Mechanochemical recycling of cellulose multilayer carton packages to produce micro and nanocellulose from the perspective of techno-economic and environmental analysis.

Despite being composed of recyclable materials, the main technological challenge of multilayer carton packs involves the efficient decompatibilization of the cellulosic, polymeric, and metallic phases. Here, a simple two-step mechanochemical process is described that uses only aqueous media and mechanical force to promote phase separation in order to fully recycle multi-layer carton packaging. The first step produces value-added micro- and nanocellulose, while in the second step, aluminum is extracted, forming precipitated aluminum and aluminum oxyhydroxides. Solid polyethylene (PE) remains with a degree of purity defined by the process efficiency. The results show that cellulose is efficiently extracted and converted into micro- and nanocellulose after 15 min of milling. In the second stage, approximately 90% of the aluminum is extracted from the PE after 15 min of milling. Due to the separation and drying medium conditions, the finely divided particles of extracted aluminum also have oxyhydroxides in their composition. It is believed that a passivation layer forms on the metallic aluminum particle. The techno-economic analysis revealed a positive net present value (NPV) of $17.5 million, with a minimum selling price of 1.62 USD/kg of cellulose. The environmental analysis concluded that most of the environmental impact of the process is associated with the entry of carton packages into the system, incorporating a small environmental load related to the industrial process. The results indicate a promising option toward a circular economy and carbon neutrality.

Aluminum zirconate nanoparticles in etch and rinse adhesive to caries affected dentine: An in-vitro scanning electron microscopy, elemental distribution, antibacterial, degree of conversion and micro-tensile bond strength assessment.

To incorporate different concentrations of Al2O9Zr3 (1%, 5%, and 10%) nanoparticles (NP) into the ER adhesive and subsequently assess the impact of this addition on the degree of conversion, µTBS, and antimicrobial efficacy. The current research involved a wide-ranging examination that merged various investigative techniques, including the application of scanning electron microscopy (SEM) for surface characterization of NP coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, µTBS testing, and microbial analysis. Teeth were divided into four groups based on the application of modified and unmodified three-step ER adhesive primer. Group 1 (0% Al2O9Zr3 NPs) Control, Group 2 (1% Al2O9Zr3 NPs), Group 3 (5% Al2O9Zr3 NPs), and Group 4 (10% Al2O9Zr3 NPs). EDX analysis of Al2O9Zr3 NPs was performed showing elemental distribution in synthesized NPs. Zirconium (Zr), Aluminum (Al), and Oxides (O2). After primer application, an assessment of the survival rate of Streptococcus mutans was completed. The FTIR spectra were analyzed to observe the characteristic peaks indicating the conversion of double bonds, both before and after the curing process, for the adhesive Etch and rinse containing 1,5,10 wt% Al2O9Zr3 NPs. µTBS and failure mode assessment were performed using a Universal Testing Machine (UTM) and stereomicroscope respectively. The µTBS and S.mutans survival rates comparison among different groups was performed using one-way ANOVA and Tukey post hoc (p = .05). Group 4 (10 wt% Al2O9Zr3 NPs + ER adhesive) specimens exhibited the minimum survival of S.mutans (0.11 ± 0.02 CFU/mL). Nonetheless, Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) displayed the maximum surviving S.mutans (0.52 ± 0.08 CFU/mL). Moreover, Group 2 (1 wt% Al2O9Zr3 NPs + ER adhesive) (21.22 ± 0.73 MPa) samples displayed highest µTBS. However, the bond strength was weakest in Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) (14.13 ± 0.32 MPa) study samples. The etch-and-rinse adhesive exhibited enhanced antibacterial activity and micro-tensile bond strength (µTBS) when 1% Al2O9Zr3 NPs was incorporated, as opposed to the control group. Nevertheless, the incorporation of Al2O9Zr3 NPs led to a decrease in DC. RESEARCH HIGHLIGHTS: 10 wt% Al2O9Zr3 NPs + ER adhesive specimens exhibited the minimum survival of S.mutans. 1 wt% Al2O9Zr3 NPs + ER adhesive samples displayed the most strong composite/CAD bond. The highest DC was observed in Group 1: 0 wt% Al2O9Zr3 NPs + ER adhesive.

