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The thermal management of electrical insulations poses a challenge in electrical devices as electrical insulators are also thermal insulators. Diamond is the best solid electrical insulator and thermal conductor. This can lead to a paradigm change for electrical machine winding and lamination insulation design and thermal management. The paper introduces these techniques and discusses its effect for the design of electrical machines and its potential consequences for electromagnetic analysis, for example, in multi-physics modelling. The diamond winding insulation is patent-pending, but the diamond enriched lamination insulation is published for the benefit of the scientific community.

The windings of electrical machines are insulated to avoid contact between the coil and other conductive components, for example, the stator core. The principle of using mica tape and resin impregnation has not changed for a century and is well established to produce main insulation on a complex conductor shape and size. These insulations have poor heat-conducting properties. Similarly, the insulation of laminated steel sheets comprising the stator and rotor restrict heat flow. Diamond-based insulation provides a new path. Increased thermal conductivity means reduced temperature rise and the reduced thermal time constants in multi-physics simulations and system analysis.

The largest benefit of a diamond-based core insulation is in electrical machines in which the losses are conducted axially to the coolant. These are machines with radial ducts and effective cooling in the end regions. The main benefit will be in reducing the number of radial ducts that positively affect the size, production costs and the copper losses of the machine. The increased thermal conductivity of the diamond insulation system will reduce the thermal constants noticeably. These will affect system behavior and the corresponding simulation methods.

Diamond insulation can lead to a paradigm change for electrical machine winding and lamination insulation design and thermal management. It might also lead to new modeling requirements in system analysis.

The purpose of this paper is to discuss the dispersion capacity and tribological behavior of liquid paraffin added by diamond nanoparticles.

The structure of the modified diamond nanoparticles which are prepared by oleic acid (OA) is observed by scanning electron microscopy (SEM) and infrared spectroscopy (IR). The dispersivity of these nanoparticles in liquid paraffin is measured by nanoparticle analyzer. The tribological behavior of adding diamond nanoparticles in liquid paraffin is evaluated by using a ball‐on‐ring wear tester.

The measurement results reveal the dispersion capability of OA modified diamond nanoparticles and indicate the dispersing stability in liquid paraffin of the OA which is bonded to the surface of diamond nanoparticles through esterification. It is found from wear testing results that the diamond nanoparticle as additive in liquid paraffin at proper concentration shows better tribological properties for anti‐wear (AW) and antifriction than the pure paraffin oil and different AW ability depending on the particle size.

It is shown in the paper that by reducing friction and AW, the lubricant prepared by the methods described can prolong operating hours of machinery.

The tradition of celebrating an engagement with the gift of a natural diamond ring is largely an American custom. The custom helps drive 2002 retail sales of all diamonds in the USA ($27.4 billion) to 50 percent of global revenues. As a result, anything affecting the US diamond market, especially with diamond engagement rings, is likely to have worldwide implications for the natural diamond marketplace. Millions of American couples are now cohabitating prior to engagement or marriage, and the diamond industry can be facing some unusual social and economic forces. This article reports on a study a study to determine how a group of younger persons, mainly between the ages of 20 and 30, view the desirability of engagement ring purchasing.

In this paper, we aim to understand why consumers often prefer products made using traditional practices even when products made using new practices are not of lower quality. We argue that this resistance, which we call “production process conservatism,” is heightened when the product is used in the performance of a social ritual.

We develop this argument in the context of diamond jewelry, as consumers have generally been resistant to diamonds that are produced in laboratories, i.e., lab-created diamonds. Hypotheses were tested using experiments conducted with an online sample (Experiment 1) and with an MBA student sample (Experiment 2).

In Experiment 1, we find that married female respondents significantly prefer mined diamonds to lab-created diamonds when they are used as part of an engagement gift as opposed to a more routine gift. In Experiment 2, we find the same effect among women; in addition, the perceived risk associated with the ritual is found to mediate this production process conservatism.

This paper contributes to the understanding of a macrosocial phenomenon – acceptance of an innovation – by examining microinteractive processes in groups.

This paper develops an original theory that when individuals deviate from traditional aspects of rituals, they risk signaling a lack of commitment or cultural competence to the group even when such aspects are not explicitly stated.

Material extrusion technology is considered to be an effective way to realize the accurate and integrated manufacturing of high-performance metal diamond tools with complex structures. The present work aims to report the G4 binder that can be used to create metal composite filament loading high concentrations of large diamond particles through comparative experiments.

The quality of filaments was evaluated by surface topography observation and porosity measurement. And the printability of filaments was further studied by the tensile test, rheological test, shear analysis and printing test.

