Studies on corrosion control of naphtha fractions in overhead condensing system using laboratory distillation device

Corrosion in the overhead condensing system of atmospheric distillation units is a common occurrence in petroleum refineries worldwide. These corrosion problems are influenced by the presence of three phases: vapours, liquid hydrocarbons and aqueous phase containing hydrochloric acid formed during distillation by decomposition of chloride salts of calcium and magnesium.Present studies highlight the corrosion control of naphtha fractions of Bombay High and Dubai crude oils in laboratory distillation device by chemical treatment using various corrosion inhibitors having different functional groups. These studies were carried out using two phase systems (aqueous-hydrocarbon) in the distillation device having facilities for monitoring the corrosion and temperatures in vapour condensing region and liquid condensate. Corrosion monitoring was carried out by potentiodynamic polarization technique and dissolved iron analysis using inductively coupled plasma atomic emission spectroscopy (ICPAES). Experimental findings indicate that Dubai naphtha fraction is more corrosive in nature when compared to Bombay High naphtha. This observation can also be explained on the basis of characterization of both crude oils and their naphtha fractions. At normally recommended dosage level as in refinery overhead systems, water soluble corrosion inhibitors are more effective than hydrocarbon soluble ones in the vapour condensing region as well as in the liquid condensate of both naphtha fractions.     

Near room temperature magnetic entropy changes in as-cast Gd100−xMnx (x = 0, 5, 10, 15, and 20 at.%) alloys

A series of Gd_100−xMn_x (x = 0, 5, 10, 15, and 20 at.%) alloys were prepared by arc-melting. The Curie temperature (T_C) associated with the ferromagnetic-paramagnetic transitions, derived from M-T curves, show decrease in T_C for as-cast alloys (∼279 K) as compared to as-cast Gd (∼292 K). No appreciable decrease in the |ΔS_M|_max values ∼4.6 J/kg K (0-2 T) and ∼8.6 J/kg K (0-5 T) were observed upon alloying Gd with Mn up to x ≤ 15 at.%. Refrigerant capacity (q) showed negligible variation ∼195 J/kg (0-2 T) and ∼450 J/kg (0-5 T) with increasing Mn (up to x ≤ 15 at.%) content. Similar values of |ΔS_M|_max and q coupled with ∼13 K decrease in T_C for as-cast Gd_100−xMn_x (0 ≤ x ≤ 15) alloys as compared to Gd, suggests expansion of working temperature region of Gd upon alloying with Mn up to 15 at.%. Low cost, adjustable T_C, favorable magnetocaloric properties make Gd_100−xMn_x alloys potential candidates as second-order transition based magnetic refrigerants for near room temperature air-conditioning and magnetic refrigeration.     

High levels of spontaneous and parasite antigen-driven interleukin-10 production are associated with antigen-specific hyporesponsiveness in human lymphatic filariasis

To determine whether counterregulation by interleukin (IL)-10 plays a role in the generation or maintenance of the antigen-specific hyporesponsiveness seen in asymptomatic microfilaremic (MF) patients, parasite antigen (PAg)- and nonparasite antigen (NPAg)-driven IL-10 production by peripheral blood mononuclear cells (PBMC) was studied in 10 MF patients and in ll patients with chronic lymphatic pathology (CP). PBMC from MF patients spontaneously secreted 10-fold more IL-10 than did PBMC from patients with CP. PAg also induced significantly more IL-10 production by PBMC from CP patients. There was a negative correlation between PAg driven IL-10 production by PBMC and PAg-specific T cell proliferation in the MF group. IL-10 secretion by plastic adherent cells from MF persons was higher in response to PAg than NPAg, whereas IL-6 and tumor necrosis factor-alpha secretion were equivalent for PAg and NPAg, suggesting that PAg preferentially induces IL-10 secretion in these cells. Thus, PAg-induced IL-10 likely plays an important role in down-regulating antigen-specific proliferative responses in MF patients.     

EQL: the language and its implementation

EqL, a general-purpose language that combines the capabilities of functional and logic programming languages, is described. A program in EqL consists of a collection of conditional, pattern-directed rules, where the conditions are expressed as a conjunction of equations, and the patterns are terms built up of data-constructors and basic values. The computational paradigm in EqL is equation solving. Examples illustrating the major features of the language, nondeterminism, deferred evaluation of primitives, and logical variables are presented. The aspects of a sequential implementation for EqL, such as compile-time flattening of equations, run-time equation-delaying, and last-equation optimization, are also described     

A framework for identifying differences and similarities in the managerial competencies associated with different modes of product life extension

It has been noted in the past that economically sound, environmentally preferable life extension modes such as remanufacturing and recycling have special characteristics that complicate the management of their production, logistics and associated operations. This paper considers these complicating characteristics from the perspective of the nine different modes of product life extension. In doing so, a framework and guide is provided to what issues, resource requirements and management capabilities are required for specific life extension modes. This framework provides guidance to practitioners and academics on commonalities between different product life extension modes, thereby assisting practitioners in leveraging current internal skills and capabilities and researchers in determining the generalizability of research.     

