全文获取类型
收费全文 | 94篇 |
免费 | 3篇 |
专业分类
化学 | 87篇 |
晶体学 | 6篇 |
物理学 | 4篇 |
出版年
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 17篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 7篇 |
2007年 | 2篇 |
2006年 | 5篇 |
2005年 | 6篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1958年 | 3篇 |
排序方式: 共有97条查询结果,搜索用时 15 毫秒
21.
A novel protocol for the generation of β-branched Baylis-Hillman adducts in moderate yields (52-68%) as E/Z mixtures from commercially available dienoates such as ethyl sorbate and aryl aldehydes catalyzed by DABCO in DMSO is reported. 相似文献
22.
B. Sunil Kumar P. S. Kumar N. Srinivasulu B. Rajitha Y. Thirupathi Reddy P. Narsimha Reddy R. H. Udupi 《Chemistry of Heterocyclic Compounds》2006,42(2):172-175
Good yields of substituted coumarins were obtained by a synthetic method involving the Pechmann reaction using vanadium(III)chloride
(VCl3) reagent to effect this condensation under solvent-free conditions.
Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 197–200, February, 2006. 相似文献
23.
Reguri Buchireddy Khagga Mukkanti Polisetty Srinivasulu Koduri S. V. Srinivas 《Chromatographia》2008,67(3-4):275-280
We present a simple and reliable method for simultaneous determination of voriconazole and its main metabolite resulting from N-oxidation (UK-121,265), in human plasma. The work-up procedure used acetonitrile and potassium salts to precipitate plasma proteins. No internal standard was used. The chromatographic system used a LiChroCART® 250-4 cartridge packed with LiChrospher® 100 RP-8 (diameter particules, 5 μm). The UV monochromatic detector was set on 260 nm. The mobile phase consisted of a 60/40 (v/v) mixture of acetonitrile and water. The flow rate was 1 mL min?1. The retention times for voriconazole and its metabolite were 8.98 and 4.02 min respectively, and total run time was 12 min. The linearity of the method was investigated from 0.31 to 10.0 mg L?1; the lowest limit of quantification was 0.30 mg L?1. Precision ranged from 2.41% to 6.32% for voriconazole and 0.80% to 11.6% for the N-oxide voriconazole metabolite. Accuracy was between 93.0% and 101% for voriconazole and 90.0% and 101% for the N-oxide voriconazole metabolite. This rapid and accurate method could be interesting to investigate metabolite/voriconazole ratio with respect to CYP2C19 genetic status and CYP3A4 activity changes. 相似文献
24.
25.
Mallipattu Sreedhar Tukiakula Madhusudana Reddy Kami Reddy Sirisha Srinivasulu Reddy Jayarama Reddy 《Analytical sciences》2003,19(4):511-516
A sensitive adsorptive stripping voltammetric method for the determination of dinitrophenolic herbicides, dinoseb (DSB) and dinoterb (DTB) at a bare carbon paste electrode (CPE) and a clay modified carbon paste electrode (CMCPE) was developed. A systematic study of various experimental conditions, such as the pH, accumulation variables and composition of a modifier on the adsorptive stripping response, were examined by using differential pulse voltammetry. A significant improvement was observed in the sensitivity by using the present method with CMCPE. When CMCPE was used, a linear response was obtained over the concentration range 2 x 10(-10) to 3 x 10(-7) M and 6 x 10(-10) to 6 x 10(-7) M with lower detection limits of 1 x 10(-10) M and 5.4 x 10(-10) M for dinoseb and dinoterb, respectively, at an accumulation time of 100 s. The interference from other herbicides and ions on the stripping signals of both compounds was also evaluated. The described method was applied to estimate of the dinoseb and dinoterb in environmental samples. 相似文献
26.
1, 2, 3, 4-Cyclopentanetetracarboxylic acid (CPTA) may be used for the gravimetric determination of zirconium. The procedure is simple and relatively free from interference. 相似文献
27.
Veera Reddy Arava Srinivasulu Reddy Amasa Bharat Kumar Goud Bhatthula Laxmi Srinivas Kompella Venkata Prasad Matta M. C. S. Subha 《合成通讯》2013,43(21):2892-2897
An efficient and enantioselective hydrogenation of N-acetylamino phenyl acrylic acids was successfully developed by using ruthenium catalyst. This methodology is important in the field of pharmaceuticals and provides a new process for the preparation of unnatural amino acids and tamsulosin chiral intermediate. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.] 相似文献
28.
B. Sridevi P. V. Chalapathi M. Srinivasulu V. G. K. M. Pisipati D. M. Potukuchi Corresponding author 《Liquid crystals》2013,40(3):303-310
The synthesis and characterization of five hydrogen-bonded ferroelectric liquid crystal complexes (HBFLCs) prepared from mesogenic p-n-alkoxy benzoic acids and non-mesogenic propionic/butyric acids with different chiral centres are reported. Complementary intermolecular hydrogen bonding is confirmed through IR study. HBFLCs are found to exhibit chiral nematic (N*), smectic C* (SmC*) and smectic G* (monotropic) phases in their cooling profiles during polarizing thermal microscopy and differential scanning calorimetry. Phase coexistence regions are observed above the IN* transition. The chiral nematic to smectic C* transition is found to be of first order. The temperature variation of spontaneous polarization exhibited by these HBFLC complexes in their SmC* phase is presented. The effect of non-covalent interaction imparted by the soft hydrogen bonding in these LC complexes on enhanced or induced thermal stability of tilted LC phases is discussed. 相似文献
29.
D. Rajasekhar D. Subba Rao D. Srinivasulu C. Naga Raju M. Balaji 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1017-1025
Abstract An efficient and high-yield synthesis of a class of new α-aminophosphonate derivatives as diethyl α-aryl/2-thienyl-α-[2-(phenylthio)phenylamino]methylphosphonates 6a–j in short reaction times from three component coupling reactions (Kabachnik-Fields reaction) of 2-aminodiphenylsulfide 3, substituted phenyl/heterocyclic aldehydes 4a–j, and diethyl phosphite 5 is reported. The reaction proceeds smoothly in the presence of the catalyst, nano-silica-supported boron trifluoride (BF3·SiO2) without using solvent under microwave irradiation. The title compounds were tested for in vitro antibacterial and antifungal activities at concentrations of 100 and 200 μg/disc. Minimum inhibitory concentrations (MICs) were also examined. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional text, figures and tables. 相似文献
30.