Production of Bitumen Modified with Low-Molecular Organic Compounds from Petroleum Residues. 3. Tar Modified with Formaldehyde

The chemical modification of tar with formaldehyde as 37% aqueous solutionhas been studied in the presence of the catalysts. Hydrochloric acid, sulfuric acid, sodium hydroxide and acid tar were used as the catalysts. The effect of the catalyst nature and amount, as well as temperature, process time and initial components ratio on the softening point, penetration, brittle point and adhesion to crushed stone has been determined. The structure of the modified tars was confirmed by IR spectroscopy. The structural-group composition was determined. Arene-formaldehyde resins have been synthesized on the basis of toluene and modified tars using hydrochloric acid as a catalyst. The synthesized resins were characterized using IR spectroscopy. The chemistry of the tar modification with formaldehyde has been proposed.

Improvement of Low-Temperature Performance of Buton Rock Asphalt Composite Modified Asphalt by Adding Styrene-Butadiene Rubber

To improve the low-temperature performance of the Buton rock asphalt (BRA)-modified asphalt, styrene-butadiene rubber (SBR) was added to it. The BRA-modified asphalt and SBR-BRA composite modified asphalt were prepared by high-speed shearing method. The penetration, softening point, ductility, and Brookfield viscosity of the two kinds of asphalt were measured. The dynamic shear rheometer (DSR) and the beam bending rheometer (BBR) were employed to research the performance of BRA-modified asphalt by adding SBR. The results showed that the pure asphalt in BRA was the main reason to reduce the low-temperature performance of neat asphalt when the content of BRA was 19%. However, the ash in BRA was the main factor to reduce the low-temperature performance when its content was more than 39.8%. When the BRA content was 59.8%, the SBR-BRA composite modified asphalt with SBR contents of 2%, 4%, 6%, and 8%, and it shows that the penetration and ductility of the BRA-modified asphalt are increased by the addition of SBR. The equivalent brittle point was reduced, the stiffness modulus was decreased, and the creep rate was increased. At the same time, the Brookfield viscosity was reduced and the rutting factor was increased. The stiffness modulus of the SBR-BRA composite modified asphalt mixture was increased. That is to say, when SBR was mixed into the BRA-modified asphalt, the low-temperature performance could be remarkably improved based on ensuring high-temperature performance. The low-temperature index of composite modified asphalt was analyzed. It was recommended to apply the equivalent brittle point to evaluate the low-temperature performance of SBR-BRA composite modified asphalt.

Rubber Mixes: Experience in Database Development

The ‘Rubber mixes’ program package has been developed on the basis of Microsoft Access 2010. Its functional possibilities are as follows: (1) the search for a specific grade to look up all the characteristics of the rubber mix; (2) the search for a specific specification (TU) or other documentation to look up the composition of the TU, and also the properties of the mixes contained in the TU (depending on the classification adopted in the TU, there are two types of form – according to rubber type or according to rubber mix designation); (3) a comparative analysis of rubber mixes with respect to a single property; (4) the search for a rubber mix with several prescribed parameters, for example: the type of rubber, the working medium and the temperature range, the tensile strength, the elongation at break, the hardness, the cold resistance coefficient, and the brittle point; (5) the formation of different reports. A brief description is given of developed forms. The creation within the industry of a Unified Classifier of Rubber Mix Use Designations is proposed.

Researches on Brittle Seam Mining Based Situation Assessment and Prediction Mechanism of DDoS Attacks in Cloud Computing Platform

According to the problem of Situation Assessment and Prediction of DDoS Attacks in Cloud Computing Platform, the concepts of Brittle Point and Brittle seam were introduced to describe the situation of an eco-system according to ranked node availability, and a Situation Assessment and Prediction Mechanism based on the Brittle Seam Mining Algorithm was proposed. In the Brittle Seam Mining Algorithm, biological features of DDoS attacks and cloud computing platform were analyzed from the point of bio-dynamics, and the analysis results indicate that bandwidth loads of the normal user access from different populations wound not reach the brittle point of an eco-system, while bandwidth load of victim under DDOS attacks will reach the brittle point. The Biological Invasions Model such as the population diffusion reaction model and the population reproduction model are adopted to predict and detect the Brittle Point and Brittle seam. Meanwhile, the GIS technology was used in the visualization of Brittle seam. The simulation results verify the applicability of this method.

Research on Enzymatic Hydrolysis Lignin Modified Petroleum Asphalt

In this paper, a series of enzymatic hydrolysis lignin modified petroleum asphalts were prepared. The physical properties such as softening point, ductility at low temperature and penetration of the modified asphalt were investigated. The penetration index of asphalt modified with EHL was higher than that of unmodified asphalt, equivalent softening point increased and equivalent brittle point decreased with the increase of EHL amount, which showed that the addition of EHL was favorable to reduce the temperature susceptivity of asphalt. When the EHL was 4%, the ductility was 39.0 cm. Meanwhile, low temperature performance of asphalt could be further improved by adding EHL and a small amount of SBS.