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This paper aims to investigate the tribological behavior and online infrared spectra of three types of lubricating oils containing dinonyl diphenylamine (DNDA) antioxidant, which are mineral oil (MO), poly alpha olefin (PAO) and trimethylolpropane trioleate (TMPTO), during the friction process at high temperature (temperature rising at first and isothermal holding afterwards).

A platform of low speed four-ball tribometer equipped with a temperature controller combined with infrared spectrometer was established. MO, PAO and TMPTO base oils were mixed with 1.0 Wt.% DNDA antioxidant, coded as MO_a, PAO_a and TMPTO_a in sequence. The friction coefficient and online infrared spectra of the oils were tested during the friction process of temperature rising at first and isothermal holding afterwards, and the wear tracks of the upper balls were measured using a confocal scanning optical microscope.

The results indicated that the DNDA antioxidant was depleted to reduce the generation of alcohols and carbonyl products, and the depletion rate of DNDA followed the sequence of MO_a > PAO_a > TMPTO_a. In the temperature rising friction process, the critical transition of friction coefficient was confirmed. The addition of DNDA antioxidant reduced the temperature of the oils at the critical transition of friction coefficient, and the temperature followed the sequence of TMPTO_a > PAO_a > MO_a. After the critical transition, the friction coefficient was first increased and then declined to a steady value; the friction coefficient of MO_a increased and declined first, followed by PAO_a and TMPTO_a. In the steady stage of friction, there was no obvious effect of DNDA on the friction coefficient of the oils. Moreover, DNDA enhanced the wear properties of MO_a and PAO_a; no obvious improvement was revealed for the wear property of TMPTO_a.

The established platform of low speed four-ball tribometer combined with infrared spectrometer successfully realized online testing of the structure changes of lubricating oil during high temperature friction, which can give some reference on the oxidation and friction researches of lubricating oil.

This paper aims to investigate the thermal oxidation behavior of trimethylolpropane trioleate (TMPTO) base oil when exposed to Fe surfaces.

Samples of TMPTO bulk oil were placed in Fe vessels and heated in an oven to accelerate the oxidation at different time intervals, while others were placed in glass vessels and used as experimental controls. Subsequently, the physicochemical properties of the oxidized TMPTOs, including the kinematic viscosity and acid value, were measured and a structural analysis was conducted using the Raman and Fourier transform infrared (FTIR) techniques.

The results demonstrate that the TMPTO bulk oil exhibited an exponential increase in the kinematic viscosity along with the increasing acid value over the oxidation time. The Fe surface significantly increased the kinematic viscosity of TMPTO, while only mildly impacting its acid value compared with the experimental controls. The structural analysis results of the TMPTO suggest that the C = C and = C-H bonds were the vulnerable sites. Furthermore, the results suggest that the Fe surface evidently accelerates the chemical reactions of the C = C and the = C-H bonds, and less alcohols and more carbonyl products were identified in the oil samples that were heated in the Fe vessels.

The results demonstrate that the Fe surfaces affected the oxidation behavior of the TMPTO base oil, and an interaction mechanism between the Fe and the TMPTO is developed.

Compilation of numeric data has been of interest to mankind since ancient times. Collections of astronomic observations permitted the production of systematic calendars for great nations like the Mayans, Egyptians, Babylonians and Jews. Extensive sets of data were available to early navigators and pioneer physicists of medieval times. A well known example of data compilation was the celebrated Alfonsine Tables. The tables were completed in 1252 under the direction of Isaac ben Said and Yehuda ben Moshe Cohen during the rule of Alfonso X. of Castile. For three hundred years this was considered to be the best planetary data collection. Another famous astronomical data compilation was Caroline Herschel's Catalogue of Stars published in 1798. In the last decade there has been an increased need for precise information by government agencies, private industries, the business world and academic institutions. The continuing acknowledgement of the need for quantitative data contributed to the quick development and marketing of many databases that contain numerical and other factual information.

Library managers are becoming increasingly concerned about document delivery systems because the means to identify and locate materials has improved faster than the ability to provide the materials and because a cut‐back in library budgets is forcing libraries to borrow or obtain more material from other sources. A new SPEC kit (no. 82, March 1982) has been produced on document delivery systems in use in the Association of Research Libraries. The September 1981 survey covered two categories of service: internal delivery — disseminating locally‐owned materials to users, and external delivery — acquiring materials from an outside source for local users. Some ninety ARL libraries responded to the survey by providing materials and information describing the methods they employ. These include telefax, requests via electronic mail and OCLC's interlibrary loan subsystem and online ordering from data‐bases. SPEC kit #82 contains twenty‐six documents, (101 pages) and is available for $15 (prepaid) from Systems and Procedures Exchange Center, OMS/ARL, 1527 New Hampshire Ave., NW, Washington DC 20036, USA.

