a nanocomposite membrane cu2+ ion-selective electrode has been constructed using a new compound ethyl 1,2,3,4-tetrahydro-4-(4-methoxyphenyl)-6-methyl-2-oxopyrimidine-5-carboxylat (etmoc) as a neutral ionophore. the electrode works properly. it responds to cu2+ ion with a sensitivity of 29.5 ± 0.2 mv/decade over the range 1.0 × 10−9 to 5.0 × 10−1m at ph 3.0-8.0. the limit of detection was 4.5 × ...

Brownian movement has a history of more than two centuries. Studies that appeared in the scientific archival literature in the period until 1920 are listed by Einstein [1]. Articles that were written until 1970 are presented in Refs. [2] and [3]. Three-dimensional Brownian motors are discussed in [4], and Brownian movement of E. coli in [5]. All these studies and articles are based on a variety...

The efficiency of a thermodynamic system is a key quantity on which its usefulness and wider application relies. This is especially true for a device that operates with marginal energy sources and close to ambient temperatures. Various definitions of efficiency are available, each of which reveals a certain performance characteristic of a device. Of these, some consider only the thermodynamic c...

Depending on the exact experimental conditions, the thermodynamic properties of physical systems can be related to one or more thermostatistical ensembles. Here, we survey the notion of thermodynamic temperature in different statistical ensembles, focusing in particular on subtleties that arise when ensembles become non-equivalent. The 'mother' of all ensembles, the microcanonical ensemble, use...

Thermodynamic folding algorithms and structure probing experiments are commonly used to determine the secondary structure of RNAs. Here we propose a formal framework to reconcile information from both prediction algorithms and probing experiments. The thermodynamic energy parameters are adjusted using 'pseudo-energies' to minimize the discrepancy between prediction and experiment. Our framework...

the objective of this study was to assess the adsorption potential of activated carbon (ac) asan adsorbent for the removal of murexide (mu) from aqueous solutions. the influence of variablesparameters including ph, amount of adsorbent, sieve size of adsorbent, temperature and contact timeon mu removal was studied. following optimization of variables, the relation between concentrations ofdye re...