作者机构:
[Liu, Dongbo; Zhang, Zhixu] State Key Lab Subhlth Intervent Technol, Changsha 410128, Hunan, Peoples R China.;[Liu, Dongbo; Zhang, Zhixu] Hunan Agr Univ, Coll Hort, Changsha 410128, Hunan, Peoples R China.;[Qin, Dan] Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410128, Hunan, Peoples R China.;[Guo, Xin] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.;[Lin, Haiyan] Natl Res Ctr Engn Technol Utilizat Ingredients Bot, Changsha 410128, Hunan, Peoples R China.
通讯机构:
[Guo, X ] C;Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.
关键词:
Adsorption;Carbon dots;Pb(II);Starch
摘要:
The adsorption removal of lead (Pb) ions has become a crucial area of research due to the potential health hazards associated with Pb contamination. Developing cost-effective adsorbents for the removal of Pb(II) ions is significantly important. Hence, a novel fluorescent starch-based hydrogel (FSH) using starch (ST), cellulose nanofibrils (CN), and carbon dots (CD) was fabricated for simultaneous adsorption and detection of Pb(II). A comprehensive characterization of FSH, including its morphological features, chemical composition, and fluorescence characteristics, was conducted. Notably, FSH exhibited a maximum theoretical adsorption capacity of 265.9mg/g, which was 13.0 times higher than that of pure ST. Moreover, FSH was employed as a fluorescent sensor for Pb(II) determination, achieving a limit of detection (LOD) of 0.06μg/L. An analysis was further performed to investigate the adsorption and detection mechanisms of Pb(II) utilizing FSH. This study provides valuable insights into the production of a novel cost-effective ST-based adsorbent for the removal of Pb(II) ions.
摘要:
A novel cellulose nanofibril/titanate nanofiber modified with CdS quantum dots hydrogel (CTH) was synthesized as an effective, stable, and recyclable photocatalytic adsorbent using cellulose nanofibril (CN), titanate nanofiber (TN), and CdS quantum dots. Within the CTH structure, CN formed an essential framework, creating a three-dimensional (3D) porous structure that enhanced the specific surface area and provided abundant adsorption sites for Cr(VI). Simultaneously, TN modified with CdS quantum dots (TN-CdS) served as a nanoscale Z-type photocatalyst, facilitating the efficient separation of photoinduced electrons and holes, further increasing the photocatalytic efficiency. The morphological, chemical, and optical properties of CTH were thoroughly characterized. The CTH demonstrated the maximum theoretical adsorption capacity of 373.3±14.2mg/g, which was 3.4 times higher than that of CN hydrogel. Furthermore, the photocatalytic reduction rate constant of the CTH was 0.0586±0.0038min(-1), which was 6.4 times higher than that of TN-CdS. Notably, CTH displayed outstanding stability, maintaining 84.9% of its initial removal efficiency even after undergoing five consecutive adsorption-desorption cycles. The remarkable performance of CTH in Cr(VI) removal was attributed to its 3D porous structure, comprising CN and TN-CdS. These findings provide novel insights into developing a stable photocatalytic adsorbent for Cr(VI) removal.
摘要:
Hydrogel, a common carrier of photocatalyst that suffers from compromised catalytic efficiency, is still far from practical application. Herein, based on "computer chip-inspired design", a novel nanocellulose/carbon dots hydrogel (NCH) was fabricated as superior intensifier instead of common carrier of sodium titanate nanofibre (STN), where carbon dots (CDs) enhanced amino group-induced adsorption for Cr(VI), promoted photocatalytic properties of STN via transferring the photogenerated electron-hole pairs and improved amino group-induced desorption for reduced product (Cr(III)) via electrostatic repulsion, showing an efficiency of 1+1>2. Adsorption and photocatalysis experiments demonstrated superior removal performance of the NCH incorporating STN, as shown by theoretical maximum adsorption capacity of 425.74mg/g and kinetic constant of 0.0374min(-1) in the photocatalytic process, which was nearly 6.6 and 7.3 times of STN. A series of experiments was conducted to confirm the novel mechanism of CDs-enhanced adsorption-photocatalysis-desorption synergy. This work not only provides new insights into the fabrication of a superior intensifier for nanosized photocatalyst, but also proposes one new mechanism of CDs-enhanced adsorption-photocatalysis-desorption synergy, which is helpful for designing and optimizing nanosized photocatalyst.
