Air Blast Research Articles

Evaluation of Three Methods for the Treatment of Dentin Hypersensitivity: A Randomised Clinical Trial

ObjectivesIn this study, we aimed to compare the effectiveness of Gluma and high-power 980-nm diode laser, alone or in combination, in the treatment of cervical dentin hypersensitivity. MethodsA total of 20 patients (5 men and 15 women), aged 25 to 60 years, who met the inclusion criteria, were enrolled in this study. A total of 60 teeth were randomly divided into 4 groups: G1, 980 nm diode laser (in 2 sessions within a 1-week interval); G2, Gluma (in 2 sessions within a 1-week interval); G3, 980 nm diode laser plus Gluma; and G4: control. Thermal (cold spray) and air blast (air syringe of dental unit) stimuli were used to evaluate cervical dentin hypersensitivity in the patients. Their pain response was assessed using a visual analogue scale (VAS) before treatment (baseline), in the first treatment session (15 minutes after treatment), in the second treatment session (after 1 week), and in 2-week, 1-month, and 3-month follow-up sessions. The obtained data were analysed using non-parametric tests, including Kruskal–Wallis test, Friedman test, Mann–Whitney test, and Wilcoxon test, in SPSS Version 22 at a significance level of P < .05. ResultsBased on the results, there was a significant difference in the average VAS scores for cold and air blast stimuli between the 4 groups 1 month after the intervention (P < .05). Meanwhile, the laser group had the lowest VAS score for cold and air stimuli. On the contrary, no significant difference was found between the 4 groups 3 months after the intervention (P ˃ .05). ConclusionThe present results showed that 980-nm diode laser alone was more effective than the other 2 intervention methods for 1 month. Trial registrationThe study was registered in the Iranian Registry of Clinical Trials (IRCT20120901010703N5).

An Innovative Passive Noise Control Technique for Environmental Protection: An Experimental Study in Explosion Noise Attenuation

Passive noise control techniques are an effective way of mitigating environmental noise pollution caused by industrial activities, assisting with long-term sustainability in workplace health and safety. Excessive noise from various sources such as mining, construction, manufacturing, air blasting and large-scale gas and dust explosion investigations is challenging as it produces a high level of noise. Excessive explosion noise can have a significant impact on the surrounding environment and people. To suppress the noise to satisfactory levels for nearby occupants, several layers of acoustic barriers are employed. The effectiveness of each level of acoustic barrier is presented. A bottom ash granule base layer with a 300 mm thickness reduced the peak noise levels (136 dBA) by approximately 33 dBA. In the next stage, an autoclaved aerated concrete (AAC)-based 200 mm acoustic barrier was introduced, which suppressed 24 dBA of noise. The inside of the AAC acoustic barrier was finally covered with a 50 mm thick noise attenuation composite material layer constituted of a sound barrier and a sound absorber, and this composite material attenuated the noise level by 6 dBA. The entire noise suppression mechanism was found to be an effective way to suppress gas and dust explosion noise and satisfy the requirement of the occupant and sound level.

Histopathological and ultrastructural changes in the rats brain after air shock wave impact

The using of explosive substances and devices can lead to brain injuries, the diagnosis of which requires the determination of primary biomarkers. Therefore, the aim was to establish and study histopathological and ultrastructural changes in the rats brain after exposure to an air blast wave. The study was carried out on 18 male Wistar rats, which were randomly divided into two groups: sham (n=9) and experimental (n=9). The animals of the experimental group were anesthetized with halothane and gently fixed in a horizontal position on the abdomen with the front part of the rat's muzzle at a distance of 5 cm from the device opening and subjected to an excess pressure of 26-36 kPa. Animals of both groups were decapitated, brains were removed, fixed, histopathological and ultrastructural analyzes were conducted using standard methods. Intergroup differences were assessed by Mann-Whitney U-test. Light microscopy revealed primary lesions in the form of small focal, multifocal hemorrhages, cerebral vessel ruptures and microscopic ruptures of the brain substance. In almost all brain samples, there is a significant saturation of the venous vessels with the presence of erythrocyte stasis. Violation of the blood-brain barrier, the presence of edema of the perivascular space, and petechial hemorrhages in the neuropil were registered ultrastructurally. Based on the study results, a morphological algorithm for assessing primary histostructural intracranial brain injuries and their consequences after exposure to an air shock wave was proposed. The injuries were found to be caused by the direct traumatic effect of the air shock wave. In the acute post-traumatic period, histopathological and ultrastructural changes in the brain can manifest as changes in neurons and in the blood-brain barrier and be accompanied by perivascular multifocal small-focal hemorrhages, neuropil ruptures, edema of pericellular and perivascular spaces, which together can be considered as biomarkers of primary traumatic changes after exposure to an air shock wave.