Studies on long-term storage stability of biodiesel (B100) and its blend (B20) using Box-Behnken response surface method

The gradual depletion of fossil fuels has greatly enhanced the necessity to look for alternative fuels for automobile engines. In response to this, biodiesel is being considered as a promising and potential alternative substitute to conventional petroleum diesel. However, long-term storage stability of biodiesel is poorer compared to conventional petroleum diesel. The aim of the project work is to study the long-term storage stability of biodiesel (B100) and its blend (B20) prepared from used frying oil in different conditions of storage. In this work, the effect of antioxidants and temperature on long storage stability of biodiesel obtained from with respect to storage period is analysed using response surface methodology (RSM). The long storage of biodiesel obtained from used frying oils were optimised by varying parameters such as antioxidant concentration, storage period by Box-Behnken RSM. The properties such as the acid value and the viscosity of biodiesel were initially measured. The results of the investigation showed that the addition of sufficient concentration of antioxidant (pyrogallol) significantly maintains the acid value and viscosity of biodiesel and helps to store for a longer storage period at the given storage temperature.     

Hierarchical 3D Cobalt‐Doped Fe3O4 Nanospheres@NG Hybrid as an Advanced Anode Material for High‐Performance Asymmetric Supercapacitors

Hierarchical nanostructure, high electrical conductivity, extraordinary specific surface area, and unique porous architecture are essential properties in energy storage and conversion studies. A new type of hierarchical 3D cobalt encapsulated Fe₃O₄ nanosphere is successfully developed on N‐graphene sheet (Co?Fe₃O₄ NS@NG) hybrid with unique nanostructure by simple, scalable, and efficient solvothermal technique. When applied as an electrode material for supercapacitors, hierarchical Co?Fe₃O₄ NS@NG hybrid shows an ultrahigh specific capacitance (775 F g^?1 at a current density of 1 A g^?1) with exceptional rate capability (475 F g^?1 at current density of 50 A g^?1), and admirable cycling performance (97.1% capacitance retention after 10 000 cycles). Furthermore, the fabricated Co?Fe₃O₄ NS@NG//CoMnO₃@NG asymmetric supercapacitor (ASC) device exhibits a high energy density of 89.1 Wh kg^?1 at power density of 0.901 kW kg^?1, and outstanding cycling performance (89.3% capacitance retention after 10 000 cycles). Such eminent electrochemical properties of the Co?Fe₃O₄ NS@NG are due to the high electrical conductivity, ultrahigh surface area, and unique porous architecture. This research first proposes hierarchical Co?Fe₃O₄ NS@NG hybrid as an ultrafast charge?discharge anode material for the ASC device, that holds great potential for the development of high‐performance energy storage devices.     

Dynamic optimal experimental design yields marginal improvement over steady‐state results for computational maximisation of regulatory T‐cell induction in ex vivo culture

The isolation of T cells, followed by differentiation into Regulatory T cells (Tregs), and re‐transplantation into the body has been proposed as a therapeutic option for inflammatory bowel disease. A key requirement for making this a viable therapeutic option is the generation of a large population of Tregs. However, cytokines in the local microenvironment can impact the yield of Tregs during differentiation. As such, experimental design is an essential part of evaluating the importance of different cytokine concentrations for Treg differentiation. However, currently only single, constant concentrations of the cytokines have been investigated. This work addresses this point by performing experimental design in silico which seeks to maximize the predicted induction of Tregs relative to Th17 cells, by selecting an optimal input function for the concentrations of TGF‐β, IL‐2, IL‐6, and IL‐23. While this approach sounds promising, the results show that only marginal improvements in the concentration of Tregs can be achieved for dynamic cytokine profiles as compared to optimal constant concentrations. Since constant concentrations are easier to implement in experiments, it is recommended for this particular system to keep the concentrations constant where IL‐6 should be kept low and high concentrations of TGF‐β, IL‐2, and IL‐23 should be used.Inspec keywords: patient treatment, molecular biophysics, proteins, cellular biophysics, diseasesOther keywords: Tregs relative, optimal input function, dynamic cytokine profiles, optimal constant concentrations, IL‐23, computational maximisation, regulatory T‐cell induction, inflammatory bowel disease, viable therapeutic option, local microenvironment, Treg differentiation, single concentrations, predicted induction, dynamic optimal experimental design, interleukin‐2, IL‐6, transforming growth factor‐β     

Harakeke (phormium tenax) fibre–waste plastics blend composites processed by screwless extrusion

Most plastic packaging products are discarded after a single use resulting in an abundant supply of waste plastics. Natural fibres are light in weight, abundant and inexpensive. The stiffness and strength of polymers have been shown to improve with the incorporation of natural fibres. Hence, composite materials made of natural fibres and waste plastics would result in the reduction of plastic wastes and the use of fibres from renewable resources. Composite specimens and sheets consisting of fibres from the New Zealand flax plant, phormium tenax or Harakeke as it is known in Maori, and waste plastics have been produced through screwless extrusion followed by injection moulding. The tensile and impact properties of these composites have been determined. The formability of these composites has been assessed through thermoforming.