METALS AND MATERIALS INTERNATIONAL
·
2021
·Vol. 27
·期 12
·5389-5398
·
IF 3.642
Hong S. F.,Lu Z. C.,Liu Y. H.,He Q. M.,Jiang W.,Zeng M. Q.
Abstract Supersaturated solid–solutions in a W–Cr alloy system were fabricated by conventional milling and plasma milling. The different extension mechanisms of the solid solubility that were created by ball milling with and without discharge plasma were studied. The solid–solubility of Cr in W for the P-milling W–Cr alloy system was higher, which indicates that plasma milling promotes the formation of W(Cr) solid–solution more easily than conventional milling. According to Miedema’s model, in the W–Cr alloy system, the free-energy change to form a W(Cr) solid solution by plasma milling is reduced compared with conventional milling because of the heating effect of the discharge plasma. Therefore, a higher stored energy in the grain boundaries and dislocations of the W–Cr nanograins during plasma milling makes it easier to overcome the thermodynamic barrier in the formation of a solid–solution, when compared with conventional milling. Graphic Abstract
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2020
·Vol. 10
·期 8
·942
·
IF 3.52
Zhiying Yan,Zijuan He,Mi Li,Lin Zhang,Yao Luo,Jiao He,Yongjuan Chen,Jiaqiang Wang
In order to further improve the photocatalytic performance of the SiO2/TiO2composite under visible light irradiation, curcumin-doped SiO2/TiO2nanocomposites were synthesized via directly incorporating it into the structure of SiO2/TiO2during the synthesis using an inexpensive and readily available natural pigment (curcumin) as doping agent. The physicochemical properties of SiO2/TiO2nanocomposites were characterized in detail by X-ray diffraction, transmission electron microscopy, Fourier transform-infrared spectroscopy, N2adsorption–desorption isotherms, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. The results indicate that all SiO2/TiO2nanocomposites exhibited an anatase phase with a typical mesoporous structure. It was found that the dope of curcumin in the SiO2/TiO2composite could decrease the crystal size, slightly improve the specific surface areas, significantly enhance the visible light absorption, and effectively narrow the band gap energy from 3.04 to 10(eV). Compared with bare SiO2/TiO2, the curcumin-doped SiO2/TiO2resulted in enhanced photocatalytic reduction activity for Cr(VI) under visible light irradiation, and the CTS (12) sample with the appropriate content of curcumin of 12 wt % shows the photocatalytic yield reaching 100% within 2.5 hours, which is larger than CT (12) without silica. This could be attributed to the curcumin doping and the synergetic effects of SiO2and TiO2in SiO2/TiO2nanocomposites.Keywords:curcumin pigment;SiO2/TiO2nanocomposites;visible photocatalyst;reduction of Cr (VI)
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Yueying Wang,Xuetao Hu,Wenting Li,Xiaowei Huang,Zhihua Li,Wen Zhang,Xinai Zhang,Xiaobo Zou,Jiyong Shi
A novel fluorescent probe based on the static quenching and the inner filter effect between boron nitrogen co-doped carbon quantum dots (B, N-CDs) and Cr(VI) was developed for the quantitative determination of Cr(VI) in real water samples. B, N-CDs were prepared using the hydrothermal method with ammonium citrate and bis(pinacolato) diboron as raw materials. Compared with undoped CDs, the fluorescence properties of the B, N-CDs were improved. The fluorescence quantum yield of the B, N-CDs was as high as 59.01%. After optimization of the experimental parameters, the B, N-CDs could be used as a fluorescence probe to detect Cr(VI). Strong linear correlation ( R 2 = 0.9986) was established in the Cr(VI) concentration range 0.3–500 μM, and a detection limit of 0.24 μM was achieved. Moreover, the B, N-CDs successfully detected Cr(VI) in real water samples, indicating that they have broad application prospects in the sensitive detection of Cr(VI).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hang Yang,Siyu Huang,Yi Zhang,Boxun Zhou,Sanjrani Manzoor Ahmed,Huamin Liu,Yaowen Liu,Yong He,Shibin Xia
In this study, secondary pyrolysis oil-based drilling cuttings ash (OBDCA-sp) was used to remediate chromium (Cr)-contaminated soil. The effects of the OBCDA-sp mesh, OBCDA-sp dosage and soil moisture content on the removal of Cr (VI) were investigated. Subsequently, a kinetic experiment was conducted where the pseudo-first-order and pseudo-second-order kinetic models both fitted well on OBDCA-sp with the adsorption process of Cr (VI) in soil. The change of the chromium form indicated that the addition of OBCDA-sp transformed Cr from an effective state to a stable form, reducing its mobility and bioavailability . X-ray diffraction and Fourier transform infrared spectroscopy analysis were used to verify the potential mechanism of Cr (VI) removal; Ba, Fe, S, and P elements in OBCDA-sp were observed to play a significant role in the reduction of Cr (VI). The results from this study indicate that OBCDA-sp could be an emergent and promising alternative for the remediation of Cr-contaminated soil.
