From binary to multinary copper based nitrides - unlocking the potential of new applications

This review summarizes the current knowledge on the chemistry of binary copper(I) nitride, Cu3N and its multinary derivatives containing either main group or transition metal elements. For many years, research in this area was focused on the development of copper nitride prepared in the form of thin films. Successful deposition of these materials has been achieved mainly by employing physical methods, which have provided materials suitable for potential application in optical data storage. However, for the last decade, attention has also been devoted to expanding the available options by which Cu3N can be synthesized and deposited. Consequently, the focus has switched to the development of chemical synthetic methods towards the fabrication of this semiconductor and to broadening the range of related compounds that might be discovered. Simultaneously, the formulation of novel techniques and the successful preparation of new nanostructured functional materials has resulted in the rapid evolution of new and relevant applications; e.g. catalytic and electrochemical. The overview presented here concentrates on the chemical methods that have been devised to synthesise both bulk samples and thin films of Cu3N. Our article also shows how these approaches have been developed to achieve significant progress in the creation of multinary copper based nitrides and in identifying their potential applications. It provides a concise history of previous copper nitride research and sets the context for the most current advances. These will no doubt provide the springboard for future research areas that will impact both transition metal nitride chemistry and materials science more generally

Effect of Long-Term Zinc Pollution on Soil Microbial Community Resistance to Repeated Contamination

The aim of the study was to compare the effects of stress (contamination trials) on the microorganisms in zinc-polluted soil (5,018 mg Zn kg−1 soil dry weight) and unpolluted soil (141 mg Zn kg−1 soil dw), measured as soil respiration rate. In the laboratory, soils were subjected to copper contamination (0, 500, 1,500 and 4,500 mg kg−1 soil dw), and then a bactericide (oxytetracycline) combined with a fungicide (captan) along with glucose (10 mg g−1 soil dw each) were added. There was a highly significant effect of soil type, copper treatment and oxytetracycline/captan treatment. The initial respiration rate of chronically zinc-polluted soil was higher than that of unpolluted soil, but in the copper treatment it showed a greater decline. Microorganisms in copper-treated soil were more susceptible to oxytetracycline/captan contamination. After the successive soil contamination trials the decline of soil respiration was greater in zinc-polluted soil than in unpolluted soil

Polymer nanofilms with enhanced microporosity by interfacial polymerization

Highly permeable and selective membranes are desirable for energy-efficient gas and liquid separations. Microporous organic polymers have attracted significant attention in this respect owing to their high porosity, permeability, and molecular selectivity. However, it remains challenging to fabricate selective polymer membranes with controlled microporosity which are stable in solvents. Here we report a new approach to designing crosslinked, rigid polymer nanofilms with enhanced microporosity by manipulating the molecular structure. Ultra-thin polyarylate nanofilms with thickness down to 20 nm were formed in-situ by interfacial polymerisation. Enhanced microporosity and higher interconnectivity of intermolecular network voids, as rationalised by molecular simulations, are achieved by utilising contorted monomers for the interfacial polymerisation. Composite membranes comprising polyarylate nanofilms with enhanced microporosity fabricated in-situ on crosslinked polyimide ultrafiltration membranes show outstanding separation performance in organic solvents, with up to two orders of magnitude higher solvent permeance than membranes fabricated with nanofilms made from noncontorted planar monomers

Additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics

Purpose: The paper is a comprehensive review of the literature on additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics. Design/methodology/approach: Extensive literature studies on conventional powder engineering technologies have been carried out. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: The additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics as the advanced digital production (ADP) technologies are located in the two-quarters of the dendrological matrix of technologies "wide-stretching oak" and "rooted dwarf mountain pine" respectively. It proves their highest possible potential and attractiveness, as well as their fully exploited attractiveness or substantial development opportunities in this respect. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics are becoming very important among product manufacturing technologies. They are an essential part not only of powder engineering but also of the manufacturing development according to the concept of Industry 4.0

Overview of conventional technologies using the powders of metals, their alloys and ceramics in Industry 4.0 stage

Purpose: Among the technologies that play a crucial role in the current stage of development of Industry 4.0 conventional powder engineering technologies are of great importance. Based on a comprehensive literature review, conventional technologies using the powders of metals, their alloys and ceramics are described. Development perspectives of the most widespread among them were indicated. Design/methodology/approach: Extensive literature studies on conventional powder engineering technologies have been carried out. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: In addition to the presentation of conventional sintering technological methods, sintering mechanisms in solid-state and liquid phase sintering which accounts for 90% of the commercial value of sintered products are presented. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them conventional powder engineering technologies play a key role in current industry development. For this reason, these technologies have been characterized in detail on the basis of available literature sources

The digitisation for the immediate dental implantation of incisors with immediate individual prosthetic restoration

