Functionalized multi-walled carbon nanotubes for oil spill cleanup from water

The growing global economy resulted in an incessant increase in transportation and exploitation of oil. Hence, the oil spillage has been considered a serious threat to aquatic and terrestrial ecosystems. Therefore, water purification has been considered a major challenge around the world. There are numerous classical methods available for oil removal from water, but owing to multiple defects and disadvantages, research efforts have focused to find such adsorbents which can improve oil adsorption capability. Traditional adsorbent material typically applied in oil removal includes activated carbon, organoclays, wool, zeolites, etc. These materials suffer from several drawbacks such as low absorption capacity, non-selective absorption, and complicated reusability, whereas nano-adsorbents offer multiple advantages such as having multiple sorption sites, large surface area, short intra-particle diffusion distance, tuneable pore size, and ease of low-temperature modification. Multi-walled carbon nanotubes (MWCNTs) are extensively used adsorbent materials with a strong affinity for the removal of organic pollutants. The functionalization MWCNTs further increase the sorption capacity of adsorbents manifolds to remove organic materials. These nanocomposites are also compatible with green materials and considered environmentally friendly adsorbents. This review paper aims at providing an insight to understand the properties of the MWCNTs and their potential use to adsorb hydrocarbons from water. Moreover, the synthesis methods of those materials, their modification procedures including the functionalization with metal oxide nanoparticles, and applications are also discussed in detail.

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Coal rib response during bench mining: A case study

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United States.Over the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in U.S.underground coal mines.Nine of these 12 fatalities(75%) have occurred in room-andpillar mines.The objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 m.This paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site.     

The role of partnerships in water‐related research in Palestine

This study analyses the good effect of science and engineering inputs from partnerships and applied research in promoting sustainable management of water and environmental resources in Palestine. The capacity building achieved during the past 10 years at the Institute of Environmental and Water Studies (IEWS) is reviewed. Palestine faces major constraints, and these affect everyone and everything. A problem‐solving approach can be beneficial.     

Short-term peak demand forecasting in fast developing utility withinherit dynamic load characteristics. I. Application of classicaltime-series methods. II. Improved modelling of system dynamic loadcharacteristics

Estimates of the peak demand pertaining to a typical fast-growing system with inherit dynamic load characteristics are derived from three classical time-series forecasting methods. These demand estimates are compared with corresponding actual values. It is shown that application of sophisticated technological classical forecasting techniques to the forecasting problem of a typical fast-growing utility with dynamic load characteristics gives peak demand forecasts with varying degree of accuracy over the forecasting periods considered. This is mainly due to the inherent inability of these methods to simulate the complex load characteristics arising from the interactions of seasonality, trend, and cyclic moving special events. An attempt is made to isolate the effects of these events and to separately forecast the static and dynamic components of the system demand. The accuracy of the forecasted demand thus obtained is comparatively better than that of the forecast obtained     

3-Hydroxy-3-methylglutaryl-CoA lyase deficiency in a boy with VATER association

BACKGROUND: Objective determination of saphenopopliteal junction incompetency has eluded surgeons for many years. With the advent of duplex ultrasonography incompetency of the saphenopopliteal junction can be determined with an acceptable degree of clinical certitude. OBJECTIVE: This study was undertaken in order to determine the accuracy of duplex ultrasonography in studying the competency of the saphenopopliteal junction. METHODS: A total of 50 patients were included in the study, and the saphenopopliteal junction was studied bilaterally in each patient. The Biosound Phase II Duplex Ultrasound System with a 7.5-mHz B-mode imaging was used. RESULTS: The degree of accuracy of ascertaining the competency of the saphenopopliteal junction was approximately 96%. CONCLUSION: This test is reliable, and provides helpful information to the clinician.     

Pairing of Schistosoma mansoni males in infected Syrian hamsters

Pairing of male schistosomes in the liver of infected hamsters was recorded with Egyptians S. mansoni strain. The homospecific male pairs never carried each other in the gynaecophoric duct, but they being closed in either central or hepatic veins. Other perfused males and females en copula showed normal mating behaviour. The paired males were more or less in the same size. The random sexed miracidia used resulted in obtaining 1:2.1 female/male ratio. It is concluded that the random increase of male schistosomes may create the male pairing behaviour. Also, the migration of female against the blood stream to the mesenteric plexus of the host and the failure of male to catch them may lead to this homosexual pairing. The black haemozoin-like substance seen in mature females was also observed in the pairing males and this probably reflects the effect of scarcity or migration of females to the mesenteric plexus.     

Steady state errors transferred to the turned workpiece

Even if tool and workpiece are set correctly, several errors transfer to the turned workpiece owing to the inherent sources of inaccuracy of the processing system. An evaluation of such errors showed that they partially transfer to the turned workpiece. The ratio of transferred to introduced errors depends upon the ratio of the tangential to the radial compliance of the system.     

Effect of piezoelectric grain size on magnetoelectric coefficient of Pb(Zr0.52Ti0.48)O3–Ni0.8Zn0.2Fe2O4 particulate composites

This study investigates the variation of magnetoelectric (ME) coefficient as a function of the piezoelectric grain size in the composite system of 0.8 Pb(Zr_0.52Ti_0.48)O₃–0.2 Ni_0.8Zn_0.2Fe₂O₄. It was found that as the piezoelectric-phase grain size increases the overall resistivity, piezoelectric, dielectric, and ferroelectric property of the composite increases and saturates above 600 nm. Below 200 nm average grain size, piezoelectric and dielectric properties decrease rapidly. The ferroelectric Curie temperature was found to decrease from 377 to 356 °C as the average grain size decreases from 830 to 111 nm. ME coefficient of the composite showed a rapid change below grain size of 200 nm and was found to saturate above 600 nm to a value of 155 mV/cm.Oe.     

Augmented ε-constraint method in multi-objective flowshop problem with past sequence set-up times and a modified learning effect

This article addresses a general tri-objective non-permutation flowshop problem to minimise the makespan, the sum of flow time and maximum tardiness simultaneously. In order to enhance the applicability of the model, some practical assumptions are included. These are release dates, past sequence-dependent set-up times, a truncated generalisation of Dejong’s learning effect and predetermined machine availability constraints. First, the problem is formulated as a mixed-integer linear programming model. Second, the true Pareto front is achieved with augmented ε-constraint method for small-sized problems. Third, due to the high complexity of the model and the impractical computational times of larger instances, a heuristic algorithm based on the ε-constraint method is also proposed. Finally, the algorithms are tested to gauge their effectiveness, and the results are compared with other methods.     

Scratch and wear resistance of nano-silica-modified silicate conversion coating on aluminium

The silicate conversion coating was modified with nano-silica and applied on the surface of AA2024 by dip-coating technique. The mechanical properties of produced modified silicate layer were investigated by the pencil scratch hardness, cross-cut and abrasion resistance tests. The characterisation of coated surface before and after the tests was studied with optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy and atomic force microscopy. Addition of nano-silica to the silicate coating caused an enhancement in the SiO₂:K₂O ratio. The results showed that the homogeneity of coating surfaces increased in the presence of nano-silica. The wear and scratch resistance of the modified silicate layer improved against the sliding conditions. In addition, the adhesion of coating layer to the substrate metal increased.