Water Formation Reaction under Interfacial Confinement: Al0.25Si0.75O2 on O-Ru(0001)

Confined nanosized spaces at the interface between a metal and a seemingly inert material, such as a silicate, have recently been shown to influence the chemistry at the metal surface. In prior work, we observed that a bilayer (BL) silica on Ru(0001) can change the reaction pathway of the water formation reaction (WFR) near room temperature when compared to the bare metal. In this work, we looked at the effect of doping the silicate with Al, resulting in a stoichiometry of Al0.25Si0.75O2. We investigated the kinetics of WFR at elevated H2 pressures and various temperatures under interfacial confinement using ambient pressure X-ray photoelectron spectroscopy. The apparent activation energy was lower than that on bare Ru(0001) but higher than that on the BL-silica/Ru(0001). The apparent reaction order with respect to H2 was also determined. The increased residence time of water at the surface, resulting from the presence of the BL-aluminosilicate (and its subsequent electrostatic stabilization), favors the so-called disproportionation reaction pathway (*H2O + *O ↔ 2 *OH), but with a higher energy barrier than for pure BL-silica.

An In-vitro study to compare the effect of four moisture contaminants on the shear bond strength of composite resin

The success of an Endodontic treatment relies on the position and morphology of root canals. It is important for a clinician to be familiar with the canal morphology to negotiate and thereby filling the canals with an inert material. But, the possibility of negotiating the canals with the use of conventional technique alone is difficult. Hence, careful examination with the use of advanced techniques to enhance vision is required to minimize the rate of treatment failures. To compare the efficiency of three methods Cone-Beam computed Tomography (CBCT), clinical analysis, AND Dental Loupes in detecting the MB2 canal in maxillary first molars.One hundred and fifty extracted intact permanent molars were collected. Two examiners i.e., one Endodontist and a Radiologist examined CBCT images of teeth for the number and position of root canals. The first stage included unaided examination using an explorer and K- files. While those teeth that were failed to locate the canals were examined using dental loupes for better magnification. The results were analyzed by McNemar's tests with Bonferroni correction, and Chi-square test using SPSS software v21.Among 150 extracted teeth that were compared,MB2 was detected using CBCT in around 68% of the teeth, while with the use of naked eye and dental loupes, it was found to be around 30% and 66% respectively and the difference in the detection rates was statistically significant.With the view of the parameter under consideration, CBCT has high detection rates followed by dental loupes and naked eye vision. The efficiency of CBCT scans and dental loupes in detecting a second mesio-buccal canal, Thus making it more likely to be treated by the clinician.

Comparative evaluation of the efficiency of cone-beam computed tomography, clinical analysis, and dental loupes in detecting the MB2 canal in maxillary first molars. An in-vitro study

The success of an Endodontic treatment relies on the position and morphology of root canals. It is important for a clinician to be familiar with the canal morphology to negotiate and thereby filling the canals with an inert material. But, the possibility of negotiating the canals with the use of conventional technique alone is difficult. Hence, careful examination with the use of advanced techniques to enhance vision is required to minimize the rate of treatment failures. To compare the efficiency of three methods Cone-Beam computed Tomography (CBCT), clinical analysis, AND Dental Loupes in detecting the MB2 canal in maxillary first molars.One hundred and fifty extracted intact permanent molars were collected. Two examiners i.e., one Endodontist and a Radiologist examined CBCT images of teeth for the number and position of root canals. The first stage included unaided examination using an explorer and K- files. While those teeth that were failed to locate the canals were examined using dental loupes for better magnification. The results were analyzed by McNemar's tests with Bonferroni correction, and Chi-square test using SPSS software v21.Among 150 extracted teeth that were compared,MB2 was detected using CBCT in around 68% of the teeth, while with the use of naked eye and dental loupes, it was found to be around 30% and 66% respectively and the difference in the detection rates was statistically significant.With the view of the parameter under consideration, CBCT has high detection rates followed by dental loupes and naked eye vision. The efficiency of CBCT scans and dental loupes in detecting a second mesio-buccal canal, thus making it more likely to be treated by the clinician.

