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151.
华隆公司拟在万顷沙西十二涌与十三涌之间兴十三涌3000T级油轮港口码头。本文分析了该河段水文泥沙的特性、河道演变趋势及河段稳定性,通过物理模型试验研究及对航道、港池的回淤计算分析,预测工程建成后引起局部水流流态的变化,对水道泄洪、潮排、潮灌的影响,以及港池、航道建成后的泥沙淤积情况。 相似文献
152.
153.
154.
Heat‐treatment is one of the most commonly used processes in food preparation technology. An understanding of the thermodynamics of protein stability and of conformational changes of proteins, acquired through the measurement of the denaturation temperature, is therefore of particular importance. This paper attempts to shed light on the interpretation of recent calorimetric data on the thennal denaturation of bovine β‐lactoglobulin, α‐lactalbumin, and bovine serum albumin by showing that thermodynamic parameters of heat‐induced unfolding, measured by differential scanning calonmetry, are closely related to the prevailing chemical conditions such as pH, concentration of ions, protein purity, and protein concentration. 相似文献
155.
Seung Yol Jeong Sung Hun Kim Joong Tark Han Hee Jin Jeong Soo Yeon Jeong Geon‐Woong Lee 《Advanced functional materials》2012,22(15):3307-3314
A novel route to preparing highly concentrated and conductive reduced graphene oxide (RGO) in various solvents by monovalent cation–π interaction. Previously, the hydrophobic properties of high‐quality RGO containing few defects and oxygen moieties have precluded the formation of stable dispersion in various solvents. Cation–π interaction between monovalent cations, such as Na+ or K+, and six‐membered sp2 carbons on graphene were achieved by simple aging process of graphene oxide (GO) nanosheets dispersed in alkali solvent. The noncovalent binding forces introduced by the cation–π interactions were evident from the chemical shift of the sp2 peak in the solid 13C NMR spectra. Raman spectra and the I‐V characteristics demonstrated the interactions in terms of the presence of n‐type doping effect due to the adsorption of cations with high electron mobility (39 cm2/Vs). The RGO film prepared without a post‐annealing process displayed superior electrical conductivity of 97,500 S/m at a thickness of 1.7 μm. Moreover, mass production of GO paste with a concentration as high as 20 g/L was achieved by accelerating the cation–π interactions with densification process. This strategy can facilitate the development of large scalable production methods for preparing printed electronics made from high‐quality RGO nanosheets. 相似文献
156.
A universal low optimum doping concentration of below 5% was demonstrated in phosphorescent organic light-emitting diodes (PHOLEDs) by managing the energy levels of charge transport materials. The device performances of PHOLEDs could be optimized at a low doping concentration of 3% irrespective of the host material in the emitting layer. The suppression of charge trapping and hopping by the dopant through charge transport layer engineering optimized the device performance at low doping concentration. In addition, it was revealed that PHOLEDs with low optimum doping concentration show better quantum efficiency, low efficiency roll-off and low doping concentration dependency of the device performance. 相似文献
157.
158.
本文主要研究了根际pH值对烤烟叶片化学成分的影响。结果表明,随根际pH升至8.0,叶片中的总氮、磷、钾及灰分含量呈增加趋势,蛋白质、铜、锌、锰、氯含量降低。pH在6.5~7.5范围内变化时,还原糖含量保持相对稳定,超出此范围则明显升高。pH6.0~7.0的烟叶有较高的烟碱含量。pH8.5的烟叶化学成分不协调。叶片中的氨基酸含量浓度也受到根际pH的显著影响。 相似文献
159.
Effect of abrasive particle concentration on material removal rate (MRR), MRR per particle and the surface quality in the preliminary chemical mechanical polishing (CMP) of rough glass substrate was investigated. Experimental results showed that the MRR increases linearly with the increase of abrasive concentration and reaches to the maximum when the abrasive concentration is 20 wt.%, and then tends to be stable. When the abrasive concentration increases from 2 to 5 wt.%, the MRR per particle increases greatly and reaches a peak. Then the MRR per particle decreases almost linearly with the increase of the abrasive concentration. The root mean squares (RMS) roughness almost decreases with increasing particle concentration. In addition, in situ coefficient of friction (COF) was also conducted during the polishing process and the zeta potentials of abrasive particles in slurry with different solid concentration were also characterized. Results show that COF value is not related to zeta potential but be sensitive to glass surface conditions in terms of rough peaks in preliminary polishing of glass substrate. 相似文献
160.
Concentrations of native and gold defects in HgCdTe from first principles calculations 总被引:1,自引:0,他引:1
We have studied the defect formation energies of the various native (vacancies, interstitials, and antisites) and Au defects
in Hg1−xCdxTe using density functional-based total energy calculations with ultrasoft pseudo-potentials. These studies are important
for infrared (IR) detection technology where the device performance can be severely degraded because of defects. To calculate
formation energies, we modeled the neutral and charged defects using supercells containing 64 atoms. From the formation energies,
we have determined the defect concentrations as a function of stoichiometry and temperature. We find the prevalent neutral
defects to be Au at the Hg site (AuHg
), Hg vacancies (VHg
), and Te antisites (TeHg
). We have also explicitly studied charged defects and have found Te
Hg
2+
, Au
Hg
1−
, V
Hg
1−
, V
Hg
2−
, and V
Te
2+
to have low formation energies. We have identified AuHg
to be the prevalent Au defect, having concentrations several orders of magnitude greater than the other Au defects. We find
that the charge state of VHg is primarily (1−) or (2−) depending on the electronic chemical potential. 相似文献