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An engineered biochar was fabricated via paper mill sludge pyrolysis under CO 2 atmosphere, and its adsorption capability for As(V) and Cd(II) in aqueous solution was evaluated in a batch mode. The characterization results revealed that the biochar had the structure of complex aggregates containing solid minerals (FeO, Fe 3 O 4 and CaCO 3 ) and graphitic carbon. Adsorption studies were carried out covering various parameters including pH effect, contact time, initial concentrations, competitive ions, and desorption. The adsorption of As(V) and Cd(II) reached apparent equilibrium at 180 min, and followed the pseudo-second-order kinetics. The highest equilibrium uptakes of As(V) and Cd(II) were 22.8 and 41.6 mg g −1 , respectively. The adsorption isotherms were better described by Redlich-Peterson model. The decrease in As(V) adsorption was apparent with the increase in PO 4 3− concentration, and a similar inhibition effect was observed for Cd(II) adsorption with Ni(II) ion. The feasibility of regeneration was demonstrated through desorption by NaOH or HCl. [ABSTRACT FROM AUTHOR]

The possibility of using pyrolyzed paper as disposable working electrodes for trace metals determination is reported for the first time. A small piece of pyrolyzed paper (0.7×0.7 cm) was positioned at the bottom side of the electrochemical cell using a rubber O-ring, which defined the electrode area (0.48 cm; 0.18 cm 2 ). A large number of electrodes can be obtained from a single piece of standard dimensions (2.5 cm×7.5 cm) of paper, therefore minimizing the cost per unit. The electrochemical performance of the pyrolyzed paper was demonstrated by cyclic voltammetry, electrochemical impedance spectroscopy and by the determination of Zn, Cd, and Pb by square-wave anodic stripping voltammetry. The unmodified pyrolyzed paper showed excellent performance for Pb and Cd detection (LOD =0.19 and 0.16 ppb, respectively). In the presence of Bi 3+ (in-situ film formation), the simultaneous determination of Zn, Cd and Pb was also possible (LOD=0.26, 0.25, and 0.39 ppb, respectively). [ABSTRACT FROM AUTHOR]

• A stack-up micro electrochemical device was developed based on the carbon paper electrode. • Cobalt-based MOFs and gold nanoparticles improved the metal ion absorption and electron diffusion. • Sensitive simultaneous determination of Pb2+ and Cd2+ achieved the subnanogram LODs. A portable device is conducive to the on-site detection of heavy metal ions at trace level in food and the prevention of related food safety issues. In this work, an electrochemical device stacked up with flat electrodes was developed for the detection of Pb2+ and Cd2+. The top layer of the device is a carbon paper as working electrode, which is modified with amino functionalized cobalt-based metal-organic framework and gold nanoparticles. The bottom layer was constructed with the carbon counter electrode and Ag/AgCl reference electrode, and a punched sample cell (Φ = 8 mm) was in the middle. The proposed method could simultaneously determinate Pb2+ and Cd2+ via anodic stripping voltammetry with the detection limit of 7.0 × 10−2 ng mL−1 and 1.1 × 10−2 ng mL−1, and was applied in real food samples (drinking water, juice, tea, grain, fruits, vegetables, liver and aquatic products) with the recovery of 91.2–105.4 % and 90.2–111.2 %, respectively. [ABSTRACT FROM AUTHOR]

Heavy metal pollution has become increasingly prominent, and bioremediation of heavy metal polluted areas is urgently needed. Broussonetia papyrifera is a pioneer tree species for vegetation restoration in the tailings area, while its molecular mechanism of heavy metal adaptation is not clear. Here, we report that a R2R3 MYB from B. papyrifera (BpMYB1) is involved in Cd accumulation by controlling the down-stream genes and mineral accumulation. Overexpression of BpMYB1 in B. papyrifera resulted in a significant increase in Cd accumulation and multiple gene transcription. Among the up-regulated genes, BpMYB1 could bind to ferrochelatase (BpFC2), basic helix-loop-helix transcription factor bHLH93 (BpbHLH93), and basic leucine zipper transcription factor bZIPs (BpbZIP1 , BpbZIP-CPC1) by recognizing TATCCAOSAMY (TATCCA) motif and related promoter segments. Further investigations revealed that overexpression of BpbZIP1 promotes the absorption of Cd, BpMYB1 regulate Cd uptake in plant relating to Fe accumulation without Fe-deficiency pathway via recognizing the downstream BpbHLH93 and involving in PCs biosynthetic pathway via recognizing the target BpFC2. Moreover, the Cd response effect mediated by BpMYB1 was boosted by interacting with a DELLA protein BpGAI1, a vital member of GA signaling. These results provide new insights into the molecular feedback mechanisms underlying BpMYB1-BpGAI1 controlled Cd uptake in plants, which will benefit for phytoremediation of Cd polluted soil. [Display omitted] • BpMYB1 overexpression benefits for Cd enrichment and tolerance of B. papyrifera. • BpMYB1 could regulate the transcription of multiple genes in Cd stress response. • The Cd stress response of BpMYB1 involves in the gibberellin-dependant signaling. • BpMYB1 could recognize downstream genes of BpFC2 , BpbHLH93 , BpbZIP1 , BpbZIP-CPC1. • BpFC2 , BpbHLH93 , BpbZIP1 , BpbZIP-CPC1 overexpression improves plant Cd uptake. [ABSTRACT FROM AUTHOR]

Herein we report a time and cost – effective approach for rapid determination of Cadmium (Cd) in rice based on electrochemical detection in paper-based analytical devices (PADs). Specifically, double sided conductive carbon tape coated with a thin layer of gold was used as the disposable electrochemical sensors for stripping analysis of Cd (II) coupled with in situ electrodeposition of bismuth. With the gold sputtering time of just 10 s the maximum electrochemical responses of Cd (II) could be obtained, suggesting that retained nanostructure of the carbon tape might facilitate the stripping analysis based on differential pulsed voltammetry. Under optimized experimental parameters, the concentration of Cd (II) from 2 to 150 μg L −1 could be linearly detected with the detection limit of 0.1 μg L −1 . Because of the requirement of low sample volumes in PADs, more importantly, our approach could quantify Cd in rice samples with the weight of about two hundreds of milligrams, which could be treated using a muffle burner with the duration of around one hour. This study implied the practical potential of paper-based analytical devices in the field of rapid detection. [ABSTRACT FROM AUTHOR]

Paper mill sludge (characterized by 29.0% of organic substances such as cellulose, lignin and tannins and 71.0% of inorganic substances such as kaolinite and carbonates) was studied in a mixture with soil in order to evaluate its effects on soil capability for retaining heavy metals. Attention was focused on cadmium and lead sorption and two parameters were investigated, the contact time of paper mill sludge–soil mixture and the paper mill sludge–soil ratio in the mixture. Results showed that paper mill sludge and soil interact to form ‘new’ sorbing sites. Taking into account sorption results of lead, the retention of which by soil is substantially increased by sludge addition, can highlight this modification. Also, the amount of sorbed cadmium was increased by sludge addition. [Copyright &y& Elsevier]

Chromatographic columns packed with paper mill sludge are employed for metal ion recovery from water. The breakthrough curves show that cadmium, copper, lead and silver are removed from acid solutions (pH 2, 4); the affinity series is Pb(II)>Cu(II)>Ag(I)>Cd(II). Both the amount of metal retained and the metal–matrix interaction are pH dependent; the sorptive capacity increases with increasing pH. When the metals are present together at the same initial concentrations a competition among the different ions occurs although the affinity order remains unchanged. In metal recovery from the paper mill sludge column, the total amount of the cadmium and copper is displaced by HCl 1.0 M, 65% of the lead by HCl 0.1 M and 75% of the silver by HNO3 0.1 M. More than 95% of copper and lead and less than 20% of cadmium were recovered with HCl 0.1 M when the metals were present at the same time. [Copyright &y& Elsevier]

