Lessons learned from the development and manufacture of ceramic reusable surface insulation materials for the space shuttle orbiters

Three ceramic, reusable surface insulation materials and two borosilicate glass coatings were used in the fabrication of tiles for the Space Shuttle orbiters. Approximately 77,000 tiles were made from these materials for the first three orbiters, Columbia, Challenger, and Discovery. Lessons learned in the development, scale up to production and manufacturing phases of these materials will benefit future production of ceramic reusable surface insulation materials. Processing of raw materials into tile blanks and coating slurries; programming and machining of tiles using numerical controlled milling machines; preparing and spraying tiles with the two coatings; and controlling material shrinkage during the high temperature (2100-2275 F) coating glazing cycles are among the topics discussed

An Evaluation of Community-Based Weaving Program Implementation in Gamplong Tourist Village Sleman Yogyakarta

The objectives of this study were to evaluate the implementation of community-based weavingprograminGamplongtouristvillageandtofindtheobstaclesinexecutingthe program for the local community. This study applied descriptive qualitative research method. Data were collected through observation, interviewing, and document analysis. The data analysis techniques employed in this study were data reduction, data display, and conclusion drawing. The result of this study showed: First, planning phase consisted of preparing the regeneration of weavers and local raw material plantation. Second, implementation phase comprised the execution of predetermined plan of weaving training as a regeneration effort and making use of local raw material. Third, evaluation phase was done to evaluate the regeneration effort of weavers and fulfillment of local raw materials. Fourth, the problems faced by the administrator of the weaving program in Gamplong Tourist Village were about natural resources, particularly raw material for weaving and human resources relating to the regeneration of weavers.     Keywords: Evaluation, Weaving, Tourist Village, Community-Base

Coal gasification systems engineering and analysis. Appendix A: Coal gasification catalog

The scope of work in preparing the Coal Gasification Data Catalog included the following subtasks: (1) candidate system subsystem definition, (2) raw materials analysis, (3) market analysis for by-products, (4) alternate products analysis, (5) preliminary integrated facility requirements. Definition of candidate systems/subsystems includes the identity of and alternates for each process unit, raw material requirements, and the cost and design drivers for each process design

Highly effective adsorption of synthetic phenol effluent by a novel activated carbon prepared from fruit wastes of the Ceiba speciosa forest species

Fruit wastes of the Ceiba speciosa forest species were employed as raw material for preparing activated carbon towards removing phenol from water. Concave cavities spread over the entire material surface were observed from characterization results, resulting in a high surface area, 842 m2 g−1. Adsorption isotherm and kinetic studies were performed under the best conditions of pH (7) and adsorbent dosage (0.83 g L−1). An increase in temperature from 298 K to 328 K disfavored the phenol adsorption, decreasing from 156.7 to 145 mg g−1 for the best-fit model, Langmuir. The thermodynamic results indicated that the phenol adsorption was spontaneous, favorable, and exothermic. The phenol concentration decay shows that the equilibrium is reached at 120 min. The pore volume and surface diffusion model (PVSDM) was employed satisfactorily to describe the phenol decay behavior. The surface diffusion coefficient values were in the range of 10−9 cm2 s−1. The external and the internal mass transfer were the rate-controlling mechanisms. Therefore, the application of fruit wastes from Ceiba speciosa as raw material for preparing activated carbon proved very efficient towards removing phenol from an aqueous medium. The activated carbon is an alternative material to suppress water contamination due to phenol-derived species

Pengaruh Biaya Bahan Baku Dan Biaya Tenaga Kerja Terhadap Volume Produksi Pada Usaha Loyang Pak May Padang

This study aims to determine the effect of raw material costs and labor costs on production volume in Pak May Padang's baking pan business. Taking this title is based on the phenomenon that many business actors do not understand the calculation of a production cost. This study uses a type of quantitative research. The data taken is in the form of secondary data by conducting direct interviews with business owners, by preparing materials for questions and viewing notes on purchases of raw materials during the 2017-2021 period. This study conducted a classic assumption test, hypothesis testing using SPSS version 21. With the results of the study stating that seeing the results of the tests that have been carried out proves that partially the raw material costs and labor costs have a significant effect on production volume, and simultaneously both variables have an influence which is sig to production volume, and it can also be seen that Adjusted R Square is 0.651 or 65.1% This means that 65.1% of the variable production volume is influenced by raw material costs and the remaining labor costs are 34.9% influenced by variables other than the variables of this stud

