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Freeze-thaw cycles in combination with long-term moisture exposure and traffic is a major threat to the performance of asphalt pavements. To enable characterisation and understanding of the damage ...

Crispness is the most appealing characteristic of dry food products. However, the term crispness has different subjective meaning among consumers. This study aims to quantitatively measure the crispness of potato crisp by performing compression test on a single specimen, and analyzing the compressive behavior, i.e., compressive strain energy. The crispness of the specimens were differentiated by changing the moisture exposure durations, which are 0, 1, 2, 3, 6 hours, in a room and ambient condition. The measured load and displacement data were transformed into stress and strain curves. The strain energy for every 1% strain increment was calculated and investigated to determine the crispness. The crispness difference among specimens of 0, 3, and 6 hours groups was significantly perceived at 8% of strain. It was revealed that the 3 and 6 hours of room air exposure could decrease the crispness by 17% and 45%, respectively. This suggests the compressive strain energy at a certain strain can be an indicator of crispness. This experimental study is expected to evolve food engineering by proposing a simple yet precise crispness measurement method for dry food.

Background Upper extremity fractures requiring cast immobilization are exceedingly common, especially in the pediatric population. Studies have shown improved outcomes when patients can participate in water-based activities while casted. However, waterproof cast material is not feasible in all clinical settings and wet cast complications remain a source of morbidity and expense. External cast protectors play an important role in preventing wet casts, but the efficacy of various commercially available brands during relevant water-based activity remains unknown. Purposes To determine if there are differences in the rate and extent of moisture exposure for four commercially available cast protectors using a mechanized cast arm model and human volunteers. Methods A mechanized arm model was developed with four implanted humidity sensors. Cast protectors were applied over the arm, the model was submerged in water, and moved back and forth, simulating cast-wearers’ motion. Data regarding humidity was recorded for successive 10-minute trials. Trials were analyzed using a mixed effects linear model to determine change in humidity over time. The top and bottom performing cast protectors were then applied to four adult volunteers prior to thirty minutes of swimming. Questionnaires regarding comfort and a qualitative assessment of cast wetness using a chemical color indicator were completed. Results 372 instances of sensor data from 96 10-minute trials was collected. The CVS, SealTight and Walgreens brands showed significant increases in humidity beginning at 10, 20 and 20 minutes, respectively. DryPro showed no significant increase in moisture level up to 50 minutes. In successive trials up to 120 minutes, DryPro showed only a 2% increase in moisture. In human subjects testing, 3/4 casts underneath CVS protectors had some degree of wetness-related color change that would require cast change as compared to 0/4 casts underneath DryPro protectors. Conclusions Significant differences exist between commercially available cast protectors. Vacuum-sealed protectors performed best in both mechanical and human subject portions of this study and allowed minimal change in humidity for extended periods of sequential water immersion. Their cost is notably less than management of a wet cast. Lower-performing products may expose cast-wearers to an increased risk of wet cast complications.

Glass/Vinylester composite laminates are comprehensively characterised to assess its impact response behaviour under moisture exposure in marine structures. An instrumented drop weight impact machine is utilised to determine the impact responses of dry and immersed specimens in normal, salted and sea water. The specimens, which had three different thicknesses, were subjected to water exposure for a very long period of over 20 months before tested in a low-velocity impact experiment. Water uptake was measured primarily to study the degradation profiles of GRP laminates after being permeated by water. Matrix dissolution and interfacial damage observed on the laminates after prolonged moisture exposure while the absorption behaviour was found typically non-Fickian. The weight of the composite plates firstly increased because of water diffusion up to month 15 and then decreased due to matrix degradation. The specimens with 3, 6 and 9 mm thickness exhibited maximum water absorption corresponding to 2.6%, 0.7% and 0.5% weight gain, respectively. In general, the results indicated that water uptake and impact properties were affected by thickness and less by water type. Impact properties of prolonged immersed specimens reduced remarkably, and intense failure modes detected almost in all cases. The least sensitive to impact damage were wet specimens with 9 mm thickness as they indicated similar maximum load and absorbed energy for different impact energies.

Bonding strength between asphalt and aggregate is considered an important feature that governs the future performance of flexible pavements. This study investigated five factors that have the poten...

Slabs of polymer composite materials (PCMs) based on glass, carbon, and organic fillers and various binders were made according to one technological molding mode. The main methods for determination of the effects of thermal and moisture factors on the PCM properties were selected. The effect of thermal and moisture factors on the physical and mechanical properties of PCMs was studied. The studies have shown the positive effect of additional heat treatment of PCM on its properties. The microhardness of the matrix in the samples was investigated before and after heat treatment.

