Shielding Effect of Aluminium, aganist Cs-137 gamma source, according to Transmission Technique

Sea level and wave data at Salalah coast (Oman) were used to simulate nearshore waves and current during the tropical cyclone ARB01 (9 May2002). STWAVE model (Steady State Spectral Wave) was applied for nearshore wave simulation, while M2D model ((Two-Dimensional Depth Averaged circulation model) was used to simulate nearshore current. The results of simulations (taking into account the mutual effects of both current and waves) showed that: The significant wave heights generally decrease from about 6m at the domain boundary to about 1 m close to the coast. The wave heights during the ebb period were higher than that during the flood period by about 1.5m. Along Salalah coast, higher waves were found along the eastern side of the domain. This is because the shielding effect of breakwater, which protect the western part of the coast from high waves. Relatively Strong current with values up to 1.5 ms-1 were found in the nearshore region during both ebb and flood periods. The M2D model results also showed cyclonic circulations during these periods which help in the renewal of harbor waters. Generally, the model results showed good agreements with observations in the investigated area.

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Correlation of the diamond/matrix interphase zone structure with tool efficiency obtained by technology combining diamonds metallization with matrix sintering

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2018-94-2-111-123 ◽

2019 ◽

pp. 111-123 ◽

Cited By ~ 1

Author(s):

P. P. Sharin ◽

M. P. Akimova ◽

V. I. Popov

Keyword(s):

Thermal Diffusion ◽

Shielding Effect ◽

Specific Productivity ◽

Grinding Wheel ◽

Zone Structure ◽

Chromium Powder ◽

Carbide Matrix ◽

Diffusion Metallization ◽

Effect Of Copper ◽

Diamond Retention

The paper studies structure and phase characteristics of the interphase zone diamond/matrix in dressers made by thermal diffusion metallization of a diamond combined with matrix sintering based on WC–Co and Cu impregnation. The compact arrangement of chromium powder particles around diamond grains and the shielding effect of copper foil create favorable conditions for thermal diffusion metallization of diamond at matrix sintering. A metallized coating chemically bonded with diamond and consisting of chromium carbide and solid solution of cobalt in chromium phases provides a strong diamond retention in the carbide matrix. It was shown that it is formed on the surface of the diamond under the conditions specified in the experiment and the temperature – time sintering mode. The specific productivity of experimental dresser made by hybrid technology at straightening green silicon carbide grinding wheel equaled 51.50 cm3/mg exceeding that of the control dresser made without metallization of diamonds by sintering with copper impregnation by 44.66%.

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1H NMR Conformational Studies in Water of Angiotensin II Analogues Modified at the N- and C-Termini: Interactions of the Aromatic Side Chains and Folding of the N-Terminal Domain

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19942523 ◽

1994 ◽

Vol 59 (11) ◽

pp. 2523-2532 ◽

Cited By ~ 4

Author(s):

John Hondrelis ◽

John Matsoukas ◽

George Agelis ◽

Paul Cordopatis ◽

Ning Zhou ◽

...

Keyword(s):

Shielding Effect ◽

Resonance Spectroscopy ◽

Nmr Studies ◽

Previous Suggestion ◽

Aminoisobutyric Acid ◽

H Nmr ◽

Neutral Ph ◽

Angiotensin Ii Analogues ◽

Proton Resonances ◽

Cosy Nmr

The conformation of [Sar1]angiotensin II in water at neutral pH has been examined by proton magnetic resonance spectroscopy at 400 MHz and in particular by comparing its 1H NMR spectral data with those of analogues modified at positions 1,4 and 6, namely [Sar1,Cha8]ANGII, [Des Asp1,Cha8]ANGII, [Aib1,Tyr(Me)4]ANGII, [Aib1,Tyr(Me)4,Ile8]ANGII, [N-MeAib1,Tyr(Me)4]ANGII, [N-MeAib1,Tyr(Me)4,Ile8]ANGII, ANGIII and [Sar1,Ile8]ANGII. Assignment of all proton resonances in these analogues was made possible by 2D COSY NMR experiments. The H-2 and H-4 protons for the histidine ring in [Sar1]ANGII, ANGII and ANGIII were shielded compared with the same protons in [Sar1,Ile8]ANGII, [Sar1,Cha8]ANGII and [Des Asp1,Cha8]ANGII; this shielding effect was not disturbed upon methylation of the tyrosine hydroxyl and/or replacement of residue 1 (sarcosine or aspartic acid) with aminoisobutyric acid (Aib) or N-methyl aminoisobutyric acid (N-MeAib). These data are consistent with our previous suggestion based on NMR studies in neutral DMSO that a characteristic folded conformation for ANGII previously observed in non-polar solvents can also be detected in water at neutral pH, but to a lesser degree.