Investigating the role of carbon doping on the structural and energetic properties of small aluminum clusters using quantum Monte Carlo.

In this study, we investigate the energetics of small aluminum clusters doped with a carbon atom using several computational methods, including diffusion quantum Monte Carlo, Hartree-Fock (HF), and density functional theory. We calculate the lowest energy structure, total ground-state energy, electron population distribution, binding energy, and dissociation energy as a function of the cluster size of the carbon-doped aluminum clusters compared with the undoped ones. The obtained results show that carbon doping enhances the stability of the clusters mainly due to the electrostatic and exchange interactions from the HF contribution gain. The calculations also indicate that the dissociation energy required to remove the doped carbon atom is much larger than that required to remove an aluminum atom from the doped clusters. In general, our results are consistent with available theoretical and experimental data.

Catechin Photolysis Suppression by Aluminum Chloride under Alkaline Conditions and Assessment with Liquid Chromatography-Mass Spectrometry.

Tea is rich in catechins and aluminum. In this study, the process of catechin photolysis was applied as a model for examining the effects of aluminum chloride (AlCl3) on the structural changes of catechin and the alteration of aluminum complexes under blue light irradiation (BLI) at pH 8 using liquid chromatography and mass spectrometry techniques. Additionally, the effects of anions on catechin upon the addition of AlCl3 and treatment with BLI were also studied. In this study, when 1 mM catechin was treated with BLI, a superoxide anion radical (O2•-) was generated in an air-saturated aqueous solution, in addition to forming a dimeric catechin (proanthocyanidin) via a photon-induced redox reaction. The relative percentage of catechin was found to be 59.0 and 95.7 for catechin treated with BLI and catechin upon the addition of 1 mM AlCl3 treated with BLI, respectively. It suggested that catechin treated with BLI could be suppressed by AlCl3, while AlCl3 did not form a complex with catechin in the photolytic system. However, under the same conditions, it was also found that the addition of AlCl3 inhibited the photolytic formation of O2•-, and reduced the generation of proanthocyanidin, suggesting that the disconnection of proanthocyanidin was achieved by AlCl3 acting as a catalyst under treatment with BLI. The influence of 1 mM fluoride (F-) and 1 mM oxalate (C2O42-) ions on the photolysis of 1 mM catechin upon the addition of 1 mM AlCl3 and treatment with BLI was found to be insignificant, implying that, during the photolysis of catechin, the Al species were either neutral or negatively charged and the aluminum species did not form a complex with anions in the photolytic system. Therefore, aluminum, which is an amphoteric species, has an inherent potential to stabilize the photolysis of catechin in an alkaline conditions, while suppressing the O2•- and proanthocyanidin generation via aluminum ion catalysis in the catechin/Al system under treatment with BLI.

Dose profiles and x-ray energy optimization for microbeam radiation therapy by high-dose, high resolution dosimetry using Sm-doped fluoroaluminate glass plates and Monte Carlo transport simulation.

