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Laser diagnostics for the study of heterogeneous catalysis

In heterogeneous catalysis the reactions occur on the surface of a catalyst. To understand the reaction pathways, a detailed understanding on an atomic level is critical. However, the gas atmosphere surrounding the surface dictates the interaction between the surface and the gas. At low pressures this is often neglected, but as the community turns to higher pressures it becomes important to consid

Recent development of methods based on structured illumination for combustion studies

Structured illumination is an imaging method most commonly employed within the field of microscopy. However, recently the technique has spread into other scientific fields, such as for combustion research, where it has revealed new measurement opportunities. This paper describes how structured illumination can be employed for spray- and combustion research and highlights some of the recent progres

New data-driven estimation of terrestrial CO2 fluxes in Asia using a standardized database of eddy covariance measurements, remote sensing data, and support vector regression

The lack of a standardized database of eddy covariance observations has been an obstacle for data-driven estimation of terrestrial CO2 fluxes in Asia. In this study, we developed such a standardized database using 54 sites from various databases by applying consistent postprocessing for data-driven estimation of gross primary productivity (GPP) and net ecosystem CO2 exchange (NEE). Data-driven est

Thermometry in porous media using GASMAS - a feasibility study

The line shape of an absorption line from molecular oxygen enclosed in the pores of a ceramic material has been studied at different temperatures. By evaluating the line width it is feasible to extract temperature information of the gas inside porous scattering materials.

The interactive effect of demographic and clinical factors on hippocampal volume : A multicohort study on 1958 cognitively normal individuals

Alzheimer's disease is characterized by hippocampal atrophy. Other factors also influence the hippocampal volume, but their interactive effect has not been investigated before in cognitively healthy individuals. The aim of this study is to evaluate the interactive effect of key demographic and clinical factors on hippocampal volume, in contrast to previous studies frequently investigating these fa

Effects of exhaust gas recirculation at various loads on diesel engine performance and exhaust particle size distribution using four blends with a research octane number of 70 and diesel

Partially premixed combustion using gasoline-like fuels on compression ignition engines shows great potentials to break the soot-nitrogen oxides trade off and reduce both emissions simultaneously. By simply adjusting the dilution strategies and injection events, the control of partially premixed combustion is relatively easier compared to other low-temperature combustion concepts. However despite

The reconnaissance drought index : A method for detecting regional arid climatic variability and potential drought risk

The impact of climate variability on water demand and availability in drylands is substantial. Establishing methods to analyse precipitation (P) and evapotranspiration data sets may generate useful tools that assist in drought recognition and regional variations therein. The authors developed an index that simultaneous integrates both these variables in climate variability analysis. This study pro

Adaptive sequence evolution is driven by biotic stress in a pair of orchid species (Dactylorhiza) with distinct ecological optima

The orchid family is the largest in the angiosperms, but little is known about the molecular basis of the significant variation they exhibit. We investigate here the transcriptomic divergence between two European terrestrial orchids, Dactylorhiza incarnata and Dactylorhiza fuchsii, and integrate these results in the context of their distinct ecologies that we also document. Clear signals of lineag

Elimination of Lateral Resistance and Current Crowding in Large-Area LEDs by Composition Grading and Diffusion-Driven Charge Transport

Gallium nitride based light-emitting diodes (LEDs) are presently fundamentally transforming the lighting industry, but limitations in the materials and fabrication methods of LEDs introduce substantial challenges to their future development. Among the remaining key bottlenecks of GaN LEDs are the resistive losses and current crowding that strongly increase the heat generation at high powers. In th

The effect of local land-use changes on floristic diversity during the past 1000 years in southern Sweden

The relationship between land-use and floristic diversity in the landscape, for the last millennia, is analysed from two small lakes in southern Sweden. Pollen analysis and the Local Vegetation Estimates (LOVE) model are used to quantify land-cover at local scales with 100-year time windows. Floristic richness is estimated using palynological richness, and we introduce LOVE-based evenness as a pro

Crystal structure refinement of chromites from two achondrites, their T-f(O2) conditions, and implications

Six Cr-spinel grains from NWA 6077 brachinite-like and NWA 725 winonaite achondrites have been studied by single-crystal X-ray diffraction and structural refinement. From a chemical point of view, spinels from NWA 6077 show Cr/(Cr + Al) (i.e., Cr#) and Mg/(Mg + Fe2+) (i.e., Mg#) values similar to other brachinites, while the Cr# of NWA 725 is lower than that of literature winonaites. Spinels from

Entropy solutions of a scalar conservation law modeling sedimentation in vessels with varying cross-sectional area

The sedimentation of an ideal suspension in a vessel with variable cross-sectional area can be described by an initial-boundary value problem for a scalar nonlinear hyperbolic conservation law with a nonconvex flux function and a weight function that depends on spatial position. The sought unknown is the local solids' volume fraction. For the most important cases of vessels with downward-decreasin

User Body Effect on Phased Array in User Equipment for the 5G mmWave Communication System

The millimeter-wave phased array in the user equipment (UE) for 5G communication is studied in this letter. In particular, the body effect on the phased array in the UE at 15 GHz is investigated with the 3-D measurement data, and its impact on some key parameters for phased array in the UE, such as the total scan pattern, the coverage efficiency, and the probability of detection, are analyzed.

Zircon growth during progressive recrystallization of Gabbro to Garnet Amphibolite, Eastern Segment, Sveconorwegian orogen

The interpretation of whether a dated metamorphic zircon generation grew during the prograde, peak or retrograde stage of a metamorphic cycle is critical to geological interpretation. This study documents a case at Herrestad, in the eastern part of the 1±0 Ga Sveconorwegian Province, involving progressive metamorphic recrystallization of gabbro to garnet amphibolite and associated behaviour of Zr-