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In an era of increasing environmental awareness, it is very important to work towards eliminating or at least reducing as many harmful industrial substances as possible. However, the implementation of green chemistry methods for wastewater treatment can be difficult especially due to complexity, the high cost of reagents, and the required long process time. This paper focuses on using waste iron (WI) to remove two kinds of amaranth dye commonly used in industry. To enhance the process, UV irradiation and hydrogen peroxide were used. The novelty of the research was the use of efficient and reusable WI as a heterogeneous catalyst in the process. WI material characteristics was done before and after the process using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF). Zeta potential, size characterization, circularity, and direct band gap were also determined. As a result of treatment complete decolorization of both dyes was achieved, as well as 99% absorbance removal after 15-min process time. The total organic carbon (TOC) decrease after 60-min process time was in the range from 86.6 to 89.8%. Modified pseudo-second-order reaction reflects obtained results of treatment efficiency. Treatment results, confirmed by WI material characterization, indicate satisfactory stability of the catalyst and good oxidation capacity.

Rapid global industrialization constantly impacts the environment by discharging pollutants. Therefore, various materials are currently being investigated for environmental applications, including two-dimensional (2D) MXenes. Herein, we focus on MXene-enabled technologies for removing inorganic and organic contaminants present in gaseous and liquid forms, especially organic dyes, pharmaceuticals, and solid pollutants. We foresee a considerable potential for MXene-enabled technologies to remove heavy ions and radionuclides and recover precious elements. We show that MXenes could efficiently inactivate microorganisms without harming the environment. Finally, we discuss the associated opportunities and challenges in MXenes’ surface chemistry, semiconducting activity, interfacial effects, adsorption, and photocatalysis. Altogether, this article showcases outstanding opportunities for MXenes in the rapidly growing field of environmental applications. Graphical abstract

Examinations of two-component mixtures, namely: triphenylamine + centralite I (TPA + CI) and triphenylamine + akardite II (TPA + AkaII) were carried out using differential scanning calorimetry (DSC), which served to determine phase diagrams. Experimental data were described with NRTL model and eutectic points for both systems were determined. For TPA + CI system, they were equal to xEu,TPA = 0.2899, TEu = 62.9 °C, whereas for TPA + AkaII system they amounted to xEu,TPA = 0.7868, TEu = 117.5 °C. Granules contain mixtures of eutectic composition were obtained. The physicochemical and thermal properties of resultant single base granules were studied. The helium density of both granules was approx. 1.47 g cm−3, the average dynamic force amounted to 0.55–0.60 bar−1 s−1, and the calorific value ranged from 3060 to 3095 J g−1. Both granules should be chemically stable for 10 years of storage at 25 °C; they meet the requirements of STANAG 4582 standard. DSC analysis of decomposition processes was used to determine kinetic parameters and to adjust the chemical reaction model of nth order with autocatalysis (CnB). Reaction order ranged from 2.6 to 3.0, while the activation energy was similar (197–198 kJ mol−1). Based on examination of thermal properties, it was observed that both eutectic mixtures of stabilizers prevent the decomposition reaction more efficiently than the use of individual compounds as stabilizers.

Rapidly developing nanotechnologies and their integration in daily applications may threaten the natural environment. While green methods of decomposing organic pollutants have reached maturity, remediation of inorganic crystalline contaminants is major problem due to their low biotransformation susceptibility and the lack of understanding of material surface-organism interactions. Herein, we have used model inorganic 2D Nb-based MXenes coupled with a facile shape parameters analysis approach to track the mechanism of bioremediating 2D ceramic nanomaterials with green microalgae Raphidocelis subcapitata. We have found that microalgae decomposed the Nb-based MXenes due to surface-related physicochemical interactions. Initially, single and few-layered MXene nanoflakes attached to microalgae surfaces, which slightly reduced algal growth. But with prolonged surface interaction, the microalgae oxidized MXene nanoflakes and further decomposed them into NbO and Nb2O5. Since these oxides were nontoxic to microalgal cells, they consumed Nb-oxide nanoparticles by an uptake mechanism thus enabling further microalgae recovery after 72 h of water treatment. The uptake-associated nutritional effects were also reflected by cells’ increased size, smoothed shape and changed growth rates. Based on these findings, we conclude that short- and long-term presence of Nb-based MXenes in freshwater ecosystems might cause only negligible environmental effects. Notably, by using 2D nanomaterials as a model system, we show evidence of the possibility of tracking even fine material shape transformations. In general, this study answers an important fundamental question about the surface interaction-associated processes that drive the mechanism of 2D nanomaterials’ bioremediation as well as provides the fundamental basis for further short- and long-term investigations on the environmental effects of inorganic crystalline nanomaterials.