Microbeam radiation therapy (MRT) utilizes highly collimated synchrotron generated x-rays to create narrow planes of high dose radiation for the treatment of tumors. Individual microbeams have a typical width of 30-50 µm and are separated by a distance of 200-500 µm. The dose delivered at the center of the beam is lethal to cells in the microbeam path, on the order of hundreds of Grays (Gy). The tissue between each microbeam is spared and helps aid in the repair of adjacent damaged tissue. Radiation interactions within the peak of the microbeam, such as the photoelectric effect and incoherent (atomic Compton) scattering, cause some dose to be delivered to the valley areas adjacent to the microbeams. As the incident x-ray energy is modified, radiation interactions within a material change and affect the probability of interactions, as well as the directionality and energy of ionizing particles (electrons) that deposit energy in the valley regions surrounding the microbeam peaks. It is crucial that the valley dose between microbeams be minimal to maintain the effectiveness of MRT. Using a monochromatic x-ray source with x-ray energies ranging from 30 to 150 keV, a detailed investigation into the effect of incident x-ray energy on the dose profiles of microbeams was performed using samarium doped fluoroaluminate (FA) glass as the medium. All dosimetric measurements were carried out using a purpose-built fluorescence confocal microscope dosimetric technique that used Sm-doped FA glass plates as the irradiated medium. Dose profiles are measured over a very a wide range of x-ray energies at micrometer resolution and dose distribution in the microbeam are mapped. The measured microbeam profiles at different energies are compared with the MCNP6 radiation transport code, a general transport code which can calculate the energy deposition of electrons as they pass through a given material. The experimentally measured distributions can be used to validate the results for electron energy deposition in fluoroaluminate glass. Code validation is necessary for using transport codes in future treatment planning for MRT and other radiation therapies. It is shown that simulated and measured micro beam-profiles are in good agreement, and micrometer level changes can be observed using this high-resolution dosimetry technique. Full width at 10% of the maximum peak (FW@10%) was used to quantify the microbeam width. Experimental measurements on FA glasses and simulations on the dependence of the FW@10% at various energies are in good agreement. Simulations on energy deposited in water indicate that FW@10% reaches a local minimum around energies 140 keV. In addition, variable slit width experiments were carried out at an incident x-ray energy of 100 keV in order to determine the effect of the narrowing slit width on the delivered peak dose. The microbeam width affects the peak dose, which decreases with the width of the microbeam. Experiments suggest that a typical microbeam width for MRT is likely to be between 20-50 µm based on this work.

Arsenite removal from groundwater by aerated electrocoagulation reactor with Al ball electrodes: Human health risk assessment.

The application of conventional electrocoagulation (EC) process for removal of As(III) from groundwater suffers from the need of external oxidation agent for oxidation of As(III) to As(V). To tackle this limitation, an aerated EC reactor for the removal of As(III) from groundwater was evaluated in this study. The effect of initial pHi, air flow rate, applied current, and electrode height in the EC reactor was examined. The experimental results showed that removal of arsenic mostly dependent on the applied current, electrode height in EC reactor, and air flow rate. The As(III) removal efficiency (99.2%) was maximum at pHi of 7.5, air flow rate of 6 L min-1, applied current of 0.30 A, and electrode height in EC reactor of 5 cm, with an total operating cost of 0.583 $ m-3. Furthermore, the carcinogenic risk (CR) and non-carcinogenic risk of arsenic (As) was in the range of tolerable limits at all operating conditions except applied current of 0.075 A at the end of the aerated EC process to remove As from groundwater. The present EC reactor process is able to remove As(III) from groundwater to below 10 µg L-1, which is maximum contaminant level of arsenic in drinking water according to the World Health Organization (WHO).

The bioaccessibility and fractionation of arsenic in anoxic soils as a function of stabilization using low-cost Fe/Al-based materials: A long-term experiment.

Arsenic (As)-contaminated soils occur widely worldwide. In the present study, three low-cost Fe/Al-based materials, including red soil (RS), sponge iron filter (SIF) and Al-based water treatment sludge (WTS), were applied as amendments to remediate As-contaminated soils under anoxic conditions. After 180 d of incubation, the proportion of the sum of nonspecifically absorbed As (F1) and specifically absorbed As (F2) to the total As was reduced by 6%, 52% and 13% with 5% of RS, SIF and WTS addition, respectively, compared to the control soil (31%). The results showed that among the three amendments, SIF was the most effective at decreasing As bioaccessibility in soils. Compared with RS and WTS, SIF intensified the decrease of labile fractions and the increase of unlabile fractions, and the redistribution of the amorphous oxide-bound fraction (F3) and crystalline hydrous oxide-bound fraction (F4) occurred in the SIF-amended soil. Moreover, the As stabilization processes were divided into two stages in the control and RS-amended soil, while the processes were divided into three stages in both SIF- and WTS-treated soil. The As stabilization processes in all treated soils were characterized by the transformation of labile fractions into more immobilizable fractions, except for F4 transforming into F3 in the first stage in SIF-amended soil. Correspondingly, inner-surface complexation and occlusion within Fe/Al hydroxides were the common driving mechanisms for the transformation of As fractions. Therefore, taking into consideration the results of this study, SIF could be a more promising alternative than the other two materials to passivate As in anoxic soils.