Design of Air Blast Freezing System Using Cascade Refrigeration R290/R32 System with Capacity 5kg

Indonesia is a maritime country that has an abundance of marine catches. In 2022, the production of marine catches reached 24.85 millions tons, while the export amount was 1.221 millions tons. This is due to the limited technology that can extend the freshness of marine catches. Based on this problem, a cooling system was designed in the form of an ABF that can freeze marine catch products. The Air Blast Freezing (ABF) system is designed at an air temperature of -40oC using a cascade refrigeration system. The working fluid used is R290/R32 hydrocarbon, which has very low GWP and ODP so it is safe for the environment and the earth's ozone layer. The results obtained show that the cooling load is 444.037 Watts, the LTC compressor power and HTC compressor power are 116.19 Watts and 205.98 watts. The designed air blast freezing system has a surface area of LTC evaporator of 2.670 m2 and HTC condenser of 4.780 m2. The calculated capillary pipe length is 1.94 m for HTC and 1.51 m for LTC, the COP of the ABF system is 2.774.

A Comparison of a Standard Radial Airflow and a Double Volute-Generated Focused Airflow Air Blast Sprayer to Control Scab in Tall Pecan Trees.

Pecan (Carya illinoinensis) is a valuable crop in the southern United States. Scab (caused by Venturia effusa) is a major biotic constraint to pecan production in the southeastern region and requires 10 to 15 or more fungicide applications for control. Spray application relies on large standard radial airflow air blast sprayers (SSs). Some SSs have been adapted to include a volute on one side to project spray higher into the canopy because of a decline in coverage with height. A grower-designed and engineered double volute-generated focused airflow air blast sprayer (DVS) was assessed for scab control and spray coverage compared with an SS. Over three seasons, on foliage and fruit, scab control was either equal to or superior using the DVS sprayer. On mature fruit, in 2017, scab severity on the control was 9.07%, on the DVS it was 0.19%, and on the SS it was 0.24%; in 2018 severity was 84.4, 18.4, and 29.1%, respectively; and in 2019 it was 32.7, 7.0, and 11.6%, respectively. There were no discernable gradients in scab severity with tree height with either sprayer in 2017, but in 2018 the difference was significant, with the DVS having a shallower gradient, and in 2019 the DVS slope was numerically less steep compared with the SS. Mature fruit weight was significantly greater on trees treated using the DVS compared with the SS in 2017 and 2018 but was not different in 2019. Spray coverage studies showed that the DVS sprayer had significantly more coverage at heights >13.8 m (up to 19.0 m), ranging from 18.4 to 14.1%, compared with coverage using the SS, which ranged from 7.9 to 2.9%. The slope in decline of spray coverage with height was significantly shallower with the DVS sprayer, and spray profiles reflected these differences. Disease control was improved overall when using the DVS, and the DVS provided greater spray coverage at heights >13.8 m when compared with the SS sprayer. The DVS design may offer economical, superior scab control in pecan orchards where trees are >13.8 m tall.

