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In this article, an easy, effective, π-π conjugation non-covalent surface functionalization of multi-walled carbon nanotubes (MWCNTs) was achieved by using ball grinding technology between pristine MWCNTs and esterified styrene-maleic anhydride ester (ESMA) copolymer, resulting in the formation of modified E-MWCNTs dispersion with excellent dispersibility and long storage stability in N-methylpyrrolidone (NMP). The analysis of transmittance spectroscopy, absorption spectroscopy, sedimentation photo, and transmittance electron microscopy (TEM) confirms that the modified E-MWCNT dispersion has a homogeneous dispersion in NMP. Results obtained from thermogravimetry analysis (TGA) and Raman spectroscopy reveal that ESMA copolymer is successfully coated on pristine MWCNTs surface. Compared with the bad dispersibility of MWCNTs in NMP, the physically modified E-MWCNTs-3 dispersion mixed with 0.12wt% ESMA copolymer under the condition of total 6 h ball grinding time using paint shaker can be easily well-dispersed and has good storage stability, and no sedimentation is observed more than 3 months. Furthermore, the method is simple and economical to operate in industry. An easy, effective, π-π conjugation non-covalent surface functionalization of multi-walled carbon nanotubes (MWCNTs) was achieved by using ball grinding technology between pristine MWCNTs and esterified styrene-maleic anhydride ester (ESMA) copolymer, resulting in the formation of modified E-MWCNTs dispersion with excellent dispersibility and long storage stability reported firstly in N-methylpyrrolidone. [ABSTRACT FROM AUTHOR]

Energy saving and emissions reduction in the iron and steel industry is a significant challenge to achieve carbon neutrality and sustainable development. Many studies focus on the optimization of materials, energy and carbon emissions but lack of optimization strategies in the iron and steel industry. A comprehensive and effective system model is still needed to optimize the CO2 emissions to face the production planning of a company in the future. This article applies industrial metabolism to develop a practical optimization model for improving materials consumption and energy consumption in coking, sintering, pelleting, ironmaking and steelmaking, and the minimum carbon emission is set as the optimization objective. The results show that carbon emissions reduce 148.65 kg/ton crude steel compared with the original data with a yield of 8.4 Mt crude steel. In addition, the optimum material and energy consumption of each production unit under different production plans is studied. If breakthrough technologies are not applied to long-route processes, improving scrap steel ratio is the most promising approach for low-carbon manufacturing in the iron and steel industry in the future. [ABSTRACT FROM AUTHOR]

In this work, an easy, green, π-π conjugation non-covalent surface modification of pristine single-walled carbon nanotubes (SWCNT) was carried out by using ultrasonic technology between pristine SWCNT and anionic surfactant (sodium dodecyl benzene cyclate (SDBS) and sodium polynaphthalene sulfonate (SPS)), resulting in the formation of modified SWCNT dispersion with good dispersibility and long storage stability in water. Results obtained from transmittance spectroscopy, absorption spectroscopy, zeta potential analyzer, sedimentation photo, and transmittance electron microscopy (TEM) reveals that the modified SWCNT dispersion has a high degree of dispersion. The analysis of thermogravimetry analysis (TGA) and scanning electron microscope (SEM) confirm that two kinds of dispersants are successfully decorated on pristine SWCNT surface. More importantly, the pristine SWCNT is insoluble, while the modified S2-SWCNT dispersion mixed with 1.25 wt% SDBS and 1.00 wt% SPS correspondingly under the condition of total 3 h ultrasonic time can be easily well-dispersed in water and has good storage stability, and no sedimentation is observed more than 3 months. More importantly, this strategy is green and economical owing to its easy operation in industry. [ABSTRACT FROM AUTHOR]

Background: Low temperature plasma (LTP) exerts a protective effect in inflammation via enhancing MANF expression. Hyperactivation and dysfunction of theca cells induced by inflammatory agents is accompanied by polycystic ovary syndrome (PCOS), which is a common reproductive and endocrine disorder. However, the effect of LTP on theca cells is still unknown. Methods and results: Theca cells were stimulated with IL-1β or TNF-α for 12 h, then treated with LTP for 100 s. After 8 h, medium supernatant and theca cells were collected. Production of androgen from theca cells were detected by ELISA. The PCNA and Annexin V levels in theca cells were detected by using immunofluorescent staining. The levels of PCNA, BCL-2 and BAX were evaluated by western blot and qPCR. MTT assay was used to detect the viability of theca cells. The proportions of apoptosis of theca cells were detected by Flow cytometry. The mRNA levels of androgenic genes were detected by qPCR. The MANF levels in medium supernatant and cell lysate were detected by using ELISA, western and qPCR. BIP and CHOP expressions were detected by using western blot and qPCR. We found that LTP irradiation decreased inflammatory agents-induced upregulation of androgen and androgenic genes in theca cells. And LTP irradiation relieves IL-1β or TNF-α-induced pathological proliferation and apoptosis in theca cells. In terms of mechanism, LTP irradiation increased MANF level in theca cells to inhibit BIP and CHOP expression. Conclusion: These evidences suggest the protective effect of LTP on theca cells in inflammatory microenvironment, and LTP has the potential clinical application of PCOS. [ABSTRACT FROM AUTHOR]

