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The study aims to evaluate the corrosion behaviour of two steels: BL245 and S235JR, produced at Liberty Steel Galati. BL245 is an alloy used in the oil and gas industry to manufacture pipes for pipeline transportation systems. S235JR is used to make hot finished hollow sections for construction. Gasoline, diesel and a 3.5% sodium chloride solution were chosen as corrosion environments for this study, considering the field of use of the two alloys (oil and construction). Corrosion assessment was analysed using the gravimetric method, which is based on weighing the samples before and after they were immersed for 7, 14, and 35 days in the above-mentioned corrosion environments. Based on the initial weighing and those recorded after the immersion periods, the mass variation of the samples was determined, and the corrosion rate and penetration index were calculated.

The study aims to evaluate the corrosion behaviour of two steels: BL245 and S235JR, produced at Liberty Steel Galati. BL245 is an alloy used in the oil and gas industry to manufacture pipes for pipeline transportation systems. S235JR is used to make hot finished hollow sections for construction. Gasoline, diesel and a 3.5% sodium chloride solution were chosen as corrosion environments for this study, considering the field of use of the two alloys (oil and construction). Corrosion assessment was analysed using the gravimetric method, which is based on weighing the samples before and after they were immersed for 7, 14, and 35 days in the above-mentioned corrosion environments. Based on the initial weighing and those recorded after the immersion periods, the mass variation of the samples was determined, and the corrosion rate and penetration index were calculated. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solutions for safer, more durable infrastructure are required in light of increasing traffic and severe weather in Iraq. The most significant road conservation and maintenance challenges are the pavement's low resistance to dynamic loads and short service life. As a result, vast sums of money are spent annually to enhance the road service capacities in Iraq. Thermoplastic electrometric polymers for bitumen modification create long-lasting, cost-effective roadways. This study aims to determine how the mechanical properties of neat asphalt binder change when styrene butadiene styrene (SBS) is added as a modifier. The current research investigates adding three percentages of SBS (3, 5, and 7% of the weight of bitumen). Both neat and polymer-modified bitumen (PMB) were subjected to a series of physical laboratory and Superpave tests, including a dynamic shear rheometer tester (DSR) and a storage stability test. In addition, a chemical analysis test was conducted to identify any change in the neat binder chemical composition due to the addition of SBS polymer. The results indicated that 5% of SBS polymer was the optimum addition percentage to the local asphalt in Iraq. Additionally, it reduced the susceptibility of bitumen to temperature changes and enhanced its characteristics in all laboratory tests. The obtained PMB significantly improved rutting and fatigue factors compared to the neat asphalt binder. Based on the DSR tester and the storage stability test, the ratio of 5% SBS met the requirements of class PG76-10, used in the central and southern governorates of Iraq. Using SBS polymer on the surface course in Iraq reduces road damage due to the scorching summer sun, reduces the likelihood of rutting and fatigue cracking, and works well in hot regions, resulting in roads that last longer, provide comfortable riding, and require less maintenance.

One of the main hazards during tunnel boring machine (TBM) excavation in hard rock is related to the occurrence of unforeseen adverse conditions, leading to unfavourable rock mass behaviour during tunnel boring. In this respect, the continuous analyses of TBM excavation parameters may represent an interesting tool for a continuous monitoring of geotechnical conditions at the tunnel face and for early detection of changing ground conditions in the rock mass. This work provides a back‐analysis of TBM data recorded during the excavation of the Frejus Safety Tunnel, bored across the French‐Italian border in the Western Alps. It is a 13 km‐long tunnel excavated by a 9.4 m diameter, single‐shield TBM through strongly anisotropic calcareous schist, with cover up to 1800 m. Main problems faced during TBM excavation were related to the local occurrence of buckling‐related convergence and consequent asymmetrical loading on the precast segment rings. Correlating TBM performance parameters to the encountered geological and geomechanical conditions provides the possibility to identify which parameters are most affected by geomechanical properties of the rock mass at the tunnel face and by rock mass behaviour. Conversely, the analysis indicates which parameters can be adopted as monitoring tool of ground conditions during TBM advance. In addition, this work highlights how buckling phenomena can be distinguished, in terms of TBM operation and performance, from other adverse conditions as, e.g., blocky ground or squeezing. [ABSTRACT FROM AUTHOR]