Performance investigation of highway bridge pier columns under the sequential effects of fire followed by vehicle collision and subsequent air blast: A numerical investigation

Historically, it has been demonstrated that bridges may be vulnerable to fire, and in many circumstances, resulting damage might not be apparent, and bridges could maintain acceptable levels of serviceability. In the absence of proven assessment tools and given the limited research that addresses bridge fire, research that better understands response and strives to improve highway bridge resiliency to fire is needed. Extending the work carried out during an earlier research stage, the present study focused on investigating performance of bridge pier columns that survive fire under coupled vehicle collision and air blast. Numerical models of single reinforced concrete columns supported by a pile foundation system and surrounded by air and soil volumes were created using LS-DYNA. As explicit solvers such as those available in LS-DYNA are infrequently used for fire analysis, an indirect two-step approach that integrated heat transfer and structural analyses was developed and validated against published fire-induced impact and blast test results. A parametric study that examined the effects of various fire exposure conditions and column diameters was completed. Performance was comprehensively assessed based on various structural response parameters, which included failure modes, lateral displacement, residual axial capacities, and shear demand-to-capacity ratios. Column damage was then categorized into six levels to qualitatively assess column performance under the aforementioned multi-hazards. The developed modeling approach was shown to be viable, and results indicated that larger column diameters could potentially remain in service in their final damage states after being repaired for fire durations of less than 120 min.

Effect of air blast freezing and frozen storage on inactivation of Vibrio vulnificus in Pacific oysters (Crassostrea gigas)

Air-blast freezing followed by frozen storage at different temperatures was assessed for inactivation of Vibrio vulnificus in Pacific oysters (Crassostrea gigas). Pacific oysters were allowed to bioaccumulate a cocktail of six strains of V. vulnificus. They were then air-blast frozen at −55 °C followed by frozen storage at −8 °C, −13 °C, −18 °C, −23 °C and −28 °C. V. vulnificus reductions were enumerated at different sampling times from 0 to 360 days. Air-blast freezing and frozen storage inactivated V. vulnificus in Pacific oysters in a two-phase inactivation pattern, with rapid inactivation during the first 3 days after air-blast freezing (short-term effect) followed by slower log-linear declines during frozen storage (long-term effect). The effects of storage temperature on V. vulnificus inactivation (log10 MPN/day) were assessed using a combined model that includes effects from both short- and long-term storage. The US National Shellfish Sanitation Program requires that postharvest processes to reduce Vibrio concentrations achieve ≥3.52 log reductions. At −18 °C this was achieved after an average of 90 days, but 95% confidence was not achieved until 123 days. Lower frozen storage temperatures caused slower declines of V. vulnificus. As well as artificially bioaccumulated V. vulnificus, we modeled inactivation of naturally occurring V. parahaemolyticus and showed that the results of a previous North American study fitted with our data. Their validated treatment for this organism in half-shell oysters can therefore be applied to New Zealand whole-shell oysters. This study will help guide oyster producers/processors aiming to achieve significant inactivation of Vibrio bacteria in their product, by providing a starting point for developing suitable frozen storage time/temperature conditions for Vibrio inactivation.

Numerical Analysis on the Dynamic Response of PVC Foam/Polyurea Composite Sandwich Panels under the Close Air Blast Loading.

This paper explores a novel structure aimed at enhancing its blast resistance performance by adding a layer of polyurea coating to the steel-PVC foam-steel sandwich panel. The response of 13 different arrangements of sandwich panels under explosive loading was studied using numerical simulation. The response process can be divided into three deformation stages: (1) Fluid-structure interaction; (2) Compression of the sandwich panel; (3) Dynamic structural response. The dynamic responses of the various sandwich panels to close-range air blast loading were analyzed based on the deformation characteristics, deflection, effective plastic strain, energy absorption, and pressure of the shock wave. The study draws the following conclusions: Reasonably adding a layer of polyurea to the traditional PVC foam sandwich panel can enhance its resistance to shock wave absorption, with a maximum increase of 29.8%; the optimal arrangement for explosion resistance is steel plate-PVC foam-polyurea-steel plate when the polyurea is coated on the back; and the best quality ratio between polyurea and PVC foam is 1:7 when the polyurea is coated on the front.

