APPLIED CLAY SCIENCE
·
2019
·
IF 3.89
Haiyan Yang,Yang Zhou,Dongshen Tong,Miao Yang,Kai Fang,Chunhui Zhou,Weihua Yu
Cellulose is the most abundant form of biomass on earth, and is considered as an alternative for fuels and chemicals. The hydrolysis of cellulose to platform compounds, such as reducing sugars (RS), is one of the most important ways for the utilization of cellulose. In this study, the solid acid catalysts of SO 4 2− -ZrO 2 /montmorillonite (SZ-Mt) were prepared by coupling SO 4 2− with ZrO 2 and then introducing into the interlayer of Mt using the coprecipitation method. Meanwhile, the catalytic performance of the SZ-Mt catalysts for the hydrolysis of cellulose to RS in water was studied. The catalysts were characterized by XRD , FT-IR, BET, SEM(EDS), NH 3 -TPD and XPS . The catalytic results showed that the SZ-Mt composite calcined at 500 °C with the molar ratio of S/Zr of 0.3 showed the highest total reducing sugars yield of 30.1%. The characterization results revealed that the surface S O bonds of sulfated zirconium oxide could gradually change from O=S-OH groups (type I, -HSO 4 ) to O=S=O groups (type II, -S 2 O 7 ). It was concluded that the surface S-OH groups in type I were responsible for the hydrolysis of cellulose in the low molar ratio of S/Zr and the new S-OH bonds formed by breaking the S-O-S bonds in type II were contributed to the conversion of cellulose in the high molar ratio of S/Zr. Finally, the mechanism of cellulose hydrolysis on the SZ composites was suggested.
研究领域:
化学工程
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2025
·
IF 4.6
Qiming Zhuo,Decheng Chen,Zenan Wang,Wei Han,Yongming Song,Wenli Liu,Peng Xi
The separation of chalcopyrite and molybdenite in porphyry copper–molybdenum ores is challenging owing to their similar floatabilities, making the use of depressants necessary. Inorganic depressants are commonly employed in the flotation industry to increase the difference in hydrophobicity between chalcopyrite and molybdenite; however, these depressants pose significant environmental risks. Recently, novel organic depressants have attracted considerable interest because of their abundance and low toxicity. This study investigated the use of 2,5-dimercapto-1,3,4-thiadiazole (DMTD), an activator recently employed in copper oxide flotation, as a depressant for the separation of chalcopyrite and molybdenite. Micro–flotation experiments demonstrated that DMTD exhibits a notable selective depression effect, significantly suppressing the flotation of chalcopyrite without adversely affecting the flotation of molybdenite. Furthermore, DMTD maintained its depression effect on chalcopyrite flotation even in the presence of xanthate. Contact angle measurements were used to analyze changes in hydrophobicity, corroborating the micro–flotation results, while SEM-EDS elemental distribution maps further confirmed the selective adsorption of DMTD on the chalcopyrite surface. XPS and AFM analyses were conducted to elucidate the microscale interaction mechanism between DMTD and chalcopyrite. The specific interaction sites on the chalcopyrite surface were identified through changes in elemental binding energies, while the evolution of surface morphology revealed how DMTD interacts with chalcopyrite in the xanthate system.
研究领域:
矿物加工
·
冶金学
·
表面化学
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环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
·
2022
·
IF 2.004
Chenyang Xu,Jianliang Zhang,Zhengjian Liu,Anjun Xu,Yaozu Wang,Liming Ma,Chuanhui Li
In order to study the change of each phase and the influence of single oxide during the consolidation of pellets. A systematic thermodynamic calculation was carried out through the phase diagram to study the influence of five oxides (CaO, SiO 2 , Fe 2 O 3 , Al 2 O 3 and MgO) on the phase equilibrium of the hematite pellet system. The results show that the content of CaO has the most significant effect on the content of liquid phase and SPINA. There are critical values for the influence of SiO 2 and CaO on the Ca 3 Fe 2 Si 3 O 12 phase, which are 3.5% and 3.0%, respectively. Through in-situ heating experiments, XRD-Rietveld and SEM-EDS, the macro morphology and phase composition of the hardened samples were compared and analyzed. Finally, a multiple regression model is used to predict the liquid content of hematite pellets, which is effective in predicting the phase component.
