全文获取类型
收费全文 | 117篇 |
免费 | 3篇 |
专业分类
化学 | 88篇 |
力学 | 3篇 |
数学 | 2篇 |
物理学 | 22篇 |
无线电 | 5篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 9篇 |
2018年 | 5篇 |
2017年 | 14篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 13篇 |
2012年 | 6篇 |
2011年 | 3篇 |
2010年 | 6篇 |
2009年 | 1篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1989年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有120条查询结果,搜索用时 10 毫秒
1.
Shaila Lalkuwar Bajoria Virendra Kisan Rathod N. K. Pandey U. Kamachi Mudali R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):271-276
Extraction power of solvent depends upon the physical properties of the system. Tri-n-butyl phosphate (TBP) in dodecane is a versatile solvent used in the nuclear fuel reprocessing like PUREX process. The study of physical properties like density, viscosity, interfacial tension and solubility for TBP–nitric acid–dodecane system will be helpful in carrying out different extraction studies during PUREX process. Thus, physical properties like density, viscosity, interfacial tension and solubility have been measured for TBP–nitric acid–dodecane system using pycnometer, viscometer, pendant drop method and high performance liquid chromatography respectively. It has been observed that density and viscosity increases but interfacial tension and solubility decreases with the concentration of TBP in dodecane–nitric acid system. Physical properties of 30 % TBP–nitric acid–dodecane system have also been studied in detail. All these studies will also be useful in stripping out dissolved TBP from the nuclear waste. 相似文献
2.
3.
A simple, rapid, and precise HPTLC method was developed for quantitative estimation of gallic acid in stem bark of Myrica esculenta, family Myricaceae. Separation was performed on silica gel 60F254 HPTLC plates using toluene-ethyl acetate-formic acid-methanol (3 + 3 + 0.6 + 0.4, v/v/v/v) mobile phase for separation of the extracted components. The determination was carried out in the UV densitometric absorbance-reflection mode at 280 nm. The amount of gallic acid in free and combined form in the stem bark powder was found to be 0.276 and 0.541%, respectively, on a dry weight basis. The method was validated in terms of linearity, accuracy, precision, and specificity according to International Conference on Harmonization guidelines. Gallic acid response was found to be linear over a broad concentration range of 0.4-2.0 microg/band. LOD and LOQ were 0.103 and 0.312 microg/spot, respectively. The developed method is capable of quantifying amounts of gallic acid in stem bark powder of M. esculenta. 相似文献
4.
Yadav M Rao R Kurani H Rathod J Patel R Singhal P Shrivastav PS 《Journal of chromatographic science》2010,48(10):811-818
A sensitive and high throughput ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS-MS) method has been developed for the determination of pramipexole, a dopamine agonist, in human plasma. Sample preparation involved liquid-liquid extraction of pramipexole and ranitidine as the internal standard (IS) in ethyl acetate from 100 μL human plasma. The chromatographic separation is achieved on a Waters Acquity UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm) analytical column using an isocratic mobile phase, consisting of 10 mM ammonium formate (pH 7.50)-acetonitrile (15:85, v/v), at a flow-rate of 0.5 mL/min. The precursor → product ion transition for pramipexole (m/z 212.1 → 153.0) and IS (m/z 315.0 → 176.1) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) and positive ion mode. The method was validated over a wide dynamic concentration range of 20-4020 pg/mL. Matrix effect is assessed by post-column infusion experiment and the process efficiency were 91.9% and 85.7% for pramipexole and IS, respectively. The method is rugged and rapid with a total run time of 1.5 min and is applied to a bioequivalence study of 0.25 mg PPX tablet formulation in 30 healthy Indian male subjects under fasting condition. 相似文献
5.
Patel Kalpana G. Patel Vandana G. Patel Kirti V. Gandhi Tejal R. 《平面色谱法杂志一现代薄层色谱法》2010,23(5):326-331
JPC – Journal of Planar Chromatography – Modern TLC - A simple, rapid, and precise high-performance thin-layer chromatographic method has been established for quantitative analysis of... 相似文献
6.
Grace‐Ann M. Lobo Sneha A. Chitre Spandan M. Rathod Robert B. Smith Ray Leslie Callum Livingstone James Davis 《Electroanalysis》2007,19(24):2523-2528
The exploitation of 2‐bromo‐1,4‐naphthoquinone (NQBr) as a selective redox label for the determination of reduced thiol functionalities (RSH) has been investigated. The system is selective for RSH functionality, giving distinct voltammetric signals for glutathione and cysteine but can also be adapted for broad spectrum thiol detection. Ion chromatographic protocols based on conductimetric detection enable total RSH analysis (protein and monomolecular moieties) within human plasma. Bromide released through the reaction can be easily quantified and integrated within normal IC measurements. The efficacy of the approach has been assessed and the response validated through comparison with the standard colorimetric technique. 相似文献
7.