Rock avalanche-induced air blasts: Implications for landslide risk assessments

Rock avalanche-induced air blasts are widespread, damaging, and deadly. They can add to the destructive potential of avalanches far beyond the avalanche zone, but no landslide risk assessment in practice to date has accounted for the potential air blast danger. Here, field investigations and numerical studies were employed to quantitively analyze the initiation and propagation mechanism of air blasts triggered by the 2008 Wenjia Valley rock avalanche in Sichuan, China. Our findings indicate that the most significant air blast triggered by the Wenjia Valley avalanche was near bends in the valley, with a maximum pressure of over 25 kPa and a maximum velocity of 73 m/s. The avalanche violently collided with the valley wall at bends, generating multiple destructive air blasts and avalanche deflection. Subsequently, the separated air blast propagated as inertia flows and caused huge forest destruction. A systematic parametric study combined with case studies was further performed to investigate the possible contribution of topography and sliding mass properties to the air blast power. Large avalanche volume and high velocity both appear to be necessary conditions to generate a destructive air blast, while the sudden topography change is also greatly influential. Our work provides new insights into the initiation and propagation of rock avalanche-induced air blasts, compelling to consider this sort of cascading effect during landslide risk assessment in mountainous regions.

Ozone and Laser Effects on Dentin Hypersensitivity Treatment: A Randomized Clinical Study

IntroductionThe aim of this study was to evaluate and compare the clinical efficacy of diode laser and ozone gas in the treatment of dentin hypersensitivity (DHS). MethodsOne hundred thirty-two teeth from 44 patients with moderate DHS were randomized into 3 groups according to a split-mouth design. In the diode laser group, the operator irradiated the superficial dentin exposed with an 808-nm wavelength and incremental power from 0.2 to 0.6 W with a 20-second interval. In the ozone gas group, the operator applied a high dose of ozone (32 g/m3) for 30 seconds using a silicon cup. In the placebo group, no therapy was applied. The dentin sensitivity level was evaluated upon enrollment (T0), immediately after treatment (T1), 3 months post-treatment (T2), and 6 months post-treatment (T3) with a cold air blast challenge and tactile stimuli. The pain severity was quantified according to the visual analogue scale. The Wilcoxon signed rank test was used to scrutinize potential statistical disparities among the treatments. Statistical significance was predetermined at P < .05. ResultsA significant decrease of DHS was observed in the ozone gas group and the `diode laser group immediately after treatment and after 3 and 6 months of the therapy. After 6 months from the therapy, the sensitivity values in the teeth treated with ozone gas remained statistically lower than those treated with diode lasers (P < .05). ConclusionsA laser diode and ozone gas are both efficient as dentin sensitivity treatment. Ozone maintains an invariable effectiveness after 6 months.

Multifunctional composite structures with embedded conductive yarns for shock load monitoring and failure detection

This study evaluates the performance of composite structures with embedded conductive yarns during shock loads to create a multifunctional system for immediate failure detection. The scalable sensing yarns were made by braiding Kevlar fibers with Nitinol fibers and then integrating them into a carbon/epoxy prepreg. The multifunctional structure was subjected to a Mach 2 air blast load using a shock tube apparatus. The embedded sensor yarns were used to record their electrical performance, while Digital Image Correlation captured full-field displacements, velocities, and strains. In addition, pressure transducers measured shock event pressures. The results revealed that through-thickness failure of the laminated composite occurred at approximately 2.5% strain, which was visually observable. However, the embedded sensor exhibited out-of-range electrical measurements at around 1.5% strain, even though no visible structural damage was present. This demonstrates the embedded sensing yarns’ ability to detect delamination-type failures by responding to interlaminate damage, highlighting their advantages over conventional external sensors. Similarly, the gauge factor for the fiber system was determined to be 1.89 ± 0.07. This multifunctional system shows great potential for enhancing composite structure safety and performance in high-performance aerospace applications and offering real-time structural health assessment.