Paper-based sensor is a new alternative technology to develop a portable, low-cost, and rapid analysis system in environmental chemistry. In this study, ion imprinted polymers (IIPs) using cadmium ions as the template were directly grafted on the surface of low-cost print paper based on the reversible addition-fragmentation chain transfer polymerization. It can be applied as a recognition element to selectively capture the target ions in the complex samples. The maximum adsorption capacity of IIPs composites was 155.2 mg g –1 and the imprinted factor was more than 3.0. Then, IIPs-paper platform could be also applied as a detection element for highly selective and sensitive detection of Cd(II) ions without complex sample pretreatment and expensive instrument, due to the selective recognition, formation of dithizone-cadmium complexes and light transmission ability. Under the optimized condition, the linear range was changed from 1 to 100 ng mL –1 and the limit of detection was 0.4 ng mL –1 . The results were in good agreement with the classic ICP-MS method. Furthermore, the proposed method can also be developed for detection of other heavy metals by designing of new IIPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A three-electrode system for cadmium detection with paper-based channels. • Detection areas and channels were created by forming a hydrophobic barrier on a paper using the wax. • Usage of 5 wt/wt% antimony precursor the carbon working electrode increased the sensitivity by 2.18 times. • The usage of a PET film decreased the price of the electrode, thereby rendering it suitable for disposable sensors. This paper describes the development of a heavy metal sensor with point-of-care detection for heavy metal detection based on paper channel. A heavy metal detection sensor using a three-electrode system was fabricated on the surface of PET by screen printing. The working electrode is made of carbon paste containing antimony precursors, the reference electrode is made of Ag/AgCl paste, and the auxiliary electrode is made of carbon paste. The fabricated three electrodes were designed to deliver target substance through a paper-based channel to allow very easy point-of-care detection. When measuring cadmium, the fabricated three electrodes showed the highest sensitivity when the antimony precursor concentration was 5 wt/wt%, which was about 2.18 times higher than that of the carbon paste electrode. The fabricated heavy metal sensor had a cadmium detection range of 20–2000 μg/L and a linear coefficient (R2) of 0.988 in the detection range of 20–500 μg/L. The developed paper channel-based heavy metal sensor can be fabricated at a very low cost and is expected to be applicable to other heavy metal detection applications. [ABSTRACT FROM AUTHOR]

Cadmium ion (Cd (II)) is a highly toxic heavy metal usually found in natural water. Exposure to Cd (II) can produce serious effects in human organs such as Itai-Itai disease. Therefore, the maximum allowance levels of Cd (II) in drinking water and herbal medicines imposed by the World Health Organization (WHO) are 3 μg L−1 and 300 μg kg−1, respectively. In this work, nitrogen-doped graphene quantum dots (N-GQDs) as a fluorescent sensor for Cd (II) determination was developed in both solution-based and paper-based systems. N-GQDs were synthesized from citric acid (CA) and ethylenediamine (EDA) via the hydrothermal method. The synthesized N-GQDs emitted intense blue fluorescence with a quantum yield (QY) of up to 80%. The functional groups on the surface of N-GQDs measured by FTIR were carboxyl (COO−), hydroxyl (OH−), and amine (NH 2) groups, suggesting that they could be bound to Cd (II) for complexation. The fluorescence intensity of N-GQDs was gradually enhanced with the increase of Cd (II) concentration. This phenomenon was proved to result from the fluorescence enhancement (turn-on) based on the chelation enhanced fluorescence (CHEF) mechanism. Under the optimum conditions in the solution-based and paper-based systems, the limits of detection (LODs) were found to be 1.09 and 0.59 μg L−1, respectively. Furthermore, the developed sensors showed relatively high selectivity toward Cd (II) over ten other metal cations and six other anions of different charges. The performance of the sensor in real water and herbal medicine samples exhibited no significant difference as compared to the results of the validation method (ICP-OES). Therefore, the developed sensors can be used as fluorescent sensors for Cd (II) determination with high sensitivity, high selectivity, short incubation time (5 min). As such, the paper-based strategy has excellent promising potential for practical analysis of Cd (II) in water and herbal medicine samples with a trace level of Cd (II) concentrations. [Display omitted] • Novel paper-based N-GQDs sensor for trace-level probing of Cd (II) was developed. • User-friendly probing involved chelation enhanced fluorescence (turn-on) mechanism. • Sensor had high selectivity toward Cd (II) over 16 other metal cations and anions. • Sensor offers simple fabrication, high sensitivity, and short incubation time. • Sensor was validated by ICP-OES and applicable for real water and medicine samples. [ABSTRACT FROM AUTHOR]

The presence of toxic metals on paper pulp and the migration of these metals to food from the food package is receiving significant attention. The final exposure levels for consumers depend on two main processes. First the potential of metals to bind paper pulp during manufacture. Second, the metal potential to migrate from paper to food during storage and use.Binding and unbinding processes are modelled for cadmium kinetics through kinetic approaches.The cadmium concentration in paper pulp is estimated from the cadmium concentration in the water–pulp liquor during manufacture, the temperature, and contact time. Two food simulants have been employed for desorption studies, water and acetic solution (3%, w/w). As expected, under acidic conditions desorption is total and rapid (close to 100% desorption reached in a few minutes). However, the desorption of cadmium into the neutral food simulant depends on the initial cadmium concentration in the paper pulp, temperature and contact time. Surface response curves for each combination are presented.Temperature did not affect cadmium binding, but played a significant role for the desorption processes into the neutral food simulant.The proposed equations offer a good fitting of the experimental values, with p<0.001 and residuals within a factor of 3 for over 99% of the measured data. These models allow estimations of the expected exposure levels in consumers, on the basis of manufacture and use conditions. Linking the expected exposure with toxicity thresholds, such as the admissible daily intake (ADI), would allow a scientific assessment of the maximum acceptable cadmium levels in water–pulp liquors during manufacture and in the final paper pulp on the basic of the use patterns of each food packaging material. [Copyright &y& Elsevier]

[Display omitted] • A simple and easy approach for detecting Cd2+ in drinking water has been developed. • Ten percent of horseradish peroxidase inhibition (IC 10) was achieved with 0.1 ppb of cadmium ions. • The PADs platform allowed the detection of Cd2+ in a simple and eco-friendly approach. With the knowledge of the extent of damage caused by cadmium ions (Cd2+), it becomes imperative to detect the presence of Cd2+ in drinking water with a rapid, efficient, and selective analytical method. Herein, a facile and novel colorimetric method for detecting cadmium ions, based on the irreversible inhibition of horseradish peroxidase (HRP) enzyme was established. Alternatively, a low-cost and affordable paper-based analytical device integrated with a smartphone platform was further designed to visualize, on-site and quantitative detection of Cd2+. The method developed for Cd2+ detection is of great interest to ensure a rapid diagnosis of water quality. Under the optimal conditions, the limit of detection of cadmium ions was 0.1 ppb, which is much lower than the permissible limit of WHO (5 ppb) for human exposure. Interference measurements showed that the method exhibited good selectivity. The proposed method was successfully applied as a rapid screening for cadmium ions monitoring in drinking water. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a new device was applied for direct solid sampling flame atomic absorption spectrometry. It was used for trace determination of cadmium in biological samples (bovine and chicken liver). Test samples (0.5 to 7 mg) were weighed into small paper capsules, which were introduced into a quartz cell heated by an air-acetylene flame. Operational conditions for the proposed system were evaluated. There was no significant difference between the results obtained with the proposed system and those obtained after digestion and determination by conventional graphite furnace atomic absorption spectrometry. Good agreement was also obtained with the certified values of two reference materials. Background signals were always low. The characteristic mass was 0.34 ng and relative standard deviation was less than 8%. The limit of detection for the proposed procedure was 1.6 ng or 0.23 μg g− 1 if a sample mass of 7 mg was used. Excluding the steps for sample preparation (drying, milling and weighing), the proposed system allows the determination of 40 test samples per hour and it can be easily adapted to conventional flame atomic absorption spectrometers. [Copyright &y& Elsevier]

Deals with a study which described the kinetic equation of cadmium mobility. Experimental details; Analysis of cadmium kinetics in various temperatures; Results and discussion.

• An AIE-based colorimetric fluorescent probe for detection of Cd2+ was prepared. • The colorimetric sensor uses EDA-GO as a colorimetric reference. • The probe has highly selective and sensitive to Cd2+ with LOD is 33.3 nM. • Fluorescent paper strips are portable and widely used for on-site detection. • Smartphone analysis platform can realize rapid quantitative detection of Cd2+. Instrument-free, portable and direct read-out mini-devices have wider application prospects in various fields, especially for real-time/on-site detection in environmental science. Herein, a colorimetric fluorescent sensor for detecting cadmium ions (Cd2+) based on aggregation-induced emission (AIE) was established, fluorescent paper strips integrated with smartphone platform was further designed for the visualization, on-site and quantitative detection of Cd2+. The colorimetric fluorescent sensor was prepared by mixing orange emission glutathione-stabilized gold nanoclusters (AuNCs) with blue emission ethylenediamine functionalized graphene oxide (EDA-GO), and introducing copper ions (Cu2+) to quench the orange emission of AuNCs while the blue emission served as a background reference without color change. The Cd2+ can induce Cu2+-GSH-AuNCs to aggregation and emit orange fluorescence, causing the fluorescent color of the sensor changed from blue to red with the limit of detection (LOD) as low as 33.3 nM in solution. Moreover, fluorescent paper strips integrated with smartphone platform has a sensitive detection of Cd2+ with the LOD of 0.1 μM in rice samples. The method reported here might have great application prospects in real-time monitoring of foods safety and environmental protection. [ABSTRACT FROM AUTHOR]

