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[Objectives] This study was conducted to determine the contents of such five heavy metals as lead ( Pb), cadmium ( Cd), arsenic (As), mercury ( Hg) and copper (Cu) and the contents of nine kinds of organochlorine pesticide residues including total BHC ( o:-BHC, (3-BHC, -y-BHC, o-BHC) and total DDT (pp' -DDE, pp'-DDD, op'-DDT, pp' -DDT) and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas. [Methods] The five heavy metals were determined in accordance with the second method of general rule 2341, the inductively coupled plasma mass spectrometry method, in part 4 of the 2020 edition of Chinese Pharmacopoeia; and the nine organochlorines were determined in accordance with the first method of general rule 2341, organochlorine pesticide residue determination method (chromatography), in part 4 of the 2020 edition of Chinese Pharmacopoeia. [ Results] In the Herba Polygoni Chinensis from 13 origins, the lead contents were in the range of 0. 50 - 3. 28 mg/kg; the cadmium contents were in the range of 0. 06 -4. 21 mg/kg; the arsenic contents were in the range of 0. 16 - 6. 9 mg/kg; the copper contents were in the range of 10. 5 -45. 1 mg/kg ; the mercury contents were in the range of 0. 00 - 0.003 mg/ kg; and the nine organochlorines including the total benzene hexachloride (o:-BHC, (3-BHC, -y-BHC, o-BHC), total DDT (pp'-DDE, pp'-DDD, op'DDT, pp' -DDT) and pentachloronitrobenzene were all not detected. Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia, the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards, the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard, and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard. [ Conclusiono;] This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine. [ABSTRACT FROM AUTHOR]

The study of lube oil is useful in scheduled maintenance activity, determining the oil replacement time for engines, to increase the engine life and ensure the maximum performance. Investigation of engine oil can reduce maintenance cost and promises higher design efficiency. Experiments were carried out on a mono cylinder compression ignition engine fueled with diesel-ethanol blended, which is operated at a constant rated speed of 1500 rpm for 100 hours. The lube oil samples were subjected to wear metal tests, chemical and physical tests. The quantity of wear metal in the engine oil was observed using the atomic absorption spectrometer. The total base number and total acid number were measured by the titration method according to ASTM code ASTM D6654 and ASTM2896, respectively. The viscosity was determined using the Stab Viscometer, SVM3000, by the ASTM D445 method at 40oC temperature. Iron and copper concertation was increased with an increase in usage time. However, TBN decreased, and TAN increased with the usage time. Viscosity and density decrease with the increase in usage time. The lube oil shows that the engine can be operated for an extended time with the same lube oil since all the measured parameters are within the limit. [ABSTRACT FROM AUTHOR]

A proposed method for preventing corrosion in molten fluoride salts is adding certain reducing impurities that can control the oxidizing impurities. The effectiveness of many potential reducing impurities in preventing corrosion and their effects on mechanical properties of structural materials have not been studied. This work studies the effectiveness of six different reducing impurities on preventing corrosion of Hastelloy N and SS316H in molten LiF-NaF-KF (FLiNaK) at 700 °C. Our results indicate that addition of reducing metals can be effective in controlling the corrosion of alloys depending on the testing conditions but may affect the mechanical behavior of SS316H. • Active metals are effective at corrosion control in molten fluoride salts. • The effectiveness of active metals depends on the testing conditions. • Some active metals form intermetallics affecting the tensile behavior of alloys. • Addition of Li and K lead to liquid metal embrittlement of SS316H in FLiNaK salt. • The addition of Zr, Hf, & V led to corrosion prevention of SS316H in tested salts. [ABSTRACT FROM AUTHOR]

This research was performed to assess the influence of Cd and Cr metals on growth, pigments, antioxidant, and genomic stability of Oryza sativa indica and Oryza sativa japonica were investigated under hydroponic conditions. The results revealed that significant metal influence on test crop growth, pigment content, metal stress balancing antioxidant activity in a dose dependent manner. Since, while at elevated (500 ppm) concentration of Cd as well as Cr metals the pigment (total chlorophyll, chlorophyll a , b and carotenoids) level was reduced than control; however antioxidant activity (total antioxidant, H 2 O 2 , and NO) was considerably improved as protective mechanisms to combat the metal toxicity and support the plant growth. Furthermore, the test crops under typical hydroponic medium (loaded with Cd and Cr as 200, 300, 400, and 500 ppm) growth conditions, effectively absorb the metals from medium and accumulated in the root and least quantity was translocated to the shoot of this test crops. Furthermore, typical RAPD analysis with 10 universal primers demonstrated that the genomic DNA of the test crops was adaptable to develop metal resistance and ensure crop growth under increased concentrations (500 ppm) of tested heavy metals. These findings suggest that these edible crops have the ability to accumulate Cd along with Cr metals, and additionally that their genetic systems have the ability to adapt to metal-stressed environments. [Display omitted] • O. sativa indica & O. sativa japonica metal absorption & genetic evaluation studied. • O. sativa crop cell lines possess considerable Cd and Cr metal absorption. • The test crops showed notable antioxidant activities against the tested metals. • Both crops demonstrated active metal accumulation in root than shoot. • The GTS and DNA polymorphism were found as dose dependent in test crops. [ABSTRACT FROM AUTHOR]