✓ 已验证
DOI
高影响因子
JOM
·
2020
·Vol. 72
·期 3
·1279-1285
·
IF 2.054
Xia Yang,Zhao Jinlong,Dong Zhaowang,Guo Xueyi,Tian Qinghua,Liu Yong
Cobalt-chrome-molybdenum (Co-Cr-Mo) alloy possesses outstanding strength, wear, and corrosion resistance and is a good material candidate for making dental and orthopedic implants. Spherical Co-Cr-Mo powder for additive manufacturing is usually costly due to the high-temperature melting processes and low yield of the powder with desirable particle size in the conventional melt-atomization process. A novel process for making spherical Co-Cr-Mo alloy powder through a simple meltless granulation and sintering process is described herein. The results indicate that the compositional segregation problem can be overcome and high-temperature operation avoided. Segregation-free powder was obtained after sintering above 1200°C. The powder was purified during sintering in a hydrogen atmosphere. The hydrogen purification mechanism is discussed with the aid of thermodynamic modeling using HSC Chemistry software. The oxygen content in the final powder can be controlled to < 0.2 wt.% for powder with particle size < 107 µ m. The final powder retained good spherical morphology.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2021
·
IF 4.464
Peng Wang,Cong Xie,Tong Song,Ping Yang
Amorphous SnO 2 was coupled on the surface of mixed-phase TiO 2 nanoflowers (NFs) by a solvothermal synthesis. Various characteristics confirms the formation of SnO 2 /TiO 2 heterostructures. As-prepared amorphous SnO 2 /TiO 2 heterostructures revealed uniform morphology and enhanced photoelectrochemical performance. Underfull-spectrum light irradiation, the SnO 2 /TiO 2 heterostructures with an optimized SnO 2 ratio revealed the best photoreduction performance, in which Cr(VI) of 99% was removed within 30 min. This is ascribed to the introduction of amorphous SnO 2 , which adjusted the band gap structure, increased specific surface area of TiO 2 NFs, and greatly enhanced the photoelectric conversion efficiency. The mechanism of the heterostructure formation and enhanced photoreduction for Cr(VI) ions were discussed. The TiO 2 NFs with a mixture phase helps to improve the separation efficiency of photogenerated carriers. This result provides an unique idea for the construction of heterostructures.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL QUALITY
·
2021
·Vol. 50
·期 5
·1123-1134
·
IF 2.751
Li Liu,Jinxin Zhao,Weizhao Yin,Sihao Lv,Mei Su,Ping Li,Xiangyu Zheng,Penchi Chiang,Jinhua Wu
In this study, a collaborative system of Fe 0 and mixed anaerobic microorganisms was established for remediating chromium (Cr)-contaminated soil and restraining the translocation of Cr from soil to swamp cabbage ( Ipomoea aquatica Forssk.). Solid phase characterization demonstrated that more reactive secondary minerals such as green rust, magnetite, and lepidocrocite were generated in the composite system as compared with the Fe 0 -only system. Hence, the Fe 0 –microorganisms composite system achieved a remarkably higher aqueous Cr(VI) removal of 85.6%, 2.9 times higher than that in the Fe 0 -only system. After 14 d remediation, easily available Cr(VI) and Cr total species such as water-soluble, exchangeable, and bound-to-carbonates were converted to less available Cr(III) and Cr total species (e.g., Fe–Mn oxides-bound and organic matter-bound species) because of the production of Cr–Fe hydroxides and oxides [Cr x Fe 1−x (OH) 3 or Cr x Fe 1−x OOH] on the Fe 0 surface. A pot experiment showed that Cr uptake by swamp cabbage after the composite system remediation was suppressed by 69.1%, two times higher than that after the Fe 0 -only system remediation. Excessive Fe uptake by swamp cabbage also was efficiently inhibited by the composite system treatment due to enhanced Fe hydroxides and oxides production on the Fe 0 surface because of biological corrosion and mineralization. These results indicated that Fe 0 –microorganisms composite system remediation could efficiently enhance Cr(VI) immobilization and decrease its bioavailability and bioaccumulation by plants, which is a promising technology in Cr-contaminated soil remediation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2021
·
IF 4.158
Ying Wang,Yanhong Liu,Guangbin Li,Mingmin Zheng,Yusha Li,Anlei Zhang,Yingchun Zhang
