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Clemens G. Raab Georg Regensburger Jamal Hossein Poor 《Journal of Pure and Applied Algebra》2021,225(5):106564
A formal computation proving a new operator identity from known ones is, in principle, restricted by domains and codomains of linear operators involved, since not any two operators can be added or composed. Algebraically, identities can be modelled by noncommutative polynomials and such a formal computation proves that the polynomial corresponding to the new identity lies in the ideal generated by the polynomials corresponding to the known identities. In order to prove an operator identity, however, just proving membership of the polynomial in the ideal is not enough, since the ring of noncommutative polynomials ignores domains and codomains. We show that it suffices to additionally verify compatibility of this polynomial and of the generators of the ideal with the labelled quiver that encodes which polynomials can be realized as linear operators. Then, for every consistent representation of such a quiver in a linear category, there exists a computation in the category that proves the corresponding instance of the identity. Moreover, by assigning the same label to several edges of the quiver, the algebraic framework developed allows to model different versions of an operator by the same indeterminate in the noncommutative polynomials. 相似文献
3.
Behnam Reza Roghani-Mamaqani Hossein Salami-Kalajahi Mehdi 《Journal of Thermal Analysis and Calorimetry》2019,135(6):3311-3319
Journal of Thermal Analysis and Calorimetry - Effect of different chain extenders, silica nanoparticle loading, and using sol–gel method on the thermal properties of polyurethane (PU) hybrid... 相似文献
4.
Esmaeili Hossein Armaghani T. Abedini A. Pop I. 《Journal of Thermal Analysis and Calorimetry》2019,135(6):3247-3257
Journal of Thermal Analysis and Calorimetry - The nanofluid is a mixture of base fluid and solid nanoparticles in nanosize. The heat transfer generated by the nanofluid is more than the base fluid... 相似文献
5.
ABSTRACTUsing density functional theory calculations, we investigate the gas sensing performance of B-, N-doped and BN-codoped C60 fullerenes towards NO and NO2 molecules. The calculated adsorption energies and net charge-transfer values indicate that NO and NO2 molecules have a stronger interaction with the BN-codoped fullerenes compared to the B- or N-doped ones. It is also found that the electronic properties of the BN-codoped C60 exhibit a larger sensitivity towards NO and NO2 molecules. An increase in the concentration of doped/co-doped B and N atoms tends to weaken the gas sensing ability of these systems. 相似文献
6.
Chromene substructure is an important structural motif present in a variety of medicines, natural products, and materials showing biological activities. Here, a simple and convenient procedure for the synthesis of 3,4-dihydropyrano[3,2-c]chromene derivatives is described. For this purpose, Fe3O4 nanoparticles supported on β-cyclodextrin-guanidine were successfully prepared and used as catalyst. The structure of this catalyst was assigned by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis, and vibrating sample magnetometer techniques. The prepared nanocomposites were used as a highly active, heterogeneous, and reusable nanocatalyst for the one-pot, three-component reaction of 4-hydroxycoumarin, aromatic aldehydes, and ethyl cyanoacetate. This method has advantages such as mild conditions, high yields, easy workup and simple purification of products, little catalyst loading, cost efficiency, and reusability of the catalyst. 相似文献
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Jalal Hassan Gholam-Reza Shams Hossein Meighani 《Journal of Analytical Chemistry》2015,70(12):1495-1500
10.
Sorayya Ghasemi JokoPriyanto Wibowo Hossein Amini-khoei 《Natural product research》2019,33(12):1828-1831
For more effectiveness and overcoming the drug resistance Chemotherapy agents, the combination treatment is raised. Flavonoids with different anti-cancer effects are an appropriate choice as lead compounds. Over expressed MiR-21 in prostate cancer is associated with metastasis and drug resistance to chemotherapy with Docetaxel. In this study, the anticancer effect of 4′, 5, 7-Trihydroxy-3′, 5′-dimethoxyflavone (Tricin) was investigated with Docetaxel on PC3 cell line. Tricin was initially isolated from the Allium atroviolaceum by column chromatography and recrystallization method. The chemical structure of isolate was elucidated by spectroscopic techniques. IC50 of Tricin and Docetaxel were assessed 117.5 ± 4.4 μM and 0.1 ± 0.02 nM by MTT assay, respectively. Analysis of results indicates the synergistic effect of combination therapy on decreased proliferation. MiR-21 in treated cells with Tricin significantly decreased compared to control cells. So, Tricin can be effective in the reduction of metastasis and drug resistance of Docetaxel. 相似文献