Improvement of acid treatment with the sintanol preparation after hydro-sand blasting of wells in the conditions of ANK «Bashneft»

A sandblasting hammer is lowered into the well, setting against the selected processing interval, and hydraulic clamps are necessary for the rig to be held firmly. The displacement of the latter eliminates the possibility of selective processing. After the usual sandblasting and flushing the well from sand, without changing the position of the perforator, an acid solution is pumped into the pipes, which, entering the channel formed, is filtered through its walls into the treated section of the formation. The part of the acid that, after the end of the treatment, has accumulated in the wellbore, is forced into the reservoir by the squeezing fluid through the annular space. Increase the acid depletion time, i.e. slow down the reaction rate by adding special reagents to the solution. So, a syntanol DS-10 TU 2483-016-71150986-2012 (a non-ionic surfactant and is intended for use as an effective surfactant) is a very effective reaction rate reducer. Adding it in an amount of 0.5% (by weight of the volume of the solution) can reduce the reaction rate by 2.7 times. Keywords: speed; reaction; syntanol; processing; pressure.

Benefits of Residual Aluminum Oxide for Sand Blasting Titanium Dental Implants: Osseointegration and Bactericidal Effects

Objectives. The purpose of this work was to determine the influence of residual alumina after sand blasting treatment in titanium dental implants. This paper studied the effect of alumina on physico-chemical surface properties, such as: surface wettability, surface energy. Osseointegration and bacteria adhesion were determined in order to determine the effect of the abrasive particles. Materials and Methods. Three surfaces were studied: (1) as-received, (2) rough surface with residual alumina from sand blasting on the surface and (3) with the same roughness but without residual alumina. Roughness was determined by white light interferometer microscopy. Surface wettability was evaluated with a contact angle video-based system and the surface free energy by means of Owens and Wendt equation. Scanning electron microscopy equipped with microanalysis was used to study the morphology and determine the chemical composition of the surfaces. Bacteria (Lactobacillus salivarius and Streptococcus sanguinis) were cultured in each surface. In total, 110 dental implants were placed into the bone of eight minipigs in order to compare the osseointegration. The percentage of bone-to-implant contact was determined after 4 and 6 weeks of implantation with histometric analysis. Results. The surfaces with residual alumina presented a lower surface free energy than clean surfaces. The in vivo studies demonstrated that the residual alumina accelerated bone tissue growth at different implantation times, in relation to clean dental implants. In addition, residual alumina showed a bactericidal effect by decreasing the quantity of bacteria adhering to the titanium. Conclusions. It is possible to verify the benefits that the alumina (percentages around 8% in weight) produces on the surface of titanium dental implants. Clinical relevance. Clinicians should be aware of the benefits of sand-blasted alumina due to the physico-chemical surface changes demonstrated in in vivo tests.

Influence of the Agitation Pipe on the Flow Field of Electroplating Tank in the Electroplated Diamond Wire Saw

In order to solve the problem of diamonds sedimentation in electroplating tank and uneven distribution of diamonds in coatings, the fluid flow in the electroplating tank formed by three structure kinds of agitation pipe was compared and analysed. Results showed that the middle inlet type agitation pipe can significantly improve the fluid uniformity in the electroplating tank, and setting sand blasting ports at both ends of the agitation pipe can avoid the formation of fluid “dead zone”. Along the direction of the agitation pipe, the middle inlet type agitation pipe improves the overall flow of the fluid. In the position of the wire saw passing through, the difference of the speed in the electroplating tank of the middle inlet type is 47.17% and 15.25%, which is significantly lower than that of the water inlet structure of one end by 134.48%. As a result, it can significantly improve the plating effect of the wire saw.

The Effect of Different Surface Treatments on the Micromorphology and the Roughness of Four Dental CAD/CAM Lithium Silicate-Based Glass-Ceramics

Objective: This study aimed to investigate and compare the effect of various surface treatments on the micromorphology and the roughness of four CAD/CAM lithium silicate-based glass-ceramics (LSGC). Method: Eighty specimens of four LDGC materials (IPS e. max® CAD (Ivoclar-Vivadent, Liechtenstein, Schaan), Vita Suprinity® (Vita Zahnfabrik, Bad Säckingen, Germany), Celtra Duo® (Dentsply, Hanau-Wolfgang, Germany) and n!ce (Straumann, Basel, Switzerland)) were used for this study. All specimens were highly polished with 400, 600, 1200 grit silicon carbide paper and then polished with 3 µm and 1 µm polycrystalline diamond suspension liquid with grinding devices. Each group of ceramic was assigned to one of the following three surface treatments (1) sand-blasting (SB) with 50 µm Al2O3 at 70 psi for 10s, (2) hydrofluoric acid etching (HF) with 5% hydrofluoric acid, according to the manufacturer instructions, (3) and a combination of sand-blasting and hydrofluoric acid (SB + HF). All specimens were cleaned with ethanol for 2 min and placed in an ultrasonic unit with distilled water for 15 min. The microstructure was analyzed by scanning electron microscopy (SEM). The surface roughness and topography were evaluated with atomic force microscopy in tapping mode (AFM). Statistical analysis was done using two-way ANOVA and Tukey tests (α = 5%). Results: All surface treatments had a significant effect on LDGC surface roughness compared to the untreated surface (p < 0.05). The sand-blasting treatment had a significantly higher mean surface roughness value for Vita Suprinity and Celtra Duo compared to other surface treatments (p < 0.05). However, there was no significant difference for surface roughness between sand-blasting and sand-blasting + etching for e.max CAD and n!ce. The hydrofluoric acid produced less surface roughness compared to other surface treatments but was able to change the surface structure. (5) Conclusions: The sand-blasting + etching treatment could be a sufficient method to produce surface roughness for all LSGC types.

