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1.
Field Emission from Silicon Nanocrystallite Films with Compact Alignment and Uniform Orientation 下载免费PDF全文
Patterned silicon nanocrystallite (SINC) films were fabricated on (100) orientation p-type boron-doped sificon wafer by the hydrogen ion implantation technique and the anodic etching method. The efficient field emission with low turn-on field of about 3.5V/μm at current density of 0.1μA/cm^2 was obtained. The emission current density from the SiNC films reached 1mA/cm^2 under a bias field of about 9.1V/μm. The experimental results demonstrate that there are great potential applications of the SiNC films for fiat panel displays. A surface treatment with hydrogen plasma was performed on the SiNC films and a significant improvement of emission properties was achieved. 相似文献
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羟基乙叉二膦酸双(二烷基锡)的合成包光林(安徽医科大学化学教研室合肥230032)资学理,李康龄,李良驷(云南师范大学化学系昆明650092)有机膦酸的有机锡衍生物具有很强的生理活性,作为杀虫剂,杀螨剂,表面消毒剂及聚烯烃的热稳定剂已在工农业生产中得... 相似文献
3.
马心血红蛋白在氧化铟电极上的直接电子传递反应 总被引:1,自引:0,他引:1
马心血红蛋白在氧化铟电极上的直接电子传递反应杨秀娟,菊,陆天虹(中国科学院长春应用化学研究所电分析化学开放实验室,长春,130022)关键词血红蛋白,氧化铟电极,循环伏安法蛋白质与电极之间的电子转移在某种程度上类似于生物体内蛋白质分子之间的电子转移过... 相似文献
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通过含有吲哚底物的分子内氧化偶联反应,成功地构建了Communesin家族生物碱的螺吲哚啉季碳中心,从而完成了(-)-Communesins A,B和F的对映选择性合成.接下来我们发展了分子内氧化偶联/缩合串联反应策略,得到了天然产物(-)-Vincorine的核心四环骨架,然后再经过五步转化完成了Vincorine的全合成.从药物化学角度来看,分子内氧化偶联/缩合串联提供了一个快速方便地合成含有多环吲哚啉骨架的方法.采用相同的串联反应策略,我们分别从色胺衍生的β-酮酸酰胺和丙二酸二酰胺出发,一步构建了多环螺吲哚啉和多环吲哚啉并吡咯环骨架分子. 相似文献
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We systematically investigate the motion of slowly moving
matter--wave gap solitons in a nonlinear potential, produced by the
weak random spatial variation of the atomic scattering length. With
the weak randomness, we construct an effective-particle theory to
study the motion of gap solitons. Based on the effective-particle
theory, the effect of the randomness on gap solitons is obtained, and
the motion of gap solitons is finally solved. Moreover, the analytic
results for the general behaviours of gap soliton motion, such as the
ensemble-average speed and the reflection probability depending on
the weak randomness are obtained. We find that with the increase of
the random strength the ensemble-average speed of gap solitons
decreases slowly where the reduction is proportional to the variance
of the weak randomness, and the reflection probability becomes
larger. The theoretical results are in good agreement with the
numerical simulations based on the Gross--Pitaevskii equation. 相似文献
7.
Structural behaviors of silicon and germanium clusters under the recently proposed modified Stillinger-Weber (SW) potential have been studied by molecular dynamics method along with the con-jugate-gradient optimization. Since the SW potentials have been derived from the properties of bulk materials, it gives relatively large discrepancy when the cluster number is small, e.g. n=3 and 4. When n>4, the ground-state structures under the modified SW potential are close to that from the first-principle calculation. The binding energies are also improved under the modified SW potential. These results may be attributed to the relative enhancement of the two-body term over the three-body term in the modified SW potential, which leads to structures with a preferential coordination number 4. Structural behaviors of germanium clusters are similar to those of silicon. 相似文献
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采用常规水溶液法在低热环境下得到了一种新的基于砷钨酸和Mn~Ⅲ的夹心型化合物,该化合物为单斜晶系,空间群为P2_1/c,晶胞参数为a=2.041 26(8)nm,b=3.227 58(8)nm,c=1.325 35(5)nm,β=94.427(3)°,V=8.705 8(5)nm~3,Z=4;分子式为(NH_4)_(10)[(MnH_2O)_2WO_2(AsW_9O_(33))_2]·3.5H_2O.性质分析表明,标题化合物对Hela细胞具有较高的抗肿瘤活性,可以作为潜在的抗肿瘤药物模型. 相似文献