通讯机构:
[Qiu, XY; Guo, X ; Li, XJ ] C;Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Peoples R China.;Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.
关键词:
Wood;Adsorption;Tetracycline
摘要:
The antibiotic contamination in water is a growing environmental concern, which prompts the need for an efficient and nontoxic adsorbent to eliminate antibiotics from water. Tetracycline (TC) is a widely used antibiotic owing to its low cost and high effectiveness, which adds to significant environmental impact. In this paper, we present a novel non-cytotoxic fluorescent wood (NCFW) with remarkable properties, including a high TC adsorption capacity (up to 99.17 mg/g), good selectivity and sensitivity for TC detection, favorable fluorescence (absolute quantum yield of 3.9%), and noncytotoxicity (cell viability of more than 90%). Our results revealed the unique structure of the NCFW as a framework for improving the adsorption capacity, whereas the fluorescent probes can act as effective sensors for detecting TC. These findings indicate that the NCFW has the potential to be a promising adsorbent for removing TC from wastewater.
期刊:
International Journal of Biological Macromolecules,2023年233:123566 ISSN:0141-8130
通讯作者:
Xin Guo<&wdkj&>Yiqiang Wu
作者机构:
[Peng, Junwen; Zhang, Xuefeng; Guo, Xin; Qi, Xinmiao] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Peoples R China.;[Huang, Yong] Nanjing Forestry Univ, Coll Mat Sci & Engn, Joint Int Res Lab Biomass Energy & Mat, Nanjing 210037, Peoples R China.;[Qiao, Jianzheng; Wu, Yiqiang] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Guo, Yucong] Chinese Acad Sci, CAS Res Educ Ctr Excellence Mol Sci, State Key Lab Struct Chem Unstable & Stable Specie, Beijing Natl Lab Mol Sci BNLMS,Inst Chem, Beijing 100190, Peoples R China.
通讯机构:
[Xin Guo; Yiqiang Wu] C;College of Science, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
关键词:
Carbon dots;Hydrogel;Nanocellulose
摘要:
A novel nanocellulose/carbon dots hydrogel (NCH) was fabricated using cellulose nanofibrils (CN), carbon dots (CD) and zinc oxide (ZnO)/silver bromide (AgBr) nanocomposite, where CD enhanced amino group-induced adsorption of hexavalent chromium (Cr(VI)) and promoted the photocatalytic properties of ZnO/AgBr nanocomposite via the transfer of photogenerated electrons, resulting in enhanced efficiency in the removal of Cr(VI) from aqueous solution. The structure, morphology, and physicochemical properties of the prepared NCH were characterized, with the results of adsorption and photocatalysis experiments showing the maximum theoretical adsorption capacity of the NCH to be 315mg/g, 219 times that of the ZnO/AgBr nanocomposite; the apparent removal rate constant of the NCH was 0.0319min(-1), 11.7 times that of the ZnO/AgBr nanocomposite. Furthermore, the removal performance of NCH was attributed to CD-enhanced synergistic adsorption and photocatalysis effects, supported by characterization and experimental results. This work provides insight into the design and fabrication of a novel adsorptive photocatalyst with CD-enhanced synergistic adsorption and photocatalysis effects for removing Cr(VI) from aqueous solution.
期刊:
Journal of Environmental Chemical Engineering,2022年10(6):108621 ISSN:2213-3437
通讯作者:
Jianzheng Qiao<&wdkj&>Xin Guo
作者机构:
[Ren, Tingting; Peng, Junwen; Yang, Guanhua; Guo, Xin; Liu, Zhihuan; Yuan, Hanmeng] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Peoples R China.;[Qiao, Jianzheng; Wu, Yiqiang] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.