Municipal Solid Waste Analysis: Case Study on Gorakhpur City, Uttar Pradesh, India

City sanitation plans are strategic planning processes for city wise sanitation sector development. Exponential increase in population and rapid economic development led to an increase in generation of municipal solid waste (MSW) which impacts the sanitation of a city. Also, emission of toxic gases from MSW dumpsites are the main threat to the environment and public health. In the present study, data regarding solid waste management has been collected and studied the current scenario of the municipal solid waste system of Gorakhpur city, Uttar Pradesh, India. MSW composition, physical and chemical analysis has been performed and Methane gases (CH4) generated from MSW of the city is quantified using LandGEM 3.02. Waste composition shows that city generates paper (6.33%), organic matter (56.1%), wood (1.36%), textile (3.73%), plastic (1.11%), Rubber (0.56%), glass (1.6%) and inert material (29.17%). With the same rate of MSW generation, CH4 emission will amount to 6.6X103 Mg/yr, 1.9x104 Mg/yr of CO2 and 4.33x101 Non methanic organic carbon (NMOC) by 2050. MSW analysis resulted in high moisture content of 35 -40% and organic matter of 56.1%. Based on the physio chemical analysis, suitable waste to energy option that could be adopted are biogas generation and vermi composting from the biodegradable component of MSW. Rest 36% of non-biodegradable part of MSW could be converted to Reduced Derived Fuel (RDF).

Towards Efficient Use of Cement in Ultra High Performance Concrete

This paper presents an investigation on substituting the cement content with an inert material, in a typical locally produced UHPC mix. A structured literature review was performed to enrichen the discussion and to benchmark the results towards already reported investigations in the research society. Investigations on cement substitution in UHPC are frequently reported. However, usually the cement is substituted with other binding materials – often pozzolanic by-products from other industries. Reports from investigations on the use of inert materials for cement substitution in UHPC seem scarce. An experimental program that included a total of 210 test specimens was executed. This program included evaluating several questions embedded to the problem on how to substitute cement while keeping all other variables constant. It is concluded that up to 40% of the cement can be substituted with an inert material, without significantly changing the flexural tensile strength or compressive strength of the hardened UHPC. Two preconditions were caretaken: the particle packing was maintained by securing that the substitution material had a Particle Size Distribution (PSD) near identical to the cement and that the water balance was maintained through preconditioning of the substitution material. Suggestions are made for improving benchmarking.

ReForm - Growing Architecture

<p>Over the past decade robotic fabrication in architecture has succeeded where early digital architecture has fallen short: in the synthesis of the immaterial logic of computers and the material reality of architecture. In light of this new/profound shift architectural theorist and historian of the ‘Digital Turn’ - Mario Carpo argues: ‘We no longer are witnessing the delayed modernization of an industry, but rather an historic departure: the modern division between intellectual work and manual production, between design and realization and manual production. Through this we see traditional modes of design becoming obsolete’. The increasing power of digital design software, the widespread availability of digital fabrication tools, and the growing complexity of our built environment, are in stark contrast to the inefficient techniques that currently hinder today’s construction industry. Furthermore, the utilisation of concepts from nature including biomemesis, biophilia, swarm tectonics, as well as cross-disciplinary influences - from the film industry to social sciences and artificial intelligence - has contributed significantly to the depth of change in the tools, and their subsequent delivery of, architecture. Using nature and biological paradigms as a key influence for the work (specifically biological systems as defined by Menges, Wienstock and others) the thesis asks the question: How can biological theories on growth disrupt inert material perception within the discourse of 3D-printing architecture? It seeks to consider a design and fabrication process that allows the dynamic potential found in natural systems (patterns, forms, behaviours, organisation) to design and build with far more complexity and sophistication. Such work could fore front notions of growth, evolution and natural forms of optimization compared to the current post industrialised notions of beauty. New computing capacity and assembly efficiencies should over time produce more advanced structures than are possible with current technologies. The researcher is ‘aware’ of the range of fabrication methods available to the industry, firstly the invention of Computer Numerical Control (CNC) known primarily as a ‘subtractive method’ of machining and additive manufacturing machines (3D printers) by Charles Hull (1984) which revolutionized rapid prototyping throughout the automotive, aeronautic, and design industries. The application of additive manufacturing workflows - in particular to the architectural field - holds significant potential to provide a fabrication method for the complex geometrical forms that substantiate the parametric design paradigm. However, contemporary attempts in mass fabrication of computer generated componentry are still costly in terms of practice, investment, and time... They are also complex in terms of assembly and co-ordination. Using customized CAD/CAM workflow the author speculates a self-assembling ‘4-D’ architecture. As a piece of explorative design research, the thesis focuses primarily on the underlying philosophy and design methods, and looks to offer up a series of tectonic iterations that integrate form, surface and structure. These iterations have been designed and developed through complex surface pattern projection, a speculative technique developed by the author. It allows a use of direct additive 3d print to surface and enables a prototype fabrication system. This prototype system results in the production of self-assembling tension based membrane surface structures. These structures could, for example, be used for rapid deployment construction scenarios. (see final Design Research). Resin-impregnation patterns are applied to 2-D pre-stretched form-active tension systems to induce 3-D curvature upon release. Form-finding is enabled through this method based on materials’ properties, organization and behavior. A digital tool is developed in the CAD environment that demonstrates the simulation of material behavior and its prediction under specific environmental conditions. The methodology follows a systematic design-led research approach, in which physical form finding techniques, developed throughout the 19th and 20th centuries, are digitized via parametric 3D modelling software. Extensive physical modelling and analysis is conducted into a biomimetic approach to the design of fabric tensegrity surface structures, and their CNC fabrication potential explored. This research demonstrates the association between geometry and material behavior, specifically the elastic properties of resin impregnated Lycra membranes, by means of homogenizing protocols which translate physical properties into geometrical functions. The work challenges the shifting role of the architect from that of an assembler of inert (discrete) material parts towards that of ‘an orchestrator of material effects’. This shift in role is enabled through the affordances of computational design tools, and emerging fabrication methods. Conclusions are drawn from the physical and digital explorations which redefine generative material-based design computation, supporting a synergetic approach to design integrating form, structure, material and environment. How can biological theories on growth disrupt inert material perception within the discourse of 3D-printing architecture?</p>