Conventional hot mix plants operate to support large paving projects, making production more economic with high volume output. When repairs and maintenance are needed, it can be challenging to maintain small quantities of hot bituminous mixtures at a sufficient temperature, especially in the case of winter maintenance. Consequently, the repair materials cannot be compacted to the desired level on some occasions. This research aimed to develop a polymer modified asphalt binder with reduced temperature sensitivity for hand-laid and low-volume applications. The results showed that the highest penetration index has been achieved by modifying bitumen with 20% rubber and 2% wax. The FTIR and XRD analysis indicated that the bitumen, rubber and wax that react chemically to build 3D networks have an interlocked structure in the bitumen matrix resulting in reduced temperature sensitivity of the polymer modified asphalt binder. Furthermore, indirect tensile stiffness, permanent deformation, creep test and fatigue life test, water sensitivity and freeze-thaw cycle demonstrated an improvement in the asphalt mixture properties in terms of mechanical and durability perspectives. Overall, based on this investigation, modifying asphalt binder with 20% rubber and 2% wax resulted in stronger and durable asphalt mixture in comparison to traditional hot mix asphalt. [ABSTRACT FROM AUTHOR]

The performance of road pavement is strongly determined by material used in asphalt mixture. However, it is occasionally found that asphalt used in hot mix asphalt did not fulfill softening point requirement. On the other hand, the amounts of waste styrofoam and PVC are tend to increase and need a large space for its handling. Therefore, it is necessary to improve the quality of asphalt by using waste styrofoam and PVC. This article aims to review the performance of asphalt concrete using waste styrofoam and PVC as asphalt modifier based on the value of its penetration index. Styrofoam modified asphat was made by mixing asphalt penetration grade 60/70 with 0%, 2%, 4% and 6% waste styrofoam, meanwhile the percentages of waste PVC as asphalt modifier were 1%, 2%, 3% and 4%, respectively. The properties analyzed are Marshall stabiliy, flow, Marshall Quotient, Marshall immersion and retained strength index. From the analysis, it can be concluded that the use of waste styrofoam and PVC increase modified asphalt penetration index, and its penetration index significantly affect the properties of asphalt concrete

This study was done in order to evaluate the effect of a novel pressure pulsation device (Pulsehaler™, Respinova Ltd., Israel) on the deposition pattern of inhaled aerosol in the lungs of COPD patients. Fifteen COPD patients were recruited to undergo spirometry and SPECT-CT lung scan following nebulization of radioactively labeled albuterol in saline solution with a jet nebulizer ("NEB") and with a combined Pulsehaler™/jet nebulizer ("PH + NEB") treatment. Central and peripheral segments of the coronal and transverse SPECT scans were evaluated for total counts and for the ratios between peripheral counts and central counts (penetration Index, "PI"). There was a significant improvement in FEV1 from before to after albuterol treatment in the PH + NEB group (151 ml ± 187, p < 0.008), but not in the NEB only group (66 ml ± 125, p = 0.06). FVC, FEF25–75, FEV1%, FVC%, FEF25, FEF50, and FEF75 also improved significantly in the PH + NEB group but not the NEB group. There were significant improvements seen between treatments for FEF25-75 (PH + NEB > NEB, p = 0.0176), FEF75 (PH + NEB > NEB, p = 0.0028), but not for the other spirometry measures. Borg scores also were improved significantly improved in PH + NEB vs NEB (p = 0.0006). Total lung deposition and total body deposition were lower in the PH + NEB treatments vs the NEB treatments. However, PI values were 3.08 ± 0.67 times greater on average with the PH + NEB (p = 0.026) as compared to NEB only. The magnitude of the increased penetration index observed in this study indicates that pressure pulsations should be further explored as means to improve drug delivery into the distal small airways of the bronchial tree. Effects of the pressure pulsations on small airway patency could be the mechanism by which the effect was achieved. [ABSTRACT FROM AUTHOR]

This article presents paraffin oil mist penetration tests of commercially available air-purifying respirators of different construction conducted using the method described by Standard No. ISO 16900-3:2012, which incorporates flow rates (up to 255 l/min) of test aerosol. The testing method reflects differences in work intensity during the use of respirators. Moreover, the experimental stand, designed according to the international specifications, is described. The results show that the higher the paraffin oil mist flow rate, the higher the penetration index, irrespective of the testing method used and the type of respirator investigated. While at high flow rates, filtering half masks of the first protection class (FFP1) met the requirements of their protection class according to European Standard No. EN 149:20001+A1:2009, filtering half masks of the second and the third protection class (FFP2 and FFP3) did not. [ABSTRACT FROM AUTHOR]

