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41.
The essential oils obtained by hydrodistillation of the rhizomes of Alpinia aquatica Rosc. syn. Alpinia melanocarpa and Alpinia malaccensis Roscoe were analysed by capillary gas chromatography and gas chromatography-mass spectrometry. Eighteen compounds, representing 98.4% of the essential oil were identified in A. aquatica rhizome oil, with β-sesquiphellandrene in 36.5% being the major constituent, while 20 compounds representing 99.7% of the rhizome oil of A. malaccensis were identified, among which methyl (E)-cinnamate (78.2%) was the major constituent.  相似文献   
42.
40Ar-emulsion interactions are studied, to investigate the question of anomalons, in twoG- 5 emulsion stacks. In about 4600 primary interactions, projectile fragments of Z≧2 for all generations have been followed until they interact or leave the stack. After careful estimation of charges of these fragments, variation of their mean free paths is studied as a function of distance from the preceding interaction. Generation effect,N h dependence and production angle effect are investigated. In addition multi-chain events are analysed separately. Our results do not show anomalons at the 6% level and are consistent with non-occurrence of anomalons. However, this experiment is not sensitive enough to rule out anomalons (with a mfp of the order of 2 to 3 cm) produced at about 1% (or less) level.  相似文献   
43.
缺失功能性p35基因的苜蓿尺蠖核形多角体病毒(AcNPV)突变体(vΔP35K/pol+)感染草地夜蛾细胞(Sf9和Sf21)[1]及海灰翅夜蛾细胞(SL2)[2]时,引起细胞凋亡,从而使病毒的感染流产.我们发现海灰翅夜蛾核形多角体病毒(SlNPV)...  相似文献   
44.
In the title compound, [Fe(C17H14P)2]2[Sb4Cl16]·C2H6O, the Fe atoms lie on inversion centres and the pairs of cyclopentadienyl rings are consequently in a fully staggered conformation. The centrosymmetric anionic clusters formed by [Sb4Cl16]4? are surrounded by the cations and are held together by weak C—H?Cl interactions. These formations stack along the a axis to form columns, and the columns are interconnected by another weak C—H?Cl interaction along the b axis.  相似文献   
45.
Under solvent-free reaction conditions and in the presence of solid LiClO4 a novel and mild protocol for the one-pot, three-component synthesis of primary α-amino phosphonates from an aldehyde, hexamethyldisilazane and a trialkyl phosphite is described giving high yields and having short reaction times. The same products are obtained in very low yields, when the three-component reaction is carried out under microwave irradiation and in the absence of solid LiClO4. Examples of some prepared 1-aryl-N,N′-bis(arylidene)methanediamines are also described.  相似文献   
46.
In this study, Bi2S3@BSA–Bio–MTX nanoparticles (NPs) were synthesized for the first time by bovine serum albumin (BSA)-mediated biomineralization (Bi2S3@BSA NPs) followed by covalent bonding of biotin (Bio) and methotrexate (MTX) on the surface of the Bi2S3@BSA NPs via carbodiimide chemistry. The synthesized NPs were globular and exhibited uniform morphology with a hydrodynamic diameter of 107.6 ± 6.81 nm (mean ± standard deviation) and zeta potential of −20.9 ± 2.18 mV. Drug release from Bi2S3@BSA–Bio–MTX NPs indicated an enzyme-dependent release pattern. The in vitro biocompatibility of NPs was confirmed by investigating their cytotoxicity against the HEK-293 cell line and hemolysis assay test, whereas the in vivo biocompatibility of the NPs was evaluated and confirmed by the lethal dose 50 (LD50) test. To evaluate the in vitro anticancer activity of the functionalized NPs and MTX, their cytotoxic effects was assessed against 4T1 cancer cells by 5-dimethylthiazol-z-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with and without X-ray radiation. Results showed that Bi2S3@BSA–Bio–MTX NPs have excellent anticancer activity, especially following X-ray radiation.  相似文献   
47.
