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1.
We give several equivalent characterisations of left (and hence, by duality, also of right) supported algebras. These characterisations are in terms of properties of the left and the right parts of the module category, or in terms of the classes L0 and R0 which consist respectively of the predecessors of the projective modules, and of the successors of the injective modules. 相似文献
2.
Peng Li Assem Abolmaaty Christine D’Amore Stefanie Demming Constantine Anagnostopoulos et al. 《Applied biochemistry and biotechnology》1992,36(2):88-96
Materials and Methods
Synthesis of thionyl chloride-activated succinamidopropyl-glass beads 相似文献
3.
Catalytic autoimmune antibodies from patients with antiphospholipid (aPL) antibodies were purified using histidyl-aminohexyl-sepharose gel. The sera were loaded on the columns equilibrated with 25 mM MOPS buffer pH 7.4 and the absorbed proteins were eluted by adding 0.2 M NaCl in the equilibrating buffer. Antibodies purity was evaluated by SDS-PAGE. The purified immunoglobulins G from patients with (aPL) sera by histidyl-aminohexyl-sepharose show DNA-degrading activity of the plasmid pUC19 DNA and catalytic activity in hydrolyzing the peptide substrate Pro-Phe-Arg-7-amido-4-methylcoumarin. 相似文献
4.
Mezna Saleh Altowyan Saied M. Soliman Matti Haukka Nora Hamad Al-Shaalan Aminah A. Alkharboush Assem Barakat 《Molecules (Basel, Switzerland)》2022,27(13)
In the present work, a novel heterocyclic hybrid of a spirooxindole system was synthesized via the attachment of ferrocene and triazole motifs into an azomethine ylide by [3 + 2] cycloaddition reaction protocol. The X-ray structure of the heterocyclic hybrid (1″R,2″S,3R)-2″-(1-(3-chloro-4-fluorophenyl)-5-methyl-1H-1,2,3-triazole-4-carbonyl)-5-methyl-1″-(ferrocin-2-yl)-1″,2″,5″,6″,7″,7a″-hexahydrospiro[indoline-3,3″-pyrrolizin]-2-one revealed very well the expected structure, by using different analytical tools (FTIR and NMR spectroscopy). It crystallized in the triclinic-crystal system and the P-1-space group. The unit cell parameters are a = 9.1442(2) Å, b = 12.0872(3) Å, c = 14.1223(4) Å, α = 102.1700(10)°, β = 97.4190(10)°, γ = 99.1600(10)°, and V = 1484.81(7) Å3. There are two molecules per unit cell and one formula unit per asymmetric unit. Hirshfeld analysis was used to study the molecular packing of the heterocyclic hybrid. H···H (50.8%), H···C (14.2%), Cl···H (8.9%), O···H (7.3%), and N···H (5.1%) are the most dominant intermolecular contacts in the crystal structure. O···H, N···H, H···C, F···H, F···C, and O···O are the only contacts that have the characteristic features of short and significant interactions. AIM study indicated predominant covalent characters for the Fe–C interactions. Also, the electron density (ρ(r)) at the bond critical point correlated inversely with the Fe–C distances. 相似文献
5.
Mohammad Shahidul Islam M. Ali Abdullah Mohammed Al-Majid Abdullah Saleh Alamary Saeed Alshahrani Sammer Yousuf Muhammad Iqbal Choudhary Assem Barakat 《Molecules (Basel, Switzerland)》2021,26(8)
The Friedel–Crafts reaction between substituted indoles as nucleophiles with chalcones-based benzofuran and benzothiophene scaffolds was carried out by employing a highly efficient bimetallic iron–palladium catalyst system. This catalytic approach produced the desired bis-heteroaryl products with low catalyst loading, a simple procedure, and with acceptable yield. All synthesized indole scaffolds 3a–3s were initially evaluated for their cytotoxic effect against human fibroblast BJ cell lines and appeared to be non-cytotoxic. All non-cytotoxic compounds 3a–3s were then evaluated for their anticancer activities against cervical cancer HeLa, prostate cancer PC3, and breast cancer MCF-7 cell lines, in comparison to standard drug doxorubicin, with IC50 values 1.9 ± 0.4 µM, 0.9 ± 0.14 µM and 0.79 ± 0.05 µM, respectively, and appeared to be moderate to weak anticancer agents. Fluoro-substituted chalcone moiety-containing compounds, 3b appeared to be the most active member of the series against cervical HeLa (IC50 = 8.2 ± 0.2 µM) and breast MCF-7 cancer cell line (IC50 = 12.3 ± 0.04 µM), whereas 6-fluroindol-4-bromophenyl chalcone-containing compound 3e (IC50 = 7.8 ± 0.4 µM) appeared to be more active against PC3 prostate cancer cell line. 相似文献
6.