Coir fibers (CFs) and micronized rubber powder (MRP) can be derived from low or negative-value agricultural/industrial waste streams and provide economical and sustainable pathways to develop high-value engineered products. This study investigated the influence of adding these modifiers on the performance characteristics of asphalt binders. Samples were produced using a mixture of slow-setting anionic asphalt emulsion with various quantities of MRP (at 0, 2 and 10 wt. %) and two levels of short CFs (~ 1 mm and 2 mm) with different fiber contents (at 0, 2 and 5 wt. %). The performance of modified asphalt samples was assessed by penetration depth (PD), softening point (SP), and penetration index (PI). Full factorial statistical design was structured to reveal the influence of main effects of the wt. % MRP, wt. % CFs, and CFs length and their interactions on the performance of the modified asphalt. Based on the statistical experimental design, linear regression analysis was performed. The linear regression showed that adding CFs and/or MRP consistently reduced PD, increased SP values and improved PI values. The length of CFs significantly affected the performance, which becomes more distinct with the increased weight content of CFs at 5 wt. %. It was also discovered that the combined addition of short CF and MRP achieved similar PI values at the same weight content of MRP alone. [ABSTRACT FROM AUTHOR]

The quality of asphalt pavement maintenance depends on several important factors, including the selection of patching materials and choice of repair technique. Conventional hot mix plants operate to support large paving projects, and economy favors high-volume output. When repairs and maintenance are needed it can be challenging to maintain small quantities of hot bituminous mixtures at a sufficient temperature, especially in the case of winter maintenance and consequently the repair materials cannot be compacted to the desired level in some occasions. The temperature sensitivity plays a significant factor to understand the asphalt pavement failures and indicates how quickly asphalt properties change over time in terms of indices such as penetration index. Therefore, this research aims to develop a polymer-modified binder with reduced temperature sensitivity, and it can be used for hand-laid application in small quantities for emergency winter repair and maintenance. The results showed that the highest penetration index has been achieved by modifying bitumen with 20% rubber and 2% wax, which is reduced the temperature sensitivity by 168%. Additionally, the Fourier Transform Infrared Spectroscopy (FTIR) test and X-Ray Diffraction (XRD) test were conducted to monitor the changes in the chemical composition and identify crystalline phases of polymer modified binder from the aspect of functional groups. It is indicated that the bitumen, rubber, and wax react chemically to build 3D networks that have an interlaced form in the bitumen matrix resulting in reduced temperature sensitivity of the polymer modified binder. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Evaluation of the adequacy of field compaction of granular soils, has always been a challenge for geotechnical engineers. The Lightweight Dynamic Cone Penetrometer (LDCP) has been established as one of the most versatile techniques, as it significantly reduces the required effort and cost. This research has been conducted to correlate the readings of LDCP laboratory tests, to compaction parameters of cohesionless soils. An experimental program has been performed on four different types of granular soils, at various compaction levels and moisture content values. The investigated soils included two sandy soils with different gradation and two different admixtures of sand with crushed dolomitic limestone. A series of LDCP and sand-cone tests have been conducted on soil samples which were compacted in a cubic steel mold, 60cm side length. The laboratory results have been integrated into a number of predictive correlations, which are capable of assessing the soil compaction parameters including; relative compaction, relative density, dry density and uniformity coefficient. Moreover, the compacted granular soils were found to be more sensitive to changes of moisture content from the optimum value, at lower ratios of relative compaction. [ABSTRACT FROM AUTHOR]

• In this study physical and rheological properties of modified binders are evaluated. • For evaluation of temperature susceptibilities of binders, three indices including Penetration Index (PI), Activation Energy (AE) and Viscosity-Temperature Susceptibility (VTS) are utilized. • Furthermore, for investigation of the modified and unmodified binders' structure, FTIR test is conducted. • Finally, the effect of different factors is statistically evaluated on the properties of modified binders. • To determine the significant parameters, analysis of variance (ANOVA) and Tukey statistical test are performed. This study investigated the effect of gilsonite and Styrene-Butadiene-Styrene (SBS) as asphalt binder modifiers on the physical and rheological properties of asphalt binders. For this, binder tests such as penetration test, softening point, rotational viscosity (RV), Dynamic Shear Rheometer (DSR), and Bending Beam Rheometer (BBR) were conducted on the neat and modified binders. The effect of gilsonite and SBS on the binder temperature susceptibility was also investigated by measuring Penetration Index (PI), Activation Energy (AE) and Viscosity-Temperature Susceptibility (VTS) of all the study binders. Fourier-Transform Infrared Spectroscopy (FTIR) test was directed toward investigation of the compositions' structure. The statistical analysis was also utilized to investigate the effect of gilsonite and SBS on the physical and rheological properties and temperature susceptibility of asphalt binders. The results indicated that incorporation of gilsonite and SBS to asphalt binder decreases the temperature susceptibility and improves mechanical and rheological properties of the asphalt binders. In addition, the results showed significant relationships between PI, AE and VTS with high temperature performance grade (HT) for almost all the modified binders. Results of Analysis of Variance (ANOVA) revealed that even though the binder modifier type has no significant effects on PI, AE, VTS, and viscosity, the modifier dosage can significantly affect these parameters. [ABSTRACT FROM AUTHOR]

