Laboratory Assessment of Asphalt Binders Containing Petroleum Resin

2021 ◽  
Author(s):  
Navid Hemmati ◽  
Hyunhwan Kim ◽  
Mithil Mazumder ◽  
Soon-Jae Lee ◽  
Moon-Sup Lee
Keyword(s):  
Asphalt Binders ◽  
Laboratory Assessment ◽  
Petroleum Resin

scholarly journals Laboratory Characterization of Asphalt Binders Modified with Styrene Butadiene Rubber (SBR)

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7666
Author(s):  
Navid Hemmati ◽  
Jihyeon Yun ◽  
Mithil Mazumder ◽  
Moon-Sup Lee ◽  
Soon-Jae Lee
Keyword(s):  
Asphalt Binders ◽  
Styrene Butadiene Rubber ◽  
Creep Recovery ◽  
Butadiene Rubber ◽  
Laboratory Assessment ◽  
Rotational Viscometer ◽  
Viscosity Property ◽  
Modified Binders ◽  
Modified Binder ◽  
Styrene Butadiene

The study describes the laboratory assessment (physical and rheological properties) of the binders (PG 64-22 and PG 76-22) modified with Styrene Butadiene Rubber (SBR), and a comprehensive comparison between these two modified binder types. PG 64-22 and PG 76-22 were used as base binders. Both of the base binders were blended with SBR at four different percentages of content (0%, 4%, 6%, and 8% by the weight of the binder). The base and modified binders were artificially short-term and long-term aged using a rolling thin film oven (RTFO) and pressure aging vessel (PAV) procedures. Superpave binder tests were conducted on the SBR modified binder using rotational viscometer (RV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR). In depth rutting performance was investigated using Multiple Stress Creep Recovery (MSCR). The results of this study indicated that (1) the addition of SBR into both binders increased the viscosity and polymer modified asphalt (PMA) binders observed to have more significant effect on its viscosity property; (2) the higher the SBR content, the better the rutting resistance of the binder and it is observed that the effect is prominent on the control binder; (3) MSCR test results showed that the SBR modified binders improved the binder percentage recovery and found to have a more significant effect on the PG 76-22 binder compared to PG 64-22; and (4) both the control PG 64-22 and PMA PG 76-22 binders resulted in similar trends on the cracking properties and were found to have insignificant effects due to the addition of an SBR modifier.

POSTOPERATIVE COMPLIANCE OF BARIATRIC SURGERY PATIENTS REGARDING THE ASSESSMENT OF SERUM LEPTIN LEVELS AND INSULIN RESISTANCE

2019 ◽  
Vol 49 (1/2019) ◽  
Keyword(s):  
Insulin Resistance ◽  
Bariatric Surgery ◽  
Serum Levels ◽  
Medical Laboratory ◽  
Leptin Resistance ◽  
Obese Patients ◽  
Laboratory Assessment ◽  
Serum Leptin ◽  
Before And After ◽  
Bariatric Patients

Background and aims: Overweight and obese patients who undergo bariatric surgery require a rigorous clinical and paraclinical assessment both before and after the surgery at 3, 6, and 12 months.The present study aims the assessment of serum leptin levels and insulin resistance status in compliant bariatric patients to scheduled medical laboratory assessment at 6 months after surgery. Material and Method: The study included 109 eligible patients selected for bariatric surgery, 48 of whom attended the scheduled visit at 6 months after the surgery. Laboratory assessing regarded the insulin resistance by determining before meal the serum levels of leptin, glucose and insulin, as well as HOMA 1 and HOMA 2 indexes. Results: Patients who underwent bariatric treatment experienced a significant decrease in insulin resistance status. A higher percentage in the preoperative group was recorded in women, feature which was also recorded in the postoperative group that attended the scheduled visit at 6 months after surgery. Age is also an important factor that significantly influences the behavioral adherence to postoperative visits. Conclusions: Insulin resistance status improved significantly in 6 months after bariatric surgery among the fully compliant patients. The percentage of attendance at scheduled visits is higher among women, and decreases with age. Keywords: obesity surgery, leptin resistance, insulin resistance, HOMA index, compliance

Process of Producing Hard Sized Paper by Using Petroleum Resin Surface Sizing Agent

1964 ◽  
Vol 18 (4) ◽  
pp. 161-168
Author(s):  
Ten Yoshii ◽  
Shigehiko Yoshioka ◽  
Keisaburo Tabuchi
Keyword(s):  
Petroleum Resin ◽  
Surface Sizing

scholarly journals Classic Ketogenic Diet and Modified Atkins Diet in SLC2A1 Positive and Negative Patients with Suspected GLUT1 Deficiency Syndrome: A Single Center Analysis of 18 Cases

