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781.
以柠檬酸钠为配位剂、NaBH4为还原剂,将Sn(Ⅱ)和Sb(Ⅲ)盐在水溶液中共还原制得Sn-SnSb合金。X射线衍射和扫描电镜的测试结果表明:所得合金为多相合金,颗粒大小约200 nm。将该合金粉和石墨按质量比4∶1经机械球磨形成Sn-SnSb/石墨复合材料,将其作为锂离子电池阳极材料进行电化学性能测试,结果表明,该复合材料可逆容量超过600 mAh·g-1,具有良好的循环性能,15次循环内的稳定比容量为461 mAh·g-1,而纯Sn-SnSb合金粉15次循环后充电比容量为337 mAh·g-1。 相似文献
782.
P. S. Sai Prasad Jong Wook Bae Ki-Won Jun Kyu-Wan Lee 《Catalysis Surveys from Asia》2008,12(3):170-183
Impregnated and co-precipitated, promoted and unpromoted, bulk and supported iron catalysts were prepared, characterized,
and subjected to hydrogenation of CO2 at various pressures (1–2 MPa) and temperatures (573–673 K). Potassium, as an important promoter, enhanced the CO2 uptake and selectivity towards olefins and long-chain hydrocarbons. Al2O3, when added as a structural promoter during co-precipitation, increased CO2 conversion as well as selectivity to C2+ hydrocarbons. Among V, Cr, Mn and Zn promoters, Zn offered the highest selectivity to C2–C4 alkenes. The different episodes involved in the transformation of the catalyst before it reached steady-state were identified,
on the co-precipitated catalyst. Using a biomass derived syngas (CO/CO2/H2), CO alone took part in hydrogenation. When enriched with H2, CO2 was also converted to hydrocarbons. The deactivation of impregnated Fe–K/Al2O3 catalyst was found to be due to carbon deposition, whereas that for the precipitated catalyst was due to increase in crystallinity
of iron species. The suitability of SiO2, TiO2, Al2O3, HY and ion exchanged NaY as supports was examined for obtaining high activity and selectivity towards light olefins and
C2+ hydrocarbons and found Al2O3 to be the best support. A comparative study with Co catalysts revealed the advantages of Fe catalysts for hydrocarbon production
by F–T synthesis. 相似文献
783.
784.
V. Sai Sudhir 《Tetrahedron》2010,66(6):1327-2694
This work reports the synthesis of a wide range of ferrocenyl-amino acids and other derivatives in excellent yield. Diverse amino acid containing azides were synthesized and ligated to ferrocene employing click reaction to access ferrocenyl amino acids. Chiral alcohols, esters, diols, amines containing azido group were tagged to ferrocene via click reaction to generate ferrocene derived chiral derivatives. A novel strategy for direct incorporation of ferrocene into a peptide and a new route to 1, 1′disubstituted ferrocene amino acid derivative are reported. 相似文献
785.
Yuqing Xu Jingzheng Zhang Jing Liu Sai Li Cheng Li Wen Wang 《Natural product research》2015,29(11):1078-1082
Luteolin is reported to have antioxidant and anti-inflammatory properties. In this study, we investigated the protective effect of luteolin against the renal damage induced by d-galactose (d-gal). The levels of creatinine (Cr) and urea nitrogen (BUN) were evaluated in plasma, kidney sections were stained with haematoxylin–eosin, followed by assessment of the antioxidant and anti-inflammatory activity. Furthermore, we also investigated the expression of the p38 mitogen-activated protein kinase (p38 MAPK) and its phosphorylated activation. The results of luteolin treatment showed that the renal damages were attenuated. Luteolin could significantly ameliorate d-gal-induced oxidative damage and suppress the inflammatory response. Moreover, the result also shows that luteolin could significantly inhibit the p38 MAPK phosphorylation in the kidneys from the model of d-gal-treated mice. Therefore, our research suggests that luteolin might be involved in the attenuated oxidative stress and inflammatory responses, hence the protective effects against d-gal-induced renal damage. 相似文献
786.
Development and validation of a HPLC‐PDA bioanalytical method for the simultaneous estimation of Aliskiren and Amlodipine in human plasma 下载免费PDF全文
Sai Sandeep Mannemala Janaki Sankarachari Krishnan Nagarajan 《Biomedical chromatography : BMC》2015,29(3):346-352
A simple, unique and selective HPLC‐PDA method was developed and validated for the simultaneous estimation of aliskiren (ALS) and amlodipine (AML) in human plasma. Extraction of the sample was accomplished by protein precipitation. Plasma proteins were precipitated by employing acetonitrile containing hydrochlorothiazide as internal standard. The compounds were analyzed by HPLC by using PDA detector on a Hibar C18 (250 × 4.6 mm) column with a mobile phase comprising acetonitrile and phosphate buffer (pH 4.2 and 25 mm ; 60:40 v/v) with a flow rate of 0.8 mL/min. Different sample pretreatment techniques were evaluated but protein precipitation was found to be satisfactory, offering good recovery values of 97.11–98.45% for ALS and 97.5–99.12% for AML. The within‐day precisions for ALS were 96.66, 99.16 and 99.41% at 90, 240 and 480 ng/mL, respectively, and for AML they were 97.27, 99.54 and 99.31% at 3.3, 8.8 and 17.6 ng/mL, respectively. The between‐day precisions for ALS were 96.66, 99.16 and 99.41% at 90, 240 and 480 ng/mL, respectively and the between‐day precisions for AML were 98.18, 99.20 and 99.40% at 3.3, 8.8 and 17.6 ng/mL, respectively. The limit of quantitation was 30 and 1.0 ng/mL for ALS and AML respectively. Different constituents of plasma proteins did not interfere with the absolute recovery of ALS and AML. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
787.
Gattu Venkateshwarlu Akarapu Premalatha Anuganti Chakradhar KamatalaChinna Rajanna PondicheryKuppuswamySai Prakash 《Helvetica chimica acta》2010,93(2):345-349
Iodination of certain aromatic amines and phenols are triggered by the oxidation of KI by peroxy compounds such as tert‐butyl hydroperoxide (tBuOOH) under liquid‐phase and solvent‐free conditions by grinding the reactants in a mortar with a pestle. The reactions afforded corresponding iodo derivatives in good yield with high regioselectivity (Table 1). 相似文献
788.
The anionic polymerization of N-vinylcarbazole(NVC) by using optically active anionic initiators such as the lithium salts of(S)-1-(9H-fluoren-2-yl)-4-isopropyl-4,5-dihydrooxazole((S)-1-FIDH) and(S)-2-(9H-fluoren-2-yl)-4-isopropyl-4,5-dihydrooxazole((S)-2-FIDH) and complexes of(-)-Sparteine with n-butylithium(n-Bu Li-(-)-Sp) or fluorenyl lithium(FILi-(-)-Sp) was achieved. The yield and specific rotation of poly(N-vinylcarbazole)s(poly(NVC)s) were considerably affected by the molar ratio of(S)-FIDH to NVC. The highest yield and specific rotation were obtained with Li-(S)-1-FIDH as an initiator, with a molar ratio of monomer and initiator [M]/[I] = 10/1. The effects of the chiral initiators, type of solvent and the polymerization temperature were investigated. The obtained optical activity of polymers was attributed to asymmetric induction of the chiral initiators. 相似文献
789.
790.