Impact of a parallel magnetic field on radiation dose beneath thin copper and aluminum foils.

PURPOSE: The RF coils for magnetic resonance image guided radiotherapy (MRIgRT) may be constructed using thin and/or low-density conductors, along with thinner enclosure materials. This work measures the surface dose increases for lightweight conductors and enclosure materials in a magnetic field parallel to a 6 MV photon beam. METHODS: Aluminum and copper foils (9-127 µm thick), as well as samples of polyimide (17 µm) and polyester (127 µm) films are positioned atop a polystyrene phantom. A parallel plate ion chamber embedded into the top of the phantom measures the surface dose in 6 MV photon beam. Measurements (% of dose at the depth of maximum dose) are performed with and without a parallel magnetic field (0.22T at magnet center). RESULTS: In the presence of a magnetic field, the unobstructed surface dose is higher (31.9%Dmax versus 22.2%Dmax). The surface dose is found to increase linearly with thickness for thin (<25 µm) copper (0.339%Dmax µm-1) and aluminum (0.116%Dmax µm-1) foils. In the presence of a magnetic field the slope is lower (copper: 0.16%Dmax µm-1, aluminum: 0.06%Dmax µm-1). The effect of in-beam foils is reduced due to partial shielding of the surface from contaminant electrons. Copper causes a surface dose increase ≈3 times higher than aluminum of the same thickness, consistent with their relative electron density. Polyester film (127µm) increases the surface dose (to 35% Dmax with field) about as much as a gown (36% Dmax with field), while the increase with polyimide film (17µm) is less than 1% above the open field dose. CONCLUSIONS: Thin copper and aluminum conductors increase surface dose by an amount comparable to a hospital gown. Similarly, enclosure materials made of thin polyester or polyimide film increase surface dose by only a few %Dmax in excess of an unobstructed beam. Based on measurements in this study, in-beam, surface RF coils are feasible for MRIgRT systems.

Toxic (Al, Cd, and Pb) and trace metal (B, Ba, Cu, Fe, Mn, Sr, and Zn) levels in tissues of slaughtered steers: risk assessment for the consumers.

The levels of toxic metals (Al, Cd, Pb) and trace metals (B, Ba, Cu, Fe, Mn, Sr, Zn) were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) in the muscle (sirloin and chuck) and liver from a total of 180 samples of steers (less than 2 years old) (Bos taurus) of foreign and local origin slaughtered on the island of La Palma (Canary Islands, Spain). As regards toxic metals, Al was the metal with the highest contents in both tissues of the foreign steers (3.75 mg/kg in the muscle and 55.3 mg/kg in the liver) and the local steers (5.60 mg/kg in the muscle and 8.65 mg/kg in the liver). In conclusion, the present study confirmed that beef is a source of trace elements, mainly Fe and Zn. In addition, the consumption of this type of beef did not show significant intakes of toxic metals (Al, Cd, and Pb) and, therefore, the consumption of the steer muscle and liver does not pose a toxicological risk for Spanish consumers.

Simultaneous assessment of cell morphology and adhesion using aluminum nanoslit-based plasmonic biosensing chips.

A variety of physiological and pathological processes rely on cell adhesion, which is most often tracked by changes in cellular morphology. We previously reported a novel gold nanoslit-based biosensor that is capable of real-time and label-free monitoring of cell morphological changes and cell viability. However, the preparation of gold biosensors is inefficient, complicated and costly. Recently, nanostructure-based aluminum (Al) sensors have been introduced for biosensing applications. The Al-based sensor has a longer decay length and is capable of analyzing large-sized mass such as cells. Here, we developed two types of double-layer Al nanoslit-based plasmonic biosensors, which were nanofabricated and used to evaluate the correlation between metastatic potency and adhesion of lung cancer and melanoma cell lines. Cell adhesion was determined by Fano resonance signals that were induced by binding of the cells to the nanoslit. The peak and dip of the Fano resonance spectrum respectively reflected long- and short-range cellular changes, allowing us to simultaneously detect and distinguish between focal adhesion and cell spreading. Also, the Al nanoslit-based biosensor chips were used to evaluate the inhibitory effects of drugs on cancer cell spreading. We are the first to report the use of double layer Al nanoslit-based biosensors for detection of cell behavior, and such devices may become powerful tools for anti-metastasis drug screening in the future.