Reduction of Microplastic in Wastewater Via Electrocoagulation Process

In recent years, microplastic has become an emerging contaminant that has endangered the ecosystem and public health. This environmental issue has been discovered in the atmosphere, soil, and water bodies. These sources of pollutants can be either primary or secondary. The primary sources of microplastic are the clothing and cosmetic industry, plastic manufacturing plants, fishing businesses, shipping lines, sewage treatment plants, car tires and air blasting. Moreover, microplastic emission from secondary sources involves degrading large plastic particles to smaller elements under mechanical fragmentation and ultraviolet. Microplastic can be defined as plastic particles of different shapes that are less than 5mm. It can be denoted that this microplastic has been detected in the wastewater effluent and needs to be sufficiently removed from the conventional methods. Therefore, this research aims to determine the reduction rate of microplastic in wastewater via the electrocoagulation process. The wastewater effluent was taken from the wastewater treatment plant, Universiti Teknologi MARA Campus Dengkil. The characteristics of the wastewater effluent have been determined for biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia-nitrogen, total suspended solids (TSS), turbidity and E.coli. The microplastic employed in the experiment was polystyrene (PS). A duration of 60 and 120 minutes were taken to reduce the PS. Additionally, the analysis using Fourier-transform infrared spectroscopy (FTIR) has been done to observe the chemical structure of the PS polymer. The results showed that the maximum percentage of reduction for COD was 100%, TSS with a value of 80%, ammonia-nitrogen of 98% and turbidity of 46%. Besides, the removal of PS has achieved 82% using this technique. It can be found that electrocoagulation can be a promising method for reducing the microplastic in the water environment, especially in the wastewater treatment plant.

Reinforced Concrete Bridge Column Multihazard Performance: A Computational Tool to Assess Response to Vehicle Impact, Air Blast, and Fire

Reinforced Concrete Bridge Column Multihazard Performance: A Computational Tool to Assess Response to Vehicle Impact, Air Blast, and Fire

Deformation behavior of super-austenitic stainless steel sandwich panels subjected to air blast and underwater explosion

Super-austenitic stainless steel is a class of high alloy steels with enhanced toughness, outstanding strength, and corrosion resistance. In this article, the structural integrity of super-austenitic stainless steel square sandwich panels subjected to surface and underwater explosions is investigated through numerical simulations, and the results are validated with experiments. Abaqus Explicit Solver is used to predict the face deformation and core crushing failure modes of the sandwich panels. Simulations are performed for three levels of impulse load by varying the explosive quantity. The fluid-structure interaction is established by CONWEP and UNDEX algorithms for air blasts and underwater explosions respectively. The dynamic deformation behavior of the sandwich panel is modeled using the Johnson-Cook (JC) plasticity model incorporating strain rate and temperature effects. Good agreement is witnessed between the numerical predictions and experimental observations. An increment in deformation of the face sheet, cell wall buckling, and core compaction is observed with the increase in the impulse. From a series of air and underwater explosion simulations, the advantage of using sandwich structures for blast mitigation is demonstrated. In addition, the significance of numerical simulations to limit experiments and predict the deformation of the sandwich panels is presented.

Effect of Iontophoresis on the Effectiveness of Nano-Hydroxyapatite and Pro-argin in In-Office Treatment of Dentin Hypersensitivity: A Split-Mouth Randomized Clinical Trial.

