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Scientific data available on the internet is rarely labelled. Most popular research paper repository sites contain papers without any annotation for grouping data. Classification of text via words, sentences and even paragraphs has become a key resource for a lot of industries looking to help their computers understand human language – the next stage in Artificial Intelligence. Using valuable Computational Linguistics ideas, some industrial applications have been able to streamline their processes to effectively and efficiently process and interpret language data. Continuing in this trend, in this paper, we aim to effectively clustering scientific research papers into topic-based differentiators, in the most efficient manner. Using multiple algorithms that have revolutionized the industry in the previous years, we compute over 800,000 entries of scientific research articles across 200+ domains that have been uploaded to accurately predict domains for each of these articles. We use clustering techniques like the K-Means algorithm to derive the topics for these papers with an accuracy of nearly 80%. We also use BERT to create topic clusters that generate topics based on frequently occurring contexts within the text. Beyond BERT, we use offspring algorithms that tackle specific, niche issues that BERT does not account for. We also fine-tune the parameters of the algorithms used to generate over 50 stronger topics that more accurately define scientific articles.

The present paper reports on the results of some experiments on the progress of a previous research and describes the production, in single fast firing, of tiles containing 30 wt% of a natural red clay and a mixture of 42 wt% of paper mill sludge and 28 wt% of glass cullet which were coated with a commercial “matt white” glaze. Fired materials were characterized as a function of the top temperature (1090 or 1140 °C) reached during the fast sintering process made in an industrial roller kiln. It is observed that tiles fired at 1090 °C display the best overall performances since the matt glaze well covers the substrate concurring to maintain in line with the official standard for production the mechanical and physical properties of the tiles.

We propose development of an advanced type of "paper transistor" by using carbon-nanotube (CNT) composite papers (CNTCPs) and aim to apply our paper transistors to the construction of logic circuits. It is known that CNTs have many functions such as high electrical and thermal conductivities and metallic and semiconducting properties. Our CNTCP, which has various functions held by CNTs despite being paper, can be fabricated easily by scooping up and drying materials from a mixture of CNT and pulp (paper materials) dispersions. The CNTs have metallic or semiconducting properties, so metallic and semiconducting CNTCPs can be fabricated. By preparing such CNTCPs and normal paper as an insulator, we can produce the paper transistor. In previous work, we confirmed our prototype paper transistor could operate as a p-type transistor. However, the sample had problems, e.g., the internal resistance was rather high. In this study, we aim to overcome the problems by using a novel method for making the CNTCP. As the result of experiments, we succeeded in obtaining new paper transistors with better performance in comparison with the previous one. Moreover, we succeeded in finding a potential use as an n-type paper transistor by using an n-type doping material for semiconducting CNTCPs.

We have developed a unique “paper transistor” comprised of carbon nanotube (CNT) composite papers. CNTs have recently attracted much research attention in the nanotechnology field due to their many excellent physical properties, including good electrical and heat conductivities, physical strength, and dual semiconducting- and metallic- characteristics. CNTs have great potential for use as many different functional materials. In a previous work, we developed a CNT-composite paper as a new functional material. A normal paper is flexible and can be fabricated and used easily, and we can easily fabricate the CNT-composite paper by mixing pulp with CNTs. The resulting CNT-composite paper has both CNT and normal paper characteristics. In this study, we focused primarily on the dual semiconducting- and metallic- characteristics exhibited by CNTs because we can create paper composites that are both semiconducting and metallic. Our main goal was to develop a field-effect-transistor (FET) using semiconducting- and metallic- CNT-composite papers. A conventional FET has metal, insulator, and semiconductor layers. Our FET also has three layers: the metallic CNT-composite paper is used for gate, source, and drain electrodes as the metal layer; the semiconducting CNT-composite paper is used for a semiconductor as the channel layer; and the normal paper is used as a gate insulator layer. The key point here is that we were able to design and develop an FET using only normal paper and two kinds of CNT-composite paper, without any silicon or semiconductors. After the construction, we measured the electrical conductivity of our FET to test its operation. A drain-to-source current of about 10μA was observed. Moreover, we could control the current flow by controlling the gate voltage. These results demonstrate that it is possible to fabricate a paper FET using only normal paper and two kinds of CNT-composite paper.

