Journal of Central South University
·
2014
·Vol. 21
·期 11
·4115-4120
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IF 0.464
Li Xin-she,Liu Zheng-yan,Lu Bu-shi
Ultrasound was applied for the extraction of pectin from chaenomeles . The content of pectin was evaluated by carbazole colorimetric method. Based on the results of the single factor experiment and the orthogonal tests, the optimum extraction parameters are as follows: the solid-to-liquid ratio is 1:4 g/mL, the ultrasonic power is 320 W, the ultrasonic-assisted extraction temperature is 60 °C, the ultrasonic-assisted extraction time is 50 min, and pH value is 2.0. Compared with acid hydrolyze methods, the extraction time of the present technique decreases from 70 min to 50 min, and the extraction yield increases from 1.39% to 2.61%. The results show that ultrasonic-assisted extraction is time-saving and highly efficient, so it provides a new way to extract pectin from chaenomeles .
研究领域:
食品科学
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植物化学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Jiewei Chen,Gaoxiang Wu,Tianyue Wang,Xiaodan Li,Meicheng Li,Yuanhua Sang,Hong Liu
Semiconductor photocatalysts have been widely used for solar-to-hydrogen conversion; however, efficient photocatalytic hydrogen generation still remains a challenge. To improve the photocatalytic activity, the critical step is the transport of photogenerated carriers from bulk to surface. Here, we report the carrier step-by-step transport (CST) for semiconductor photocatalysts through precise defect engineering. In CST, carriers can fast transport from bulk to shallow traps in the defective subsurface first, and then transfer to the surface active acceptors. The key challenge of initiating CST lies in fine controlling defect distribution in semiconductor photocatalysts to introduce the special band matching between the crystalline bulk and defect-controllable surface, moderate bridgelike shallow traps induced by subsurface defects, and abundant surface active sites induced by surface defects. In our proof-of-concept demonstration, the CST was introduced into typical semiconductor TiO2 assisted by the fluorine-assisted kinetic hydrolysis method, and the designed TiO2 can exhibit the state-of-the-art photocatalytic hydrogen generation rate among anatase TiO2 up to 13.21 mmol h–1 g–1, which is 120 times enhanced compared with crystalline anatase TiO2 under sunlight. The CST initiated by precise defect distribution engineering provides a new sight on greatly improving photocatalytic hydrogen generation performance of semiconductor catalysts.
研究领域:
材料科学
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能源化学
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环境科学
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DOI
PubMed
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2025
·Vol. 42
·期 3
·621-632
·
IF 3.2
Lou Wen-bo,Liu Dong-yan,Wang Yun,Zhao Da,Sun Zi-cheng,Zou Yi,Wang Sheng-yan,Cheng Quan-guo,Li Jian-zhong,Liu Hong-hui
Nowadays, the recycling of spent lithium-ion batteries is a key concern in the energy field. Among them, for the purification of Li-containing mother liquor, the targeted multi-means coupling impurity removal methods are mostly employed, which however, inevitably lead to a Li loss of 3–5% and high costs. In this study, a multi-stage hydrolysis method, combining the residual P and Al, Mg, Cu, Zn, Ni, Fe, forming hydroxide-phosphate co-precipitation for the synergistic impurity separation, was adopted. Thermodynamic calculations show that Li + and Mg 2+ are insensitive to pH when pH < 10, and Al, Cu, Zn, Ni, Fe behave similarly in nature. The impurities should be precipitated as: Fe 3+ > Al 3+ > Cu 2+ > Ni 2+ > Zn 2+ > Mg 2+ , with phosphate precipitating first, followed by converting into hydroxide as pH rising. Actual results showed that the order was P > Fe & Al & Cu & Ni & Zn > Mg, and the process was divided into three steps, with separation points at pH = 2.37, 8.66, and 11.00, respectively. All the impurity removal efficiencies were close to 100%, the loss of Li was 1.74%. The optimal conditions for Li 2 CO 3 precipitation were determined: an Na 2 CO 3 addition of 1.5 times the theoretical amount, a temperature of 90 °C, a reaction time of 4 h, and a one-time addition of dosing method. Li precipitation efficiency reaches 90.10%, with a 99.95% purity. The results effectively reduced Li losses and provided a practically feasible basis for the industrial purification of Li-containing mother liquor.