The authors of the title paper (J. Mol Struc. 1204 (2020) 127,457) claim to have grown a so-called 'Cadmium (II) dibromide l - Proline monohydrate' (CBLPM) crystal by the slow evaporation method and studied its crystal structure by Rietveld refinement technique. In this comment, many points of criticism, concerning the crystal growth, Rietveld refinement, spectra and theoretical study of the so called CBLPM crystal are highlighted. • The title paper is critiqued. • Many points of criticisms are highlighted. • No Cd or Br atoms in the CIF file of Rietveld refinement. • Cadmium (II) dibromide l - Proline monohydrate is a dubious crystal. [ABSTRACT FROM AUTHOR]

Microfluidic paper chip combined with ion imprinting technology and ZnSe quantum dots for the detection of cadmium and lead ions in oceans and lakes. • A novel ZnSe quantum dots-based MIP paper microfluidic devices (μPADs) was developed. • ZnSe quantum dots are less toxic to the environment. • The rotary μPADs gave a flexible convenient way to multiplexed detection of Cd2+ and Pb2+. In this study, a newly fluorescent ZnSe quantum dots (QDs) with ion imprinting technology was firstly realized on the three-dimensional (3D) rotary paper–based microfluidic chip platform which can be used to realize specific and multiplexed detection of Cadmium ions (Cd2+) and Lead ions (Pb2+). Compared to CdTe quantum dots, ZnSe quantum dots are less toxic and more environmental friendly. In addition, this design improved the portability of the device by transferred the liquid phase of ZnSe QDs@ion imprinted polymers to solid glass fiber paper. Moreover, the 3D rotary microfluidic chip (μ PADs) showed great advantages including low cost, simple and fast facile operation, multiplexed detection, and showed good sensitivity and selectivity. Under optimal experiment conditions, our proposed method was enabled to realize specific and multi-channel determination of Cd2+ and Pb2+ ions. The developed sensor of Cd2+ μ PADs provided a linear response from 1 to 70 μg/L with a lower detection limit of 0.245 μg/L, and Pb2+ μ PADs provided a linear response from 1 to 60 μg/L with a lower detection limit of 0.335 μg/L, respectively. Excitingly, this newly designed 3D rotary μ PADs exhibited quantitative information conveniently, which showed the promising application prospects to rapid testing target metal ions in environmental in the future. [ABSTRACT FROM AUTHOR]

We successfully absorbed the copper ion (Cu2+) and cadmium ion (Cd2+) from alkaline aqueous solutions using the prepared chitosan-tannin (CTS/TA) functional paper as absorbent materials. The kinetics of the adsorption, the adsorption isotherms, and the influence of the solution flow rate and pH were investigated detailly. The adsorption data were described well by Langmuir isotherms, with maximum copper (Cu2+) and cadmium (Cd2+) adsorption capacities of 684.93 and 813.01 mg/m2, respectively. The experimental results also showed that the adsorption of these heavy metals was selective in the order of Cu2+ > Cd2+, as Cu2+ competed with Cd2+ for bonding sites at solution concentrations greater than or equal to 200 mg/L. The results of this study illustrated that the chitosan-tannin functional paper materials mainly followed a complexation-adsorption model, and the best adsorption capacity was achieved at pH = 9. The desorption of heavy ions from this adsorbent and its reusability of functional paper was also involved. Therefore, this novel, environment-friendly functional paper can surely act as an effective adsorbent for the removal and recovery of heavy metals in alkaline aqueous solutions. • An environment-friendly functional paper was used as an effective adsorption material. • The adsorption of Cu2+ and Cd2+ on functional paper followed a complexation-adsorption model. • This paper-based absorbent showed an excellent desorption capability and reusability. [ABSTRACT FROM AUTHOR]

• A response to the title paper is reported. • CCDC number is corrected. In a recent publication, Srinivasan and Gobre [1] commented on our research findings [2]. In this letter to Editor, I wish to respond to the comments. [ABSTRACT FROM AUTHOR]

• Cadmium phytoxicity: A potential threat to crop system. • Calcium signalling: A response to cadmium-phytotoxicity. • Nitric oxide: Significance in plant cadmium tolerance. • Ca2+ and NO crosstalk and its role in cadmium tolerance. Despite its known phytotoxicity, cadmium (Cd) is being added in most arable soils via different agricultural activities. Additionally, information is meager on the Cd-phytotoxicity mitigation strategies employing sustainable approaches. Essential plant nutrient calcium (Ca2+) and signaling molecule nitric oxide (NO) are known as the key regulators of plant biochemical and physiological processes under stress conditions. Though there exists a close functional synergism between Ca2+ and NO in plant stress tolerance, the role of either Ca2+ and/or NO has been explored in plant stress tolerance in isolated reports. Given this, in addition to briefly overviewing the availability, uptake, transport and toxicity (including impact on morpho-physiological traits, photosynthesis, oxidative stress, and genotoxicity), this paper aimed to highlight the general roles, transport, and signaling of Ca2+ and/or NO in plants, and appraises the literature available on their significance in improvements of plant growth, photosynthesis and control of oxidative stress under Cd stress. Effort was also made to present a crosstalk on Ca2+ and NO signaling, and the significance of its outcome in plant Cd-tolerance. [ABSTRACT FROM AUTHOR]

• The addition of nickel ions to the co-precipitation can produce a new hydrotalcite adsorbent with a better structure (FeMnNi-LTH). • Lead and cadmium can be strongly adsorbed by FeMnNi-LTH during a broad pH range. • The adsorption of Pb and Cd by FeMnNi-LTH can theoretically reach 279.13 mg/g and 76.99 mg/g at 25 °C. • FeMnNi-LTH adsorbs heavy metal ions mainly through precipitation and surface complexation. This paper discusses the application of a layered triple hydroxide (FeMnNi-LTH) in removing Pb2+ and Cd2+ ions from aqueous solutions. The material was synthesized via co-precipitation, adhering to a molar ratio of 1:1:2 (Fe:Mn:Ni). It was characterized using FTIR, XRD, SEM and TEM. The results indicate that the synthesized material is classified as a hydrotalcite and exhibits a well-defined layered structure. Batch experiments were conducted to investigate the adsorption of Pb2+ and Cd2+ by FeMnNi-LTH, taking into account various factors such as coexisting ions, pH, temperature, adsorbent dosage, and contact time. The experimental results showed that the adsorption capacity of this material for Pb2+ and Cd2+ was 253.89 mg/g and 56.90 mg/g at 25 °C, respectively. Moreover, it exhibits a consistent high adsorption capacity across a broad pH range (pH 3–5.5). When cations coexist, they compete for adsorption sites in the following order: Zn2+ > Ca2+ > Mg2+ > Cd2+/Pb2+. Based on the calculated thermodynamic parameters, it is inferred that the adsorption process is endothermic and spontaneous. The adsorption mechanism, as analyzed by modeling and characterization, involves isomorphic substitution, surface complexation, precipitation, electrostatic attraction, and physical adsorption. The quantitative analysis of the adsorption mechanism revealed that FeMnNi-LTH primarily adsorbs Pb2+ and Cd2+ via precipitation and surface complexation. It was revealed by comparison with other adsorbents that the synthesized FeMnNi-LTH can be used for remediation of heavy metal pollution in water. [ABSTRACT FROM AUTHOR]

Heavy metals can adversely affect the growth and metabolic processes of plant. Arbuscular mycorrhizal (AM) fungi, which colonize the roots of most plants, may change the uptake and resistance to heavy metals by altering plant metabolism. But few published papers focused on how AM fungi enhanced plant tolerance to heavy metals at the metabolomics level. Therefore, our study incorporated LC-MS technology to explore the molecular mechanism by which AM fungi improved cadmium (Cd) tolerance of Bahia grass (Paspalum notatum) at the metabolomic scale. The results showed that AM fungi increased growth of Bahia grass, and enhanced its uptake and tolerance of Cd. Infection with AM fungi significantly raised the levels of both primary metabolites (amino acid, carbohydrate, organic acid, etc.) and secondary metabolites (such as terpenoids, phenolic compounds, and alkaloids), which in turn improved the photosynthesis efficiency, osmoregulation, and antioxidation defense of the plant, thereby enhancing the Cd tolerance of Bahia grass. Furthermore, under high concentration of Cd, both TCA cycle and lipid metabolism were generally suppressed, and AM fungi inoculation alleviated the effects and normalized the TCA cycle and lipid metabolism. In all, the metabolic alterations identified here provided insights into the mechanisms by which AM fungi enhanced plant tolerance to heavy metals. [Display omitted] • AM fungi altered the metabolism of Bahia grass and increased the tolerance to Cd. • AM fungi enhanced the buildup of primary metabolites, including amino acids. • Increased secondary metabolites by AM fungi ameliorated the harm of Cd to plant. • AM fungi restored the TCA cycle of plants to normal functioning under Cd stress. • AM fungi promoted lipid metabolism, thereby mitigating potential damages by Cd. [ABSTRACT FROM AUTHOR]