The dynamics of the ion flux expelled by a 0.5 kW-class Hall thruster supplied with krypton was examined in a wide range of discharge voltages. A homemade Faraday probe installed onto a rotary arm was used for reconstructing angular profiles of the plasma plume 0.5 m downstream of the thruster exit plane. The time dependence of the ion current was measured along the thruster axis. For investigating the signal dynamics, a Fourier approach as well as methods of nonlinear time series analysis like bifurcation diagrams and recurrence plot techniques were applied, which are of interest for chaotic behavior identification. Along with the well-known breathing mode (10—30 kHz), other characteristic groups of oscillations were also detected. The bifurcation diagram revealed a drastic transition between large and small amplitude oscillating regimes while varying the discharge voltage from 550 to 700 V. In parallel to this transition, recurrent plots display a qualitative change from a periodic (or quasi periodic) oscillating regime to much less predictable dynamics.

A prototype of krypton Hall-effect thruster (HET) of 0.5 kW nominal power and a dedicated diagnostic system for ion current collection were designed in the laboratory of plasma space propulsion (PlaNS) of the Institute of Plasma Physics and Laser Microfusion (IPPLM) in Warsaw. The diagnostic system consisting of a collimated Faraday Cup (FC) and a Planar Probe with Guarding Ring, named also Faraday Probe (FP) was intended to capture both temporal and spatial ion current variation, allowing to analyze not only ion current dynamics locally but also to estimate the total ion current value and a plasma jet divergence. Reliable engine operation provided by stability of plasma in a discharge channel of the thruster is unambiguously reflected in the oscillations of the discharge current. The so-called breathing mode, categorized as ionization instability with frequencies in the range of 10–30 kHz, is commonly recognized in the HET’s discharge current. Rising of instabilities makes it difficult to increase the specific impulse effectively by just simply attempting to operate thruster in high-voltage regime because it may result in very irregular thruster functioning and often to ceasing of plasma. Discharge current oscillations should also be strongly reflected in the ion current. Indeed, a similar to discharge current behavior was observed in the recorded FC and FP ion current signals. By changing thruster operating conditions, like discharge voltage and magnitude of B-field, transitions between smooth and oscillating current regimes were examined. Studying the ion current dynamics seems particularly important, since it is predicted that the control of discharge instabilities may be crucial to improve the performance of HETs in the future.

Fibre metal laminates (FMLs) are attractive construction materials, especially for use in aerospace and transport facilities. Throughout their service life, thin-walled structures made of FMLs are exposed to static and dynamic loads, as well as corrosion and the unfavourable influence of environmental conditions. The paper presents an experimental analysis of the combined mechanical and environmental long-term behaviour of carbon-based fibre metal laminates and their variants with protective glass layers. The Al alloy/CFRP and Al alloy/GFRP/CFRP laminates in a 3/2 configuration were used. The tested laminates were subjected to 1500 thermal cycles with a temperature range of 130 °C. The static and fatigue interlaminar shear strengths were tested before and after thermal conditioning. It was shown that the stable stiffness reduction in the tested laminates was observed with increasing fatigue cycles, due to the progressive fatigue damage accumulation. The thermally cycled laminates feature slightly smoother stiffness loss, while a more rapid decrease was observed in thermally untreated laminates. Moreover, the fatigue life of the tested laminates subjected to thermal cycling revealed nine times fewer fatigue cycles of laminates with glass protectors after thermal cycles in comparison to the laminates not subjected to thermal cycling.

