bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Carbon-Thermal Reaction Mechanism of Potassium feldspar and Phosphogypsum
Authors: Yang Chao Qin , Xia Ju Pei
Published: December 2014

This paper has proved that best material ratio is n (KAlSi3O8) : n (CaSO4) : n (C) = 2:7:3 in carbon-thermal reduction of potash feldspar and phosphogypsum for preparation potassium sulfate, which is based on thermodynamic calculation and analysis, combined with experimental study. XRD analysis shows that generated solid content is K2SO4, CaSiO3 and Ca2Al2SiO7 at the batching system. Under the above ingredients system, the production ways of potassium sulfate have three possible. It depends on operating temperature of the system. At the same time, the phosphogypsum reduction conditions and decomposition rate is controlling factor that potassium sulfate is generated in the system.
Protection of Laborers Occupational Safety Rights from the Perspective of Human Rights Law
Authors: Lu Fang Hua
Published: December 2014

As a basic human right, occupational safety rights have already drew attention all over the world. A series of significant law system, such as the labor law, safety production law, law of Prevention and Control of Occupational Diseases etc, involve the protection of occupational safety rights. But as a member of the International Labor Organization, protecting system for the occupational safety rights in China face a series of problems, such as coverage narrow, low damages, weak awareness of human rights protection, lack of systemic laws and regulations. Thus, it needs to be perfected by speeding up legislation process for occupational safety rights protection, enhancing the enforcement of law, stable labor relations, creating a favorable environment for market economy development in China. Besides, on the point of the force of law, we should optimize the operability of the occupational safety rights protection legislation system from the labor law, safety production law, law of Prevention and Control of Occupational Diseases.
Assessment of Economic Losses on Agricultural Non-Point Source Pollution by Abuse of Fertilizer in Manasi River Basin of China
Authors: Cheng Zhong Hai , Luo Fang
Published: December 2014

Agricultural Non-point Source (AgNPS) pollution is one of the most important reasons for environmental pollution and unbalance of ecology. Nowadays, the negative impact of AgNPS pollution is increasing. Oasis and desertification exist at the same time in Xinjiang. The evaluation of economic loss caused by AgNPS pollution was carried out in the Manasi River Basin. The economic losses on AgNPS pollution were assessed by the methods of Concentration-Value Curve. Fertilizer overusing were focused on this research,which were major sources of AgNPS pollution. The results showed that environment economic loss caused by abuse of fertilizer was 8.115 million RMB in 2012.
Optimization Monitoring Points of Urban Road Traffic Noise in Binzhou City
Authors: Zhao Fu Guo
Published: December 2014

Considering the Impact of the current urban road traffic noise,I optimize the traffic noise monitoring points on the basis of the actual measurement data. The experimental results prove that less monitoring points may reflect the overall traffic noise level in Binzhou City.
Research on Environmental Master Factors Discrimination of Sea Area in Tianjin Port
Authors: Yu Hang
Published: December 2014

Incremental tendency method is used to discriminate master factors of regional environmental quality. In this article, incremental tendency method has been revised. Taken Tianjinport sea area as an example, the collation of environmental quality master factors in 2012 has been listed. It is advanced that environmental quality master factors of Tianjin port sea area are mainly inorganic nitrogen and petroleum substances, and pollution management should also be aimed at these types of substances. Finally the meaning of new model in application has been explained. It provided practical basis for sustainable development of Tianjin sea area protection.
Analysis of Discharge Characteristics of Typical Rural Domestic Wastewater along the Tuojiang River
Authors: Li Bin , Yang Ji Fu , Zhou Yun , Chen Jun Min
Published: December 2014

Environmental pollution caused by rural domestic wastewater has become increasingly serious. However, data on the current characteristics of rural domestic wastewater are scarce. In this study, we selected typical villages along the Tuojiang River as study objects. We analyzed the pollution status and discharge characteristics of rural domestic wastewater along the Tuojiang River through field research in winter and summer. Data analysis and collection, as well as water monitoring, were performed to determine the water quality and quantity characteristics of the rural domestic wastewater. The per capita daily discharges of rural domestic wastewater along the Tuojiang River are 11.26–50.37 L in winter and 18.39–303.57 L in summer. Both the maximum and average concentrations of pollutants in the rural domestic wastewater are higher than those in urban domestic wastewater, but the per capita daily discharge of pollutants is clearly lower in rural areas than in urban areas. The analysis of the typical discharges of rural domestic wastewater along the Tuojiang River provides a valuable reference for rural wastewater discharge treatment planning and process selection.
The Investigation of Biosensor for Tetrodotoxin Monitoring
Authors: Chen Jing , Yang Zhuo
Published: December 2014

Using Bacillus licheniformis as identify element, and it was immobilized by sandwich immobilization, a biosensor was fabricated based on oxygen electrode. The experiment indicated that the appropriate pH range is 7.76, the optimum temperature is 35±0.5 °C, and the appropriate concentration of GGA is 21.5 mg/L in bottom fluid, toxicity sensor of biosensor based on Bacillus licheniformis has a linear response from 10 to 80 μg/L and the standary curve is y=0.0026x-0.01, its linear correlation is 0.9669. The immobilization membrane produced by Bacillus licheniformi save more than 40 days, and measured 3 ~ 4d for activation, the performance of the system is stable.
An Approach and Case Study on Determination of the Sulfur Deposition Radius in High Sulfur Gas Reservoir
Authors: Luo Pei , Luo Yu Ming , Ma Kai , Zhang Biao , Song Sha Sha
Published: December 2014

