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Latent fingerprint deposits on thermal paper sourced from the U.S., China, the U.K., and Australia have been visualized by heating. U.S. and Chinese sourced paper produced two distinct types of fingerprint development. In one type (type 1), the paper dye colors where the deposit is present (as previously reported) and in the other type (type 2) the 'inverse' of this gives paper coloring only in areas not coincident with the deposit. Both development types gave identifiable fingerprints, the majority fading within 24 h of heating. Fingerprint development from U.K. and Australian sourced paper was exclusively type 1 and resistant to fading. Temperatures for fingerprint visualization were higher for U.S. paper (64-71°C) and Chinese paper (75-95°C) than for U.K. and Australian sourced paper (43-50°C). Particularly for Chinese sourced paper, these temperatures were within a few degrees of the normal paper color temperature. A mechanism for type 2 fingerprint development is proposed.

This paper deals with the study of volatile compounds released by recycled paper and board. The aim of the study was to demonstrate the feasibility of headspace procedure coupled to gas chromatography/mass spectrometry (GC/MS) applied to complex paper-based samples together with a chemometric procedure as a powerful method for screening potential volatile contaminants released by the recycled and virgin paper samples. Using this procedure, the identification of virgin or recycled paper could be achieved based on the identification on specific markers of the recycled pulp. Fifteen different samples within virgin and recycled paper were studied. After equilibration, the vapour phase of the samples was analysed by automatic headspace coupled online to GC/MS. The analytical approach for volatile compounds, their identification and the selection of some compounds as markers for recycled pulp are shown and discussed. A discriminate analysis applied to the set of results obtained allows classification of the samples into four different groups according to the content of recycled pulp (0, 10–30 and > 80% of recycled pulp), the surface treatment of the paper (no surface treatment, clay coating and plastic coating), the grammage (from 300 g/m2) and the sample thickness (from 600 µm). The matrix effect on the volatilization of some compounds from the paper samples and the analytical behaviour are also discussed. Copyright © 2009 John Wiley & Sons, Ltd.

This paper presents ongoing work at Australia's largest paper recycler, Visy Pulp & Paper, involving experimental and computational fluid dynamics (CFD) studies to understand paper pulp mixing processes, aimed at identifying means of reducing the large power consumption of the agitators currently used. The key focus of this paper is on the modelling of a pseudo-plastic fluid and the determination of means by which adequate flow circulation can be maintained in such a system. We look at reducing the present agitator speed, at using a larger impeller, and examine the performance of a completely different design. Power consumption reductions of 50%, and perhaps 75–80%, from present levels, appear feasible and could be implemented economically. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.

One of the most interesting and important problems, met during the development of non-pressurized impregnated paper cables for high voltage direct current, arose from the introduction of a long-duration type test at thermal cycles under a DC steady voltage of twice the working voltage. DC cables manufactured according to a traditional paper insulating technique showed during the cooling phase of a thermal cycle a catastrophic fall of the dielectric strength of the order of 50 %. The reason for this fall is analysed both theoretically and experimentally and the way to overcome the obstacle is explained and discussed.

Summary The discussion presents questions regarding the recommended damping scheme from the discussed paper and provides an alternative recommendation. The discussion also requests further explanation on behavioral differences between models incorporating the P-delta and corotational approaches that are presented in the paper. Responses to these questions are presented. Copyright © 2016 John Wiley & Sons, Ltd.

A shape optimization problem for incompressible flows within a stabilized finite element framework is studied. The goal is to develop and test numerical realizations of optimal shape design problems that could be applied to non-trivial industrial problems. The resulting algorithm is applied to the optimization of the geometry of a tapered header in a paper machine headbox. Copyright © 2000 John Wiley & Sons, Ltd.

