An Eco-Friendly Acid Leaching Strategy for Dealkalization of Red Mud by Controlling Phase Transformation

The alkaline components in red mud represent one of the crucial factors restricting its application, especially for the construction and building industry. The phase state of alkaline components has a significant influence on the dealkalization of red mud. In this work, an environmentally friendly acid leaching strategy is proposed by controlling the phase transformation of red mud during active roasting pretreatment. With a moderate roasting temperature, the alkaline component is prevented from converting into insoluble phases. After acid leaching with a low concentration of 0.1 M, a high dealkalization rate of 92.8% is obtained. Besides, the leachate is neutral (pH = 7) and the valuable metals in red mud are well preserved, manifesting a high selectivity and efficiency of diluted acid leaching. The calcination experiment further confirms the practicability of the strategy in the construction field, where the cementitious minerals can be formed in large quantities. Compared with the traditional acid leaching routes, the diluted acid leaching strategy in this work is acid saving with low valuable element consumption. Meanwhile, the secondary pollution issue can be alleviated. Hence, the findings in this work provide a feasible approach for the separation and recovery of alkali and resource utilization of red mud.

Old trees are perceived as a valuable element of the municipal forest landscape

Urban trees are important to maintain biodiversity and, therefore, need public acceptance. Few studies, however, have addressed the topic of social acceptability of old trees. The aim of this research was to examine city residents’ perception of old trees, including hollow-bearing ones, mainly in the aspect of safety and aesthetics. A total of 448 Warsaw municipal forest’ users expressed their opinions by completing an online questionnaire. Several methods were used to analyse the results of the study: the Chi-square test of independence, the Kruskal–Wallis H test, the Mann–Whitney U test and the Quartimax method of factor rotation analysis. The results revealed a correlation between the frequency of forest visits and the level of sensitivity toward old trees, which translates to less radical notion of danger and less radical decisions about cutting such trees down. Age of the respondents (56+) was a factor contributing to higher willingness to protect and care for old trees. The results also indicated that outdoor activity in the urban forest may increase ancient trees acceptance by developing emotional connection with them, and eventually contribute to their protection.

Relationship Between Gender and Clinician’s Subjective Experience during the Interaction with Psychiatric Patients

Introduction: The clinician’s subjective experience can be a valuable element for diagnosis and treatment. A few factors have been recognized that affect it, such as the patient’s personality, the severity of psychopathology, and diagnosis. Other factors, such as patient’s and clinician’s gender, have not been specifically investigated. The aim of this study is to explore the impact of gender differences on the clinician’s subjective experience in a large sample of psychiatric patients. Methods: The study involved 61 psychiatrists and 960 patients attending several inpatient and outpatient psychiatric settings. The clinicians completed the Assessment of Clinician's Subjective Experience (ACSE) questionnaire after observing each patient for the first time. Results: In multivariate analysis, higher scores on the Difficulty in Attunement (p < 0.001), Engagement (p<0.05), and Impotence (p<0.01) scales were significantly associated with female clinician gender, whereas higher scores on the Tension and Disconfirmation scales were significantly associated with male clinician gender. The scores on all ACSE dimensions were also associated with the severity of psychopathology. Conclusion: The findings suggest that clinician’s gender might affect a clinician’s emotional response toward patients. Specific attention to this issue might be useful in clinical situations, not only in terms of promoting gender-balanced teams but also in terms of enhancing self-observation in clinicians evaluating patients for the first time.

Granatowa? Nie, brunatna

The author of the essay considers Jan Grabowski’s book Na posterunku. Udział polskiej policji granatowej i kryminalnej w zagładzie Żydów [At the Station: The Participation of the Blue Police and Criminal Police in the Extermination of Jews], which presents research into the behavior of Polish policemen toward Jews during the Nazi occupation. The findings reveal that the entire organization—apart from exceptions, of course—behaved terribly. The negative behavior of the policemen went beyond even the attitude imposed by the occupiers. In the essayist’s opinion, a very valuable element of the work is its presentation of the realities of those times on the lower levels of social organization: in villages and in ghettos established in small towns. Grabowski thus made use of material that historians rarely consider. For instance, the duty roster of a police post was as significant to him as the decrees of the authorities. The essayist considers Grabowski’s work to be especially important for having appeared during a time of intense debate over relations between Christians and Jews during the occupation of Poland. The essayist emphasizes the topicality of problems of the past and certain historical publications. The appearance of the book should call into question the traditions and conception of the past to which the police force itself refers.