In the process of high sulfur gas field development, the sulfur will separate out from the mixed gas when the pressure near wellbore area drops to a critical pressure of H2S. This will reduce the reservoir porosity greatly and decrease the gas well productivity as well. This paper discusses the characteristics of pressure transient testing plots when sulfur deposition occurs based on the redial composite reservoir model. And introduce an approach to determine the sulfur deposition radius near the wellbore with pressure transient testing interpretation in high sulfur gas reservoir. The method has been applied in some high sulfur gas field in eastern Sichuan Basin. The result shows that the method is simple and practical.
How Inoculation with Arbuscular Mycorrhizal Fungi Impact on Soil Respiration?
Authors: Ma Fang , Zhang Shu Juan , Wang Li , Shan Dan , Jiang Xiao Feng , Zhang Xue , Li Zhe
Published: December 2014

Soil respiration can be altered by changing substance supply, respiratory capacity and the demand for the products. We carried out a field experiment in the northeast of China to understand how inoculation with arbuscular mycorrhizal fungi (AMF) alters soil respiration in paddy fields. Soil respiration and factors contributing to it were measured for paddy fields either inoculated or non-inoculated with AMF, with or without fertilization. We found that inoculation increased soil respiration, net photosynthesis of rice leaves, N and P content of rice shoots and the abundance of actinomyces and fungi in rhizosphere; while the negative effect was only observed on root biomass. We also found that fertilization decreased the responses of soil respiration, root biomass and the abundance of bacteria and fungi in rhizosphere to inoculation. However, it decreased the responses of net photosynthesis, shoot biomass and shoot N and P content to inoculation. Conclusively, AMF inoculation promoted soil respiration by enhancing substrate supply, respiratory capacity and the demand for products; while the impacts of inoculation were weakened by fertilization via respiration capacity and the demand for the products.
Effects of Aridity and Salinization on Soil Microbial Biomass C in a Desert Ecosystem
Authors: Guan Hai Ying , Zhao Xin
Published: December 2014

In this study, we measured soil microbial biomass C (SMBC) under four different land cover types (canopy, litter, lichen and bare soil) to determine the effects of aridity and salinization on SMBC of a typical desert ecosystem. Results showed that higher SMBC with lower soil salt content and higher soil moisture were found in general if with vegetation, and the SMBC under canopy was especially higher than any other land cover types, which was near double of that of bare soil (115.34μg C g-1 soil vs. 61.88μg C g-1 soil). Linear regression analysis indicated that soil SMBC were positively correlated (p<0.01,r =0.899) with soil moisture but negatively correlated (r =-0.784, p<0.01) with soil salt content. These relationships may represent an evolutionary process, aiding in the conservation of essential vegetation in a fragile desert ecosystem.
Spatial Distribution and Assessment of Soil Heavy Metals in Rural Dumpsite of North China
Authors: Yan Hong  Xia , Ma Jun Wei , Liu Yan Zhong , Ren Yu Qing
Published: December 2014

Soil samples from 6 sampling sites along 5 depths (0, 10, 20, 30, 40cm) were collected from an rural dumpsite in Hebei Province. The heavy metal (As, Cr, Cd, Pb, Cu, Zn) concentration were measured by inductively coupled plasma atomic absorption spectrometry (ICP/AES) in order to study the spatial distribution and assess their risk by the geoaccumulation index and potential ecological risk index. It was found that the mean concentrations of Cd, Pb, Cu were higher than the elemental background values in Hebei Province. The spatial distribution show that the longer stacking area had heavier heavy metal pollution in deeper soil due to long-term penetration of leachate and new stacking area had heavier pollution in surface soil. However, the geoaccumulation index and potential ecological risk index values show that most sites of the studied soils is in uncontaminated or low contaminated level. The potential ecological risk index values in the dumpsite were, in descending order, Cd > Cu > Pb > As > Cr > Zn, respectively, implying that Cd, Cu, Pb posed a higher hazard to human and ecosystem health. It was recommended that some measures were required to reduce heavy metal contents in soils caused by garbage dump.
Comparative Analysis of Nitrate Removal in Sub-Surface Flow Constructed Wetlands by Different External Carbon Sources
Authors: Awhavbera Patience , Zhao Lian Fang
Published: December 2014

