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This paper aims to study the mass loss of three-dimensional (3D) printed materials at high temperatures. A preconcentration and analysis technique, static headspace gas chromatography-mass spectrometry (SHS-GC-MS), is demonstrated for the analysis of volatile compounds liberated from fused deposition modeling (FDM) and stereolithography (SLA) 3D printed models under elevated temperatures.

A total of seven commercial 3D printing materials were tested using the SHS-GC-MS approach. The printed model mass and mass loss were examined as a function of FDM printing parameters including printcore temperature, model size and printing speed, and the use of SLA postprocessing procedures. A high temperature resin was used to demonstrate that thermal degradation products can be identified when the model is incubated under high temperatures.

At higher printing temperatures and larger model sizes, the initial printed model mass increased and showed more significant mass loss after thermal incubation for FDM models. For models produced by SLA, the implementation of a postprocessing procedure reduced the mass loss at elevated temperatures. All FDM models showed severe structural deformation when exposed to high temperatures, while SLA models remained structurally intact. Mass spectra and chromatographic retention times acquired from the high temperature resin facilitated identification of eight compounds (monomers, crosslinkers and several photoinitiators) liberated from the resin.

The study exploits the high sensitivity of SHS-GC-MS to identify thermal degradation products emitted from 3D printed models under elevated temperatures. The results will aid in choosing appropriate filament/resin materials and printing mechanisms for applications that require elevated temperatures.

This paper aims to systematically demonstrate a methodology to determine the relative and absolute encapsulation efficiencies (α_Re and α_Ab) for thermally- and chemically-robust inorganic pigments, typically like ZrSiO₄-based pigments, thereby enhancing their coloring performance.

The authors designed a route, surplus alkali-decomposition and subsequently strong-acid dissolution (SAD2) to completely decompose three classic zircon pigments (Pr–ZrSiO₄, Fe₂O₃@ZrSiO₄ and CdS@ZrSiO₄) into clear solutions and preferably used inductively coupled plasma-optical emission spectrometry (ICP-OES) to determine the concentrations of host elements and chromophores, thereby deriving the numeric data and interrelation of α_Re and α_Ab.

Zircon pigments can be thoroughly decomposed into some dissoluble zirconate–silicate resultants by SAD2 at a ratio of the fluxing agent to pigment over 6. ICP-OES is proved more suitable than some other quantification techniques in deriving the compositional concentrations, thereby the values of α_Re and α_Ab, and their transformation coefficient K_RA, which maintains stably within 0.8–0.9 in Fe₂O₃@ZrSiO₄ and CdS@ZrSiO₄ and is slightly reduced to 0.67–0.85 in Pr–ZrSiO₄.

The SAD2 method and encapsulation efficiencies are well applicable for both zircon pigments and the other pigmental or non-pigmental inhomogeneous systems in characterizing their accurate composition.

The authors herein first proposed strict definitions for the relative and absolute encapsulation efficiencies for inorganic pigments, developed a relatively stringent methodology to determine their accurate values and interrelation.

The first Aslib Annual Lecture will be given at 6 p.m. on Wednesday 5th April at the Lecture theatre of the Royal Institution of Great Britain, 21 Albermarle Street, London W1 by Dr W. E. Batten. The chair will be taken by Sir John Wolfenden, CBE, Vice‐Chancellor of the University of Reading.

It often becomes necessary to analyse a grease for a variety of reasons:

The 1957 MOTOR SHOW, OR GIVEN ITS FULL title, The 42nd International Motor Exhibition, will be officially opened at Earls Court, London, on October 16th at 12 noon by the Prime Minister, The Rt. Hon. Harold Macmillan, M.P. The Exhibition will be open to the public from 10 a.m. to 9 p.m. daily, (except Sundays) from the 16th to the 26th. Admission charges for the opening day, and also for Tuesday, 22nd are £1 before 5 p.m. and 10s. 0d. after 5 p.m. On all other days prices are 5s. 0d. before 5 p.m. and 2s. 6d. after.

This paper aims to find a suitable solution to degrade the C.I. Reactive Red 24 (RR24) dyeing wastewater by using sodium persulphate to recycle water and inorganic salts.