The monitoring of water build‐up in hydraulic, cooling and lubricating oils is routinely carried out in many laboratories, using various Karl Fischer titration and infrared techniques. The complexity and specialized nature of these techniques does not lend itself to the more credible online, on‐site testing demanded by good predictive maintenance practices.

The US Copyright Office has released the final report Libraries, Publishers and Photocopying, which describes in detail the volume and characteristics of photocopying and interlibrary loan in public, academic, federal and special libraries in the US. Also described are results of a survey of US publishers about their serial and book income and photocopying permission requests, as well as the results of personal interviews conducted with library users about their own photocopying done on library coin‐operated photocopying machines. The study, conducted under contract by King Research, Inc., of Rockville, Maryland, was designed to provide data as input to the US Copyright Office's five‐year review of the new US copyright law which took effect on January 1st, 1978. Copies of the final report ($25 in the US, $30 elsewhere) are available from King Research Inc., PO Box 71, Rockville, Md 20850, USA.

This study aims to describe the design and synthesis of two novel azo and imine chromophores-based dyes derived from two different aldehydes with intramolecular colour matching that are pH sensitive.

The visible absorption wavelength (λ_max) was extended when azo chromophore was included in imine-based systems. The dyed patterns created sophisticated colour-changing paper packaging sensors with pH-sensitive chromophores using alum as a mediator or mordant. Due to the tight adhesive bonding, the dyes on paper’s cellulose fibres could not be removed by ordinary water even at extremely high or low pH, which was confirmed by scanning electron microscopy analysis. The dyed patterns demonstrated an evident, sensitive and fast colour-changing mechanism with varying pH, from pale yellow to red for Dye-I and from pale yellow to brown-violet for Dye-II.

The λ_max for colour changing was recorded from 400 to 490 nm for Dye-I, whereas from 400 to 520 for Dye-II. The freshness judgement of food was checked using actual experiments with cooked crab spoilage, where the cooked crab was incubated at 37 ^oC for 6 h to see the noticeable colour change from yellow to brown-violet with Dye-II. The colour-changing mechanism was studied with Fourier transform infrared (FTIR) spectra at different pH, and thin layer chromatography, nuclear magnetic resonance and FTIR spectroscopy studied the desired structure formation of the dyes. Potential uses for smart packaging sensors include quickly detecting food freshness during transportation or right before consumption.

1. Two novel azo-imine dyes have been synthesized with a pH-responsive effect. 2. The pH-responsive mechanism was studied. 3. The study was supported by computational chemistry using density functional theory. 4. The obtained dyes were used to make pH-responsive sensors for seafood packaging to judge the freshness.

Currently, Mauritius is adopting landfilling as the main waste management method, which makes the waste sector the second biggest emitter of greenhouse gas (GHG) in the country. This presents a challenge for the island to attain its commitments to reduce its GHG emissions to 30% by 2030 to cater for SDG 13 (Climate Action). Moreover, issues like eyesores caused by littering and overflowing of bins and low recycling rates due to low levels of waste segregation are adding to the obstacles for Mauritius to attain other SDGs like SDG 11 (Make Cities & Human Settlements Inclusive, Safe, Resilient & Sustainable) and SDG 12 (Guarantee Sustainable Consumption & Production Patterns). Therefore, together with an optimisation of waste collection, transportation and sorting processes, it is important to establish a solid waste characterisation to determine more sustainable waste management options for Mauritius to divert waste from the landfill. However, traditional waste characterisation is time consuming and costly. Thus, this chapter consists of looking at the feasibility of adopting machine learning to forecast the solid waste characteristics and to improve the solid waste management processes as per the concept of smart waste management for the island of Mauritius in line with reducing the current challenges being faced to attain SDGs 11, 12 and 13.

To review the use of near‐infrared (NIR) spectroscopy in the process control of foodstuffs.

Presents two spectroscopy products used in the production environment: a single‐board system aimed at OEMs, and a complete fibre‐optic spectrometer ready for the end‐user. Gives examples of applications within the food and drink industry.

Finds that these instruments are fast, effective and inexpensive, and rugged enough for the processing environment.

Draws attention to the potential of NIR spectroscopy outside the confines of the laboratory.