The 50A and 70A asphalts produced by the same oil source have great differences in macroscopic properties. However, Fourier transform infrared spectra of 50A and 70A asphalts are almost identical with no differentiation in fingerprint region which offers great difficulty in bifurcation in chemical compositions of the two types of asphalts. To cope with these deficiencies, this study is aimed to investigate the composition and micro-performance of 50A and 70A asphalts via other unequivocal techniques including elemental analysis, scanning electron microscopy, fluorescence microscopy, X-ray diffraction analysis, gel permeation chromatography and nuclear magnetic resonance spectroscopy. Through these analyses, it was found that high temperature sensitive property, i.e., low penetration index of 50A asphalt was due to its higher contents of alkane moieties. Similarly, the dynamic viscosity of 50A asphalt was much higher than that of 70A asphalt due to larger relative molecular weight, high aromatic carbon contents and more aromatic rings in the former. This study systematically explained the reasons responsible for the differences in the macroscopic phenomena of different types of asphalts produced from the same oil source, which can establish a bridge between the macro-test results and microscopic properties of asphalt and hence can best analyze asphalt produced from the same oil source resulting in collection of broader and diverse information. [ABSTRACT FROM AUTHOR]

Cellulose microfibrils (CMFs) and micronized rubber powder (MRP) can be derived from low or negative-cost agricultural/industrial waste streams and offer environment-friendly and cost-effective pathways to develop engineering products. This study investigated the efficacy of adding these micromodifiers on the performance characteristics of asphalt binders. In this work, samples were produced using a mixture of slow-setting anionic asphalt emulsion with various combinations of MRP (at 0, 2 and 10 wt %) and four types of CMFs (hydrophobic and hydrophilic with crystalline ratios of 86% and 95%) at 0, 2 and 5 wt %. The performance of modified asphalt samples was assessed by penetration depth (PD), softening point (SP), and penetration index (PI). Linear regression analysis showed that adding CMFs and/or MRP reduced PD and increased SP values. The type of CMFs significantly affected the performance, which becomes more distinct with the increased weight content of CMFs. While hydrophilic CMFs caused increases in SP and PI values, no clear trend was seen to determine the effect of CMF crystallinity. It was also discovered that the combined addition of CMF and MRP achieved similar PI values at lower total weight content compared to using MRP alone.

Tunnel boring machine (TBM) is the preferred method in the construction of long-distance and deep-buried tunnel due to its advantages in safety and high efficiency. However, the TBM method is very sensitive to the condition of the surrounding rock. The strength and integrity characteristics of rock mass have great influence on the safe and efficient tunnelling. To provide a fast perception method for these characteristics during the TBM tunnelling process, an in-situ penetration testing system is proposed in the present study. The development and testing procedure of the system are elaborated. The system is applied to a TBM-excavated water conveyance tunnel to continuously perceive the strength and integrity characteristics of the surrounding rock. Firstly, the force-penetration (F-P) responses of the surrounding rock under penetration are qualitatively studied. Then, series of penetration indices are summarized to quantify the characteristics of the F-P responses. Finally, the quantitative relationships between the rock strength and the penetration indices are studied. The results indicate that the in-situ penetration testing system can perceive the rock mass strength and integrity characteristics qualitatively and quantitatively. On the qualitative aspect, the F-P responses can be categorized into four types (Type I to Type IV), which correspond to the level of rock mass strength and integrity. On the quantitative aspect, a single penetration index cannot represent the complete information of the F-P response. The descriptive classification of the rock mass strength (class I to III) is established through multiple penetration indices. The in-situ penetration testing system can be used as a method to quickly perceive the strength and integrity characteristics of the surrounding rock in TBM tunnelling. [ABSTRACT FROM AUTHOR]

