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Heterocyclic synthesis using nitrilimines: part 14. Synthesis of new pyrazole derivatives
Nitrilimines 1,3-dipolar cycloaddition phthalides pyrazoles
2010/10/18
A new series of 1,3,4,5-tetrasubstituted pyrazoles have been synthesized by the 1,3-dipolar cycloaddition of suitable nitrilimines to 3-propylidene and 3-benzylidene-phthalide. Both analytical and spe...
Synthesis and antimicrobial activities of some new biheterocyclic compounds containing 1,2,4-triazol-3-one and 1,3,4-thiadiazole moieties
1,2,4-triazol-3-one 5-thioxo-1,2,4-triazole
2010/10/18
2-(4-Amino-3-(4-chlorophenyl)-5-oxo-4,5--dihydro-1H-1,2,4-triazol- 1-yl)-N'-[(2,6-dihalogenophenyl)-methylene]acetohydrazides (3a,b) was obtained via the formation of 2-(4-amino-3-(4-chlorophenyl)-5-o...
Synthesis and characterization of gold nanoparticles supported on zinc oxide via the deposition-precipitation method
Au nanoparticles ZnO nanorods deposition-precipitation
2010/10/19
Gold nanoparticles supported on zinc oxide nanoparticles were synthesized at several pH levels via the deposition-precipitation (DP) method. The effects of pH on gold loading, particle size, and parti...
A calorimetric study of the interaction of silver ions with jack bean urease
Urease silver ion isothermal titration calorimetry
2010/10/19
A thermodynamic study of silver ions by jack bean urease (JBU) was carried out at 2 temperatures, 27 and 37 °C, in Tris buffer (30 mM; pH 7.0) using isothermal titration calorimetry (ITC). There was a...
Friedel-Crafts acylation of arenes with carboxylic acids using silica gel supported AlCl3
Acylation aluminium trichloride ketones silica gel
2010/10/19
Aromatic compounds react smoothly with carboxylic acids in the presence of silica gel supported aluminium trichloride to afford the corresponding ketones with high regioselectivity in high to excellen...
Sulfonic acid-functionalized silica: a remarkably efficient heterogeneous reusable catalyst for the one-pot synthesis of 1,4-dihydropyridines
1,4-Dihydropyridine b-dicarbonyl compounds solid acid SiO2-R-SO3H
2010/10/19
An efficient one-pot method for the synthesis of 1,4-dihydropyridines from b-dicarbonyl compounds, aldehyde, and ammonium acetate is reported using sulfonic acid-functionalized silica at 90 °C under s...
Synthesis and characterisation of vanadium(III) complexes of biphenylphenols
Vanadium(III) complexes biphenylphenols magnetic study
2010/10/19
The vanadium(III) complexes of composition [VCl3-n(OAr1,2)n.(THF)2] (OAr1 = 2-phenylphenoxo and OAr2 = 4-phenylphenoxo, THF = tetrahydrofuran; n = 1 /to 3) were prepared by in situ reaction of VCl3.(T...
Preparation of polystyrene/montmorillonite nanocomposites: optimization by response surface methodology (RSM)
Montmorillonite organoclays polymer polystyrene
2010/10/19
Preparation of polystyrene (PS)-montmorillonite nanocomposites was carried out in 3 steps: purification and determination of the cation exchange capacity (CEC) of clay, synthesis of organoclay, and pr...
A new dinuclear lead(II) complex of 2,3-diphenyl-tetrazole-5-thione: synthesis and characterization
Lead complex tetrazole-5-thione crystal structure
2010/10/19
The present work reports on the synthesis, crystal structure, fluorescence, electrochemical behavior, and thermogravimetric analysis of a new dinuclear lead(II) complex of 2,3-diphenyl-tetrazole-5-thi...
Silica supported polyphosphoric acid (PPA-SiO2): an efficient and reusable heterogeneous catalyst for the one-pot synthesis of a -amino phosphonates
a -Amino phosphonates PPA-SiO2 heterogeneous catalyst
2010/10/19
An efficient green protocol is described for the preparation of a -amino phosphonates, employing a one-pot three-component condensation reaction between aldehydes, amines, and trialkyl phosphites in t...
Geochemistry and mineralogy of Paleocene-Eocene Oum El Khecheb phosphorites (Gafsa-Metlaoui Basin) Tunisia
phosphorites carbonate-fluorapatite REE trace elements Tunisia
2017/8/9
Upper Paleocene to Lower Eocene phosphates of the Jebel Oum El Khecheb profile (Gafsa-Metlaoui Basin GMB, Tunisia) are mostly composed of brown phospharenites lithified or not, granular, with pellets,...
Isotopic evidence of boron in precipitation originating from coal burning in Asian continent
boron isotopes coal burning trace elements Asian continent long-range transport
2017/8/9
The boron concentration and isotopic composition (δ11B) of precipitation collected from December 2002 to March 2006 at three sites on the Japan Sea coast were measured. Those sites have been considera...
本试验的目的是为了强化后续人工湿地处理黑臭河水的效能.试验结果显示，新型软性填料槽对于CODCr ，NH3-N和TP的平均去除率分别为36.63%，29.41%和29.22%，均高于空白对照槽.扫描电镜分析表明，新型软性填料具有纤维状、比表面积大且易于挂膜的特点，可用于黑臭水体生态系统的修复，且可作为人工湿地技术一种很好的补充.
双胍基均四嗪硝基酚高氮盐的合成、热分解和感度
有机化学 双胍基均四嗪硝基酚盐 有机合成 热分解 非等温反应动力学 感度性质
2014/3/4
双胍基均四嗪（DGTz）分别与三硝基苯酚（PA）、三硝基间苯二酚（TNR）和三硝基均苯三酚（TNPG）反应，制备出相应的3,6-双胍基-1,2,4,5-四嗪三硝基苯酚盐、3,6-双胍基-1,2,4,5-四嗪三硝基间苯二酚盐和3,6-双胍基-1,2,4,5-四嗪三硝基均苯三酚盐；用DSC和TG-DTG对其热分解机理进行了研究。结果表明，在10℃/min线性升温速率下3种盐在50~450℃均只有一个放...
Magnitudes and controls of organic and inorganic carbon flux through a chain of hard-water lakes on the northern Great Plains
Magnitudes and controls of organic inorganic carbon flux through hard-water lakes northern Great Plains
2014/4/17
Whole-lake carbon (C) mass-balance budgets were constructed for a chain of six hard-water lakes to quantify the relative importance of organic carbon (OC) and inorganic carbon (IC) exchanges between a...