Abstract: This paper identifies several drawbacks in the models of absorption and desorption of cadmium presented by [Garcia-Gomez, C., Carbonell, G., 2004. Modelling the absorption and desorption of cadmium on paper pulp using kinetic approaches. Chemosphere 55, 869–878]. It then provides suggestions on improving the effectiveness of the model. [Copyright &y& Elsevier]

In this paper dislocations and twins formed under Vickers indentation of different planes of CdWO 4 crystals are studied. It has been found that on (010) and (100) faces fresh dislocations run along [001] from an imprint of Vickers pyramid. On (001) twins with (010) twinning plane induced by indenter propagate along [100]. Twins with {011} twin planes are induced by indentation on (100). Possible dislocation dissociation reactions and role of the resulting partial dislocations in twinning during microindentaion in cadmium tungstate are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Garlic Se absorption and transportation were largely affected by Se speciation. • Organic Se was superior to inorganic Se in enriching Se and antagonizing Cd. • Bulb Se content treated with organic Se was about twice (or more) than inorganic Se. • Organic Se was significantly more effective in reducing Cd content than inorganic Se. • Se was mainly enriched in bulb, Cd was enriched in root under organic Se application. Currently, planting selenium-rich crops using inorganic selenium such as selenate and selenite is used to address human selenium deficiency problems. In this paper, besides the above two traditional inorganic selenium speciation, we chose a new organic selenium speciation of potassium selenocyanoacetate to investigate the different effects of selenium speciation on selenium absorption, selenium transformation and cadmium antagonism via foliar application. Planting experiments showed that the selenium content of garlic bulbs treated with organic selenium was 1.8–3.9 times higher than that of inorganic selenium. Additionally, the absorption and transformation efficiency of organic selenium in garlic was also the highest, reaching over 95 %. Importantly, it was noteworthy that the cadmium content in bulbs treated with organic selenium was significantly lower than the Chinese food safety standard (0.2 mg/kg). Hence, this study provides an efficient organic selenium speciation which is beneficial to meet human selenium requirements and ensure safe utilization of cadmium-contaminated soils. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a common heavy metal pollutant in the environment, and the widespread use of products containing Cd compounds in industry has led to excessive levels in the environment, which enter the animal body through the food chain, thus seriously affecting the reproductive development of animals. Related studies have reported that Cd severely affects spermatogonia development and spermatogenesis in animals. In contrast, the reproductive toxicity of Cd in males and its mechanism of action have not been clarified. Therefore, this paper reviewed the toxic effects of Cd on germ cells, spermatogonia somatic cells and hypothalamic-pituitary-gonadal axis (HPG axis) of male animals and its toxic action mechanisms of oxidative stress, apoptosis and autophagy from the perspectives of cytology, genetics and neuroendocrinology. The effects of Cd stress on epigenetic modification of reproductive development in male animals were also analyzed. We hope to provide a reference for the in-depth study of the toxicity of Cd on male animal reproduction. [ABSTRACT FROM AUTHOR]

A qualitative identification method of heavy metal cadmium concentration in peanut oil with microwave detection technology was presented. Initially, on the basis of national standards, the configured samples were classified into three categories: negative, which did not exceed the national standard; weak positive, which slightly exceeded the national standard; and strong positive, which far exceeded the national standard. Then, the obtained transmission index was subjected to data dimensionality reduction, using three feature dimensionality reduction methods, namely Principal component analysis (PCA) strategy, recursive feature elimination (RFE) algorithm, and RFE-PCA algorithm, respectively, and the dimensionality-reduced data were used as inputs to establish the random forest (RF) classification model, and the results showed that the three feature dimensionality reduction methods could achieve better prediction results. Among them, the RFE-PCA-RF model has the best prediction performance, at this time, the RFE algorithm retains 35 feature points and number of principal components (PCs) is 7. Next, the structure of RFE model is optimized, and the SVM-RFE-PCA-RF model is constructed by using support vector machines (SVM) as its weight allocator and the analysis of the results of its running 50 times reveals that the discriminative accuracy of the prediction set reaches 100% for 31 times, which meets the requirement of high-precision qualitative identification of three types of samples. Therefore, using microwave equipment for qualitative identification of cadmium content in peanut oil is feasible, and the SVM-RFE-PCA dimensionality reduction strategy proposed in this paper is also worth considering in the future. [Display omitted] • Detection of heavy metal cadmium transmission index in peanut oil by microwave detector. • A feature dimension reduction method based on SVM-RFE model is proposed. • Feature extraction algorithm is used to optimize the classification model. • This study used microwave detection to realize qualitatively analysis of cadmium in peanut oil. [ABSTRACT FROM AUTHOR]

• Juveniles of sea bream Sparus aurata were exposed to cadmium chloride for up to 120 days. • The effects of the exposure were evaluated on the hepatopancreas architecture. • In a time-dependent manner, cadmium was absorbed and stored within the tissue. • Severe morphological and functional damages were detected. • Cadmium induced endocrine disrupting effect on parenchyma. In recent decades, cadmium has emerged as an environmental stressor in aquatic ecosystems due to its persistence and toxicity. It can enter water bodies from various natural and anthropogenic sources and, once introduced into aquatic systems, can accumulate in sediments and biota, leading to bioaccumulation and biomagnification in the food chain. For this reason, the effects of cadmium on aquatic life remain an area of ongoing research and concern. In this paper, a multidisciplinary approach was used to assess the effects of long-term exposure to an environmental concentration on the hepatopancreas of farmed juveniles of sea bream, Sparus aurata. After determining metal uptake, metallothionein production was assessed to gain insight into the organism's defence response. The effects were also assessed by histological and ultrastructural analyses. The results indicate that cadmium accumulates in the hepatopancreas at significant concentrations, inducing structural and functional damage. Despite the parallel increase in metallothioneins, fibrosis, alterations in carbohydrate distribution and endocrine disruption were also observed. These effects would decrease animal fitness although it did not translate into high mortality or reduced growth. This could depend on the fact that the animals were farmed, protected from the pressure deriving from having to search for food or escape from predators. Not to be underestimated is the return to humans, as this species is edible. Understanding the behaviour of cadmium in aquatic systems, its effects at different trophic levels and the potential risks to human health from the consumption of contaminated seafood would therefore be essential for informed environmental management and policy decisions. [ABSTRACT FROM AUTHOR]

• We study the effects of an episode of extensive news coverage of cadmium contamination of rice in China in 2013. • The cadmium rice event reduced the incidence of joint or muscle pain (JMP) by 2% in Hunan Province. • Hunan residents switched away from unsafe drinking water sources such as surface water to deep groundwater, which contributed to the reduction in JMP incidence. • Hunan residents also reduced their consumption of rice in response to the event. • Strong evidence is in support of news and public information as supplemental approaches to formal environmental regulation. The paper studies the effects of news media coverage of the 2013 cadmium rice event in China on consumer health outcomes and avoidance behavior. A difference-in-differences analysis shows that the event caused a 2% decrease in the incidence of joint or muscle pain (JMP), a major health outcome of cadmium pollution, in high-cadmium-pollution regions relative to other regions. Individuals with higher income or with more access to traditional TV media or digital media experienced a greater level of JMP reduction. To defend against cadmium pollution, residents in cadmium-polluted regions switched their drinking water from unsafe sources such as surface water to the safe source of deep groundwater and significantly reduced their consumption of rice. Our findings demonstrate the importance of information provision as an informal approach to complement formal environmental regulation and the critical role of news media in environmental regulation and public health. [ABSTRACT FROM AUTHOR]

