scholarly journals Preventing the growth of iron bacteria in water wells by copper and silver coating

2020 ◽  
Vol 20 (4) ◽  
pp. 1195-1206
Author(s):  
Georg Houben ◽  
Jürgen Sander
Keyword(s):  
Copper Coating ◽  
Silver Coating ◽  
Submersible Pump ◽  
Copper Metal ◽  
Iron Bacteria ◽  
Riser Pipe ◽  
Water Wells ◽  
Copper Coatings ◽  
Different Types ◽  
Oxide Deposition

Abstract The growth of iron-related bacteria and their deposition of iron oxides often impedes the operation of water wells, resulting in costly rehabilitation measures. The microbicidal potential of a silver and copper coating was investigated. Field-scale experiments on a riser pipe showed that silver coating only slightly subdued the growth of iron bacteria, while copper coating was highly effective. However, the coating was eroded and oxidized over the course of the experiment, rendering it ineffective. Model experiments with different types of copper coatings showed that only polished copper metal was able to prevent the growth of an iron bacteria biofilm for a longer period of time, while thinner coatings were overcome after some months. While the coating of screens, casings and riser pipes might thus not be sustainable, protecting parts of the submersible pump prone to iron oxide deposition by a copper coating could be an interesting option.

scholarly journals Calculation of the Thermal Stress when Subjected to an Electric Current on Glass and Carbon Fibers with Copper Coatings

2021 ◽  
Vol 346 ◽  
pp. 02017
Author(s):  
S. Fedorov ◽  
D. Borisov ◽  
V. Nelyub
Keyword(s):  
Electric Current ◽  
Carbon Fibers ◽  
Glass Fibers ◽  
Element Model ◽  
Copper Coating ◽  
Thermal Heating ◽  
Reinforced Plastics ◽  
Copper Coatings ◽  
Wide Range ◽  
Fiber Reinforced Plastics

Two types of fibers (carbon and glass) are considered, as an object of research, on the surface of which a copper coating is applied with a thickness of 100 nm using magnetron sputtering technology. A finite element model of a coated fiber was built and simulated in the COMSOL Multiphysics software. As a result of the calculations, the values of the temperatures, arising during the passage of electric current on the surface of the fibers and copper coating, have been determined. This calculation makes it possible to simulate the thermal heating modes occurring in parts of fiberglass and carbon fiber reinforced plastics in the process of curing. As a result of calculations, it was found that copper coating significantly improves electrical conductivity, which is especially important for glass fibers, since its conductivity is considerably lower than carbon. The use of copper coating in the production of parts from fiberglass allows to regulate their thermophysical properties within a wide range.

Temporary Wafer Bonding Materials and Processes

2012 ◽  
Vol 2012 (DPC) ◽  
pp. 001452-001476 ◽  
Author(s):  
Matthew Lueck ◽  
Alan Huffman ◽  
Marianne Butler ◽  
Dorota Temple ◽  
Phil Garrou
Keyword(s):  
Wafer Bonding ◽  
Mechanical Support ◽  
Integration Process ◽  
3D Integration ◽  
3D Ic ◽  
Ongoing Work ◽  
Different Types ◽  
Oxide Deposition ◽  
Temporary Bonding ◽  
Processing Steps

Temporary wafer bonding has been used for many years to provide mechanical support to device wafers during thinning processes. However, the advent of 2.5D and 3D integration is placing significantly higher demands on the performance of temporary bonding materials as more fabrication processes are required on progressively thinner wafers. In response, materials providers have recently developed several different types of temporary bonding solutions that seek to provide a robust carrier with a simple debond process. Typical 2.5D or 3D integration process flows will require more types of processes than just backgrinding and CMP to be done on the backside of thinned wafers. RIE, PECVD oxide deposition, lithography, and electroplating are some of the process steps that will be needed to complete the TSV interconnects. Each of these steps, and the order in which they are done, will impose certain requirements on the temporary bond material. This presentation will examine the different categories of available temporary wafer bonding solutions with regard to their bonding and debonding methods as well as their resistance to and compatibility with various BEOL processing steps. In addition, ongoing work at RTI to evaluate temporary bond materials for silicon interposer and 3D-IC applications will be presented. This work has been focusing on the interaction between these materials and the processing requirements of several photoimageable dielectrics.

