effect of adding probiotic bacteria on bauxite waste mud

Bauxite waste sludge is quite dangerous when polluted into the surrounding environment. The number is increasing with the higher mining production. The utilization is still not maximized hence it is unbalanced to the increasing number, and it is necessary to use on a large scale. Sub-grade soil could use a lot of bauxite waste sludge but in reality, this waste is unsafe to use and its characteristics are mud the requirements of bearing capacity according to the AASHTO and USCS Classification unfulfilled. This study aims to determine the effect of the use of probiotic bacteria in bauxite waste on its physical characteristics and pH value. This experimental research method develops test objects according to ASTM standards with the same weight of bauxite waste and variations in the number of probiotic bacteria, namely 25 ml, 50 ml, 75 ml, and 100 ml and the incubation time of bacteria is 7 days, 14 days, 21 days, 28 days, 35 days, and 42 days. The results showed that the test specimens with more bacteria and longer incubation times resulted in lower pH values and physical characteristics that fulfilled the requirements for sub-grade soil.

ANALISIS PENGARUH PENAMBAHAN IJUK 0,25% DAN 0,5% PADA CAMPURAN BETON fc’ 14,5 MPa (NON STRUKTUR)

Concrete is the majority of materials used in construction in Indonesia in general. Concrete mix innovations are needed so that concrete has better quality and quality. Innovation in concrete mixture one of them by using organic waste. In addition to improving quality, organic waste used is expected to reduce global warming. In Nagari IV Koto Palembayan ijuk from enau trees is not processed and left alone, so over time the ijuk can become waste. In this study discussed the effect of the addition of ijuk in the concrete mixture against the strong press of concrete. The targeted concrete press strong value is 14.5 MPa. The test object is made by varying the amount of ijuk addition in the concrete mixture by 0.25% and 0.5%. The test object used is a cylinder measuring 15cm in diameter and 30 cm high. Testing was conducted when the concrete was 7 days old, 14 days and 28 days old using 2 samples of test objects. The results showed a strong value of normal concrete press age of 28 days obtained at 15.57, while the strong value of additional concrete press ijuk 0.25% and 0.5% obtained by 19.82 MPa and 18.26 MPa. The results showed additional concrete ijuk 0.25% increased by 27.30% from the normal concrete press strength and the strong value of additional concrete press ijuk 0.5% also increased by 17.28% from the strong normal concrete press.

Computing Gripping Points in 2D Parallel Surfaces Via Polygon Clipping

To generate suitable grasping positions between tessellated handling objects and specific planar grippers, we propose a 2D analytical approach which uses a polygon clipping algorithm to generate detailed information about the intersection between both objects. With the generated knowledge about the intersection we check whether its shape fits to the set criteria of the operator and represents a valid grasping position. Before the polygon clipping algorithm is applied, a preprocessing step is performed, where appropriate surfaces from the handling object and the gripper are extracted. After rotating all surfaces into a common plane, potential clipping positions are detected and the clipping is performed to get an accurate intersection detection. The validation shows comparable running times to a OBBTree algorithm (0.1 ms per grasping position) while increasing the stability of the results from 30 to 100% for the evaluated test objects.

Optimizing Flexural Strength of Concrete Fc’ 14,5 MPa Using Acetylene Welding Carbide Waste

Replacing the main material using unused materials such as hazardous waste can be utilized in concrete innovation. One of the hazardous wastes that can utilize the waste generated from the acetylene welding process. The waste has hardening properties when exposed to water. Its properties are almost the same as cement can replace or add part of the cement mixture. Conducted this research was to determine the effect of using carbide waste from the acetylene welding process on the flexural strength of concrete. The experimental method is carried out by making test objects in the laboratory. The proportions of waste added were 7%, 10%, and 12% by weight of cement. The test object used is in the form of a beam with dimensions of 60 cm x 15 cm x 15 cm. The planned initial quality is concrete F'c 14.5 MPa (K175). The flexural strength test was carried out at the age of 27 days of concrete. From the results of the research carried out, it is found that the use of carbide waste from the acetylene welding process has not been able to improve the quality of concrete significantly. The highest flexural strength was obtained from waste at 7%, with a flexural strength value of 9.692 Mpa. So from these results, it can be used as a reference in the utilization of carbide waste from the acetylene welding process.

Study on Soil Throwing Performance and Ditch Depth Stability of Ditching Device in Sandy Orchards in Southern Xinjiang

