Extraction of Zinc and Manganese from Alkaline and Zinc-Carbon Spent Batteries by Citric-Sulphuric Acid Solution

The paper is focused on the recovery of zinc and manganese from alkaline and zinc-carbon spent batteries. Metals are extracted by sulphuric acid leaching in the presence of citric acid as reducing agent. Leaching tests are carried out according to a24full factorial design, and empirical equations for Mn and Zn extraction yields are determined from experimental data as a function of pulp density, sulphuric acid concentration, temperature, and citric acid concentration. The highest values experimentally observed for extraction yields were 97% of manganese and 100% of zinc, under the following operating conditions: temperature40∘C, pulp density 20%, sulphuric acid concentration 1.8 M, and citric acid 40 gL-1. A second series of leaching tests is also performed to derive other empirical models to predict zinc and manganese extraction. Precipitation tests, aimed both at investigating precipitation of zinc during leaching and at evaluating recovery options of zinc and manganese, show that a quantitative precipitation of zinc can be reached but a coprecipitation of nearly 30% of manganese also takes place. The achieved results allow to propose a battery recycling process based on a countercurrent reducing leaching by citric acid in sulphuric solution

Biodegradation of two new biomaterials

Introduction. As in the previous experiments the haemostatic swab Antema revealed the disadvantage of troublesome adhesion both to surgical instruments and to serous surfaces of internal organs, the addition of Matemo could speed up the haemostatic performances of both biomaterials reducing the adhesion. For that reason Antema pads were treated with Matemo obtaining new haemostatic swabs. A comparison between the Matemo and the Antema + Matemo pads was then performed to test the haemostatic power and the biodegradation of both biomaterials. Materials and methods. For the experimental protocol the dorsal skin of each anesthetized animal was shaved, incised and two pouches were performed inside the subcutaneous tissue of the back, to introduce a specimen (1 cm2 of size) of Matemo on the left side, and Matemo+Antema on the right side. The same operation was repeated in 3 animals, and 3 other rats were used as controls and treated only with the selected anesthetic without intervention. The treated animals were all killed after 90 days from the operation. All the animals were daily controlled and no accident happens during the post-operation time. After death the dorsal skin of each animal was inspected in the two sides of implant and the samples from the skin and the subcutaneous tissues were taken in both sides of the back, to submit to the histological studies. Results. The microscopic analysis of the histological sections showed that at the deadline of the experiment both biomaterials disappeared from the site of implant, but the two regions were very different. In the left side (Matemo) the subcutaneous tissue appeared quite normal and very poorly infiltrated by the inflammatory cells, without proliferation of new fibrous tissue, neither dermal adhesion to the musculature. In the right side (Antema + Matemo) indeed, a significant infiltration of inflammatory cells was jet detectable and many dense neo-proliferate connective tissue attached the dermal plane to the muscular layer. Then, this protocol confirmed the very interesting results obtained in these studies in which the new synthesized haemostatic biomaterial Matemo was compared with Tabotamp and Antema, both currently used surgical sponges. Also in this experiment Matemo revealed a significant decrease in bleeding time with an absorption rate of the blood very quick and fast and its biodegradation at the 90th day were almost perfect

Increasing biases can be more efficient than increasing weights

We introduce a novel computational unit for neural networks that features multiple biases, challenging the traditional perceptron structure. This unit emphasizes the importance of preserving uncorrupted information as it is passed from one unit to the next, applying activation functions later in the process with specialized biases for each unit. Through both empirical and theoretical analyses, we show that by focusing on increasing biases rather than weights, there is potential for significant enhancement in a neural network model's performance. This approach offers an alternative perspective on optimizing information flow within neural networks. See source code at https://github.com/CuriosAI/dac-dev.Comment: Major rewriting. Supersedes v1 and v2. Focusing on the fact that not all parameters are born equal: biases can be more important than weights. Accordingly, new title and new abstract, and many more experiments on fully connected architectures. This is the extended version of the paper published at WACV 202

In vivo biodegradation of new haemostatic biomaterials

Introduction. The new synthesized haemostatic biomaterial Matemo, is a protein meal produced by fractionation of human plasma. In previous studies it revealed its excellent haemostatic properties, so that it could become the best biomaterial to prefer in large surgical demolition. It also showed an excellent biocompatibility for its composition of human proteins, very similar to that of human tissues. This work now intended to study the in vivo biodegradation of this new biomaterial compared with another horse collagen-based haemostatic biomaterial (Antema) in order to find the best material to fill the empty cavities resulting after surgical resection of tumor masses. Materials and methods. For the experimental protocol the dorsal skin of each anesthetized animal was shaved, incised and two pouches were performed inside the subcutaneous tissue of the back, to introduce a specimen (1 cm2 of size) of Matemo on the left side, and on the right side the horse-collagen biomaterials (Antema). The same operation was repeated in 3 animals, and 3 other rats were used as controls and treated only with the selected anesthetic cocktail without intervention. The treated animals were killed all after 90 days from the operation. After death the dorsal skin of each animal was inspected in the two sides of implant and the samples from the skin and the subcutaneous tissues were taken in both sides of the back, to submit to the histological studies. Results The histological exams carried out in this experiment showed that at the 90th day post-implant both biomaterials were completely reabsorbed, but the sites of implantation were very different between them. In the side of the implanted Matemo the subcutaneous tissue showed a very poor infiltration of inflammatory cells, with a foreign body reaction fully resolved without proliferation of new fibrous tissue, neither dermal adhesion to the muscular plane. In the site of Antema implant, indeed, at the same dead line a significant infiltration of inflammatory cells jet persisted and much dense fibrous tissue attached the dermal plane to the underlying muscles

LA PROGRAMMAZIONE DELLA SPERIMENTAZIONE NELLO SVILUPPO DEI PROCESSI CHIMICI

In the present paper the main advantages obtained in the planning of experimental tests by using factorial design are shown. In particular the general criteria to perform a full and fractional factorial experiments are highlighted. A biotechnological application, regarding an optimisation study of a cultural media in the bioleaching of a manganiferous mineral of industrial interest, is shown as an example

Interazione di Pirazolilborati 3,4,5-TriMe Sostituiti Con Organostagno(IV)

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