scholarly journals Determining the lithogeochemical background concentrations of 39 elements in Bavarian rocks

2021 ◽  
Author(s):  
Bernhard Wagner ◽  
Anneke Tammen ◽  
Dietmar Jung
Keyword(s):  
Trace Elements ◽  
Open Source ◽  
Large Majority ◽  
Background Concentrations ◽  
Statistical Parameters ◽  
Typical Element ◽  
Background Values ◽  
Web Map ◽  
Source Program ◽  
Geological Map

Abstract Typical element background concentrations of rock units in Bavaria were evaluated by statistical means and presented in a lithogeochemical map, derived from the geological map at a scale of 1:25,000. The elements include 39 geogenic main and trace elements (SiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O, TiO2, P2O5 Li, Be, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, Tl, Pb, Bi , Th and U). The distributions of element concentrations in the lithogeochemical units follow closely lognormal patterns in a large majority of cases. Statistical parameters (10th, 25th, 50th, 75th, 90th percentiles) of investigated elements were determined using the cenfit function of the NADA package within the open source program R. The investigation, based on 8,838 analysed samples, provided data for about 2/3 of the area of Bavaria. The lithogeochemical map with medians (50th percentiles) and background values (90th percentiles) of the investigated elements is available in a web map application. Thus, the regional geogenic background values of the investigated elements in Bavaria are publicly available for a large variety of applications.

scholarly journals Usage of Web Map Tile Service for the Seamless Digital Geological Map of Japan using Free and Open Source Software

2013 ◽  
Vol 24 (3) ◽  
pp. 125-132
Author(s):  
Susumu NONOGAKI ◽  
Yoshiharu NISHIOKA ◽  
Daisaku KAWABATA ◽  
Tatsuya NEMOTO ◽  
Kaoru KITAO
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Web Map ◽  
Geological Map

scholarly journals AutoMeKin2021 : An open‐source program for automated reaction discovery

2021 ◽  
Author(s):  
Emilio Martínez‐Núñez ◽  
George L. Barnes ◽  
David R. Glowacki ◽  
Sabine Kopec ◽  
Daniel Peláez ◽  
...  
Keyword(s):  
Open Source ◽  
Reaction Discovery ◽  
Open Source Program ◽  
Source Program

The Rise of Open Source Program Office

2021 ◽  
Vol 23 (1) ◽  
pp. 27-33
Author(s):  
Hussan Munir ◽  
Carl-Erik Mols
Keyword(s):  
Open Source ◽  
Open Source Program ◽  
Source Program

Control of Void Formation in Adhesively Bonded Joints in the Presence of Filler

2020 ◽  
Vol 2020 (1) ◽  
pp. 000246-000258
Author(s):  
Nina S. Dytiuk ◽  
Thomas F. Marinis ◽  
Joseph W. Soucy
Keyword(s):  
Finite Element ◽  
Open Source ◽  
Void Formation ◽  
Adhesive Joints ◽  
Bonded Joints ◽  
Volatile Species ◽  
Adhesively Bonded ◽  
Adhesively Bonded Joints ◽  
Open Source Program ◽  
Source Program

Abstract Adhesively bonded joints are ubiquitous in electronic assemblies that are used in a wide range of applications, which include automotive, medical, military, space and communications. The steady drive to reduce the size of assemblies in all of these applications, while providing increased functionality, generates a need for adhesive joints of higher strength, improved thermal and electrical conductivity and better dielectric isolation. All of these attributes of adhesive joints are degraded by the presence of voids in them. The quest to minimize voids in bonded structures motivated a previous study of their formation in a solvent cast, die bond epoxy film, which undergoes a liquid phase transition during cure. That work is extended in this study by including the effects of various filler morphologies in the adhesive. Fillers are added to adhesives to facilitate handling of thin sheet formats, control bond line thickness and reduce coefficient of thermal expansion. As such, fillers are selected to be inert with respect to the adhesive chemistry, while being readily wetted by it in the liquid state. Common filler morphologies include woven and molded open meshes, fibers chopped to uniform length, and spheres of uniform or distributed diameters. Void formation is influenced by a number factors, which include wettability of the bonded surfaces, adsorbed water, amount of solvent retained in the film, volume of entrapped air, thermal profile of the cure schedule, and clamping pressure during cure. The presence of fillers in the adhesive adds the additional factors of constrained diffusion paths and increased area for void nucleation. We have changed our approach to modeling the diffusion of volatile species in adhesive joints from a finite difference calculation in a uniform adhesive medium used previously, to a finite element model of a complex diffusion space. The open source program Gmsh is used to generate the diffusion space from a set of input parameters. The calculations of concentration profiles and diffusion fluxes of volatile species at the void interface are made using the open source finite element program elmer. As done previously, the position of the void interface is updated by integrating the product of time and flux of diffusing species over the area of the interface. The internal pressure of the void is determined by application of the Young-Laplace equation, while Henry’s law is used to estimate the concentration of diffusing species adjacent to the void interface. The calculation proceeds for a time equivalent to the integral of the time temperature product required to achieve a 70% cure state of the adhesive, at which point the void interface is immobile. The experimental approach is the same as used previously, with the filled adhesive sandwiched between glass slides and cured on a hot plate while imaged through a microscope. Images are automatically captured and analyzed by using the open source program imageJ, which allows us to track the evolution of individual voids as well as the time dependent distribution of the void population. We are working to correlate these experimental results with the predictions of our finite element calculations to allow us to make insightful choices of adhesives and optimize our bonding processes.