Surface Machining of Stainless Steel Cardiovascular Stents by Fluid Abrasive Machining and Electropolishing

The typical manufacturing process of tubular metallic cardiovascular stents includes laser cutting, sand blasting, acid pickling, electropolishing, surface passivation, and cleaning. The most commonly used material for cardiovascular stents is stainless steel, such as SUS 304 and SUS 316. After the laser cutting process, substantial improvement of the stent surface morphology is required to obtain acceptable surface roughness, edge roundness, and reduction of surface defects. This study focuses on a novel post-treatment method of fluid abrasive machining to replace the conventional sand blasting and acid pickling processes, resulting in the surface smoothness and edge roundness that are suitable for cardiovascular stent fabrication. The dross deposition and striations retained after laser cutting can be significantly removed with fluid abrasive machining. Both DC current and pulse current electropolishing techniques were performed to attain the final surface and structural quality after the fluid abrasive machining process. The experimental results show that an extremely fine surface roughness and a satisfactory edge roundness can be achieved for stents through both DC current and pulse current electropolishing. The pulse electropolishing process is more effective than the DC current electropolishing process to achieve edge roundness with less weight removal.

Eliminating Frequent Machine Assists through Process Plate Enhancement on Wirebonding Process

New devices and technologies in the semiconductor industry are getting more challenging to process because of inherent issues especially on quad-flat no-leads (QFN) packaging assembly. This paper is focused on the improvement done for QFN leadframe device to address the major machine assist during the lot processing at wirebond process. Illumination and visual of the leadframe and the sand blasting process plate on the machine are difficult to separately distinguish due to similar color shade of the materials, thus frequent machine assists ensued. To reduce the frequent machine assist occurrence, an improvement is done through enhancing the process plate by using a black chrome to totally separate the illumination of leadframe and the process plate. Ultimately, the machine assist during wirebonding process is improved (the longer the better) from 16 minutes to 6 hours continuous and uninterrupted running.

Sustainability Issues of Various Denim Washing Methods

Denim washing is increasingly joining the list of indispensable processes of meeting the demands of the world’s shifting fashion industry. Other than this, there is a rising trend in the sustainability perception among both producers and customers in the modern world. However, denim washing is considered to have direct impacts on the environment because of its chemical discharge and many other pollutants emitted during the process which affect water supplies. In the process, the denim industry encounters challenges at every level. Therefore, there is need for studying sustainable problems associated with denim washing. The unseen soul of the denim industry is technology, as nothing can be transformed without technological advancement. Sustainability problems of conventional washing have been addressed in this paper (i.e. pp spray washing, bleaching washing, stone washing, sand blasting etc.). Furthermore, the paper describes how sustainability can be achieved through the most recent washing techniques, such as laser, waterjet, nanobubble, ozone, NoStone, potassium permanganate alternatives etc. The introduction of new technologies has triggered a dramatic shift in the denim washing industry in terms of water usage, electricity and chemicals as well as improved quality. Consequently, it is undoubtful that the recent technologies in denim washing are crucial in making the industry sustainable. Moreover, the paper describes the idea of digitally printed denim and the available software for measuring sustainability in the process of denim washing.

Simulation of The Effect of Libyan Sand on The Reflectance Surface of CSP

The reflector characteristics are negatively affected by the harsh desert weather conditions and hence the performance of the system decreases. This paper investigates the effect of two different types of moving sands “A” and “B” from Libya on the performance and safety of the solar reflectors. Samples are collected from areas that are suitable for installing CSP plants. They are in different particle sizes and chemical compositions: sand “A” with size ranges between 0.025-0.355 mm, and “B” is within 0.124-0.479 mm. The experiment outcome using sand blasting indicated that sand “A” has more influence than sand “B” as thesmall particles of “A” spread over a large area of the reflector. It is also noticed in the range studied that the speed variation effect has more impact than the mass quantity changing. For clean surfaces, the reflectivity is dropped by 2.2%, and the damaged surfaces increased about 1 mm in case of 0.5 g mass at 27 m/s storm speed. For 2g mass at 21 m/s storm speed, the roughness is found 3 mm.

Selective Laser Melting Process of Al–Based Pyramidal Horns for the W-Band: Fabrication and Testing

In the context of exploring the possibility of using Al-powder Selective Laser Melting to fabricate horn antennas for astronomical applications at millimeter wavelengths, we describe the design, the fabrication, the mechanical characterization, and the electromagnetic performance of additive manufactured horn antennas for the W-band. Our aim, in particular, is to evaluate the performance impact of two basic kinds of surface post-processing (manual grinding and sand-blasting) to deal with the well-known issue of high surface roughness in 3D printed devices. We performed comparative tests of co-polar and cross-polar angular response across the whole W-band, assuming a commercially available rectangular horn antenna as a reference. Based on gain and directivity measurements of the manufactured samples, we find decibel-level detectable deviations from the behavior of the reference horn antenna, and marginal evidence of performance degradation at the top edge of the W-band. We conclude that both kinds of post-processing allow achieving good performance for the W-band, but the higher reliability and uniformity of the sand-blasting post-process encourage exploring similar techniques for further development of aluminum devices at these frequencies.