With the development of nuclear energy, large amounts of radionuclides are inevitably released into the natural environment. It is necessary to eliminate radionuclides from wastewater for the protection of environment. Nanomaterials have been considered as the potential candidates for the effective and selective removal of radionuclides from aqueous solutions under complicated conditions because of their high specific surface area, large amounts of binding sites, abundant functional groups, pore-size controllable and easily surface modification. This review mainly summarized the recent studies for the synthesis, fabrication and surface modification of novel nanomaterials and their applications in the efficient elimination and solidification of radionuclides, and discussed the interaction mechanisms from batch experiments, spectroscopy analysis and theoretical calculations. The sorption capacities with other materials, advantages and disadvantages of different nanomaterials are compared, and at last the perspective of the novel nanomaterials is summarized. [ABSTRACT FROM AUTHOR]

Radionuclides with long half-life are toxic, and thereby result in serious threat to human beings and ecological balance. Herein, a simple two-step synthesis method was used to prepare manganese dioxide@polypyrrole (MnO2@PPy) core/shell structures for efficient removal of U(VI) and Eu(III) from aqueous solutions. The adsorption of U(VI) and Eu(III) were investigated under different kinds of experimental conditions. The experimental results suggested that the adsorption of U(VI) and Eu(III) on MnO2@PPy were greatly affected by pH. U(VI) adsorption on MnO2@PPy was independent of ionic strength at pH<6.0, and dependent on ionic strength at pH>6.0. However, Eu(III) adsorption on MnO2@PPy was independent of ionic strength at the whole pH range of experimental conditions. The maximum adsorption capacities (qmax) of U(VI) and Eu(III) were 63.04 and 54.74 mg g−1 at T=298 K, respectively. The BET, XRD, FTIR and XPS analysis evidenced that high adsorption capacities of U (VI) and Eu(III) on MnO2@PPy were mainly due to high surface area and rich metal oxygen-containing group (i.e., Mn-OH and Mn-O), and the interaction was mainly attributed to strong surface complexation and electrostatic interaction. This study highlighted the excellent adsorption performance of U(VI) and Eu(III) on MnO2@PPy and could provide the reference for the elimination of radionuclides in real wastewater management. [ABSTRACT FROM AUTHOR]

Abstract: Lead contamination is a threat for the environment and human health due to lead non-degradability and non-detoxification. Therefore, methods for efficient removal of lead from contaminated waters are needed. Here, a novel material has been synthesised by surface functionalization of magnesium-aluminum layered double hydroxide with citrate (citric-LDH) and applied to the efficient removal of lead from aqueous solutions. Effects of ionic strength and temperature on the adsorption have been evaluated. Results show that lead adsorption by citric-LDH can be used for lead pollution cleanup. Adsorption kinetics were simulated using a revised model. Simulation results show that citric-LDH adsorb lead ions through a more efficient and time-dependent pathway, leading to the rapid and efficient removal of lead ions. [ABSTRACT FROM AUTHOR]

The environmental behavior of radionuclides is mainly dependent on their speciation and microstructures at solid particles. The speciation and microstructures of radionuclides at molecular level can be achieved from advanced spectroscopy techniques and theoretical calculations. In this perspective, we give a brief introduction of the advanced X-ray absorption fine structure (XAFS) technique and theoretical calculation in the analysis of the speciation and microstructures of radionuclides in the natural environment, which is crucial to evaluate the physicochemical behavior of radionuclides in the environment. [ABSTRACT FROM AUTHOR]

Graphene oxide and Ni-Al layered double hydroxides (GO@LDH) nanocomposites were synthesized via a one-pot hydrothermal process, and characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy in detail. The exploration of U(VI) sorption on GO@LDH surface was performed as a function of ionic strength, solution pH, contact time, U(VI) initial concentrations and temperature. Results of Langmuir isotherms showed that the sorption capacity of GO@LDH (160 mg/g) was much higher than those of LDH (69 mg/g) and GO (92 mg/g). The formed surface complexes between surface oxygen-containing functional groups of GO@LDH and U(VI) turned out to be the interaction mechanism of U(VI) with GO@LDH. According to the thermodynamic studies results, the sorption interaction was actually a spontaneous and endothermic chemical process. The sorption isotherms were better fitted with the Langmuir model compared with other models, which suggested the interaction was mainly dominated by monolayer coverage. The GO@LDH nanocomposites provide potential applications as adsorbents in the enrichment of radionuclides from wastewater in nuclear waste management and environmental remediation. [ABSTRACT FROM AUTHOR]