Rancang Bangun Alat Uncoiler Cutting Plat Strip

Outdoor Furniture Company is a company engaged in the manufacturing industry that produces goods according to orders received. In the production process, one of the orders currently being produced is found a condition that makes the production process not effective, namely the process of preparing raw materials which is still done manually. Therefore, this research was carried out by making a design for an uncoiler as well as being useful as a cutter for the process of preparing raw materials. The method used in this research is the Ulrich method, where this method consists of the stages of the development process to get the best design as needed. Based on the results of design, manufacture, and testing, an uncoiler cutting plate strip is produced as a tool for one of the manufacturing processes for cutting strip plate material. This tool is designed using Fusion 360 software and the Ulrich method for selecting the best concept from 3 existing concepts. After testing, this tool is able to cut strip plate material with various dimensions according to the plan and has a precision level under 5 mm, and is able to cut at a speed of less than 38 seconds, which means this tool is better than existing products in the company

Removal of m-xylene from water by impregnated activated carbon

Volatile organic compounds (VOCs) are the main matters which can pollute water therefore, must be controlled under increasingly stringent environmental regulations.This work analyses the adsorption of impregnated active carbons prepared with oak bark to remove m-xylene from aqueous solutions. When the impregnation step is performed on the raw material then carbonizations of activated carbon was carried out. Not expensive raw material and chemical agent were used as active species where used for preparing the appropriate adsorbent for removal of m-xylene from water. In this work the effect of adsorption temperature, pH and the initial concentration of process were investigated. It is clear that with increasing the initial concentration the removal efficiency of adsorption will be increased. The effect of temperature was studied by increasing the temperature from 20 to 60 °C. with increasing the temperature the removal efficiency will be increased in the range of 20-60 °C

Solid Freeform Fabrication of Functional Silicon Nitride Ceramics by Laminated Object Manufacturing 1

The processing of silicon nitride (Si3N4) structural ceramics by Laminated Object Manufacturing (LOM) using ceramic tape preforms was investigated. The key processing stages involved green shape formation (which used the LOM process), followed by the burnout of all organics, and final densification by pressureless sintering. Two material systems were considered. These were a) monolithic Si3N4 and b) a preceramic polymer infiltrated Si3N4. The raw materials for the process were tape preforms of Si3N4, which were fabricated by standard tape casting techniques. Mechanical property data obtained for the LOM processed Si3N4 showed high strength and fracture toughness values. The room temperature and high temperature (1260 o C) flexural strengths were in the range of 700-900 MPa and 360-400 MPa, respectively. The fracture toughness averaged from 5.5-7.5 MPa.m1/2. These strength and fracture toughness values are comparable to those reported for conventionally prepared Si3N4 ceramics. Thus, this research demonstrated that the LOM technique is a viable method for preparing functional Si3N4 ceramics with good physical and mechanical properties.Mechanical Engineerin

Establishing The Equipment-methodical Support For Determining The Properties Of Extracts Of Grape Pomace Extracts Produced In The Subcreative Water Environment

Research objective: development of a high-pressure reactor for researching the process of extraction of grape pomace by the subcritical water and determining the parameters, providing the maximum yield of various target products – biologically active substances; formation of methodological support for raw material preparation, qualitative and quantitative analysis of extracts, produced by the subcritical extraction. As a result of simulation in the ANSYS system of the stress-strain state of the walls of the reactor chamber and a set of calculation operations, a high-pressure reactor was created that meets the requirements. The formed methodical complex for determining the physicochemical properties of extracts and the content of various biologically active substances included methods for preparing samples and determining the yield of dry extractive substances, evaluation of extraction of polyphenols (tannic-catechol complex), evaluation of extraction of reducing substances, identification furfural and gallic acids, estimation of free organic acids in terms of tartaric acid, evaluation of antioxidant activity of extracts). This methodological complex allows us to estimate the physico-chemical properties of the extracted biologically active substances

Microencapsulation of ellagic acid from pomegranate husk and karaya gum by spray drying

Objective: The aim of this study was to obtain and characterize microcapsules with Ellagic Acid (EA) from pomegranate as core material and Karaya Gum (KG) as wall material. Methods: EA was obtained from dry pomegranate peel powder via methanolysis and quantified by HPLC. Microcapsules were obtained preparing a dispersion containing KG and EA in phosphate buffer pH 8. The dispersion was processed in a spray dryer under specific conditions (inlet temperature at 150 °C, feed flow at 30% and aspirator at 100 %) for obtaining of microcapsules. Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were used for characterization. Results: Obtained material contains 98.03±2.82 mg EA/g of pomegranate peel. FTIR showed that there were changes in the molecular structure of microcapsules referred to raw materials. SEM confirmed that particles obtained had micron-size (1-5 µm). DSC analysis showed that raw materials had glass transition temperatures of 79.58 and 83.41 °C and for microcapsules the value was67.25 °C. Conclusion: Methanolysis is a viable technique for the obtaining of EA from the peel of pomegranate. KG shows good potential for be used as wall material for EA microencapsulation