Purpose: The purpose of this study is to present the author's method of planning the procedure of immediate implant-prosthetic restoration in place of a tooth qualified for removal by performing a surgical template and implant-prosthetic restoration based on data obtained in the CBCT test and intraoral scanning 3D model. Design/methodology/approach: The method of planning the implant surgery through the design and manufacture of surgical templates and implant prostheses performed before the start of medical procedures was described on the basis of actual clinical data from patients with anterior segment teeth qualified for extraction for reasons of complications after endodontic treatment. The placement of the implant was planned using virtual reality, where the bone model and the virtual soft tissue model were combined, which made it possible to perform a surgical template and prosthetic implant restoration. For the manufacturing, 3D printing as stereolithography SLA and selective laser sintering SLS for the surgical template manufacturing and CNC milling in the case of the prosthetic implant were used for restoration. Findings: The method allows planning the implant position based on two connected bone and soft tissue models and allows to design and manufacture a surgical guide. In this way, it becomes possible to place implants in the patient's bone during surgery procedure in the planned position and to install the prosthetic implant restoration in the form of an individual abutment and a PMMA crown during the same procedure in the surgical part. Practical implications: Thanks to the method of computer-aided design/manufacturing CAD/CAM production of surgical templates and prosthetic restoration based only on digital models and the planned position of the implant, it is possible to carry out the procedure of immediate tooth extraction and replacement with permanent prosthetic restoration. The whole process is based on the CBCT test performed at the beginning. The presented method allows shortening the procedure time by four times and the rehabilitation time by 3-6 months when performing the procedure in a minimally invasive manner. Originality/value: This article presents the original design and production method of surgical guides. It allows for precise planning of the implant position and transfer of this data to the patient's mouth during the procedure, enabling permanent prosthetic restoration before starting medical procedures

Manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics

Purpose: The paper is a comprehensive review of the literature on manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics. Design/methodology/approach: Extensive literature studies on manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics have been carried out. The paper is illustrated with examples of various structure images obtained as part of research of engineering materials made by authors with powders. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: The manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics as the advanced digital production (ADP) technologies are proves the highest possible potential and relatively good attractiveness, as well as their fully exploited attractiveness or substantial development opportunities in this respect. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics are becoming very important among product manufacturing technologies. They are an essential part of powder engineering

Application of polymer impression masses for the obtaining of dental working models for the stereolithographic 3D printing

Purpose: The aim of the work is to execute measurements of digital dental models taken by scanning prosthetic impressions using the engineering CAD software and finding dimensional differences and scale factor for precise reproduction of patient tooth dimensions. Design/methodology/approach: Tests were carried out involving the execution of 3 series of impressions for selected impression materials, which were then scanned using two types of prosthetic scanners. Gypsum models based on mentioned impressions were scanned and dimensionally compared with impression-based digital models. Benchmark impressions were also performed in order to verify the obtained results and determine the correction factor for dimensions. The dimensional differences between impression groups were calculated by using Engineering CAD software. Findings: It was found, that compared to the base model, the digital model has a smaller volume than the object being mapped, the digital models based directly on the impression should be 0.09 - 0.12% rescaled to match the dimensions of the base model. Research limitations/implications: It is necessary to perform a practical verification of the results achieved and apply the determined coefficient in practice by creating working models using precise devices such as a 3D SLA printer and verify their results with intraoral scanner based models. Practical implications: This test will allow making precise working models using a 3D printer, allowing finally to perform, for example, implant-based bridges directly from the level of implants, using the masses described in the study. Originality/value: The comparative studies of polyvinyl siloxane and alignate impression materials were carried out in order to measure dimensional differences between working models made directly from the impression and gypsum models and compared with pattern, which allowed to determine the expansion coefficient, which will allow to work in 3D printing technology with close representation of real situation in the patient's oral cavity, which is particularly important when performing full arch bridges and extensive work on implants, including direct implants. The work has practical applications for both dental engineers and dentists performing advanced prosthetic work

Manufacturing powders of metals, their alloys and ceramics and the importance of conventional and additive technologies for products manufacturing in Industry 4.0 stage

Purpose: The paper is a literature review indicating the importance of powder engineering in the modern stage of Industry 4.0 development. 47 technologies for the manufacturing and use the powders of metal and their alloys and ceramic in the manufacturing of products are indicated. All those technologies were compared in terms of their potential and attractiveness, pointing to their development trends. The focus was solely on powder production methods. Other technologies will be discussed in other papers in the powder engineering cycle. Design/methodology/approach: The authors' considerations are based on an extensive literature study and the results of the authors' previous studies and empirical work. In order to compare the analyzed technologies, the methodology of knowledge engineering are used, including the own method of contextual matrices for comparative analysis of a large set of technologies by presenting them on a dendrological matrix. Findings: The most interesting intellectual achievements contained in the paper include presentations of the authors' original concepts regarding the augmentation of the Industry 4.0 model. Material processing technologies occupy an important place in it, among them powder engineering technologies, both conventional and additive. The most attractive and promising development technologies in powder engineering are identified. Originality/value: The originality of the paper is associated with the novelty of the approach to analysing powder engineering, an indication of its importance for the development of the Industry 4.0 idea, where progress does not depend only on the development of IT technologies. It is also not true that from among technologies only additive technologies play a key role. Using avant-garde analyses in the field of knowledge engineering, the most avant-garde technologies of powder engineering are pointed out