Characterization of exchange flow in vertical pipes of circular and square cross-sections under unstable density gradient

Characterization of top-surface of NiCrAlY coating deposited by plasma spraying process on Inconel 625 Ni based superalloys was analyzed in two different completely conditions. First of them was as sprayed state of NiCrAlY coating and the second one was condition after grinding process. The basic aim of this treatment was related to obtain totally different conditions of coatings surface especially from roughness point of view. Those two types of top surface morphology was a base to comparison of oxidation resistant during static oxidation test at temperature of 1000°C and 1100°C. The temperature of static oxidation test was 1000°C and 1100°C. The specimens were moved out from furnace after 25, 300, 500, 750 and 1000 hours of exposition in laboratory air. The range of investigations after each interval included top surface characterization of specimens by SEM, XRD and EDS method. Those investigations showed that different types of top surface conditions had a fundamental influence on oxides layer morphology. Especially in the case of phase`s constituent of oxides zone. More detailed investigations were made on the cross sections of two types of investigated specimens. Analysis of oxides layer morphology showed in this case basic differences in thickness of oxides zone which was much higher in the case of as sprayed NiCrAlY coating.

Download Full-text

A Novel Approach to Characterize the Lipidome of Marine Archaeon Nitrosopumilus maritimus by Ion Mobility Mass Spectrometry

Frontiers in Microbiology ◽

10.3389/fmicb.2021.735878 ◽

2021 ◽

Vol 12 ◽

Author(s):

Kai P. Law ◽

Wei He ◽

Jianchang Tao ◽

Chuanlun Zhang

Keyword(s):

Mass Spectrometry ◽

Cross Sections ◽

Ion Mobility ◽

Resolving Power ◽

Ion Mobility Mass Spectrometry ◽

Ion Chemistry ◽

Lipid Species ◽

Mobility System ◽

Archaeal Lipids

Archaea are differentiated from the other two domains of life by their biomolecular characteristics. One such characteristic is the unique structure and composition of their lipids. Characterization of the whole set of lipids in a biological system (the lipidome) remains technologically challenging. This is because the lipidome is innately complex, and not all lipid species are extractable, separable, or ionizable by a single analytical method. Furthermore, lipids are structurally and chemically diverse. Many lipids are isobaric or isomeric and often indistinguishable by the measurement of mass or even their fragmentation spectra. Here we developed a novel analytical protocol based on liquid chromatography ion mobility mass spectrometry to enhance the coverage of the lipidome and characterize the conformations of archaeal lipids by their collision cross-sections (CCSs). The measurements of ion mobility revealed the gas-phase ion chemistry of representative archaeal lipids and provided further insights into their attributions to the adaptability of archaea to environmental stresses. A comprehensive characterization of the lipidome of mesophilic marine thaumarchaeon, Nitrosopumilus maritimus (strain SCM1) revealed potentially an unreported phosphate- and sulfate-containing lipid candidate by negative ionization analysis. It was the first time that experimentally derived CCS values of archaeal lipids were reported. Discrimination of crenarchaeol and its proposed stereoisomer was, however, not achieved with the resolving power of the SYNAPT G2 ion mobility system, and a high-resolution ion mobility system may be required for future work. Structural and spectral libraries of archaeal lipids were constructed in non-vendor-specific formats and are being made available to the community to promote research of Archaea by lipidomics.

Download Full-text

Surface characterization of pretreated and microbial-treated populus cross-sections

10.2172/1376618 ◽

2017 ◽

Author(s):

Allison K. Tolbert

Keyword(s):

Cross Sections ◽

Surface Characterization

Download Full-text

Worth a Closer Look: Raman Spectra of Lead-Pipe Scale

Minerals ◽

10.3390/min11101047 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1047

Author(s):

Jill Dill Pasteris ◽

Yeunook Bae ◽

Daniel E. Giammar ◽

Sydney N. Dybing ◽

Claude H. Yoder ◽

...

Keyword(s):

Cross Sections ◽

Water System ◽

Analytical Techniques ◽

Real Time Analysis ◽

Fiber Optic Probes ◽

Lead Pipe ◽

Lead Pipes ◽

Non Destructive

The identification and characterization of lead-bearing and associated minerals in scales on lead pipes are essential to understanding and predicting the mobilization of lead into drinking water. Despite its long-recognized usefulness in the unambiguous identification of crystalline and amorphous solids, distinguishing between polymorphic phases, and rapid and non-destructive analysis on the micrometer spatial scale, the Raman spectroscopy (RS) technique has been applied only occasionally in the analysis of scales in lead service lines (LSLs). This article illustrates multiple applications of RS not just for the identification of phases, but also compositional and structural characterization of scale materials in harvested lead pipes and experimental pipe-loop/recirculation systems. RS is shown to be a sensitive monitor of these characteristics through analyses on cross-sections of lead pipes, raw interior pipe walls, particulates captured in filters, and scrapings from pipes. RS proves to be especially sensitive to the state of crystallinity of scale phases (important to their solubility) and to the specific chemistry of phases precipitated upon the introduction of orthophosphate to the water system. It can be used effectively alone as well as in conjunction with more standard analytical techniques. By means of fiber-optic probes, RS has potential for in situ, real-time analysis within water-filled pipes.

Download Full-text

Optical characterization of tristructural isotropic fuel particle cross-sections using generalized ellipsometry

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2006.02.081 ◽

2006 ◽

Vol 352 (1-3) ◽

pp. 6-12 ◽

Cited By ~ 17

Author(s):

G.E. Jellison ◽

J.D. Hunn ◽

R.A. Lowden

Keyword(s):

Cross Sections ◽

Optical Characterization ◽

Fuel Particle

Download Full-text

The Relative Importance of Wind Straining and Gravitational Forcing in Driving Exchange Flows in Tidally Energetic Estuaries

Journal of Physical Oceanography ◽

10.1175/jpo-d-18-0014.1 ◽

2019 ◽

Vol 49 (3) ◽

pp. 723-736 ◽

Cited By ~ 5

Author(s):

Xaver Lange ◽

Hans Burchard

Keyword(s):

Cross Sections ◽

Steady State Solution ◽

Estuarine Circulation ◽

Wind Forcing ◽

Tidal Mixing ◽

Exchange Flow ◽

Tidal Straining ◽

Tidal Estuaries ◽

Lateral Circulation ◽

Wedderburn Number

AbstractIn straight tidal estuaries, residual overturning circulation results mainly from a competition between gravitational forcing, wind forcing, and friction. To systematically investigate this for tidally energetic estuaries, the dynamics of estuarine cross sections is analyzed in terms of the relation between gravitational forcing, wind stress, and the strength of estuarine circulation. A system-dependent basic Wedderburn number is defined as the ratio between wind forcing and opposing gravitational forcing at which the estuarine circulation changes sign. An analytical steady-state solution for gravitationally and wind-driven exchange flow is constructed, where tidal mixing is parameterized by parabolic eddy viscosity. For this simple but fundamental situation, is calculated, meaning that the up-estuary wind forcing needs to be 15% of the gravitational forcing to invert estuarine circulation. In three steps, relevant physical processes are added to this basic state: (i) tidal dynamics are resolved by a prescribed semidiurnal tide, leading to caused by tidal straining; (ii) lateral circulation is added by introducing cross-channel bathymetry, smoothly increasing from 0.47 (flat bed) to 1.3 (parabolic bed) due to an increasing effect of lateral circulation on estuarine circulation; and (iii) full dynamics of a real tidally energetic inlet with highly variable forcing, where results from a two-dimensional linear regression.

Download Full-text