Ground moisture content and strength properties are the most important factors for a proper assessment of ground stability. This study developed a dynamic cone penetrometer incorporated with time domain reflectometry (TDR) sensors (TDCP). The TDCP is composed of an anvil, a driving rod, and a TDCP probe. Three wave guides and a K-type thermocouple are installed on the TDCP probe. For utilization of TDCP, relationships between relative permittivities measured by TDCP and those measured by standard TDR probe, temperature, and volumetric water content of the soils were investigated. In addition, the relationship between penetration indices by TDCP (TPI) and by standard dynamic cone penetrometer was established. In the field application test, relative permittivity, ground temperature, and TPI were measured along the depth. Moreover, gravimetric water contents were also measured for comparison. The experimental results showed that volumetric water contents compensated by ground temperature showed good agreement with the volumetric water contents estimated from the gravimetric water contents of the soil samples and TPI. This study suggests that the TDCP may be effectively used for the evaluation moisture contents and for the strength characterization of the subsurface.

Pemeriksaan dilakukan dengan cara mengumpulkan data dari serangkaian pengujian karakteristik aspal. Kemudian dilakukan analisis dan pembahasan. Pengambilan abu TKKS didapat dari TKKS yang baru diambil dan dibakar menjadi abu yang lolos saringan #200. Dalam pemeriksaan dilakukan dengan empat tahap. Tahap I untuk mencari karakteristik aspal 60/70. Tahap II untuk mencari kadar aspal optimum pada aspal 60/70. Tahap II untuk mencari kadar abu TKKS optimum dengan variasi kadar abu TKKS 0,0%, 1,0%, 2,0%, 3,0%, dan 4,0% terhadap kadar aspal optimum, sehingga didapat kadar abu TKKS optimum 1,5% terhadap kadar aspal optimum. Tahap III dilakukan pengujian penetrasi dan titik lembek aspal dengan penambahan abu TKKS kadar optimum sebesar 1,5% untuk mendapatkan nilai penetration index (PI). Tahap IV yaitu menganalisis nilai PI tanpa penambahan abu TKKS dan dengan penambahan abu TKKS. Sehingga dari hasil PI didapat abu TKKS bisa dimanfaatkan sebagai bahan tambah untuk campuran beton aspal walaupun mengalami penurunan nilai durabilitas namun masih dalam batas yang ditentukan ≥75% ini disebabkan karena pada pengujian penetrasi dan titik lembek aspal dengan penambahan abu TKKS kadar optimum mengalami penuruan yang menandakan aspal tersebut menjadi keras dan rentan terhadap perubahan temperatur karena abu TKKS banyak mengandung K2O yang bersifat mudah teroksidasi dan peka terhadap perubahan temperatur.

With respect to the physical and mechanical limited qualities of bitumen, it benefits from certain specificability in application and its life service. Polymers as the most important modifiers of bitumen are applied to it in order to improve its functional efficiency. Among various polymers, styrene-butadiene- styrene (SBS) is the best modifier of the bitumen. In this work, SBS polymer as one of the modifiers of elastomeric thermoplastics with different weight percentages (2% to 5%) have been mixed with bitumen (60/70) of Isfahan Refinary and its effect on different properties of the bitumen for example penetration index, softening point, Frass breaking point and reduction in weight perecentagehas been studied. Furthermore, in this paper, the modified bitumen property on performance grade is the preferred category. Classification of modified bitumen based on performance grade makes it possible to provide perfect bitumen pattern in different climates.

Ethylene copolymer bitumen (ECB), namely Lucobit, as a thermoplastic polymer, SBS as a thermoplastic-elastomer polymer, and ethylene-vinyl-acetate (EVA) combined with Fischer-Tropsch wax and resin additives, namely Rheofalt WKR-2, as a modified thermoplastic polymer were used for stone matrix asphalt modification. Two types of asphalt modification processes including polymer-modified bitumen (PMB) and direct addition of polymer into mixture were employed and the effect of each one on resilient modulus and rutting resistance was evaluated by performing Indirect Tensile Resilient Modulus and Hamburg Wheel Tracking tests. PMB, SBS, and Rheofalt-modified mixtures resulted in lower rut depth and higher resilient modulus than did those modified by ECB. In direct addition of the polymer into mixture process, there is reduction in rutting resistance and resilient modulus of Rheofalt-modified mixtures in comparison with PMB. Furthermore, there was no improvement for ECB-modified mixtures by direct addition modification. [ABSTRACT FROM AUTHOR]

The article reports on the efficiency of raise boring machine for excavation of passage in mining and civil engineering fields. Topics mentioned include the bore machine performance measurement, the underground mine management, and the tensile strength of boring machine. Also mentioned are the tunnel boring machines cutting rate and the testing of excavation machine.