In this study, Cr coatings were electrodeposited on carbon steel substrates by a trivalent Cr salt. The microstructure of the Cr coatings and their flow accelerated corrosion (FAC) resistance in simulated secondary circuit environments (10 MPa and 150 °C) of nuclear power plants were investigated. The results showed that the as-deposited coating was amorphous and crack-free. Annealing at 200 °C resulted in the decrease of Cr (OH) 3 and the increase of Cr and Cr 2 O 3 on the coating surface , which improved the corrosion resistance of the coating. The subsequent FAC test showed that the Cr coatings significantly improved the FAC resistance of the carbon steel substrate. The coating annealed at 200 °C exhibited better FAC resistance. The Cr-rich oxide film formed on the coatings was mainly Cr 2 O 3 , with a small amount of Cr and CrO 2 . Due to the galvanic effects caused by pinhole defects, abnormally grown annular deposits formed on the coating surface.
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Bo Ma,Jun Yao,Zhihui Chen,Bang Liu,Jonghyok Kim,Chenchen Zhao,Xiaozhe Zhu,Victor G. Mihucz,Tatiana Minkina,Tatjana Šolević Knudsen
In this study, a polydopamine (PDA) modified attapulgite (ATP) supported nano sized zero-valent iron (nZVI) composite (PDA/ATP-nZVI) was rapidly synthesized under acidic conditions, and employed to alleviate Cr(VI) toxicity from an aqueous solution. Kinetic studies revealed that Cr(VI) adsorption process followed the pseudo-second order model, suggesting chemisorption was the dominant adsorption mechanism. Liu isotherm adsorption model was able to better describe the Cr(VI) adsorption isotherm with the maximum adsorption capacity of 134.05 mg/g. The thermodynamic study demonstrated that the adsorption process occurred spontaneously, accompanied by the increase in entropy and endothermic reaction . Low concentrations of coexisting ions had negligible effects on the removal of Cr(VI), while high concentrations of interfering ions were able to facilitate the removal of Cr(VI). Reactive species test revealed that Fe 2+ played a key role in Cr(VI) reduction by PDA/ATP-nZVI. PDA enhanced the elimination of Cr(VI) via donation of electrons to Cr(VI) and acceleration of Fe 3+ transformation to Fe 2+ . Furthermore, PDA was able to effectively inhibit the leaching of iron species and generation of ferric hydroxide sludge . Mechanistic study revealed that 72% of Cr(VI) elimination was attributed to reduction/precipitation, while 28% of Cr(VI) elimination was due to the surface adsorption.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE INDIAN CHEMICAL SOCIETY
·
2021
·
IF 0.284
Jiacheng Li,Xiaoqin Li,Zichuang Wang,Yannan Jia,Kai Xu,Zijie Wang,Zheng Wang
Amino-functionalized magnetic MIL-101(Cr) was prepared via a one-step solvothermal method, characterized, and applied in adsorptive Sb(III) removal. The effects of solution pH, adsorbent dosage, and coexisting substances on the adsorption of Sb(III) by MIL-101(Cr)–NH 2 /MnFe 2 O 4 were studied. The adsorption kinetics were analyzed using pseudo-first order, pseudo-second order, intraparticle diffusion, and Elovich models, while Freundlich and Langmuir isotherm models were used to fit the experimental data. The pseudo-second-order kinetic model provided the best fit for the kinetic data. The maximum adsorption capacity of MIL-101(Cr)–NH 2 /MnFe 2 O 4 for Sb(III) was 91.07 mg/g, as calculated using the Langmuir adsorption isotherm model. Thermodynamic analysis revealed that the adsorption of antimony onto MIL-101(Cr)–NH 2 /MnFe 2 O 4 is spontaneous and endothermic, while response surface optimization revealed that the optimal conditions for Sb(III) adsorption by MIL-101(Cr)–NH 2 /MnFe 2 O 4 are an adsorbent loading of 222.55 mg/L, a pH of 4.5, and a temperature of 294.59 K. The predicted adsorption capacity of MIL-101(Cr)–NH 2 /MnFe 2 O 4 for Sb(III) is only a 1.8% deviation from the actual value. Furthermore, MIL-101(Cr)–NH 2 /MnFe 2 O 4 exhibits strong magnetism, allowing it to be separated from wastewater using a magnet. Finally, a preliminary economic analysis showed that the cost of treating a ton wastewater containing 25 mg/L antimony using this composite would be 26.24 USD. Thus, MIL-101(Cr)–NH 2 /MnFe 2 O 4 is promising for treatment of Sb(III)-containing wastewater.