Gabapentin is an anticonvulsant drug used for the treatment of epilepsy. It is not bound to plasma protein and is not metabolized. A high performance liquid chromatography–mass spectrometric micro method is described in this report for its determination from human plasma. Chromatography was performed on a 50 × 4.6 mm, 4 μm nitrile column and the parent ion detected in the positive ionization mode on single quadrupole analyzer (Q1MI) with atmospheric pressure ionization source. Extraction was carried out on C18, 100 mg/3cc cartridge using 10 μL sample volume. The mean extraction recovery was 97% and within batch and between batch coefficients of variation were <9%. Lack of interference from endogenous substances helped in achieving a highly sensitive method without the need for monitoring fragment ions. The lowest concentration injected on column for calibration curve was 195 pg (range 0.5–64 ng). The method was applied for analysis of samples from a cross-over bio-equivalence study comparing two formulations. 相似文献
8.
The unique advantages of quantum dot (QD) bioconjugates have motivated their application in biological assays. However, physical characterization of bioconjugated QDs after surface modification has often been overlooked. Here, biotinylated antibodies (biotin-IgG) were attached to commercial streptavidin-conjugated quantum dots (strep-QDs) at different stoichiometric ratios, and these QD bioconjugates were characterized with atomic force microscopy and discontinuous sodium dodecyl sulfate agarose gel electrophoresis (SDS-AGE). The results from these complementary analytical techniques showed that the molar ratio determined the relative sizes, molecular weights and morphologies of the QD bioconjugates. Additionally, the novel discontinuous SDS-AGE analysis confirmed specific binding between biotin-IgG and strep-QDs. Researchers who design QD bioconjugates for cell-based assays should consider stoichiometry-dependent differences in the physical properties of their QD bioconjugates. 相似文献
9.
Artabotrys odoratissimus inhibitory effect on mild steel (MS) corrosion in 0.5 M H2SO4 solution has been assessed utilizing mass loss, electrochemical potentiodynamic polarization, and impedance spectroscopy techniques. The Artabotrys odoratissimus plant has a wide range of bioactive compounds. Phytochemicals were tested for ethanolic Artabotrys odoratissimus leaves extract (AOLE) using the FeCl3 test, Salkowaski's test, and others. Corrosion tests were conducted at varying inhibitor concentrations and temperatures. The inhibitory impact of AOLE on corrosion of MS was reported to improve with increasing concentration. Polarization experiments revealed that AOLE is a mixed kind of inhibitor and the inhibition efficacy (ηw) for MS is 93.27% for 1.25 g/L AOLE. For Electrochemical impedance spectroscopy (EIS), maximal inhibitory efficacy (ηw) was 91.62% due to AOLE adsorption on the MS surface. The obtained results using each methodology are highly consistent and closely resemble each other. The adsorption of AOLE molecules on an MS surface from the bulk of the solution causes the inhibitor's inhibition action, and the adsorption mechanism follows Langmuir adsorption isotherm. The computed values ranged between ?32.919 and ?33.520 kJ mol?1, implying a spontaneous and exothermic inhibitory action. The thermodynamic and activation parameters are often used to understand corrosion inhibition mechanisms. The comparison of corrosion product and pure extract FT-IR spectrum indicates the nature of AOLE adsorption on the MS surface. The surface morphology of MS samples was assessed using atomic force microscopy (AFM), scanning electron microscope (SEM), and contact angle techniques. 相似文献
10.
Leena V. Bora Manan Rathod Kush Kapadia Sonal Thakkar R.N. Reddy Sandesh S. Chougule Nisha V. Bora 《印度化学会志》2022,99(7):100560
In this study, we report a waste material-ground granulated blast furnace slag (GGBFS) as a low cost geopolymer, hybridised with ZnO to form a novel and efficient photocatalyst capable of discolouring textile wastewater. GGBFS is a waste material in an iron industry. Methylene blue was used as the probe dye and natural sunlight was used for activation of the photocatalyst. It was observed that under the experimental conditions, ZnGP-40 exhibited twice the discoloration efficiency than conventionally used ZnO or TiO2. This enhanced performance is majorly attributed to increased surface area of ZnO when strewn in the GGBFS matrix. The photocatalysts were characterized by SEM, TEM, PSA, TGA, BET and UV–Vis/NIR. The effect of photocatalyst loading, speed of agitation and solar insolation has also been studied. Since this study has been performed in direct sunlight, it exhibits a realizable application of solar energy in the treatment of wastewater. 相似文献