JOURNAL OF ORGANOMETALLIC CHEMISTRY
·
2025
·
IF 2.4
Ke Yang,Sisi Cheng,Shijia Li,Kun Zhu,Ziqin Yao
The influencing factors of ZIF-8 synthesis were systematically investigated by the green synthesis method and the samples were also compared with ZIF-8 synthesized in other ways, and an optimal synthesis route was found by exploring the synthesis conditions. On this basis, the synthesis mechanism of ZIF-8 was analyzed. The research results show that the key influencing factors in the reaction process are the amount of NaOH and the pH value of the system. Different amounts of NaOH will produce different intermediates, and these intermediates further affect the pH value of the entire reaction system. The pH value of the system plays a decisive role in the deprotonation process of the ligand in the reaction, and this process is the key to whether the ZIF-8 structure can be formed. It is worth mentioning that the ZIF - 8 synthesized in this study demonstrates varying removal performances for different dyes under different conditions. Under specific conditions, it exhibits the maximum removal rate for Rhodamine B (RhB), reaching 99.97 %. This excellent removal performance is closely associated with the pore - structure characteristics of the synthesized material, which fully indicates that the ZIF - 8 synthesized through the green route has certain application potential and promising application prospects in related fields.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Xiheng Kang,Yun-Yan Wang,Shuangfei Wang,Xueping Song
One of the key issues in the development of biofuels using lignocellulosic feedstocks is to increase the yield of fermented sugar, and simultaneously decrease the generation of fermentation inhibitors. Therefore, it is essential to understand the degradation mechanism of xylan during hot-water pretreatment. We analyzed the hydrothermal degradation products of xylan and xylose under different conditions. Results showed that furfural and formic acid formed from xylose reached a maximum value of 32.56 % and 35.14 %, respectively. By increasing the initial pH of the xylan solution, the furfural concentration can be reduced effectively to 2% and the formation of formic acid was preferred under alkaline conditions. On this basis, we proposed a new hydrothermal degradation pathway of xylan in alkaline solution. The in-depth understanding of xlyan degradation during hot water pre-treatment will be beneficial for improving the efficiency of biofuel production.
研究领域:
生物能源
·
化学工程
·
植物学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 6
·1-10
·
IF 5.479
Li Bo,Ma Hong,Zhang Bo,Qian Jing,Cao Ting,Feng Haitao,Li Wu,Dong Yaping,Qin Wenwu
The authors describe the preparation of carbon dots (CDs) that display both blue (~ 410 nm) and yellow (~ 565 nm) emission peaks. The CDs was synthesized by solvothermal treatment of o-phenylenediamine in aqueous ethyl alcohol at pH ~7.0. The CDs are shown to be useful fluorescent probes for pH values in that the ratio of fluorescences at 565 and 410 nm strongly depends on the pH value in the range from 4.5–6.5 and 10.0–13.0, respectively. The blue fluorescence is quenched by 91% by 100 µM solutions of Hg(II) through an electron transfer process, and is restored by 97% an addition of chloride (0.5 mM). The yellow fluorescence, in contrast, is hardly affected. The ratio of fluorescences at 414 and 565 nm drops linearly in the 30 to 60 μM of Hg(II) concentration range, and the limit of detection is 60 nM. Fluorescence is linearly restored in the 70 to 180 μM chloride concentration range, and the LOD is 2.8 nM. Both the blue and the yellow emission are reduced by Cr(VI) (chromate) due to an inner filter effect at pH 3.0. The ratio of fluorescences (410/565 nm) drops linearly in the 20 to 250 μM Cr(VI) concentration range, and the LOD is 260 nM. The method was utilized to analysis of chloride in salt lake brine and of Cr(VI) in spiked tap water.
Schematic presentation of carbon dots with pH-dependent dual emission (at ~ 410 nm and ~ 565 nm). They are shown to be viable fluorescent probes for ratiometric sensing of pH values, mercury(II), chloride and Cr(VI) via different mechanisms.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jianjun Lian,Heli Wang,Hongping He,Weilin Huang,Mei Yang,Yin Zhong,Ping’an Peng
Iron sulfide (FeS) is an important scavenger for hexavalent molybdate (Mo(VI)) in an anoxic environment; it plays a crucial role in the mobilization and transformation of Mo(VI), although the underlying reaction mechanisms between Mo(VI) and FeS remain unclear. This study investigates the Mo(VI) reaction kinetics with the amorphous FeS over a pH range 5.0–9.0 and Mo’s chemical form on the FeS surface. It is found that the Mo(VI) reaction kinetics with FeS follow a pseudo first-order model, and the reaction rate constant ( k obs ) increases with a decrease in the pH value. The k obs at pH 5.0 is 0.027 min −1 , which is about 38 times higher than that at pH 9.0. The rapid Mo(VI) removal under acidic conditions is due to quick Mo(VI) transformation into stable MoS 2 and thiomolybdate (Mo V O x S y ). The amount of MoS 2 formed on the surface of FeS increases with a decrease in the pH value. Under neutral and alkaline conditions, Mo(VI) is not transformed into MoS 2 by FeS because the precipitation of iron oxy-hydroxide passivates the active sites of FeS. The study also investigates the effect of the initial dosage of FeS (20–200 mg L −1 ) and Mo(VI) (10–50 mg L −1 ) on the reaction kinetics of Mo(VI) with FeS. The results provides important information on the environmental fate of Mo(VI) in the anoxic environment containing amorphous FeS.