Mobility of antimony in samples from diverse environmental compartments of Sb mines in Spain: leaching experiments in oxidizing and reducing conditions

&lt;p&gt;Antimony (Sb) is a valuable element, exploited for diverse applications including flame retardants, munitions, batteries, glasses, and industry for diodes. However Sb is also a toxic metalloid, often associated with other harmful elements (arsenic, lead, mercury&amp;#8230;) in mining sites. The biogeochemical behavior of Sb remains poorly documented, and data must be acquired in order to elaborate solid environmental studies related with Sb mining. Here, the mobility of Sb from solid phases present in former mining sites was assessed through leaching experiments performed in oxidizing or reducing conditions. Five Sb mines located in South-Central Spain were considered: La Nazarena, Accesos, Balanzona, Pilar, and Susana mines. Rock samples were analysed by X-ray diffraction, confirming that the main Sb carrier was stibnite (Sb&lt;sub&gt;2&lt;/sub&gt;S&lt;sub&gt;3&lt;/sub&gt;), present in all mines. Surface soils and mine wastes were sampled, together with sediments when ponds or galleries were present. The total Sb concentrations of 18 samples varied from 28 to 221&amp;#160;000&amp;#160;mg kg&lt;sup&gt;-1&lt;/sup&gt;. However, stibnite was only detected in a soil sample from Balanzona mine and tetrahedrite ((Cu,Fe)&lt;sub&gt;12&lt;/sub&gt;Sb&lt;sub&gt;4&lt;/sub&gt;S&lt;sub&gt;13&lt;/sub&gt;)&lt;sub&gt;&lt;/sub&gt;in a sediment from the Balanzona mine. The most common Sb secondary minerals were bindheimite (Pb&lt;sub&gt;2&lt;/sub&gt;Sb&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;6&lt;/sub&gt;O), senarmontite (Sb&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;), valentinite (Sb&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;) and stenhuggarite (CaFeSb(AsO&lt;sub&gt;3&lt;/sub&gt;)&lt;sub&gt;2&lt;/sub&gt;O). These materials were incubated in slurries at 10 % solids, at 25&amp;#176;C under agitation, either in presence of air or under N&lt;sub&gt;2&lt;/sub&gt;/H&lt;sub&gt;2&lt;/sub&gt; atmosphere. Sb was generally more mobile in oxidizing conditions; however, for 2 samples, mobility was higher in reducing conditions. The highest Sb concentrations in water were in the range 20 to 30 mg L&lt;sup&gt;-1&lt;/sup&gt;. The final percentage of solubilized Sb exceeded 1 % (between 1 and 12 %) for 10 samples. For one sediment sampled in Balanzola mine, final Sb concentrations were close to 20 mg L&lt;sup&gt;-1&lt;/sup&gt; in oxidizing conditions and 10 mg L&lt;sup&gt;-1&lt;/sup&gt; in reducing conditions. Acidification was observed with several samples; however, Sb release was not systematically related with the evolution of pH. The mobility of Sb during leaching might be driven by diverse mechanisms: release of sorbed Sb, abiotic or biotic dissolution of Sb-bearing minerals, including oxidation of Sb sulfides in aerobic conditions, or reductive dissolution of Sb-bearing iron or manganese oxides, and finally release of soluble thio-Sb complexes in anaerobic conditions. Supporting the occurrence of these last mechanisms, final analyses indicated solubilization of Fe and Mn and traces of dissolved sulfide in reducing conditions. Our results, that showed a higher mobility of Sb in oxidizing conditions, are globally consistent with previous works indicating a higher occurrence of the oxidized form of Sb, i.e. Sb&lt;sup&gt;V&lt;/sup&gt;, in water streams impacted by mining sites. However, we also observed that non negligible release of Sb can be linked to mechanisms occurring in reducing conditions. Perspectives of this work include the elucidation of the biological processes, directly or indirectly involved in Sb release or immobilisation, in order to better predict the evolution of environmental quality on mining sites and propose remediation strategies.&lt;/p&gt;&lt;p&gt;This work was funded by the ANR (ANR-19-MIN2-0002-01), the AEI (MICIU/AEI/REF.: PCI2019-103779) and author&amp;#8217;s institutions in the framework of the ERA-MIN2 AUREOLE project.&lt;/p&gt;

