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991.
S.A.A. Zaidi S. Rehan A. Zaidi Mohd. Shakir Mohammad Aslam Z.A. Siddiqi 《Polyhedron》1985,4(3):365-368
-Lanthanide(III) chlorosulphates, Ln(SO3Cl)3 (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er) have been synthesized by solvolytic reaction of chlorosulphuric acid on the corresponding benzoates. The low conductivity values and the IR spectra of these compounds suggest a cation-anion interaction leading to covalent bonding. The bands observed in the reflectance spectra and the values of magnetic moments may indicate a coordination number of 6 for these metals, with bidentate chlorosulphate groups. 相似文献
992.
The ΛΛ binding energy (B
ΛΛ) of the s- and p-shell hypernuclei are calculated variationally in the cluster model and multidimensional integrations are
performed using Monte Carlo. A variety of phenomenological Λ-core potentials consistent with the Λ-core energies and a wide
range of simulated s-state ΛΛ potentials are taken as input. The B
ΛΛ of ΛΛ6He is explained and ΛΛ5He and ΛΛ5H are predicted to be particle stable in the ΛΛ-core model. The results for s-shell hypernuclei are in excellent agreement
with those of non-VMC calculations. The ΛΛ10Be in ΛΛαα model is overbound for combinations of ΛΛ and Λα potentials. A phenomenological dispersive three-body force, V
Λαα, consistent with the B
Λ of Λ9Be in the Λαα model underbinds ΛΛ10Be. The incremental ΔB
ΛΛ values for the s- and p-shell cannot be reconciled, consistent with the finding of earlier analyses.
相似文献
993.
Suhana Arshad Dian Alwani Zainuri Nuridayanti Che Khalib Kaliyaperumal Thanigaimani Mohd Mustaqim Rosli 《Molecular Crystals and Liquid Crystals》2018,664(1):218-240
The new chalcone compound namely (E)-1-(4-Bromophenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one (C18H17BrO4) is crystallized in the monoclinic crystal system of P21/c space group. The unit cell dimensions are: a = 8.0753 (10) Å, b = 21.873 (3) Å, c = 9.3362 (12) Å, α = 90°, β = 99.369 (2), γ = 90° and Z = 4. The single crystal was grown using slow evaporation solution growth technique. The newly synthesized compound was characterized by using IR, 1H- and 13C-NMR, UV-Vis and single crystal X-ray diffraction analyses. Quantum chemical method of Density Functional Theory (DFT) with B3LYP/6-311++G(d,p) has been employed to study the structural and spectral properties of the compound. The electronic absorption spectrum was calculated using the time dependent functional theory (TDDFT) method. The most stable conformer of the title chalcone is identified from the computational results. Hirshfeld surface analysis with fingerprint plots has been used as a graphical tool for visualization and understanding of intermolecular interactions. Intermolecular C?H····O interaction observed stabilize the crystal structure, forming an infinite one dimensional column. The effect of this intermolecular interaction in the solid state can be seen in the difference between the experimental and the theoretically optimized geometrical parameters. The crystal is transparent in the entire visible region and absorptive in the UV region. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron potential (MEP). The other molecular properties like charge transfer are explain using Mulliken population analysis. The antioxidant test indicated that the 2,3,4-trimethoxy substitution on the bromide chalcone to be one of the favorable modification to enhance its metal chelating activity. 相似文献
994.
Summary The three title compounds were prepared and their X-ray crystal stuctures were determined. All three compounds were found to contain extensive hydrogen bonding. 相似文献
995.
Chemical Composition and Acetylcholinesterase Activity of the Essential Oil of Anisophyllea disticha
Salleh Wan Mohd Nuzul Hakimi Wan Khamis Shamsul Rahman Muhammad Nurakmal Abdul Nafiah Mohd Azlan 《Chemistry of Natural Compounds》2021,57(2):371-373
Chemistry of Natural Compounds - 相似文献
996.
Aziman Eli Syafiqah Ismail Aznan Fazli Jubri Siti Fatimah Rahmat Muhammad Abdullah Idris Wan Mohd Razi 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):667-683
Journal of Radioanalytical and Nuclear Chemistry - Comprehensive radiological survey and evaluation of heavy metal contamination were conducted in Chini Lake, which has been awarded a pristine... 相似文献
997.