The studied materials, Cadmium (Cd2+) and Chromium (Cr3+) are highly toxic, and it focuses on investigating various environmental sources, such as industrial processes and waste water. When quantities of Cr3+ and Cd2+ exceed the allowable limit, biological toxicity and hazardous environmental pollution are unavoidable. In order to address this problem, we introduce 5-(5-(4-([2,2':6′,2″-terpyridin]-4′-yl) phenyl) thiophen-2-yl)-7,8,13,14-tetrahydrodibenzo [ a,i ] phenanthridine (TPTP), a dual-emission response chemosensor that employs a colorimetric and fluorescence turn-on approach for the rapid, sensitive, and discriminate detection of Cr3+ and Cd2+ ions. We created a newly designed luminous TPTP sensor based on intramolecular charge transfer (ICT). TPTP sensor probe specifically determined Cr3+ and Cd2+ ions with an immediate colour shift from cyan to green and orange in CH 3 CN: H 2 O (6:4) solvent solution. The permissible level set by the Environmental Protection Agency (EPA) of the United States for the presence of Cr3+ and Cd2+ ions in drinking water was higher than the detection level of 3.5 and 9.7 nM, by this sensor respectively. NMR titrations, HRMS, and theoretical calculation methods were employed to examine the accurate sensing processes of TPTP and complexes. This is an effective method of detecting Cr3+ and Cd2+ ions in an environmental system using a ratiometric methodology. In addition, TPTP was used to determine the concentration of Cr3+ and Cd2+ ions in natural water and food samples. Fluorescent bio-imaging studies revealed that the present sensor TPTP could identify Cr3+ and Cd2+ ions inside living HeLa cells. A paper kit analysis has been done on TPTP , which has a time-to-result of less than 1 s and offers a cost-effective assay. As a result, the platform offers portability. [Display omitted] • A ratiometric probe for Cd2+ and Cr3+ ions based on a thiophene-extended conjugate terpyridine with phenanthridine functionality has been developed. • The sensor TPTP has a good selectivity for detecting Cd2+ and Cr3+ ions and a low detection limit. • The sensing mechanism was confirmed by a 1H NMR titration experiment and a DFT calculation. • The probe worked well for fluorescent bio-imaging of the Cd2+ and Cr3+ ions in both living cells and real resources. [ABSTRACT FROM AUTHOR]

Highlights • The proposed methodology is independent of battery chemistries. • The methodology is developed for Solar Home Systems (SHS) application in rural areas. • The dynamic capacity fading model is highly practical and accurate. • Comparison with empirical model for LiFePO4 battery shows a very close match. • Methodology can be very useful for SHS designers for battery sizing. Abstract The rapid increase in the adoption of Solar Home Systems (SHS) in recent times hopes to ameliorate the global problem of energy poverty. The battery is a vital but usually the most expensive part of an SHS; owing to the least lifetime among other SHS components, it is also the first to fail. Estimating battery lifetime is a critical task for SHS design. However, it is also a complex task due to the reliance on experimental data or modelling cell level electrochemical phenomena for specific battery technologies and application use-case. Another challenge is that the existing electrochemical models are not application-specific to Solar Home Systems. This paper presents a practical, non-empirical battery lifetime estimation methodology specific to the application and the available candidate battery choices. An application-specific SHS simulation is carried out, and the battery activity is analyzed. A practical dynamic battery lifetime estimation method is introduced, which captures the fading capacity of the battery dynamically through every micro-cycle. This method was compared with an overall non-empirical battery lifetime estimation method, and the dynamic lifetime estimation method was found to be more conservative but practical. Cyclic ageing of the battery was thus quantified and the relative lifetimes of 4 battery technologies are compared, viz. Lead-acid gel, Flooded lead-acid, Nickel-Cadmium (NiCd), and Lithium Iron Phosphate (LiFePO 4) battery. For the same SHS use-case, State-of-Health (SOH) estimations from an empirical model for LiFePO 4 is compared with those obtained from the described methodology, and the results are found to be within 2.8%. The relevance of this work in an SHS application is demonstrated through a delicate balance between battery sizing and lifetime. Based on the intended application and battery manufacturer’s data, the practical methodology described in this paper can potentially help SHS designers in estimating battery lifetimes and therefore making optimal SHS design choices. [ABSTRACT FROM AUTHOR]

Water pollution, as the remarkable environmental remediation issue, is a today worldwide concern. Cadmium ion (Cd2+) as a hazardous water pollutant is seriously detrimental to human health, food safety, and ecological areas. Hence, we successfully designed a simple detection array for monitoring of ultra-low levels of Cd2+ ion by combining the advantages of aptamer as a high sensitive and selective sensing probe and zeolitic imidazolate framework-8 (ZIF-8) as a superior fluorescence quenching inducer. To have a portable and on-site detection assay, the aptamer biosensing array (aptasensor) was designed by using a paper-supported substrate. The basis of the designed paper-supported aptasensor was the specific complexation of Cd2+ with the aptamer strand, adsorption of fluorescein-labeled complementary (FAM-CP) strand on the ZIF-8 surface, and fluorescence quenching of FAM molecule after the leakage of the injected target solution on the sample zone of the paper substrate to the detection part. A linear relationship was obtained between the Mean Gray Value index, as a criterion for the fluorescence quenching, and the Cd2+ concentration in the range of 0.1–120 pM with a detection limit of 0.076 pM. The aptasensor could detect Cd2+ in the diverse real sample, including tap water, milk, coffee, and human blood serum. [Display omitted] • A simple fluorescent aptasensor was developed for monitoring of Cd2+ ion. • ZIF-8 as a fluorescence nanoquencher skeleton was utilized for the detection of Cd2+. • Cd2+ was sensitively determined as low as 0.076 pM. • Cd2+ was successfully detected in tap water, milk, coffee, rice, potato, and human blood serum. [ABSTRACT FROM AUTHOR]

In this paper a photoelectrochemical (PEC) aptasensor based on specific recognition with conformational changed after the target Cd(II) identification was fabricated. A ZnO and reduced graphene oxide (ZnO-rGO) nanocomposite with enhanced PEC activity was designed as photoactive material. After the further incorporation of gold nanoparticles (AuNPs) with ZnO-rGO nanocomposite, the enhanced photocurrent signal could be detected owing to the localized surface plasmon resonance and good conductivity of AuNPs. In addition, AuNPs were used as anchors for immobilization of –SH modified aptamer S1. After that aptamer S2 was paired with S1 sequence to form complementary double stranded DNA (dsDNA) on the electrode surface. Methylene blue (MB) was acted as sensitizer and assembled in dsDNA structure to amplify photocurrent response. When Cd(II) was bound to the aptamer presented on the sensing interface, S2 specifically recognized and captured Cd(II), which resulted in the unwinding of dsDNA structure and the separation of MB molecules from the electrode surface with photocurrent response decreased. The photocurrent was detected by a double-working-electrode system, which used the modified electrode as the first working electrode and glassy carbon electrode (GCE) as the second working electrode. Dopamine (DA) was added to the electrolyte and acted as the electron donor, which could be oxidized on the modified electrode and reduced on the GCE to form a cyclic reaction, leading to the enhanced photocurrent response with improved photocurrent stability. This MB sensitized PEC aptasensor exhibited a high sensitivity with a detection limit of 1.8 × 10−12 mol/L (3σ). Thus, a highly sensitive aptasensor with double-working-electrode detection method for Cd(II) determination were established and further applied to the water samples analysis. A novel photoelectrochemical aptasensor for Cd(II) detection is constructed. The double-working-electrode detection system and various methods of signal amplification such as photosensitizer (methylene blue) and electron donor (dopamine) are used to enhance the detection signal with sensitivity improved. Meanwhile, the aptasensor can also be applied to the determination of practical sample with satisfactory result. Image 1 • Methylene blue (MB) was used as DNA intercalator to enhance the photocurrent response and amplify the detection signal. • A double-working-electrode (four-electrode) system is adopted to improve the sensitivity of the aptasensor. • The design of the sensing strategy is novel and can effectively amplify the detection signal. • Practical applications were discussed. [ABSTRACT FROM AUTHOR]

In this paper, the growth of S. bicolor in Cd-polluted sandy clay loam soil in north China, Cd accumulation in plant and the corresponding soil microbial community were characterized when the plant matured (140 d of growth). Cadmium promoted the growth of mature S. bicolor with higher height and heavier dry mass, especially at the spiked level of 1 mg kg−1 soil (P < 0.05). The higher microbial diversity was found under Cd stress at the spiked level of 15 mg kg−1, which basically corresponded with its influence on the plant growth. High-throughput sequencing data demonstrated that the predominant bacterial phyla include Proteobacteria (35.99% for Cd-polluted soil and 35.22% for the control soil), Chloroflexi (21.33% and 20.58%), Actinobacteria (12.00% and 12.89%), Acidobacteria (7.47% and 11.14%), Bacteroidetes (7.37% and 6.96%), Gemmatimonadetes (5.60% and 6.65%), Firmicutes (2.82% and 1.86%), Planctomycetes (2.47% and 0.95%), Saccharibacteria (1.26% and 1.11%). The predominant fungal phyla was Ascomycota , with the relative abundance of 89.96% for the control soil and 86.2% for the Cd-polluted soil. S. bicolor could grow well in sandy clay loam soil in northern China at low Cd lvel, but it could not accumulate cadmium at higher cadmium level. S. bicolor could be used for phytoextraction of cadmium from the lightly Cd-polluted soil. • Cd in low level could promote the growth of S. bicolor in Cd-polluted soil. • The extractable Cd content increased linearly with the added Cd in soil. • High-throughput sequencing was used to analyze the predominant microbial phyla. • The predominant fungal phyla was Ascomycota. [ABSTRACT FROM AUTHOR]