Balancing Container Closure Integrity and Aesthetics for a Robust Aseptic or Sterile Vial Packaging System.

Container closure integrity (CCI) is one of the requirements for a sterile packaging system. For vial-based systems, the capping process is a critical step in creating and ensuring an adequate seal with acceptable CCI. Container closure integrity tests (CCITs) such as the dye ingress and the helium leak rate are two methods among many that, in the appropriate scenario, help to challenge this required attribute. The use of locked-in stopper compression (compression under the crimp seal post capping) enables correlation of these methods to CCI and seal quality. In fact, the overall acceptability of a seal can be evaluated using quantitative and qualitative methods. Usually lost in these assessments is the existence of seal cosmetics as an essential additional seal quality attribute. Unacceptable cosmetic quality can have a major impact on manufacturing (reduced batch output, high yield cost, etc.) and user (perceived low quality, brand image, potential injury, etc.) experiences. Interestingly, the aesthetics of a seal is also impacted by the capping process which is quite complicated because the acceptance criteria for aesthetics of a seal is subjective. Ultimately, this affects commercial manufacturing efficiency and CCI. Here, we present a simple methodology for package selection and evaluated multiple package configurations using locked-in stopper compression (through residual seal force, RSF) measurements and seal aesthetics analyses (using a semi-quantitative aesthetics scale). The integrity of the seals was analyzed using multiple CCIT methods. We determined that component dimensions such as the seal length play a major role in obtaining proper seal aesthetics and integrity. This can ultimately enable the selection of robust packaging components that provide an adequate range of manufacturing conditions without cosmetic defects. A failure to do this could result in high rejects during drug product visual inspection culminating in low batch yield, high costs or could pose harm to patients if suitable CCI is not achieved.LAY ABSTRACT: One common container closure system for parenteral drug products includes a glass vial, rubber stopper, and aluminum crimp seal. The capping process, in which the elastomeric closure is compressed against the vial by means of an aluminum crimp seal, is key to ensuring an optimal seal from both an aesthetic and CCI perspective. Ensuring a robust capping process must include a deep and necessary understanding of the interconnection between the selected components, desired aesthetics of the seal, stopper compression, residual seal force, and CCI; the way in which the capper is configured (sealing parameters) will play a part in addition to the "style" used in manufacturing. Previous published studies have focused on capping process controls to only ensure CCI. Here, we present a useful methodology for selecting appropriate components and capping process parameters using a scaled-down approach to achieve elegant seal quality and CCI simultaneously. Dimensional analysis and capping design of experiments (DOEs) were conducted on lab-scale equipment that was representative of commercial configurations. The seals made from these studies were analyzed using residual seal force, helium leak, and dye ingress methods. The results and their implications were discussed with regard to the operating principle of the rail-type capping machine.

Assessment of portal image resolution improvement using an external aluminum target and polystyrene electron filter.

BACKGROUND: In this study, an external 8 mm thick aluminum target was installed on the upper accessory tray mount of a medical linear accelerator head. The purpose of this study was to determine the effects of the external aluminum target beam (Al-target beam) on the portal image quality by analyzing the spatial and contrast resolutions. In addition, the image resolutions with the Al-target beams were compared with those of conventional 6 megavoltage (MV) images. METHODS: The optimized Al-target beam was calculated using Monte Carlo simulations. To validate the simulations, the percentage depth dose and lateral profiles were measured and compared with the modeled dose distributions. A PTW resolution phantom was used for imaging to assess the image resolution. The spatial resolution was quantified by determining the modulation transfer function. The contrast resolution was determined by a fine contrast difference between the 27 measurement areas. The spatial and contrast resolutions were compared with the those of conventional portal images. RESULTS: The measured and calculated percentage depth dose of the Al-target beam were consistent within 1.6%. The correspondence of measured and modelled profiles was evaluated by gamma analysis (3%, 3 mm) and all gamma values inside the field were less than one. The critical spatial frequencies (f50) of the images obtained with the Al-target beam and conventional imaging beam were 0.745 lp/mm and 0.451 lp/mm, respectively. The limiting spatial frequencies (f10) for the Al-target beam image and the conventional portal image were 2.39 lp/mm and 1.82 lp/mm, respectively. The Al-target beam resolved the smaller and lower contrast objects better than that of the MV photon beam. CONCLUSION: The Al-target beams generated by the simple target installation method provided better spatial and contrast resolutions than those of the conventional 6 MV imaging beam.

