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The primary objective of this review is to develop practice-based expert group opinions on the cardiovascular (CV) safety and utility of modern sulfonylureas (SUs) in cardiovascular outcome trials (CVOTs).

Summary The Cyclops massif (Irian Jaya - Western Indonesia) displays all components of an ophiolitic sequence including residual mantle peridotites (harzburgites and dunites), cumulate gabbros, dolerites, normal mid-oceanic ridge basalts (N-MORB) and minor amounts of boninitic lavas. This ophiolitic series tectonically overlies high temperature (HT)-high pressure (HP) mafic rocks metamorphosed during the Miocene.

We have studied the NO-CO-O2reaction over a Rh(111) catalyst by monitoring the reaction products (CO2, N2O, and N2) and the infrared (IR) intensity of surface CO and NO at various partial pressures of NO, CO and O2, and sample temperatures. The selectivity for N2O formation, apparent activation energy for product formation, and NO consumption rate during NO-CO-O2are identical to those measured during the NO-CO reaction. The IR measurements show that during NO-CO-O2the same two adsorbed species, NO at 1640 cm-1and linear CO at ~2040 cm-1, are present in the same surface concentrations as during NO-CO. For this reason the NO-CO-O2kinetics are dominated by the NO-CO kinetics, the NO consumption is rate limited by dissociation of adsorbed NO, and the N2O selectivity is dominated by surface NO coverage. In contrast, O2consumption is adsorption rate limited with the NO-CO adsorption-desorption equilibrium controlling the vacant sites required to dissociatively adsorb O2. These kinetic and IR data of the CO-NO-O2reaction and our interpretation of them agree with previous studies over supported Rh catalysts and thus confirm the previously proposed explanation. From RAIRS and kinetic data we estimate the rate constant for the CO+O→CO2elementary step. The pre-exponential factor for this rate is 2×1010s-1, a factor of 50 smaller than previous estimates. This rate constant is important to the NO-CO-O2kinetics because it affects O coverage, which, under certain conditions, inhibits NO consumption.

Surface morphologies of molybdenum-based catalysts supported on graphite were investigated with a scanning tunneling microscope. The oxide phases of Mo, Co, and Mo-Co were observed to form distinct types of clusters on graphite. MoOx clusters appeared to be elliptical, with sizes ranging from 100 to 200 Å in length and 60 Å in width, while CoOx formed round and needle-shaped clusters, about 200 Å in size. Oxidized Co-Mo was observed to form ringtype structures which were uniformly 100 Å in diameter. This ring-type structure was attributed to the CoMoOx structure with Co decorating the edges of Mo. Sulfided phases of these catalysts were observed to form large slabs on graphite. Sulfided MoOx formed large islands (100 Å × 150 Å). These may be formed from the aggregation of small MoS2 crystallites. Besides forming large patches, CoS also formed needle-type clusters similar to CoOx, but smaller (120 Å) in length. These clusters and patches are believed to be bulk Co9S8. Sulfided CoMoOx formed CoMoS islands similar to the needle-type clusters observed in CoS, but much larger in size, from 300 to 600 Å. No MoS2 and CoS types of clusters were observed on this sample. No apparent movement of the clusters was observed during repeated scanning, suggesting that there is an interaction between the cluster and the graphite support.

We have studied the reaction of NO with CO over a Rh(111) catalyst by monitoring the infrared (IR) intensity of surface CO and NO at various partial pressures of NO (PNO), CO (PCO), and sample temperatures (T). Reaction rates for the products (CO2, N2O, and N2) were previously measured at the same conditions in our apparatus [J. Phys. Chem.99, 16344 (1995)]. Surface coverages were observed both atPNO=8 Torr, where the reaction yields mostly N2O and the selectivity is insensitive to eitherPCO(1 to 40 Torr) orT(<673 K), and atPNO=0.8 Torr, where the major product changes from N2O below 635 K to N2above 635 K. Changes in the surface coverages of NO and CO correlate well with the observed changes in N2O selectivity. Below 635 K, where N2O formation is favored, NO dominates the surface. Above 635 K, where N2formation is preferred, CO is the majority surface species. Our IR data support a model in which product N2O and N2are formed as adsorbed N reacts with either adsorbed NO or N, respectively. In an additional kinetic experiment, we used isotopically labeled N2O to show that gas phase N2O is not an intermediate to N2formation at 648 K—this helps to rule out an alternative model. In our IR experiments, two types of spectra were obtained with a Fourier transform IR spectrometer. Polarization spectra were obtained using two fixed polarizers, one before the sample, oriented to pass approximately equal amounts ofs- andp-polarized light, and one after the sample that selecteds- orp-polarized light. Spectra obtained withs- andp-polarized light were ratioed. We also obtained conventional reflectance absorbance IR spectra. In a separate calibration experiment with NO on Rh(111) in ultrahigh vacuum we observed five IR bands at 1448, 1530, 1590, 1643, and 1693 cm−1. We attribute all of these to bridging NO, most likely at threefold hollow sites. As NO coverage increases up to saturation, the distribution of population among these bands (and their individual frequencies) gradually changes—the average vibrational frequency of the NO increases from ∼1440 to ∼1650cm−1. From the linear dependence of the integrated IR absorption on NO coverage we find that the vibrational polarizability of the adsorbed NO is 0.20±0.02 Å3, a factor 6.5 larger than for free NO. This increase, proportionally larger than for CO on transition metal surfaces, is explained by the facile charge transfer that accompanies donor–acceptor bonding between NO and Rh(111).

The adlayer structure of (2 × 2)-3NO on Rh(111) has been investigated by high-energy, scanned-angle X-ray photoelectron diffraction (XPD) in conjunction with single scattering cluster theory and R-factor analysis. In addition, a plausible adlayer registry, consistent with previously published HREELS data, is deduced by means of physical reasoning. The resulting structural model consists of NO bound to atop, three-fold hollow fcc, and three-fold hollow hcp sites through the N atom with an NO bond length of 1.15 Å. NO molecules at all three sites within the adlayer are oriented normal to the surface. The Zcoordinates (Zbeing defined as perpendicular to the surface) of atop and hollow-site NO molecules relative to the top layer of Rh atoms differ by 0.5 Å, with hollow-site NO being bound more closely to the substrate. This structure differs considerably from one proposed previously by a LEED I-Vanalysis in both the site occupancy and the spacing of NO molecules within the adlayer.

In quantum system, particles are messenger. They bring polarization information. This characteristic is used in cryptography as the digital information transmitter in a symmetric as well as an asymmetric quantum key distribution. This paper presented the simulation of a symmetric quantum key distribution. The presence of an eavesdropper was included in the simulation.

Thermal Radiation Experiments Kit (TREK) based on data logger for physics learning media was developed. TREK will be used as a learning medium on the subject of Temperature and Heat to explain the concept of emissivity of a material in grade XI so that it can add variations of experiments which are commonly done such as thermal expansion, transfer of thermal energy (conduction, convection, and radiation), and specific heat capacity. DHT11 sensor is used to measure temperature and microcontroller Arduino-uno used as data logger. The object tested are in the form of coated glass thin films and aluminum with different colors. TREK comes with a user manual and student worksheet (LKS) to make it easier for teachers and students to use. TREK was developed using the ADDIE Development Model (Analyze, Design, Development, Implementation, and Evaluation). And validated by experts, physics teachers, and students. Validation instrument is a questionnaire with a five-item Likert response scale with reviewed aspect coverage: appropriate content and concepts, design, and user friendly. The results showed that TREK was excellent (experts 88.13%, science teachers 95.68%, and students 85.77%).