In order to enhance the removal of cadmium from phosphoric acid, it is imperative to explore novel resources that may be utilized for the development of highly effective and environmentally sustainable adsorbents. Cellulose beads are composed of naturally occurring polysaccharide fibers and find extensive utilization across several industrial sectors and applications. Within this framework, this research paper presents a green and simple method for producing porous cellulose beads using date palm fibers as the preferred raw material. The innovation lies in immersing the obtained cellulose beads in a Polyvinyl fluoride (PVDF)/ N , N -dimethylformamide (DMF) suspension as a coating polymer with different concentrations (2.5, 5, 10 %) to maintain their stability in an acidic environment. The surface of cellulose/PVDF beads were subjected to multiple characterizations like Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), size distribution then pH stability confirming that the coating has been perfectly achieved and conserved well the shape of the beads. The coated cellulose/PVDF-2.5 % underwent evaluation by the process of batch adsorption experiments while different parameters were varied including contact time (5, 10, 20, 30, 60, 90 min), temperature (25, 35, 45 and 55 °C), and adsorbent mass (20, 40, 60, 80 and 100 mg). The obtained ICP data showed that the adsorption rate of Cd (II) from phosphoric acid medium decreased while increasing both temperature from 25 to 55 °C and contact time from 5 to 90 min while adding more adsorbent dosage from 20 to 100 mg enhanced the removal percentage. The cellulose/PVDF-2.5 % was more effective with an adsorption capacity equal to 3.4998 mg/g at optimal conditions including 25 °C as the temperature after 5 min as contact time and by adding a mass 100 mg of the biosorbent while the pH = 2 of the solution is maintained the same. The examined material's adsorption processes proved to be exothermic and non-spontaneous, and it proved that the pseudo-second-order model provided the best match for the cellulose/PVDF-2.5 % beads kinetics data. Furthermore, the cellulose beads exhibited exceptional reusability for up to four repeated cycles without undergoing desorption. The present study offers a viable approach for producing environmentally sustainable biomass-derived adsorbents. Additionally, the study validates the potential of cellulose/PVDF beads as an intriguing material for phosphoric acid decadmiation. [ABSTRACT FROM AUTHOR]

• There are no generally agreed criticality concepts and list of critical materials. • The suggested global criticality concept addresses the availability of materials. • Criticality concepts should prioritise long-term sustainability over politics. • All critical materials carry severe long-term sustainability risks to the economy. The demand for raw materials, in particular, for those classified as critical materials, has increased considerably due to the ongoing energy transition and the corresponding surge in the use of renewable energy technologies. In this context, this review paper analyses literature on reserves, resources, and production data of critical materials, which are required for the energy transition, to understand the connection between the present criticality definition and long-term sustainability. The link to long-term sustainability was studied by applying bell curve production projections. The analysis shows that the present criticality concept and classification is predominantly a reflection of a short-term local political construct, which may be consumption- or production-driven, or a mixture of both, depending on the classifying country. Based on material databases and the corresponding logistic production bell curves, severe limitations of primary supply could emerge from materials, such as antimony, cadmium, chromium, cobalt, copper, indium, molybdenum, nickel, silver, and zinc within two decades. Furthermore, all studied materials are projected eventually to be severely critical. Thus, local efforts will likely have a limited capability to effectively address the long-term risk associated with the production and use of critical materials. Moreover, without concerted global effort, the present criticality concept may not be effective in addressing even the short-term supply bottleneck, particularly for the accelerating energy transition, that it aspires to address. Hence, applying the criticality concept at the global level carries special potential to mitigate the supply risk by mobilising all stakeholders based on a well-informed understanding of materials flows. [ABSTRACT FROM AUTHOR]

In solid recovered fuel (SRF) production, type and nature of input waste stream influences the quality of fuel product. This paper presents the influence of input waste stream on SRF production in a mechanical treatment (MT) plant. The SRF was produced at industrial scale from three different types of waste streams: commercial and industrial waste (C&IW), construction and demolition waste (C&DW) and municipal solid waste (MSW). Here, the stream of MSW used for SRF production was energy waste collected from households. In the SRF production from MSW, higher yields of material were recovered in the form of SRF as compared with that of recovered from C&IW and C&DW. Of the input MSW to the MT plant, 72 wt% was recovered as SRF, equivalent to 86% energy recovery. The energy consumed to produce unit tonne of SRF from C&IW, C&DW and MSW was 1153 MJ, 1246 MJ and 1626 MJ, respectively. In the SRF production, removal of chlorine (Cl), lead (Pb) and mercury (Hg) from C&IW feedstock was worse than from C&DW and MSW feedstocks. In the SRF production from C&IW, of the input mass of chlorine, lead and mercury to the MT process 60%, 58% and 45%, respectively was found in the SRF. The SRF produced from C&DW contained the lowest mass fraction of the input chlorine, lead and mercury in comparison with the SRF produced from C&IW and MSW, namely 34%, 8% and 30%, respectively. Among the waste components rubber, plastic (hard) and textile (synthetic) were identified as potential sources of polluting and toxic elements, whereas wood, paper & cardboard and plastic (soft) were found to contain the lowest content of polluting and toxic elements. The pollutant and toxic elements investigated in this research work were chlorine, lead, cadmium, mercury and arsenic. [ABSTRACT FROM AUTHOR]

[Display omitted] • GQDs-AuNCs ratiometric fluorescent sensor was prepared by electrostatic interaction. • The sensor was used to detect Cu2+ and Cd2+ in scallops. • The paper-based sensor can be used for semi-quantitative detection of Cu2+ and Cd2+. • The detection limits are 4.12 nM for Cu2+ and and 943 nM for Cd2+, respectively. Based on the electrostatic interaction, we constructed a ratiometric fluorescence nanomixture of graphene quantum dots-gold nanoclusters (GQDs-AuNCs) for the quantitative detection of Cu2+ and Cd2+. When Cu2+ or Cd2+ was added into the reaction system, the fluorescence of GSH-AuNCs at 565 nm can be quenched by Cu2+ and enhanced by Cd2+ while the intensity of N -GQDs at 403 nm stayed constant. Under the optimized conditions, the fluorescence intensity ratio (I 565 /I 403) of the GQDs-AuNCs system was proportional to the concentration of Cu2+ and Cd2+ in the range of 8×10−8 mol/L-6×10−6 mol/L and 1×10−6 mol/L-4×10−5 mol/L, respectively, with detection limits of 4.12×10−9 mol/L and 9.43×10−7 mol/L, respectively. In the presence of Cu2+ and Cd2+, the paper-based vision sensor would produce visible fluorescent color changes, which can be used for rapid detection on site. The method has been successfully applied to the determination of Cu2+ and Cd2+ in scallops with satisfactory results. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method for rapid and accurate detection of cadmium content in saline soils is proposed. • The method is based on visible-near-infrared spectroscopy and machine learning. • We pre-processed the original reflection spectra using fractional order derivatives. • We constructed three-band spectral index by optimal band combination algorithm, and obtained the corresponding optimal band combinations. • We proposed the MSC-ELM model based on the two-hidden-layer extreme learning machine. Heavy metal pollution in saline-alkali land has a significant impact on the ecological environment and human health. Rapid and accurate inversion of cadmium (Cd) element content in the saline-alkali land is important for environmental protection, saline-alkali soil improvement and conversion of saline-alkali land to cultivated land. Using traditional chemical detection methods to detect the content of heavy metal elements requires a long testing time and has the drawback of high prices. In this paper, we select the saline-alkali land of Zhenlai County as the study area and combine visible-NIR spectroscopy with machine learning models to invert the Cd content in the saline-alkali land. We preprocess the original reflection spectra using fractional order derivatives (FOD), then construct six three-band spectral indices (TBIs) and obtain the corresponding optimal band combination parameters by the optimal band combination (OBC) algorithm. To address the shortcomings of two-hidden-layer extreme learning machine (TELM), this paper introduces new weight parameters among the nodes of the first hidden layer, further extends it to multiple layers on this basis, and proposes the MSC-ELM model. The improved model is compared with several models, such as random forest (RF), partial least squares (PLS) and extreme learning machine (ELM). And the model performance is analyzed and compared by introducing several performance indicators, such as root mean square error (RMSE) and the ratio of the performance to interquartile (RPIQ). The experimental results show that the FOD transformation can eliminate the baseline drift and reduce the spectral noise. The constructed TBIs can effectively enhance the correlation with Cd content relative to the original single band, reduce redundant information and enhance the spectral features. The MSC-ELM model achieves better performance metrics compared to the other models and obtains the optimal prediction performance. This study provides an accurate and rapid method for the detection of Cd content in saline soil, which is important for the improvement and ecological recovery of saline soil. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), a widely concerned heavy metal, is toxic to humans and ecosystems. In this paper, a Cd-polluted town in southeast China was selected to estimate the Cd emissions of human activities into surface water, soil and atmospheric environment. The analysis shows that the total amount of Cd emitted into the environment in 2015 was approximately 43.5 kg, and the majority of those emissions were discharged into the water, accounting for approximately 90.4% of the total Cd emissions. The remaining Cd emissions into the soil and atmosphere accounted for 9.5% and 0.1%, respectively. The industrial production (IP) is the dominant source of anthropogenic Cd emissions, which contributes to 62.1% of the total emissions. The other contributors include aquaculture (AQ), wastewater treatment (WT), living consumption (LC), crop farming (CF) and animal breeding (AB); each accounted for less than 10% of the total emissions. Pigment production is the largest source of IP emissions. According to the results of correlation analysis, the pigment enterprises are responsible for the heavy Cd pollution in local soil. By comparing the spatial position and combing with the local watercourses, the study reveals that the irrigated watercourse is the transmission channels of soil Cd pollution. This study contributes to the analysis of connecting the emission inventory, environmental media and transmission channels of the heavy metal Cd and provides policy supports for the local governments to adopt a life cycle Cd management approach. Unlabelled Image • A Cd emission inventory was established for Dingshu in 2015. • Industrial production is the main source of environmental Cd. • Pigment enterprises should be responsible for soil pollution. • The irrigated watercourses are the transmission channel for soil Cd pollution. [ABSTRACT FROM AUTHOR]

