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991.
The synthesis of 3′-fluoro-4′-amino-hexitol nucleosides with a uracil and cytosine nucleobase was performed. The synthesis started from 1,5:2,3-dianhydro-4,6-benzylidene-allitol and afforded the target compounds in 15 steps. These protected hexitol nucleosides are valuable building blocks for the preparation of a new class of oligonucleotides.  相似文献   
992.
The 2,5-diketopiperazine (DKP) moiety is a core feature of many natural products and medicinally relevant scaffolds. As part of our efforts directed towards a total synthesis of penicisulfuranol B, we have developed and report herein: (1) the preparation of an N-hydroxy diketopiperazine intermediate accessible via a molybdenum-mediated oxidation of a parent diketopiperazine, and (2) further synthetic studies leading to a novel spirocyclic dihydrobenzofuran-containing diketopiperazine.  相似文献   
993.
994.
Burdovitsin  V. A.  Oks  E. M. 《Russian Physics Journal》2020,62(11):2011-2014
Russian Physics Journal - The paper shows that the potential of isolated metal or dielectric target under electron-beam irradiation in medium vacuum can be estimated through measuring the...  相似文献   
995.
Russian Physics Journal - The results of investigations of the properties of cyanine dye dimers in the triplet state are presented. The formation of dimers is demonstrated as two absorption bands...  相似文献   
996.
ABSTRACT

In this paper, we present a systematic roadmap for developing a robust and parallel multi-material reactive hydrodynamic solver that integrates historically stable algorithms with new and current modern methods to solve explosive system design problems. The Ghost Fluid Method and Riemann solvers were used to enforce appropriate interface boundary conditions. Improved performance in terms of computational work and convergence properties was achieved by modifying a local node sorting strategy that decouples ghost nodes, allowing us to set material boundary conditions via an explicit procedure, removing the need to solve a coupled system of equations numerically. The locality and explicit nature of the node sorting concept allows for greater levels of parallelism and lower computational cost when populating ghost nodes. Non-linear numerical issues endemic to the use of real Equations of State in hydro-codes were resolved by using more thermodynamically consistent forms allowing us to accurately resolve large density gradients associated with high energy detonation problems at material interfaces. Pre-computed volume tables were implemented adding to the robustness of the solver base.  相似文献   
997.
Molecular Diversity - As one of the hot topics in the epigenetic studies, histone deacetylases inhibitors (HDACIs) have been introduced to treat a variety of diseases such as cancer, immune...  相似文献   
998.
Physics of Particles and Nuclei Letters - Gamma spectrometry is applied for measurement of natural radioactivity by Hyper-pure germanium (HPGe) systems during the application of bioleaching optimum...  相似文献   
999.
Journal of Thermal Analysis and Calorimetry - In the present study, a set of experiments were accomplished to appraise the thermal performance and heat transfer of n-pentane-acetone and...  相似文献   
1000.
Journal of Thermal Analysis and Calorimetry - The effect on the entropy production and MHD convection of the hybrid nanofluid Al2O3–Cu/water (water with Cu and Al2O3 nanoparticles) in a...  相似文献   
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