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801.
802.
Soon Kil Ahn Nam Song Choi Byeong Seon Jeong Kye Kwang Kim Duck Jin Journ Joon Kyum Kim Sang Joon Lee Jung Woo Kim Chung Hong Sang‐Sup Jew 《Journal of heterocyclic chemistry》2000,37(5):1141-1144
A practical semi‐synthetic method of (S)‐7‐(2‐isopropylamino)ethylcamptothecin hydrochloride has been developed. The Mannich reaction of (S)‐7‐methylcamptothecin with isopropylamine hydrochloride in dimethyl sulfoxide as a formaldehyde source gave the desired product in moderate yield. 相似文献
803.
804.
We find the existence conditions for stationary dipole and tripole surface solitons formed at the interface of a nonlocal nonlinear medium and a lattice with linearly modulated frequency. We investigate how the degree of nonlocality, the depth, and the modulation frequency of the optical lattice field affect on the existence of the surface solitons and their dynamics. The relationship between the power and the model parameters is identified. The stability of the surface dipole and tripole solitons is numerically investigated. 相似文献
805.
Du-Cheng TsaiYen-Lin Huang Sheng-Ru LinDe-Ru Jung Shou-Yi ChangFuh-Sheng Shieu 《Applied Surface Science》2011,257(11):4923-4927
In this study, 15 nm-thick sputter-deposited TiVCr alloy thin films were developed as diffusion barrier layers for Cu interconnects. The TiVCr alloy film tends to form a solid solution and a simple crystal structure from the constituted elements. Under TEM, the 15 nm-thick as-deposited TiVCr alloy film was observed to have a dense semi-amorphous or nanocrystalline structure. In conjunction with X-ray diffraction, transmission electron microscopy, and energy-dispersive spectroscopy analyses, the Si/TiVCr/Cu film stack remained stable at a high temperature of 700 °C for 30 min. The electrical resistance of Si/TiVCr/Cu film stack remained as low as the as-deposited value. These indicated that the mixed TiVCr refractory elements’ alloy barrier layer is very beneficial to prevent Cu diffusion. 相似文献
806.
807.
Bis‐benzimidazolium salts were prepared successfully from commercially available and inexpensive o‐phenylenediamine through a series of simple reactions. The bis‐NHC‐Pd complexes prepared in situ can catalyze Suzuki‐Miyaura cross‐coupling reaction under very mild conditions in aqueous media with excellent yields. The efficiency of this reaction is demonstrated by its compatibility with a range of functional groups. Di‐ortho‐substituted biaryls could be accomplished in 89–99% yields. Moreover, the rigorous exclusion of air or moisture is not required in these transformations. 相似文献
808.
809.
Staszewski R. Staszewski R. B. Jung T. Murphy T. Bashir I. Eliezer O. Muhammad K. Entezari M. 《Solid-State Circuits, IEEE Journal of》2010,45(2):276-288
810.
To analyze the withdrawal force curve in the wetting balance curve, wetting balance tests using the 63Sn-37Pb and 96.5Sn-3.6Ag
eutectic solders were conducted by varying the immersion speed, sample perimeter, and solder temperature. The mechanism of
the withdrawal force curve was reviewed and a new method for calculating the surface tension of solders using the withdrawal
force curve was introduced. The results showed that the maximum point of the withdrawal force curve is generated when the
sliding solder meets the bottom corners of a sample and the contact angle is reduced to zero. The maximum withdrawal force
subtracted by end force can be expressed using force balance equation as F=pγ. Therefore, the surface tension of the solder
can be calculated by dividing the maximum withdrawal force by the sample parameter. 相似文献