Repetition is Important to Students and Their Understanding During Laboratory Courses that Include Research

Course-based undergraduate research experiences (CUREs) provide students with opportunities for the same gains that apprenticed research with faculty members offer. As their popularity increases, it is important that critical elements of CUREs are supported by thoughtful design. Student experiences in CUREs can provide important insights into why CUREs are so effective. We present evidence from students who participated in CUREs at the introductory, intermediate, and advanced levels, as well as from graduate teaching assistants for an introductory lab course that included a CURE. Students and teaching assistants describe repetition as a valuable element in CUREs and other laboratory experiences. We used student work and open-ended interviews to identify which of five previously described elements of CUREs students found important. Because repetition was particularly salient, we characterized how students described repetition as they experienced it in courses that contained full-length or &ldquo;micro&rdquo;-CUREs. In prompted interviews, students described how repetition in CUREs provided cognitive (learning concepts) and practical (learning technical skills) value. Recent graduates who had participated in CUREs at each level of their Biology education were particularly aware that they placed value in repetition and acknowledged it as motivational in their own learning. Many students described repetition in metacognitive terms, which also suggests that as students advance through laboratory and CURE curricula, their understanding of how repetition supports their learning becomes more sophisticated. Finally, we integrated student descriptions to suggest ways in which repetition can be designed into CUREs or other laboratory courses to support scientific learning and enhance students&rsquo; sense of scientific identity.

Analyzing the communication in social media of the main sustainable brands during COVID-19 crisis: the Spanish vs. Italian cases

Communication is now a valuable element to demonstrate the degree of commitment and transparency that organizations have towards Sustainability. In a critical moment such that experienced with the COVID-19 crisis, companies recognized facing the challenge of continuous and committed communication on social networks as a sustainable activity. All the latter raises the question whether the brands recognized as the most sustainable have actually succeed on being aware of communicating at the most critical moments of the COVID-19 crisis. In this context, an analysis is made of the activity maintained by the main sustainable companies, both Spanish and Italian, within two of the most popular social networks, Twitter and Instagram, at the very early stages of the crisis in both countries. Our results show that most companies have managed to rise to the occasion and show their commitment to the population through social networks.

Distributions of LRS in varying environments

Studies of lifetime reproductive success (LRS) have shown that important random events can be in ecology and evolution. Randomness should be amplified in stochastic environments, and here we show here we show this to be the case by computing the complete distribution of LRS when vital rates are Markovian can be readily computed by building on our recent paper (Tuljapurkar et al. 2020). These results complement the work of van Daalen and Caswell (2020) on moments of LRS. We use empirical studies of Roe deer, Capreolus capreolus, to show that environments at birth have strong effects on future performance, and that analyses of the LRS in stochastic environments are a valuable element of studies of the consequences of climate change.

Complex processing of tin-lead dross into solders and ligatures

The use of industrial waste is one of the main problems of the modern economy. In Belarus, there is no primary metallurgical processing of natural raw materials, so the use of secondary materials and production waste is a very relevant and important task for the industry, given into account that the cost of metals extracted from secondary raw materials is several times less than the primary ones.One of the types of such raw materials is tin-lead dross (ash), which consists of tin and lead oxides with inclusions of the metal component beads. The most valuable element in dross is tin, the price of which is much higher than the cost of many non-ferrous metals. The aim of the work was to study the influence of various technological factors on the metallurgical output during the processing of tin-lead ash into solders and ligatures.In this regard the results of previous studies related to the extraction of tin and lead in the processing of secondary raw materials were summarized, and new data on technological methods for deeper metallurgical processing of dross (ash) were presented. This allowed them to develop options for obtaining high-quality solder type POS 61 and ligatures.