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The Additive Influence of Propane-1,2-Diol on SDS Micellar Structure and Properties

Molecules ◽

10.3390/molecules26123773 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3773

Author(s):

Martina Gudelj ◽

Paola Šurina ◽

Lucija Jurko ◽

Ante Prkić ◽

Perica Bošković

Keyword(s):

Mixed Solvents ◽

Sodium Dodecyl ◽

Shielding Effect ◽

Bulk Solution ◽

Structure And Properties ◽

Micellar Structure ◽

Related Substances ◽

Micellar Systems ◽

Small Change ◽

Additive Influence

Micellar systems are colloids with significant properties for pharmaceutical and food applications. They can be used to formulate thermodynamically stable mixtures to solubilize hydrophobic food-related substances. Furthermore, micellar formation is a complex process in which a variety of intermolecular interactions determine the course of formation and most important are the hydrophobic and hydrophilic interactions between surfactant–solvent and solvent–solvent. Glycols are organic compounds that belong to the group of alcohols. Among them, propane-1,2-diol (PG) is a substance commonly used as a food additive or ingredient in many cosmetic and hygiene products. The nature of the additive influences the micellar structure and properties of sodium dodecyl sulfate (SDS). When increasing the mass fraction of propane-1,2-diol in binary mixtures, the c.m.c. values decrease because propane-1,2-diol is a polar solvent, which gives it the ability to form hydrogen bonds, decreasing the cohesivity of water and reducing the dielectric constant of the aqueous phase. The values of ΔGm0 are negative in all mixed solvents according to the reduction in solvophobic interactions and increase in electrostatic interaction. With the rising concentration of cosolvent, the equilibrium between cosolvent in bulk solution and in the formed micelles is on the side of micelles, leading to the formation of micelles at a lower concentration with a small change in micellar size. According to the 1H NMR, with the addition of propylene glycol, there is a slight shift of SDS peaks towards lower ppm regions in comparison to the D2O peak. The shift is more evident with the increase in the amount of added propane-1,2-diol in comparison to the NMR spectra of pure SDS. Addition of propane-1,2-diol causes the upfield shift of the protons associated with hydrophilic groups, causing the shielding effect. This signifies that the alcohol is linked with the polar head groups of SDS due to its proximity to the SDS molecules.

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Corrosion Protection of Q235 Steel Using Epoxy Coatings Loaded with Calcium Carbonate Microparticles Modified by Sodium Lignosulfonate in Simulated Concrete Pore Solutions

Materials ◽

10.3390/ma14081982 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1982

Author(s):

Weilin Liu ◽

Jiansan Li ◽

Xiangqi Huang ◽

Jinye Bi

Keyword(s):

Calcium Carbonate ◽

Corrosion Inhibitor ◽

Aqueous Media ◽

Mechanical Tests ◽

Attenuated Total Reflection ◽

Shielding Effect ◽

Sodium Lignosulfonate ◽

Epoxy Coatings ◽

Pencil Hardness ◽

Q235 Steel

In this study, calcium carbonate (CaCO3) microparticles having pH-sensitive properties were loaded with sodium lignosulfonate (SLS), a corrosion inhibitor. Scanning electron microscope (SEM), UV–VIS spectrophotometer (UV-vis), X-ray diffraction (XRD), and attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR) were applied to evaluate the properties of the synthetic microparticles. This material could lead to the release of corrosion inhibitor under different pH conditions of the aqueous media. However, the extent of release of the corrosion inhibitor in the acidic media was higher, leading to enhanced shielding effect of the Q235 steel. These microparticles can serve as anti-corrosion additive for epoxy resin-coated Q235 steel. Electrochemical experiments were used to assess the anti-corrosive ability of the epoxy coatings in simulated concrete pore (SCP) solution, confirming the superior corrosion inhibition of the epoxy coating via incorporation of 5 wt % calcium carbonate microparticles loaded with SLS (SLS/CaCO3). The physical properties of coating specimens were characterized by water absorption, contact angle, adhesion, and pencil hardness mechanical tests.

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Photoprotection of Arabidopsis leaves under short-term high light treatment: the antioxidant capacity is more important than the anthocyanin shielding effect

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2021.06.006 ◽

2021 ◽

Author(s):

Zheng-Chao Yu ◽

Xiao-Ting Zheng ◽

Wei Lin ◽

Wei He ◽

Ling Shao ◽

...