Inefficient packaging constitutes a global problem that costs hundreds of billions of dollars, not to mention the additional environmental impacts. An insufficient level of packaging increases the occurrence of product damage, while an excessive level increases the packages' weight and volume, thereby increasing distribution cost. This problem is well known, and for many years, engineers have tried to optimize packaging to protect products from transport hazards for minimum cost. Road vehicle shocks and vibrations, which is one of the primary causes of damage, need to be accurately simulated to achieve optimized product protection. Over the past 50 years, road vehicle vibration physical simulation has progressed significantly from simple mechanical machines to sophisticated computer-driven shaking tables. There now exists a broad variety of different methods used for transport simulation. Each of them addresses different particularities of the road vehicle vibration. Because of the nature of the road and vehicles, different sources and processes are present in the vibration affecting freight. Those processes can be simplified as the vibration generated by the general road surface unevenness, road surface aberrations (cracks, bumps, potholes, etc.) and the vehicle drivetrain system (wheels, drivetrain, engine, etc.). A review of the transport vibration simulation methods is required to identify and critically evaluate the recent developments. This review begins with an overview of the standardized methods followed by the more advanced developments that focus on the different random processes of vehicle vibration by simulating non-Gaussian, non-stationary, transient and harmonic signals. As no ideal method exists yet, the review presented in this paper is a guide for further research and development on the topic. Copyright © 2015 John Wiley & Sons, Ltd.

Patterning technology on the paper based on wettability difference for paper-based devices has attracted significant attention for its low cost, easy degradability, and high flexibility. Here, cond ...

An analytical survey of 20 paper and board (PB occasionally, migration estimations overcame the specific migration limits. The chosen analytical methods coupled with a chemometric approach proved to be an effective way to describe the data; it may be concluded that only the simultaneous consideration of several chemicals with a multivariate approach allowed the investigated packaging materials to be distinguished. Copyright © 2014 John Wiley & Sons, Ltd.

The migration of two surrogate contaminants, 1-hydroxycyclohexyl-1-phenyl ketone (184) and benzyldimethyl ketal (651), from different paper into different food simulant (10% ethanol, 95% ethanol and isooctane) through different polymer coating low density polyethylene (LDPE) and polypropylene (PP) was studied. The paper samples were spiked with anhydrous ethanol solution containing the two surrogates and were dried using vacuum dry oven with vacuum degree 0.01 MPa and temperature 55°C and then subjected to migration experiments by using single-sided contact method at 20°C. The concentration of surrogates in 10% ethanol, 95% ethanol and isooctane food simulants were determined by gas chromatography with flame ionization detector after predisposal. Effect factors on migration were discussed from different aspect such as food simulant, paper property, thickness of polymer coating and type of polymer coating. The results showed that the migration rate was faster in fatty food simulant 95% ethanol and isooctane than in aqueous food simulant 10% ethanol, a thicker LDPE coating delayed the migration process of contaminant, paper with lower density and higher porosity would increase migration speed and the barrier property of PP was far away higher than that of LDPE, even if the thickness of LDPE was thicker a lot than PP. Copyright © 2012 John Wiley & Sons, Ltd.

AMOLED on plastic substrates is expected to be the best candidate for foldable display. However, for small bending radius foldable AMOLED display modules, researches on module process and stress resistance material still remain essential and challenging. In this paper, recent work on a 7 inch full-function foldable AMOLED display module is introduced. In addition, the failure modes after 100k times folding cycle under bending radius less than 3mm are also discussed.

A mathematical model was developed to predict the plateau stress of axially loaded paper honeycombs in various humidity environments. It is a simple formula relating the plateau stress to the thickness-to-length ratio of a honeycomb cell, the yielding stress of a cell-wall material tested under a controlled atmosphere [23°C and 50% relative humidity (RH)] and the ambient RH. Paper honeycombs with various thickness-to-length ratios were researched under several levels of RH, and the plateau stress of each kind of paper honeycomb was obtained. The created model was then verified by comparing the predictions with observations. A good agreement between them corroborates the feasibility and accuracy of the model. Predictions by the present model and those by empirical relations were compared as well. A better prediction was obtained using the present model for a wide range of thickness-to-length ratios, suggesting that the present model can replace empirical formulas to provide more accurate and effective predictions of the plateau stress for paper honeycombs. The proposed method can be used to characterize the energy-absorption properties of paper honeycombs in an actual logistic environment, and so can be used to optimize the structural design of paper honeycombs. Copyright © 2010 John Wiley & Sons, Ltd.