The Aleutian mink disease virus (AMDV) is one of the most serious threats to modern mink breeding. The disease can have various courses, from progressive to subclinical infections. The objective of the study was to provide a comparative molecular characterization of isolates of AMDV from farms with a clinical and subclinical course of the disease. The qPCR analysis showed a difference of two orders of magnitude between the number of copies of the viral DNA on the farm with the clinical course of the disease (105) and the farm with the subclinical course (103). The sequencing results confirm a high level of homogeneity within each farm and variation between them. The phylogenetic analysis indicates that the variants belonging to different farms are closely related and occupy different branches of the same clade. The in silico analysis of the effect of differences in the sequence encoding the VP2 protein between the farms revealed no effect of the polymorphism on its functionality. The close phylogenetic relationship between the isolates from the two farms, the synonymous nature of most of the polymorphisms and the potentially minor effect on the functionality of the protein indicate that the differences in the clinical picture may be due not only to polymorphisms in the nucleotide and amino acid sequences, but also to the stage of infection on the farm and the degree of stabilization of the pathogen-host relationship.

The work explores the possibilities of application of ultrasonic testing in the assessment of fibre metal laminates. Basic problems concerning the use of ultrasonic methods in the research of laminates are explained, and methods for solving these problems are suggested. Tests were conducted using two phased array methods: ultrasonic pulse-echo and through transmission. The efficiency of both selected ultrasonic methods are compared with respect to detecting and dimensioning defects in laminate structures. Based on the analyses and proposed solutions, it has been proven that the developed through transmission phased array (TTPA) method ensures a much more effective, in terms of quality and quantity, assessment of the condition of hybrid laminates than conventional ultrasonic methods, irrespective of the degree of surface deformation and the type of laminate structure.

The purpose of this paper is to investigate the impact behaviour and damage characterization of carbon fibre reinforced aluminium hybrid laminates (Al/CFRP) in comparison to classic carbon fibre reinforced polymer (CFRP) at low-velocity and low-energy impact. Impact damage characteristic with damage initiation and progression, internal failure modes and understanding of the role of the metal layers in the impact behaviour under low-energy were examined and discussed. The damage mechanism of the tested laminates is very complex. There is an internal degradation of the material, with the plastic deformation in case of fibre metal laminates. Characteristic matrix cracks (bending and shearing cracks) running at the fibre–matrix interface in composite layers are the first damage mode. The critical damage mode is delaminations observed between composite layers with different orientation as well as delaminations at the metal–composite interface in fibre metal laminates. For the tested materials, particularly carbon fibre reinforced composites, the absorbed impact energy is mainly connected with elastic response and damage of the laminate. In case of fibre metal laminates the absorbed energy is also connected with plastic deformation of the laminate, occurring especially in the metal layers. High impact resistance of fibre metal laminates indicates that metal (aluminium) layers may prevent delamination propagation and impactor penetration.

Possible simplifications in modeling the fatigue growth of cracks in plates under arbitrary mode I stress distributions are investigated by the WF2D method based on 2D weight functions. This is important if analytic methods are used with some restrictions imposed on the stress distribution and crack shapes. The performed analyses reveal a small impact of the idealized initial crack shape (aspect ratio) used to replace the actual shape of the defect. The data of these analyses also confirm that the averaging of the stress distribution over the entire crack plane may be a reasonable simplification in the analytic investigation of crack growth.

An overview of recent advances in applications of currently the most energetic X-ray laser at 21 nm is given. The unique parameters of this half-cavity based X-ray laser such as record output energy of 10 mJ, highly symmetric beam, robustness and reproducibility, have made it possible to carry out a number of multidisciplinary scientific projects featuring novel applications of intense coherent X-ray radiation. Selected results obtained in these experiments are reviewed, including X-ray laser probing of dense plasmas, measurements of transmission of focused soft X-ray radiation at intensities of up to 1012 W cm-2, measurements of infrared laser ablation rates of thin foils, and ablative microstructuring of solids.