Постановка задачи: проблема обеспечения электромагнитной совместимости (ЭМС) современных радиоэлектронных средств (РЭС) все больше актуализируется с каждым годом. Причиной этому служит растущая функциональная сложность РЭС и тенденция к их миниатюризации, в т.ч. за счет увеличения плотности монтажа трассировки печатных плат (ПП). Электромагнитные помехи (ЭМП) различной природы способны привести к дестабилизации и разрушению элементов критичных РЭС. Под ними понимаются такие РЭС, выход из строя которых влечет за собой различные негативные последствия. Одним из видов ЭМП искусственной природы, отличающихся высоким напряжением, малой длительностью и широким спектром, являются сверхкороткие импульсы (СКИ). Последняя декада отмечена активным исследованием защитных структур с модальными явлениями для защиты критичных РЭС от СКИ, отличающихся рядом достоинств по сравнению с традиционными защитными устройствами. Принцип действия таких структур заключается в разложении СКИ на последовательность импульсов меньшей амплитуды из-за различия задержек мод в линии передачи. Их называют модальными фильтрами (МФ) и реализуют как в полосковом, так и в кабельном исполнениях. При проектировании МФ, одним из важнейших этапов является оптимизация, возможности которой, применительно к МФ, в настоящее время исследованы недостаточно. Кроме этого, без должного внимания остается вопрос функционирования МФ в экстремальных условиях. В частности, целесообразна оценка защитных характеристик МФ (ослабления СКИ, разности погонных задержек мод и др.) при воздействии температуры и влаги. Наконец, представляется важным определение оптимальных значений геометрических параметров МФ в экстремальных условиях и оценка возможности сохранения требуемых защитных характеристик. Целью работы является исследование защитных характеристик МФ на основе 3-проводной микрополосковой линии (МПЛ) при влиянии температуры и влаги при однои двухкритериальной оптимизации. Используемые методы: при вычислениях использована система квазистатического моделирования, основанная на методе моментов, а при оптимизации использовались простой генетический алгоритм (ГА) и модифицированный алгоритм эволюционных стратегий (ЭС). Оптимизация выполнялась по амплитудному критерию и критерию согласования. Моделирование влияния температуры выполнено с учетом известной модели вида P(T) с учетом термического изменения геометрических и электрофизических параметров МПЛ. Новизна: впервые выполнена однои двухкритериальная оптимизация с использованием ГА и модифицированного алгоритма ЭС МФ на основе 3-проводной МПЛ при влиянии температуры и влаги. Достигнута высокая сходимость результатов при оптимизации: отклонение максимального значения напряжения на выходе МФ не превышает 1% при использовании температурной модели и 6% при исследовании влияния влаги. В результате двухкритериальной оптимизации получены равные амплитуды импульсов разложения на выходе МФ при согласовании МФ с трактом. Установлено, что наименьшее значение максимального напряжения на выходе МФ достижимо при более низкой температуре окружающей среды. Продемонстрирован рост результирующего значения максимального напряжения на выходе при моделировании МФ с учетом конденсата. Результат: в результате двухкритериальной оптимизации удалось получить равные амплитуды импульсов разложения на выходе МФ при его согласовании с трактом. Таким образом, продемонстрирована возможность обеспечения высоких защитных характеристик МФ на основе 3-проводной МПЛ в экстремальных условиях. Практическая значимость: выявленные особенности поведения защитных характеристик МФ при воздействии температуры и влаги, а также их высокий уровень при функционировании в подобных средах, открывают возможность детализации и оценки параметрических и электрофизических параметров ПП, в т.ч. за счет оптимизации, с учетом воздействий окружающей среды еще на этапе проектирования ПП. Наконец, открывается возможность практического применения исследуемого МФ для защиты РЭС от СКИ (ввиду малой массы, радиационной стойкости, надежности и улучшенных характеристик) в самых различных сферах, в т.ч. в экстремальных условиях., Problem statement: the problem of ensuring electromagnetic compatibility (EMC) of modern radio-electronic equipment (REE) is becoming more and more relevant every year. The reason for this is the growing functional complexity of REE and the tendency to their miniaturization, including by increasing the density of printed circuit board (PCB) routing. Electromagnetic interference (EMI) of various natures can lead to destabilization and destruction of critical REE elements. Critical are understood as such REE, the failure of which entails various negative consequences. Ultrashort pulses (USP) are one of the types of EMI of artificial nature and are characterized by high voltage, short duration and wide spectrum. The last decade is characterized by active research of protective structures with modal phenomena for the protection of critical REE from USP, which differ in a number of advantages compared to traditional protective devices. The principle of operation of such structures is to decompose the USP into a sequence of pulses of smaller amplitude due to the difference in mode delays in the transmission line. They are called modal filters (MF) and are implemented in strip and cable versions. One of the most important stages when designing an MF is optimization. Opportunities for optimization, in relation to the MF, are currently not studied enough. In addition, the issue of the MF operating in extreme conditions remains without due attention. In particular, it is expedient to evaluate the protective characteristics of the MF (USP attenuation, the difference in per-unit-length mode delays, etc.) when exposed to temperature and moisture. Finally, it seems important to determine the optimal values of the geometric parameters of the MF under extreme conditions and assess the possibility of maintaining the required protective characteristics. The purpose of this work is to study the protective characteristics of an MF based on a 3-conductor microstrip line (MSL) when exposed to temperature and moisture in singleand multicriteria optimization. Methods used: in calculations, we used a quasi-static simulating system based on the method of moments, and in optimization we used a simple genetic algorithm (GA) and a modified algorithm of evolutionary strategies (ES). We performed optimization according to the amplitude the matching criteria. We simulated the temperature exposure taking into account the well-known model of the P(T) type, taking into account the thermal change in the geometric and electrical MSL parameters. Novelty: for the first time, singleand multicriteria optimization of the MF based on a 3-conductor MSL was performed using GA and a modified ES algorithm when exposed to temperature and moisture. We managed to achieve high convergence of results during optimization: the deviation of the maximum voltage at the MF output does not exceed 1% when using the temperature model and 6% when exposed to moisture. As a result of multicriteria optimization, we obtained equal amplitudes of decomposition pulses at the MF output when matching the MF with the path. We have found that the lowest maximum voltage at the MF output is achievable at lower ambient temperatures. The resulting value of the maximum voltage at the MF output increases when MF is simulated with condensate on its surface. Results. As a result of multicriteria optimization, we managed to obtain equal amplitudes of decomposition pulses at the output of the MF when its matching with the path. Thus, the article demonstrates the possibility of providing high protective characteristics of an MF based on a 3-conductor MSL under extreme conditions. Practical relevance. The identified features of the behavior of the protective characteristics of the MF when exposed to temperature and moisture, as well as their high level when functioning in such environments, open up the possibility of detailing and evaluating the parametric and electrophysical parameters of the PCB, including through optimization, taking into account environmental exposures at the PCB design stage. Finally, the possibility of practical application of the investigated MF for the protection of REE from USP (due to its low mass, radiation resistance, reliability, and improved characteristics) opens up in a wide variety of areas, including under extreme conditions.