Evaluation on the stabilization of Zn/Ni/Cu in spinel forms: Low-cost red mud as an effective precursor.

Red mud, which is from the aluminum industry, is a potentially under-utilized resource. Technological processes for using low-cost red mud as an alternative precursor for detoxifying metal pollutants urgently need to be developed. In this study, we systematically investigated the feasibility of using red mud to detoxify metal-containing wastes (e.g., fly ash) via the formation of preferable crystalline phases. To understand the mechanism of metal detoxification by red mud, CuO, NiO, and ZnO were blended with red mud at different weight ratios and the mixtures were then subjected to ceramic-sintering. After sintering, the X-ray diffraction results revealed that all of the metals (i.e., Cu, Ni, and Zn) were able to be crystallographically incorporated into spinel lattices. Sintering the red mud at 1100 °C for 3 h effectively converted the metals into spinels. The mixing weight ratios strongly affected the efficiency of the metal incorporation. The red mud was able to incorporate 15 wt% of metal oxides. The incorporation mechanisms mainly occurred between the metal oxide(s) and hematite. Modified TCLP tests were conducted to further evaluate the metal stabilization performance of the red mud, which demonstrated the leachabilities of ZnO and the sintered red mud + ZnO product. The concentration of leached metal was substantially reduced after the incorporation process, thus demonstrating that red mud can be successfully used to detoxify metals. The results of this study reveal that waste red mud can be feasibly reused as a promising waste-to-resource strategy for stabilizing heavy metal wastes.

SHAPE ESTIMATION OF BOWTIE FILTERS BASED ON THE LUMINESCENCE FROM POLYETHYLENE TEREPHTHALATE RESIN BY X-RAY IRRADIATION.

In this study, we devised a novel method estimating the bowtie filter shapes by imaging luminescence from a polyethylene terephthalate (PET) resin with X-ray irradiation in a computed tomography (CT) scanner. The luminescence distribution of the PET resin corresponding to the thickness of bowtie filter was imaged using a charge-coupled device camera. On the assumption that the material of bowtie filter is aluminium (Al), the shape of bowtie filters was estimated from the correlation between Al attenuation curves and the angular-dependent luminance attenuation profiles according to the thickness of bowtie filters. Dose simulations based on the estimated bowtie filter shapes were performed using head and body PMMA phantoms with 16 and 32 cm in diameter. The simulated values of head and body weighted CT dose index (CTDIw) based on bowtie filter shape by the luminescence imaging method agreed within ~9% with the measured values by a dosemeter.

A Preliminary Investigation of Naturally Occurring Aluminum in Grains, Vegetables, and Fruits from Some Areas of China and Dietary Intake Assessment.

An investigation of the naturally occurring aluminum contents in grains, fruits and vegetables locally planted in some areas of China was conducted, and the aluminum dietary intake from the investigated food was estimated. A total of 2,469 samples were collected during 2013 to 2014 and tested for aluminum content using ICP-MS method. The results showed that although 77.6% of the samples contained aluminum less than 5 mg/kg, significant variations of aluminum contents were observed in different food groups. Generally, the aluminum contents were found to be relatively high in dried grains and fresh vegetables, and low in fresh fruits. The mean value of aluminum contents in grains was 6.3 mg/kg, with wheat being the highest, followed by soybean and corn. The fresh vegetables had an average aluminum content of 4.7 mg/kg, with leafy vegetables being the highest, followed by bulb and stem vegetables. Most varieties of fresh fruits were low in aluminum, with the mean of 1.3 mg/kg. Based on the food consumption data from the China National Nutrient and Health Survey, the average weekly dietary intake of naturally occurring aluminum from the investigated foods was estimated to be 0.62 mg/kg bw for the general population and 0.55 to 1.00 mg/kg bw for different age groups. Grains and vegetables were the main contributors to the overall intake. Evaluated against the provisional tolerable weekly intake (PTWI) of 2 mg/kg bw, the dietary naturally occurring aluminum intake from the investigated foods was considered to be no safety concern.

