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161.
162.
The possible existence of 16 parameter sets for strongly regular graphs with 100 or less vertices is still unknown. In this paper, we outline a method to search for strongly regular graphs by assuming a non-trivial automorphism of prime order. Among these unknown parameter sets, we eliminated many possible automorphisms, but some small prime orders still remain. We also found 6 new strongly regular graphs with parameters (49,18,7,6). 相似文献
163.
Robabeh Baharfar Mohammad Javad Taghizadeh Majid Ahmadian Seyed Meysam Baghbanian 《中国化学快报》2010,21(2):175-178
<正>The addition of 2,4-dihydroxyaceto(and benzo)phenone to propiolic ester is catalyzed by triphenylphosphine or tert-butyl isocyanide to form O-vinyl aryl derivatives in fairly good yields. 相似文献
164.
Alcohols and phenols were efficiently acylated with acetic anhydride in the presence of vanadyl sulfate (VOSO4.3H2O) at room temperature in high yields. 相似文献
165.
Palladium nanoparticles immobilized on sepiolite–cyclodextrin nanosponge hybrid: Efficient heterogeneous catalyst for ligand‐ and copper‐free C─C coupling reactions 下载免费PDF全文
A novel hybrid system composed of sepiolite clay and cyclodextrin nanosponge (CDNS) was prepared via reaction of Cl‐functionalized sepiolite with amine‐functionalized CDNS. CDNS–sepiolite was then applied for immobilization of Pd(0) nanoparticles. The resulting hybrid system, Pd@CDNS‐sepiolite, was characterized using various techniques and successfully used as an efficient and heterogeneous catalyst for ligand‐ and copper‐free Sonogashira and Heck coupling reactions under mild reaction conditions. Recycling experiments confirmed that Pd@CDNS‐sepiolite was recyclable and could be used for several consecutive reaction runs with slight Pd leaching and loss of catalytic activity. 相似文献
166.
Influences of Different Enzymatic Treatment on Denim Garment 总被引:1,自引:0,他引:1
In current study, the effects of different enzymatic treatment including acid cellulases, neutral cellulases, and combination
of laccases with cellulases on denim garment were investigated. The color changes of different samples were compared by colorimetric
indices for the garment surface and back and also white pocket. Abrasion resistance, tensile strength, and crease recovery
angle of the samples were measured within the standard methods. Also, surfaces of the treated samples were observed by SEM.
The results showed that the combination of laccases with cellulases help to improve the lightness and decrease staining on
both back of garment and on white pocket. 相似文献
167.
168.
Heravi Majid M. Bakhtiari Khadijeh Alinejhad Hamideh Saeedi Mina Malakooti Reihane 《中国化学》2010,28(2):269-272
β‐Aminoalcohols were synthesized in high yields by reaction of epoxides with amines in the presence of MCM‐41 as a green and reusable catalyst under solvent‐free conditions. 相似文献
169.
Condensation of aldehydes, isonitriles and 2‐aminopyridines in the presence of H3PMo12O40 affords different derivatives of 3‐aminoimidazo[1,2‐a]pyridine in good to excellent yields. 相似文献
170.
3,4,6‐Trisubstituted 2‐pyridone derivatives have been synthesized in good to excellent yields through a condensation reaction of various 1,3‐diketones with amides in the presence of 1,4‐Diaza‐bicyclo[2,2,2]octane (DABCO) at reflux temperature. 相似文献