Investigation of the Technological Possibility of Laser Hardening of Stainless Steel 14Cr17Ni2 to a Deep Depth of the Surface

The article presents the results of a research of the process of laser hardening of steel 14Cr17Ni2 (AISI 431) by radiation of a high-power fiber laser LS-16. Assessment of the theoretically possible maximum depth in laser processing without additional beam transformations, the use of additional coatings and devices were shown. The results of experiments on increasing the depth of the hardened layer during laser processing by using scanning of the laser beam and optimally selected mode parameters without scanning are demonstrated. The influence of the number of passes on the depth of the hardened layer is investigated. The microstructure of hardened samples was studied and quantitative estimation of structural components was carried out. The microhardness of hardened samples at different modes of laser hardening was measured.

Study of possibility of obtaining alternative binders from production wastes for filling man-caused voids

Basic scientific and practical results of the study of possibility of obtaining alternative binders from production wastes to fill man-made voids at underground ore mining are presented. The objective of the study was to determine the technological possibility and economic feasibility of using available low-active substances as substitutes for expensive and scarce cement. It was shown that it is possible to obtain a binder from dolomite wastes, equivalent in properties to cement, which makes it possible to meet the demands of environmentally correct ore mining technologies. It has been established that hardening mixtures based on dolomites and enrichment tailings are only 8-22% inferior in strength to mixtures with standard cement and are suitable without restrictions for the construction of nature protection massifs in mine workings. Recommended activation of wastes increases the strength of the hardening filling mixture by 15-20% in comparison with the basic technology. With additional preparation in activators, a fundamental change in the quality of dolomite products is possible. The use of wastes in the production of a hardening mixture will free up the land occupied by storage facilities and organize the production of competitive products. Alternative binders and inert materials are recommended for use.

Inventing the Recording

Inventing the Recording: The Phonograph and National Culture in Spain, 1877–1914 focuses on the decades in which the recording went from technological possibility to commercial and cultural artifact, and it does so through the analysis of a specific and unique national context: Spain. It tells the stories of institutions and individuals in the country, discusses the development of discourses and ideas in close connection with national concerns and debates, and pays close attention to original recordings from this era. The book starts with the arrival in Spain of notices about Edison’s invention of the phonograph in 1877, followed by the first demonstrations (1878–1882) at the hands of scientists and showmen. These demonstrations greatly stimulated the imagination of scientists, journalists, and playwrights, who spent the rest of the 1880s speculating about the phonograph and its potential to revolutionize society once it was properly developed and marketed. The book then moves on to analyze the “traveling phonographs” and salones fonográficos of the 1890s and early 1900s, with phonographs being paraded around Spain and exhibited in group listening sessions in theaters, private homes, and social spaces pertaining to different social classes. It finally covers the development of an indigenous recording industry dominated by the so-called gabinetes fonográficos: small businesses that sold imported phonographs, produced their own recordings, and shaped early discourses about commercial phonography and the record as a commodity between 1896 and 1905.

Technologically Sustainable Route for Metals Valorization from Jarosite-PbAg Sludge

By-products from zinc hydrometallurgy are classified as hazardous waste with strong leaching toxicities. Even though numerous research papers are dedicated to valorizing valuable metals in it, the primary management route is still disposal or partial reuse, such as the Waelz process. Presented experimental research investigates possibilities of sulfidization and further processing as a technologically sustainable route for valuable metals valorization from non-standard jarosite-PbAg sludge. The comprehensive thermodynamic analysis was done by HSC Chemistry®, through optimizing process parameters, i.e., temperature, sulfur addition, and selection of possible additives. Technological possibility of magnetic separation, flotation, and smelting of sulfidized material was also investigated; the results were below the values that allow practical application, due to the obtained texture of sulfidized jarosite, which does not allow the liberation of minerals. Smelting tests were performed on sulfidized jarosite with sulfur and without and with carbon as additive. By smelting sulfidized jarosite-PbAg sludge with added carbon in sulfidization stage at 1375 °C, obtained products were matte, slag, raw lead, and dust in which base, critical, and slag forming components were valorized. Valuable metals were concentrated in smelting products so as to enable further processing, which also could be interesting in the case of treatment of complex, polymetallic, and refractory primary materials, which represent a significant contribution to the circular economy.