研究领域:
能源与环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2023
·
IF 4.5
Zhihao Song,Qingkun Meng,Fuxiang Wei,Qing Yin,Yanwei Sui,Jiqiu Qi
Cobalt-based metal–organic framework (MOF) is commonly used as templates to prepare layered double hydroxides (LDHs) with specific morphology to improve the pseudocapacitance capacity. A multi-step synthesis method was employed in the reported work to introduce a second metal during the preparation process of bimetallic LDH materials. Herein, we disclosed a facile and efficient one-step in-situ hydrolysis strategy to prepare CoNi-LDH under mild condition using CoNi-MOF precursor, which introduces Ni element in the Co-MOF nucleation process. The method for synthesizing CoNi-LDH with nanoflower structure can omit the past time-consuming synthesis process and the complex modification process. The obtained CoNi-LDH at 60 °C achieves specific capacitance as high as 1634.1F g −1 at a current density of 1 A g −1 . The assembled CoNi-LDH-24//RGO ASC deliver high energy density of 48.97 Wh kg −1 at the power density of 787.16 W kg −1 , and the capacitance retention after 10,000 cycles can reach 81.7%. This work provides a mild and simple method to synthesize 3D structure LDH materials with excellent supercapacitor performance, and further confirms that the in-situ hydrolysis method is feasible and promising in the preparation of 3D CoNi-LDH nanoflowers.
研究领域:
材料科学
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能源存储与转换
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产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 12
·123504
·
IF 4.316
Yuan Du,Liu Hao,Wang Zixuan,Wang Xi,Miao Guirong,Wu Xu
β-PbO2 is an important high oxygen overpotential anode coating material. Further study on nanoscale β-PbO2 with higher performance and lower cost is a critical issue in order to develop the electrochemical ozone generator. Herein, an improved β-PbO2 nanoparticles synthesizing strategy based on the traditional Pb(OAc)4 hydrolysis method is proposed in this work, which is more scalable for industrial-scale production compared with existed nano β-PbO2 synthesizing methods. The possible mechanism of synthesizing β-PbO2 nanoparticles via Pb(OAc)4 hydrolysis was discussed for the first time. Based on the proposed mechanism, the size and morphology of the β-PbO2 nanoparticles were effectively controlled, and alternative raw material that can significantly reduce costs was developed. SEM, TEM, XRD, and XPS results indicate that pure phase β-PbO2 nanoparticles range from 10–30 nm were obtained. In addition, the use of alternative raw materials reduces the cost by 90%–95% compared to the traditional Pb(OAc)4 hydrolysis method. The β-PbO2 nanoparticles showed good ozone generation performances. The energy consumption per unit ozone of the β-PbO2 nanoparticles is reduced by 51.9% at the optimized operation condition than the reference PbO2 particles used for comparison.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
MATERIALS LETTERS
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2023
·
IF 3
Jiaxin Fu,Jin Hu,Yamin Lv,Lidan Miao,Kaizhao Wang,Jiale Wu,Kaijun Wang,Weijun Zhang
Gallium oxide (Ga 2 O 3 ), a promising semiconductor material, has attracted significant attention in recent years. This study focuses on a method for rapidly obtaining high-purity Ga 2 O 3 through the one-step hydrolysis of gallium in an alkaline environment to address the challenges of complex experimental equipment and the high-pressure condition of the traditional method. Uniformly dispersed rod-like GaOOH with a length of 2 µm is prepared using a 5 mM polyvinylpyrrolidone solution. Additionally, Ga 2 O 3 (500 °C α-Ga 2 O 3 and 800 °C β-Ga 2 O 3 ) with different crystal forms is prepared by calcinating GaOOH at different temperatures. Compared with conventional methods, this approach offers a fast, safe, and cheap process for preparing high-purity Ga 2 O 3 .
