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1.
Li J  Zhao GH  Li XY  Chen F  Chen JB  Zou FC  Yang JF  Lin RQ  Weng YB  Zhu XQ 《Electrophoresis》2011,32(12):1473-1479
In the present study, a inter-retrotransposon-amplified polymorphism (IRAP) technique, based on retrotransposons, was used to examine genetic variability among Schistosoma japonicum isolates from different provinces in mainland China. Of the 15 primers screened, 5 produced highly reproducible IRAP patterns. Using these primers, 54 discernible DNA fragments were generated with 40 (74.07%) being polymorphic, indicating considerable genetic variation among the examined S. japonicum isolates. The primer LTR-11 was found to be able to differentiate male and female parasites, producing one constant specific band for female S. japonicum isolates. The percentages of polymorphic bands (PPB) among all parasites, among isolates from mountainous provinces and among those from the lake/marshland areas were 74.07, 48.15, and 66.67%, respectively. UPGMA analysis revealed that the IRAP profiles could group S. japonicum isolates in mainland China into two clades (mountainous and lake/marshland types), and samples from the same geographical origins clustered together. These results demonstrated that the IRAP technique is suitable for studying genetic diversity and population structures, and also provides an effective technique for studying sex differentiation of S. japonicum.  相似文献   
2.
通过融合蒸发反应144Nd(19F,5n)布居了双奇核158Tm的高自旋态. 扩展了原来已知的带结构, 并建立了一条新转动带. 通过与相邻核的比较, 讨论158Tm核中两条四准粒子带的内禀组态, 并分别指定为πh11/2\otimes νh9/2(α=+1/2)\otimes (νi13/2)2和πh11/2\otimes νh9/2(α=-1/2)\otimes (νi13/2)2 组态. 建立在πh11/2\otimes νi13/2组态上的转动带被观测到呈现持续旋称反转现象, 而前述的两条高自旋区的 四准粒子转动带也呈旋称反转. 对这两种类型的旋称反转现象的可能机制进行了简单而定性的讨论.  相似文献   
3.
Lifetimes of high spin states in 129Cs axe measured using the Doppler shift attenuation method. The high spin states of 129 Cs axe populated following the fusion evaporation reaction 124 Sn(UB, 6n)129 Cs at a beam energy of 65 MeV. The reduced transition probabilities B(E2) and the transition quadrupole moments Qt in the negativeand positive-paxity bands are deduced. The experimental results indicate that the Qt values of the negative parity band are smaller than those of the positive parity bands, probably due to different γ-deformation driving effects of different proton orbitals. The Qt values exhibit a considerable increase near the band crossing region in these bands. This behavior demonstrates that nuclear shape changing results from the neutron or proton alignments. The signature splitting of the πh11/2 and πg7/2 bands shows the opposite changing trend after backbending due to the h11~2 neutron and h11/2 proton alignments, respectively.  相似文献   
4.
对"大学化学"课程的考核方法进行了改革。引入过程考核,降低期末考试在总成绩中的权重,在教学过程中增加理论联系实际的课外作业,以巩固基础理论知识的学习,并锻炼学生分析问题、解决问题的能力,作为考核指标记入总成绩。鼓励学生全程学习,避免突击应试。问卷调查结果表明大部分学生认同该考核方法。  相似文献   
5.
采用喷雾干燥法合成了富锂层状氧化物正极材料0.6Li[Li_(1/3)Mn_(2/3)]O2·0.4LiNi_(5/12)Mn_(5/12)Co_(1/6)O_2(简称LNMCO),并使用Zr(CH3COO)4进行ZrO_2的包覆改性。TEM测试结果显示纳米级的ZrO_2颗粒附着在LNMCO的表面。包覆质量分数为1.5%的ZrO_2包覆样品的首圈库伦效率和放电比容量有着显著提升,在室温下其首圈库伦效率和放电比容量(电流密度:20 m A·g-1,电压:2.0~4.8 V)分别为87.2%,279.3 m Ah·g-1,而原样则为75.1%,224.1 m Ah·g-1,循环100圈之后,1.5%ZrO_2包覆样品的放电比容量为248.3 m Ah·g-1,容量保持率为88.9%,高于原样的195.9 m Ah·g-1和87.4%。  相似文献   
6.
采用喷雾干燥法合成了富锂层状氧化物正极材料0.6Li[Li1/3Mn2/3]O2·0.4LiNi5/12Mn5/12Co1/6O2(简称LNMCO),并使用Zr (CH3COO)4进行ZrO2的包覆改性。TEM测试结果显示纳米级的ZrO2颗粒附着在LNMCO的表面。包覆质量分数为1.5%的ZrO2包覆样品的首圈库伦效率和放电比容量有着显著提升,在室温下其首圈库伦效率和放电比容量(电流密度:20 mA·g-1,电压:2.0~4.8 V)分别为87.2%,279.3 mAh·g-1,而原样则为75.1%,224.1 mAh·g-1,循环100圈之后,1.5% ZrO2包覆样品的放电比容量为248.3 mAh·g-1,容量保持率为88.9%,高于原样的195.9 mAh·g-1和87.4%。  相似文献   
7.
In this paper, we have given the spin states of two-photon, which are expressed by the quadratic combination of two single-photon spin states, and given all entanglement states of two-photon from the spin states of two-photon. The new expression of two-photon entanglement states should be used in quantum computation and quantum communication.  相似文献   
8.
High spin states in 107Ag are studied via the 100Mo(11B, 4n)107Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme has been updated and a new negative band belonging to 107Ag is identified. The new negative side band has been constructed and its configuration is tentatively assigned to πg9/2 νh11/2(g7/2/d5/2).  相似文献   
9.
微腔的谐振腔长度直接影响微腔有机电致发光器件(MOLED)的发光特性,根据微腔器件的相关计算公式运用传输矩阵法,分别对微腔长度L=λ/2和L=λ(λ:中心波长)时,在微腔内不同位置激子复合发光的电致发光谱(EL)进行模拟计算和比较。发现:微腔长度为L=λ/2时,峰值均为520nm,半峰全宽均为17nm,激子处在微腔的中心位置时,峰值强度和积分强度均为最大。L=λ时,激子在腔内不同位置时,峰值均为520nm,半峰全宽均12nm,在腔的中心区域时,与L=λ/2时正好相反,峰值强度和积分强度最小。分析后判断是因为两种长度的微腔内电场强度分布不同,激子位于腔内电场的最大值处发光性能最好。说明要制作出高效率的MOLED,要区别不同谐振腔长度,并使激子处于腔内电场最大处。  相似文献   
10.
High spin states of 128La have been studied through the fusion-evaporation reaction 118Sn(14N,4n) 128La at a beam energy of 69 MeV. A positive-parity side band with the same configuration as that of the yrast band has been identified. Moreover, it is noted that the energy separation △E(I) = E(I)side-E(I)yrast of all doublet bands reported in odd-odd nuclei in the A~130 mass region exhibit a staggering pattern systematically, and they stagger up at even-spin and stagger down at odd-spin.  相似文献   
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