External carbon sources provide additional nutrients that improve the efficiency of nitrate removal in constructed wetlands. Typha angustifolia L. were planted in four vertical subsurface-flow constructed wetlands. Different external carbon sources were fed into the columns, to investigate and compare their treatment of nitrate in synthetic wastewater, with initial influent C/N ratio of 1:1. Wetland A (WA) with 50g wheat straw as external carbon source, wetland B (WB) with 50g woodchips, wetland C (WC) with additional 10mg/L glucose and wetland D (WD) without external carbon source to serve as the control, were used in the lab-scale experimental study. WA, WB, WC and WD within a period of 24 days, cumulatively removed 109.38mg/L, 93.75mg/L, 85.14mg/L, and 64.01mg/L nitrate, respectively, from the influent. The nitrate-nitrogen (NO3–N) removal efficiency as aided by the external carbon sources was in the order: wheat straw > woodchips > glucose > control. Wheat straw treated 93% NO3–N, woodchips 78%, glucose 72% and the control 53%. The results indicate that WA, WB and WC outperformed the control system, due to the additional carbon sources. In general, the wheat straw had a better performance than wood chips and glucose. Thus, wheat straw as low cost biological waste product is recommended for the treatment of nitrate in wetlands.
Preliminary Study of Photosynthetic Bacteria Treating Hydrothermal Liquefaction Wastewater
Authors: Yuan Guo Yang , Lu Hai Feng , Huang Shi Wei , Zhang Yuan Hui , Li Bao Ming , Zhang Ting Ting
Published: December 2014

Post hydrothermal liquefaction wastewater (PHWW) was generated during biocrude oil production. It contains lots of carbon, nitrogen and phosphorous elements, which can cause environmental pollution and resource waste. Using photosynthetic bacteria (PSB) to treat this kind of wastewater can realize pollutants elimination and resource recovery. In this work, the feasibility of using PSB to treat PHWW was firstly investigated, and the treatment conditions were optimized. Results showed that the PSB can effectively degrade PHWW. The optimal initial COD concentration, inoculum size and light intensity for PSB to treat PHWW were 6000-10000 mg/L, 50 mg/L and 1000-3500 lux, respectively. With the initial COD concentration of 9000 mg/L, inoculum size of 50 mg/L and light intensity of 1000 lux, the COD, NH3-N, TP removal and biomass production reached to 71%, 90%, 47.2% and 773 mg/L, respectively. This showed that using PSB to treat PHWW can be an alternative method for PHWW nutrients recovery and pollutant treatment.
The Development of the Water-Saving and Haze-Preventing Integrated System on Gantry Crane
Authors: Yao Zhen Nan , Zheng Yang
Published: December 2014

With the frequent appearance of haze weather, haze-preventing has become one of the serious environmental problems. Among all measures, preventing inhalable particulate matter from the source is one of the most effective ways to eliminate haze. Based on the traditional water mist dust suppression technology, this paper developed a water-saving integrated system, by exploiting PROFIBUS-DP to connect water mist dust suppression system to gantry crane in port. This integrated system was demonstrated accurately spraying water mist while the crane dropping down coal. In this way, the suspended particulate matter is successfully inhibited, while fresh water is saved.
Research on Synergic Governance for Air Pollutants Emission of Thermal Power Sector in China
Authors: Cui Shu Yin
Published: December 2014

The current governance for air pollutants presents problems, such as the singleness of administration body，slack law enforcement of the environment protection departments and the ineffective coordination among the different departments. The synergy governance can mobilize the plural stakeholders to participate in a joint effort to improve the air quality. The paper analyzes the status of governance for air pollutants in China. Also, based on flue gas desulphurization (FGD) franchise pilot project in the thermal power plant, the paper summarizes the connotation of franchise and progresses made in flue gas desulphurization. Finally, the mode of synergic governance for air pollutants emission is presented.
Adsorption of Ni(II) from Aqueous Solution by Sulfuric Acid and Thermally Treated Attapulgite
Authors: Ren Jun , Song Xiao Wei , Xu Dan , Gou Dong Dong , Tao Ling
Published: December 2014

Adsorption of Ni (II) onto modified attapulgite was investigated with respect to temperature, initial concentration and contact time. The kinetics data related to the adsorption of nickel from aqueous solutions were in good agreement with the pseudo-second order equation in ranges of initial concentration of 20-200 mg/L, and temperature of 298-328K.The thermodynamic experiment results showed that the equilibrium adsorption isotherm was closely fitted with the Langmuir model. Enthalpy change (△H0), entropy change (△S0) and Gibbs free energy change (△G0) were calculated from the temperature dependent sorption data, and the results indicated that the sorption of Ni (II) on modified attapulgite was a spontaneous process, and the sorption was endothermic.
Performance Evaluation of the Horizontal Subsurface Flow Constructed Wetland with Ipomoea Aquatica Plant for Rural Domestic Wastewater Treatment
Authors: Osman Ahmed Mohammed , Lu Xi Wu
Published: December 2014

In this study, the performance treatment of horizontal subsurface flow constructed wetland (HSFCW) was evaluated. The HSFCW built as a tertiary treatment process after the biological reactors to improve the effluent quality. The HSFCW system was operated with different hydraulic loading rates (HLRs) ranged from 0.15 to 0.333 m3/ (m2.d) to assess their influence on removal efficiency. During the system operation time, the average temperature was ranged of 22.3 to 31.2 °C and pH ranges was 7.3 – 8.1. The Ipomoea aquatica (Chinese spinach) planted into HSFCW system and the growth parameters during the experimental operation observed. The Ipomoea aquatica growth parameters such as the plant height, a fresh and dry weights were monitored and measured. The influent and effluent of chemical oxygen demand (COD), ammonium nitrogen (NH4-N), total nitrogen (TN) and total phosphorus (TP) were examined. The removal efficiency for all parameters showed decreased with an increase in HLR from 0.15 to 0.333 m3/ (m2.day). The results demonstrated that the average removal efficiency of the COD, NH4-N, TN and TP during system operation is 52.9%, 64.6%, 58.2% and 72.8% respectively. These results confirm that the HSFCW has a good efficient in treatment and can be used for the nutrients and organic matter removal from the domestic wastewater.
The Thermo-Gravimetric Characteristics of the Waste Game Printed Circuit Board under Different Atmosphere
Authors: Feng Rong , Wang Bo
Published: December 2014