Searching less toxic materials with both ideal bandgaps (1.0–1.5 eV for single-junction solar cells) and excellent stability remains a big challenge in perovskite optoelectronic materials field. Here, we report the optoelectronic properties and stability of the [H3NC6H4NH3]CuBr4 perovskite material. Intriguingly, the material features a bandgap of 1.43 eV which approaches that of GaAs (1.42 eV)—the state of the art semiconductor for single-junction solar cells. Furthermore, the [H3NC6H4NH3]CuBr4 film shows excellent stability, and can tolerate continuous moisture exposure for 1200 h in air (relative humidity: 40–50%) and ultraviolet light exposure for 1008 h in a glove box filled with nitrogen. Finally, we successfully realized a pinhole-free, smooth, and large-area (>20 cm2) [H3NC6H4NH3]CuBr4 film—the largest Cu-based perovskite film ever reported—via a hot-casting technique. Owing to its ideal bandgap and excellent stability, [H3NC6H4NH3]CuBr4 can be considered as a milestone in the development of low bandgap, highly stable, and lead-free perovskite materials for potential optoelectronic applications.

Clarification of how water affects the photovoltaic performance of perovskite solar cells is one of the major challenges to successfully develop a large-scale low-cost fabrication process. Many authors have reported beneficial effects of moisture during the fabrication of perovskite solar cells (PSCs), such as enhanced crystallinity, photoluminescence and photovoltage. However, the highest power conversion efficiency reported until this date was obtained under completely dry atmosphere conditions, avoiding the presence of water during perovskite formulation and preserving the damage caused by moisture exposure with encapsulation techniques. This apparent contradiction makes patent the necessity of an extensive clarification to establish the conditions in which water represents a beneficial or harmful factor in the development of high efficiency and stable perovskite devices. In this review, we summarized the effects of water, both as an additive into the perovskite formulation as an additive and as moisture exposure during fabrication. We discuss in depth the structural and chemical effects, analysing also the photovoltaic consequences during operation conditions. As a final input, we remark a useful method to perform high efficiency PSCs under different lab ambient conditions and highlight the latest advances in hydrophobic devices and encapsulation techniques.