Beating vibration phenomenon observed in paper machine roll units is studied. An analytical model of a roll system is described and an expression for the beating frequency is derived. Numerical results are compared to measurements and conclusions are made based on the observations. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The Electrostatic Dust Print Lifter (EDPL) and the Electrostatic Detection Apparatus(2) (ESDA(2)) were compared to determine if both processes could be used to develop footwear impressions of the same or similar quality and in what order they should be used to develop the highest quality footwear impression. The sensitivity of each technique was also evaluated. The quality of the footwear impressions developed was determined by comparing 25 individual characteristics present on the known shoe to the footwear impressions developed using each technique. The footwear impressions were made by stepping on paper placed over several different surfaces, which included: linoleum, industrial Berber carpet, nylon carpet placed over a (3/8)-in. pad, ceramic tile, cardboard, 1-in. foam, 4-in. foam, cement, asphalt, grass, and mulch. Each of the papers placed on these surfaces was developed using the EDPL before the ESDA(2) and vice versa. The sensitivity test for the ESDA(2) was conducted by processing 10 sheets of stacked paper that were stepped on with the known shoe, beginning with the top sheet. The sensitivity test for the EDPL was conducted by processing 10 sheets of paper stepped on with the known shoe in succession. This study determined the footwear impressions developed using the EDPL were of better comparative value than impressions developed with the ESDA(2). On average, 72.4% of the individual characteristics from the known impression were identified on images developed when the EDPL was used first compared with an average of 38.9% when the ESDA(2) was used first. Therefore, if only one technique is used, the EDPL should be chosen. The sensitivity test determined the ESDA(2) develops high-quality footwear impressions on only the top sheet of paper. No footwear impressions were developed on any sheets under the top sheet of paper. The sensitivity test also determined the EDPL results increase in quality as the amount of dust residue decreases on the surface.

Two out-of-plane buckling criteria for paper honeycomb are proposed by analysing the structure properties and the collapse mechanism of paper honeycomb: these are based on the peeling strength and ring crush strength of the chipboard wall. Taking into account the orthotropic, initial deflection and large deflection properties of the chipboard wall, the two new mechanical models and the calculation methods are developed to represent the out-of-plane critical load of paper honeycomb. Theoretical calculations and test results show that the models are suitable for describing the collapse mechanism of paper honeycomb. The peeling strength and ring crush strength determine the critical buckling load of paper honeycomb in different stretch phases. The out-of-plane critical buckling load can be predicted when the two models are integrated. Copyright © 2005 John Wiley & Sons, Ltd.

The innovation of ITRI's roll-to-roll (R2R) technology is capable of handling 100 μm ultra-thin flexible glass (UTFG) with in-house designed equipment. By applying this R2R technology on roll-UTFG, the total thickness of touch panel module with 0.4 mm cover lens can be reduced to 0.6 mm only. This complete solution provides a reliable and cost-effective manufacturing approach making commercialization in the near future.

The bushing of a transformer is one part of the transformer system, but is as vital as the transformer itself because it forms a part of the main circuit. Deterioration and abnormal condition of the bushing possibly cause its destruction, shortage of the main circuit to the Earth, and fire in the systems, so that diagnosis of the bushings is thus very important. At present, mainly visual inspection from outside of the bushing is carried out. Inspection of the inside condition of the bushing by dissolved gas analysis of the inside oil is done only as sampling for selected bushings because it is difficult due to the sealed construction of the bushings. Therefore, a simple diagnostic method for bushings has been expected for a long time. In Eastern Europe, the RVM (Return Voltage Measurement) method based on scanning the polarization spectra was applied to the oil–paper insulation systems inside the transformer as a diagnostic method. In this paper we investigate theoretically the principle of the RVM method applied to bushings with the same oil–paper insulation systems as the transformer by using the equivalent circuit, and the possibility of using this novel diagnostic method for condenser-type bushings is demonstrated by a model experiment. © 1999 Scripta Technica, Electr Eng Jpn, 130(1): 21–29, 2000