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 840
Author(s):  
Jana Ruiz Herrero ◽  
Elvira Cañedo Villarroya ◽  
Luis González Gutiérrez-Solana ◽  
Beatriz García Alcolea ◽  
Begoña Gómez Fernández ◽  
...  
Keyword(s):  
Movement Disorder ◽  
Glucose Transporter ◽  
Deficiency Syndrome ◽  
Laboratory Assessment ◽  
Modified Atkins Diet ◽  
Atkins Diet ◽  
Glut1 Deficiency ◽  
Glut1 Deficiency Syndrome ◽  
The Impact

Background: Glucose transporter type 1 deficiency syndrome (GLUT1DS) is caused by mutations in the SLC2A1 gene and produces seizures, neurodevelopmental impairment, and movement disorders. Ketogenic dietary therapies (KDT) are the gold standard treatment. Similar symptoms may appear in SLC2A1 negative patients. The purpose is to evaluate the effectiveness of KDT in children with GLUT1DS suspected SLC2A1 (+) and (-), side effects (SE), and the impact on patients nutritional status. Methods: An observational descriptive study was conducted to describe 18 children (January 2009–August 2020). SLC2A1 analysis, seizures, movement disorder, anti-epileptic drugs (AEDS), anthropometry, SE, and laboratory assessment were monitored baseline and at 3, 6, 12, and 24 months after the onset of KDT. Results: 6/18 were SLC2A1(+) and 13/18 had seizures. In these groups, the age for debut of symptoms was higher. The mean time from debut to KDT onset was higher in SLC2A1(+). The modified Atkins diet (MAD) was used in 12 (5 SLC2A1(+)). Movement disorder improved (4/5), and a reduction in seizures >50% compared to baseline was achieved in more than half of the epileptic children throughout the follow-up. No differences in effectiveness were found according to the type of KDT. Early SE occurred in 33%. Long-term SE occurred in 10, 5, 7, and 5 children throughout the follow-up. The most frequent SE were constipation, hypercalciuria, and hyperlipidaemia. No differences in growth were found according to the SLC2A1 mutation or type of KDT. Conclusions: CKD and MAD were effective for SLC2A1 positive and negative patients in our cohort. SE were frequent, but mild. Permanent monitoring should be made to identify SE and nutritional deficits.

scholarly journals Material Properties and Environmental Benefits of Hot-Mix Asphalt Mixes Including Local Crumb Rubber Obtained from Scrap Tires

Environments ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 47
Author(s):  
Lim Min Khiong ◽  
Md. Safiuddin ◽  
Mohammad Abdul Mannan ◽  
Resdiansyah
Keyword(s):  
Asphalt Binder ◽  
Crumb Rubber ◽  
Environmental Benefits ◽  
Asphalt Binders ◽  
Rubber Content ◽  
Scrap Tires ◽  
Asphalt Mixes ◽  
Temperature Resistance ◽  
Modified Asphalt ◽  
Marshall Stability

This paper presents the results of a laboratory-based experimental investigation on the properties of asphalt binder and hot-mix asphalt (HMA) mixes modified by locally available crumb rubber, which was used as a partial replacement of asphalt by weight. In this study, fine crumb rubber with a particle size in the range of 0.3–0.6 mm, obtained from scrap tires, was added to the asphalt binder through the wet process. Crumb rubber contents of 5%, 10%, 15%, and 19% by weight of asphalt were added to the virgin binder in order to prepare the modified asphalt binder samples, while the unmodified asphalt binder was used as the control sample. The crumb rubber modified binder samples were examined for measuring viscosity indirectly using the penetration test, and temperature resistance using the softening point test. Later, both the modified and unmodified asphalt binders were used to produce HMA mixes. Two categories of HMA mix commonly used in Malaysia—namely, AC 14 (dense-graded) and SMA 14 (gap-graded)—were produced using the modified asphalt binders containing 5%, 10%, 15%, and 19% crumb rubber. Two AC 14 and SMA 14 control mixes were also produced, incorporating the unmodified asphalt binder (0% crumb rubber). All of the AC 14 and SMA 14 asphalt mixes were examined in order to determine their volumetric properties, such as bulk density, voids in total mix (VTM), voids in mineral aggregate (VMA), and voids filled with asphalt (VFA). In addition, the Marshall stability, Marshall flow, and stiffness of all of the AC 14 and SMA 14 mixes were determined. Test results indicated that the modified asphalt binders possessed higher viscosity and temperature resistance than the unmodified asphalt binder. The viscosity and temperature resistance of the asphalt binders increased with the increase in their crumb rubber content. The increased crumb rubber content also led to improvements in the volumetric properties (bulk density, VTM, VMA, and VFA) of the AC 14 and SMA 14 mixes. In addition, the performance characteristics of the AC 14 and SMA 14 mixes—such as Marshall stability, Marshall flow, and stiffness—increased with the increase in crumb rubber content. However, the AC 14 mixes performed much better than the SMA 14 mixes. The overall research findings suggest that crumb rubber can be used to produce durable and sustainable HMA mixes, with manifold environmental benefits, for use in flexible pavements carrying the heavy traffic load of highways.

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