Advanced Materials Research Vol. 773

Abstract: In this paper, experimental results on the in situ concrete strength have been reported in order to suggest some possible improvements of the current investigation planning strategies. The results of experimental campaign carried out on existing structures are discussed in order to investigate the variability of Destructive Tests (DTs) and Non Destructive Tests (NDTs). Then, the characteristics of the most usual procedures (core testing, rebound number, ultrasonic pulse, ...) have been examined. The results showed primarily the unsuitability (thus its uselessness) of the rebound test in order to describe the variability of concrete characteristics inside the buildings. On this basis, an alternative procedure has been suggested to obtain in-situ concrete strength.

Abstract: The manganese sulfate solution leached from low-grade pyrolusite with pyrite and H₂SO₄ contains heavy metal ions of high concentration, influencing the quality of the final products of manganese compounds and causing manganese ions not to be electrolyzed. The present study was focused on the separation of Co, Ni and Zn ions from the leached solution with BaS. By controlling the pH value at 5.0-6.5, temperature at 50-60°C, reaction time at 15 min and mixing velocity at 78 rpm, the heavy metal ions could be separated effectively. Under the above optimized conditions, the ion concentration of Co, Ni, and Zn in the solution was reduced to 0.06 mg.L^-1, 0.27mg.L^-1 and 0.01mg.L^-1, and the separation efficiency was 99.72%, 99.18% and 99.9% respectively. The obtained pure solution meets the demands of manganese electrowinning.

Abstract: In this paper, using Nissan car engine oil as the research object, their main physical and chemical performances and three factors of oil carrying capacity such as the maximum non-seizure load P_B, sintering load P_D and the composite wear value ZMZ are experimental analyzed in different mileage. And decay law of the lubrication performances are discussed. It was found that, after used a certain time, the oils film strength reduced relatively fast, the limit ability to work reduced not obvious, and its anti-extrusion capability will gradually deteriorate with the increase in the running time.

Abstract: During recent years, the Taiwan government launches issues of green building , sustainable engineering , carbon reduction and etc. , to promote balance construction and environment ecology. One of the most important materials in those engineering issues is cement which is used widely in construction industry. Cement emits 0.85 tons of carbon dioxide (CO₂) for each ton of cement used in average. This not only causes the waste of energy but also againsts the conception of environmental protection. This research uses the rice husk ash (RHA) which people always regards as the waste material as a pozzolanic material to replace part of cement to make high performance concrete (HPC). Then makes the value analysis and properties investigation for HPC. Based on this research, rice husk (RH) will contain lots of silicon dioxide (SiO₂) after burning into RHA. If use RHA to replace part of cement, it can get appropriate properties of compressive strength and durability. More important is that by replacing part of cement, it not only will reduce the emission of CO₂ and save money but also reach the goal of global village protection on earth.

Abstract: Aquathermolysis reaction of heavy oils occurring in high temperature water environment significantly degrades the heavy components of heavy oils, improves oil quality and reduces its viscosity. Aerosol, oil-soluble, and water-soluble nickel catalysts obviously and effectively catalyze the aquathermolysis reaction of heavy oils in a high temperature and reduces its viscosity, producing a gas increase of 49%, 41% and 21% respectively compared with the result with the absence of any catalyst. An aerosol, oil-soluble and water-soluble nickel catalyst compound (best quality ratio 1:1:2) increases the oil recovery of heavy oils by 8.5% and decreases the viscosity of sample oil and average relative molecular mass of porous media by 89.6% and 23% respectively, with its resin and asphaltene content significantly reduced. The pilot field tests show that, the test cycle production of heavy oils of each well proves an increase of 81.2 ~ 226.1t (not considering the cycle decline rate) over the previous one, which means that the field tests coincide with the laboratory experiments.

Abstract: In this paper, sulfuric acid leaching of copper slag at atmospheric pressure was used to produce copper sulfate solution and higher leaching ratio of copper sulfate solution was obtained. Meanwhile, some factors (Acid concentration, the temperature, the liquid-solid ratio, time and other) were investigated and analyzed in the production process. In addition, this work provided smelting plants with economically viable technology of copper recovery process from copper slag.

Abstract: In this paper, a 3D elastic-plastic and coupled thermo-mechanical FE model of radial ring rolling of 6061 aluminum alloy is developed, and the hot rolling process with different the rotational speed of driver roll n is simulated by using the dynamic explicit code ABAQUS/Explicit. The influence laws of the rotational speed of driver roll on the uniformity of strain and temperature distribution (STD), fishtail coefficient, roll force, contact area and roll moment are revealed respectively. One optimum n is obtained, under which SDT is relatively uniform; meanwhile, another optimum n is obtained, under which the quality of end-plane of the rolled ring is the best. The result can provide a valuable guideline to research and optimum of the hot ring rolling of aluminum alloys.

Abstract: Conjugated linoleic acid (CLA) was prepared by alkali isomerization using walnut oil as raw materials, KOH as catalyst and propylene glycol as solvent. The kinetics of alkali isomerization of linoleic acid from walnut oil converted into CLA was experimentally studied under the reaction conditions of 393~453 K,and which the initial mass ratio of propylene glycol, walnut oil and KOH was 3:2:1. The mechanism of alkali isomerization was proposed, and the mechanism model was put forward through theoretical derivation.The rate constants were determined, the mechanism model was verified,and the kinetics parameters were obtained.The results showed that alkali isomerization reaction was first order the concentration of linoleic acid, which the apparent activation energy was 67.22 kJ·mol^-1 and the pre-exponential constant was 8.963×10⁵min^-1.

Abstract: In this investigation, the bioleaching of potassium, silicon and aluminum from natural illite by three strains of Paenibacillus polymyxa , Agrobacterium tumefaciens and Penicillium heteromorphum purchased from China General Microbiological Culture Collection Center was studied. Chemical analyzing investigation indicated that K₂O , SiO₂ and Al₂O₃ were major chemical components. Bioleaching tests were performed in an orbital shaker with 250mL conical flasks at 30°C and 200 r/min agitation. The results show that, In the whole bioleaching process, the maximum extracts of K₂O , SiO₂ and Al₂O₃ are 1.96, 7.96 and 4.57 g/L respectively with Paenibacillus polymyxa, 1.73, 6.9 and 4.19 g/L with Agrobacterium tumefaciens, and 1.68, 6.23 and 7.12 g/L with Penicillium heteromorphum. Paenibacillus polymyxa is the most efficient of releasing K and Si, the most efficient of releasing Al is the strain of Penicillium heteromorphum.

Abstract: This study compared nitrite scavenging of apple polyphenols extracted from Fuji apple, yellow banana apple and red banana apple in simulated gastric conditions. Scavenging rates of peel and pulp polyphenols from single and mixed solutions from different varieties were studied. The results showed that: 1 In the same extraction process, which was ultrasonic treatment for 15min, the solid-liquid ratio 1:4 and ethanol volume fraction 60%, contents of polyphenols in red banana apple were significantly higher than that in other apples both in peel and pulp. 2 In simulated gastric conditions, nitrite scavenging of red apple pulp polyphenols increased with increasing concentrations, and it reached 90.9% at concentration of 100μg/mL. 3 At the concentration of 100μg/mL, nitrite scavenging of banana apple was significantly higher than that of Fuji apple, and pulp higher than peel in banana apple. 4 Nitrite scavenging of mixed apple polyphenols was lower than that of single solutions. Over all, apple polyphenols have a strong nitrite scavenging effect, and nitrite scavenging of banana apple was higher than that of Fuji apple.