A review of the applications of the JK size-dependent breakage model Part 1: ore and coal breakage characterisation

It has been 10 years since the JK size-dependent breakage model was developed (Shi and Kojovic, 2007). This paper reviews 20 applications of the model for the mineral and coal industries in the past 10 years to encourage its use in future applications. The review is divided into three parts: Part 1 for ore and coal breakage characterisation, Part 2 for assessment of material strength and energy requirement for size reduction, and Part 3 for modelling comminution equipment. Part 1 of the review covers the model structure, its applications in high energy single impact data reduction, low energy incremental breakage modelling, reduced breakage testing method, a new impact breakage testing method using mixed particles in a wide size range, fine particle breakage characterisation (JKFBC), and a multi-component breakage model for coal grinding. It has been proved through these applications that the JK size-dependent breakage model is a useful tool for ore and coal breakage characterisation

Enhancing infrared emission of mercury telluride (HgTe) quantum dots by plasmonic structures

The coupling of HgTe quantum dots to a gold nanobump plasmonic array can enhance the spontaneous infrared emission by a factor of five and reduce the influence of nonradiative decay channels

The Renaissance of Black Phosphorus

One hundred years after its first successful synthesis in the bulk form in 1914, black phosphorus (black P) was recently rediscovered from the perspective of a two-dimensional (2D) layered material, attracting tremendous interest from condensed matter physicists, chemists, semiconductor device engineers and material scientists. Similar to graphite and transition metal dichalcogenides (TMDs), black P has a layered structure but with a unique puckered single layer geometry. Because the direct electronic band gap of thin film black P can be varied from 0.3 to around 2 eV, depending on its film thickness, and because of its high carrier mobility and anisotropic in-plane properties, black P is promising for novel applications in nanoelectronics and nanophotonics different from graphene and TMDs. Black P as a nanomaterial has already attracted much attention from researchers within the past year. Here, we offer our opinions on this emerging material with the goal of motivating and inspiring fellow researchers in the 2D materials community and the broad readership of PNAS to discuss and contribute to this exciting new field. We also give our perspectives on future 2D and thin film black P research directions, aiming to assist researchers coming from a variety of disciplines who are desirous of working in this exciting research field.Comment: 23 pages, 6 figures, perspective article, appeared online in PNA

Protective effect of huperzine A against isoproterenol-induced myocardial damage in rats via regulation of PI3K/Akt signaling pathway

Purpose: To investigate the cardioprotective effect of huperzine A (Hup A) against isoproterenol (ISO)- induced myocardial infarction (MI) in rats. Methods: Forty healthy male rats were divided into 4 groups. Control rats received only saline. Rats in Hup A group were injected with Hup A (0.5 mg/kg) only; ISO-treated MI rats were injected with ISO, while ISO + Hup A rats were pre-treated with Hup A prior to ISO exposure and again treated with Hup A. Lipid levels, antioxidant status, cardiac markers, as well as the proteins associated with the PI3k/Akt signaling pathway were determined. Results: Pre- and post-treatment with Hup A resulted in marked reductions in cardiac markers, heart weight, lipid peroxidation product (MDA), and lipid levels, along with improved antioxidant enzyme activities (p < 0.01). Rats treated with Hup A displayed normal cardiac fibrillar structure, relative to ISO- treated rats. Furthermore, the protein expression levels of Akt and PI3k (pAkt/Akt and pPI3k/PI3k ratios) were significantly upregulated (p < 0.01) in Hup A treated rats. Conclusion: Pre- and post-treatment of rats with Hup A exerted potent cardioprotective effect against ISO-induced cardiac failure in rats. Thus, Hup A can potentially be developed as adjuvant therapy in clinical practice for alleviating MI-related problems

Plasmons and screening in monolayer and multilayer black phosphorus

Black phosphorus exhibits a high degree of band anisotropy. However, we found that its in-plane static screening remains relatively isotropic for momenta relevant to elastic long-range scattering processes. On the other hand, the collective electronic excitations in the system exhibit a strong anisotropy. Band non-parabolicity leads to a plasmon frequency which scales as $n^{\beta}$, where $n$ is the carrier concentration, and $\beta<\tfrac{1}{2}$. Screening and charge distribution in the out-of-plane direction are also studied using a non-linear Thomas-Fermi model

A review of the applications of the JK size-dependent breakage model Part 3: comminution equipment modelling.

It has been 10 years since the JK size-dependent breakage model was developed (Shi and Kojovic, 2007). This series of papers present 20 applications of the model for the mineral and coal industries. Part 3 of this series reviews its application to modelling comminution equipment. It is demonstrated that the JK size-dependent breakage model not only can be used for modelling particle breakage, but also can be employed as a basic structure for modelling comminution equipment. This is different to the traditional equipment modelling approaches, in which the population balance models are dominant. In this energy-size reduction modelling approach, the JK size-dependent breakage model provides a key mathematical template to rationally link the size reduction as the equipment model output with ore breakage property and specific energy as the two model inputs. Five case studies are reviewed, which includes modelling of a hammer mill for coke feed preparation, a vertical spindle mill for coal pulverised fuel grinding, a ball mill for batch grinding and continuous operation, HPGR simulations based on piston press testing data, and high voltage pulse disintegration of ores. A common feature of these models is that they all incorporate the measured material breakage characteristic parameters and machine operational conditions that are represented by the size-specific energy relation. The energy-size reduction modelling approach permits the simulations of the effects of changes in ore/coal and machine operating conditions on comminution product size distribution