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101.
采用碳酸钠和碳酸氢铵作为沉淀剂和络合剂,在水溶液中共沉淀Mn2+、Ni2+和Co2+以获得混合过渡金属元素的碳酸盐沉淀前驱体Mn0.675Ni0.1625Co0.1625CO3。并进一步合成高容量锂离子电池正极材料Li[Li0.2Co0.13Ni0.13Mn0.54]O2。考察了3种不同加料方式对共沉淀前驱体的结构、形貌和元素比例的影响,以及对最终产物的结构、形貌和电化学性能的影响。 相似文献
102.
Design and simulations for the detector based on DSSSD 总被引:1,自引:0,他引:1
The present paper describes the design and simulation results of a position-sensitive charged particle detector based on the Double Sided Silicon Strip Detector (DSSSD). Also, the characteristics of the DSSSD and its testing result were are discussed. With the application of the DSSSD, the position-sensitive charged particle detector can not only give particle flux and energy spectra information and identify different types of charged particles, but also measure the location and angle of incident particles. As the detector can make multi-parameter measurements of charged particles, it is widely used in space detection and exploration missions, such as charged particle detection related to earthquakes, space environment monitoring and solar activity inspection. 相似文献
103.
104.
197Au were irradiated with 47 MeV/u 12C ions. Iridium was produced via the multinucleon transfer reactions in bombardments of 197Au with 12C. and was separated radiochemically from Au and the mixture of the reaction products. The γ radioactivities of Ir isotopes were measured by using a HPGe detector. The production cross sections of Ir isotopes were determined from activities of Ir isotopes at the end of bombardment and the other relative data. It has been found that the cross sections for neutron-rich isotopes of iridium show an exponential dependence on the values of Qgg. Our experimental results also demonstrate lack of correlation between the cross sections and Qgg in the case of neutron-deficient isotopes of iridium. The fact can be explained from that neutron-rich isotopes of iridium were produced in the deep inelastic transfer reactions. 相似文献
105.
YUAN Shuang-Gui XU Yan-Bing DING Hua-Jie YANG Wei-Fan XIAO Yong-Hou NIU Yan-Ning 《中国物理C(英文版)》2009,33(Z1)
189W activities were produced via the 192Os(n, α) reaction using irradiation of isotopically enriched 192Os metallic powder of ~100 mg/cm2 with 14 MeV neutrons. The X-γ and γ-γ coincidence measurements were made so as to obtain γ rays from 189W decay and its coincidence relations. A new simple decay scheme of 189W including three γ rays of 210.2, 229.6 and 260.2 keV is proposed. Two new levels of 189Re at 470.4 and 489.8 keV are assigned. 相似文献
106.
107.
Yong Zheng Yan-Bing He Kun Qian Dongqing Liu Qingwen Lu Baohua Li Xindong Wang Jianling Li Feiyu Kang 《Ionics》2017,23(8):1967-1978
The lithium-ion batteries show extremely poor cycling performance at low temperature. The main degradation mechanism is not clear. To address the fading mechanism, the cycling degradation of commercial LiFePO4/mesocarbon microbead (MCMB) batteries under various charge rate (1/10C, 1/3C, 1/2C, and 1C) at ?10 °C is systematically investigated using nondestructive tests combining with post-mortem analysis. The low-temperature charging under high charge rates of 1/3C, 1/2C, and 1C results in severe lithium plating, which leads to extremely serious capacity loss. In contrast, no lithium plating occurred under low charge rate of 1/10C. The lithium plating on the anode surface leads to consumption of active lithium ions and electrolyte, which causes the capacity decay and increases ohmic resistance (R b) with cycling number under high charge rates. The lithium plating on the anode surface is partially reversible, which brings about the capacity recovery of batteries after 80 cycles at 25 °C. The above results are proved by the followed post-mortem measurements. The evolution of the surface morphologies of MCMB electrodes upon cycling shows that a layer composed of rod-like lithium is formed on the anode surface. 相似文献
108.
Zhong-Yu Ruan Yan-Bing Liang Shu-Lian Tan Ying-Xin Tang Wei-Quan Lin Prof. Jian-Zhong Wu Dr. Yong-Cong Ou 《化学:亚洲杂志》2021,16(8):931-936
Materials combining proton conductivity and magnetism have attracted great attention in recent years due to their intriguing application in sensors and fuel cells. Herein a two-dimensional metal-organic framework, [Cu(atz)2(H2O)2]⋅H2O ( 1 ) (Hatz=5-aminotetrazole), has been obtained in a green synthesis method. The single-crystal structure revealed that the atz− ligands as linkers coordinate with copper ions to sql networks, between which water molecules are immobilized through hydrogen bonds. The resulting complex 1 exhibits a high proton conductivity of 1.11×10−4 and 6.19×10−4 S cm−1 at room temperature and 333 K, respectively, under 98% RH with an activation energy of 0.56 eV. Upon dehydration, the proton conductivity of 1_dg drops by an order of magnitude. Furthermore, the magnetic behavior changes from long-range ferrimagnetic ordering of 1 to canted antiferromagnetic behaviour of 1_dg . 相似文献
109.
Measurement of stimulated Brillouin scattering (SBS) threshold based on waveform variation of SBS optical limiting 下载免费PDF全文
This paper proposes a method for measuring the stimulated
Brillouin scattering (SBS) threshold based on waveform variation of
SBS optical limiting. The output waveforms for different pump power
densities are numerically simulated, and validated in the Nd:YAG
seed-injected laser system. The results indicate that SBS does not
take place in the case of a low pump power density and thus the
output power scales up linearly with pump power. Once the pump power
density exceeds the SBS threshold, SBS takes place and thereby the
energies are transferred from pump to Stokes. As a result, a small
shoulder appears in the trailing edge of the output waveform, which
provides another method to determine the SBS threshold. 相似文献
110.
Hardy空间中的Bloch函数 总被引:1,自引:0,他引:1
本文利用单位圆盘内解析函数的Shimizu-Ahlfors特征函数分给出了Hardy空间中Bloch函数和BMOA的新特征。由此我们发现了B∩Hp(0<p<∞)与BMOA之间的本质差别。 相似文献