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Laser additive manufacturing is attractive for the production of complex, three-dimensional parts from metallic powder using a computer-aided design model 1 – 3 . The approach enables the digital control of the processing parameters and thus the resulting alloy’s microstructure, for example, by using high cooling rates and cyclic re-heating 4 – 10 . We recently showed that this cyclic re-heating, the so-called intrinsic heat treatment, can trigger nickel-aluminium precipitation in an iron–nickel–aluminium alloy in situ during laser additive manufacturing 9 . Here we report a Fe19Ni5Ti (weight per cent) steel tailor-designed for laser additive manufacturing. This steel is hardened in situ by nickel-titanium nanoprecipitation, and martensite is also formed in situ, starting at a readily accessible temperature of 200 degrees Celsius. Local control of both the nanoprecipitation and the martensitic transformation during the fabrication leads to complex microstructure hierarchies across multiple length scales, from approximately 100-micrometre-thick layers down to nanoscale precipitates. Inspired by ancient Damascus steels 11 – 14 —which have hard and soft layers, originally introduced via the folding and forging techniques of skilled blacksmiths—we produced a material consisting of alternating soft and hard layers. Our material has a tensile strength of 1,300 megapascals and 10 per cent elongation, showing superior mechanical properties to those of ancient Damascus steel 12 . The principles of in situ precipitation strengthening and local microstructure control used here can be applied to a wide range of precipitation-hardened alloys and different additive manufacturing processes. A Damascus-like steel consisting of alternating hard and soft layers is created by using a laser additive manufacturing technique and digital control of the processing parameters.

On Apr 25, 1925, the first Calling of an Engineer ceremony was performed in Montreal, Canada. Six engineers pledged themselves to uphold the ethical standards and kindred spirit of their vocation. Historical documentation of the ceremony states that the Obligation, as it was called, was taken over \"ancient landmarks\" of the engineering profession: a machinist's hammer, a blacksmith's anvil, and a chain, all of \"honorable working record,\" tried and tested in service. Rings made of iron, which had been cold-worked by convalescing World War I veterans, to be worn on the little finger of the working hand, would serve as a reminder of the serious responsibilities that engineers take on. A week later, 107 more engineers took the Obligation in Toronto. Thereafter, the ceremony spread across Canada.

Refining predicted protein structures with all-atom molecular dynamics simulations is one route to producing, entirely by computational means, structural models of proteins that rival in quality those that are determined by X-ray diffraction experiments. Slow rearrangements within the compact folded state, however, make routine refinement of predicted structures by unrestrained simulations infeasible. In this work, we draw inspiration from the fields of metallurgy and blacksmithing, where practitioners have worked out practical means of controlling equilibration by mechanically deforming their samples. We describe a two-step refinement procedure that involves identifying collective variables for mechanical deformations using a coarse-grained model and then sampling along these deformation modes in all-atom simulations. Identifying those low-frequency collective modes that change the contact map the most proves to be an effective strategy for choosing which deformations to use for sampling. The method is tested on 20 refinement targets from the CASP12 competition and is found to induce large structural rearrangements that drive the structures closer to the experimentally determined structures during relatively short all-atom simulations of 50 ns. By examining the accuracy of side-chain rotamer states in subensembles of structures that have varying degrees of similarity to the experimental structure, we identified the reorientation of aromatic side chains as a step that remains slow even when encouraging global mechanical deformations in the all-atom simulations. Reducing the side-chain rotamer isomerization barriers in the all-atom force field is found to further speed up refinement.

The relevance of the study is determined by the fact that green industry is a new area of the economy aimed at preserving the well-being of society through the efficient use of Earth resources. The development of humankind is impossible without the impact on the environment and the use of natural resources: factories are built, waste is incinerated, minerals are mined, forests are cut, and smoking factories are launched. Almost all human actions affect the ecosystem of the Earth; hence, the article discusses whether it is possible to make this impact less harmful. Studies are given on the harm caused by large-scale production to the environment and how to reduce it; how the environmental policy of cities is changing and enterprises are transformed; what is a ‘green industry’ and how to organize production according to its principles. The empirical basis of the study is the research report of the World Health Organization; American scientists and experts of the Swiss company IQAir, the data of the rating of the US Blacksmith Institute (Pure Earth NGO) for the study of the toxic cities, as well as Eric Hobsbawm’s scientific works. The practical significance of the research is aimed at the rational use and organization of work with natural resources, their economical consumption, the use of environmentally friendly technologies in production and in life, and the creation of sustainable conditions for investment in such projects not only by the government authorities, but also by the private sector.