研究领域:
环境科学
·
地球化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CLAYS AND CLAY MINERALS
·
2019
·Vol. 67
·期 4
·275-282
·
IF 1.835
Liu Xiaonan,Zhang Youkui,Bian Liang,Li Jinshan
The adsorption of bovine serum albumin (BSA) protein is important for protein research but remains a great challenge. Here, the hydrothermal method and calcination in a hydrogen-argon mixed atmosphere were used to obtain ordered mono-crystalline magnetic Fe 3 O 4 nanorings with controllable size and uniform structure, which were applied to the adsorption of BSA protein. The results showed that the magnetic Fe 3 O 4 nanorings prepared have the advantages of good crystallinity, controllable morphology, and excellent magnetic response. The Fe 3 O 4 nanorings had an outer diameter of ~160–180 nm, inner diameter of ~80–110 nm, and height of 70 to ~110 nm. The amount of BSA adsorbed by magnetic Fe 3 O 4 nanorings increased with increasing protein concentration; when the concentration of BSA was ~2.75 mg·mL -1 the adsorption amount approached saturation. When the pH value of the solution was ~5, the Fe 3 O 4 nanorings absorption of BSA was greatest. With increasing adsorption time, the amount adsorbed increased gradually. Adsorption equilibrium was reached after 3 h. According to the formula, the saturated adsorption capacity of BSA per gram of magnetic Fe 3 O 4 nanorings was 325.2 mg.
.
研究领域:
生物化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2019
·
IF 2.8
Ali Aghababai Beni,Akbar Esmaeili
Common methods for removing heavy metals have numerous drawbacks, including low efficiency and high costs. In the biosorption of heavy metals, ions biosorbed on surfaces and active sites of biosorbents. In this paper, the relationship between the factors (pH, temperature, biosorbent dosage, retention time and Functional groups) and removal efficiency has been investigated. The purpose of this work is to introduce optimal conditions for biosorption reaction. Also, by introducing various types of biosorbents, expressed the advantages and method of preparation for each one. In various papers, not all biosorption isotherm models have been mentioned, there are described various types of biosorption isotherm, kinetics and thermodynamics models and important process data is set up for quick access to the tables.
研究领域:
环境科学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
TETRAHEDRON
·
2014
·
IF 2.817
Shouhai Yang,Wenge Yang,Qirun Guo,Tuan Zhang,Keyi Wu,Yonghong Hu
A simple but highly selective coumarin-based fluorescence probe 1 , 8-(1,3-dithiane)-7-hydroxycoumarin was designed and synthesized for both the ratiometric detection of Hg 2+ and the on–off response to pH change in aqueous solution. The sensor detected Hg 2+ selectively via Hg 2+ -promoted thioacetal deprotection reaction within five minutes and reflected pH in the range from 7.8 to 11.9 as a result of the equilibrium between weak-fluorescent acid form and strong-fluorescent base form. In addition, the probe has an excellent selectivity towards Hg 2+ over other competitive metal ions for biomedical and environmental applications. The sensing behavior of our probe was studied by UV–visible absorption spectra and fluorescence spectra .
研究领域:
分析化学
·
环境科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2016
·
IF 2.101
Feng-Fei Pang,Sen Li,Wen-Quan Sun,Guo-Zhi Han
We report the reversible conductivity and morphology modulation of PEDOT:PSS composites based on pH. Through studying effects of pH on the morphology and conductivity of PEDOT:PSS composites, it was found that different pH of PEDOT:PSS composites solution will result in different morphology of PEDOT:PSS composites film . At the same time, conductivity of the film also changed accordingly. With the increase of pH from 3 to 11, the microstructure of PEDOT:PSS film reversibly changed from a continuous network to non-continuous clusters, and the corresponding conductivity decreased from 0.62 S/cm to 0.42 S/cm. Furthermore, the mechanism was innovatively investigated by Raman spectra , along with UV–Vis spectra and SEM .