The contaminants, instead of single contaminants, are usually found as chemical mixtures in terrestrial environment. However, little information is now available about the joint effects of heavy metals and farm chemicals on the soil organism. Our current study aimed to assess the combined toxicity of cadmium (Cd) and four pesticides (atrazine, chlorpyrifos, lambda -cyhalothrin and abamectin) to the earthworm (Eisenia fetida) with binary, ternary, quaternary and quinquenary mixtures. Two distinct kinds of bioassay systems were applied in this study, including contact filter paper test and artificial soil test. Synergistic effects were observed from two quaternary mixtures (Cd-Atrazine-Chlorpyrifos- Lambda -cyhalothrin and Cd-Chlorpyrifos- Lambda -cyhalothrin-Abamectin) and one quinquenary mixture (Cd-Atrazine-Chlorpyrifos- Lambda -cyhalothrin-Abamectin) in both bioassay systems. Besides, two binary mixtures (Cd-Atrazine and Cd- Lambda -cyhalothrin) and three ternary mixtures (Cd-Atrazine-Chlorpyrifos, Cd-Atrazine- Lambda -cyhalothrin and Cd-Chlorpyrifos- Lambda -cyhalothrin) also exhibited synergistic effects on E. fetida by the soil toxicity test. It is more practical to evaluate the contaminant toxicities to earthworm by soil toxicity test. Therefore, the effects of chemical mixtures on soil invertebrates might be underestimated by data obtained from single toxicant. Our findings would offer a better understanding of the complex effects of chemical mixtures on non-target living creatures, and these findings provided valuable insights into the interplay of different chemicals in natural environment. • Abamectin showed the highest toxicity to the earthworms by soil toxicity test. • The binary mixture of cadmium-atrazine exhibited synergism by soil toxicity test. • Chemical mixtures containing chlorpyrifos and lambda -cyhalothrin exerted synergy. • Joint toxic effects should be incorporated into the environmental risk evaluation. [ABSTRACT FROM AUTHOR]

• The genotoxicity of Cd to N. benthamiana were investigated by MSAP and 14 candidate genes were isolated. • Four selected genes were intragenic methylated by genome blasting and alignment in database. • Expressions of four selected genes were related to Cd concentration exposed. • The impacts of Cd on alteration of cytosine methylation status in four selected genes were analyzed and confirmed by BSP. • N. benthamiana with silenced four selected genes showed hypersensitive to Cd exposure. In this paper, we evaluated the genotoxicity of cadmium (Cd) in plants by performing a methylation-sensitive amplification polymorphism (MSAP) on the model plant Nicotiana benthamiana. Among 255 loci examined, 14 genes were found to show altered cytosine methylation patterns in response to Cd stress. Four of those genes (NbMORC3 , NbHGSNAT , NbMUT , and NbBG) were selected for further analysis due to their predicted roles in plant development. Cd-induced changes of cytosine methylation status in MSAP fragments of selected genes were confirmed using bisulfite sequencing polymerase chain reaction (BSP). In addition, the expression levels of these genes were found to correlate with cadmium dosage, and a knock-down of these four genes via virus-induced genes silencing (VIGS) led to abnormal development and elevated sensitivity to cadmium stress. Silencing of these four genes resulted in altered cadmium accumulation in different parts of the experimental plants. Our data indicate that cadmium exposure causes dramatic changes in the cytosine methylation status of the plant genome, thus affecting the expression of many genes that are vital for plant growth and are involved in cadmium stress response. [ABSTRACT FROM AUTHOR]

Abstract It is well established that water management can influence the availability of Cd in paddy soil but the role of dissolved organic matter (DOM) characteristics in this process is still unclear. Here, we measured and compared the DOM quantity and quality between flooded and wetted treatments by spectroscopic and chemometric analysis and applied correlation analysis to relate DOM characteristics with availability concentrations of Cd. Ultraviolet–visible showed that aromaticity and hydrophobicity of DOM significantly decreased with time in wetted paddy soil (p < 0.05) but had no significant difference in flooded paddy soil (p > 0.05). According the results from two-dimensional correlation spectroscopy analytical method, humic- and protein-like substances had fast response during cultivation process. Two humic-like substances (C1, C2) and two protein-like substances (C3, C4) were identified from paddy soil-derived DOM by combining emission and excitation matrix spectroscopy with parallel factor. Compared to component C1, C3, and C4, component C2 has stronger aromaticity and hydrophobicity and higher molecular size (665–1000 Da). Its proportion declined markedly during the wetting periods but increased slightly during flooding. Pearson correlation analysis illustrated that flooding was more helpful in immobilizing Cd than wetting due to the aromatic, hydrophobic, and high molecular weight constituents remained in flooded treatments and the substantial decomposition of component C2 in wetted treatments. These results suggested that spectroscopic and chemometric methods are helping to further explain the impacts of DOM quality on Cd availability under different water management practices. Graphical abstract Image 1 Highlights • Spectroscopic and chemometric analysis methods were used in this paper. • Flooding is more conducive to preserve aromatic and hydrophobic substances. • After 60d, available Cd in wet soil is 2.55 mg kg−1 more than that in flooded soil. • Cd availability is strongly related to DOM quality during flooding and wetting. • Wetting mobilizes Cd because aromaticity, hydrophobicity and molecular weight fall. [ABSTRACT FROM AUTHOR]

The paper is aimed at informing on Netzsch STA 409 CD/3/403/5/G apparatus, a specially-adapted type of the commercial STA 409 CD - QMS 403/5 Skimmer Coupling Instrument combining methods of thermal analysis with Knudsen effusion mass spectrometry. Construction parameters as well as advantages and disadvantages of the instrument are presented. The instrument can be used for a broad spectrum of studies in materials field from which some of them, including e.g. thermodynamic and phase transformations studies, study of surface and catalytic processes, investigation of materials on multiscale level, are demonstrated. The new multifunction design as well as the instrument capabilities are discussed with respect to already published information. fx1 • Specially-adapted Netzsch STA Skimmer Coupling Instrument for TA - KEMS is presented. • A few examples of recent thermodynamic and phase transformations studies are given. • Results of TA and vapour pressure measurements of pure Cd and Yb are summarized. • Study of surface and catalytic properties of AgCu alloy nanoparticles is shown. • Advantages and disadvantages of the multifunction instrumental design are discussed. [ABSTRACT FROM AUTHOR]

Abstract There are a number of government directives and regulations as well as many public schemes on the recycling of batteries, in spite of this; the quantity of batteries that are actually recycled is still very low. Current production capacity cannot meet projected demand of Lithium-ion batteries. To counter this, the reclamation and repurposing of metals like cadmium, Lithium and Zinc from used or spent batteries is the only viable scheme. This is both environmentally friendly and economically feasible. An alternative is the selective chemical leaching in the presence of Sulfuric acid and Sodium metabisulfite. In this paper, the effect of these chemicals as well as the solid-to-liquid ratio and time of retention is comprehensively studied. Experiments are designed for the recovery of Zinc and cadmium from the spend Lithium-ion batteries mix. To maximize the recovery of Zinc and cadmium, the combined genetic programming and simulated annealing approach is proposed. Genetic programming is used for the formulation of functional relationship between recovered metals Zinc and cadmium and the inputs (Solid/Liquid ratio, concentration of Sulfuric acid, mass of Sodium metabisulfite and retention time). The optimal input conditions determined using the simulated annealing algorithm includes Solid/Liquid ratio of 11.7%, 0.86 M Sulfuric acid, 0.56 g/g of Sodium metabisulfite and 45 min of retention time. Three dimensions surface analysis reveals that a lower value of Solid/Liquid ratio favours a better yield. The optimal conditions are validated using experiments. This confirms the efficacy of simulated annealing aided genetic programming techniques as well as the optimal conditions of the metal extraction. Highlights • Problem of maximum extraction of Cadmium and Zinc from spent battery mix is undertaken. • Combined genetic programming and simulated annealing approach is proposed. • Genetic programming models fits the cadmium and zinc output very well. • Simulated annealing optimizes the Genetic programming model to obtain the optimum inputs. [ABSTRACT FROM AUTHOR]