研究领域:
材料科学
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无机化学
·
半导体材料
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纳米材料
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功能材料
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DOI
高影响因子
FOOD CHEMISTRY
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2024
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IF 8.5
Yonglin Li,Yancai Li,Yan Guo,Jie Qiang,Yongsheng Cao,Guoyi Qu,Yuan Gao,Qi Li,Xiuzhu Yu
Chloropropanol esters are major contaminants in food, but their formation during traditional Chinese cooking remains unclear. In this study, a method based on lipase hydrolysis pretreatment was developed and validated to determine 4 chloropropanol esters. The formation of these esters during stir-frying and hotpot cooking under various conditions was investigated. The results showed that the proposed method outperformed the fast alkali-catalyzed transesterification method. Higher NaCl concentrations led to increased formation of chloropropanol esters. Chloropropanol esters decreased with increasing cooking time due to degradation. Refined oils with a higher ratio of unsaturated fatty acids produced more chloropropanol esters. Adding NaCl at the beginning or end of cooking resulted in fewer chloropropanol esters. Free radicals contribute to the chloropropanol esters, resulting in a strong correlation between chloropropanol esters, the peroxide value, and total polar compounds. This study provides valuable insights into the formation of chloropropanol esters and their mitigation during cooking.
研究领域:
食品科学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Hao Zhang,Junyan Wang,Minjie Liu,Di Liu
Cu/Al 2 O 3 catalyst was developed by a double hydrolysis precipitation. Over the Cu/Al 2 O 3 catalyst, a continuous mode of N-methylations of nitroarenes with methanol was successfully achieved under the exogenous base- and H 2 - free condition. Methylation process of nitroarenes could be controlled just by adjusting reaction conditions, affording the desired N-monomethylanilines or N, N-dimethylanilines, respectively. The characterization displayed that the double hydrolysis precipitation method made active metal Cu surface enrichment and high dispersion, meanwhile endow Cu/Al 2 O 3 with more developed pore system, which were responsible for the higher performance of our catalyst relative to Cu/Al 2 O 3 -CP. Compared with the reported batch mode, our procedure possessed the merits of low cost, environment-friendliness, better controllability and wide universality.
研究领域:
催化化学
·
绿色化学工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Zhengda Lin,Yijun Liu,Zhongming Zhang,Jie Yao
In this study we used a high-temperature steam-induced hydrolysis method to obtain a fluorinated OH/SiO 2 -TiO 2 /polyethersulfone (PES) composite hollow fiber membrane for CO 2 capture. The purpose of grafting SiO 2 and TiO 2 on the surface of PES by hydrolyzing silicon precursors and titanium precursors at high temperature, is to improve the alkali corrosion resistance and hydrophobicity of the PES membrane. The OH/SiO 2 -TiO 2 /PES composite hollow fiber membranes prepared by the high-temperature steam-induced hydrolysis method and the graft coating method were measured by SEM, EDS , FTIR, WCA, AFM , XRD and XPS in order to characterize the morphology and structure of the prepared membranes. In the CO 2 /CH 4 separation performance test experiment, the OH/SiO 2 -TiO 2 /PES membrane prepared by the high-temperature steam hydrolysis method showed better separation performance than the original PES membrane. The effects of absorbent flow rate, absorbent concentration and feed gas flow rate on CO 2 flux and CO 2 /CH 4 were selectivity investigated. When the flow rate of the absorbent (DEA) reached 16 L/h, the flow rate of the feed gas (CO 2 /CH 4 = 40 : 60) was 30 ml/min, the concentration of the absorbent was 1 mol/L, The CH 4 concentration was 99.88 % and the optimal separation factor was as high as 554.89. In general, the results obtained in this work may provide promising insights into the use of fluorinated OH/SiO 2 -TiO 2 /PES composite membranes for carbon capture and CO 2 /CH 4 separation in GLMC application.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
CELLULOSE
·
2024
·
IF 4.9
Zhao Junchai,Chen Long,Zhou Wentao,Zhao Pengbo,Peng Zheng,Lin Xiaobo,Yang Jinhui
Here, a facile method to extract the carboxylated cellulose nanocrystals (CNCs) with high yield from microcrystalline cellulose (MCC) at room temperature (RT) is put forward that uses a solvent system of zinc chloride (ZnCl 2 ) and citric acid (CA) aqueous solution. The rod-like carboxylated CNCs were achieved with a maximum yield of 72.3% and a maximum carboxyl group content of 0.75 mmol/g. Meanwhile, the crystal transformation from cellulose I to II was detected with variation of solvent composition. In addition, to the best of our knowledge, this is the first time that the iridescent phenomenon was observed in extremely thin films which were prepared from carboxylated CNC suspension with a concentration of only 0.08–0.15 wt% via evaporation-induced self-assembly. The possible formation mechanism is considered to be related to the synergistic effects of film confinement and drying stresses. Furthermore, the interaction between Petri dish substrate and the film played a role. As the first example of isolation of carboxylated CNCs with high yield at RT using ZnCl 2 /CA aqueous solution, this work provides a facile and practical strategy for the preparation of functional cellulose nanomaterials.