Integrated experimental–numerical testing on bulk metal alloys with fine, complex microstructures is known to be highly challenging, since measurements are restricted to the sample surface, thereby failing to capture the effects of the 3D subsurface microstructure. Consequently, a quantitative comparison of deformation fields between experiments and simulations is hardly possible. To overcome this, we propose a novel 'quasi-2D' integrated experimental–numerical testing methodology that hinges on the fabrication of μ m -thin specimens with practically through-thickness microstructures over large regions of > 100 μ m. The specimens are fully characterized from both surfaces and tested in-situ to retrieve microstructure-resolved deformation fields. Simultaneously, the full microstructure is discretized in 3D and simulated. This allows for a detailed, one-to-one quantitative comparison of deformation fields between experiments and simulations, with negligible uncertainty in the subsurface microstructure. Consequently, a degree of agreement between experiments and simulations is attained which we believe to be unprecedented at this scale. We demonstrate the capabilities of the framework on polycrystalline ferritic steel and dual-phase ferritic–martensitic steel specimens. At the mesoscale, the methodology enables quantitative comparisons of the interaction between multiple grains, while, at the microscale, it enables advancement of numerical models by direct confrontation with detailed experimental observations. Specifically, it is revealed that the individual slip system activity maps, identified with SSLIP, near a grain boundary can only be reasonably predicted by enhancing the adopted crystal plasticity simulations with a discrete slip plane model. Additionally, the experimentally observed strong anisotropic plasticity of martensite can only be captured with a substructure-enriched crystal plasticity model. [Display omitted] [ABSTRACT FROM AUTHOR]

We report the anti‐breast cancer stem cell (CSC) properties of a series of Group 10‐bis(azadiphosphine) complexes 1–3 under exclusively three‐dimensional cell culture conditions. The breast CSC mammosphere potency of 1–3 is dependent on the Group 10 metal present, increasing in the following order: 1 (nickel complex) <2 (palladium complex) <3 (platinum complex). Notably, 3 reduces the formation and size of mammospheres to a greater extent than salinomycin, an established CSC‐active compound, or any reported anti‐CSC metal complex tested under similar conditions. Mechanistic studies suggest that the most effective complexes 2 and 3 readily penetrate CSC mammospheres, enter CSC nuclei, induce genomic DNA damage, and trigger caspase‐dependent apoptosis. To the best of our knowledge, this is the first study to systematically probe the anti‐CSC activity of a series of structurally related Group 10 complexes and to be conducted entirely using three‐dimensional CSC culture conditions. [ABSTRACT FROM AUTHOR]

The detection of water pollutants employing organic field-effect transistor (OFET) sensor requires a stable performance in an aqueous media. It is an essential condition of any sensor to present reliable measurements. Some organic-conducting polymers deteriorate almost immediately in the presence of an aqueous medium. However, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has proven its stability in both air and aqueous mediums. Nevertheless, due to inadequate structural and chemical properties of the PEDOT:PSS, it persists major obstacles and inhibits its performance in practical applications. These shortcomings can be overcome with the combination of carbon nanomaterials. Therefore, the present study deals with the effect of inclusion of reduced graphene oxide (rGO) into PEDOT:PSS, and it resulted in the enhancement of structural, morphological, and electrical properties of the PEDOT:PSS/rGO nanocomposite. The organic field-effect transistor (OFET) was fabricated with PEDOT:PSS/rGO nanocomposite to detect heavy-metal ions. This makes a highly sensitive and selective sensor platform for detecting Hg2+ in the linear concentration range of 1–60 nM. The presented OFET sensor manifests high sensitivity and selectivity to Hg2+ with a low detection limit of 2.4 nM. The variety of metal ions tested, i.e., Hg2+, Cd2+, Pb2+, Cu2+, Zn2+, Na+, and Fe3+, to investigate the selectivity. The sensor exhibits stable performance in an aqueous medium for the detection of Hg2+ in the presence of DI water. Moreover, the OFET sensor responded within 2–3 s after incubation of Hg2+ ions' solution. [ABSTRACT FROM AUTHOR]

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Stormwater harvesting and reuse is an attractive option to lower the demand placed on other sources of water supply. However, it contains a wide range of pollutants that need to be removed before it can be reused or even discharged to the waterways and receiving waters. An experimental protocol to estimate the efficiency of a soil-based-filter medium for the treatment of stormwater pollutants from 1 to 3 years rainfall experienced in the field was developed using a laboratory column-set-up over short-term duration. The filter removed substantial amounts of PO4-P and NH4-N for up to 8 h at a flow velocity of 100 mm/h which is a 1-year time-equivalent of rainfall at a locality in Sydney, Australia. An addition of 10% zeolite to the soil-based filter extended the column saturation period to 24 h. The breakthrough data for PO4-P and NH4-N were satisfactorily described by the Thomas model. The majority of the nine heavy metals tested were removed by more than 50% for up to 4 h in the soil-based filter. This level of removal increased to 16 h when 10% zeolite was added to the filter. The column with the soil-based filter + 10% zeolite had higher affinity for Pb, Cu, Zn, and As than Ni, with Pb having the highest percentage removal. Soil-based filter + 10% zeolite removed considerable amounts of 3 polycyclic aromatic hydrocarbons (PAHs) (30–50%), while soil-based filter + 10% zeolite + 0.3% granular activated carbon removed 65 to > 99% of the PAHs at 24-h operation. [ABSTRACT FROM AUTHOR]

The materials corrosion test (MaCoTe) is a long‐term, multinational in situ corrosion experiment setup at the Grimsel Test Site, Switzerland. The experiment has been operating since 2014 with a focus on the corrosion behaviour of container materials for the disposal of high‐level waste and spent nuclear fuel under conditions representing a granitic deep geological repository. The experiment consists of eight modules containing metal coupons and bentonite. Two of the modules, each with a different bentonite density, have been retrieved after 394 days of exposure and have been analysed using a range of techniques aimed at studying the corrosion behaviour of the metals and the mineralogical evolution of the bentonite. Weight loss measurements show that carbon steel had a relatively low average corrosion rate (~2 µm year−1). Much lower average corrosion rates were measured for the various types of copper (0.13–0.32 µm year−1). No detectable corrosion was measured on stainless steel coupons. To date, no significant differences were observed in the corrosion behaviour and rate of the test metals in bentonite with different dry densities. [ABSTRACT FROM AUTHOR]