Chromium (Cr) is used as a mixture to improve strength and corrosion resistance. Milling and welding processes can expose workers to Cr through dermal exposure and inhalation. Cr exposure can be determined by urine testing. The purpose of this study was to analyze the concentration of Cr in urine (UCr) of workers. This study was carried out using a cross-sectional method. Sampling was conducted in the village of Mekarmaju, Bandung, Indonesia. The number of respondents included 30 blacksmiths, and the control group comprised 10 people who were not blacksmiths. Cr 6+ exposure was measured using a personal sampling pump placed on the collar of the worker’s shirt as a breathing zone and then analyzed using a UV–visible spectrophotometer. UCr was measured with a graphite furnace atomic absorption spectrophotometer. The measured Cr 6+ concentration in the exposed working area ranged from 0.03 to 0.63 mg/m 3 , whereas that in non-exposed area ranged from 0.02 to 0.04 mg/m 3 . Results showed that 16 out of 30 blacksmiths had a UCr concentration above the biological exposure index (BEI) value, 21 had a higher value than the threshold limit value (TLV), and 22 had hazard index (HI) values > 1, which indicated that Cr has a hazardous potential in the body. The analysis of the exposed and control groups showed a significant difference with a p value of 0.000 for TLV, chronic daily intake, and UCr. These results clearly showed that Cr 6+ exposure may harm the health of these workers in the future. The results obtained in this study can be used to promote workers’ awareness on the potential health risk caused by Cr 6+ exposure in the working environment.

The current work presents the results of neutron activation analysis applied to determine the elemental composition of ancient metallurgical slags found by archaeologists in the medieval settlement “Eski Khovos” in Uzbekistan. In Uzbekistan, archaeological artifacts, including products of archaeometallurgy, are predominantly studied using traditional descriptive techniques. Two slag-like object samples and three fragments of clay furnace walls were irradiated by thermal neutrons at the research reactor of the Institute of Nuclear Physics of Uzbekistan. The comparative analysis method enabled the identification of up to 34 different chemical elements in these samples (As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Ga, Hf, K, La, Lu, Mn, Mo, Na, Nd, Rb, Re, Sb, Sc, Sm, Sn, Sr, Ta, Tb, Th, U, W, Yb, Zn). The findings of this study suggest that the fragments are remnants of blacksmithing slags. The established methods of neutron activation analysis and processing of characteristic gamma spectra of activated samples hold significant interest for archaeologists of Uzbekistan, as they provide valuable new insights into the provenance, production techniques, and technological advancements of the archaeological artifacts, which in turn contribute to a better understanding of the region's historical and cultural development.

The attendant effects of urbanization on the environment and human health are evaluable by measuring the potentially harmful element (PHE) concentrations in environmental media such as stream sediments. To evaluate the effect of urbanization in Osogbo Metropolis, the quality of stream sediments from a densely-populated area with commercial/industrial activities was contrasted with sediments from a sparsely-populated area with minimal anthropogenic input. Forty samples were obtained: 29 from Okoko stream draining a Residential/Commercial Area (RCA, n  = 14) and an Industrial Area (IA, n  = 15), and 11 from Omu stream draining a sparsely-populated area (SPA). The samples were air-dried, sieved to < 75 micron fraction, and analysed for PHEs using inductively-coupled plasma atomic emission spectrometry (ICP-AES). Index of geoaccumulation (I geo ), pollution index (PI), ecological risk factor (Er) and index (ERI) were used for assessment. Inter-elemental relationships and source identification were done using Pearson’s correlation matrix and principal component analysis (PCA). PHE concentrations in the stream sediments were RCA: Zn > Pb > Cu > Cr > Sr > Ni > Co, IA: Zn > Cr > Ni > Co > Pb > Cu > Sr and SPA: Zn > Co > Cr > Cu > Sr > Ni > Pb. I geo calculations revealed moderate-heavy contamination of Cu, Pb and Zn in parts of RCA, moderate-heavy contamination of Zn in IA while SPA had moderate contamination of Co and Zn. PI values revealed that stream sediments of RCA are extremely polluted, while those of IA and SPA are moderately and slightly polluted, respectively. The pollution of the stream sediments in RCA and IA is adduced to anthropogenic activities like vehicular traffic, automobile repairs/painting, blacksmithing/welding and metal scraping. In SPA however, the contamination resulted from the application of herbicides/fertilizers for agricultural purposes.