An open-source program to analyze spontaneous sympathetic neurohemodynamic transduction

2021 ◽  
Vol 125 (3) ◽  
pp. 972-976
Author(s):  
Myles W. O’Brien ◽  
Jennifer L. Petterson ◽  
Derek S. Kimmerly
Keyword(s):  
Open Source ◽  
Sympathetic Nerve Activity ◽  
Muscle Sympathetic Nerve Activity ◽  
Analysis Program ◽  
Microsoft Excel ◽  
Nerve Activity ◽  
Source Program ◽  
Pressor Responses ◽  
Sympathetic Regulation ◽  
High Level

The pressor responses to spontaneous bursts of muscle sympathetic nerve activity provide important information regarding sympathetic regulation of the circulation. Many laboratories worldwide quantify sympathetic neurohemodynamic transduction using in-house, customized software requiring high-level programming skills and/or costly computer programs. To overcome these barriers, this study presents a simple, open-source, Microsoft Excel-based analysis program along with video instructions to assist researchers without the necessary resources to quantify sympathetic neurohemodynamic transduction.

scholarly journals Trace metal distribution in pristine permafrost-affected soils of the Lena River Delta and its Hinterland, Northern Siberia, Russia

2013 ◽  
Vol 10 (2) ◽  
pp. 2205-2244 ◽  
Author(s):  
I. Antcibor ◽  
S. Zubrzycki ◽  
A. Eschenbach ◽  
L. Kutzbach ◽  
D. Bol'shiyanov ◽  
...  
Keyword(s):  
Trace Elements ◽  
Organic Matter ◽  
Trace Metal ◽  
Climatic Changes ◽  
River Delta ◽  
Metal Distribution ◽  
Background Concentrations ◽  
Lena River ◽  
Trace Metal Distribution ◽  
Lena River Delta

Abstract. Soils are an important compartment of ecosystems and have the ability to immobilize chemicals preventing their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since the Arctic ecosystems are considered to be very sensitive to climatic changes as well as to chemical contamination. This study characterizes background levels of trace metals in permafrost-affected soils of the Lena River Delta and its hinterland in northern Siberia (73.5° N–69.5° N) representing a remote region far from evident anthropogenic trace metal sources. Investigations on total element contents of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co) and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest concentrations of the majority of the measured elements were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) in the Lena River Delta region. Correlation analyses of trace metal concentrations and soil chemical and physical properties at a Holocene estuarine terrace and two modern floodplain levels in the southern-central Lena River Delta (Samoylov Island) showed that the main factors controlling the trace metal distribution in these soils are organic matter content, soil texture and contents of iron and manganese-oxides. Principal Component Analysis (PCA) revealed that soil oxides play a significant role in trace metal distribution in both top and bottom horizons. Occurrence of organic matter contributes to Cd binding in top soils and Cu binding in bottom horizons. Observed ranges of the background concentrations of the majority of trace elements were similar to background levels reported for other pristine arctic areas and did not exceed mean global background concentrations examined for the continental crust as well as for the world's soils.

scholarly journals QSAR-Co-X: An Open Source Toolkit for Multi-Target QSAR Modelling

2020 ◽  
Author(s):  
M. Natália Dias Soeiro Cordeiro ◽  
Amit Kumar Halder
Keyword(s):  
Open Source ◽  
Linear Models ◽  
Moving Average ◽  
Biological Data ◽  
Statistical Parameters ◽  
Computational Tools ◽  
Qsar Modelling ◽  
Qsar Models ◽  
Quantitative Structure Activity Relationships ◽  
Set Up

Abstract Quantitative structure activity relationships (QSAR) modelling is a well-known computational tool, often used in a wide variety of applications. Yet one of the major drawbacks of conventional QSAR modelling tools is that models are set up based on a limited number of experimental and/or theoretical conditions. To overcome this, the so-called multitasking or multi-target QSAR (mt-QSAR) approaches have emerged as new computational tools able to integrate diverse chemical and biological data into a single model equation, thus extending and improving the reliability of this type of modelling. We have developed QSAR-Co-X, an open source python−based toolkit (available to download at https://github.com/ncordeirfcup/QSAR-Co-X) for supporting mt-QSAR modelling following the Box-Jenkins moving average approach. The new toolkit embodies several functionalities for dataset selection and curation plus computation of descriptors, for setting up linear and non-linear models, as well as for a comprehensive results analysis. The workflow within this toolkit is guided by a cohort of multiple statistical parameters along with graphical outputs onwards assessing both the predictivity and the robustness of the derived mt-QSAR models. To monitor and demonstrate the functionalities of the designed toolkit, three case-studies pertaining to previously reported datasets are examined here. We believe that this new toolkit, along with our previously launched QSAR-Co code, will significantly contribute to make mt-QSAR modelling widely and routinely applicable.

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