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THE importance of the pre‐treatment of steel before the application of a rust inhibitive or a rust‐proofing material is often not fully understood; this accounts for many failures, loss of time, money, and materials. The worst aspect of faulty pre‐treatment is probably that it will entail frequent maintenance work, and the eventual replacement of the inadequately protected metal.

Investigates the adhesion and corrosion performance of selected silanes in primed galvanised steel. For comparison HDG steel was also treated with a chromate‐free and a chromate‐containing pre‐treatment. All treated panels were painted with three different primers. Corrosion resistance and paint adhesion of the primed panels were studied. Surface energy of the panels was measured by the contact angle method and is reported in terms of the Lewis base component. The corrosion resistance of the panels depended on the combination of the silane and the primer. Vinyltrimethoxysilane (VS) and γ‐aminopropyltriethoxysilane (γ‐APS) treatments improved the corrosion resistance of polyurethane primed panels. γ‐ureidopropyltrimethoxysilane (γ‐UPS) and VS treatments improved the performance of polyester primed panels. A relationship between the base components and the prohesion test results of γ‐UPS and γ‐APS treated panels was found, which indicates that acid‐base interactions improve the adhesion between these two silanes and the primers. γ‐UPS and γ‐APS treated panels also achieved excellent results in the humidity test with all three polymer coatings.

–Prosopis juliflora is a raw material for long-term sustainable production of bioethanol. The purpose of this paper is to identify the best combination of pre-treatment strategy implemented on the lignocellulosic biomass Prosopis juliflora for bioethanol production.

Pre-treatment of lignocellulosic material was carried out using acid, alkali and sonication in order to characterize the biomass for bioethanol production. Prosopis juliflora stem was subjected to steam at reduce temperature (121°C) for one hour residence time initially. Further acid and alkali treatment was carried out individually followed by combinations of acid and sonication, alkali and sonication. Sodium hydroxide, potassium hydroxide, hydrochloric acid, sulphuric acid and nitric acid were used with 3 per cent (w/v) and 3 per cent (v/v) concentration under temperature range of 60-90°C for 60 min incubation time. Sonication under 60°C for 5 min and 40 KHz frequency was carried out. Pre-treated sample were further characterised using field emission scanning electron microscope and Fourier transform infrared spectroscopy to understand the changes in surface morphology and functional characteristics.

In sono assisted acid treatment-based method, nitric acid yields better cellulose content at 70°C and removes lignin that even at increased temperatures no burning was observed.

The paper adds to the scarce research available on the combination of auto hydrolysis coupled with sono assisted acid/alkali hydrolysis which is yet to be practiced.

The purpose of this paper is to study the impact of unemployment on coronary heart diseases (CHD) in Italy on a sample of male manual workers in the private sector.

The authors investigate the association between CHD and different unemployment experiences (ever unemployed; short, mid and long cumulative unemployment), exploiting a large Italian administrative database on careers and health. The study design is based on the balancing of individuals' characteristics during a 12-year pre-treatment period; the measurement of unemployment occurrence during a seven-year treatment period; the observation of CHD occurrence during a five-year follow up. The workers characteristics and the probability of receiving the treatment are balanced by means of propensity score matching. Standard diagnostics on the balancing assumption are discussed and satisfied, while the robustness to violations of the unconfoundedness assumption is evaluated by a simulation-based sensitivity analysis.

The authors find a significant increase of CHD probability was found among workers who experience more than three years of unemployment (relative risks (RR)=1.91, p<0.1), and among those who exit unemployment starting a self-employment activity (RR=1.70, p<0.1). Using different selections of the study population, a clear pattern emerges: the healthier and more labour market attached are workers during pre-treatment, the greater is the negative impact of long-term unemployment on health (RR=2.79, p<0.01).

The very large representative sample (n=69,937) and the deep longitudinal dimension of the data (1985-2008) allowed the authors to minimize the risks of health selection and unemployment misclassification. Moreover, the adopted definition of unemployment corrected some undercoverage and misclassification issues that affect studies based on a purely administrative definition and that treat unemployment as a unique career event disregarding the duration of the experience.

Supporting many policies of contaminated sites management, the risk assessment methodology needs a deep knowledge of the characteristics of the contamination of soils. Physico‐chemical analysis has to take in account the heterogeneity and the specificity of the soil. A better knowledge of the interactions between the chemical substances and the matrix should be developed and its influence on the measurement chain shall be determined. In particular, the influence on the final result of each of the analytical steps (pre‐treatment, extraction, purification, analysis) has to be quantified. An experimental protocol has been designed to study the influence of the type of pre‐treatment chosen in relation to the characteristics of the matrix of real contaminated soils by PCB and PAH. The results show and quantify how the texture, the granulometry, the water content and the total organic carbon (TOC) content may affect the analytical result depending on the analytical pre‐treatment‐step chosen.