To investigate the feasibility of the application of new high-performance polyamide 1012 (PA1012) filaments in the textile field, the friction properties of PA1012 under different processing conditions were tested and compared with polyamide 6(PA 6)filaments. The tensile properties of the above polyamide fibers were tested and analyzed by SEM. The results show that as the draft ratio increases from 1.3 to 2.7, the static friction coefficient of PA1012 fibers decreases first and then increases, and the initial modulus of the fibers gradually increases, with the maximum value of 3.72 cN/dlex. On rubber roller testing, the static friction coefficient of the PA1012 fiber reaches the maximum value of 0.44 with the spin-draw ratio of 2.7, and the minimum value of 0.28 with the spin-draw ratio of 2.1. The dynamic friction coefficient of the PA1012 fiber reaches the maximum value of 0.25 with the spin-draw ratio of 2.7, and the minimum value of 0.22 with the spin-draw ratio of 1.7. On metal roller testing, the static friction coefficient of the PA1012 fiber reaches the maximum value of 0.53 with the spin-draw ratio of 1.3, and the minimum value of 0.22 with the spin-draw ratio of 2.1. After draw-texturing processing, the static friction coefficient and dynamic friction coefficient increase by 26.2% and 22.7% respectively, but the initial modulus decreases by 24.1%. The static friction coefficient and the dynamic friction coefficient of PA1012 fiber is 13.3% and 7.1%, higher than that of PA6 respectively, but the initial modulus of PA1012 fiber is 19.1% lower than that of PA6. It is suggested that the draft multiple of PA1012 fiber should be controlled within 1.7~2.1 in actual production. [ABSTRACT FROM AUTHOR]

In this study, we report for the first time a novel type of sorbent that can be used for mercury adsorption from the air-based off-gasses—vermiculite impregnated with alkali polysulfides and thiosulfates. In contrast to other sorbents, vermiculite exhibits superior thermal stability in air and low adsorption capacity for organic vapors. This allows for a more favorable design of the soil remediation unit—direct coupling of thermal desorber with catalytic oxidizer using air as a carrier gas. In the bench-scale test at 180 °C, the sulfur/vermiculite sorbent exhibited significantly higher efficiency for the adsorption of mercury vapor from the off-gasses than the commercial sulfur/activated carbon sorbent at its highest operating temperature (120 °C). The average mercury concentration in the adsorber off-gas decreased from 1.634 mg/m3 for the sulfur/activated carbon to 0.008 mg/m3 achieved with impregnated vermiculite. The total concentration of organic compounds in the soil after thermal desorption was below the detection limit of the employed analytical method. [ABSTRACT FROM AUTHOR]

This study evaluated the toxic effects of inorganic mercury (Hg) in pregnant and lactating rats, as well as the possible protective effect of zinc (Zn) and N-acetylcysteine (NAC). Pregnant and lactating rats were pre-treated with ZnCl2 (27 mg/kg) and/or NAC (5 mg/kg) and after 24 h, they were exposed to HgCl2 (10 mg/kg). Animals were sacrificed 24 h after Hg exposure, and biochemical tests and metal determination were performed. Regarding pregnant rats, Hg exposure caused kidney, blood, and placenta δ-aminolevulinic acid dehydratase (δ-ALA-D) activity inhibition, and the pre-treatments showed a tendency of protection. Moreover, all the animals exposed to Hg presented high Hg levels in the kidney, liver, and placenta when compared with control group. Pregnant rats pre-exposed to Zn (Zn-Hg and Zn/NAC-Hg groups) presented an increase in hepatic metallothionein levels. Therefore, lactating rats exposed to Hg presented renal and blood δ-ALA-D inhibition; the pre-treatments showed a tendency to prevent the renal δ-ALA-D inhibition and prevented the blood δ-ALA-D inhibition caused by Hg. Lactating rats exposed to Hg presented high Hg levels in the kidney and liver. These results showed that 10 mg/kg of HgCl2 causes biochemistry alterations in pregnant and lactating rats, and Zn and NAC present promising results against these damages. [ABSTRACT FROM AUTHOR]

Control of elemental impurities in the drug products evolved from the generic visual testing of heavy metals as their sulfides to specific elements of toxicological concern in the final drug products by instrumental analysis. The International Council for Harmonisation (ICH) Q3D (R1) guideline for elemental impurities describes a risk-based approach to identify, assess, and control the potential elemental impurities in drug products within the established permitted daily exposures (PDE). Challenges to this approach include how to assess the risks associated with contributing sources such as utilities, manufacturing equipment, container-closure systems, and excipients. Defining at what stage of development that such assessment should be performed to identify the risk levels can be equally challenging. In this article, we report an approach to control elemental impurities of toxicological concern, compliant to the Q3D (R1) guideline, and a summary of results obtained on multiple protein therapeutic products. This approach follows the elements of Process Validation, i.e., Design, Qualification, and Continuous Verification. The design includes the selection of excipients and their suppliers that meet the Option 1 requirement of Q3D (R1). It also comprises the selection of manufacturing equipment, container-closure systems, and utilities. The qualification includes the testing of the potential sources of elemental impurities, i.e., excipients, utilities, and leachables/extractables from the manufacturing equipment and container-closure systems. The Continuous Verification comes from the testing of representative batches at the initiation of stability studies of clinical or commercial drug product batches and at the end of shelf-life expiry of the drug product, and when changes are made to the manufacturing equipment, sources of excipients and container closure systems, and any formulation changes. Our experience shows that the risk associated with the impurity levels of the ten elements of toxicological concern in the therapeutic protein drug products, parenterally administered, is well below the control threshold (30% PDE) in the drug product recommended by the ICH Guideline. Although our focus is on the injectable therapeutic proteins, this approach can be applied to the products administered via other routes as well. [ABSTRACT FROM AUTHOR]