Understanding why wood bonds fail is an excellent route toward understanding how to make them better. Certifying a bonded product usually requires achieving a specific load, percent wood failure, and an ability to withstand some form of moisture exposure without excessive delamination. While these tests protect the public from catastrophic failures, they are not very helpful in understanding why bonds fail. Understanding failure often requires going beyond what meets the naked eye, conducting additional tests, probing the wood surface, the fracture surface, adhesive properties, and the interaction of wood and adhesive during bond formation and service. This review of wood bond analysis methods reviews fundamentals of wood bonding and highlights recent developments in the analyses and understanding of wood bonds. It concludes with a series of challenges facing the wood bonding community.

A Pennisetum purpureum/glass-reinforced epoxy (PGRE) hybrid composites was comprehensively characterised to assess its impact response behaviour at room temperature (RT), under moisture exposure, and elevated temperatures. The untreated, 5 and 10% alkali-treated PGRE composites were fabricated using hybridised Pennisetum purpureum/woven E-glass fibres and epoxy resin. An instrumented IMATEK IM10 drop weight impact tester was utilised to characterise the impact responses of the prepared hybrid composites. The specimens were subjected to water exposure for 50, 100, 200, and 400 h and before arranged with a low-velocity impact test. In addition, the tests were repeated at 40, 60, and 80 °C to examine the effects of elevated temperatures. The results indicate that the untreated PGRE composite yielded the highest peak load impact response at all energy levels. The stiffness of the composites found to decrease substantially with increasing temperatures, which increases the absorbed energy and peak deflection causing extensive damage to the specimens.

This paper aims to investigate the spatially non-uniform frost damage process in RC beams during large numbers of freeze/thaw cycles (FTC). The material-based thermodynamic and poromechanical frost damage models have been up-scaled to the structural level considering the anisotropic stress-strain conditions and the condensed water movement in the crack system. The ice-induced pore pressures are also integrated in the smeared RC element in consideration of the path-dependent nonlinear constitutive laws. The frost damage accumulation processes (referred as the expansive strain) are simulated with different depths of heat and moisture exposure, as well as various arrangements of reinforcing bars. Based on the proposed empirical model which links the expansive strain with the reduction in ultrasonic velocity, the 3D frost damage profiles are compared with 2D ultrasonic velocity data, which show a satisfactory agreement. Finally, the effects of different steel and structural confinements on the frost damage profile are numerically investigated and discussed in detail.

Healthy hair structure is important to avoid hair loss or hair damage. Excessive exposure to pH, moisture and temperature can cause many changes in original hair structure. The objectives of this study were; 1) to determine the effects of extreme temperature, pH and moisture on human hair, 2) to observe the characteristics of healthy hair include smoothness, colour and shine. In this study, hair samples were sampled from a female student. Then, the samples were tested with three variables which were temperature (extreme cold and high temperature), pH (extreme acid and base) and moisture (coconut oil). The observations were recorded in five days and two times (8:00 a.m and 4:00 p.m) daily. All hair samples were observed under dissecting microscope to study the variable of healthy hair based on smoothness, colour, and shine. The hair samples that exposed to excess amount of virgin coconut oil, high temperature (100 °C) and acidic condition (pH 3) were damaged while pH between 5 to7 was found to be the perfect range to be used on hair. Hair is considered healthy when the hair is smooth with no frizz or any braided hair. The colour of hair must be no different from its original colour. Hair shine means that the hair look shiny when exposed to light. The results can provide useful baseline information for cosmetic company to assist in production of hair care products in the future.

