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101.
E. Vass 《Zeitschrift für Physik B Condensed Matter》1993,90(4):401-405
The average energy loss rate and relaxation time of non-degenerate 2D-excitons interacting with the deformation- and piezoelectric potential of 3D acoustic bulk phonons are calculated perturbation theoretically as a function of the exciton temperature using the matrix elements previously derived in [1]. The energy loss rate limited by the acoustic deformation potential increases proportional toT
3
7/2
(T
3
3/2
) if the phonon energy is much larger (smaller) than the thermal energy of the excitons having the temperatureT
e
. It is shown, that the phonon wavevector componentq
z
perpendicular to the interface of the QW must be taken into account in the calculation of the total excitonic loss rate in order to obtain the energy relaxation time value of 30 ps recently estimated in [2] from photoluminescence intensity measurements. 相似文献
102.
为了实现采摘机器人在复杂的自然场景下正确识别树上果实,来完成果实采摘,研究了不同环境下柑橘的识别方法.针对复杂的自然环境的影响及传统方法的局限性,在可见光和近红外区域择选5个特征波长滤波片,采集得到5幅滤波后的图像,并利用光谱角分类算法完成柑橘识别.试验结果表明,在光照角度、光照强度等不同条件下,柑橘的识别准确度达到96%.研究表明,滤波片光谱图像技术结合光谱角分类算法可以有效地识别自然场景下的成熟柑橘. 相似文献
103.
Franklin Martinez Steffi Bandelow Gerrit Marx Lutz Schweikhard Albert Vass 《Hyperfine Interactions》2015,232(1-3):19-27
Ion traps are versatile tools for the investigation of gas-phase cluster ions, allowing, e.g., cluster-size selection and extended reaction times. Taking advantage of their particular storage capability of simultaneous trapping of electrons and clusters, Penning traps have been applied for the production of clusters with high negative charge states. Recently, linear radio-frequency quadrupole traps have been demonstrated to be another candidate to produce polyanionic clusters. Operation with rectangular, rather than harmonic, radio-frequency voltages provides field-free time slots for unhindered electron passage through the trap. Several aspects of electron-attachment techniques by means of Penning and radio-frequency traps are addressed and recent experimental results are presented. 相似文献
104.
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106.
Gábor E. Veress Ilona Vass Ern Pungor 《Fresenius' Journal of Analytical Chemistry》1987,326(4):317-319
Summary Analytical chemical methods as systems produce chemical information about the material to be analyzed. Analytical chemical systems as semiosis consist of analytical signal production and analytical chemical signal interpretation and produce chemical information by inference in an indirect way through analytical information. From the logical point of view the chemical information produced by analytical chemical systems is only credible. Generalizing the results the idea of diagnostic systems can be introduced and the analytical chemical methods as systems are a special type of diagnostic systems.
Presented at the First International Symposium on History and Philosophy in Analytical Chemistry, Vienna, November 22–23, 1985 相似文献
Chemisch-analytische Systeme zur Erlangung chemischer Informationen
Presented at the First International Symposium on History and Philosophy in Analytical Chemistry, Vienna, November 22–23, 1985 相似文献
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