Based on the developed methods of hysteretic interference, we produced the calculated dependences of the electric voltage across a magnetic field transducer on the x-coordinate. A magnetic carrier with an arctangent characteristic was exposed to a series of one, two, three, four, five, and fifteen bipolar pulses of linear-inductor magnetic field. An algorithm is presented for the sequence of changes in the total intensity of the magnetic field pulses on the aluminum plate surface that ensures the same amplitude of hysteretic electric-voltage oscillations and allows one to obtain a linear difference dependence for wedge-shaped and flat aluminum samples. The results obtained make it possible to improve the accuracy and efficiency of object thickness gaging and testing for thickness variation in the given directions, as well as for defects in the object. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) in the sediments of Jianhu Lake were measured by an inductively coupled plasma-optical emission spectrometer (ICP-OES) to determine their spatial distribution characteristics and ecological risks. The results showed that the average concentrations of Cd, Cr, Cu, Pb and Zn in surface sediments (0-5 cm) were 0.41±0.34, 143.89±90.07, 46.14±30.08, 56.38±45.71, and 146.52±96.50 mg/kg, while those in core sediments (0-75 cm) were 0.51±0.44, 228.35±174.52, 89.94±74.63, 74.92±65.69, and 208.89±171.55 mg/kg, respectively. The total concentrations of heavy metals were highest in the western area of Jianhu Lake, and were higher in the bottom layer (70-75 cm) than in the surface layer (0-5 cm) in the entire Jianhu Lake region. The potential ecological risks of Cd in sediments were greatest, and the comprehensive potential ecological risks of the five tested heavy metals in sediments were highest in the western area of Jianhu Lake. Using the geoaccumulation index (Igeo), we found that pollution in sediments due to Cr was the most serious of all the heavy metals, and the degree of pollution due to these five heavy metals in each area varied greatly in Jianhu Lake. In addition, we found that the short-term release contribution of Pb and Zn was large, while both the short- and long-term release contributions of Cr were small. [ABSTRACT FROM AUTHOR]

• New shear specimen designed for dynamic tests using SHPB device. • Deformation behavior of 304 ASS investigated over a wide range of strain rates from 0.001 s−1 to 38700 s−1. • Ultra-high strain rates above 104 s−1 achieved. • Simple shear stress state with low stress triaxiality and Lode angle parameter obtained. • Correction coefficient method for accurate shear stress-shear strain relations measurement. This paper describes a new single-shear specimen (SSS) and method to characterize the dynamic shear behavior of bulk metals using a traditional Split Hopkinson Pressure Bar (SHPB). By this method, the shear behavior of materials can be tested conveniently over a wide range of strain rates within 105 s−1. This technique was applied to a 304 austenitic stainless steel (ASS) under shear strain rates from 0.001 s−1 to 38700 s−1 at room temperature. Based on finite element (FE) simulations, it was found that the deformation of the specimen shear zone was dominated by shear stress/strain components. Stress state parameters represented by stress triaxiality η and Lode angle parameter θ - were found very close to zero, indicating a deformation mode of simple shear. Besides, an obvious gap existed between the local deformation behavior in the specimen shear zone and the macroscopic stress-strain relations measured by the strain gauges on the SHPB bars. A correction coefficient method was adopted to extract the real shear behavior from the experimentally obtained force-displacement data. Through comparisons between the tested and simulated stress-strain curves, a good agreement was obtained. [ABSTRACT FROM AUTHOR]

The capacity of Lemna minor to remediate toxic heavy metals from wastewater is reasonably well documented. In view of the pivotal role of this species in the environmental clean-up, here we evaluated the bioaccumulation potential of L. minor for cadmium (Cd), lead (Pb), and nickel (Ni) through a controlled experiment. L. minor tolerated the metals Cd, Ni, and Pb up to 0.5, 5, and 8 mg/L, respectively, and beyond these concentrations the toxicity symptoms appeared. Bio-concentration factor varied at different concentrations of heavy metals tested. Overall, L. minor showed good phytoremediation potential for all the three tested heavy metals (Cd, Ni, and Pb), though in relative terms it was more effective in extracting Ni and Cd, as compared to Pb, both in single and mixed concentrations. In view of the growing pollution in Kashmir Himalayan aquatic habitats the phytoremediation by invasive species such as L. minor promises to be one of the best choices than other native plants for cleaning up of polluted soils/water because of its fast growth rate, high abundance, easy handling, and wide distribution in Kashmir Himalayan aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl and polyfluoroalkyl substances (PFAS), widely used in many commercial and military products, have been notorious due to their environmental persistence. Even radical-based advanced oxidation technologies have been reported to be less effective for decomposition of PFAS, particularly perfluoroalkyl ones, while commonly requiring energy-intensive extreme conditions and tools such as ultraviolet, ultrasound, microwave, electron beam, and high temperatures. Herein, for the first time, the potential of a modified Fenton system, i.e., homogeneous persulfate (PS) conjugated with silver (Ag+), to decompose PFAS under ambient conditions is communicated. Among many combinations of common oxidants and transition metals tested, only the PS/Ag pair showed significant reactivity at 20°C exclusively toward carboxylic PFAS including perfluorooctanoic acid, resulting in evolution of fluoride ion release and reaction by-product formation. Although sulfonic PFAS still remain challenging, and follow-up assignments are raised to investigate in-depth mechanisms and examine other oxidant and metal pairs, this study offers one step closer to establishing an energy-independent and more practical treatment system for PFAS. [ABSTRACT FROM AUTHOR]