Traditionally evaluators of offending behaviour programmes have examined group-level mean change in treatment targets without acknowledging the potential variability of change at an individual level. Clinically significant change, although used widely in the therapy literature generally, has only recently been examined within forensic therapeutic contexts. This chapter provides an overview of key concepts, and the published literature in which clinically significant change has been examined within forensic samples is reviewed. It is concluded that although this technique has the potential to validate programme theory, it is yet to be used to its full potential within a forensic context.

The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV‐values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems.

In this investigation, two different spectrometric techniques, inductively coupled plasma‐optical emission spectrometers (ICP‐OES) and rotating disk electrode‐optical emission spectrometers (RDE‐OES), have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. The study was based on a series of measurements using artificial contamination mixed with oil.

The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre‐treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave‐assisted acid digestion could be used for sample pre‐treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case. The ICP has a repeatability value of r=3 percent and a reproducibility value of R=12 percent for contamination levels of between 50 and 400 ppm and r=0.6  and R=2 ppm, respectively, at values below 50 ppm. The RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre‐treatment is not used. It is therefore not good at detecting wear mechanisms that produces dense/large particles (if the oil samples are not pre‐treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case. The RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of R=r=25 percent for contamination levels between 20 and 500 ppm and R=r=6 ppm for contamination level below 20 ppm.

Only the effects from lubricating oils are studied.

This study will significantly increase the industrial knowledge concerning measurement precision in particle contamination measurement systems.

No similar study is found.

One way of overcoming logistics barriers (poor transportation, handling and storage properties) towards increased utilisation of biomass is to introduce a pre‐treatment process such as torrefaction early in the biomass‐to‐energy supply chain. Torrefaction offers a range of potentially beneficial logistics properties but the actual benefits depend upon how the supply chain is configured to address various elements of customer demand. Hence, the aim of this paper is to develop a framework for torrefaction configuration in a supply chain perspective for different types of customers.

Sophisticated pre‐treatment processes are yet to reach the commercialisation phase. Identification of possible supply chain configurations is in this paper done through a conceptual approach by bringing together knowledge from related research fields such as unrefined forest fuel, pellets and coal logistics with prescriptions for configuration derived from the subject area of supply chain management (SCM).

A framework that explicates different elements of supply and demand of torrefaction is proposed, and exemplified by three distinct supply chains. Depending on demand, torrefaction serves different purposes, bridging gaps in place, time, quality and ownership. Furthermore, different supply chain configurations will pose different requirements on torrefaction in terms of producing different product quality, durability, energy density and hydrophobicity of the pellets.

The proposed framework entails a set of propositions, but requires further development through empirical studies using complementary research methods such as interviews or surveys and quantification through techno‐economical or optimisation from a supply chain perspective.

This paper provides a framework that can inform decisions makers in biomass‐to‐energy supply chains, in particular at torrefaction plants, on upstream and downstream implications of their decisions.

The findings have implications for biomass‐to‐energy supply chains in general, and in particular, the paper provides a supply chain perspective of pre‐treatment processes, where previous research has focused primarily on technical aspects of torrefaction.

Modern thermal and non-thermal pretreatment techniques, namely, enzymatic treatment, gas phase plasma treatment and ohmic heating have become more pronounced over conventional techniques for enhanced coloured phytochemicals (pigments) extraction. Presently, numbers of pretreatment techniques are available with some unique feature. It is difficult to choose best pretreatment method to be employed for phytochemicals extraction from different sources. Therefore, this paper aims to discuss different modern pretreatment techniques for extraction with their potential results over conventional techniques.

Research and review articles targeting to the thermal and non-thermal pretreatment techniques were collected from Google Scholar. The required information has been tabulated and discussed which included qualities of modern pretreatment techniques over conventional techniques, phytochemical extraction and best pretreatment methods for optimized results.

Every pre-treatment has its own advantages and disadvantages for a particular phytochemical and its extraction from various sources. Enzymes can be used in combinations to enhance final yield like extraction of carotenoids (pectinase, cellulase and hemicellulase) from chillies and lycopene (pectinase and cellulase) from tomato. Utilization of each method depends upon many factors such as source of pigment, cost and energy consumption. CO₂ pretreatment gives good results for carotenoid extraction from algae sources. Ohmic heating can yield high anthocyanin content. Modifications in conventional blanching has reduced final waste and improvised the properties of pigment.

This study comprises collective information regarding modern pre-treatment for extraction over conventional pre-treatments. The study also covers future trends and certain new hybrid approaches which are still less flourished.