The X-ray absorption fine structure (XAFS) technology has exhibited a very unique application in the study of sorption mechanism, chemical species and microstructures of radionuclides at the natural solid-water interfaces. In this review, the interaction mechanism of radionuclides with clay minerals and nanomaterials under different environmental conditions are summarized from the XAFS spectroscopy analysis. The coordination number and the bond distances of radionuclides, the oxidation-reduction reactions, the influence of humic substances and microorganisms on the species and structures of radionuclides at molecule level are reviewed and compared. This review is helpful to understand the interactions of radionuclides with oxides, natural clay minerals and nanomaterials, which is also crucial to evaluate the physicochemical behaviors of radionuclides in the natural environment. [ABSTRACT FROM AUTHOR]

In this study, chitosan-metal oxide composites (CS-MO) were prepared for graphene oxide (GO) removal from aqueous solutions. The results showed that the GO coagulation on CS-MO was dependent on pH and ionic strength. The maximum GO removal capacities reached 442.5 mg/g on CS-AlO, 425.0 mg/g on CS-ZnO and 421.2 mg/g on CS-MgO, respectively, showing a huge advantage in the efficient elimination of GO from natural water system. The coagulation of GO on CS-MO was dominated by electrostatic attraction in acidic conditions and by hydrogen bonds in neutral and alkaline conditions. The findings are helpful to improve the current understanding of the environmental behavior of GO in natural aqueous systems. [ABSTRACT FROM AUTHOR]

To contribute to the understanding of Eu(III) interaction preperties on hydrous alumina particles in the absence and presence of fulvic acid (FA), the complexation properties of Eu(III) with hydrous alumina, FA and FA-alumina hybrids are studied by batch and time-resolved laser fluorescence spectroscopy (TRLFS) techniques. The continuous increase in the fluorescence lifetime of Eu-alumina and Eu-FA with increasing pH indicates that the complexation is accompanied by decreasing number of hydration water in the first coordination sphere of Eu(III). Eu(III) is adsorbed onto alumina particles as outer-sphere surface complexes of ≡(Al−O)−Eu· (OH)· 7HO and ≡(Al−O)−Eu· 6HO at low pH values, and as inner-sphere surface complexes as ≡(Al−O)−Eu· 4HO at high pH. In FA solution, Eu(III) forms complexes with FA as (COO)Eu(HO) and the hydration water number in the first coordination sphere decreases with pH increasing. The formation of ≡COO−Eu−(O−Al≡)· 4HO is observed on FA-alumina hybrids, suggesting the formation of strong inner-sphere surface complexes in the presence of FA. The surface complexes are also characterized by their emission spectra [the ratio of emission intensities of D → F ( λ=594 nm) and D → F ( λ=619 nm) transitions] and their fluorescence lifetime. The findings is important to understand the contribution of FA in the complexation properties of Eu(III) on FA-alumina hybrids that the clarification of the environmental behavior of humic substances is necessary to understand fully the behavior of Eu(III), or its analogue trivalent lanthanide and actinide ions in natural environment. [ABSTRACT FROM AUTHOR]

In the above referenced publication [1], the Figure 5 and data in Table 1 are correct, but we ignored to present the final pH values of the system, which is very important to understand the properties. [ABSTRACT FROM AUTHOR]

Although graphene oxide (GO) has been used in multidisciplinary areas due to its excellent physicochemical properties, its environmental behavior and fate are still largely unclear. In this study, batch experiments, spectroscopy analysis and theoretical calculations were addressed to promote a more comprehensive understanding toward the coagulation behavior of GO onto TiO2 under various environmental conditions (pH, co-existing ions, temperature, etc.). The results indicated that neutral pH was beneficial to the removal of GO due to the electrostatic interaction. The presence of cations accelerated GO coagulation significantly owing to the influence of electrical double layer compression. On the contrary, the presence of anions improved the stability of GO primarily because of electrostatic repulsion and steric hindrance. Results of XRD, FTIR and XPS analysis indicated that the coagulation of GO on TiO2 was mainly dominated by electrostatic interactions and hydrogen bonds, which were further evidenced by DFT calculations. The high binding energy further indicated the stability of GO + TiO2 system, suggesting that TiO2 can be used as an effective coagulant for the efficient elimination and coagulation of GO from aqueous solutions. These findings might likely lead to a better understanding of the migration and transformation of carbon nanomaterials in the natural environment. [ABSTRACT FROM AUTHOR]