研究领域:
冶金工程
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材料科学
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物理化学
·
过程工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
·Vol. 31
·期 16
·23822-23838
·
IF 0
Yu Heng,Zhang Hongliang,Zhang Chenyang,Sun Wei,Han Mingjun,Wang Rong,Wei Xin,Li Songjiang
The rapid development of industrial society is also accompanied by the generation of a large amount of heavy metal wastewater, which has caused serious harm to the ecological environment and human society. Natural sphalerite has an important value in the environmental field due to its own semiconducting properties. In order to effectively remove Ag + from wastewater containing silver, this study develops a natural mineral-based Ag + adsorbent material (sphalerite) based on elemental affinity qualities and mineralization principles. The results of batch experiments showed that the initial Ag + concentration of 50 mg/L reduced to 0.094 mg/L with a reaction duration of 15 min, a sphalerite dose of 5 g/L, an initial particle size of −400 mesh (38 μm), a reaction temperature of 25 °C, and a pH of 5. The highest adsorption capacity is 19.77 mg/g, and the adsorption behavior is consistent with the Freundlich isotherm model and pseudo-second-order adsorption kinetics. The results of solution chemical analysis indicate that the presence of Ag + is primarily influenced by the presence of S 2− . Further analysis using SEM-EDS, FTIR, and XPS techniques reveals that Ag + is chemically adsorb onto the mineral surface, resulting in the formation of Ag 2 S. DFT calculations further confirm the overlap between the Ag 4d orbitals and the S 3p orbitals on the surface of sphalerite, further confirming its chemical adsorption. Mulliken populations suggest that charge transfer occurs between Ag + and S atoms in the sphalerite surface. This research systematically reveals the Ag + adsorption mechanism on sphalerite surface and expands research ideas for treating heavy metal wastewater.
研究领域:
环境科学
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材料科学
·
化学工程
·
物理化学
·
计算化学
✓ 已验证
DOI
Materials Science & Engineering C-Materials for Biological Applications
·
2016
·
IF 3.42
Huan Zhou,Saisai Hou,Mingjie Zhang,Mengmeng Yang,Linhong Deng,Xinbo Xiong,Xinye Ni
In present work condensed phosphates (P 2 O 7 4 − and P 3 O 10 5 − ) were used as phosphate source in induction heating to deposit calcium phosphate coatings. The phase, morphology, and composition of different phosphate-related coatings were characterized and compared using XRD, FTIR, and SEM analyses. Results showed that P 2 O 7 4 − formed calcium pyrophosphate hydrate coatings with interconnected cuboid-like particles. The as-deposited calcium tripolyphosphate hydrate coating with P 3 O 10 5 − was mainly composed of flower-like particles assembled by plate-like crystals. The bioactivity and cytocompatibility of the coatings were also studied. Moreover, the feasibility of using hybrid phosphate sources for preparing and depositing coatings onto magnesium alloy was investigated.
研究领域:
材料科学
·
生物材料
·
表面工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Fang Xu,Yan Yang,Xiaolei Shi,Yulong Liao,Yonggang Liu,Xueying Wang,Fei Xie,Jianbo Hu
Interest in improving the magnetic properties by co-doping has thrived since it is demonstrated that such co-doping can be used to control the microstructure of ferrites at a low sintering temperature . Usually this process involves grain growth and densification by liquid phase sintering or, in some cases, abnormal growth of grain. Here, we study the growth mechanism of the low-sintered LiZnTi ferrites doped with additions of Nb 2 O 5 and Li 2 CO 3 -MgO-ZnO-B 2 O 3 -SiO 2 (LMZBS) glass through characterization of microstructure and magnetic properties. SEM results show that along with the increase of LMZBS glass contents, the change of ferrite grain presents three different stages. At the initial stage, densification of grain is dominant and grain growth is unconspicuous. Due to the increase of LMZBS glass content, the main process at the second stage is grain growth. At the last stage, however, grain growth starts to be suppressed and pores appear again because of competition between the two additives. Corresponding to each stage, the magnetic parameters of the LiZnTi ferrites, including 4π M s , H ci , B s , B r / B s and Δ H , have different trends. Moreover, XRD patterns show that all samples have a pure spinel phase, which means influence of the two additives on crystal structure is negligible. All in all, we obtain a LiZnTi ferrite with uniform and compact microstructure, high saturation flux density ( B s = 294.2 mT), remanence ratio ( B r / B s = 0.87), saturation magnetization (4π M s = 3700.1 G) and low ferromagnetic resonance linewidth (Δ H = 253) at 900 °C.