Muscle tissue from three-spotted tilapia (Oreochromis andersonii) (n = 11), sharp tooth catfish (Clarias gariepinus) (n = 14) and tigerfish (Hydrocynus vittatus) (n = 12) were sampled from a market in the Zambezi region, Namibia in June 2018 and analysed for cadmium and lead. Cadmium was not detected in the three fish species. Mean lead levels in all three fish species (0.09–0.19 mg kg−1) were below the recommended safe level of 0.3 mg kg−1. Catfish had the highest mean lead concentrations, followed by tigerfish and tilapia in descending order. However, the differences in mean lead concentrations between the three fish species were not statistically significant (ANOVA, p = 0.18). These results show that the fish tested were safe for human consumption with respect to the metals tested. It is recommended that more metals and other contaminants, such as pesticides, be monitored robustly in water, sediment and fish, using the recommended protocols, in order to generate data that can be reliably used for human health risk assessments in the future. [ABSTRACT FROM AUTHOR]

A competitive enzyme-linked immunosorbent assay (ELISA) test using polyclonal rabbit antibodies for detection of Chlorpyrifos-ethyl (CPE) and its two major metabolites of degradation [3,5,6-Trichlororpyridin-2-ol (TCP) and O,O'-diethylthiophosphoric acid (DETP)], has been developed. We have first synthetized haptens of these three molecules, with 4 and 5 carbons spacer arms having carboxyl function at their ends. Haptens with 5 carbons' spacer arm have been coupled to Bovine Serum Albumin (BSA) then injected to rabbits for polyclonal antibodies production. Haptens with 4 carbons spacer arm have been coupled to Human Albumin (HAS) to be in well plates coating to perform the ELISA tests. After adjusting the ELISA parameters, we have plotted the B/B0 (%) values against the logarithm of analyst concentrations. The IC50 values and detection limits were obtained through fitting the curves. The IC50 value of CPE and TCP were 651 and 5.61 ppb, with detection limits about 2.3410−2 and 2.18 10−3 ppb, respectively. We report for the first time, ELISA system developed for DETP with IC50 of 76.5 and a detection limit of 8.81 10−3 ppb. To evaluate the potential interferences that may be encountered in environmental water samples, pH, ionic strength, humic acid and some heavy metals were tested upon IC50 of the developed ELISA systems. In addition, several pesticides as well as CPE metabolites were tested for cross reactivity study. In all cases, the interference of the CPE assay was negligible. TCP assay represented a high cross reactivity to CPE but no interference with the others compounds. For DETP, no cross reactivity with the TCP was detected, but it was higher with CPE and the others pesticides. The developed ELISA systems have been compared with HPLC technique. Both techniques gave values of the same order of CPE and TCP prepared concentrations with a better sensitivity for ELISA system. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) strains are widespread globally. Besides their virulence factors, the co-occurrence of antimicrobial and metal resistance has been reported. This study was designed to evaluate the antibiotic resistance and resistance phenotypes, investigate the occurrence of virulence factors, and detect heavy metal tolerance among MRSA strains. Antibiogram profiling was done as recommended by CLSI instructions. Resistance phenotypes were detected by D test, followed by characterization of enzymatic activities and biofilm formation assay. Antibacterial activity of different heavy metals was tested, and predictable synergistic assay was performed. Among MRSA strains collected, high resistance to ampicillin and amoxicillin/clavulanate (100%) and high susceptibility to clindamycin (70%) were obtained. Resistance phenotypes were detected as S, constitutive MLSB, inducible MLSB, and MS by percentages of 10%, 30%, 30% and 30% respectively. Virulence factors like lipolytic (50%) and hemolytic (70%) activity, and biofilm formation ability (100%) were detected. High resistance towards potassium and magnesium was observed. MTC of 500 ppm was detected for all isolates in case of cobalt and iron. In case of zinc and copper, MTC was detected as 500 ppm except for one isolate which was highly resistant, and 500 ppm for all isolates except for two isolates which were highly sensitive respectively. Magnesium in different concentrations (500 and 2000 ppm) showed synergistic activity with erythromycin and clindamycin. Results reveal high heavy metal tolerance among antibiotic resistant MRSA strains, in addition to the presence of virulence factors. Upcoming studies must be focused on the combination of sub-inhibitory concentration of different heavy metals with the available antibiotics. [ABSTRACT FROM AUTHOR]

Strain gauges are commonly used for tension tests to obtain the strain of a metal test specimen. They make contact, however, so the gauges are not applicable to every type of test specimen. That is the reason why a non-contact type measurement system is required. Nanofibrous mats, manufactured by electrospinning, have different structures and thicknesses. Displacement and strain distributions for all ranges of the specimen have never been demonstrated for nanofiber mats so far. Wrinkled nanofibrous mats of polyurethane were made and then tension-tested. The Digital Image Correlation (DIC) method was employed to measure displacement, then to calculate strain for all areas of the specimen. The DIC system consisted of a CMOS camera, control PC and operating software with a DIC algorithm: then, the Center of Gravity (COG) algorithm was used for this system. A cross-head speed of 3 mm/min was set for the tension test. The image record speed was one frame a second. In total, 400 image frames were obtained from the start, and then displacement and strain distributions were acquired for a 400 second tension test. The strain distribution from DIC system showed good agreement with the test result by a universal testing machine. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of heavy metals, such as copper, zinc, iron, cobalt, chromium, aluminium, manganese and molybdenum, on zebrafish egg hatching rate and the subsequent survival rate of the larvae. Each metal was used in the various concentrations of0.05 mg/L, 50 mg/L and 500 mg/L to detect the threshold limit of tolerance. The study's results showed significant differences in the hatching and survival rate of larvae between the control group and most of the experimental groups when adding heavy metals in various concentrations. The highest concentration (500 mg/L) of the induced heavy metals tested in this study resulted in total egg or larval mortality within 96 hr and significantly lower egg or larval life expectancy. Among the tested metals, zinc and molybdenum had the most significant impact on hatching time, in contrast to iron that did not differentiate the results from the control group. Copper, cobalt, chromium, aluminium and manganese did affect zebrafish eggs depending on their exposure concentrations, which differentiated the results from the control group. Also, the study's findings demonstrate a significant dependence of the hatched egg heart rate on the metal concentration, and in particular, higher concentrations of metals correspond to higher heart rate. Zinc, Molybdenum and copper was proved to be the most toxic heavy metals causing increased hazard rate to mortality up to 96 hr and shorter life expectancy. Finally, skeletal deformities that occasionally observed did not significantly affect the total life expectancy of the hatched eggs. [ABSTRACT FROM AUTHOR]