The printed circuit board (PCB) in the electronic waste contains a variety of metals and organic materials, including bromine, heavy metals and other pollutants. Thermal treatment is an effective method for harmless disposal of waste circuit boards with resources recycle. In this study, the composition of RF4 type waste game PCB was determined by elemental analysis and proximate analysis, followed by thermogravimetric analysis of the weight lost process in CO2、N2or air, at 10°C/min, 20°C/min or 30°C/min programmable heating rate, and the thermal decomposition reaction kinetics parameters were calculated with the Kissinger method. The results show that under the CO2atmosphere, the weight loss process of the sample consists of the 250°C～410°C and 750°C~960°C temperature intervals; under the N2atmosphere, the rapid weight loss stage is between 263°C and 420°C; under the air atmosphere, the weight loss process is from 178°C to 675°C, including three minor weight loss stages. The phenolic volatile components are mainly released around 260°C～360°C under three different atmospheres, while the residual carbon is further oxidized under the air atmosphere or gasified in CO2at temperatures above 800°C.
Research on Treatment Organic Waste Liquid of High Concentration Acid by Cavitation Impinging - Micro Electrolytic Method
Authors: Li Fu Bao , Li Xiao Bai , Wu Hao , Xiao Shu Yi
Published: December 2014

The high concentration and high acid organic waste liquid is treated by using the self-developed drum type cavitation impinging stream—micro electrolysis reactor. Under optimal conditions, namely iron-carbon ratio of 1: 1, each reaction time 3h, standing reflux for 2 times, first filler dosage 200g, successive half, controlling the pH value of less than 3. Waste liquid COD removal rate can reach 93.5%, and the biodegradability of the effluent B/C is more than or equal to 0.4. By comparing the treatment effect of cavitation impinging assisted and simple micro electrolysis, it is founded that COD removal rate is high by using cavitation impinging assisted micro electrolysis method the processing time is short, the water is good biodegradability lower production cost, convenient control and operation, with a higher value.
Pilot Scale Study on Advanced Treatment of Coking Wastewater with Biological Activated Carbon Technology
Authors: Li Jin , Wang Guang Hua , Li Wen Bing , Zhu Zheng , Zhu Yin An
Published: December 2014

This paper reports about a pilot-scale feasibility study of Advanced Treatment of Coking Wastewater with Biological Activated Carbon technology based on the better experimental data of laboratory scale test .The self-designed of the Biological Activated Carbon Aerated tower was based on the optimal operating conditions of the results obtained from laboratory scale test.The removal efficiency to pollutants of efficient compound bacterium is estimated in biological activated carbon process through the variation of COD concentration, chromaticity, and Contrast the total ion chromatogram and UV absorbance spectrum of effluent and inflow.The results of the pilot-scale test show that BAC technology may be a suitable option for the advanced treatment of Coking Wastewater. the efficient degrading strains can reproduce on the activated carbon quickly.Concentrations of COD and chromaticity in outflow water were at a lower level (with COD about 60mg/L and chromaticity about 50 degree), the average COD removal rate greater than 50% and chromaticity removal rate greater than 70%.
Evaluating the Pozzolanic Activity of Spent Catalyst Partially Substituting Type II Portland Cement
Authors: Cunha A.L.C. , Gonçalves J.P. , Dweck J.
Published: December 2014

The catalyst discarded from fluidized catalytic cracking (FCC) units of heavy oil fractions presents in its composition typically high concentrations of silica and alumina, which give to it the possibility to be used as a pozzolanic material. The pozzolanic activity of a spent FCC catalyst from a Brazilian refinery oil was evaluated by studying the influence of the substitution in different degrees of a type II cement, by this catalytic residue on the hydration process and on the compressive strength of the formed materials. The influence of different particle size fractions of the residue and of its milling process was studied as well. The pozzolanic activity was evaluated by thermogravimetry (TG), derivative thermogravimetry (DTG) and non-conventional differential-thermal analysis (NCDTA). The results show that the chemical pozzolanic activity is enhanced when the sample presents a higher specific surface, as well as, the milling of the residue it is fundamental in order to be accepted and used as a pozzolanic material on partial substitution to cement.
Influence of the Crushing Process of Recycled Aggregates on Concrete Properties
Authors: Pedro Diogo , de Brito Jorge , Evangelista Luís
Published: December 2014

