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991.
992.
Ling Miao Xiaoyu Qian Dazhang Zhu Ting Chen Guchuan Ping Yaokang Lv Wei Xiong Yafei Liu Lihua Gan Mingxian Liu 《中国化学快报》2019,30(7):1445-1449
A novel and effective strategy to fabricate hierarchical porous carbons for supercapacitors is developed via in-situ activation of interpenetrating polymer networks obtained from simultaneous polymerization of the monomers for two polymeric networks. 相似文献
993.
本工作在沟槽型台阶衬底上用直流磁控溅射法外延生长YBa2Cu3O7-δ(YBCO)超导薄膜后,制备出台阶结和射频超导量子干涉器(rfSQUID).液氮中器件的磁通灵敏度和磁场灵敏度分别达到2.0×10-4Φ0/Hz和294fT/Hz.涂有真空导热硅脂作保护层的器件,至今寿命已达10个月,经历了30次以上(个别器件达50次)测试过程中从液氮到室温的冷热循环,性能没有明显的变化,表现出很好的稳定性.通过研究,解决了制备rfSQUID器件工艺过程中存在的一些问题,提高了制备器件的可重复性,得到高性能器件的成品率达到30%~50%. 相似文献
994.
一般Lurie型控制系统的鲁棒绝对稳定性 总被引:9,自引:1,他引:9
本文得到一般的Lurie类型非线性控制系统的鲁棒绝对稳定性的充分条件;同时,给出一些例子说明本文结果的有效性. 相似文献
995.
996.
Seng Khoon Teh Wei Zheng Khek Yu Ho Ming Teh Khay Guan Yeoh Zhiwei Huang 《Journal of Raman spectroscopy : JRS》2009,40(8):908-914
Raman spectroscopy is a molecular vibrational spectroscopic technique that is capable of optically probing the biomolecular changes associated with neoplastic transformation. The purpose of this study was to apply near‐infrared (NIR) Raman spectroscopy for differentiating dysplasia from normal gastric mucosa tissue. A total of 65 gastric mucosa tissues (44 normal and 21 dysplasia) were obtained from 35 patients who underwent endoscopy investigation or gastrectomy operation for this study. A rapid NIR Raman system was utilized for tissue Raman spectroscopic measurements at 785‐nm laser excitation. High‐quality Raman spectra in the range of 800–1800 cm−1 can be acquired from gastric mucosa tissue within 5 s. Raman spectra showed significant differences between normal and dysplastic tissue, particularly in the spectral ranges of 850–1150, 1200–1500 and 1600–1750 cm−1, which contained signals related to proteins, nucleic acids and lipids. The diagnostic decision algorithm based on the combination of Raman peak intensity ratios of I875/I1450 and I1208/I1655 and the logistic regression analysis yielded a diagnostic sensitivity of 90.5% and specificity of 90.9% for identification of gastric dysplasia tissue. This work demonstrates that NIR Raman spectroscopy in conjunction with intensity ratio algorithms has the potential for the noninvasive diagnosis and detection of precancer in the stomach at the molecular level. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
997.
偶氮金属螯合物薄膜是一类新型光信息存储和光学非线性材料。通过旋涂法在单晶硅上制备了三种新型偶氮染料:2-(4-甲革-2-噻唑基偶氮)-5-二乙基胺苯酚(MTADP)掺杂聚合物,MTADP的镍螯合物(Ni-MTADP)和锌螯合物(Zn-MTADP)薄膜。利用宽谱扫描全自动椭圆偏振光谱仪测定了上述薄膜的椭偏光谱,获得了三种薄膜在400—700nm波段的复折射率、复介电常量和吸收系数。两种金属螯合物薄膜的共振波长比非螯合物薄膜红移了60—70nm;光学常数和吸收系数在峰值的数值也发生了明显的变化。由于这两种螯合物具有不同的立体结构,Ni-MTADP薄膜的共振波长比Zn-MTADP有10nm的红移。 相似文献
998.
Ming Xian Liu Li Hua Gan Ci Tian Jian Chun Zhu Zi Jie Xu Zhi Xian Hao Long Wu Chen 《中国化学快报》2009,20(1):123-126
We demonstrated a simple and effective dual-templating approach for the synthesis of hierarchically mesocellular carbon foams by using nonionic surfactant of sorbitan monooleate and silica colloid particles as sacrificial templates, and resorcinol/ formaldehyde as carbon source. The representative carbon foam has dual mesopore sizes of 4 and 10 nm, and possesses the specific surface area of 580 m2/g and the total pore volume of 0.80 cm3/g. 相似文献
999.
Shaobo Gan Ming Li Sergey B. Tikhomirov 《Journal of Dynamics and Differential Equations》2016,28(1):225-237
We call that a vector field has the oriented shadowing property if for any \(\varepsilon >0\) there is \(d>0\) such that each \(d\)-pseudo orbit is \(\varepsilon \)-oriented shadowed by some real orbit. In this paper, we show that the \(C^1\)-interior of the set of vector fields with the oriented shadowing property is contained in the set of vector fields with the \(\Omega \)-stability. 相似文献
1000.
A laser pulse-induced microbump method that aims to measure the elongation rate of nanofilms is proposed. The sample structure is designed as “substrate/active layer/nanofilm” and the laser pulse is used as energy source to heat the active layer and to create microbump. These cause the nanofilm to expand and elongate. The surface area and length change of nanofilm is calculated by measuring the deflections and diameters of the microbumps, as well as to obtain the elongation rate of the nanofilms. A series of microbumps with different deflections are obtained. The deflections are measured precisely by atomic force microscopy (AFM) by taking AgOx and ZnS-SiO2 as the active layer and nanofilm, respectively, and by controlling pulse laser parameters. The line elongation rate and plane elongation rate of ZnS-SiO2 nanofilm are measured at thickness of only 10 nm. Results show that both the two elongation rates linearly increases with laser power from 3.2 to 5.2 mW. Plane elongation rate is a little higher than the line elongation rate at the same laser power. The rupture at 5.4 mW laser power corresponds to fracture strength of the film. The maximum line elongation rate and plane elongation rate are 13.241% and 19.766%, respectively. This method applies a reproducible and efficient method for its applications in the near future. 相似文献