A potentially promising treatment of metastatic cancer is the systemic delivery of oncolytic adenoviruses. This requires engineering viruses which selectively replicate in tumors. We have constructed such an oncolytic adenovirus, OAS403, in which two early region genes are under the control of tumor-selective promoters that play a role in two key pathways involved in tumorigenesis. The early region E1A is controlled by the promoter for the E2F-1 gene, a transcription factor that primarily upregulates genes for cell growth. The E4 region is under control of the promoter for human telomerase reverse transcriptase, a gene upregulated in most cancer cells. OAS403 was evaluated in vitro on a panel of human cells and found to elicit tumor-selective cell killing. Also, OAS403 was less toxic in human hepatocyte cultures, as well as in vivo when compared to an oncolytic virus that lacked selective E4 control. A single intravenous injection of 3 x 10(12) vp/kg in a Hep3B xenograft mouse tumor model led to significant antitumor efficacy. Additionally, systemic administration in a pre-established LNCaP prostate tumor model resulted in over 80% complete tumor regressions at a tolerable dose. Vector genome copy number was measured in tumors and livers at various times following tail vein injection and showed a selective time-dependent increase in tumors but not livers over 29 days. Furthermore, efficacy was significantly improved when OAS403 treatment was combined with doxorubicin. This virus holds promise for the treatment of a broad range of human cancers including metastatic disease.

Oncolytic adenoviral vectors selectively replicate in and lyse human tumor cells, providing a promising means for targeted tumor destruction. However, oncolytic vectors have limited capacity for incorporation of additional genetic material that could encode therapeutic transgenes and/or transcriptional regulatory control elements to augment the efficacy and/or safety of the vector. Therefore, we hypothesized that coadministration of an oncolytic vector with a replication-defective, gutless adenoviral vector encoding a therapeutic transgene would result in replication of both vectors within a tumor and potentiate antitumor efficacy relative to the use of either vector alone. We constructed gutless vectors encoding the murine granulocyte-macrophage colony-stimulating factor (AGVmGMF) or human tumor necrosis factor alpha-related apoptosis-inducing ligand (AGVhTRAIL) gene and tested the ability of these vectors to augment the efficacy of an oncolytic vector (Ar6pAE2fE3F) in a potentiating vector strategy. In Hep3B cells in vitro, cotreatment with Ar6pAE2fE3F increased transgene expression from AGVhTRAIL and permitted replication of AGVhTRAIL, suggesting that an oncolytic vector can propagate gutless vector spread in vivo. In pre-established Hep3B xenograft tumors, neither gutless vector alone inhibited tumor growth; however, coadministration of AGVmGMF or AGVhTRAIL with Ar6pAE2fE3F significantly reduced tumor growth relative to Ar6pAE2fE3F alone. Additionally, use of AGVhTRAIL with Ar6pAE2fE3F increased the number of complete or partial tumor regressions observed at study end. These data provide evidence that coadministration of an oncolytic vector with a gutless vector holds promise for potentiating tumor ablation efficacy.

The enthalpy change associated with aerobic growth of E. coli K12 on minimal media with succinic acid as sole carbon and energy source, determined by flow microcalorimetry (with aerobic mixing cell) was 733.01±15.32 kJ·mol−1. Molar growth yield was 39.6±1.2 g·mol−1. When the microcalorimetric growth was limited by oxygen supply, the power-time curve was altered and the total heat evolved was less than the enthalpy change. The maximum thermal output corresponding to a fully aerobic growth in the calorimetric cell was 1.89×10−3 W·ml−1. Thus, the oxygen uptake rate was about 0.39 ml O2·h−1·ml−1.

The influence of d-amphetamine on the acquisition of light-contingent bar-pressing was assessed in rats in a two-lever operant task as a function of dose and incentive value of the sensory reinforcer. Relative to saline-injected controls, amphetamine increased the probability of discriminated responding on the active reward-bar at the 0.75 but not at the 2.50 mg/kg dosage level. Further, only at the lower dose was the effect of incentive condition significant, with animals receiving variant light-onset emitting a greater percentage of presses on the active bar than animals receiving invariant light-onset. It was concluded that low doses of amphetamine do not enhance all categories of behavior in the rat in a learning situation, but selectively facilitate only those responses directed by the reinforcement contingencies. In addition, the poor performance observed for animals injected with the higher dosage in the present experiment may have been due to the stimulated perseveration of stereotypic behavior patterns which were incompatible with the task requirements.