Разработка новых технико-криминалистических средств выявления и фиксации следов рук на протяжении последних десятилетий ведется «на стыке» различных отраслей знаний, и до настоящего времени данное направление остается актуальным и востребованным. Значительный интерес, с практической точки зрения, представляют материалы, позволяющие работать со следами рук, подвергшимися воздействию влаги. В большинстве случаев подобные вещества представлены в виде стабилизированных высокодисперсных коллоидных систем, в которых в зависимости от цветовых характеристик следовоспринимающих поверхностей подбирается состав дисперсной фазы. В представленной работе на основе теоретических, информационных и экспериментальных данных описан процесс взаимодействия в трехфазной системе: дисперсная система – потожировое вещество – поверхность объекта-следоносителя. На основе патентов-аналогов, выбранных в результате патентного поиска, авторами разработанысоставы дисперсной системы на основе дисульфида молибдена для выявления следов рук, подвергшихся воздействию влаги. Проведены многочисленные эксперименты. Для иллюстрации качественных возможностей разработанных составов приведены примеры изображений следов рук, выявленных одним из составов дисперсной системы на различных видах поверхностей следо­носителей., Development of new forensic equipment to detect and fix hand prints has been carrying out since recent decades "at the interface of" diverse branches of knowledge and up to the present moment this field remains relevant and much needed. Materials that allow handling the hand prints exposed to moisture are of considerable interest from a practical perspective. In most cases such substances are represented in form of stabilized highly dispersive colloid systems where dispersion phase composition is designed depending on color specifications of surfaces where prints will be left. Based on theoretical, information and testing data the interaction process is described with regard to the three-phase system Disperse System – Sweat and fat substances – Surface of print carrier herein. Based on corresponding patents selected as a consequence of patent searches authors have developed molybdenum disulphide based disperse system compositions to detect hand prints exposed to moisture. Numerous experiments were conducted. In order to demonstrate qualitative feasibilities of deve­loped compositions some examples of hand prints detected by one of disperse system composition on print carriers' surfaces of all kinds are provided., Судебная экспертиза, Выпуск 3 (67) 2021, Pages 104-115

Exposure of the fruit surface to moisture during early development is causal in russeting of apple (Malus &times, domestica Borkh.). Moisture exposure results in formation of microcracks and decreased cuticle thickness. Periderm differentiation begins in the hypodermis, but only after discontinuation of moisture exposure. Expressions of selected genes involved in cutin, wax and suberin synthesis were quantified, as were the wax, cutin and suberin compositions. Experiments were conducted in two phases. In Phase I (31 days after full bloom) the fruit surface was exposed to moisture for 6 or 12 d. Phase II was after moisture exposure had been discontinued. Unexposed areas on the same fruit served as unexposed controls. During Phase I, cutin and wax synthesis genes were down-regulated only in the moisture-exposed patches. During Phase II, suberin synthesis genes were up-regulated only in the moisture-exposed patches. The expressions of cutin and wax genes in the moisture-exposed patches increased slightly during Phase II, but the levels of expression were much lower than in the control patches. Amounts and compositions of cutin, wax and suberin were consistent with the gene expressions. Thus, moisture-induced russet is a two-step process: moisture exposure reduces cutin and wax synthesis, moisture removal triggers suberin synthesis.

Expanded polystyrene (EPS) and extruded polystyrene (XPS) are common insulation materials used in thermal insulation systems for below-grade applications. Moisture control components in these systems sometimes fail, resulting in moisture exposure to the surrounding insulation. Although there are several laboratory methods proposed in the literature on the determination of moisture content in polystyrene insulation, the correlations between laboratory data and field data are not evaluated in detail. This paper first conducted an analysis on such correlations and provided a comparison on the laboratory methods defined in different standards. Based on the findings on the correlation study, the criteria on the moisture behavior of polystyrene insulation setting in two main building codes (ASHRAE 90.1 and ASCE 32) that utilize the laboratory data and specific test standards were discussed in detail. Recommendations on the test methods that can better correlate the laboratory data with long-term performance were also present in this paper and these improvements would be able to provide more appropriate information to the building codes.

This paper reports on the study of flexible epoxy resin which lowers modulus to minimize warpage while maintaining high filler content. Liquid Compression Molding (LCM) material is an encapsulation material applied at the wafer level. LCM requires high reliability and minimized warpage after curing. The flexible epoxy resin was studied to determine if it could be technically feasible to meet the requirements. Three epoxy resins with different structures, Conventional epoxy, and Flexible epoxy A and B, were examined. Both samples with Flexible epoxy A and B resulted in lower warpage than Conventional resin. Especially, Flexible epoxy B showed the minimal warpage with the lowest modulus. The sample with Epoxy B performs the best at 260 degree Celsius with the minimal warpage. A reliability test of LCM with Epoxy B was also conducted assuming the application for Fan-out packaging. Epoxy B showed no delamination or cracks under a thermal cycling test up to 1,000 cycles after MSL1 moisture exposure.

