Carbon-Methanol Based Adsorption Heat Pumps: Identifying Accessible Parameter Space with Carbide-Derived Carbon Model Materials

In adsorption heat pumps, the properties of the porous adsorbent and the refrigerant determine the performance. Major parameters for this working pair are the total uptake of the adsorptive, its kinetics, and the heat transfer characteristics. In the technical application despite powdered adsorbents, thin consolidated layers of the adsorbent can be attractive and obtained by a binder-based approach but likely result in competing material properties. Thus, for a process optimization, the accessible parameter space and interdependencies have to be known and were deduced in this work for model porous carbons (carbide-derived carbons derived from TiC and ZrC) and methanol as well as the addition of different amounts of boron nitride, silver, and graphite as heat-conductive agents and the use of two binders.     

Effect of target peak power density on the phase formation,microstructure evolution,and mechanical properties of Cr2AlC MAX-phase coatings

The applicability of Cr₂AlC MAX-phases as protective coatings in energy conversion or aerospace applications requires a dense, single-phase structure. Therefore, we study the effect of target power density and substrate bias on phase formation, microstructure evolution, and mechanical properties of Cr₂AlC coatings utilizing direct current (DCMS) and high-power pulsed magnetron sputtering (HPPMS). Generally, HPPMS results in coatings with superior density and hence larger elastic moduli compared to DCMS, indicating that ion bombardment by ionized film-forming species is beneficial. However, decreasing the substrate bias to ?200 V for DCMS and ?100 V for HPPMS favors the ion bombardment induced formation of the disordered (Cr,Al)₂C_x solid solution. It is evident that there is an optimum moderate ion energy for the formation of dense Cr₂AlC coatings. Too low energy results in the formation of under-dense coatings. Too high energy yields the formation of (Cr,Al)₂C_x in addition to Cr₂AlC.     

Videoendoscopic swallowing study for diagnosis of Zenker''s diverticuli

Eight nonhaemophilic patients with factor VIII (FVIII) inhibitors were reported. There was no difference in sex distribution. Median age at diagnosis was 62 years (ranging from 14 to 73 years). No associated disorders were revealed and all the patients were presented with severe muscular or arthral bleeding. Inhibitor titre was measured by the Bethesda method, which were 6.4, 126.0, 155.0, 4.8, 56.0, 13.5, 35.0 and 150.0 BU mL-1, respectively, at diagnosis. FVIII:C levels were less than 1 U dL-1 in seven patients and less than 2 U dL-1 in one patient. The median vWF:Ag level was 210% (ranging from 80% to 340%). All the patients had good response to activated prothrombin complex concentrates for acute bleeding episodes and prednisone for inhibitor elimination. Inhibitors completely eliminated in seven patients within a follow-up duration over 1 year, and one patient died of intracranial haemorrhage when her inhibitor titre decreased to 4.5 BU mL-1 and FVIII:C increased to 21 U dL-1.     

Glassomer—Processing Fused Silica Glass Like a Polymer

Fused silica glass is one of the most important high‐performance materials for scientific research, industry, and society. However due to its high chemical and thermal resistance as well as high hardness, fused silica glass is notoriously difficult to structure. This work introduces Glassomer, a solid nanocomposite, which can be structured using polymer molding and subtractive technologies at submicrometer resolution. After polymer processing Glassomer is turned into optical grade fused silica glass during a final heat treatment. The resulting glass has the same optical transparency as commercial fused silica and a smooth surface with a roughness of a few nanometers. This work makes high‐performance fused silica glass components accessible to high‐throughput fabrication technologies and will enable numerous optical, photonic and medical applications in science and industry.     

Renal and cardiac complications of drug abuse

The case is presented of a young man who, after prolonged intravenous narcotic administration, developed subacute bacterial endocarditis involving the aortic valve, and rapidly progressive glomerulonephritis. After treatment of and recovery from renal failure, persistent proteinuria was shown to be caused by focal glomerulosclerosis. The association of these lesions with "mainlining" is reviewed.     

A Super-Resolution Framework for High-Accuracy Multiview Reconstruction

We present a variational framework to estimate super-resolved texture maps on a 3D geometry model of a surface from multiple images. Given the calibrated images and the reconstructed geometry, the proposed functional is convex in the super-resolution texture. Using a conformal atlas of the surface, we transform the model from the curved geometry to the flat charts and solve it using state-of-the-art and provably convergent primal–dual algorithms. In order to improve image alignment and quality of the texture, we extend the functional to also optimize for a normal displacement map on the surface as well as the camera calibration parameters. Since the sub-problems for displacement and camera parameters are non-convex, we revert to relaxation schemes in order to robustly estimate a minimizer via sequential convex programming. Experimental results confirm that the proposed super-resolution framework allows to recover textured models with significantly higher level-of-detail than the individual input images.     

Large scale graph-based SLAM using aerial images as prior information

The problem of learning a map with a mobile robot has been intensively studied in the past and is usually referred to as the simultaneous localization and mapping (SLAM) problem. However, most existing solutions to the SLAM problem learn the maps from scratch and have no means for incorporating prior information. In this paper, we present a novel SLAM approach that achieves global consistency by utilizing publicly accessible aerial photographs as prior information. It inserts correspondences found between stereo and three-dimensional range data and the aerial images as constraints into a graph-based formulation of the SLAM problem. We evaluate our algorithm based on large real-world datasets acquired even in mixed in- and outdoor environments by comparing the global accuracy with state-of-the-art SLAM approaches and GPS. The experimental results demonstrate that the maps acquired with our method show increased global consistency.     

Occurrence of cotton herbicides and insecticides in playa lakes of the High Plains of West Texas

During the summer of 1997, water samples were collected and analyzed for pesticides from 32 playa lakes of the High Plains that receive drainage from both cotton and corn agriculture in West Texas. The major cotton herbicides detected in the water samples were diuron, fluometuron, metolachlor, norflurazon, and prometryn. Atrazine and propazine, corn and sorghum herbicides, were also routinely detected in samples from the playa lakes. Furthermore, the metabolites of all the herbicides studied were found in the playa lake samples. In some cases, the concentration of metabolites was equal to or exceeded the concentration of the parent compound. The types of metabolites detected suggested that the parent compounds had been transported to and had undergone degradation in the playa lakes. The types of metabolites and the ratio of metabolites to parent compounds may be useful in indicating the time that the herbicides were transported to the playa lakes. The median concentration of total herbicides was 7.2 microg/l, with the largest total concentrations exceeding 30 microg/l. Organophosphate insecticides were detected in only one water sample. Further work will improve the understanding of the fate of these compounds in the playa lake area.     

Effects of Sulfur Additive EP in Ester Coolants during Friction with CBN

A study was undertaken to investigate the effects of the EP additives during tribological tests using a CBN tool against steel. Ester oil with and without sulfur additive were used as lubricants in a tribometer. Tribochemical interactions between the S additive and steel have been investigated under boundary lubrication conditions by SEM and EDX analysis. The relative abundance of different elements on the surface of the CBN tools, which are present in the workpiece material such as Fe (iron) and Cr (chromium), suggests that adhesion occurred when the ester oil without sulfur additive was tested. Tribochemical interactions between the additive and the steel could be observed when using the ester oil containing the sulfur additive. These interactions contribute to the formation of a uniform layer on the CBN tool. This layer is composed by S (sulfur), Fe, and O (oxygen). The presence of these elements indicate that FeO (iron oxide) and FeS (iron sulfide) were formed.