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In this work, we have been investigating an organic tandem solar cells composed of PF10TBT:PCBM by using optical modeling and simulation method to investigate the correlation between thickness and photocurrent. Possible thickness pairs of tandem cell are provided when front layer and back layer absorb same amount of photons. In order to obtain the possible thickness pairs for different wavelengths, photocurrent has been simulated as function of back and front layer thickness. Energy dissipation in term of distance along cell and wavelengths were analyzed to interpret the optimal geometry of tandem cell. In order to find the appropriate materials for maximum efficiency, energy dissipation as function of optical constant (n) and wavelengths were simulated to derive the optimal condition.  相似文献   
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Dextromethorphan is a probe substrate to determine CYP2D6 phenotype. The conversion of dextromethorphan to dextrorphan by CYP2D6 accounts for approximately 60% of total metabolism. Most analytical methods utilize complicated labor- and time-intensive sample processing methods with several liquid-liquid extraction (LLE) steps. Our goal was to develop a non-LLE based rapid and sensitive HPLC method, to measure dextromethorphan metabolism in human liver microsomes. A solid-phase filtration based reverse-phase HPLC method with fluorescence detection was developed and validated. Human liver (n = 6) microsomal incubations were carried out with dextromethorphan, under optimum conditions. The analytes were separated by one-step centrifugal filtration with Nanosep separation units. The filtrate was injected ( 50 microL) into a Waters Alliance 2690 HPLC system. Metabolic incubations were also conducted to determine levels using LLE for comparisons. The Nanosep separation step reduced the extraction time from 3h to 40 min. The limit of quantitation was 23.8 nM (9.7 ng/mL), recovery was approximately 98%, the mean precision values were <10% RSD for the controls (80, 320 and 640 nM) and mean percentage error was <5%. Michaelis-Menten parameters were determined to distinguish CYP2D6 phenotypes. A rapid and sensitive HPLC method is reported, which may be suitable for automation and allows phenotyping of human liver microsomes.  相似文献   
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An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using tungstate sulfuric acid as a catalyst was described.Mild conditions,good to excellent yields,easily available catalyst and easy work-up are the key features of this method.  相似文献   
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Here, task‐specific ionic liquid solid‐phase extraction is proposed for the first time. In this approach, a thiourea‐functionalized ionic liquid is immobilized on the solid sorbent, multiwalled carbon nanotubes. These modified nanotubes packed into a solid‐phase extraction column are used for the selective extraction and preconcentration of ultra‐trace amounts of lead(II) from aqueous samples prior to electrothermal atomic absorption spectroscopy determination. The thiourea functional groups act as chelating agents for lead ions retaining them and so, give the selectivity to the sorbent. Elution of the retained ions can be performed using an acidic thiourea solution. The effects of experimental parameters including pH of the aqueous solution, type and amount of eluent, and the flow rates of sample and eluent solutions on the separation efficiency are investigated. The linear dependence of absorbance of lead on its concentration in the initial solution is in the range of 0.5–40.0 ng/mL with the detection limit of 0.13 ng/mL (3sb/m, n = 10). The proposed method is applicable to the analysis of red lipstick, pine leaves, and water samples for their lead contents.  相似文献   
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Over the last decade, significant progress has been made towards the development of approaches that enable the capture of rare circulating tumor cells (CTCs) from the blood of cancer patients, a critical capability for noninvasive tumor profiling. These advances have leveraged new insights in materials chemistry and microfluidics and allowed the capture and enumeration of CTCs with unprecedented sensitivity. However, it has become increasingly clear that simply capturing and counting tumor cells launched into the bloodstream may not provide the information needed to advance our understanding of the biology of these rare cells, or to allow us to better exploit them in medicine. A variety of advances have now emerged demonstrating that more information can be extracted from CTCs with next‐generation devices and materials featuring tailored physical and chemical properties. In this Minireview, the last ten years of work in this area will be discussed, with an emphasis on the groundbreaking work of the last five years, during which the focus has moved beyond the simple capture of CTCs and gravitated towards approaches that enable in‐depth analysis.  相似文献   
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A Y chromosomal polymorphic markers screening strategy using a multiplex polymerase chain reaction (PCR) and DNA microchip electrophoresis technology has recently been developed. It is a part of the human Y chromosome haplotyping system for studying Japanese population genetics and its relationship with male spermatogenic failure. This strategy is based on optimizing and modifying the primer set concentrations while keeping all other components of the PCR mixtures and conditions similar to those of a singleplex PCR. Well-balanced PCR products are obtained without changing even the DNA oligomer melting temperatures. Here, a panel of primer sets are used to amplify two groups of Y chromosome markers. The first consists of five markers and the second consists of seven markers. Both are possibly deleted in infertile men. The microchip electrophoresis technology is fast and sensitive, enables direct molecular typing of several Y chromosomal markers, and is separated by a difference of as many as six base pairs.  相似文献   
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In this work, we aimed to improve the antibacterial activity of sulfamethoxazole (SMX) via its inclusion in a newly synthesized nanocomposite composed of CuFe2O4 nanoparticles and poly(vinyl alcohol)/silica‐based mesoporous materials. Characterization of this formulation using different techniques confirmed the correct synthesis and showed that this mesoporous nanocomposite had an amorphous structure with relatively high surface area of 1,620.7 m2 g?1 and mean pore diameter of 1.6576 nm. Zeta potential of the formulation was obtained to be zero which led to its higher bioavailability in comparison to pure SMX with negative zeta potential. Antibacterial property of the prepared formulation against Staphylococcus aureus and Escherichia coli was evaluated. Minimum inhibitory concentration of the SMX‐loaded mesoporous nanocomposite was considerably lower than those of pure SMX, indicating the efficient function of the mesoporous material as a delivery system. Kinetics of SMX release was also studied using zero‐order, first‐order, Higuchi, and Korsmeyer–Peppas kinetics models. According to the obtained results, the release kinetics was found to obey zero‐order model. So the possibility of sustained release of SMX from the synthesized carrier may be suggested.  相似文献   
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