This work intends to evaluate the (mechanical and durability) performance of concrete made with coarse recycled concrete aggregates (CRCA) obtained using two crushing processes: primary crushing (PC) and primary plus secondary crushing (PSC). This analysis intends to select the most efficient production process of recycled aggregates (RA). The RA used here resulted from precast products (P), with strength classes of 20 MPa, 45 MPa and 65 MPa, and from laboratory-made concrete (L) with the same compressive strengths. The evaluation of concrete was made with the following tests: compressive strength; splitting tensile strength; modulus of elasticity; carbonation resistance; chloride penetration resistance; capillary water absorption; and water absorption by immersion. These findings contribute to a solid and innovative basis that allows the precasting industry to use without restrictions the waste it generates.
Mortars with Phase Change Materials - Part I: Physical and Mechanical Characterization
Authors: Cunha Sandra , Aguiar José , Ferreira Victor , Tadeu António , Garbacz Andrzej
Published: December 2014

In a society with a high growth rate and increased standards of comfort arises the need to minimize the currently high energy consumption by taking advantage of renewable energy sources. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. However, the incorporation of phase change materials in mortars modifies its characteristics. The main purpose of this study was the production and characterization in the fresh and hardened state of mortars with incorporation of different contents of PCM in mortars based in different binders. The binders studied were aerial lime, hydraulic lime, gypsum and cement. For each type of binder, different mortars were developed with different content of PCM. The proportion of PCM studied was 0%, 20%, 40% and 60% of the mass of the sand. It was possible to observe that the incorporation of PCM in mortars caused differences in properties such as workability, microstructure, compressive strength, flexural strength and adhesion.
Evaluation of the Mechanical and Environmental Behavior of Alkali-Activated Mortars Containing PU/EVA-Based Waste
Authors: Trein Fabiano André , Vargas Alexandre Silva , Rodrigues Marco Antônio Siqueira , Gomes João Paulo Castro
Published: December 2014

The objective of this study is to evaluate the use of polyurethane (PU) coated textile wastes processed with ethylene-vinyl acetate (EVA) as lightweight aggregates in fly ash-based and alkali-activated metakaolin mortars, targeting the development of non-structural elements for civil construction. The PU/EVA waste was processed in three different proportions: 30/70, 50/50 and 70/30. Reference mortars were prepared using a 1:2 (fly ash + metakaolin: conventional construction sand) ratio, by mass. The PU/EVA-waste-containing mortars were prepared via partial replacement of natural sand with the waste in percentages of 10%, 20%, 30% and 40%, relative to the volume of the sand. The activators used in all mortars were NaOH and Na2SiO3. The mortars were cured at 80 °C for 21 hours and subsequently removed from the molds and maintained at room temperature until testing was conducted for compressive strength (at ages of 7, 28 and 91 days), leaching (7 days) and solubilization (7 days). Based on the results for compressive strength, the optimum PU/EVA content was 50% for a sand-to-waste replacement percentage of 40%. At an age of 28 days these mortars reached strengths greater than 2.5 MPa which, from a mechanical standpoint, allows for the production of non-structural elements for civil construction like sealing blocks, side walls or finish mortars. From an environmental perspective, no hazardous substances were detected in the leaching and solubilized extracts in any of the PU/EVA waste containing mortars.
Study of Timber and Concrete with Rubber Waste Composite Beams Applied to Bridges
Authors: Pinheiro Luís Henrique Bueno , Matthiesen José Antônio , Akasaki Jorge Luís
Published: December 2014

In order to overcome the hydrographic network, the landforms, and the most different types of barriers, many timber bridges were constructed around the world, especially in secondary roads where the raw materials (wood) can be found in the vicinity, what reduces the construction costs.The deck can be made of reinforced concrete with the purpose of increasing the durability, strength and stiffness of these structures, and using rubber particles can not only decrease the costs and impact on the environment, but can also confer some advantages on the structure, such as a better impact absorption, and a lower cracking due to the abrasion wear, water absorption or self-weight.The analysis of the bending behavior of these superstructures was performed through the study of ten mixed T section composite beams, with wooden web (mimicking the stringers) and a reinforced concrete top flange (mimicking the deck) with varying rubber waste percentage. Steel bars set to “X”, glued with epoxy resin on the wood, allowed the connection between wood and concrete, reducing manufacturing costs with high shear strength resistance. The constituent materials were characterized mechanically and the composite beams were equipped with a dial indicator and strain gauges, and then broken in flexure tests. At the same time, the rubber particles percentage was correlated with the following parameters: stress, strain, elasticity modulus, loads and displacements, what enabled us to find which rubber addition percentage was most adequate in order for this kind of structure to be in accordance with the project requirements for the resistance.
Evaluation of the Influence of PU/EVA Waste-Based Lightweight Aggregates on the Physical Properties of Alkali-Activated Mortars
Authors: Trein Fabiano André , Vargas Alexandre Silva , Rodrigues Marco Antônio Siqueira , Gomes João Paulo Castro
Published: December 2014

