PIM, PEM

High-temperature polymer-electrolyte membrane fuel cells (HT-PEM FC) are a very important type of fuel cell since they operate at 150-200 °C, allowing the use of hydrogen contaminated with CO. However, the need to improve stability and other properties of gas diffusion electrodes still hinders their distribution. Anodes based on a mat (self-supporting entire non-woven nanofiber material) of carbon nanofibers (CNF) were prepared by the electrospinning method from a polyacrylonitrile solution followed by thermal stabilization and pyrolysis of the mat...

BACKGROUND: Primary intraosseous meningiomas (PIMs) are rare, and PIMs of the vertebrae have not yet been reported. The authors report a case of primary meningioma arising from the vertebrae. OBSERVATIONS: A 49-year-old man presented with lower back pain and numbness in both lower extremities. Lumbar spine magnetic resonance imaging revealed an L2 pathological fracture with epidural and paraspinal invasion. The patient had undergone a first palliative decompression and fixation surgery, and the diagnosis turned out to be a World Health Organization grade III anaplastic meningioma based on histopathology...

Purpose For pharmaceutical, biological and biomedical applications the functionalization of gold surfaces with pH-sensitive groups has great potential. The aim of this work was to modify gold surfaces with pH-sensitive groups and to determine the pKa of the modified gold surfaces using a fluorescent nanoparticle adhesion assay. Methods To introduce pH-sensitive groups onto gold surfaces, we modified gold-coated silicon slides with four different bases: 4-mercaptopyridine (4-MP), 4-pyridylethylmercaptan (4-PEM), 4-aminothiophenol (4-ATP), and 2-mercaptoethylamine (2-MEA)...

Mechanically robust polymer electrolyte membranes (PEMs) exhibiting high ionic conductivity at ambient temperature are a prerequisite for next-generation electrochemical devices. We utilized a polymerization-induced microphase separation (PIMS) strategy to prepare nanostructured materials comprising continuous conducting nanochannels intertwined with a mechanically and thermally robust cross-linked polymeric framework. Addition of succinonitrile (SN) rendered the poly(ethylene oxide)/lithium (Li) salt conducting domains completely amorphous, resulting in outstanding conductivities (∼0...

Whites' nonprejudiced behavior toward racial/ethnic minorities can be attributionally ambiguous for perceivers, who may wonder whether the behavior was motivated by a genuine internal commitment to egalitarianism or was externally motivated by desires to avoid appearing prejudiced to others. This article reports the development of a scale that measures perceptions of Whites' internal and external motives for avoiding prejudice (Perceived Internal Motivation Scale/Perceived External Motivation Scale [PIMS/PEMS]) and tests of its internal, test-retest, discriminant, convergent, and predictive validity among ethnic minority perceivers...

Noninvasive mechanical ventilation through a nasal mask is a recently introduced therapeutic tool that represents a noteworthy advance in home treatment for patients with respiratory insufficiency secondary to ventilatory pump failure. We present the preliminary results of a program for early detection of respiratory insufficiency in patients with Duchenne's disease. Sixteen patients (mean age 15.8 years) with this disease were evaluated between January 1994 and January 1995. Mean lung function parameters were FVC 1,440 ml (46...

Pulmonary function and respiratory muscle strength was assessed in 20 patients with mitral stenosis uncomplicated by other illness. Pulmonary function was evaluated by spirometry, flow-volume curves, functional residual capacity (FRC) and total lung capacity (TLC). Respiratory muscle strength was evaluated by measurement of maximal static inspiratory and expiratory mouth pressure (PIM, PEM cmH2O) at FRC and TLC respectively. Spirometric, FRC and TLC average values were normal. The maximal expiratory flow rate at 50 and 25% of vital capacity were decreased to 49...