents a capacity of 94.8 mAh g−1.  相似文献   
979.
Charge distribution characteristics were investigated for nanoparticles synthesized in a diffusion flame aerosol reactor. The nanoparticles considered were pristine TiO2 and Cu–TiO2, with Cu dopant concentrations ranging from 1 to 5 wt% with particle size from 25 to 60 nm. In situ measurements were conducted by integrating a tandem differential mobility analyzer (TDMA) experimental setup with the flame aerosol reactor. A charging model was used to identify the important parameters that govern the two charging mechanisms (diffusion and thermo-ionization) in the flame and their relative importance at different operating parameters. The results indicate that TiO2 and Cu–TiO2 nanoparticles carry single as well as double unit charges. The charged fraction depends on particle size as well as on dopant concentration. The charged fraction increased with increasing particle size and decreased with copper dopant concentration. Measured charged fractions were similar for both the polarities at different mobility diameters. Based on the flame operating parameters, the calculations indicate that diffusion charging is dominant in the flame, which is consistent with the experimental results.  相似文献   
980.
In order to solve the hierarchy problem, several extra-dimensional models have received considerable attention. We have considered a process where a Higgs boson is produced in association with a KK-graviton (G KK) at the LHC. At the leading order, this process occurs through the gluon fusion mechanism gghG KK via a quark loop. We compute the cross section and examine some features of this process in the ADD model. We find that the quark in the loop does not decouple in the large quark-mass limit just as in the case of ggh process. We compute the cross section of this process for the case of the RS model also. We examine the feasibility of this process being observed at the LHC.  相似文献   
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