Excess sludge generated from wastewater treatment plants (WWTPs) can cause negative impacts on human health, water bodies, aquatic plants, and soil quality. However, the produced sludge could be appropriately managed to obtain various economic and environmental benefits. One of the feasible and practical options of sludge management is the synthesize of biochar via oxygen-limited pyrolysis. The use of biochar adsorbent for pollutant removal offers various advantages such as high adsorption capability, low operating and chemical costs, no production of toxins. Hence, this study addresses the applications of sewage sludge-derived biochar for industrial wastewater treatment. The methods of sludge collection, drying, pulverization, and pyrolysis are illustrated. Biochar characterization methods (SEM, EDX, XRD, and FTIR analyses) and mechanisms of the adsorption process are described. The sludge-derived biochar could be used as an adsorptive material for industrial effluent treatment. Recommendations for future studies that could enhance the adsorption capacity of biochar and modified-biochar are given.

The pyrolysis process of jengkok tobacco is influenced by the quality of the raw material, production machine, process parameters and production yield standards. Optimal process requires efficiency and effectiveness of the usage of energy and machine, because all of those affect the quantity and quality of the end products. The purpose of this study was to determine the effect of energy released and machine performance on the percentage of Jengkok Biochar Yield produced through the pyrolysis process. The primary data was obtained directly from the production process. Variables used were temperature (510°C, 515°C, 520°C) and processing time (30 minutes, 35 minutes, 40 minutes). This study found that the most efficient energy required was at the temperature of 520°C and 35 minutes time period, so that the energy released decreased while the machine performance increased and the % yield was higher.

Surfactants are amphiphilic molecules that have been used in widely used as emulsifier and cleaning agent in various industries. These broad industrial applications made the global surfactant production increased annually. In 2020, the amount of global surfactant production estimated would reach more than 24 million per year. However, the currently used surfactants are synthetically produced from chemical or petroleum-derived products, so it is often toxic and non-biodegradable. Rhamnolipids are “surfactant like” molecules produced by Pseudomonas aeruginosa, which could be alternatives for more environmentally friendly surfactants. The use of rhamnolipids is quite limited due to its expensive production cost. The production cost of rhamnolipid could be reduced using by agro-industrial by-product as a substrate. One of the abundant agro-industrial by-products in Indonesia that can be used as a substrate for rhamnolipid production is Oil Palm Empty Fruit Bunch (OPEFB). This study employed SuperPro Designer v9.5 to performed process simulation and economic assessment of rhamnolipid production using OPEFB as a substrate through two different purification methods, which are solvent extraction and chromatography adsorption. Based on the process simulation that has been done, the process that used adsorption chromatography purification methods more efficient in terms of the usage of the feedstock and energy. The economic assessment also showed that these methods were more profitable and economically attractive, with the value of NPV 11.400.000 USD, IRR 11,64%, and Payback Period 6,21 years.

Ultrasound treatment is one of the known method to obtain the globular microstructure for semisolid processing of aluminum alloys. Notwithstanding the numerous advantages, the main industrial limit of this method is the low service life of the horn due to the combined hot corrosion and erosion phenomena. Various approaches are reported in literature to overcome this problem, but a real satisfactory option does not seem to be available yet. In this paper, the behavior of a H11 tool steel sonotrode coated with a thin layer of TiAlCN is investigated and compared with the performance of an uncoated steel one. The lifetime of the horn was evaluated in terms of effectiveness in semisolid feedstock material preparation. For this purpose, the microstructure of semisolid cast samples obtained after different working times was analyses by optical and scanning electron microscopy. Moreover, melt contaminations due to the probe dissolution were also evaluated. The applied coating exhibited a significant resistance to separate hot corrosion in liquid Al alloy and cavitation erosion phenomena in water. However, the combined effect of the two damaging mechanisms during ultrasound treatment of the molten alloy leaded to coating removal and to a horn consumption comparable to that of bare steel.

Great focus has been directed towards double-layer capacitance and Faradic, redox reactions because of their long device lifetimes and their high power densities, respectively. Our novel approach to combining these mechanisms in a tri-layered composite electrode promises to increase the energy densities of the device, without sacrificing the supercapacitance and the high power densities attributed with it. Initial analysis of the interfacial interactions of graphene oxide (GO) and manganese oxide (MnO2) were promising. This paper aims to further demonstrate the tri-layered composite by forming a layer of reduced graphene oxide (rGO) on MnO2 nanowires and cobalt oxide nanorods. We have successfully created the first of a kind supercapacitor electrode material as a scalable device. In this paper, in addition to analysis of the composite electrode, we present modifications to the traditional electrophoretic deposition process and optimizations to the thermal reduction of GO in order to create rGO surfaces on substrates that are normally difficult to adhere it to.