A USE OF PENTOSAN-CONTAINING FRACTION OF NEUTRAL LIGNOSULFONATES FOR OBTAINING FURANE DERIVATIVES

The article describes the technological possibility and gives a conditional scheme of obtaining, based on the carbohydrate part of neutral lignosulfonate, useful products such as furfurol, furan, tetrahydrofuran, properties which have a number of significant physicochemical differences from the properties of lignosulfonate obtained as a result of sulphite brews. The article discusses features of aromatic and carbohydrate constituents of neutral lignosulfonates, monomeric units of aromatic part, structure of polysaccharide components of carbohydrate part, as well as lignocarboxylic matrix characterizing their combination in macromolecule of lignosulfonate. On this basis, the possibility of using neutral LSTs as pentose-containing raw materials was studied and experimentally realized. The experimental part of the article proposes a method of fractionation of lignosulfonates, in our case lignosulfonates of the neutral-sulfite method of delignification of wood raw materials. Samples of the neutral lignosulfonate that was the subject of the study were subjected to alkaline hydrolysis, after which fractionation was carried out by exclusive chromatography or gel filtration on Sephadex grade 100. Water was used as eluent. Fractions were taken by volume, the composition of fractions, both aromatic and carbohydrate, was determined by UV spectroscopy. The criterion for the composition of the fraction was the presence or absence of peaks on the spectrogram in the wavelength region characteristic of the hydroxyl phenolic groups of the aromatic part of neutral lignosulfonates and monosaccharides of the pentose class. The combined polysaccharide fractions represented mainly by xylanes (pentosans) were extracted into an organic solvent, followed by distillation and boiling of the furan-containing compounds. Material balance of the process of producing furan derivatives based on pentose-containing component of neutral lignosulfonates is drawn up.

An Analysis of Privacy Language in the Scholarly Literature on Mental Health Apps

This chapter charts the language of privacy in published scholarship on mental health apps. What definition of privacy is assumed? What meanings of privacy are deployed in the research about mental health apps? Using a qualitative thematic approach, this analysis shows that privacy language can be understood as occurring in three phases: Phase 1: Discourse of Technological Possibility; Phase 2: Discourse of Privacy Challenges and Threats; and Phase 3: Discourse of Advocacy. The authors discuss each of these phases and propose a more critical discourse of privacy by identifying the issues inherent in understanding privacy as security.

An Analysis of Privacy Language in the Scholarly Literature on Mental Health Apps

This chapter charts the language of privacy in published scholarship on mental health apps. What definition of privacy is assumed? What meanings of privacy are deployed in the research about mental health apps? Using a qualitative thematic approach, this analysis shows that privacy language can be understood as occurring in three phases: Phase 1: Discourse of Technological Possibility; Phase 2: Discourse of Privacy Challenges and Threats; and Phase 3: Discourse of Advocacy. The authors discuss each of these phases and propose a more critical discourse of privacy by identifying the issues inherent in understanding privacy as security.

MARVEL mission proposal: The latest update

<p>Following the recommendations of the 2019 CNES scientific prospective seminar, a pre-Phase-A study was launched in January 2020 at CNES on the concept of the MARVEL mission. MARVEL proposed to carry out in a single mission the survey of earth mass transfers with increased precision and the determination of the terrestrial reference system, thanks to two constellations of satellites at 500 and 7000 km altitude equipped with "radial" measurement links between the constellations. The results of the first six months of this pre-Phase-A will be presented.</p> <p><br />Our work has mainly focused on two axes:<br />- a closed-loop numerical simulation to assess the scientific performance of a large number of orbital configurations, including radial links but also "Bender" and "Pendulum" configurations;<br />- a technological study to bring the precision of a laser inter-satellites chronometry link to the micrometric level.</p> <p><br />This work has, so far, highlighted:<br />1 / the poorer performance for the determination of the gravity field of the "radial" type measurements compared to a "pendular" configuration in which the satellites are at the same low altitude with the ascending nodes of their orbits slightly offset so that the measurements between the spacecraft are alternatively oriented to the right and to the left of the track, thus improving the geometric configuration compared to an in-line pair of satellites;<br />2 / the technological possibility of achieving by chronometric laser link, over a few hundred or even a few thousand km, the precision of 1 micrometer in distance and 0.1 micrometer/s in relative velocity (which is necessary for the achievement of the scientific objectives).</p> <p><br />The pre-Phase-A MARVEL, taking into account the "Mass Change" studies on the NASA side and "NGGM" on the ESA side, is therefore reoriented towards a "pendulum" type mission, abandoning the objective of determining jointly the terrestrial reference system.</p>

Conclusion

This chapter concludes that unbridled technology is catastrophic to man's future. But it is equally obvious that what man has learned about the uses of technology should not, cannot ever be lost. Yet acknowledging the need to be wary is not the same as using caution to found a politics of dismantling in the present. In the twenty-first century, a time and place far from the Maine conversations of the Boggses and Paines, there must be a willingness to lose the machines. To decide in advance not to lose them is only the least objectionable version of the ambivalent formula that technology should not be unbridled, and that people want something other than a technological revolution, but the value of certain machines cannot ever be lost. It was a powerful ambivalence in its moment, because it called out unbridled exploitation but held firm to technological possibility. But at this late date, when tech firms and state agents hold all the codes, something still more urgent is required: to sweep past noncommittal logics, to risk relinquishing any use of any machine, and to move in groups toward more concrete practices of technological responsibility through dismantling.