To increase the profitability and sustainability of agricultural waste, a facile green approach was established to synthesize zinc oxide nanoparticles (ZnO NPs) using saffron leaf extract as a reducing and stabilizing agent. Structural characteristics of NPs were investigated by X-ray diffraction (XRD), Fourier-transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and UV–Visible (UV–Vis) spectroscopy. Characterization results revealed that ZnO NPs is highly crystalline with a hexagonal wurtzite structure and spherical particles with diameter less than 50 nm, as confirmed by XRD and FESEM techniques. UV–Vis absorption spectra depicted an absorption peak at 370 nm, which confirms the formation of ZnO NPs. FTIR spectral analysis confirmed the presence of functional groups and metal oxygen groups. The biological activities of ZnO NPs were also investigated. The antibacterial effect of ZnO NPs was investigated against selected food pathogens (Salmonella Typhimurium, Listeria monocytogenes, and Enterococcus faecalis). The study results prove that the green synthesized ZnO NPs show enhanced antibacterial activity against S. Typhimurium when compared with other strains. A dose-dependent free radical scavenging activity was observed for ZnO NPs in both 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and fluorescence recovery after photobleaching (FRAP) assays. The ZnO NPs were evaluated for their photocatalytic activity during the degradation of methylene blue (MB) dye in aqueous solutions. The maximum removal of MB achieved was 64% with an initial ZnO NP concentration of 12 mg/mL under UV light. The present study revealed that the agricultural waste (saffron leaf) provides a simple and eco-friendly option to sustainably synthesize ZnO NPs for use as a photocatalyst. In addition, this is the first report on saffron leaf-mediated synthesis of ZnO NPs.  相似文献   
48.
A highly efficient Fe3O4@VitB1–Ag(I) magnetic catalyst has been obtained using surface modification of Fe3O4. To this end, silver chloride was immobilized on Fe3O4 nanoparticles via vitamin B1 biomolecules. The synthesized biocompatible magnetic catalyst was applied in an A3-coupling reaction in the presence of aldehyde, amine and phenyl acetylene under solvent-free conditions and afforded the desired products in excellent yields. Also, interactions between metal and ligand in the Fe3O4@VitB1–Ag(I) were studied using theoretical calculations.  相似文献   
49.
Material designs that use donor and acceptor units are often found in organic optoelectronic devices. Molecular level insight into the interactions between donors and acceptors are crucial for understanding how such interactions can modify the optical properties of the organic optoelectronic materials. In this paper, tris(4-(tert-butyl)phenyl)amine (pTPA) was synthesized as a donor in order to compare with unmodified triphenylamine (TPA) in a donor–acceptor system by having 2,4,6-triphenyl-1,3,5-triazine (TRZ) as an acceptor. Dimerization of donors and acceptors occurred in solvent when the concentration of solute is high. At 0 K, using a polarizable continuum model, the nitrogen atom of TPA is found to stack on top of the center of triazine of TRZ, whereas such alignment is offset in pTPA and TRZ. We attributed such alignment in TPA-TRZ as the result of attractive interactions between partial localization of 2pz electrons at the nitrogen atom of TPA and the π deficiency of triazine in TPA-TRZ. By taking into account random motions of the solvent effect at 300 K in quantum molecular dynamics and classical molecular dynamics simulations to interpret the marked difference in emission spectra between TPA-TRZ and pTPA-TRZ, it was revealed that the attractive interaction between pTPA and TRZ in toluene is weaker than TPA and TRZ. Because of the weaker attractive interaction between pTPA and TRZ in toluene, the dimers adopted numerous ground state conformations resulting in broad emission bands superimposed with multiple small Gaussian peaks. This is in contrast to TPA-TRZ which has only one dominant dimer conformation. This study demonstrates that the strength of intermolecular interactions between donors and acceptors should be taken into consideration in designing supramolecular structures.  相似文献   
50.
A convenient and efficient solvent-free procedure is described for preparation of 6-amino-4-aryl-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles by four-component reaction of hydrazine hydrate, ethyl acetoacetate, aryl aldehyde, and malononitrile in the presence of a catalytic amount of titanium dioxide nano-sized particles. Short reaction times, high yields under ambient conditions, simple reaction, clean work-up, and reusability of the nano heterogeneous catalyst are the advantages of this method.  相似文献   
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