The objective of this study is to evaluate the effect of the relationship of waste polyurethane (PU) and Ethylene-Vinyl Acetate (EVA), as a replacement for conventional construction sand, on the physical properties of water absorption, bulk density and open porosity of fly ash-based and alkali-activated metakaolin mortars. By means of processing involving extrusion and milling, PU/EVA-based aggregates were prepared in three proportions: 30/70, 50/50 and 70/30. The reference alkali-activated mortars were prepared using a 1:2 (fly ash + metakaolin : conventional construction sand) ratio, by weight. The waste-containing mortars were prepared via partial replacement of construction sand with the PU/EVA waste in percentages of 10%, 20%, 30% and 40%, relative to the volume of sand. The activators used in all mortars were NaOH and Na2SiO3. The mortars were cured at 80°C for 21 hours. Based on the procedures of ASTM C 642, the water absorption, open porosity and bulk density of the alkali-activated mortars were determined at the ages of 7, 28 and 91 days. The open porosity and water absorption values ​​increased as the amount of sand replaced with PU/EVA waste increased. The absorption values ​​were found to be in the range from 8.0% to 17.00%. The values ​​obtained for open porosity varied from 20.00% to 29.00%. With regard to bulk density, the behavior was reversed: increasing the amount of sand replaced by waste, decreased the bulk density value. The values ​​ranged between 2.10 and 2.48 kg/dm3. Therefore, based on these results, mortars containing up to 40% PU/EVA have potential for use in the manufacture of non-load-bearing elements for civil construction.
Mortars with Phase Change Materials - Part II: Durability Evaluation
Authors: Cunha Sandra , Aguiar José Barroso , Ferreira Victor , Tadeu António , Garbacz Andrzej
Published: December 2014

The industry of construction is responsible for the high consumption of raw materials, energy and waste production. As such, it becomes imperative to develop and study new constructive solutions with greater sustainable value. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reducing the use of heating and cooling equipment, using only the energy supplied by the sun. However, the incorporation of phase change materials in mortars modifies its characteristics. The main focus of this study was the durability of mortars with PCM incorporation based in different binders. The binders studied were aerial lime, hydraulic lime, gypsum and cement. For each type of binder, different mortars were developed with different content of PCM. The proportion of PCM studied was 0% and 40% of the mass of the sand. It was possible to observe that the incorporation of PCM in mortars caused differences in properties such as water absorption by capillarity, water absorption by immersion and degradation after freeze-thaw cycles.
Mechanical Properties of Adobe Made with Sugar Cane Bagasse and “Synthetic Termite Saliva” Incorporation
Authors: Corrêa Andréa Aparecida Ribeiro , de Paula Protásio Thiago , de Lima José Tarcísio , Tonoli Gustavo Denzin , Mendes Lourival Marin
Published: December 2014

Among non-conventional materials available in Brazil for construction, sugar cane bagasse lignocellulosic particles and “synthetic termite saliva” are included. The utilization of such particles as reinforcement and the “synthetic termite saliva” for soil chemical stabilization in adobe production were not investigated in the literature yet. Therefore, this research aimed to evaluate the mechanical properties of adobes produced with those materials. The soil used was Red Latosol Cambisol type with clayey texture with kaolinite presence, and particle size correction for 50% sand. Bagasse sliver particles were washed with residual water of the distillation process at 45°C and air dried. Their density and chemical composition were determined. The adobes were produced with 30x15x8cm-size wood molds. The following samples were analyzed: adobes without particles (control); and adobes with bagasse incorporation at 2%, 4% and 6% based on dry mass and “synthetic termite saliva” at 1:1500 and 1:500 proportions. Aluminum sulfate solvent was applied at 1:5,000. The adobes were stored in a covered warehouse until complete drying. Compression and static bending strength were evaluated. The results showed a positive interaction between adobe components and compression strength, which was improved up to 60%. The best composition tested was 6% sugar cane bagasse and “synthetic termite saliva” at 1:500.
Buckling of Bamboo Masts with Interposed Spacers
Authors: Silva Fernando José , Lana Bernardo Félix Santiago , Rodrigues Francisco Carlos , Moreira Luís Eustáquio
Published: December 2014

A hollow bamboo in its raw state, from the geometrical point of view and language engineering can be defined as an element of tubular bar, not prismatic, approximately circular cross sections, stiff by intermittent internal disks positioned along the bar. The decrease in the diameter and wall thickness usually happens from the bottom up, the basal part may contain some exceptions, with sections of the base with diameters smaller than the second, then to diminish steadily to the top. This architecture has a genetic component that resulted from constant interactions of bamboo with the actions of wind, which stimulated increased local resistance of the most requested points mechanically, not only by concentrated lignification in cellulosic tissues, such as the geometric localized variations. From the viewpoint of composite materials science, bamboo can be defined as a composition of two different materials, a first fiber and vessels oriented and aligned along the internodal stem sections, which connect to another material with fibers and vessels tangled - anastonose - intermittent stiffeners composing the above cited nodes. In both materials vessels and fibers are surrounded by a parenchymathous matrix of hollow cells that store sugars. The mechanical point of view, bamboo, due to the configuration, the rigidity and strength components and a tubular geometry is a flexible structural element with high mechanical resistance. This flexibility makes the long elements have low load capacity in flexion compression, if the goal is the application of bamboo in construction structures. This issue can be circumvented by systemic compositions, called masts, [1,2] which can be applied in a single long bamboo element resistant to relatively high compressive loads. In the present investigation, four parallel bamboos 5.5 meters long, the speciesPhyllostachys pubescensare discontinuously connected by bamboo segments interposed fixed by steel pins, achieving this composition with a load limit of 48 kN in controlled experiments. These experiments were also used and motivated to find the numerical modeling by the MEF, whose results were widely discussed.
Natural Aging in Heat-Treated Medium-Density Fiberboard Panels
Authors: Oliveira Stefânia Lima , Mendes Rafael Farinassi , Freire Ticyane Pereira , Mendes Lourival Marin
Published: December 2014