ReForm - Growing Architecture

<p>Over the past decade robotic fabrication in architecture has succeeded where early digital architecture has fallen short: in the synthesis of the immaterial logic of computers and the material reality of architecture. In light of this new/profound shift architectural theorist and historian of the ‘Digital Turn’ - Mario Carpo argues: ‘We no longer are witnessing the delayed modernization of an industry, but rather an historic departure: the modern division between intellectual work and manual production, between design and realization and manual production. Through this we see traditional modes of design becoming obsolete’. The increasing power of digital design software, the widespread availability of digital fabrication tools, and the growing complexity of our built environment, are in stark contrast to the inefficient techniques that currently hinder today’s construction industry. Furthermore, the utilisation of concepts from nature including biomemesis, biophilia, swarm tectonics, as well as cross-disciplinary influences - from the film industry to social sciences and artificial intelligence - has contributed significantly to the depth of change in the tools, and their subsequent delivery of, architecture. Using nature and biological paradigms as a key influence for the work (specifically biological systems as defined by Menges, Wienstock and others) the thesis asks the question: How can biological theories on growth disrupt inert material perception within the discourse of 3D-printing architecture? It seeks to consider a design and fabrication process that allows the dynamic potential found in natural systems (patterns, forms, behaviours, organisation) to design and build with far more complexity and sophistication. Such work could fore front notions of growth, evolution and natural forms of optimization compared to the current post industrialised notions of beauty. New computing capacity and assembly efficiencies should over time produce more advanced structures than are possible with current technologies. The researcher is ‘aware’ of the range of fabrication methods available to the industry, firstly the invention of Computer Numerical Control (CNC) known primarily as a ‘subtractive method’ of machining and additive manufacturing machines (3D printers) by Charles Hull (1984) which revolutionized rapid prototyping throughout the automotive, aeronautic, and design industries. The application of additive manufacturing workflows - in particular to the architectural field - holds significant potential to provide a fabrication method for the complex geometrical forms that substantiate the parametric design paradigm. However, contemporary attempts in mass fabrication of computer generated componentry are still costly in terms of practice, investment, and time... They are also complex in terms of assembly and co-ordination. Using customized CAD/CAM workflow the author speculates a self-assembling ‘4-D’ architecture. As a piece of explorative design research, the thesis focuses primarily on the underlying philosophy and design methods, and looks to offer up a series of tectonic iterations that integrate form, surface and structure. These iterations have been designed and developed through complex surface pattern projection, a speculative technique developed by the author. It allows a use of direct additive 3d print to surface and enables a prototype fabrication system. This prototype system results in the production of self-assembling tension based membrane surface structures. These structures could, for example, be used for rapid deployment construction scenarios. (see final Design Research). Resin-impregnation patterns are applied to 2-D pre-stretched form-active tension systems to induce 3-D curvature upon release. Form-finding is enabled through this method based on materials’ properties, organization and behavior. A digital tool is developed in the CAD environment that demonstrates the simulation of material behavior and its prediction under specific environmental conditions. The methodology follows a systematic design-led research approach, in which physical form finding techniques, developed throughout the 19th and 20th centuries, are digitized via parametric 3D modelling software. Extensive physical modelling and analysis is conducted into a biomimetic approach to the design of fabric tensegrity surface structures, and their CNC fabrication potential explored. This research demonstrates the association between geometry and material behavior, specifically the elastic properties of resin impregnated Lycra membranes, by means of homogenizing protocols which translate physical properties into geometrical functions. The work challenges the shifting role of the architect from that of an assembler of inert (discrete) material parts towards that of ‘an orchestrator of material effects’. This shift in role is enabled through the affordances of computational design tools, and emerging fabrication methods. Conclusions are drawn from the physical and digital explorations which redefine generative material-based design computation, supporting a synergetic approach to design integrating form, structure, material and environment. How can biological theories on growth disrupt inert material perception within the discourse of 3D-printing architecture?</p>

