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Abstract: A sediment numerical model was embedded into a wave-tide-circulation coupled model to simulate the transport processes of the Yellow River-derived sediment considering the wave-induced vertical mixing (Bv) and the wave-current coupled bottom shear stress (BSS). Numerical results show that the main stream of the Yellow River-derived sediment moves first eastward off the northern Shandong Peninsula and then southward into the South Yellow Sea all year round. In spring, the sediment moves northeastward in the Bohai Sea. In summer, there is a northeastward branch of sediment in the Bohai Sea off the west coast of the Liaodong Peninsula, while the main part goes eastward to the Yellow Sea. The Yellow River-derived sediment transport from the Bohai Sea to the North Yellow Sea across the Bohai Strait is mainly limited to the top 10 m, and with a maximum centered at 37.9°N in summer. The transport from the North Yellow Sea to the South Yellow Sea across the transect of 37°N is mainly in the 0–30 m layer with a maximum around 123.7°E in autumn. The simulated Yellow River-discharged sediment deposits along the Shandong Peninsula and between 20 and 30 m isobaths in the Yellow Sea, which is consistent with observation. If surface waves are not considered in the model, the sediment deposits westward to the nearshore area in the South Yellow Sea. The sediment would deposit further southward in the numerical experiment results without wind influence. In the numerical experiment of no tide, there is hardly any sediment deposited on the Yellow Sea floor, while in the Bohai Sea most of the sediment is transported southward and northwestward around the river mouth instead of eastward as in the Control Run, indicating the tides play a key role in forming the deposition pattern. [Copyright &y& Elsevier]

Abstract: Piezomodulated reflectance (PzR) spectroscopy has been used to study the InAs/In0.15Ga0.85As quantum dots-in-a-well (DWELL) samples in the temperature range of 70–300K. The optical transitions from ground state to excited states in InAs DWELL were observed. The heavy- and light-hole transitions from the hybrid quantum well (HQW) were identified by combining the one-dimensional effective mass approximation (EMA) with the selected modulation effect in PzR spectrum. A remarkable red shift of the ground state has been observed in the InAs DWELL with optimized growth of In0.15Ga0.85As quantum well layers. Cooling both DWELL samples produces an abnormal broadening of the QD transitions in PzR spectra. [Copyright &y& Elsevier]

Abstract: Piezomodulated reflectance (PzR) spectra at 77 and 300K have been measured for InAs/In0.15Ga0.85As dots-in-a-well and a conventional InAs/GaAs quantum dots. The optical features of both samples were well resolved and confirmed by photoluminescence results. Numerical calculations are in good agreement with the experimental results. The transitions in sandwiched structure formed by InAs wetting layer and In0.15Ga0.85As/GaAs quantum well supports the model of strain-driven alloy decomposition. The abnormal intensity between heavy-hole-type and light-hole-type transition of such sandwiched structure in PzR spectra has been discussed in terms of increased hydrostatic strain in In0.15Ga0.85As/GaAs quantum well. [Copyright &y& Elsevier]

Abstract: Signatures associated with electronic states confined in two strained In x Ga1–x As/GaAs single quantum wells have been observed in its piezomodulated (PzR) and photomodulated (PR) reflectivity spectra. One comparison of the relative intensity between 11H and 11L signatures in PzR of GaAs/In0.14Ga0.86As SQW emphasizes the contribution of strain dependence of energies of the confined states; the other comparison of corresponding confined states between PzR and PR spectra in both samples has been introduced to interpret the discrepancy of the relative intensity in term of modulated strength, and the calculated ratio of energy shifts induced by strain to that of produced by surface electric field agree with the experimental observation. [Copyright &y& Elsevier]