A solid-phase extraction (SPE) method for sample clean-up and preconcentration followed by reversed-phase high-performance liquid chromatography (RP-HPLC) with uv detection is reported for determination of polycyclic aromatic hydrocarbons (PAHs) in the caspian seawater. A good resolution was obtained using acetonitrile:water (40:60) as mobile-phase for separation of these compounds. The eff...

The aim of this work was to find a relationship between electroosmotic flow (EOF) velocity of the mobile phase in pressurized planar electrochromatography (PPEC) and physicochemical properties like zeta potential, dielectric constant, and viscosity of the mobile phase as well as its composition. The study included different types of organic modifiers (acetonitrile, methanol, ethanol, acetone, f...

easily degradating and various isomeric forms of rapamycin (sirolimus) face the determination of this compound to many challenges. in this study, we developed and validated the isocratic reversed phase high performance liquid chromatographic (rp-hplc) method for rapamycin. separation was performed on a c8 column (mz, 15 × 4.6 mm, 5 µm particle size) using methanol:water (80:20 v/v) as the mobil...

in published high performance liquid chromatographic (hplc) methods for analysis of topiramate (tpm) in pharmaceutical dosage forms and raw materials refractive index detector (rid) has been used which is not available in many laboratories and has low sensitivity. we described a new, sensitive and simple hplc method for determination of topiramate in pharmaceutical forms and in-virto dissolutio...

there is a great interest in developing rapid analytical methods and provide appropriate parametersfor quantitative analysis of compounds derived from refractory pollutants. such methods are important forroutine quality control analysis of an effluent before being discharged into the environment. therefore, a rapid methodology for identification and quantification of some aliphatic acids is pro...

Conventional distributed and domino effect-free failure recovery techniques are inappropriate for mobile computing systems because each mobile host is forced to take a new checkpoint (based on coordinated checkpointing). Otherwise, multiple local checkpoints may need to be stored in stable storage (based on communication-induced checkpointing). Hence, this investigation presents a novel domino ...

Bootstrap percolation is a general representation of some networked activation process, which has found applications in explaining many important social phenomena, such as the propagation of information. Inspired by some recent findings on spatial structure of online social networks, here we study bootstrap percolation on undirected spatial networks, with the probability density function of lon...

in this study, caffeic acid (ca) and its three derivatives including 3-caffeoylquinic acid (3-cqa, neochlorogenic acid), 4-caffeoylquinic acid (4-cqa, cryptochlorogenic acid), and 5-caffeoylquinic acid (5-cqa, chlorogenic acid) were identified in bupleurum chinense aerial parts using reverse-phase high-performance liquid chromatography (rp-hplc) with photodiode array (pda) detector, reference c...

two modified methods for assaying sodium diclofenac were developed by gc and hplc. diclofenac was converted into methyl ester derivative by methyl iodide in acetone. the ester was extract and subjected to glc with flame ionization detector. %5 se-30/chrom w-hp (80-100 mesh) was used as a column in gc. for reversed phase hplc, the mobile phase was methanol and water (55-45). the separation was p...