Mohd Yusoff SF Gilroy JB Cambridge G Winnik MA Manners I 《Journal of the American Chemical Society》2011,133(29):11220-11230
Cylindrical block copolymer micelles with a crystalline poly(ferrocenyldimethylsilane) (PFDMS) core and a long corona-forming block are known to elongate through an epitaxial growth mechanism on addition of further PFDMS block copolymer unimers. We now report that addition of the semicrystalline homopolymer PFDMS(28) to monodisperse short (ca. 200 nm), cylindrical seed micelles of PFDMS block copolymers results in the formation of aggregated structures by end-to-end coupling to form micelle networks. The resulting aggregates were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). In some cases, a core-thickening effect was also observed where the added homopolymer appeared to deposit and crystallize at the core-corona interface, which resulted in an increase of the width of the micelles within the networks. No evidence for aggregation was detected when the amorphous homopolymer poly(ferrocenylethylmethylsilane) (PFEMS(25)) was added to the cylindrical seed micelles whereas similar behavior to PFDMS(28) was noted for semicrystalline polyferrocenyldimethylgermane (PFDMG(30)). This suggested that the crystallinity of the added homopolymer is critical for subsequent end-to-end coupling and network formation to occur. We also explored the tendency of the cylindrical seed micelles to form aggregates by the addition of PI-b-PFDMS (PI = polyisoprene) block copolymers (block ratios 6:1, 3.8:1, 2:1, or 1:1), and striking differences were noted. The results ranged from typical micelle elongation, as reported in previous work, at high corona to core-forming block ratios (PI-b-PFDMS; 6:1) to predominantly end-to-end coupling at lower ratios (PI-b-PFDMS; 2:1, 1:1) to form long, essentially linear structures. The latter process, especially for the 2:1 block copolymer, led to much more controlled aggregate formation compared with that observed on addition of homopolymers. 相似文献
998.
Padikkaparambil Silija Zahira Yaakob Mohd A. Yarmo Sankaran Sugunan Narayanan N. Binitha 《Journal of Sol-Gel Science and Technology》2011,59(2):252-259
The photocatalytic activity of carbon and nitrogen co-doped sol gel TiO2 is tested using methyleneblue degradation and it is found that the activity drops sharply with increase in calcination temperature.
The system calcined at 300 °C was found to be the most efficient in dye degradation and can be considered as a good candidate
for the future photocatalytic applications. This highly active anion doped TiO2 is found to show amorphous nature. Elemental analysis reveals the co existence of C and N dopants, which may be responsible
for the high efficiency of the catalyst. Visible absorbance is evident from the UV–VIS Diffuse Reflectance Spectra. The N2 adsorption desorption studies show the H1 hysteresis loops and a well defined mesoporous nature is observed for the catalytic
systems prepared in the presence of urea. XPS analysis indicates the presence of Ti–C and Ti–N bonds which are responsible
for the visible light activity of the photocatalysts. 相似文献
999.
A factorial split plot 4 × 3 experiment was designed to examine and characterize the relationship among production of secondary metabolites (total phenolics, TP; total flavonoids, TF), carbohydrate content and photosynthesis of three varieties of the Malaysian medicinal herb Labisia pumila Benth. namely the varieties alata, pumila and lanceolata under CO(2) enrichment (1,200 μmol mol(-1)) combined with four levels of nitrogen fertilization (0, 90, 180 and 270 kg N ha(-1)). No varietal differences were observed, however, as the levels of nitrogen increased from 0 to 270 kg N ha(-1), the production of TP and TF decreased in the order leaves>roots>stems. The production of TP and TF was related to increased total non structural carbohydrate (TNC), where the increase in starch content was larger than that in sugar concentration. Nevertheless, the regression analysis exhibited a higher influence of soluble sugar concentration (r(2) = 0.88) than starch on TP and TF biosynthesis. Photosynthesis, on the other hand, displayed a significant negative relationship with TP and TF production (r(2) = -0.87). A decrease in photosynthetic rate with increasing secondary metabolites might be due to an increase in the shikimic acid pathway that results in enhanced production of TP and TF. Chlorophyll content exhibited very significant negative relationships with total soluble sugar, starch and total non structural carbohydrate. 相似文献
1000.
Syam S Abdul AB Sukari MA Mohan S Abdelwahab SI Wah TS 《Molecules (Basel, Switzerland)》2011,16(8):7155-7170
Murraya koenigii is an edible herb widely used in folk medicine. Here we report that girinimbine, a carbazole alkaloid isolated from this plant, inhibited the growth and induced apoptosis in human hepatocellular carcinoma, HepG2 cells. The MTT and LDH assay results showed that girinimbine decreased cell viability and increased cytotoxicity in a dose-and time-dependent manner selectively. Girinimbine-treated HepG2 cells showed typical morphological features of apoptosis, as observed from normal inverted microscopy and Hoechst 33342 assay. Furthermore, girinimbine treatment resulted in DNA fragmentation and elevated levels of caspase-3 in HepG2 cells. Girinimbine treatment also displayed a time-dependent accumulation of the Sub-G(0)/G(1) peak (hypodiploid) and caused G(0)/G(1)-phase arrest. Together, these results demonstrated for the first time that girinimbine could effectively induce programmed cell death in HepG2 cells and suggests the importance of conducting further investigations in preclinical human hepatocellular carcinoma models, especially on in vivo efficacy, to promote girinimbine for use as an anticancer agent against hepatocellular carcinoma. 相似文献