• Portable testing device is required for characterization of slope ground. • Instrumented dynamic cone penetrometer incorporated with TDR (IDPT) was developed. • The results of IDPT test are consistent with existing devices. • IDPT can profile the ground strength and volumetric water content with the time. • IDPT may be effectively used to characterize the ground strength and water content. In this study, an instrumented dynamic cone penetrometer incorporated with time domain reflectometry (IDPT) is developed to provide portable in-situ penetrometer for evaluation of ground strength and water content. The IDPT probe combines cone tip energy module with accelerometer and load cell, and time domain reflectometry (TDR) probe to simultaneously obtain transferred energy and water content. The IDPT is applied to embankment with dynamic cone penetrometer (DCP) and penetrometer incorporated with TDR probe (TDRP). In addition, the strength and water content of ground in rainfall conditions are characterized with time. Penetration indices of IDPT and DCP show similar trends in ground strength characterization, and volumetric water contents detected by IDPT and TDRP are almost identical. As water infiltrates the ground with time, the penetration index and volumetric water content increase. This study suggests that the IDPT may be effectively used for the simultaneous evaluation of ground strength and water content. [ABSTRACT FROM AUTHOR]

Unmodified and modified bitumen were evaluated by determination of softening point, penetration and dynamic viscosity. Bitumen was modified by crumb rubber. Properties of modified and unmodified bitumen were compared. The effectiveness of bitumen modification is reflected in properties change of the prepared mixture in comparison to the properties of unmodified bitumen. Determination of penetration and softening point gives possibility of calculation of the temperature susceptibility and penetration index of unmodified and modified bitumen. Softening point, penetration, penetration index, viscosity and relative viscosity increment were investigated as the performance criteria for evaluation of bitumen modified by crumb rubber. Results showed that the values of viscosity and relative viscosity increment are the most suitable for modifier effectiveness evaluation. [ABSTRACT FROM AUTHOR]

It is shown that the introduction of inorganic inhibitors, such as sodium nitrate and sodium tungstate in fast-hardening bitumen-latex compositions does not affect the time of hardening of the obtained coating and almost does not change the penetration, ductility, and softening temperature. The anticorrosion properties of bitumen-latex coatings are improved as a result of the addition of 0.4 g/liter of sodium nitrate and sodium tungstate to their composition. After 39 days of testing in a hydraulic chamber ( t = 30°C; 3% NaCl spray), we did not observe the formation of pittings on the steel substrate and the adhesion of the coating to the surface changed insignificantly. [ABSTRACT FROM AUTHOR]

The present work has the purpose of studying metallographic aspects and corrosion resistance of three materials used in ammonia stripping plants. The corrosion process was evaluated by gravimetric tests and potentiodynamic method. Materials tested were Al 1050 (99.5%Al), stainless steel AISI 316Ti and low alloy steel P235TR2. To determine gravimetrically the rate of penetration, samples were immersed in corrosive environment for 294 days and weighed periodically. As test solution 0.5 M ammonium hydroxide (specific for coke industry) was used in a three electrode open cell with material tested as working electrode (WE), a platinum electrode as counter electrode (CE) and an Ag/AgCl electrode as reference electrode (RE).

The occurrence of bitumen deposits in Nigeria has been estimated to be about 42 billion tones; almost twice the amount of existing reserves of crude petroleum" Nigerian Investment Promotion Commission (NIPC).For proper planning of extraction techniques for heavy crude oil such as Nigeria bitumen or oil sand, softening point is a paramount parameter need to be estimated for determining the temperatures at which bitumen will melt and when the slug start to flow into production systems. The softening point (SP) and penetration index (PI) of bitumen from parts of south-western Nigeria are important properties needed for better design and optimization of the upgrading process of Nigerian bitumen. This study was carried out to design a cost effective and efficient softening point tester to classify bitumen into grades using jatropha oil as fluid bath instead of water. Jatropha oil has higher specific heat capacity and dissipates heat faster than water. It takes shorter time to heat and soften a sample of bitumen compares to water. This saves time and cost as energy generation cost less. Use of Jatropha as bath fluid in the areas of processing bitumen would assist the operator to achieve higher output, less heat for softening and produces a higher softening point. [ABSTRACT FROM AUTHOR]