Heat treatment of wood is a promising alternative in improving its dimensional stability. The action of heat ensures the good quality of the treated wood product, with better performance in environments with high humidity. To prove the positive effect of this treatment, a test in which the specimens are weathered for a certain period of time termed as natural aging was performed. The aim of this study was to evaluate the effect of aging on heat-treated medium-density fiberboard (MDF) panels. Commercial MDF panels produced with pinewood adhesive and urea-formaldehyde were used. The experiment included seven test treatments [at 200, 225, and 250°C heat temperatures for 5 and 10 min] and a control treatment (without heat treatment). The products subjected to these treatments were weathered for 40 days, and climatological data were monitored daily. The results suggested that: 1) There is a decreasing trend in density with increasing time and temperature; 2) the treatment time and temperature had no effect on the ownership of the static bending for modulus of elasticity (MOE); 3) the time period is correlated with the treatment temperature for modulus of rupture (MOR) property; and 4) the thermal treatment of MDF panels did not allow the maintenance of the properties of MOR and MOE static bending strength after natural aging.
Influence of Test Specimens Shape on Measurements of Electrical Resistivity of Concrete
Authors: Medeiros Ronaldo Alves , Lima Maryangela Geimba
Published: December 2014

The need to insert the durability factor on dimensioning concrete structures has been stimulating the development of new models to predict the service life of those structures. Among those new models, the use of data from Non-Destructive Testing (NDT) is recommended. It is known that electrical resistivity is a parameter related with permeability and, in consequence, with the resistance of the concrete against the intrusion of aggressive agents. Electrical resistivity may be monitored with time by a NDT method, by a low cost and easy execution technique. However, some parameters of this essay need to be further discussed in the literature aiming to standardize this technique. Thus, this study had the goal to verify the influence of test specimen’s shape in measurements of electrical resistivity. In order to that, cylindrical and prismatic test specimens have been molded from a same type of concrete and electrical resistivity was monitored during a period of 120 days. Results show significant differences between the values obtained. Test specimens in cylindrical shape had the higher results. A good correlation between factors was found with R2 higher than 0.94.
Use of PET Fibers in Reinforced Concrete Slabs Subjected to Flexure
Authors: Muñoz Rosana , Quintella Rogério Hermida , de Oliveira Carvalho Lisa Sahadia , da Silva Leite Bárbara Ariela , Velame Roberto Brito
Published: December 2014

The addition of fibers in order to obtain better performance of mechanical characteristics of concrete has been common place in the last fifteen years in Brazil. Following a request from the Faculty of Architecture at the Federal University of Bahia to replace the Eternit Wall panels with structural deterioration used in its mezzanine floor, this research was developed to analyze the flexural behavior of reinforced concrete slabs with the addition of PET (polyethylene terephthalate) fibers obtained from soda bottles. Selection of this material was based on sustainability since PET wastes represent a serious environmental issue although it can be recycled at a low cost. The importance of this work is based on verifying some of the characteristics of PET fibers reinforced concrete aiming sustainability of civil construction. After laboratory analysis of materials used for slabs, specimens and concrete slabs were shaped with and without PET fibers, being respectively submitted to standard axial compression and flexural tests. Despite the averages of compressive and flexural strengths of slabs with fiber being similar to those without fiber, the firsts presented a better result in terms of cracking, deformation and a less abrupt rupture.
Influence of Dimension Stones on the Increase of Radon Gas Levels Indoors
Authors: Amaral P.G.Q. , Artur A.C. , Bonotto D.M. , Galembeck T.M.B.
Published: December 2014

The present work features results on the possible increase of radioactive 222Rn gas in environments of human habitation, caused by the use of dimension stones inside constructions with poor air circulation. For the study, “granitic” stones were selected from Espírito Santo and Minas Gerais states, commonly used as decorative stones and as wall covering. They were subjected to petrographic analysis, determination of physical indexes and level of U, and were monitored to quantify the amount of 222Rn gas released. The rates of 238U in the rocks stood between 2.9 ppm and 37 ppm, and the amount of 222Rn gas released ranged between extremely low for six of the stones (up to 98 Bq/m3) and moderate to considerably high (between 471 and 2483 Bq/m3) for four others. From the calculations to cumulatively evaluate the radiation levels generated by radon release, nine samples are below the limit of 4 pCi/L set by the EPA– Environmental Protection Agency (U.S.A.) and one is above that limit, demonstrating the role of these stones in increasing radon levels in ill-ventilated environments.
Thermal Performance Characterization of a Modular System for Facade
Authors: Cardoso C. , Jalali S.
Published: December 2014