Background and objectives Dentin hypersensitivity (DH) treatment is one of the main challenges dentists facein their daily clinical practice. Current therapies provide only temporary relief and require multiple applications to exhibit results, and there is a lack of evidence related to the long-term effects of these agents. Nano-hydroxyapatite (n-HA) and pro-argin (8.0% arginine-calcium carbonate) have recently been used fordentin desensitization with a one-time in-office application, but the effects are interim. However, a standard treatment protocol demandsdefinitive or enduring results. Since iontophoresis amplifiesthe transportof neutral and ionized drugsacross a membrane, the use of these desensitizing agents with iontophoresis may be beneficial to accomplish satisfactory results.This study was conducted to evaluate whether iontophoresis could enable better penetration of nano-hydroxyapatite and pro-argin into the dentin, enhancing and prolonging their therapeutic effect. Materials and methods Forty-five participants with dentin hypersensitivity in the age group of 20 to 60 years were included. In each individual, four teeth with cervical lesions (one from each quadrant) were selected and divided randomly into four groups: group I: desensitizing paste containing nano-hydroxyapatite, group II: desensitizing paste containing nano-hydroxyapatite with iontophoresis, group III: desensitizing paste containing pro-argin, and group IV: desensitizing paste containing pro-argin with iontophoresis; followed by one-time application of the agents. Sensitivity was assessed by tactile, air blast, and cold-graded thermal tests(CGTTs) before and immediately after application, after one week, and at the end of the first, third, and sixth months. Statistical analysis Statistical analysis was done by repeated measures ANOVA for within-group comparison. Intergroup comparison was done using one-way ANOVA and Tukey's post-hoc test. Results All the groups showed a statistically significant reduction in dentin hypersensitivity (p<0.001). The reduction inhypersensitivity in various groups can be graded as group II (3.578/1.800/1.556) > group IV (3.367/1.755/1.555) > group I (2.3781/1.022/0.822) > group III (2.222/0.911/0.778) as evaluated by tactile, air blast, and cold-graded thermal tests, respectively. Group II and group IV presented a significant reduction in sensitivity levels consistent for up to six months. Conclusion Nano-hydroxyapatite and pro-argin can be used effectively for reducing dentin hypersensitivity. Iontophoresis can be a valuable adjunct for their improved delivery, enhancing and prolonging their effectiveness.

Enhanced combustion reaction and energy output of Al based energetic materials through introducing perfluorocarbon

Introducing additional oxidizers in aluminized explosives is an effective way to improve energy performance by enhancing the secondary combustion reaction. In this work, perfluorocarbon as oxidizer has been introduced into TATB/Al based energetic materials to improve combustion reaction and energy output performance. The uniform TATB/Al/perfluorocarbon composites are prepared through acoustic resonance mixed technology, and the energy and pressure output performance are fully studied in air blast and underwater explosion. A significantly exothermic peak derived from the reaction between fluorine and Al is observed between 540 ℃ and 580 ℃ for TATB/Al/perfluorocarbon. The heat of explosion of TATB/Al/perfluorocarbon is increased first and then decreased with F/Al ratio from 0 to 0.608. The highest heat of explosion is 6021 J/g for TATB/Al/perfluorocarbon with F/Al ratio of 0.274. Furthermore, the enhanced working capacity, the significantly enlarged fireball and relatively high overpressure are obtained for TATB/Al/perfluorocarbon. More importantly, the shock impulse and first bubble oscillation time of TATB/Al/perfluorocarbon have been increased by 23.2% and 21.18% during underwater explosion, respectively. The results further illustrate that adding perfluorocarbon is a feasible approach to enhance energy output due to combustion reaction between fluorine and Al, which can be applied in explosives and propellants.

Dynamic response of square sandwich panels with stagger-layered honeycomb cores under intensive near-field air blast loading

Metallic honeycomb sandwich panels have been widely used in energy dissipation due to large plastic deformation under impact/blast loading. In this paper, the dynamic response of a honeycomb sandwich panel with stagger-layered core under intensive near-field air blast loading is investigated. Comparative experiments are conducted for stagger-layered and typical honeycomb sandwich panels with the same geometrical size and mass. Numerical simulation has been undertaken based on the experiments. Numerical results coincide well with experimental results on the deformation/failure modes and center-point deflection of back face sheet. The influence of layer number as well as the geometrical parameters on the energy absorption ability of sandwich panels is clarified. Results show that stagger-layer arrangement of honeycomb core greatly improves energy dissipation capability of sandwich panels compared to typical one with the same mass. The increase of layer number and cell size benefits this effect. These findings indicates that core stagger-layer arrangement is a well choice to improve energy dissipation ability of sandwich panels under air blast loading, especially for highly intensive near-field blast loading.