Thermal Spray Deposition of A Copper Coating on Aluminium Using the Protal Process

1998 ◽  
Author(s):  
S. Ayrault-Costil ◽  
G. Montavon ◽  
C. Coddet ◽  
F. Rigollet ◽  
O. Freneaux ◽  
...  
Keyword(s):  
Thermal Spray ◽  
Spray Deposition ◽  
Surface Preparation ◽  
Copper Coating ◽  
Machine Shop ◽  
Coating Deposition ◽  
Copper Coatings ◽  
Classical Procedure ◽  
Aluminum Base ◽  
Base Substrate

Abstract In this work, the benefits of the PROTAL® process were investigated, comparing adhesion and morphology of different APS thermal spray copper coatings onto an aluminum base substrate. The PROTAL® process operates simultaneously an atmospheric thermal spray torch and a Q-switched laser (Nd:YAG) to perform surface preparation and coating deposition in a single operation. In that case, substrates are coated rough from the machine shop, i.e. without any prior surface preparation. Results obtained in this way were compared with results obtained using a classical procedure, Le, degreasing followed by sandblasting prior to coating deposition.

scholarly journals Elastic Properties of Statistically Equivalent Materials With Varying Individual Grain Orientations

1995 ◽  
Vol 25 (1) ◽  
pp. 17-24 ◽  
Author(s):  
H. Kiewel ◽  
H. J. Bunge ◽  
L. Fritsche
Keyword(s):  
Elastic Properties ◽  
Displacement Field ◽  
Elastic Moduli ◽  
Local Deformation ◽  
Deformation Field ◽  
Copper Metal ◽  
Bcc Lattice ◽  
Real Material ◽  
Different Types ◽  
Grain Orientations

The elastic properties of copper metal with different individual grain orientations exhibiting the same texture are determined. We simulate the real material by two different types of clusters. The first one consists of 365 cubic grains, the second cluster is an arrangement of 181 Wigner-Seitz cells of a body centred cubic (bcc)-lattice. For each type of cluster we let the local grain orientations vary. The displacement field inside these aggregates as a result of a homogeneous deformation acting on the surface of the clusters is calculated. Although the resulting local deformation field for different individual grain orientations varies strongly, the macroscopic elastic moduli are in the frame of this simulation identical for any cluster of the same type, as it has to be for statistically equivalent materials.

scholarly journals Antimicrobial and osteoconductive properties of two different types of titanium silver coating

2021 ◽  
Vol 41 ◽  
pp. 694-706
Author(s):  
MG Kontakis ◽  
◽  
A Diez-Escudero ◽  
H Hariri ◽  
B Andersson ◽  
...  
Keyword(s):  
Vapour Deposition ◽  
Nitride Layer ◽  
Ti6al4v Alloy ◽  
Silver Coating ◽  
Antibacterial Effects ◽  
Cementless Fixation ◽  
Future Developments ◽  
Prosthetic Joint ◽  
Different Types ◽  
Primary Human Osteoblasts

In prosthetic joint surgery, Ag coating of implant areas in direct contact with bone has been met with hesitation for fear of compromising osseointegration. The physicochemical, antibacterial and osteoconductive properties of three different Ti samples were studied: Ti6Al4V alloy that was grit-blasted (GB), Ti6Al4V alloy with an experimental Ti-Ag-nitride layer (SN) applied by physical vapour deposition (PVD) and commercially available PVD-coated Ti6Al4V alloy with a base Ag layer and a surface Ti-Ag-nitride layer (SSN, clinically known as PorAg®). Ag content on the surface of experimental SN and SSN discs was 27.7 %wt and 68.5 % wt, respectively. At 28 d, Ag release was 4 ppm from SN and 26.9 ppm from SSN substrates. Colonisation of discs by Staphylococcus aureus was the highest on GB [944 (± 91) × 104 CFU/mL], distinctly lower on experimental SN discs [414 (± 117) × 104 CFU/mL] and the lowest on SSN discs [307 (± 126) × 104 CFU/mL]. Primary human osteoblasts were abundant 28 d after seeding on GB discs but their adhesion and differentiation, measured by alkaline-phosphatase production, was suppressed by 73 % on SN and by 96 % on SSN discs, in comparison to GB discs. Thus, the PVD-applied Ag coatings differed considerably in their antibacterial effects and osteoconductivity. The experimental SN coating had similar antibacterial effects to the commercially available SSN coating while providing slightly improved osteoconductivity. Balancing the Ag content of Ti implants will be vital for future developments of implants designed for cementless fixation into bone.

scholarly journals Dependence of physical and mechanical properties of copper coatings on composition of chemical copper plating solution

2020 ◽  
Vol 62 (6) ◽  
pp. 65-73
Author(s):  
Ludmila A. Brusnitsina ◽  
◽  
Elena I. Stepanovskih ◽  
Tatiana A. Alekseeva ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Printed Circuit Boards ◽  
Thick Layer ◽  
Physical And Mechanical Properties ◽  
Copper Coating ◽  
Circuit Boards ◽  
Copper Plating ◽  
Metal Coatings ◽  
Printed Circuit ◽  
Copper Coatings