The effects of temperature, the concentration of inorganic salts and Na₂CO₃ and the initial pH value on the degradation of RR24 were studied. Furthermore, the relationship between free radicals and RR24 degradation effect was investigated. Microscopic routes and mechanisms of dye degradation were further confirmed by testing the degradation karyoplasmic ratio of the product. The feasibility of the one-bath cyclic dyeing in the recycled dyeing wastewater was confirmed through the properties of dye utilization and color parameters.

The appropriate conditions were 0.3 g/L of sodium persulphate and treatment at 95°C for 30 min, which resulted in a decolorization rate of 98.4% for the dyeing wastewater. Acidic conditions are conducive to rapid degradation of dyes, while ·OH or SO₄⁻· have a destructive effect on dyes under alkaline conditions. In the early stage of degradation, ·OH played a major role in the degradation of dyes. For sustainable cyclic dyeing of RR24, inorganic salts were reused in this dyeing process and dye uptake increased with the times of cycles. After the fixation, some Na₂CO₃ may be converted to other salts, thereby increasing the dye uptake in subsequent cyclic staining. However, it has little impact on the dye exhaustion rate and color parameters of dyed fabrics.

The recommended technology not only reduces the quantity of dyeing wastewater but also enables the recycling of inorganic salts and water, which meets the requirements of sustainable development and clean production.

Inter-fibre cohesion is regarded as an important property of assemblies, such as slivers, made of wool or any other fibres, with respect to the processing in carding, drawing (gilling) and spinning. In this paper, the results of the multiple regression analyses, and their validation, are presented to show that a strong relationship exists between the sliver cohesion (measured as sliver tenacity and sliver specific energy-to-break in a long-gauge tensile test) and a combination of the standard wool properties, such as bulk, mean fibre length (Barbe), mean fibre diameter and medullation content, used for the objective blend specification of New Zealand wools for marketing and processing.

Notes difficulties related to devising specific functional tests of vitamin C status. Looks at approaches used in the study of the mechanisms of vitamin C absorption and their limitations. Outlines the goals of a MAFF project to begin in 1997; these being, for example, to improve current analytical procedures in this area.

Human selection of periodical references from the full text, for inclusion in the Mass Spectrometry Bulletin, is compared with the retrieval from the same source material by the mechanized current awareness SDI services of CT and ASCA. Results show human selection to have retrieved substantially more references than SDI using brief, high relevance profiles. Experiments with CT using a larger profile show an increase in recall but a drop in precision. Precision is assessed in relation to the selection/rejection policy for the Bulletin, which is briefly discussed. The effectiveness of the SDI services as a means of indicating references in periodicals outside the range of those examined in detail is also discussed.

This study aims to analyze the antioxidant properties of the Mediterranean diet and describe methods that are used in clinical studies to assess its role in reducing oxidative stress.

The review presents the results of interventional and observational clinical trials aimed at assessing the influence of the Mediterranean diet on the level of enzymatic and non-enzymatic antioxidants, as well as the total blood antioxidant capacity.

The Mediterranean diet as a varied diet can be a better way to provide antioxidants to the body than supplements. Individual compounds administered in an isolated form can give the opposite effect to the expected, stimulating oxidative stress. The administration of antioxidants in the form of supplements instead of a varied diet is also associated with a lack of synergism of action. In studies on the importance of the Mediterranean diet in the reduction of oxidative stress, single markers are used to measure oxidative damage, the activity of enzymatic antioxidants and the concentration of individual non-enzymatic antioxidants. At the same time, the need to find markers that would assess the level of oxidative stress and the body’s antioxidant capacity more comprehensively is emphasized.

It should be taken into account that differences between in vivo and in vitro results may result from the fact of various factors, including genetic, smoking, intestinal microflora or diet composition. It is also necessary to answer the question about which marker or set of markers could in the most comprehensive way to assess the level of oxidative stress and the body’s antioxidant capacity.

The literature review shows not only the source of antioxidants in the Mediterranean diet. This paper also presents a critical approach to markers that allow the assessment of the antioxidant properties of the diet.