The development and multiaxial distribution of mechanical expansions caused by alkali-silica reaction were quantified for a large-scale reinforced concrete beam containing top and bottom mats of bidirectional reinforcement with no reinforcement through its depth. The effects of different conditioning environments and the influence of reinforcing bar size and layout on the expansion behavior of the beam were also considered. Expansions in the unreinforced direction exceeded those in the reinforced directions at all times. Expansions in the reinforced directions stopped prior to steel yielding and before concrete finished expanding in the unreinforced direction. Expansion behavior in biaxially reinforced beam regions was not influenced by triaxial restraint conditions at adjacent beam ends. Varying moisture exposure conditions along the length affected the time development of expansions but not the distribution of given volumetric expansions among primary directions.

Syntactic foams are commonly fabricated with sodalime–borosilicate glass hollow microsphere fillers, which are susceptible to degradation after long-term or high temperature moisture exposure. In comparison, borosilicate glass hollow particles offer higher degradation resistance to moisture, lower thermal expansion, and higher softening temperature. This work explores borosilicate glass hollow microspheres for use as fillers in syntactic foams and studies their thermophysical properties. The coefficient of thermal expansion over the temperature range 35–90℃ was observed to decrease from 62.4 μ/K for the matrix resin to a minimum of 24.3 μ/K for syntactic foams, representing higher thermophysical stability of syntactic foams. Theoretical models are used to conduct parametric studies and understand the correlation between material parameters and coefficient of thermal expansion of syntactic foams. The dynamic mechanical analysis results show that the storage modulus of syntactic foams increases with increasing glass hollow microsphere wall thickness and with decreasing glass hollow microsphere volume fraction in the glassy region at 40℃. The β-relaxation of the matrix resin found at 66.1 ± 2.0℃ was suppressed in the majority of syntactic foams, further improving the stability around typical application temperatures.

Compression after impact behaviour of Glass/Vinylester composite laminates, which have been subjected to water exposure for a long period of over 20 months, is studied. Furthermore, tests are carried out for three different specimen thicknesses aged in three different water types; potable, salted and sea water. The results of these tests are compared with those of non-impacted specimens to determine the change of the residual strength at different impact energies. The results show the load-displacement and load-strain curves of compression after impact tests. Moreover, the changes of residual compressive strength are determined with respect to the various imposed impact energy for different thicknesses. Failure modes and impact response of dry and wet specimens are discussed.

The penetration of atmospheric water (rain) into facades creates problems for building habitability and the durability of construction materials. This study analyses the exposure of Brazilian facades to the two main climate factors responsible for this penetration: wind-driven rain and driving rain wind pressure. Daily weather records (spanning 2005–14, from 171 weather stations) were analysed. Both exposure factors were combined to assess the risk of water penetration at each site. The relationships between the different exposure indices calculated from daily, monthly and annual records were determined and compared with results from other countries. From this analysis, detailed isopleth maps are provided that allow a graphical characterization of the moisture exposure conditions of facades anywhere in Brazil. A comprehensive characterization of the water penetration exposure in Brazilian enclosures is created and can be used to establish normative design requirements for actual climatic condition...

This paper presents a research focused on an e-textile based warning system for firefighters which is intended to bring more safety to firefighters on-the-job. The system is designed so that it is integrated into an undergarment shirt worn underneath a firefighter's protective jacket/suit. It is able to monitor heart rate, detect a firefighter's position relative to his posture, detect CO gas concentrations in the environment and measure ambient temperature. The warning system, as a whole, consists of the sensors and a microcontroller integrated into the undergarment through e-textile technology, and a wireless monitoring device. Measured data are wirelessly transmitted and received by the monitoring device capable of data visualization and are intended to be used by an operation chief to monitor a firefighter. When monitored data exceed a certain threshold value the firefighter will be notified by means of a light and sound alarm. The system performed well when tested against specific digital sensors and withstood moisture exposure tests. Wireless communication was consistently established to the monitoring device.

Cable ampacity analysis is generally performed assuming constant worst-state environmental conditions, which often correspond to a dry soil condition or to a condition with uniform ambient soil moisture content. The characteristic time scale of thermal variation in the soil is large, on the order of several weeks, and is similar to the time scale between rainfall events in many geographic locations. Intermittent rainfall events introduce significant transient fluctuations that influence the thermal conditions and moisture content around a buried cable both by increasing thermal conductivity of the soil and by increasing the moisture exposure of the cable insulation. This paper reports on a computational study of the effect of rainfall events on the thermal and moisture transients surrounding a buried cable. The computations were performed with a finite-difference method using an overset grid approach, with an inner polar grid surrounding the cable and an outer Cartesian grid. The thermal and moisture transients observed in computations with periodic rainfall events were compared to control computations with a steady uniform rainfall. Under periodic rainfall conditions, the temperature and moisture fields are observed to approach a limit-cycle condition in which the cable surface temperature and moisture content oscillate in time, but with mean values that are significantly different than the steady-state values.