In order to solve the problems of serious soil reflux and poor stability of ditch depth in the existing ditching organic fertilizer fertilization device in grey desert and loess orchards, rotary tillage theory and software simulation were used to conduct kinematic analysis of soil particles and ditching blade in the ditching process, and meanwhile, modeling and simulation are carried out for sand soil particles by using EDEM software, so as to determine the action mechanism of soil, blade and fairing in ditching process of grey desert and loess. The abstract on this basis, the quadratic orthogonal regression-rotation combination experiment was designed. The soil bin test was carried out by taking the cutter wheel speed, ditching depth and inclination of curved surface as the influencing factors, and the throwing distance and the stability of ditch depth as the test indexes. And it was concluded that the order of the influence of the operating parameters of the ditching device on the soil throwing distance is ditching depth > inclination of curved surface > cutter speed, and the order of the influence on the stability of the ditch depth is ditching depth > cutter speed > Inclination of curved surface. Finally, the optimized operating parameters of the ditching device are as follows: the cutter wheel speed is 119.61 r·min−1, the inclination of curved surface is 30.07°, the ditching depth is 35.52 mm, the soil throwing distance is 57.31, and the stability of ditch depth is 87.43. With these parameters as test objects, 10 groups of single factor tests were carried out to obtain that the soil throwing distance is 58.33, and the stability of ditch depth is 86.51, which were basically consistent with the expected results of the optimization test, and also in line with the relevant agronomic standards.

Road Surface Characteristics for the Automotive 77 GHz Band

In order to achieve a safety proof of autonomous driving using simulations, information about the environment has to be determined, which is not sufficiently available until now. This work is concerned with road surfaces and their scattering of radar signals. As it is not enough to look at geometries, as it is already done for many ray tracing approaches, also material and composition have to be investigated. Therefore, measurements are performed using a SAR setup in a laboratory as well as open space measurements using a radar evaluation board on a testing area of the Federal Highway Research Institute. The SAR setup enables a quick estimation on differences in reflection of different test objects. With the result from the latter values for the relative permittivity are calculated for different road surface types exploiting Fresnel's equations. The differences in reflection depending on material and surface structure of the road see in the measurements of both setups are discussed in the paper.

THE EFFECT OF ADDING CEMENT WASTE ON THE QUALITY OF CONCRETE COMPRESSIVE

Infrastructure development is one of the important aspects of the progress of a country where most of the constituents of infrastructure are concrete. The most important constituent of concrete is cement because its function is to bind other concrete materials so that it can form a hard mass. The large number of developments using cement as a building material will leave quite a lot of cement bags.In this study, the authors conducted research on the effect of adding cement waste to the compressive strength of concrete. This study used an experimental method with a total of 24 test objects. The test object is in the form of a concrete cylinder with a diameter of 15 cm and a height of 30 cm and uses variations in the composition of the addition of cement waste cement as a substitute for fine aggregate, namely 0%, 2%, 4% and 6%. K200). The compressive strength test was carried out at the age of 7 days and 28 days.The test results show that the use of waste as a partial substitute for fine aggregate results in a decrease in the compressive strength of each mixture. at the age of 7 days the variation of 2% is 16.84 MPa, 4% is 11.32 MPa and for a mixture of 6% is 6.68 MPa. Meanwhile, the compressive strength test value of 28 days old concrete in each mixture decreased by ± 6 MPa. So the conclusion is cement cement waste cannot be used as a substitute for fine aggregate in fc 16.6 (K200) quality concrete because the value is lower than the specified minimum of 16.6 MPa.

Effect of shell disinfection with AQUALYTE (NEUTRAL ANOLYTE) on inactivation of Salmonella enteritidis and quality of edible eggs

The results of studies, conducted by a number of scientists, prove that chicken eggs can cause food poisoning, as well as poultry. To prevent foreign microfloraingress into egg products, scientists have developed a number of methods aimed at the pathogenic microflora inactivation on the surface of the table eggs shells; nevertheless, the search for new methods is an urgent task. The article describes the results of the studies on the effect of disinfecting the shells of table eggs using AQUALYTE NEUTRAL ANOLYTE (NA) on the eggs quality. NA disinfecting activity was studied using cambric test objects. For the purposes of studying NA disinfecting efficiency, an experimental contamination of the surface of the table eggs shells with a test culture of Salmonella enteritidis was made. It was established that disinfection of the table eggs shells with 100% (2 min exposure) and 50% (5 min exposure) NA solutions provides Salmonella inactivation on the shell, and it does not affect the veterinary and sanitary parameters of eggs.

An experimental test of the Mocikat-Herwig theory of local turbulent heat transfer measurements on cold objects

Experimental results are presented of a test of the theory of local turbulent heat transfer measurements proposed by Mocikat and Herwig in 2007. A miniaturized multi-layer heat transfer sensor was developed and employed in this study. The new heat transfer sensor was designed to work in air and liquids, and this capability enabled the simultaneous investigation of different Prandtl numbers. Two basic configurations, namely the flow past a blunt plate and the flow past an inclined square cylinder, were investigated in test sections of wind and water tunnels. Convective heat transfer coefficients were obtained through conventional testing (i.e., employing thoroughly heated test objects) and using the new miniaturized sensor approach (i.e., utilizing cold test objects without heating). The main prediction of the Mocikat-Herwig theory that a specific thermal adjustment coefficient of the employed actual miniaturized heat transfer sensor should exist in the fully turbulent flow regime was proven for developed two-dimensional flow. The observed effect of the Prandtl number on this coefficient was in good agreement with the prediction of the asymptotic expansion method. The square cylinder results indicated the inherent limits of the local turbulent heat transfer measurement approach, as suggested by Mocikat and Herwig.