通讯机构:
[Jianzheng Qiao; Xin Guo] C;College of Science, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
关键词:
Wood;Divalent mercury;Adsorption
摘要:
Divalent mercury [Hg(II)] is a global pollutant affecting human health and the ecosystem. The effective treat-ment of Hg(II) necessitates materials that display high performance and nontoxic adsorption. In this work, we present a facile method of fabricating a nontoxic fluorescent wood (NFW) with reconstructed porous structure and increased sorption sites towards the selective detection and efficient removal of Hg(II). The major advantage of this method is that the natural skeleton from wood is not completely destroyed and smashed to a nanometre size, saving energy and time and reducing the need for specific equipment. The obtained NFW also exhibits strong adsorption ability (theoretical maximum adsorption capacity: 128.6 mg/g), excellent sensitivity for Hg(II) detection (limit of detection: 0.54 mu g/L) and no cytotoxicity (cell viability: above 90%). The cost analysis shows that the NFW is inexpensive compared to activated carbon for Hg(II) sorption. This work provides a facile technique for developing low-cost, multifunctional and nontoxic adsorbents using original wood.
摘要:
For getting a better understanding of molecular association between water and wood, molecular structure of desorbed water in a typical wood (i.e. heat-treated wood) during moisture desorption process was investigated using micro-FTIR spectroscopy. Spectra were collected in the relative humidity (RH) region from high level to low level. A qualitative analysis of these spectra and corresponding difference spectra confirmed moisture sorption sites and determined main spectral region affected by moisture sorption. In addition, from component peak analysis of the identified spectral region of difference spectra, three component peaks were attributed to three types of bound water. Based on change of bound water against RH, the entire moisture desorption process of heat-treated wood could be separated to three parts. Moreover, molecular structure of desorbed water in these three parts was demonstrated, separately.
摘要:
As many properties of lignin are relied on moisture content, water adsorption is very important for its product performance. To better understand water adsorption mechanism of lignin, the molecular interactions between adsorbed water and lignin was studied using micro-FTIR spectroscopy. Spectra of lignin were collected at various relative humidity (RH) levels from low to high. From qualitative analysis of these spectra and corresponding difference spectra, water adsorption sites of lignin was recognized, and the spectral ranges closely related to water adsorption were identified. Further, from component peak analysis of the identified spectral region, three component peaks were attributed to three types of bound water separately. Based on the change of bound water vs. RH, the moisture adsorption process of lignin could be separated to three parts. Moreover, molecular association of adsorbed water with lignin was all demonstrated in these three parts. (C) 2019 Elsevier B.V. All tights reserved.
期刊:
International Journal of Biological Macromolecules,2019年132:1106-1111 ISSN:0141-8130
通讯作者:
Guo, Xin
作者机构:
[Ma, Qiang; Xiao, Teng; Guo, Xin; Yuan, Hanmeng] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.;[Wu, Yiqiang; Xiao, Teng] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.
通讯机构:
[Guo, Xin] C;Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.
关键词:
Lignin;Micro-FTIR spectroscopy;Qualitative and quantitative analysis
摘要:
Moisture sorption has a great impact on the mechanical properties of lignin. To better characterize the moisture sorption of lignin, an approach for in situ qualitative and quantitative analysis of moisture adsorption in nanogram-scaled lignin by using micro-FTIR spectroscopy and partial least squares regression is introduced in this study. Spectra of nanogram-scaled lignin were collected within the relative humidity (RH) of 0%-92%. A qualitative analysis of these measured spectra confirmed the effective water sorption sites and determined spectral ranges related to moisture adsorption. Using these identified spectral ranges, a quantitative forecasting model for the moisture content (MC) of lignin was built and developed according to partial least square regression (R-2, 0.9996; RMSECV, 0.408; RMSEP, 0.118). Furthermore, the water sorption isotherm of lignin was acquired using the established forecasting model in which a very positive correlation between the estimated and measured MCs was demonstrated using a dynamic vapor sorption (DVS) setup. The results confirmed the practicability and effectiveness of this in situ qualitative and quantitative analysis approach. (C) 2019 Elsevier B.V. All rights reserved.
