Recent progress on biosorption of heavy metals from liquids using low cost biosorbents : characterization, biosorption parameters and mechanism studies

A significant number of biosorption studies on the removal of heavy metal from aqueous solutions have been conducted worldwide. Nearly all of them have been directed towards optimizing biosorption parameters to obtain the highest removal efficiency while the rest of them are concerned with the biosorption mechanism. Combinations of FTIR, SEM-EDX, TEM as well as classical methods such as titrations are extremely useful in determining the main processes on the surfaces of biosorbents. Diverse functional groups represented by carboxyl, hydroxyl, sulfate and amino groups play significant roles in the biosorption process. Solution pH normally has a large impact on biosorption performance. In brief, ion exchange and complexation can be pointed out as the most prevalent mechanisms for the biosorption of most heavy metals.

Ionic liquid electrolyte for lithium metal batteries : physical, electrochemical, and interfacial studies of N-Methyl-N-butylmorpholinium Bis(fluorosulfonyl)imide

The ionic liquid (IL) N-methyl-N-butylmorpholinium bis(fluorosulfonyl)imide (C₄mmor FSI) is examined from physical and electrochemical perspectives. Pulsed field gradient NMR spectroscopy shows that ion diffusivities are low compared with similar, non-ethereal ILs. Ionicity values indicate that above room temperature, less than 50% of ions contribute to conductivity.

Lithium cycling in symmetrical cells using a C₄mmor FSI-based electrolyte is best demonstrated at elevated temperatures. Specific capacities of 130 mAh g⁻¹ are achieved in a Li−LiFePO₄ battery at 85 °C. FT-IR spectroscopic investigations of lithium electrodes suggest the presence of alkoxide species in the solid electrolyte interphase (SEI), implying a ring-opening reaction of C₄mmor with lithium metal. In contrast, the SEI derived from N-methyl-N-propylpiperidinium FSI lacks the alkoxide signature but shows signs of alkyl unsaturation, and the activation energy for Li+ transport through this SEI is slightly lower than that for the C₄mmor-derived SEI. Our detailed findings give insight into the capabilities and limitations of rechargeable lithium metal batteries utilizing a C₄mmor FSI electrolyte.

Antimicrobial and toxicological studies of some metal complexes of 4-methylpiperazine-1-carbodithioate and phenanthroline mixed ligands

A few mixed ligand transition metal carbodithioate complexes of the general formula [M(4-MPipzcdt)_x(phen)_y]Y (M = Mn(II), Co(II), Zn(II); 4-MPipzcdt = 4-methylpiperazine-1-carbodithioate; phen = 1,10-phenanthroline; x = 1 and y = 2 when Y = Cl; x = 2 and y = 1 when Y = nil) were synthesized and screened for their antimicrobial activity against Candida albicans, Escherichia coli, Pseudomonas aeruginosa,Staphylococcus aureus and Enterococcusfaecalis by disk diffusion method. All the complexes exhibited prominent antimicrobial activity against tested pathogenic strains with the MIC values in the range <8-512 μgmL-1. The complexes [Mn(4-MPipzcdt)₂(phen)] and [Co(4-MPipzcdt)(phen)₂]Cl inhibited the growth of Candida albicans at a concentration as low as 8 µgmL^-1.The complexes were also evaluated for their toxicity towards human transformed rhabdomyosarcoma cells (RD cells). Moderate cell viability of the RD cells was exhibited against the metal complexes.

Structural phase transformations of Mg3N2 at high pressure : experimental and theoretical studies

The structural behavior of Mg₃N₂ has been investigated up to 40.7 GPa at room temperature by means of angle-dispersive X-ray diffraction. A reversible, first-order structural phase transition from the ambient cubic phase (Ia3̅) to a high-pressure monoclinic phase (C2/m) is found to start at ~ 20.6 GPa and complete at ~ 32.5 GPa for the first time. The equation of state determined from our experiments yields bulk moduli of 110.7(2) and 171.5(1) GPa for the cubic and monoclinic phases, respectively, indicating higher incompressibility of the high-pressure phase of Mg₃N₂. First-principles calculations reproduced the phase stability and transition pressure determined in our experiment. In addition, a second phase transition from the monoclinic phase to a hexagonal phase (P3̅m₁) was predicted around 67 GPa for Mg₃N₂. The electronic band structures of three phases of Mg₃N₂ are also calculated and discussed.

Philosophy and the view from above in Alejandro's Amenabar's agora

 This paper examines the depiction of neoplatonic philosopher, geometer and astronomer Hypatia in Alejandro Amenabar's 2010 fil Agora.  The paper uses Pierre Hadot's work, and his arguments that ancient philosophy was conceived as a way of life, aiming at the ideal existence of the sage, and characterised by spiritual exercises.  The paper argues that Amenabar's film employs the technique of the view from above, one such spiritual exercise, wherein the agent relooks at his or life sub spaecie aeternitatis or 'from above', to frame Hypatia's life and death, and the end of the pagan epoch in Alexandria.

Teaching or preaching — Max Charlesworth and religious education

In this essay I elaborate on the theoretical framework – that of Millian liberalism – that Max Charlesworth brought to many public issues, including that of the relation between education and religion. I will then apply this framework to a debate in which I have been recently involved myself: a debate around the provision of religious instruction in public schools. In the first section I expound Charlesworth’s rejection of secularism in education in a liberal pluralist state and his defence of faith-based schooling. In the second section I uncover the religious motivations behind the Victorian government’s 1950 amendments to the apparently secularist Victorian Education Act of 1872. In section three, I explore the notion of secularism more fully and suggest that the struggle between those who espouse religious instruction in state schools and those who oppose it while advocating a more general form of education about religion is a symptom of a deeper tension between liberalism and communitarianism within the culture of modernist, liberal states.

Localized corrosion and inhibition studies using the wire beam electrode in conjunction with the electrochemical noise analysis and the scanning reference electrode techniques

Several new technical developments have been made based on the combined use of the wire beam electrode (WBE), electrochemical noise analysis (ENA) and the scanning reference electrode technique (SRET). These have included: (i) The WBE-R n method- the combined use of the WBE and the noise resistance (Rn) to map the rates and patterns of uniform or localized corrosion; (ii) The WBE-Noise Signatures method- the combined use of the WBE and the noise signature to detect the origination and propagation of localized corrosion; and (iii) The WBE-SRET method- the combined use of the WBE and SRET to investigate localized corrosion from both the metallic and electrolyte phases of a corroding metal surface. This paper presents a brief review on these novel methods and their applications for detecting general and localized corrosion, for mapping the rates of corrosion, and for studying corrosion inhibitors.