Effect of Liquid Nitrogen Freezing Temperature on the Muscle Quality of Litopenaeus vannamei.

The implications of different liquid nitrogen freezing (LNF) temperatures (-35 °C, -65 °C, -95 °C, and -125 °C) on the ice crystal and muscle quality of white shrimp (Litopenaeus vannamei) were investigated in this essay. The results showed that better muscle quality was maintained after LNF treatment compared to that after air blast freezing (AF) treatment. As the freezing temperature of liquid nitrogen decrease, the freezing speed accelerated, with the freezing speed of LNF at -125 °C being the fastest. However, an excessively fast freezing speed was not conducive to maintaining the quality of shrimp. Among all the freezing treatments, LNF at -95 °C led to the lowest thawing losses and cooking losses, and the highest L* values, indicating that LNF at -95 °C could keep the water holding capacity of frozen shrimp better than that with other freezing methods. At the same time, LNF at -95 °C resulted in higher water holding capacity, and hardness values for shrimps than those with other frozen treatments (p < 0.05). In addition, the results of the water distribution of shrimps showed that treatment with a -95 °C LNF reduced the migration rate of bound and free water. Meanwhile, the microstructural pores of shrimps in the -95 °C LNF group were smaller, indicating that the ice crystals generated during -95 °C LNF were relatively smaller than those generated via other frozen treatments. In conclusion, an appropriate LNF temperature (-95 °C) was beneficial for improving the quality of frozen shrimp, and avoiding freezing breakage.

Quantifying pesticide emissions for drift deposition in comparative risk and impact assessment

Estimating emissions of chemical pesticides used in agriculture is an essential component in evaluating the potential toxicity-related impacts on humans and ecosystems in various comparative risk and impact assessment frameworks, such as life cycle assessment, environmental footprinting, absolute environmental sustainability assessment, chemical substitution, and risk prioritization. Emissions related to drift deposition—usually derived from drift experiments—can reach non-target areas, and vary as a function of crop characteristics and application technique. We derive cumulative drift deposition fractions for a wide range of experimental drift functions for use in comparative and mass-balanced approaches. We clarify that cumulative drift deposition fractions require to integrate the underlying drift functions over the relevant deposition area and to correct for the ratio of deposition area to treated field area to arrive at overall mass deposited per unit mass of applied pesticide. Our results show that for most crops, drift deposition fractions from pesticide application are below 0.03 (i.e. 3% of applied mass), except for grapes and fruit trees, where drift fractions can reach 5% when using canon or air blast sprayers. Notably, aerial applications on soybeans can result in significantly higher drift deposition fractions, ranging from 20% to 60%. Additionally, varying the nozzle position can lead to a factor of five differences in pesticide deposition, and establishing buffer zones can effectively reduce drift deposition. To address remaining limitations in deriving cumulative drift deposition fractions, we discuss possible alternative modelling approaches. Our proposed approach can be implemented in different quantitative and comparative assessment frameworks that require emission estimates of agricultural pesticides, in support of reducing chemical pollution and related impacts on human health and the environment.

Changing the working conditions of the mineral wool cupola during the transition from an open type to a closed one

The widespread use in the industry of mine furnaces of the wagon type requires the organization of management of their gasdynamic and thermal regime. In the mode of operation of a cupola with an open grate, its thermal mode is characterized mainly by the peripheral movement of gases with a significant difference in the ratio of heat capacities of gas flows and materials. The use of forced removal of exhaust gases from the shaft furnace contributes to an earlier transition from a peripheral to a predominantly central movement mechanism. By increasing the degree of rarefaction on the grate to 0,71‒0,73 bar, it is possible to increase the level of melt temperature, temperature pressure and air blast flow, exhaust gas temperature while improving the conditions of heat exchange between gases and heated materials. This process will be accompanied by a continuous decrease in the productivity of the unit with an improvement in the stability of the melting process. A further increase in the level of rarefaction on the grate contributes to the gradual transition of the mechanism of movement of gases from the peripheral to the central one with a deterioration in the parameters of the wagon melting.