Some halogen-doped calcium borate glasses containing iron have been prepared according to the percentage molar composition [(30 – x) CaO · x CaX2 · 10 Fe2O3 · 60 B2O3] and annealed. It is found that the conduction in the semiconducting glasses is mainly due to electronic conduction. The results show that the halide ions may be introduced as modifiers for CaX2 concentration < 10 mol% (X >= F, Cl, and Br) but they are network formers at CaX2 > 10 mol%. It is proposed that at 10 mol% the network structure for all glasses seems to be the same. The dependence of resistivity on the halide ions concentration as well as the slight variation of activation energies, could be explained on the basis of electron-lattice interaction. Mathematical expressions for fitting and describing the dependence of resistivity on CaX2 concentration are deduced and formulated by the following equations: ϱ = ϱ0 exp [± ac(1 – bc)] and ϱ ϱ= ±10 exp [± a′c(1 – b′c)] for the two regions around the critical concentration. 相似文献
7.
Saied M. Soliman Assem Barakat Hazem A. Ghabbour 《Journal of Coordination Chemistry》2017,70(8):1339-1356
A new highly distorted hexacoordinated silver(I) complex [AgL2NO3] with 2-(bis(methylthio)methylene)-1-phenylbutane-1,3-dione (L) as ligand is synthesized and characterized using elemental analysis, FTIR, NMR, and X-ray single-crystal structure analysis. The ligand (L) and the nitrate group act as bidentate ligands. The geometry around the silver ion has an intermediate configuration between a trigonal prism (TP) and an octahedron (OCT). Continuous shape measure (CShM) analysis indicated a closer configuration to TP than OCT. Experimentally and theoretically, the Ag–S bonds are shorter than any of the Ag–O bonds, indicating a stronger interaction between Ag+ (soft metal) and S-atom as a softer site than oxygen. Natural bond orbital (NBO) analyses showed higher interaction energies between the S-atom lone pairs and the Ag–antibonding NBO (8.61–31.39 kcal/mol) than LP(O)→Ag (3.48–11.46 kcal/mol). The acceptor antibonding NBO of the Ag atom has mainly s-orbital character. The Ag atom has a natural charge of +0.7579 e at the experimental structure, suggesting that negative charge was transferred from the ligand (0.0666 e) and nitrate (0.1090 e) to the Ag ion. Using Hirshfeld surface analysis, the important intermolecular interactions between molecular units within the crystal lattice of the ligand and its Ag-complex were analyzed and compared. 相似文献
8.
E.E. Assem 《Physica B: Condensed Matter》2011,406(3):421-425
The effect of halide ions on density, electrical, magnetic and crystallization kinetics for (20X-50P2O5-30V2O5) mole% has been investigated, where X=CaO, CaF2, CaCl2 and CaBr2. Halide ions reduce the glass transition temperature, crystallization temperature and activation energy of crystallization. Density, electrical conductivity and magnetic susceptibility increase while molar volume, glass thermal stability and interatomic distance between transition metal ions decrease as the halide ions replace the oxygen ions in these glasses. 相似文献
9.
The use of highly purified immunoglobulin became among the most powerful adopted strategies in therapeutic trials nowadays. Their role as immunomodulatory and anti-inflammatory agents has widened their scope of use. A novel continuous supermacroporous monolithic cryogels embedded with histidine-epoxy-activated-sepharose beads were synthetized as a new monolithic adsorbents for the separation of immunoglobulin G from human serum. The histidine-epoxy-activated-sepharose beads were embedded into the 2-hydroxyethyl methacrylate (HEMA) cryogels present in frozen aqueous solution inside a plastic syringe. The microstructure morphology of the cryogels was characterized by swelling measurement and scanning electron microscopy. The adsorption of human IgG on the histidine-epoxy-activated-sepharose beads pHEMA cryogels appeared to follow the Langmuir–Freundlich adsorption isotherm model. The maximum IgG adsorption was observed at 4°C and pH 7.4 and was found to be 26.95 mg/g of cryogel which is close to that obtained experimentally (24.49 mg/g). The cryogels were used for several adsorption-desorption cycles without any negligible decrease in their adsorption capacity. 相似文献
10.
In this article, we establish a bijection between the set of mutation classes of mutation-cyclic skew-symmetric integral 3 × 3-matrices and the set of triples of integers (a, b, c) such that 2 ≤ a ≤ b ≤ c and ab ≥ c. We also give an algorithm allowing to verify whether a matrix is mutation-cyclic or not. We prove that given a, b, the two cases depend on whether c is large enough or not. 相似文献