This work describes the procedure for determining residual surface stresses using the mechanical method and four methods of hardening samples. The urgency of the problem stated in the article is due to the fact that surface tensile stresses arising in the manufacture of highly loaded parts can significantly reduce the mechanical, resource and fatigue characteristics of products. The aim of the study was to harden samples of titanium and ironchromium-nickel alloys to improve their strength, fatigue and resource characteristics and determine residual stresses by layer-by-layer removal of the studied layers by electrochemical etching. The determination of surface residual stresses was carried out mechanically using a measuring and calculation complex during continuous etching of the metal from the test surface of the sample, which made it possible to measure the residual stresses at different depths and determine the energy of the surface stress state. Residual stresses were calculated from the deformation of the remaining part of the sample with a change in the depth of the studied layers. The hardening of the samples was carried out in four ways, namely: ultrasonic hardening; ultrasonic curing + Rosler (vibration processing); Rosler (vibration processing) + ultrasonic curing; Rosler (vibration processing) + ultrasonic hardening. The results of the study showed that the surface of the products is a weaker area than the inside. After quenching, surface compressive stresses arise for all samples of titanium and iron-chromium-nickel alloys. The preferred case of hardening is the second (ultrasonic hardening + centrifugal hardening). The presence of residual compressive stresses in the outer layers of the products increases their fatigue limit by ≈20%. The results of the work can be used to manufacture products with high mechanical, resource and fatigue characteristics. [ABSTRACT FROM AUTHOR]

The article informs that periodical's current awareness service covers British and international publications, conference proceedings and multimedia products, and presented a list compiled from publications, products and information received as a result of exchange agreements, and subscriptions. Topics include Observation, inspection and diagnostic devices at the Interpolitex 2018 exhibition; and diagnostics of resonant modes of rotor blades during resonant tests of a gas turbine engine.

Extraction of lanthanide ions with different ionic radius (La3+, Gd3+ and Lu3+) from aqueous solutions was carried out by using two synthetic saponite clays. The clays, prepared through a simple and low-cost hydrothermal approach, showed different particle size and cation-exchange capacity (CEC) and were characterized in order to evaluate the influence of their physico-chemical properties on the uptake process. Metal uptake tests, performed in pure water and simulated freshwater and seawater solutions, demonstrated that synthetic saponites have a general good sorption capacity with high lanthanide capture after a few hours of contact. The solid samples showed a higher selectivity for Lu3+, due to its small ionic radius. [ABSTRACT FROM AUTHOR]

Heavy metal contamination is a major global concern and additive toxicity resulting from the exposure to multiple heavy metal ions is more pronounced than that induced by a single metal species. Quantum dots (QDs) have demonstrated unique properties as sensing materials for heavy metal ions over the past two decades. With the rapid development and deep understanding on determination of single heavy metal ion using QD probes, this technology has been employed for sensing multiple metal ions. This review (with 97 refs.) summarizes the progress made in recent years in methods for multiplexed determination of heavy metal ions using QDs. Following an introduction into the importance of simultaneous quantitation of multiple heavy metal ions in environmentally relevant settings, the review discusses the applications of different types of QDs, i.e. chalcogenide, carbon, polymer and graphene in this field. Determination strategies based on fluorometric, colorimetric and electrochemical responses were reviewed including the testing mechanisms and differentiation between various metal ions. In addition, current state of the art sensor constructions, i.e. immobilization of QDs on solid substrate and sensor arrays have been highlighted. A concluding section describes the limitations, opportunities and future challenges of the QD probes. We also compiled a comprehensive table of currently available literature. The listed papers provided information in the following categories, i.e. type of QDs used, ligands or other components in the probe, metal ions tested, medium/substrate of the probe, transduction methods, discrimination mechanism, limit of detection (LOD) and concentration range. [ABSTRACT FROM AUTHOR]

Metal sulfide catalysts for ultra‐deep hydrodesulfurization of diesel generally lose a fraction of their catalytically active sites during reactor startup. The underlying mechanisms are discussed. A laboratory diagnostic tool consisting of three probe molecules is developed for testing metal sulfide catalysts' start‐of‐run (SOR) activity maintenance. It is found that a significant fraction of the active sites on a commercial supported catalyst are deactivated permanently, but this is not the case with a bulk metal sulfide catalyst. The SOR deactivation of the bulk catalyst is completely reversible, while that of the supported catalyst is partially reversible. The diagnostic tool may provide a basis for developing a high‐throughput approach for evaluating and enhancing catalyst SOR stability, thereby increasing plant productivity. [ABSTRACT FROM AUTHOR]

The main objective of this research is to develop a characterization method for parts fabricated in metal powder bed fusion (PBF) processes, a type of additive manufacturing (AM) process. To characterize conventionally manufactured parts, many methods and standards are available, while no comprehensive standards or methods are available for AM parts. In this paper, a mechanical property characterization method is proposed that involves statistical analysis to select sample sizes and test coupon design considerations for metal printing, printing parameters, and applicability of existing testing standards for metal PBF, in addition to several mechanical properties. As proof of concept for the proposed characterization method, material and mechanical property characterization of the metal printed (EOS M280) EOS maraging steel grade 300 material is presented along with selected sample lots and relative errors. The characterization method presented in this paper is applicable to any metal AM process. [ABSTRACT FROM AUTHOR]