IMPACT OF THE PAPER This paper1 addressed a very specific topic and by itself would not have had much impact in the intervening years. However, most of the paper's content was subsequently included in an extensive report on the Damage Tolerance (DT) properties of aluminium alloys.2 This report enabled guidelines for flight simulation fatigue crack growth testing to be formulated.3,4

The friction behaviour of wet clutches for automatic transmission applications strongly influences the dynamic behaviour of the entire machine or vehicle including the transmission. The wear, but also the friction curve, determines the lifetime of the clutch. The role of wear is obvious. The friction coefficient of the material couple friction plate/separator plate decreases with number of engagement cycles. As a result, the possible torque of the transmission decreases with time. Under a certain threshold, the clutch has to be revised. But because manufacturers tend to oversize their clutches the decrease in friction coefficient does not yield a limitation to the lifetime of the clutch. In this paper, both SAE#II and pin-on-disk tests are used to investigate the wear and friction characteristics of the friction material. Although the pin-on-disk tests fail in correctly reproducing the wear rate of the SAE#II tests, they can be used for a qualitative analysis of the influence of material parameters and operating conditions on both friction coefficients and wear rate. © 2001 Elsevier Science B.V. All rights reserved.

The concept of using paper in medical packaging has been accepted widely. as it provides the essential permeability to allow ingress of the sterilising media whilst preventing the post-penetration of bacteria. thereby maintaining sterility of the medical device itself. In Europe this widespread application of paper has demanded the introduction of proper standards for sterilization papers and converted items, such as bags and pouches. In this article these standards are discussed, i.e. British Standards, German DIN 58953, French Pharmacopoeia and Eucomed (European Confederation of Medical Suppliers Association). Comparisons of these standards, including results of our testing, also are presented t o underline the essential differences between specifications for the same grade of paper. In particular, special note is made in the case of air permeability of papers used for gas sterilization. The most reasonable solution is put forward by Eucomed, in which permeability performance is more fully addressed. The principles of various methods for the determination of microbial barrier performances of sterilization papers also are described and some comments in this respect are given.

A novel approach to fabricate supercapacitors (SCs) via vapor printing, specifically oxidative chemical vapor deposition (oCVD), is demonstrated. Compared to stacking multiple layers into a SC, this method enables the monolithic integration of all components into a single-sheet substrate, minimizing the inactive materials and eliminating the possibility of multilayer delamination. Electrodes comprised of pseudocapacitive material, poly(3,4-ethylenedioxythiophene) (PEDOT), are deposited into both sides of a sheet of flexible porous substrate. The film deposition and patterning are achieved in a single step. The oCVD PEDOT penetrates partially into the porous substrate from both surfaces, while leaving the interior of the substrate serving as a separator. Near the surface, the PEDOT coating conforms to the substrate's structure without blocking the pores, resembling the substrate's intrinsic morphology with high surface area. The porously structured PEDOT coating, paired with in situ ion gel electrolyte synthesis, gives enhanced electrode-electrolyte interfaces. The monolithic device demonstrates high volumetric capacitance (11.3 F cm-3 ), energy density (2.98 mWh cm-3 ), and power density (0.42 W cm-3 ). These outstanding performance metrics are attributed to the large loading of active materials, minimization of inactive materials, and good electrode-electrolyte interfaces. SC arrays can be printed on a single substrate without the use of wire interconnects.