RECYCLING OF WASTE SLUDGE FROM WWTP "GORIĆ" VALJEVO USING THE PROCESS OF STABILIZATION AND SOLIDIFICATION

The efficiency of wastewater treatment is not only measured by the quality of treated wastewater, but also by the efficiency of treatment and permanent disposal of sludge that is separated. In addition to harmless, the sludge also contains hazardous substances that are released from wastewater during treatment. This work aims to obtain a neutral and harmless product by treating waste sludge with a stabilization and solidification process using modified MID-MIX technology. Physico-chemical analysis has shown that the obtained solidification or neutral, completely inert material, which has a use-value, can be safely disposed of in a sanitary landfill following EU (European Union) regulations. In terms of chemical composition, it is a mixture of crystal-bound organo-calcium, hydrophobic salts with a low moisture content of 5.8%. The results show that the method is the most environmentally friendly and most economical for the treatment of sludge, which can be applied to other types of waste with minor modifications.

Aspects of Reversibility and Energy Efficiency of Prefabricated Straw Structures – Guidelines for Sustainable Design of Architectural Interventions of 21st Century

Architectural space of the 21st century confirms, for the umpteenth time that, architecture is a personified image of society: The products of architectural interventions are the final creations in time and space. The whims of the market, the linear economy model, and users' pluralistic needs generated by cultural preferences mutually develop "white elephants" - inert material, useless and expensive to deconstruct. In response to social, environmental, climate, and economic changes, the construction sector needs to revalue existing construction techniques. The lack of broader application of the circular economy model, the use of inorganic materials and chemical bonds in architectural structures, due to the loss of cultural significance or the appearance of natural disasters, are deprived of their function and produce a large amount of waste. Therefore, the reuse of organic materials derived from renewable energy sources is becoming essential for pushing further the boundaries of reversible design and energy efficiency in architectural interventions. Limits of use of the old – new materials - compressed straw are defined by comparing the results of thermal properties of the building envelope elements - U and R values and levels of reversibility through two opposite approaches to construction, on the example of the conceptual design of a housing unit affected by natural disasters. Analysing the three levels of reversibility that 21st century buildings should possess, given the existing research, the material level limit is shifted in terms of returning to nature with potentially zero environmental waste. Comparing the results of the R values of prefabricated straw structures with the R values of materials predominantly used in architectural interventions raises awareness of the importance and benefits of using compressed straw in architectural envelopes. Existing design parameters of straw structures are optimized by valorising the importance of local climate and materials used. The interaction of native - cellulosic materials breaks down dogmas related to this material and generates the architectural language of reversible and energy-efficient architectural straw products.