Laser metal deposition (LMD) is utilized to clad the surface of a miniaturized test roll (Ø 40 mm) of tool steel. The cladding consists of two layers: a nickel alloy as intermediate layer deposited onto the surface of the steel substrate, and a metal matrix composite (MMC) as top layer consisting of spherical tungsten carbide particles embedded into the nickel alloy matrix. The thermomechanical wear behavior of the cladding is investigated on a test rig, where the test roll is pressed against an inductively heated load roll. Multiple test runs up to several hours simulating industrial loading conditions are performed. The presented testing procedure enables predicting the time‐dependent abrasive wear behavior of the cladding, in particular for hot rolling mill applications. After testing for 8 h at temperature of 650 °C and at contact pressure of approximately 1 GPa, the maximum depth of the wear mark is about 0.12 mm. Partial cracking, debonding and dissolution of the tungsten carbide particles, as well as formation of iron and chromium oxides at the surface of the wear marks occur. However, as low abrasive wear is observed, the investigated MMC may potentially be applicable for cladding rolls in steel hot rolling mills. [ABSTRACT FROM AUTHOR]

Ultrahigh-purity aluminium sheets with excellent electrical and thermal conductivity at ultralow temperature have uses in heat dissipation components in, for example, superconducting equipment. Recently, here has been a requirement for the development of methods of welding these sheets without degrading their excellent conductivity. This study focused on friction stir welding (FSW), which was conducted for 99.999 wt.% (5 N) Al thin sheets with thickness of 0.8 mm. The FSW tool rotation speed was set to 3000 rpm, and both the welding speed and tool insertion depth were varied. Decreasing welding speed suppressed the occurrence of a kissing bond on an FSW back side and increased the area of the stir zone that had ultrafine grains, although residual strain in all the joints was greater than in tungsten inert gas (TIG)-welded joints which consisted of coarse grains similar to the base metal. Fracture occurred in the base metal in tensile tests of the FSW joints except for those made at the maximum welding speed, in contrast to rupture near the fusion line of the TIG-welded joint due to blowholes. On the other hand, the residual resistivity ratio (RRR) of FSW and TIG-welded joints decreased to almost half of that of the base metal. The heat treatment at 500°C for 3 h increased the RRR of the FSW joints to almost the same value as that of the base metal. This is attributed to a significant reduction of residual strain as well as grain coarsening. In TIG-welded joint, there is an evident decrease in the RRR associated with a decrease in purity. Therefore, FSW in conjunction with post-weld heat treatment would be a better choice to achieve high conductivity at ultra-low temperatures in 5 N-Al thin sheet joints, while maintaining a high joining strength. [ABSTRACT FROM AUTHOR]

We compared inductively coupled plasma–mass spectrometry (ICP-MS) test results for the analysis of heavy metals (As, Ba, Cd, Hg, Pb, and Se) in pet foods and routine veterinary diagnostic specimens using intralaboratory and interlaboratory comparisons. Four laboratories, 1 principal laboratory and 3 collaborating laboratories, conducted instrument comparison (limit of detection [LOD], limit of quantification [LOQ], and linear dynamic range [LDR] on 24 data sets), in-house method comparison (accuracy and precision on 120 data sets), and interlaboratory comparison (reproducibility on 528 data sets using Horwitz equation analysis). Matrices tested included 2 types of pet food jerky treats (chicken and sweet potato), bovine blood, and bovine liver and kidney. The instrument comparison study confirmed that ICP-MS provided the sensitivity necessary for the analysis of all heavy metals tested at concentrations below the level of concern for routine diagnostic testing. The "in-house" method comparison samples, spiked at low (0.04 µg/g), medium (0.4 µg/g), and high (8.0 µg/g; note: the high validation level spike for mercury was 2 µg/g) concentration levels, indicated that ICP-MS can meet U.S. FDA acceptance criteria for both accuracy (90–105% recovery) and precision (< 6% coefficient of variation). The interlaboratory comparison studies showed that ICP-MS is a reproducible method for the analysis of heavy metals (HorRat value of 0.5–2.0) except for mercury in one laboratory, which used a different sample preparation method (open block rather than microwave digestion). Overall, our study showed that ICP-MS is a reproducible method for the analysis of heavy metals in spite of minor differences in methodology. [ABSTRACT FROM AUTHOR]

A ligand comprised of a macrocyclic pyridinophane core having a pendant arm containing a secondary amine group linked through a methylene spacer to a pyridyl–oxadiazole–phenyl (PyPD) fluorescent system has been prepared (L). The crystal structures of [ZnL](ClO4)2 and [CuL](ClO4)2 show that M2+ is coordinated to all the nitrogen atoms of the macrocyclic core, the secondary amine of the pendant arm and the nitrogen atom of the pyridine group of the fluorescent moiety, the latter bond being clearly weaker than the one with the pyridine of the macrocycle. Solution studies showed the formation of a highly stable Cu2+ complex with 1 : 1 stoichiometry, whereas with Zn2+ least stable complexes were formed and, given the right conditions, a [Zn3L2]6+ species was also detected, but it was not possible to isolate this species in the solid state. Following Zn2+ coordination, a strong chelation-induced enhancement of fluorescence was observed, a behaviour that was not observed with any of the other metal cations tested. [ABSTRACT FROM AUTHOR]