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2018
·Vol. 32
·期 7
·e4411
·
IF 3.581
Xin Jin,Guangrong Liu,Chongzhuo Bao,Mingxin Chen,Qiang Huang
The high dispersion and stability of a nanocomposites suspension are required as a crucial factor in many of their applications. In this study, ZnO nanosheets covered with polyaniline (PANI) thin layer (ZnO@PANI) were synthesized by a simple in-situ polymerization. The as-prepared ZnO@PANI powders were well characterized by XRD, Raman, FTIR, XPS and photoluminescence spectra, as well as SEM and TEM techniques. The effect of PANI incorporation on the chemical dissolution and dispersing stability of ZnO aqueous suspension was investigated. Dissolution experiments showed that the dissolution of ZnO was effectively restrained by the surface-hybridized PANI layer. ZnO@PANI suspension can be more stable in a wider pH range. Dynamic Light Scattering (DLS) analysis indicated that ZnO@PANI particles were thoroughly dispersed in the neutral and alkaline solution as proven by the emergence of a single distribution with a high diffused intensity. Sedimentation experiments suggested that ZnO@PANI suspension was a more stable dispersion taking into account the effect of pH and ionic strength.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Baodong Mao,Bo Wang,Furong Yu,Kewei Zhang,Zhengyuan Zhang,Jinhui Hao,Junbo Zhong,Yanhong Liu,Weidong Shi
In this paper, a facile hydrothermal synthetic strategy was developed for MoS 2 nanoflowers with enlarged interlayer spacing on the carbon cloth (CC) as a high efficiency cathode electrode for hydrogen evolution reaction (HER) under wide pH condition . It was observed that the loading amount of MoS 2 has a major impact on the HER performance, where the optimized MoS 2 /CC exhibited a low onset potential of 94 mV and a small Tafel slope of 50 mV dec −1 in strong acid solution (pH = 0). The improved HER performance can be contributed to the enlarged interlayer spacing, abundant defects and more exposed active sites in the small size MoS 2 nanosheets as revealed by XRD and HRTEM. Meanwhile, it also exhibited relatively good performance for HER under basic and neutral conditions with the overpotentials of 188 (pH = 14) and 230 (pH = 7) mV to achieve current density of 10 mA cm −2 and the Tafel slopes of 52 and 84 mV dec −1 , respectively.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Lei Liu,Shi-Zhong Luo,Bin Wang,ZhanHu Guo
The interactions between poly(acrylic acid) (PAA) and alumina have been widely investigated. In this study, the pattern of small molecular weight PAA ( M W 3000) interaction with γ-alumina has been dissected. The alumina/PAA hybrids were prepared at pH 4.0, 5.5, and 7.0, respectively. Nitrogen absorption–desorption analysis, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and elemental analysis were conducted to illustrate the characteristics of the hybrids. At pH 4.0, the coiled PAA conformation yielded polymer adsorption primarily on alumina outer surface. At higher pH values, the more stretched PAA molecules were able to infiltrate inside the alumina pores. The phenomenon is explained by the polymer chain reptation motion model. Coiled polymer chains are not oriented enough to penetrate the oxide pore channels. In contrary, stretched polymer chains are more likely to move along the pore channels.
研究领域:
材料科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2015
·
IF 4.529
Lijuan Feng,Shuang Zhao,Shenglei Sun,Wenyu Wang,Baoyu Gao,Qinyan Yue
The influences of solution pH on coagulation/ultrafiltration (C–UF) process were investigated by using three purified Al species of polyaluminium chloride (PACl). A series of online-simulation experiments were developed to assess the coagulation removal efficiencies (turbidity, UV 254 ), floc properties and membrane fouling in this paper. The results showed that change of pH had a significant impact on coagulation efficiencies, floc properties, membrane flux as well as the whole process. Under acidic condition, the hydrolysis action of aluminum salts was restrained which is bad for charge neutralization. While under alkaline region, absorption was the dominant mechanism to combine HA–Kaolin. Meanwhile, HA is apt to soluble by deprotonating under alkaline region which is hard to remove. These common effects made the experiment results complex. HA removal efficiency of Al a and Al b were higher than that of Al c , but the turbidity removal by Al c was slightly higher under the same pH condition. Flocs generated by Al a at pH 6 had advantages such as larger size and the most loosely structure which contributed the most to alleviating membrane fouling. Membrane fouling with Al b and Al c in alkaline range was more serious than that in acidic range.
研究领域:
环境科学
·
水处理工程
✓ 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）