The 1:1 structural order and B-site cation order in Pb(Mg1/3Nb2/3)O3 ceramics was significantly enhanced by Zr4+ substituting Nb5+ according to the chemical formula Pb(Mg1/ 3Zr2x/3Nb2(1−x)/3)O3−x/3. The enhanced structural and cation order was revealed by both X-ray diffraction and transmission electron microscopy. The increased charge difference and the introduced oxygen vacancies were suggest...

This paper presents a mathematical model for performing availability and reliability analysis of a parallel repairable system consisting of n identical components with degradation facility and common-cause failures. In addition, system repair time is assumed to be arbitrarily distributed. Markov and supplementary variable techniques are used to develop equations for the model. As an illustratio...

Magnesium ions (Mg2+) are divalent cations essential for various cellular functions. Mg2+ homeostasis is maintained through Mg2+ channels such as MgtE, a prokaryotic Mg2+ channel whose gating is regulated by intracellular Mg2+ levels. Our previous crystal structure of MgtE in the Mg2+-bound, closed state revealed the existence of seven crystallographically-independent Mg2+-binding sites, Mg1-Mg...

Saliva contains mucins, which protect epithelial cells. We showed a smaller amount of salivary mucin, both MG1 and MG2, in the premenopausal female smokers than in their nonsmoking counterparts. Smokers' MG1, which contains almost 2% cysteine/half cystine in its amino acid residues, turned out to be chemically altered in the nonsmoker's saliva. The smaller acidic glycoprotein bands were detecta...

This paper provides steady state queue-size distribution for a G/G/1 queue by using principle of maximum entropy. For this purpose we have used average queue length and normalizing condition as constraints to derive queue-size distribution. Our results give good approximation as demonstrated by taking a numerical illustration. In particular case when square coefficient of variation of inter-arr...

in this paper, we study the network location problem for two congestible facilities, considering impatient customers. we suppose that when a customer arrives his/her corresponding facility and faces a queue with the size more than a predetermined threshold, the customer decides not to join the queue but to go to the closest facility to current facility. in the second facility, if the queue size...

a single server queue with bernoulli vacation has been considered. in addition the admission to queue is based on a bernoulli process and the server gives two type of services. for this model the probability generating function for the number of customers in the queue at different server's state are obtained using supplementary variable technique. some performance measures are calculated. ...