The results show that the G4 binder exhibits the best capacity for loading diamonds among G1–G4. The L4 filament created with G4 has no defects such as pores, cracks and patterns on the surface and section, and has the lowest porosity, which is about 1/3 of the L1. Therefore, the diamond-containing composite filament based on G4 binder exhibits the best quality. On the other hand, the results of the tensile test of L5–L8 filaments reveal that as the diamond content increases from 10% to 30%, the tensile strength of the filament decreases by 29.52%, and the retention force coefficient decreases by 15.74%. This can be attributed to the formation of inefficient bonding areas of the clustered diamond particles inside the composite filament, which also leads to a weakening of the shear strength. Despite this, the results of the printing test show that the diamond-containing composite filament based on the G4 binder has reliable printability.

Therefore, the G4 binder is considered to solve the most critical first challenge in the development of diamond-containing filament.

This paper aims to investigate the effect and mechanism of O atom single doping, Ce and O atoms co-doping on the interfacial microscopic behavior of brazed Ni-Cr/diamond.

Using first-principles calculations, the embedding energy, work of separation, interfacial energy and electronic structures of Ni-Cr-O/diamond and Ni-Cr-O-Ce/diamond interface models were calculated. Then, the effect of Ce and O co-doping was experimentally verified through brazed diamond with CeO₂-added Ni-Cr filler alloy.

The results show that O single-doping reduces the interfacial bonding strength between Ni-Cr filler alloy and diamond but enhances its interfacial stability to some extent. However, the Ce and O co-doping simultaneously enhances the interfacial bonding strength and stability between Ni-Cr filler alloy and diamond. The in-situ formed Ce-O oxide at interface impedes the direct contact between diamond and Ni-Cr filler alloy, which weakens the catalytic effect of Ni element on diamond graphitization. It is experimentally found that the fine rod-shaped Cr₃C₂ and Cr₇C₃ carbides are generated on diamond surface brazed with CeO₂-added Ni-Cr filler alloy. After grinding, the brazed diamond grits, brazed with CeO₂-added Ni-Cr filler alloy, present few fracture and the percentage of intact diamond reaches 67.8%. Compared to pure Ni-Cr filler alloy, the brazed diamond with CeO₂-added Ni-Cr filler alloy exhibit the better wear resistance and the slighter thermal damage.

Using first-principles calculations, the effect of Ce and O atoms co-doping on the brazed diamond with Ni-Cr filler alloy is investigated, and the calculation results are verified experimentally. Through the first-principles calculations, the interface behavior and reaction mechanism between diamond and filler alloy can be well disclosed, and the composition of filler alloy can be optimized, which will be beneficial for synergistically realizing the enhanced interface bonding and reduced thermal damage of brazed diamond.

The Republic of Sakha (Yakutia) has a rich diversity of mineral resources and produces 99 per cent of Russia’s diamonds, worth annually US$1.5 billion and amounting to between 20‐25 per cent of the world’s output. During the period 1974 to 1987, ten “peaceful” underground nuclear explosions were made in the diamond province. One of these directly supported the diamond mining operations, but it “back‐fired”, contaminating the surface with radionuclides such as caesium‐137, strontium‐90, plutonium‐239 and 240, and americium‐241. Furthermore, the low level of implementation of existing environmental legislation by the diamond mining company has resulted in contamination of the river systems which are the key sources of drinking water, and has significantly affected the health status of the population, which may have long‐lasting consequences, as there is increasing evidence of genetic abnormalities. This paper investigates the exploitation of diamond reserves in the Republic of Sakha and its environmental, social and health impacts, and reviews the actions taken by the Government of the Republic to tackle these problems.

In negotiation with diamond enterprises, Aboriginal communities have provided their consent for the diamond mines and have ensured their participation in all diamond projects within their traditional territories. The purpose of this study is to evaluate partnership strategies.

Interviews.

Natural resource enterprises support more than 650 Canadian communities and according to industry Canada this accounts for 12 percent of Canada's gross domestic product. The diamond industry accounts for 4 percent of the nation's expenditures on mining and processing and it is poised for significant growth and contribution to the economy. This emerging industry has created a unique opportunity for Aboriginal people of the Northwest Territories, also known as NWT.

Diavik's success story shows that a good mining strategy is to think beyond extraction, and to be a good corporate citizen, supporting communities and their enterprises. In 2005, the Canadian Council for Aboriginal Business awarded Diavik the gold award. As well, the Prospectors and Developers Association of Canada awarded Diavik an award for protecting its natural surroundings and for its efforts to establish and maintain good relations with local communities.

Five communities have signed partnership agreements with Diavik Diamond Mines Inc., providing joint control of training, employment and business opportunities. This paper discusses the commitments, and the progress, made by Diavik in the participation agreements.