Recovery of mtDNA from unfired metallic ammunition components with an assessment of sequence profile quality and DNA damage through MPS analysis.

Recovery of suitable amounts of quality DNA from copper and brass surfaces, like those encountered in ammunition, has been a challenge for the forensic community. The ability of copper ions to rapidly facilitate oxidative damage leading to fragmentation of DNA significantly reduces the pool of templates for PCR amplification. We compared two methods for recovering mitochondrial (mt) DNA from the surface of unfired copper projectiles, brass casings, and aluminum casings, and found that using a cotton swab moistened with 0.5M EDTA was the favored approach, especially when the metallic surface was etched. Degradation was significantly higher for DNA samples recovered from copper and brass surfaces, when compared to aluminum. Massively parallel sequencing (MPS) of the control region, using the PowerSeq™ CRM Nested System kit and the Illumina MiSeq instrument, produced full haplotypes for aluminum samples regardless of the method used to deposit or collect DNA, while less than 60% of the copper and brass samples produced partial or full profile information. Touch DNA collected from copper and brass samples produced higher rates of partial or full MPS profile information (∼88-96%), while collection with 0.5M EDTA produced better results than when collection was performed with water; average of ∼70% versus ∼47%. While MPS data was not impacted by noise in the sequencing process, a higher than expected rate of noise was observed, potentially due to an increase in low-level damage lesions. Noise patterns were strikingly different when compared to control data, suggesting that noisy sites may be predictable when testing samples with high levels of oxidative damage. Library preparation was a poor predictor of MPS data quality, as a large percentage of reads did not align with the reference genome. This may impact the number of samples that can be run when a deep-coverage MPS approach is being considered for analysis of mtDNA heteroplasmy. Overall, when applying an MPS approach to the analysis of mtDNA recovered from ammunition, results are expected from touch DNA, will be limited for copper and brass components when the DNA is exposed to an aqueous environment, and DNA degradation will be accelerated when DNA comes in contact with copper or brass surfaces. Practitioners should consider collecting DNA from metallic surfaces with 0.5M EDTA, as this will maximize yield and mitigate degradation. The results of this study directly impact MPS analysis of minor mtDNA sequence variants from metallic surfaces, and are particularly relevant to forensic investigations.

Assessment on the effects of aluminum-modified clay in inactivating internal phosphorus in deep eutrophic reservoirs.

Aluminum-salt inactivating agents are extensively applied to the restoration of lakes polluted by internal phosphorus (hereinafter referred to as "P"). However, there is a lack of micromechanism information regarding the sediment P cycle and its interactions with aluminum salts, which has restricted the engineering applications of aluminum salts. In this study, a sediment core incubation system was used to simulate the influence of aerobic and anaerobic conditions on the effectiveness and stability of aluminum-modified clay (AMC). This study also investigated the millimeter-scale dynamics of P across the sediment-water interface (SWI) using the HR-Peeper and DGT techniques. According to the results, sediment P release mainly occurred under anaerobic conditions. When the incubation system was in an anaerobic state, AMC effectively reduced the internal-P loading. In pore water, there was a positive correlation between soluble Fe and SRP, suggesting that the reductive dissolution of Fe-P constituted the main mechanism of sediment P release. After with dosing AMC, the concentrations of SRP and labile P in the capping layer both dropped abruptly to low levels and the content of Al-P in surface sediments rose, suggesting that AMC had strongly adsorbed phosphates, formed inert Al-P and blocked the phosphate exchange between pore water and overlying water. This study elaborated on the micromechanism of the control of sediment internal P input by AMC and revealed that Al-P precipitation constituted the main mechanism of the inhibition of sediment P release by aluminum-salt inactivating agents. The research findings have a great significance for guiding field applications of aluminum-salt inactivating agents.