The post-detonation burning effect of aluminum (Al) powder plays an important role during the expansion of detonation products (DPs) of aluminized explosives (AEs). Lithium fluoride (LiF) is an inert substitute for Al, and hence, a comparison of the performance of composite explosives based on cyclotrimethylenetrinitramine (RDX), such as RDX/Al and RDX/LiF, clearly illustrates its contribution to accelerating ability due to Al oxidation. A series of metal plate tests is conducted to measure the velocity history of a metal plate driven by RDX/Al and RDX/LiF through a photonic Doppler velocimetry system with 5%, 15%, and 25% Al or LiF contents. The detonation and expansion process of the AEs is generally divided into two stages: the detonation zone (DZ) and the post-detonation zone (PDZ). In the DZ, the Al powder remains inert, while it absorbs the detonation energy from pure explosives. Therefore, the equivalent inert dilution model is established and the equivalent inert dilution coefficient of the Al powder is introduced. In the PDZ, the Al powder reacts with DPs, and the Al oxidation reaction results with a change in entropy related to the reaction degree of the Al powder. Based on the local isentropic assumption, as well as the function of the reaction degree of the Al powder, a non-isentropic model is established. The method of the non-linear characteristic line is applied to theoretically calculate the metal plate velocity based on the non-isentropic model. In addition, the theoretical results show good agreement with the metal plate test results with an acceptable error (less than 10%), indicating that the non-isentropic model can be effectively applied to analyze the accelerating ability of the AEs. [ABSTRACT FROM AUTHOR]

In this article, we present an analytical formulation based on an equivalent circuit model to support the challenging task of designing and analyzing single-ended patch sensing elements to be integrated in planar technologies. The proposed approach further allows for differentiating the permittivity values of the individual layers when sensing over dense and stratified mediums. The equivalent model of the sensing pixel is derived resorting to equivalence theorem and transmission-line theory. The relative impact of the material under test and the metal thickness of the sensing element is accurately included in the evaluation of the endpoint load of the radial transmission line, equivalent to the patch radius. This approach of representing the single-ended sensing element isolates the capacitance contributions associated with the patch radius, patch thickness, and the medium under test. The computationally fast tool is further utilized in absolute permittivity measurements using a 0.14- $\mu \text{m}$ CMOS 2-D permittivity imaging matrix prototype operating from 100 MHz to 2.9 GHz, reporting excellent agreement with theoretical values. [ABSTRACT FROM AUTHOR]

The standard scheme of several tests of the Pauli Exclusion Principle in bulk matter -- both in the experiment and in the subsequent data analysis -- has long been based on the seminal paper by E. Ramberg, G.A. Snow The ideas exposed in that paper are so simple and immediate that they have long gone unchallenged. However, while some of the underlying approximations are still valid, other parts of the article must be reconsidered. Here, we discuss some new concepts that are related to the motion of the electrons in the test metal (the "target" of the experiment) and which have been recently studied in the framework of the VIP-2 Collaboration. [ABSTRACT FROM AUTHOR]

This paper is concerned with the selection of the geometries of test specimens for bulk metal characterization tests. Simulations of characterization tests on cylindrical, notched, and shear specimens were conducted to allow for the analysis of stress state evolution during the tests and to evidence the impact of geometry on stress state. Both stress triaxiality and Lode parameter were considered for selecting representative specimens. Three choice criterions were regarded: the diversification of stress states as well as the constancy and the nearness of stress state indicators to the theoretical values along the deformation. [ABSTRACT FROM AUTHOR]

The Cambridge Structural Database (CSD) currently contains over 400 000 transition‐metal‐containing entries, however many entries still lack curated oxidation‐state assignments. Surveying and editing the remaining entries would be far too resource‐ and time‐intensive to be carried out manually. Here, a highly reliable automated workflow for oxidation‐state assignment in transition‐metal coordination complexes via CSD Python API (application programming interface) scripts is presented. The strengths and limitations of the bond‐valence sum (BVS) method are discussed and the use of complementary methods for improved assignment confidence is explored. In total, four complementary techniques have been implemented in this study. The resulting workflow overcomes the limitations of the BVS approach, widening the applicability of an automated procedure to more CSD entries. Assignments are successful for 99% of the cases where a high consensus between different methodologies is observed. Out of a total number of 54 999 unique metal atoms in a test dataset, the procedure yielded the correct oxidation state in 47 072 (86%) of cases. [ABSTRACT FROM AUTHOR]

Biaxial testing technology enables the comprehensive study of sheet-forming performance and has great potential developmental and commercial value. This work is a review of cruciform biaxial tensile testing technology, as used in actual production, and provides evidence for sheet metal forming processes to describe problems that remain to be solved and to suggest new ideas for future study. The testing apparatus including cruciform biaxial tensile testing machines, heating devices, and optical strain measurement systems are discussed. Some typical descriptions of material tests to achieve stress and strain curves, the yield loci, and limit strains relating to both ambient and high temperatures are also presented. Moreover, finite element modeling as applied to specimen design, material deformation prediction, and material model determination is investigated. Furthermore, the sample design methods and a few examples are summarized in spite of the lack of geometry standard. Future prospects are mainly focused on the establishment of specimen geometry standard, reverse modeling technique for high temperature tests, and the actual applications of biaxial tensile tests. [ABSTRACT FROM AUTHOR]

Advanced vision method of analysis of the Erichsen cupping test based on laser speckle is presented in this work. This method proved to be useful for expanding the range of information on material formability for two commonly used grades of steel sheets: DC04 and DC01. The authors present a complex methodology and experimental procedure that allows not only to determine the standard Erichsen index but also to follow the material deformation stages immediately preceding the occurrence of the crack. Accurate determination of these characteristics in the sheet metal forming would be an important application, especially for automotive industry. However, the sheet metal forming is a very complex manufacturing process and its success depends on many factors. Therefore, attention is focused in this study on better understanding of the Erichsen index in combination with the material deformation history. [ABSTRACT FROM AUTHOR]

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