The developed system corresponds to multifunctional prefabricated modular elements that combine an insulation layer with a cast coating material for exterior that can imitate stone or concrete. These systems need auxiliary elements of fixing to connect them mechanically to the structural wall of the building, in order to ensure its stability, using anchorage, profiles, rails, among others. The use of these systems connected to the coating interrupts the continuity of thermal insulation, causing additional heat losses through linear and point thermal bridges, having an detrimental effect on thermal performance of the system. The development of fixing of present multifunctional panels was based on the evaluation and adoption of appropriate solutions in order to minimize thermal bridges and reinforce the stability of the panel. For evaluation purposes some models are evaluated, with different connecting systems, configurations and different materials such as aluminium, stainless steel, galvanized steel and Glass Fibre Reinforced Polymer (GFRP) profiles. The quantification of thermal bridges, for evaluation of thermal performance, has been made using computing programs, HEAT2 and HEAT3. The evaluation of a system developed in this research work, i.e. incorporating profiles in thermal insulation, shows a good thermal resistance contributing significantly to the thermal insulation and energy conservation in building.
Waste Management in the Reform and Adequacy of the Maracanã Stadium for the FIFA Football World Cup 2014
Authors: Vinciguerra Mariangela , Figueiredo Enio Pazini , Drummond Felipe , Zaeyen Carlos , Moreno Ícaro , Malafaia Bernard
Published: December 2014

This work aims to contribute to the minimization of solid construction waste at construction sites through the application of sustainability concepts in the construction industry, addressing the recommendations of the LEED certification. The object of study was the works of reform and adaptation of the Maracanã Stadium, venue of the final match of the 2014 FIFA World Cup. The methodology consists of visits to the construction site of the stadium, interviews with responsible people for the jobs and data analysis collected by the Maracanã Consortium Rio 2014 Report. Based on the data collected, it was evaluated the used strategies and tools in the construction to minimize the generation of waste. It was found that the strategies were well executed, contributing to the reduction of waste at the construction site and to the sustainable disposal of the generated waste. The strategies involved environmental, social and economic aspects, giving the construction an international certification for sustainable building.
High Temperature Oxidation of 9-12% Cr Materials P91 and P92 in Supercritical Water
Authors: Skoumalová Zuzana , Burda Jaroslav , Křečanová Eliška
Published: December 2014

The article summarizes the results obtained within a project PRAMEK. The project is focused on corrosion behavior of structural materials in water environment with supercritical parameters. Ferritic - martensitic materials P91 and P92 was evaluated. Multi-layered oxide was created on materials sample surface after 1000 hours long exposures in Supercritical Water Loop (SCWL) and Supercritical Water Autoclave (SCWAc) under SCWR operational parameters (600 °C, 25 MPa). The outer layer consisted of magnetite was porous and may tend to exfoliate. The inner layer is formed by spinel with Cr and Fe oxides. Microstructure of materials P91 and P92 and surface oxidic scales were evaluated by means of light and scanning electron microscopy equipped with wave and energy spectroscopy.
Cleanness and Mechanical Properties of Steel after Remelting under Different Slags by ESR
Authors: Pribulová Alena , Futáš Peter , Bartošová Marianna
Published: December 2014

Quality of machine production is very close-knit with quality of metallurgical semi-products and with improvement their working properties. It can be achieved first of all by decrease of sulphur and non-metallic inclusions content in metal. Improvement of working properties provide remelted processes above an electro slag remelting (ESR). The slags play very important role by ESR process. By experiments steel with next chemical composition was used: C (0,9 – 1,1%), Mn (0,30 – 0,50%), Si (0,15 – 0,35%), Cr (1,30 – 1,65%), Ni (max.0,30%), Cu (max.0,25%), P (max.0,027%), S (max.0,030%). The steel was remelted under 8 types of slags on the base of CaO, Al2O3, CaF2 and SiO2 in different ratios. The contribution deals with influence of chemical composition of slag on mechanical properties and cleannes of metal after electro slag remelting. Variation of slag chemical composition enables to change chemical composition of remelted steel, to reduce the non-metallic inclusions and sulphur content and to improve the mechanical properties of steel.
IF Steel Effect of Rate Deformation on the Fracture Surface Change
Authors: Mihaliková Mária , Német Miroslav , Vojtko Marek
Published: December 2014

Strain rate is a significant external factor and its influence on material behaviour in forming process is a function of its internal structure. In this contribution the influence of loading on the deformation IF steel is investigated using rotate hammer. To study the influence of rate deformation from 8.33 x 10-3 s-1 to 4000 s -1 to changes in the fracture of steel sheet used for bodywork components in cars. Experiments were performed on samples taken from interstitial free (IF) grade strips produced by cold rolling and hot dip galvanizing. Material strength properties were compared based on measured values, and changes to fracture surface character were observed.
Use of Geopolymer Matrix Composites in the Construction of Fire Doors
Authors: Dufkova Iva , Bilketay Sezer , Kroisová Dora , Kovačič Vladimír
Published: December 2014

Protection and safety of workers in plants with the danger of fire is always the first place. They are currently used in devices that are designed to quickly separate the fire residues from workers such as steel fire doors filled with non-combustible materials that insulate the prescribed time up to 600 ° C. As the demands for safety was the requirement for resistance to temperatures higher than 600 ° C. [1, 2]. Post relates to improvements refractory properties of steel gates based geopolymer matrix composites. They are analyzed the properties of different materials such as fillers geopolymer matrix, durability and affinity to steel parts of the door structure.