研究领域:
材料科学
·
磁学
·
陶瓷
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2014
·
IF 2.93
Junxian Wang,Jie Huang,Haolong Xie,Ailan Qu
A photocatalyst composed of graphite-like carbon nitride (g-C 3 N 4 ) and TiO 2 was fabricated by a simple method to calcine the mixture of melamine and TiO 2 precursor. The photocatalyst has enhanced photoactivity for hydrogen evolution from water. Characterization by XRD , FTIR, SEM and elemental analysis showed that the crystal structure and morphologies of composites were affected by the amount of melamine in the composite. The UV–Vis characterization displayed that the optical absorption range of g-C 3 N 4 /TiO 2 hybrid was broadened with a synergistic effect . The photoactivity for H 2 evolution was shown that the best result obtained from the composite with 67 wt% melamine has about 5 times improvement compared with bare TiO 2 or pure g-C 3 N 4 . The enhanced photoactivity might be related with the favorable structure resulted from heat-treatment temperature, and the content of g-C 3 N 4 participating in wide optical absorption, separation and transportation of electronic-holes, as well as morphology of composite.
研究领域:
材料科学
·
光催化
·
氢能
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Peicheng Huang,Weichun Yang,Varney Edwin Johnson,Mengying Si,Feiping Zhao,Qi Liao,Changqing Su,Zhihui Yang
The contamination of soils by mercury (Hg) seriously threatens the local ecological environment and public health. S-functionalized amendments are common remediation technology , yet, Hg re-activation often occurs in the commonly used immobilization remediation by S-functionalized amendments, resulting in an unsatisfactory remediation effect. In this study, a novel FeS–Se functionalized biochar composite (FeS-Se-BC) amendment was prepared and applied for the efficient remediation of Hg-polluted soil. An immobilization efficiency of 99.62% and 99.22% for H 2 O-extractable Hg and TCLP solution-extractable Hg was achieved with the application of FeS-Se-BC (0.05) after 180 d. The analyses of XPS, Hg-TPD, SEM-EDS demonstrated that excellent remediation performance by FeS-Se-BC resulted from the synergistic effect of FeS and Se to form HgS and HgSe concurrently. In comparison to the treatments of biochar and FeS-functionalized biochar (FeS-BC), FeS-Se-BC promoted the transformation of exchangeable, carbonate-bound, and Fe–Mn oxides-bound Hg fractions into organic material-bound, and residual fractions, effectively reducing the risk of Hg-contaminated soil from a highly dangerous level to a low risk. Furthermore, the introduction of Se clearly inhibited the re-activation of Hg and reduced the release of Hg by 81.12% compared to FeS-BC when the ratio of S 2− to Hg was 5: 1 due to the formation of extremely stable HgSe. These results suggest that FeS-Se-BC has good potential for remediation of Hg-polluted soils which provides a new inhibitory idea for Hg re-activation after immobilization.