通讯机构:
[Wen, Ruizhi] C;Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.
关键词:
Teak wood (Tectona grandis Linn. fil.);discoloration;FTIR;GC-MS
摘要:
To investigate the discoloration behaviour of teak (Tectona grandis Linn. fil.) during irradiation, teak veneer specimens were exposed to xenon lamp light simulating sunlight for 80 h and subsequently analysed with a colorimeter. The colour changes were explained by recording Fourier transform infrared (FTIR) and gas chromatography-mass spectrometry (GC-MS) spectra at different exposure times. Forty hours of simulated irradiation marked a key point in the colorimetric analysis. During irradiation of 40 h, the increase in the CIELAB parameters Delta a* and Delta b* originated from the generation of carbonyl derivatives that were determined by FTIR analysis. Besides that, by combining GC-MS and microscopic analyses, the decrease in Delta L* in the first 20 h resulted from extractives migrating from the interior to the surface, and that the subsequent increase in Delta L* mainly arose from volatilization of the extractives. Additionally, the decrease in Delta b* after another 40 h of irradiation was mainly due to decreasing volatile extractive contents. Our conclusion reveals the causes of photo-induced discoloration in teak.
期刊:
Wood Science and Technology,2018年52(4):971-985 ISSN:0043-7719
通讯作者:
Wu, Yiqiang
作者机构:
[Wu, Yiqiang; Guo, Xin] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Guo, Xin] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410004, Hunan, Peoples R China.;[Yan, Ning] Univ Toronto, Fac Forestry, 33 Willcocks St, Toronto, ON M5S 3B3, Canada.
通讯机构:
[Wu, Yiqiang] C;Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.
摘要:
Heat modification is an effective method of reducing the hygroscopicity of wood. To gain a detailed understanding of water adsorption mechanism of heat-treated wood, the molecular interaction between the adsorbed water and heat-treated wood was studied via micro-FTIR spectroscopy. The micro-FTIR spectra of heat-treated wood exhibited a typical change in the chemical groups resulting from the heat treatment. In addition, the micro-FTIR spectra at different relative humidity levels confirmed the chemical sites at which the heat-treated wood adsorbed the water. A component band analysis of these difference spectra revealed three component peaks that were assigned to strongly, moderately, and weakly hydrogen-bonded water, respectively. Based on this variation of these three types of adsorbed water, the water adsorption process of heat-treated wood was divided into three different sections. Furthermore, the structure of the water adsorbed in these three sections was demonstrated. The results of this study provide a valuable insight into the state of water present in heat-treated wood.
