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81.
Physics of Atomic Nuclei - Based on the behavior of elastic scattering of proton and anti-proton at $$\sqrt{s}=1.96$$ TeV for squared four-momentum transfer $$0.26<{-}t<1.2($$ GeV... 相似文献
82.
The synthesis and characterization of two new aluminate(Ⅲ) complexes with general formula K[AlCl3X] are reported. These compounds derived from aluminate trichloride and related salts. Potassium trichlorothiocyanoaluminate, PCTA, and potassium trichlorocyanatoalu-minate, PCCA, are two new ionic aluminate complexes. They can be easily synthesized in a nearly quantitative yield by using the direct reaction of AlCl3 and KX. The complexes were characterized by physico-chemical and spectroscopic methods. Theoretical calculations have been used for the extraction of structural and spectroscopic data of these new synthesized complexes. The antibacterial activities of such compounds were studied against the Staphylococcus aureus, Escherichia coli, Staphylococcus Epidermidis, Estreptococo B and Shigella. 相似文献
83.
An efficient and simple synthesis of α‐hydroxyphosphonates via reaction of aldehydes and ketones with dimethylphosphite in the presence of MgCl2/Et3N base system is reported. The use of readily available and easy to handle reagent MgCl2/Et3N makes this method simple, convenient, and practical. 相似文献
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86.
Zahra Moulana Mousa Ghaemi Soudabeh Qasemi Khadijeh Ghassemi Mohammad R. Hasanjani Roushan 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(1):30-39
There are many different strategies to decrease the incidence of infection of medical device and food related containers. One way to prevent infection is by modifying the polymers used in making the devices and containers. Incorporation of antimicrobial agents in the bulk material or in formulations of medical devices production has been considered a viable alternative for systemic application of antibiotics. In this article, preparation of a series of triazole containing polymers, poly(triazole-amide-imide)s (PTAI)s and poly(triazole-amide) (PTA)s, and their monomers are reported. These polymers were readily soluble in a variety of organic solvents, showed significant thermal properties and also viscosities in the range of 0.55–0.66 dL/g. They have been tested against a range of Gram-positive and Gram-negative pathogens. The results indicated that these novel polymers containing triazole moiety in their repeating units can effectively control Gram-positive and negative pathogens and their physic-chemical properties besides their antibacterial characteristics make them unique candidate for using in the manufacturing of the medical devices. 相似文献
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A mild and highly chemoselective method for the preparation of oxathiolane from aliphatic and aromatic aldehydes and ketones with 2-mercaptoethanol in the presence of catalytic amount of N-bromosaccharin at room temperature is reported. 相似文献
89.
A metal-dielectric mirror is shown as a simple solution for high-reflectivity coatings on cleaved-facet edge-emitting lasers, as well as a means to provide wavelength stabilization and spectral filtering. We show, through the use of a simple SiO2/Ti/Au coating, reflectivities better than 90% and a 25% reduction in the 30-dB linewidth of the output spectrum. Wavelength filtering and varying reflectivities are described as the result of multiple reflections and a coupled-cavity effect. 相似文献
90.
Sara Sobhani Zahra Pakdin Parizi Soodabeh Rezazadeh 《Journal of organometallic chemistry》2011,696(3):813-817
3-Aminopropylated silica gel, which is prepared from commercially available and cheap starting materials, is introduced as an efficient and recyclable catalyst for the phospha-Michael addition of phosphorus nucleophiles to α,β-unsaturated malonates. Short reaction times, mild reaction conditions, ease of recovery and catalyst reusability make this method a new, economic and waste-free chemical process for the synthesis of β-phosphonomalonates. 相似文献