Worldwide, enormous amounts of waste cause major environmental issues, including scrap tires and plastic, and large waste, a consequence of the demolition of buildings, including crushed concrete, crushed clay bricks, and crushed thermo-stone. From that point, it’s possible to consider that the recycling processes for these materials and using them in the manufacturing field will reduce the adverse effects on the environment of these wastes and the consumption of natural resources. Sustainable concrete blocks can be considered as one of the products produced by using these materials as partial volume replacement of the coarse, fine aggregate, or cement content, considering their dry density, workability, absorption, compressive strength, and thermal conductivity tests evaluate their performance- and conformity with specifications. The results of tests on samples of sustainable concrete blocks showed the feasibility of using demolished building waste as aggregates instead of natural materials for their production.
This study investigated the structural behavior of a beam–slab member fabricated using a steel C-Purlins beam carrying a profile steel sheet slab covered by a dry board sheet filled with recycled aggregate concrete, called a CBPDS member. This concept was developed to reduce the cost and self-weight of the composite beam–slab system; it replaces the hot-rolled steel I-beam with a steel C-Purlins section, which is easier to fabricate and weighs less. For this purpose, six full-scale CBPDS specimens were tested under four-point static bending. This study investigated the effect of using double C-Purlins beams face-to-face as connected or separated sections and the effect of using concrete material that contains different recycled
... Show MoreMost reinforced concrete (RC) structures are constructed with square/rectangular columns. The cross-section size of these types of columns is much larger than the thickness of their partitions. Therefore, parts of these columns are protruded out of the partitions. The emergence of columns edges out of the walls has some disadvantages. This limitation is difficult to be overcome with square or rectangular columns. To solve this problem, new types of RC columns called specially shaped reinforced concrete (SSRC) columns have been used as hidden columns. Besides, the use of SSRC columns provides many structural and architectural advantages as compared with rectangular columns. Therefore, this study was conducted to explain the structura
... Show MoreThe sorption of Cu2+ ions from synthetic wastewater using crushed concrete demolition waste (CCDW) which collected from a demolition site was investigated in a batch sorption system. Factors influencing on sorption process such as shaking time (0-300min), the initial concentration of contaminant (100-750mg/L), shaking speed (0-250 rpm), and adsorbent dosage (0.05-3 g/ml) have been studied. Batch experiments confirmed that the best values of these parameters were (180 min, 100 mg/l, 250 rpm, 0.7 g CCDW/100 ml) respectively where the achieved removal efficiency is equal to 100%. Sorption data were described using four isotherm models (Langmuir, Freundlich, Redlich-Peterson, and Radke-Prausnitz). Results proved that the pure ads
... Show MoreIn despite of the expansion of using the dummy variables as a explanatory variables, but their using as a dependent variables is still limited, and the reason of that may be return to may problems when using dummy variables as a dependent variables. the study aimed to using the quality Response Models to Measuring Efficiency of cows farms by random sample including (19) farm from (Abi gherak district). The study estimating the transcendental logarithmic production function by using stochastic frontier Analysis (SFA) to interpret the relation between the return achieved from the cows farms as a dependent variables and each of labor and capital as an independent variables. the function indicates that increasing in labor by (100%) will
... Show MoreThis study was aimed to measure marketing efficiency and study important factors affecting , using TOBIT qualitative response model for wheat crop in Salahalddin province. Results revealed that independent factors such as (marketing type, crops duration in the field, average marketing cost, distance between farm and marketing center, and average productivity) had an impact on wheat marketing efficiency. This impact varied in size and direction due to value of parameters. Values of marketing efficiency fluctuated within cities and towns in the province. The average value on the province level was 76.75%. This study was recommended developing marketing infrastructures which is essential to efficiency increases. In addition, it is impo
... Show MoreIn the present work theoretical relations are derived for the efficiency evaluation for the generation of the third and the fourth harmonics u$ing crystal cascading configuration. These relations can be applied to a wide class of nonlinear optical materials. Calculations are made for beta barium borate (BBO) crystal with ruby laser /.=694.3 nm . The case study involves producing the third harmonics at X. =231.4 nm of the fundamental beam. The formula of efficiency involves many parameters, which can be changed to enhance the efficiency. The results showed that the behavior of the efficiency is not linear with the crystal length. It is found that the efficiency increases when the input power increases. 'I'he walk-off length is calculated for
... Show MoreChemical pesticides have an impact on other living organisms in addition to their intended target organisms. Any chemical pesticide is therefore made safe for use by examining its biological characteristics and side effects. The present study was aimed at determining the resistance efficiency of six bacterial isolates obtained from malathion-contaminated soils. Bacteria were isolated from soil samples collected in Adhamiya, Baghdad, Iraq. Biochemical tests and VITEK 2 compact equipment were used to identify the bacterial isolates. Primary and secondary screening tests were conducted on the bacterial isolates for resistance against malathion pesticides. The optimal bacterial growth conditions were determined in malathion-contaminated media.
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