✓ 已验证
产品关联
DOI
高影响因子
Advances in Materials Science and Engineering
·
2021
·
IF 1.726
Wenjuan Zhang,Yaxian Wang,Yulong Fei,Youliang Wang,Zhaoxiong Zhang,Miao Kou,Qiancheng Feng,Sheng Wang,Xueyan Du
A novel and efficient route is proposed to fabricate Fe3O4/polypyrrole (Fe3O4/PPy) nanotubes via a one-pot process. The one-pot strategy involves the synthesis of Fe3O4/PPy nanotubes by oxidative polymerization of pyrrole (Py) monomer using Fe3+ as an oxidant in the presence of methyl orange (MO) and Fe3+ used as iron source to form Fe3O4 simultaneously in basic conditions without adding any additional iron source and oxidant. The effects of Fe3+ concentration on the morphology and adsorption capacity of the Fe3O4/PPy nanotubes were investigated. The Fe3O4/PPy nanotubes exhibit a tubular structure. Fe3O4 nanoparticles are well dispersed among the PPy nanotubes. The Fe3O4/PPy nanotubes exhibit excellent magnetic property, which make them easy to separate from wastewater by magnetic separation. The diameter of the PPy nanotubes decreased with the increase of the Fe3+ concentration. The Fe3O4/PPy nanotubes showed strong adsorption capability for Cr(VI) with the maximum adsorption capacity of about 451.45 mg·g−1, which is significantly higher than bare Fe3O4 nanoparticles. Cr(VI) was adsorbed on Fe3O4/PPy nanotubes by ion exchange and chelation, where Cr(VI) was partially reduced to Cr(III) due to the existence of −NH+ on the Fe3O4/PPy nanotubes. Furthermore, the Fe3O4/PPy nanotubes are recyclable, retaining 90% of the initial removal efficiency after 5 adsorption/desorption cycles.
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2019
·
IF 6.044
Tao Hu,Qiang Liu,Qinze Liu,Yang Wu,Congde Qiao,Jinshui Yao
Green composite adsorbent with low cost and high efficiency towards toxic Cr(VI) removal from the polluted water has a broad application prospect. In this work, a mussel-inspired Cr-adsorbent namely poly(catechol tetraethylenepentamine-p-phenylenediamine)@as-prepared cellulose (PAC@AC) is successful fabricated via catechol-amine copolymer adhering onto as-prepared cellulose (AC). The detailed characterizations of product are run with SEM, FT-IR, TGA , XRD, EDS and XPS analysis. Many factors are investigated to affect the adsorption of Cr(VI) by PCA@AC, including ratio of AC to PCA, adsorbent dosage, contact time, initial Cr(VI) concentration, pH, temperature and exterior ions. The maximum adsorption capacity of PCA@AC for Cr (VI) is obtained by 507.61 mg/g at 30°C using Langmuir model, which is very higher than the pure AC. The removal ability of PCA@AC is ascribed to the electrostatic interaction and reduction reaction of Cr(VI) to Cr(III) during the adsorption process. In addition, the adsorption process is spontaneous and endothermic, not require any external energy. The composite adsorbent (PCA@AC) has great potential for Cr(VI)-wastewater purification with an excellent chelating ability.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）