Assessment the activity of magnetic KOH/Fe3O4@Al2O3 core-shell nanocatalyst in transesterification reaction: effect of Fe/Al ratio on structural and performance.

Recently, biodiesel production using heterogeneous catalysts has been of great concern. However, simple separation of these catalysts from product mixtures is a problem of the process. In this study, series of magnetic KOH/Fe3O4@Al2O3 core-shell nanocatalysts were synthesized via the incipient wetness impregnation method and the effect of weight ratio of Fe3O4-to-Al2O3 (0.15-0.35) on the catalytic performance was assessed. The samples were characterized by XRD, FTIR, BET-BJH, VSM, SEM, TEM, and EDX analyses and their basicity was measured by the Hammett indicator method. The results revealed that although the magnetic KOH/Fe3O4@Al2O3 nanocatalyst with 25 wt% of Fe3O4 showed less activity as compared to those with 15 wt% of Fe3O4, it exhibited higher surface area and appropriate magnetic properties. The sample presented superparamagnetic properties with the magnetic strength of 1.25 emu/g that was simply recovered by using an external magnetic field. The nanocatalyst converted 98.8% of canola oil to biodiesel under reflux condition at the best operational conditions of 12 M ratio of methanol/oil, 4 wt% of catalyst and 6 h of reaction time. Moreover, the nanocatalyst showed high reusability such that it was reused several times without appreciable loss of its catalytic activity.

Simple and inexpensive micromachined aluminum microfluidic devices for acoustic focusing of particles and cells.

We introduce a new method to construct microfluidic devices especially useful for bulk acoustic wave (BAW)-based manipulation of cells and microparticles. To obtain efficient acoustic focusing, BAW devices require materials that have high acoustic impedance mismatch relative to the medium in which the cells/microparticles are suspended and materials with a high-quality factor. To date, silicon and glass have been the materials of choice for BAW-based acoustofluidic channel fabrication. Silicon- and glass-based fabrication is typically performed in clean room facilities, generates hazardous waste, and can take several hours to complete the microfabrication. To address some of the drawbacks in fabricating conventional BAW devices, we explored a new approach by micromachining microfluidic channels in aluminum substrates. Additionally, we demonstrate plasma bonding of poly(dimethylsiloxane) (PDMS) onto micromachined aluminum substrates. Our goal was to achieve an approach that is both low cost and effective in BAW applications. To this end, we micromachined aluminum 6061 plates and enclosed the systems with a thin PDMS cover layer. These aluminum/PDMS hybrid microfluidic devices use inexpensive materials and are simply constructed outside a clean room environment. Moreover, these devices demonstrate effectiveness in BAW applications as demonstrated by efficient acoustic focusing of polystyrene microspheres, bovine red blood cells, and Jurkat cells and the generation of multiple focused streams in flow-through systems. Graphical abstract The aluminum acoustofluidic device and the generation of multinode focusing of particles.

A simple and economical spectrofluorimetric alternative for Al routine analysis in seafood.

A simple and economical spectrofluorimetric alternative for aluminium determination in bivalve mollusks based on the fluorescent blue-green colour complex between Al(III) and salicylaldehyde picolinoylhydrazone (SAPH) has been studied. The factors that are most likely to affect were optimized with a Box-Behnken design. Optimum conditions were: pH 6.6, 0.9 mol L-1 acetic acid/acetate buffer, 3.0 mmol L-1 SAPH, and 50% ethanol. Detection and quantitation limits were found to be 2.7 µg L-1 and 9.1 µg L-1, respectively. The upper limit of application was assessed through the limit of linearity which was set as 300 µg L-1. Intra-day repeatability and inter-day repeatability were evaluated showing an excellent precision for the fluorescence method (both < 5%). The method was sensitive enough for the satisfactory determination of aluminium in several bivalve mollusk samples both fresh and canned seafood. The results showed that commercial fresh wild products presented the smallest Al concentration (6-27 mg per 100 g dry weight), while bivalves preserved in cans the concentration was considerably higher (75 mg per 100 g dry weight). Thus, differences between Al concentration related to processing were identified. The study shows a simple, cost-effective and reliable tool for routine aluminium determination in seafood for food quality control.