The purpose of this experiment was to determine whether age differences in amounts of wheel running of starved rats were due to the frequency of bursts of running, to the average duration of bursts, to speed, or to any combination of these parameters. The experiment was carried out according to a 3 by 2 by 2 mixed model design. The independent variables were age (67, 293, and 746 days old at the start of starvation), food deprivation (total starvation vs ad lib), and occasion of measurement (initial vs maximum activity). The dependent variables were number of wheel revolutions, number of bursts of activity, number of seconds of running per burst, and revolutions per second. The results indicated that acutely starved rats run more often, for longer periods, and at higher speeds than do sated rats, and that with increased age rats run less often, for a shorter time, and at slower speeds.

Are there age-related decrements in the re-entrainment of food intake of rats following an inversion of the light-dark cycle? An experiment using 17 male rats was carried out according to a 2 by 2 by 7 design, with repeated measures on the last two factors, representing age of rat (220 and 785 days), time of day (0600-1800 h vs. 1800-0600 h), and daysets (0-6). The primary dependent variable was grams of food eaten during each 12-h period. The results indicate that prior to the light reversal the older rats ate more during the light phase of the light-dark cycle than the younger rats, but did not differ from them during the dark phase; and that the older rats entrained their food intake at a slower absolute rate than the younger rats, but at an equal relative rate. These results suggest that senescent rats are as adaptable to changes in their environment as mature rats.

The purpose of this experiment was to determine whether or not there were age differences in the effects of increasing durations of food deprivation on food intake in rats. The experiment was carried out according to a 3 by 3 by 3 by 7 mixed design consisting of three age groups of 12 female Sprague-Dawley rats each (4, 11, and 24 months), subdivided into three sequence-effects control groups (ABC, BCA, CAB), with each rat exposed to each food-deprivation duration (24, 48, and 96 h), and refeeding measured for 7 days. The dependent variables were: latency to eat, amount of food per day consumed during refeeding, and body weight. Prior to food deprivation , the 4-month-old rats ate less than the 11-month-old rats or the 24-month-old rats , but these differences were proportional to age differences in body weight. The effects of duration of deprivation, order, and days of refeeding were proportional across age, suggesting equal responsivity to the effects of these factors on food intake across a large segment of the life span of the female rat.

The purpose of this experiment was to determine the time course and peak effects of methamphetamine on wheel-running activity of food-deprived rats and to determine whether degree of food deprivation and/or predeprivation levels interact with dosage to influence running activity. The experiment was carried out according to a 4 by 3 by 2 by 5 design, representing four dosage levels of methamphetamine HC1 (0.00, 0.75, 1.50, and 3.00 m g/kg), three food-deprivation conditions (90%, 80%, and 70% of ad lib body weight), two blocks of rats formed on the basis of predeprivation levels of running, and five hourly samples of running activity. The results indicated that the peak effects of methamphetamine on running activity occur with a dose of 1.50 mg/kg, during the first hour after injection, and are additive to the effects of food deprivation and predeprivation running levels.

The purpose of the two experiments was to determine whether or not changes in blood-glucose level affect wheel-running activity of food-deprived rats. Fructose, sucrose, adrenalin, insulin, and saline were injected into food-deprived rats, and their effects on wheel-running activity determined. Adrenalin and insulin decreased running activity, but fructose and sucrose did not. The results indicated that changes in blood-glucose level per se do not seem to be effective stimuli in the control of running activity of food-deprived rats.

When young rats, as well as humans, are presented with diets that differ in caloric density (kilocalories/gram), they prefer the calorically dense diet. How these preferences change with age is not known. A 2 by 2 by 3 by 7 experiment, representing strain, age, caloric-density difference, and day sets, was carried out in order to determine the influence of these factors on preference for calorically dense diets. The results indicated that, depending on the strain, old rats prefer calorically dense diets either to an equal degree or to a lesser degree than do young rats.