Environmental related durability issues have been of great concerns in the structures strengthened with the fiber reinforced polymers (FRPs). In marine environment, moisture is one of the dominant factors that adversely affect the material properties and the bond interfaces. Several short-term and long-term laboratory experimental investigations have been conducted to study such behaviors but, still, there are insufficient constitutive bond models which could incorporate moisture exposure conditions. This paper proposed a very simple approach in determining the nonlinear bond-slip models for the FRP-concrete interface considering the effect of moisture conditions. The proposed models are based on the strain results of the experimental investigation conducted by the authors using 6 different commercial FRP systems exposed to the moisture conditions for the maximum period of 18 months. The exposure effect in the moisture conditions seems to have great dependency on the FRP system. Based on the contrasting differences in the results under moisture conditions, separate bond-slip models have been proposed for the wet-layup FRP and prefabricated FRP systems. As for the verification of the proposed model under moisture conditions, predicted pull-out load was compared with the experimental pull-out load. The results showed good agreement for all the FRP systems under investigation.

Effect of environmental conditioning on scratch performance of polymethylmathacrylate (PMMA) is investigated. Three different grades of PMMA with varying levels of polarity were chosen and their scratch resistance compared in both dry and moist conditions. Linear increasing normal load scratch tests were performed according to ASTM D7027/ISO 19252 standards. Results indicate a drop in scratch resistance with initial exposure to moisture in all three systems. In the two highly polar PMMA systems, the scratch resistance recovers to that of the dry condition after long exposure to moisture. It is proposed that the moisture absorbed initially acts as a plasticizer causing weakening of the surface mechanical integrity. In the case of more polar systems this moisture absorption continues until saturation where water molecules cluster and impart a degree of lubrication and consequently improves scratch resistance.

There are currently no standards regulating water management for mass timber elements during construction, little knowledge of impacts of moisture exposure (wetting and drying performance, dimensional stability, checking), and few precedents serving as guidelines for monitoring moisture response of mass timber. To address these gaps, a hygrothermal monitoring study was devised to track moisture performance of U.S. made cross laminated timber (CLT) and glulam at a three-story mass timber building. This paper discusses moisture measurements that were collected during the first six months of construction at a CLT rocking shear wall and a timber floor connection. Despite the limited number of structural systems monitored during construction, the distribution and number of sensors in these elements allow to draw some important conclusions. The data confirmed that moisture distribution and wetting/drying rates varied based on local conditions and details (aspect, coatings, connections, etc.), with measurements at an uncoated, north-facing area showing the highest moisture levels (reaching fiber saturation at multiple ply depths and locations). Most locations rarely exceeded 16% moisture content for more than a few months. Certain moisture-trapping details consistently showed higher moisture levels (i.e., above 16%) and poorer drying. Some interior plies continued to show slow increases in MC even after months of drying conditions. These observations suggest preventative approaches implementable in the design (e.g., avoiding moisture trapping details), during fabrication (e.g., localized coating), and construction (e.g., sequencing installation to minimize exposure and allow drying).

When adhesively bonded joints are exposed to a moist environment, the tensile load capability of the joint is significantly decreased because moisture absorption weakens the mechanical properties of epoxy adhesive. In this paper, a nanoclay with excellent penetration resistance properties was used as a filler in epoxy adhesive in order to enhance adhesive strength in moist environments. The water absorption of the epoxy adhesive and the adhesive strength of the adhesively bonded joints were measured in water absorption experiments with respect to the weight fraction of the nanoclay and the moisture exposure time. These results showed that the tensile load capability of the nanoclay-filled adhesively bonded joint was greatly enhanced, even in a moist environment, because the nanoclay reduced water absorption into the epoxy adhesive as well as into the interface between the epoxy adhesive and the steel adherend and increased the strength of the epoxy adhesive itself.

Purpose – The authors aimed to develop environmentally stable NIR‐absorbing windows by blending a near‐infrared (NIR)‐absorbing dye and a photo‐crosslinkable polymer.Design/methodology/approach – To prepare an environmentally stable NIR‐absorbing window, a NIR‐absorbing dye was mixed with crosslinkable poly(vinyl cinnamate) (PVCn). The crosslinking of PVCn was carried out by photo‐dimerisation reaction of cinnamate with UV‐exposure at a wavelength of 254 nm for 4 min.Findings – The resistance of the photo‐crosslinked hybrid films against humidity, heat, and ultraviolet radiation damage was improved dramatically relative to the pristine NIR‐absorbing dye. These improvements result from the protection of NIR‐absorbing dye to moisture exposure in the presence of the polymer network.Originality/value – The simple and practical method resulted in a dramatic improvement in the environmental stability of NIR‐absorbing window.