研究领域:
环境科学
·
土壤修复
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Tan Mao,Xiaoting Shi,Mengchen Liu,Qiang Su,Youliang Cheng,Changqing Fang,Xueke Luo
Ordered mesoporous materials are one of the mesoporous materials with a pore diameter of 2–50 nm. They are a new kind of materials with uniform pore size, highly ordered nanopores and high specific surface area. SBA-15 is a typical ordered mesoporous material. In addition, polymeric composites based on SBA-15 have been widely used in many fields. At present, the characterization of the pore structure of SBA-15 is usually obtained by chemical or physical experiments. However, due to many uncertain factors in the experiment process, it is impossible to know whether the sample meets the experimental conditions before detecting it. The trial and error cost in this process is too high, and repeated measurement experiments will greatly damage the pore structure. In this paper, using computer to simulate the pore size distribution of SBA-15 based on the pore size distribution maps of SEM and TEM images. Firstly, the image is segmented by threshold, then the aperture data are obtained by the maximum inscribed circle algorithm, and finally the probability density curve of aperture distribution is obtained by a statistical method. The results show that the aperture probability density curve obtained by this method is more similar to the real aperture distribution curve. This method provides a reference for reducing the experimental cost in the process of preparing SBA-15.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Yang Zhao,Yi He,Siming Yan,Changhua Li,Hongjie Li,Wen Chen,Jing Yan,Guiyang Wu,Xi Yuan
Owing to the increasingly stringent environmental regulations, eco-friendly waterborne epoxy (WEP) coating currently gets much attention as an alternative choice of traditional coating. But the intrinsic problems of WEP, including poor barrier property and lack of long-term anticorrosion performance, was a limitation for its application. Herein, α-zirconium phosphate (α-ZrP) was prepared and exfoliated under mild condition. Then α-ZrP after exfoliation was functionalized by eco-friendly phytic acid (PA) molecular and a novel nano-filler (PZ) was obtained. The test results of the XRD , FTIR, SEM, TEM and XPS indicated that the preparation of nano-materials was successful. Through the EIS test, the outstanding barrier property of WEP incorporating with PZ was proved. Moreover, the excellent long-term anticorrosion performance of WEP incorporating with PZ was also proved by the salt spray test .
研究领域:
材料科学
·
涂层与薄膜
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Baoping Zhang,Heng Zhang,Yin Wang,Shiyuan Fang
Amine/quaternary ammonium lignin for adsorption of tungsten was synthesized by amination and quaternization from lignin. The adsorbent was characterized by SEM-EDS and FTIR. The effects of pH, initial concentration of tungsten, adsorption time and dosage of adsorbent on the adsorption effect were investigated. The adsorption mechanism was revealed by SEM-EDS and FTIR and XPS. The results showed that amine/quaternary ammonium lignin was loose and rough and contained a large number of phenolic hydroxyl and amine and quaternary ammonium functional groups. Using the optimum conditions, which included the pH of 4.0 and initial tungsten concentration of 800 mg·L −1 and adsorption time of 960 min, the saturated adsorption capacity of 1 g·L −1 amine/quaternary ammonium lignin for tungsten reached 421.68 mg·g −1 . The adsorption followed Langmuir model and quasi-second-order kinetic model, indicating that the adsorption was monolayer homogeneous chemisorption. When the total concentration of tungsten was 0.005 mol·L −1 and the value of pH was smaller than 4.7, H 2 W 12 O 40 6− was the existing form of tungsten and was adsorbed by electrostatic attraction of hydrogen bond and coordination with amino and ion exchange with Cl − .
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 29
·e52649
·
IF 3.057
Chen Gao,Junbo Jiang,Juan Wang,Yutong Wang,Yangyang Zhang,Caihua Rao,Yue Cheng,Zhongrong Chen,Runhuai Yang,Gang Zhao
Mineralization of hydroxyapatite mineralized by acidic metal oxides has attracted substantial research interest in the research and development of orthopedic substitutes. In this study, Polycaprolactone (PCL) nanofibers with nano-tantalum oxide (Ta 2 O 5 ) were successfully fabricated through electrospinning. The scaffold simulates the mineralization process of hydroxyapatite in simulated body fluid. However, in the process of mineralization, there is a chemical reaction between hydrophobic scaffolds and acid oxides, which is believed to have a significant impact on the biological effects of the scaffolds. The results of SEM, EDS, XRD, Mapping, FTIR, GPC, 13 CNMR, and 1 HNMR explain the principle of hydroxyapatite mineralization by Ta 2 O 5 and the reason why the composite scaffold is blurred, that is, the carbonyl carbon of PCL attacked by the surface hydroxyl groups of Ta 2 O 5 to catalyze its ring-opening polymerization to synthesize PCL/Ta 2 O 5 nanocomposites in one step. In order to accurately explore the effect of this reaction on the metabolism of biological macromolecules in the future, we provide a detailed route of Ag Nanoparticles -Dimercaptosuccinic acid@Transcription activator (AgNPs-DMSA@TAT) probe synthesis. The results provide a reference for the sedimentation of hydroxyapatite induced by acid oxides and its effect on traditional electrospun fiber scaffolds.
研究领域:
材料科学
·
生物材料
·
骨科
·
生物医学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）