研究领域:
材料科学
·
纳米技术
·
化学工程
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2025
·
IF 4.5
Nanqing Zhang,Xianhua Bian,Zhenglong Zhu,Xin Huang,Ping-an Yang
To effectively absorb electromagnetic waves and reduce the impact of electromagnetic radiation on the health of residents and the normal operation of electronic devices, core-shell nanocomposite fibers (Fe NWs@SiO 2 @Ag) were successfully prepared by the liquid-phase hydrolysis method. The microwave absorption properties of core-shell nanocomposite nanofibers with different ratios were tested and analyzed using the coaxial method. The results show that the sample with a molar ratio of Fe:SiO 2 :Ag of 1:0.1:1 has the best comprehensive performance. This sample exhibits excellent microwave absorbing performance. When the mass filling fraction is 25 wt%, its minimum reflection loss (RL min ) can reach −61.55 dB, and the effective absorption bandwidth (EAB) can reach 3.52 GHz. The excellent microwave absorbing performance can be attributed to the interfacial polarization effect of the core-shell nanocomposite structure, the magnetic loss and conduction loss of each layer of materials, and the small-scale effect caused by the one-dimensional structure. This study can provide a methodological reference for the preparation of high-performance absorbing materials.
研究领域:
材料科学
·
纳米技术
·
电磁学
·
微波工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Guotao Lin,Yining Chen,Qi Lei,Qingge Feng,Qihua Liang,Guo-Dong Li
Developing high-performance formaldehyde sensors is crucial for safeguarding human health, given formaldehyde’s prevalence as a hazardous indoor volatile organic compound. However, formaldehyde sensors have struggled to meet demand in terms of operating temperature, selectivity, and detection limits, especially for ppb-level formaldehyde detection. Herein, Co-doped In 2 O 3 microspheres were synthesized by solvothermal methods combined with hydrolysis methods. The introduction of heterovalent cobalt metal can generate more oxygen vacancies of In 2 O 3 , enriching its surface active sites and optimizing its surface chemisorbed oxygen, thus effectively enhancing the formaldehyde sensing performance. The experimental results show that Co doping significantly enhances the formaldehyde sensing performance of In 2 O 3 , in which the optimal Co-doped In 2 O 3 ratio (S2) based sensor exhibits an exceptionally high response (R a /R g = 1342 ± 64) to 100 ppm formaldehyde at 90 ℃, about 13.8 times greater than the pure In 2 O 3 -based sensor. Additionally, it features a rapid response (≈ 2 s), excellent selectivity, and an ultralow detection limit of 10 ppb. The enhanced formaldehyde detection performance primarily arises from cobalt’s catalytic activity, the increase in specific surface area, and the increase in oxygen vacancies, which optimize the surface chemisorbed oxygen.
研究领域:
材料科学
·
化学传感器
·
环境监测
·
纳米技术
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）