This note is a corrigendum of the paper ‘Linear Time Varying Model Predictive Control and its Application to Active Steering Systems: Stability Analysis and Experimental Validation’, published on the volume 18, issue 8, pages 862–875 of the International Journal of Robust and Nonlinear Control in 2008. Next we point out a technical error in the proof of Lemma 2 of the paper, and provide the corrected version of the lemma. Copyright © 2011 John Wiley & Sons, Ltd.

Research results are commonly circulated on the occasion of congresses or by publication in technical journals. steel research, the scientific journal edited by the Verein Deutscher Eisenhuttenleute, VDEh - The German Iron and Steel Institute, and the Max-Planck-Institut fur Eisenforschung, MPI, presents the latest results of fundamental research in the fields of process metallurgy, metal working and materials science as far as the material steel is concerned. Formerly well-known as “Archiv fur das Eisenhuttenwesen”, steel research looks back on 70 years of experience in worldwide exchange of technological basics. In 1995, the editors decided to offer a Best Paper Award with 1.000 US-$ purse and a pretty diploma. Considering all papers published in the 71st volume of steel research in the year 2000 the Editorial Board chose a two-part publication discussing a subject of materials technology.

In 1977, an LCD (Liquid Crystal Display) panel using ACF (Anisotropic Conductive Film) was manufactured for the first time, in history. Since then, ACF has been recognized as an indispensable material for assembling FPD (Flat Panel Display) modules. Due to the remarkable developments in LCD, and expansion of the field of LCD applications, the properties and features of ACF have simultaneously been improving (e.g., reliability of interconnection, compatibility for finer pitch patterning, and demand for both low-temperature and short processing time during main bonding process) and have assumed a role as an important element contributing to the growth of the FPD industry. In recent years, ACF has also had seen an expansion of its usage in a wide variety of applications for electric interconnect, not only in FPD modules, but also for Semiconductor Packaging, RF-ID and replacement for conventional mechanical connecter.

Sustainable materials like paperboard can substitute for crude oil‐based polymers in packaging applications and, by doing that, reduce the negative environmental impacts caused by plastic waste. For a broader application in the packaging industry, the forming of paperboard needs to overcome its limited forming behaviour and barrier properties. The presented work aims to influence the forming behaviour of uncoated and polyethylene terephthalate (PET)‐coated paperboard with additives like water, gelatin and soap. Furthermore, the differences in the mechanical behaviour of coated and uncoated materials are investigated. For the studies, tensile, bulge and forming tests were combined with different optical measurement methods. The investigations showed that the overall forming behaviour is affected by the mentioned additives and can be improved. Additionally, the interaction of the coating and substrate paper is investigated under different load conditions. Post-print / Final draft

Over the past years, eco‐friendly packaging solutions such as moulded pulp have resonated with a growing number of consumers. Among all of them, the thermoformed products make use of the most recent manufacturing approach that produces high‐quality, thin‐walled items. However, it remains an underresearched area, and the development of an efficient and precise manufacturing process is fundamental in order to increase the implementation of sustainable packaging.With the purpose of setting a step towards in the standardization of design and testing practices of eco‐friendly packaging, this work focused on the characterization of the thermoforming process of moulded pulp products and their characteristics. Three different analyses were carried out for this purpose, covering the dewatering efficiency of the process, a quantification of the moulding geometrical accuracy, and an analysis of the internal microstructure of the parts. Experimental results and statistical analysis show that the dewatering efficiency is mainly governed by the mould's temperature while the duration of the contact time is not influential. In the second investigation, the geometrical accuracy of the mouldability of microfeatures was assessed. The process appeared to be dependently related to the pulp type employed. Finally, the internal microstructure was documented using X‐ray computed tomography. The analysis shows an increase in the internal void fraction linked with an increase in the mould's temperature.The role of the water change of phase in the thermoforming process is also discussed by reference to the work conducted on impulse drying.