This study examines the cultural livelihood of Kogi State and its effects on the environment. The study describes some of the cultural livelihood practices found in Kogi State, considering the contemporary condition of cultural livelihood and its effects on the environment. Secondary and primary data were employed, which include archives and internet search engines. Using a 4-stage sampling procedure, data were collected from a 120-person sample through an interview, field observation, a focus group discussion, and a questionnaire. Descriptive statistics using frequencies, percentages, and charts were used for the analyses. The results were compiled using the Statistical Package for Social Sciences (SPSS). Findings show that about 85% of the participants discovered crop farming, arable farming, weaving, blacksmithing, fishing, and festivals of harvest, such as the New Yam Festival, among others, as the predominant cultural livelihoods. The local farming implements were made of local materials, like stones and wood. They have indigenous crop production, protection, and harvest techniques. The farming tools were economical in terms of labor, affordability, and time savings in the subsistence farming system. The study discovered that cultural livelihoods are 4% very efficient and 56% on the verge of extinction. Analyses of the effect of cultural livelihood show that 78% have a high negative effect on the economic environment, 57% have a moderate negative effect on the social environment, 51% hurt the political environment, and 22% have a low negative effect on the political environment. The intervention of the various tiers of government with the cooperation of the various communities is needed for the provision of a conducive environment for the practice of cultural livelihood, particularly in the aspect of insecurity. Adequate provision of modern equipment, funding, and social welfare services is also recommended to enhance cultural livelihoods.

This study investigates the effect of using steel filings from the waste of blacksmiths workshops on the clay bricks mixture to improve the bricks’ compressive strength. On the other hand, this process can reduce workshops’ waste by recycling it to preserve the resources and achieve sustainability. Adding steel filings to the mixture of red clay bricks was in different proportions by weight (1%, 2%, 3%, and 4%) on prototype bricks produced in a lab. Moreover, it aims to increase the effectiveness of clay bricks used in load-bearing walls, which can be used extensively in economical housing to reduce the cost if its strength increases by utilizing it in the load-bearing walls system instead of skeleton. The experimental approach was adopted to reach conclusions, as it is the appropriate approach suitable for this research. Before and after adding steel filings, many properties were tested, such as dimensions, weight, density, water absorption, and compressive strength. It is observed that on increasing the steel filings ratios by the mixture’s weight, the prototypes’ compressive strength also increases. The highest percentage of increased compressive strength occurred for the specimen with 3% steel filings by the mixture’s weight is (84%).

Blacksmiths manufacture farm equipment that still uses conventional systems in their production. The fabrication process goes through the heating stage of steel to a temperature of 850°C as the primary raw material (carbon steel). Heating aims to make the steel easy to shape into farm tools. Conventional furnace designs, such as those at blacksmiths in the Pandak area, Bantul, still use an open system, causing air pollution around the workplace. This research modernizes a blacksmith furnace for iron with multi-air flow and dust filtration systems. Total dust testing uses SNI 7119-3:2017 standards. The results were that the burning stove has three variations of airflow, which can be adjusted to the type of work to save wood charcoal fuel by around 30%. A combustion furnace with an ash filtration system can minimize pollutant particles around the work environment from 3.99 mg/m 3 to 0.024 mg/m 3 . Modernization of furnaces has reduced air pollution by up to 99%.