Hydrothermal approach was used to synthesize various mass ratio of titanium dioxide (TiO 2)/reduced graphene oxide (rGO) nanocomposites. The adsorption of the heavy metal ions of cadmium(II), lead(II) and copper(II) with nanostructured TiO 2 /rGO nanocomposites was scrutinized and the TiO 2 /rGO (1:1) nanocomposite was chosen as the effective adsorbent. • Various mass ratio of TiO 2 /rGO nanocomposites were synthesized. • The diethyl oxalate acts as capping agent to synthesis of titanium dioxide. • The adsorption of heavy ions with TiO 2 /rGO nanocomposites was scrutinized. • TG3 nanocomposite was chosen as the effective adsorbent. • TG3 exhibit higher electrochemical performance compared to TiO 2 electrode. In this paper, we have studied various mass ratios of titanium dioxide/reduced graphene oxide (TiO 2 /rGO) nanocomposites modified glassy carbon electrode for the electrochemical detection of Cd(II), Pb(II) and Cu(II). The nanocomposite properties were discussed by FESEM, TEM, XRD, FT-IR, BET and UV–Vis results. UV–Vis spectra for absorption edge of TiO 2 /rGO showed a slight red-shift and a further narrowed band gap compared to pure TiO 2. The simultaneous detection of heavy metal ions such as Pb2+ and Cu2+ carried out using cyclic voltammetry and square wave anodic stripping voltammetry methods. This work showed that the TiO 2 /rGO (1:1) has high potential as the effective adsorbent of Cd(II), Pb(II) and Cu(II) ions from aqueous solutions compared to a TiO 2 electrode, because of the TiO 2 /rGO (1:1) inherited both features of the GO and TiO 2. Improved electrochemical performance can be attributed to the presence of graphene oxide to enhance electrochemical properties. [ABSTRACT FROM AUTHOR]

Abstract Cadmium is a toxic heavy metal that has been increasingly regulated over the past few decades. The main exposure routes for the general public are the consumption of certain foods and the inhalation of cigarette smoke. However, additional exposure may occur through the current and historical use of the metal in consumer products. In this paper, the uses of Cd in consumer goods are reviewed, with the focus on brightly-coloured Cd sulphide and sulphoselenide pigments, and measurements of Cd in historical and contemporary products ascertained by XRF are reported. Cadmium is encountered across a wide range of contemporary plastic products, mainly because of the unregulated recycling of electronic waste and polyvinyl chloride. However, concentrations are generally low (<100 μg g−1), conforming with current limits and posing minimal risk to consumers. Of greater concern is high concentrations of pigmented Cd (up to 2% by weight) in old products, and in particular children's toys that remain in circulation. Here, tests conducted suggest that Cd migration in some products exceeds the Toy Safety Directive limit of 17 μg g−1 by an order of magnitude. The principal current use of Cd pigments is in ceramic products where the metal is encapsulated and overglazed. Leaching tests on new and secondhand items of hollowware indicate compliance with respect to the current Cd limit of 300 μg L−1, but that non-compliance could occur for items of earthenware or damaged articles should a proposed limit of 5 μg L−1 be introduced. The greatest consumer risk identified is the use of Cd pigments in the enamels of decorated drinking glasses. Thus, while décor is restricted to the exterior, any enamel within the lip area is subject to ready attack from acidic beverages because the pigments are neither encapsulated nor overglazed. Glass bottles decorated with Cd-based enamel do not appear to represent a direct health hazard but have the propensity to contaminate recycled glass products. It is recommended that decorated glassware is better regulated and that old, brightly-coloured toys are treated cautiously. Graphical abstract Unlabelled Image Highlights • The occurrence and distribution of Cd among consumer products is reviewed. • Cd occurs in small quantities in recycled plastics. • High concentrations of pigmented Cd are encountered in old brightly coloured toys. • The principal contemporary use of Cd is in ceramic products. • However, the main risk of exposure is from Cd enamel used to decorate drinking glasses. [ABSTRACT FROM AUTHOR]

Highlights • The binding behaviors of cadmium to rice proteins were innovatively studied. • The binding of cadmium to rice proteins was thermodynamic favored. • The cadmium in rice proteins can be removed by acids or food metals ions. Abstract In this paper, for the first time the binding behavior of cadmium (Cd2+) to rice proteins (RPs) was studied. The results showed that the equilibrium of binding was reached within 30 min at 303 K with a maximum binding amount (q) of 15.26 mg/g, and the pH was an important factor positively influencing q. At both 308 K and 313 K, the binding of Cd2+ to RPs belonged to spontaneous, endothermic interactions with high-affinity, assigned to a multidentate coordination. Except for acetate, all the investigated competing coordination agents, such as edetate, pyrophosphate and citrate, showed inhibitory effects on RPs-Cd2+ binding, and edetate seemed to be the most effective one. At pH 6.5, calcium, copper and zinc began to restrict RPs-Cd2+ binding when the metal ion concentration reached 500 mg/kg, and the decreasing of pH would strengthen the inhibitory effects of the investigated metal ions including ferric ions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Rapid room-temperature synthesis of Cd-ZIF nanoparticles. • Application of Cd-ZIF as an ultra-high-efficiency adsorbent. • Cd-ZIF reveals 5613.81 mg/g MG ultrasound-assisted adsorption. Abstract In this paper, zeolitic imidazolate framework nanoparticles based on cadmium and 1,1′-carbonyldiimidazole (Cd-ZIF) were prepared. The Cd-ZIF was utilized for ultrasound-assisted removal of malachite green (MG) dye. The Cd-ZIF was characterized through scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectrometry, Brunauer–Emmett–Teller (BET), energy-dispersive X-ray spectroscopy (EDS) and X-ray powder diffraction (XRD). Experimental results revealed that Cd-ZIF could bind the cationic dye using ultra-high adsorption capacity more easily compared with other absorbents. The pseudo second-order and Sips models presented better fit for the uptake of MG as compared with other kinetic and isotherm models. The experimental maximum adsorption capacity of MG onto Cd-ZIF was 3324.17 mg/g at 25 °C. The extremely high performance of Cd-ZIF for adsorption of the MG dye with high adsorption capacity indicated that the Cd-ZIF could be developed to a large scale. The thermodynamic parameters and Ea values confirmed that the adsorption was a spontaneous, chemical and endothermic reaction. The investigation exhibited that the adsorption mechanism may be mainly controlled by both the π-π stacking and electrostatic interaction. Finally, regeneration results illustrated that the adsorbent can be recycled seven times such that its high stability and applicability will continue to be maintained. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Waste expanded polystyrene foam was used to prepare the sulfonated adsorbents. • The prepared adsorbents were used for the first time in the column adsorption for Cd ions. • Thomas model was employed to fit the adsorption breakthrough curve. • The adsorption mechanisms were explained with different influencing factors. Abstract In this paper, the sulfonated hyper-crosslinked polystyrene (SHCP) adsorbents derived from the waste expanded polystyrene foam (WEPS) were prepared by the simple one-step Friedel–Crafts reaction and the subsequent sulfonation. The prepared SHCP adsorbents were used for the first time in the fixed-bed dynamic adsorption experiments for the removal of cadmium (Cd) ions. The maximum adsorption capacity of SHCP for Cd ion reached 0.7 mmol/g at the pH of 7 at the temperature of 25 °C. The influencing factors of the actual industrial wastewater including initial Cd ion concentration, height-to-diameter (H/d) ratio, ionic strength and co-existing ions on Cd ion adsorption breakthrough curve were examined in a fixed-bed column with the SHCP adsorbents. Furthermore, Thomas model was employed to fit the adsorption breakthrough curve and the simulated adsorption capacity ranged from 68.90 to 80.46 mg/g, with the correlation coefficient higher than 0.97. It was found that the decrease of the ionic strength and the Cd ion initial concentration, as well as the increase of the H/d ratio would increase the adsorption capacity and the breakthrough point in the Cd ion column adsorption. In addition, the SHCP showed good Cd ion selectivity over Na ions in the column adsorption. [ABSTRACT FROM AUTHOR]