A 0.25 m3 laboratory repulper was built for the purpose of determining which variables (pulp type, rotor tip speed, pulp suspension temperature, rotor design, rotor to extraction plate clearance, power to vat volume ratio, and pulp suspension consistency) affect the specific energy (kW-h/ton) required for repulping. Scale replicas of 3 commercial repulper rotors were constructed to test the effect of rotor geometry on repulping specific energy. The pulp types used included kraft aspen, C-flute corrugated cardboard, office printing paper, and unbleached paper towel. The energy required for repulping was found to vary with pulp type, temperature, consistency, and rotor design. It was found that a given material at a given temperature and consistency requires a unique quantity of energy to be repulped independent of the rate of energy addition. It was also found that repulper rotors show Reynolds independence at rotor tip speeds greater than 12m/s. It was found that the specific energy consumption in a 0.25 m3 laboratory repulper was identical to that for a 15 m3 repulper given the comparison was made with identical pulp types, temperatures, consistencies, and rotor designs.

Eco-friendly packaging such as moulded pulp products have gained commercial importance in the recent years. However, it remains a greatly under-researched area, and there is an arising need to consolidate the best practices from research and industry in order to increase its implementation. The goal of this paper is to give an overview of the main aspects involved in the manufacture of moulded pulp products. This includes a classification of moulded pulp products, historical and current applications, production processes, materials, mechanical properties and environmental sustainability. Moreover, based on the latest research in the field, an innovative drying technique that utilizes concepts derived from impulse drying is presented, and the implementation of this process technology is discussed. Copyright © 2017 John Wiley & Sons, Ltd.

Trametes versicolor laccase papers were prepared, and their suitability was tested for anticounterfeiting and oxygen indicator concepts in packaging applications. Laccase was coated and printed onto paper with a flexographic ink base, a sulfo polyester resin, Hydro-Rez 1100D (HZ1100D). Laccase remains active on paper with flexographic ink HZ1100D after printing with flexographic press. Colour change of papers was observed when 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) solution was applied to the paper. A strong colour change to dark green was obtained on the papers prepared by coating or printing of laccase with HZ1100D onto EUCA paper. EUCA paper appeared to be well suited for laccase-based indicator applications because it remained rough even after ink deposition, allowing rapid absorption of ABTS solution. Finally, the indicators demonstrated to work as oxygen indicators in a package. Indicator colour was changed when oxygen was leaked to the package. As a conclusion, the laccase papers described here would be well suited for various indicator applications and could be produced using flexographic printing, allowing large scale manufacturing. Copyright © 2014 John Wiley & Sons, Ltd.

Experiments were made with a laboratory apparatus for forming paper sheets into double-curved structures. The purpose was to learn more about the design criteria for forming of paper materials into ...

The condition assessment of the 190 MVA, OFWF, step-up generator transformer was performed by the mapping of degree of polymerization (DP). The transformer was taken out of service after 36 years and the active part, (transformer core and windings), was removed from the tank for close examination due to the major thermal fault at the transformer core. The transformer insulation consisted of two different materials, i.e. winding insulation was the thermally upgraded paper and spacer-pressboard system was Kraft paper. The temperature mapping is also shown, where the temperature estimation is based on the paper aging kinetics, transformer loading and insulation operating history. New equation for the relative aging rate is given considering all insulation conditions providing possibility of counting transformer loss-of-life more accurately. Copyright © 2010 John Wiley & Sons, Ltd.

In this paper, an “equivalent paper machine” is presented which possesses the features of both the fourdrinier machines and cylinder machines, and a universal model is developed by mechanism analysis. The model is not only an external description as often obtained by system identification, but an internal one in which internal process variables are included. Experiments show that the model agrees closely with the plant data.

Low consistency refining is primary means of improving the paper quality by imparting energy to fibres through repeated fibre–bar interactions. Useful part of the energy modifies the morphology of fibres and the remaining, no-load power, overcomes the hydraulic, pumping and mechanical losses in the refiner. In this study, effect of consistency, operational and plate design parameters on no-load power was experimentally determined on two pilot scale refiners with different diameters. Obtained data were used to provide a statistical model for prediction of no-load power. To study the effect of diameter and groove depth, no-load power of some mills were collected.