Graphene is a promising component for next-generation high-performance structural and multifunctional composite materials. Graphene deposited onto nanofibers of high aspect ratio can serve as reinforcement agent for improving ceramic fracture toughness and electroconductivity. It was found that quality and quantity of graphene sheets on the fiber surface essentially depends on the pyrolysis of carbon source conditions such as gas flow, duration, temperature and the composition of the gas mixture. The alumina/graphene composites of 10 and 15 wt% of nanofibers covered by graphene were produced by spark plasma sintering (SPS) at 1380 °C. Both composites show improvement in mechanical and electrical properties as compared to the monolithic alumina. The main advantage of the graphene growth on the fibers surface is a lack of complicated step of constituents mixing. Graphene platelets are believed to act as toughening agents prevailing crack propagation under loading.

In ceramic tile manufacturing industry, the wet process including wet grinding and spray drying, is widely used for preparing granule. However, due to the high energy consumption for the water evaporation in spray dryer, it has become a major problem in wet process. In recent years, there have been vast amount of researches for developing of dry granulation processes in that granule size distributions cause quality problems in the final products.In this research, it is aimed to develop a new production system, called as Semi-Wet Process. The new system consists of a horizontal dryer, dry ball mill, separator and an additional high speed mixture. The raw-materials having low humidity are ground to the required fineness in dry size reduction process. The other components of recipe, that are prepared in conventional wet process, are mixed with the dry prepared powder in the mixing slurry tank. The addition of dry powder reduces the water ratio of final suspension. Hence, the natural gas consumption of the water evaporation in spray dryer is reduced substantially.The industrial application of the developed Semi Wet System was carried out in Kaleseramik Factory in Turkey, where 28% reduction on gas consumption has been achieved.

We introduce a new self-separation of graphene oxide flakes exploiting liquid crystalline phase formation. Moderately concentrated discotic GO aqueous solution spontaneously phase separates into isotropic phase and nematic phase. According to Onsager theory, larger flakes with higher aspect ratio tends to form nematic phase, while smaller flakes remain in isotropic phase. Simple isolation of bottom nematic phase (large graphene oxide; LGO) resulted in the LGO dominant dispersion preparation. We employed this size selection principle to investigate the influence of GO flake size upon the material properties of reduced graphene oxide. The electrical properties of spin cast rGO films are thoroughly investigated in terms of the GO flake sizes in the precursor aqueous dispersions. Interestingly, nitrogen doping in order to inject more electron charge carrier exhibit different behavior following flake size. Therefore, it was experimentally confirmed that quaternary nitrogen doping site acts as the dominant catalytic site in oxygen reduction reaction.

Chemical Vapor Deposition (CVD) is generally utilized for producing large area, good quality graphene films on suitable substrates. Copper (Cu) substrate is used mainly as a substrate and catalyst during graphene synthesis process by CVD method. The purpose of the present work is to investigate the evolution of Cu surface morphology after graphene growth and its influence on grown graphene quality. In this study, graphene was grown using methane as the carbon source at temperature 1040 °C for 5 minutes. Scanning electron microscopy (SEM), Optical Microscopy (OM) and atomic force microscopy (AFM) were utilized to analyze the change of Cu surface morphology after graphene synthesis. Raman spectroscopy was used to characterize the characteristics of grown graphene. SEM and AFM results showed that copper substrate surface morphology was modified after graphene growth associated by formation of large size Cu particles located basically on the surface terraces, resulting in deposition of multilayer, very small graphene domains aligned linearly along rolling marks direction.

Cellulose/silica derived hybrids materials (CSH), functionalized with aluminium, calcium, and propylammonium ions, were tested for their possible use in the removal of arsenic from aqueous solutions with controlled compositions to levels lower than 10 μg As/L. CSH were synthesized by sol-gel method using bleached pulp, as source of cellulose fiber, and tetraethoxysilane (TEOS) as main silica precursor. The silica network, made in situ, contained various anchored cations such as propylammonium (CSH-PA), aluminium (CSH-Al) and, calcium (CSH-Ca). Thin films or mesoparticles of silica were deposited on cellulose fibers as shown by SEM and XRD. These hybrid materials were immersed in controlled ionic strength aqueous solutions with arsenic concentrations lower than 0.2 mg As/L. The best performance was shown by CSH-PA that was able to remove a maximum of 20 % of the total arsenic concentration.

In this work, wastewater from Teva Pharmaceutical Industries Ltd., which comprises several organic and inorganic compounds, was solidified in a geopolymer matrix. The addition of wastewater to the polymerization mixture of fly ash based geopolymers yielded a high compressive strength of 50-75 MPa that is similar to that of wastewater-free geopolymer. The leaching of organic compounds from the matrix was examined and it was found to be negligible, about 0.2%wt, and comparable to the amount that leached from a geopolymer matrix made without wastewater. The results indicate that the immersion temperature and the time of immersion have negligible influences on carbon leaching.