Keyword(s):

Antioxidant Capacity ◽

Light Treatment ◽

High Light ◽

Shielding Effect ◽

Short Term ◽

High Light Treatment

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Complex Geometry Strain Sensors Based on 3D Printed Nanocomposites: Spring, Three-Column Device and Footstep-Sensing Platform

Nanomaterials ◽

10.3390/nano11051106 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1106

Author(s):

Alejandro Cortés ◽

Xoan F. Sánchez-Romate ◽

Alberto Jiménez-Suárez ◽

Mónica Campo ◽

Ali Esmaeili ◽

...

Keyword(s):

Carbon Nanotubes ◽

3D Printing ◽

Complex Geometry ◽

Uv Light ◽

Shielding Effect ◽

Strain Sensitivity ◽

Printing Technology ◽

3D Printing Technology ◽

Sensing Platform ◽

Electromechanical Performance

Electromechanical sensing devices, based on resins doped with carbon nanotubes, were developed by digital light processing (DLP) 3D printing technology in order to increase design freedom and identify new future and innovative applications. The analysis of electromechanical properties was carried out on specific sensors manufactured by DLP 3D printing technology with complex geometries: a spring, a three-column device and a footstep-sensing platform based on the three-column device. All of them show a great sensitivity of the measured electrical resistance to the applied load and high cyclic reproducibility, demonstrating their versatility and applicability to be implemented in numerous items in our daily lives or in industrial devices. Different types of carbon nanotubes—single-walled, double-walled and multi-walled CNTs (SWCNTs, DWCNTs, MWCNTs)—were used to evaluate the effect of their morphology on electrical and electromechanical performance. SWCNT- and DWCNT-doped nanocomposites presented a higher Tg compared with MWCNT-doped nanocomposites due to a lower UV light shielding effect. This phenomenon also justifies the decrease of nanocomposite Tg with the increase of CNT content in every case. The electromechanical analysis reveals that SWCNT- and DWCNT-doped nanocomposites show a higher electromechanical performance than nanocomposites doped with MWCNTs, with a slight increment of strain sensitivity in tensile conditions, but also a significant strain sensitivity gain at bending conditions.

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Design of Customize Interbody Fusion Cages of Ti64ELI with Gradient Porosity by Selective Laser Melting Process

Micromachines ◽

10.3390/mi12030307 ◽

2021 ◽

Vol 12 (3) ◽

pp. 307

Author(s):

Cheng-Tang Pan ◽

Che-Hsin Lin ◽

Ya-Kang Huang ◽

Jason S. C. Jang ◽

Hsuan-Kai Lin ◽

...

Keyword(s):

Stress Concentration ◽

Selective Laser Melting ◽

Stress Shielding ◽

Simulation Software ◽

Surrounding Tissue ◽

Shielding Effect ◽

Stress And Strain ◽

Laser Melting ◽

Flexion Extension ◽

Intervertebral Cage

Intervertebral fusion surgery for spinal trauma, degeneration, and deformity correction is a major vertebral reconstruction operation. For most cages, the stiffness of the cage is high enough to cause stress concentration, leading to a stress shielding effect between the vertebral bones and the cages. The stress shielding effect affects the outcome after the reconstruction surgery, easily causing damage and leading to a higher risk of reoperation. A porous structure for the spinal fusion cage can effectively reduce the stiffness to obtain more comparative strength for the surrounding tissue. In this study, an intervertebral cage with a porous gradation structure was designed for Ti64ELI alloy powders bonded by the selective laser melting (SLM) process. The medical imaging software InVesalius and 3D surface reconstruction software Geomagic Studio 12 (Raindrop Geomagic Inc., Morrisville, NC, USA) were utilized to establish the vertebra model, and ANSYS Workbench 16 (Ansys Inc, Canonsburg, PA, USA) simulation software was used to simulate the stress and strain of the motions including vertical body-weighted compression, flexion, extension, lateral bending, and rotation. The intervertebral cage with a hollow cylinder had porosity values of 80–70–60–70–80% (from center to both top side and bottom side) and had porosity values of 60–70–80 (from outside to inside). In addition, according to the contact areas between the vertebras and cages, the shape of the cages can be custom-designed. The cages underwent fatigue tests by following ASTM F2077-17. Then, mechanical property simulations of the cages were conducted for a comparison with the commercially available cages from three companies: Zimmer (Zimmer Biomet Holdings, Inc., Warsaw, IN, USA), Ulrich (Germany), and B. Braun (Germany). The results show that the stress and strain distribution of the cages are consistent with the ones of human bone, and show a uniform stress distribution, which can reduce stress concentration.

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