作者机构:
[郭鑫; 吴义强; 李贤军] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China;[郭鑫] College of Sciences, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构:
College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, China
关键词:
wood;water distribution;existing states
摘要:
Wood-water relationship has been studied since the beginning of wood research. With the development of new technology,vast modern analytical method are emerging,and the study of wood-water relationship is changing from macro to micro scale and from cell to molecular level. The main objective of this paper was to review the modern analytical techniques which have been applied to study the wood-water relationship. This paper was divided into four parts. Firstly, the extremely heterogeneity of the wood cell wall structure and chemical composition and the highly complex states of water were discussed,and then the distribution and existing states of water in wood was summarized as an active field of the research about wood-water relationship. Secondly,the application of four kinds of analytical techniques,such as magnetic resonance imaging(MRI),computed tomography(CT),neutron imaging(NI) and vibrational spectroscopic imaging,in the study of water distribution were summarized. Meanwhile,the advantages and limitations of these four techniques were provided. Some of the latest research progress was: Vibrational spectroscopic imaging techniques such as micro-FTIR and confocal Raman could offer visual examination and spectral information of chemical functional groups in situ,and owned high spatial resolution on the micrometer length scale. The spatial resolution of micro-FTIR imaging technique was 6.25 μm by the instrumental parameters,and the spectral changes indicated that the adsorbed water concentration was nonuniform at the cell structure level. Meanwhile,the spatial resolution of confocal Raman imaging technique was higher than 1 μm,and the spectral changes indicated that the amount of water in the cell corner(CC) was less than that in the middle layer of secondary wall(S2) throughout the entire range of relative humidity(RH) levels. Thirdly,the recent advances in the application of four kinds of analytical techniques,such as near infrared(NIR) spectroscopy,nuclear magnetic resonance(NMR),fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy,were discussed in the study of existing states of water in wood. The advantages and limitations of these four techniques were also provided. Some of the latest research progress was: The micro-FTIR spectroscopy and a specially designed sample cell were used to examine the molecular association of adsorbed water with wood during adsorption process. It was confirmed that carboxyl CO,C—O groups as well as OH groups were active sites for water adsorption. Meanwhile,strongly,moderately and weakly hydrogen-bonded water molecules were identified and assigned. What's more,according to the variation trend of these hydrogen-bonded water molecules,three sections were divided for adsorption process. Furthermore,the existing states of water in each section was demonstrated as CO…(HOH) …OH or OH…(OH_2) …OH、WATER…HOH… WATER,and tetrahedral structure. Finally,some future research subjects in the research about wood-water relationship were proposed,such as applying new approaches with greater accuracy and higher resolution,developing the convincing component band analysis.
作者机构:
[李立君; 赵兵; 文韬; 张仟仟; 刘付] School of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, China;[郭鑫] School of Science, Central South University of Forestry and Technology, Changsha, China;[洪添胜] Division of Citrus Machinery, China Agriculture Research System, Guangzhou, China;[洪添胜; 文韬] Key Laboratory of Key Technology for South Agricultural Machinery and Equipment, Ministry of Education, Engineering College of South China agricultural University, Guangzhou, China
通讯机构:
Key Laboratory of Key Technology for South Agricultural Machinery and Equipment, Ministry of Education, Engineering College of South China agricultural University, Guangzhou, China
关键词:
模型;光谱检测;农业;霉变稻谷;脂肪酸;可见/近红外光谱;特征波段;样本集划分
摘要:
为了实现霉变稻谷脂肪酸含量无损、快速检测,该文研究应用可见/近红外光谱技术检测霉变稻谷的脂肪酸含量。考虑到直接选用霉变稻谷可见/近红外光谱数据构建脂肪酸含量预测模型存在建模费时、预测失准等问题,研究提出了霉变稻谷脂肪酸含量的可见/近红外优化校正模型。研究中通过光谱-理化值共生距离(sample set partitioning based on joint x-y distance, SPXY)算法结合偏最小二乘法初步分析了不同校正集样本预测霉变稻谷脂肪酸含量的差异;利用连续投影算法(SPA)提取了反映霉变稻谷脂肪酸含量变化的特征波段;采用偏最小二乘法(partial least square, PLS)和多元线性回归法(multivariable linear regression, MLR)分别建立了基于特征波段光谱反射值的霉变稻谷脂肪酸含量预测模型,并对比分析了采用SPXY样本集划分的模型预测效果。结果表明:采用SPXY法筛选出的65个校正集样本分布与初始校正集相近,脂肪酸含量变化范围为18.55~127.26 mg,其标准差为32.39;SPA算法最终从256个全光谱波段中优选出9个特征波段,实现了光谱数据的压缩;分别建立的SPXY-SPA-PLSR模型和SPXY-SPA-MLR模型预测霉变稻谷脂肪酸含量相关系数RP为0.922 1和0.915 9,预测均方根误差RMSEP为13.889 3和14.261 0;SPXY筛选校正集所构建模型预测精度与初始校正集所建模型相当,但校正集样本数量减少为初始校正集的41%,运算时长缩短为初始样本集的32%,提高了模型的校正速度。