Long-term moisture exposure has been shown to affect the mechanical performance of polymeric composite structures. This reduction in mechanical performance must be considered during product design in order to ensure long-term structure survival. In order to determine the long-term moisture effects on composite components, representative parts are commonly tested after having been exposed to an accelerated moisture conditioning environment. Accelerated moisture conditions are established in order to rapidly drive moisture into test specimens simulating worst-case long-term exposure scenarios. Currently, accepted methodologies for analyzing the time required to condition specimens are limited, allowing only simple geometry and an assumption that diffusivity rates are independent of the flow path or direction. Therefore, a more advanced finite element method is desired. In this study, a three-dimensional model is developed and implemented in commercial finite element code. The parametric study has been conducted for three-dimensional shapes, moisture diffusion pathways, and varying moisture and temperature conditions. Finite element results are validated with a one-dimensional analytical model and experimental results. A user-subroutine was implemented in commercial finite element code to calculate the moisture content. The ultimate goal for this research is to determine the exposure time for accelerated conditioning that produces the most accurate moisture distribution with the part and minimize over-conditioning of the laminate.

Background: Robustness of inhaler performance is required for successful asthma and COPD management. Easyhaler ® (EH) is a multi-dose dry powder inhaler which is used to deliver a wide range of various medications, the latest being budesonide-formoterol combination product (BF EH). Methods: The aim was to determine the delivered dose (DD) uniformity and fine particle dose (FPD) of BF EH 80/4.5, 160/4.5 and 320/9 µg/inhalation, as a function of dosing interval. DD and FPD analyses were done using the flow rate corresponding to a 4 kPa pressure drop across the inhaler (Ph. Eur. method). The effect of environmental moisture on the DD and FPD was examined. DD was analysed from the first five doses. After the fifth dose the inhalers without aluminium laminate pouch were placed in the 30oC/75% RH storage condition for 48 hours. After the storage the next five doses were analysed. The amount of doses in FPD analyse was ten. Additonally, dropping, vibration and freeze-thaw tests were performed. Figure 1. BF EH Delivered dose (%) after elevated temperature and moisture exposure Conclusions: BF EH delivers consistently accurate doses throughout inhaler life. Consistency of overall dosing was maintained under exposure of BF EH to variations in temperature and humidity as well as after dropping, vibration and freeze-thaw tests.

Package-on-Package (PoP) technology is widely used in mobile devices due to its simple design, lower cost and faster time to market. Warpage characteristic and requirement of PoP package becomes critical to ensure both the top and bottom package can be mounted with minimal yield lost. With this challenge in placed, iNEMI has been working relentlessly to fingerprint the current PoP package technology warpage characteristic and to establish some key learning for packaging technologies. The work also extended to understand the basic requirement needed for successful PoP stacking by analyzing the warpage data obtained and formulate a simple analytical equation to explain the true warpage requirement for PoP packaging. The warpage characterization also extended to evaluate the effect of bake and Moisture Exposure Time (MET) on package dynamic warpage. These will provide a better holistic view of cause and effect in PoP package stacking.

In this work we examine the effect of storage conditions (moisture exposure) on the compression behavior of 2 grades of spray-dried lactose (Pharmatose DCL 11 and Pharmatose DCL 14) under 2 different circumstances. The first was to expose powder samples to moisture, then compress them. The second was to expose precompressed tablets to moisture. We clearly show that the effect of moisture exposure and amorphous content crystallization in spray-dried lactoses on compaction behavior depends on whether this moisture exposure takes place before or after compression. In addition, the impact of storage conditions depends on the grade of spray-dried lactose.

This paper presents a methodology with the purpose of modeling and simulating outdoor temperature and relative humidity (vapor concentration) related to moisture exposure on timber structures. The methodology is based on time-series analysis with recorded meteorological data used as input. In situations where recorded data is missing or consists of limited sequences, this methodology offers the possibility to use synthetic data instead. It was found that temperature and vapor concentration could be modeled by a combination of deterministic functions and stochastic processes, which consider the dynamics of the climate, including slow seasonal variations and fast daily changes. Specifically, a model for temperature and vapor concentration in Stockholm, Sweden, is presented together with simulation results. It is shown that the model produces simulated sequences with statistical properties close to the real recorded ones.