Peel yellowing and loss of fruit mass reduce the useful life of acid limes and limit their commercialization. The goal of the present study was to prolong the post-harvest preservation of acid limes using wax and packaging. Fruits were harvested, selected, disinfected, treated with fungicide, coated with Carnauba wax and placed in cardboard boxes wrapped with different plastic packaging. A fruit lot treated only with wax coating was used as a control. The fruits were stored at 10°C for 24 days followed by 6 days at 20°C. The gas atmosphere inside the packages was analysed during storage. The loss of mass, color index, titratable acidity, and total chlorophyll, ascorbic acid, soluble solids, acetaldehyde and ethanol concentrations of the fruits were measured. The combined use of wax coating and plastic Cryovac® D-955 (Cryovac Brasil Ltda, Sao Paulo, Brazil) and Vegetal Pack® (Eletropolimeros do Brasil Ltda, Sao Paulo, Brazil) films resulted in better post-harvest preservation of acid limes compared with only wax coating because the combined treatment maintained the green peel color following 30 days of storage in addition to resulting in lower loss of mass and maintaining chemical characteristics adequate for commercialization. The LDPE (low density polyethylene) and Xtend® packaging (Stepac Brasil Ltda, Sao Paulo, Brazil), although they prevented peel degreening, did not result in an adequate atmosphere to maintain the quality of limes due to the accumulation of high concentrations of acetaldehyde and ethanol, especially for the LDPE packaging. LDPE drastically changed the atmosphere surrounding the fruit, resulting in loss of the characteristic pulp color, in addition to conferring an alcohol odor. Copyright © 2015 John Wiley & Sons, Ltd.

Fully matured fresh guava fruits (Lucknow-49) were precooled at 10 °C for 1 h and pretreated with 500-ppm benomyl for 5 min. The fruits were packed in 25-µm and 50-µm LDPE bags with active modified atmosphere packaging of 3% O2 + 5% CO2, 6% O2 + 5% CO2 and 9% O2 + 5% CO2 gas concentrations and stored at 5 ± 1 °C and 10 ± 1 °C temperatures as well as non-packaged as control. The shelf life of guava could be increased up to 42 days by packaging in 50-µm LDPE bags with a gas concentration of 9% O2 + 5% CO2 and stored at 10 °C without much change in physical, biochemical and sensory characteristics. Physico-chemical changes viz., PLW, pulp to peel ratio, firmness, TSS, total sugar, ascorbic acid and titratable acidity were observed minimum for fruits packed in 50-µm LDPE bags at 3% O2 + 5% CO2 gas concentration at 5 °C storage temperature, but sensory score decreased drastically after 21 days of storage. Chilling injury was observed for the fruits packed at 5 °C storage temperature after 21 days of storage, and it was severe in 25-µm LDPE bag at later stage. Control fruits over-ripened with the highest weight loss (12.47%) on 6 days of storage and discarded from the storage. Copyright © 2014 John Wiley & Sons, Ltd.

Tannins and pH are often cited as factors that affect the corrosiveness of wood yet there are few data to confirm these statements. The purpose of this paper is to systematically investigate the effect of tannins and pH on corrosion of metals in wood. Four wood species known to vary in both their pH and extractives were chosen and extracted with water. The pH, tannin content, and corrosion rate of carbon steel were determined for each extract. To test if pH and tannin were the only factors influencing corrosion, “synthetic” extracts were made by adding tannins to distilled water and adjusting the pH. At a given pH, increasing the tannin content inhibited corrosion and at a given level of tannin content, lowering the pH increased corrosion. An isocorrosion map as a function of pH and tannins was developed by using simple kinetic models to extrapolate the data. The data may be useful in estimating the relative corrosiveness of new, nonmetallic wood preservatives based upon the chemistry of naturally durable wood species.