Chemical production of metal coatings is relevant and widely sought after. The field of practical use of chemical metal deposition reactions from aqueous solutions are continuously expanding. These reactions are widely used to obtain metal coatings for various purposes and begin to be used for the selective deposition of metals on a substrate in the form of patterns. Chemical copper plating has gained great practical importance. In additive and subtractive technology for the production of printed circuit boards, thick-layer chemical copper plating solutions are used to obtain a circuit diagram and metallization of holes. These are solutions that avoid the stage of galvanic copper plating, since the chemically deposited copper layer is sufficiently thick and allows further technological operations to be carried out. Chemical copper plating solutions must be stable, work with a sufficient copper plating rate and, most importantly, the resulting copper coatings have high physical and mechanical properties. This is due to the fact that during operation, printed circuit boards can be significantly heated, which leads to thermal expansion of both the board material and the copper coating. Due to the difference in the linear expansion coefficients of the substrate material and the deposited copper, significant stresses can occur in the copper layer deposited on the walls of the holes of the printed circuit board. When applying an inelastic copper coating, the layer breaks and the board exits the operating mode. This work is devoted to the study of the effect of some inorganic oxidizing agents on the properties of chemically precipitated copper, and this effect mainly affects the reduction of oxygen fragility. The mechanism of the process of chemical copper plating of a dielectric surface activated by palladium(II) salts is considered in detail. It is shown that at a high deposition rate of chemical copper, hydrogen is included in the coating, which leads to the appearance of “hydrogen” brittleness. Bubbling a solution of chemical copper plating with air increases the stability of the solution and can be used to oxidize certain forms of organic additives introduced into the solution to reduce hydrogen embrittlement. It is established that the incorporation of particles of copper oxide or hydroxide of monovalent copper into the copper coating leads to a decrease in the ductility of the copper coating and a decrease in the relative elongation of the chemically deposited copper layers. It was shown that in order to reduce the “oxygen” brittleness or increase the ductility of copper coatings, inorganic oxidants  ammonium persulfate and ferric sulfate salts must be introduced into the solution of chemical copper plating. Based on the experiments, it was found that in order to improve the ductility of the resulting copper coatings, ferric sulfate (Fe2(SO4)3∙9H2O) in the amount of 0.15-0.2 gl1. The conducted research cycle allowed us to recommend the following composition of a solution of thick-layer chemical copper plating, mol∙l–1: CuSO4 – 0.1; KNaTart – 0.21; NaOH – 0.375; Na2CO3 – 0.028; K3Fe(CN)6 – 3∙10–5; Fe2(SO4)3 – 3∙10–4; NiCl2 – 1.3∙10–2; ПАВ-2К – 0.1 g/l; formaldehyde – 25 mll1 40% solution. The solution is stable during operation, the coating deposition rate is from 3 to 4 μmh1, the plasticity of the resulting copper layers is 4-5%.

scholarly journals Nanostructured Silver Coating as a Stationary Phase for Capillary Gas Chromatography

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4491
Author(s):  
Qiong Jiang ◽  
Peng Xu ◽  
Juanjuan Feng ◽  
Min Sun
Keyword(s):  
Gas Chromatography ◽  
Stationary Phase ◽  
Retention Mechanism ◽  
Silver Coating ◽  
Dipole Interactions ◽  
Induced Dipole ◽  
Relative Standard ◽  
Different Types ◽  
Benzene Toluene ◽  
Silver Mirror Reaction

A capillary column coated with nanostructured silver coating was fabricated for gas chromatography. The nanostructured silver coating, about 80–120 nm in thickness, was prepared as the stationary phase via silver mirror reaction, and was characterized by SEM and EDS. The column was evaluated using different types of model analytes, including n-alkanes, n-alcohols, benzenes, and Grob mixture. A baseline separation of ten n-alkanes on the silver column (15 m × 0.20 mm i.d.) was achieved within 3.5 min through the main hydrophobic mechanism. A mixture of six n-alcohols, or another mixture containing three butanol isomers and two octanol isomers, was separated well on the column. The column separated some benzenes containing benzene, toluene, ethylbenzene, p-xylene, o-xylene, styrene, benzaldehyde, and benzyl alcohol. A Grob mixture containing seven analytes was also separated successfully. Based on a multiple retention mechanism such as hydrophobic, dipole-dipole, and dipole-induced dipole interactions, the silver column achieved a good separation of twelve different types of compounds within 2.5 min. The column presented satisfactory separation repeatability with relative standard deviation of retention time between 0.073% and 0.591%. The results indicate that the silver column is promising for gas chromatographic separation.

The extinction time of a general birth and death process with catastrophes

1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell
Keyword(s):  
Laplace Transform ◽  
Size Distribution ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Death Process ◽  
Extinction Time ◽  
Birth And Death Process ◽  
Different Types ◽  
The Laplace Transform ◽  
Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

Differentiating between different forms of moral obligations

2020 ◽  
Vol 43 ◽  
Author(s):  
Rajen A. Anderson ◽  
Benjamin C. Ruisch ◽  
David A. Pizarro
Keyword(s):  
Moral Character ◽  
Moral Obligations ◽  
Different Types

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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