JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2017
·
IF 3.255
Yan Ren,Juanjuan Zhao,Yanan Shi,Caiyun Chen,Xiangming Chen,Changjun Lv
L-Hydroxyproline (L-Hyp) is an important biomarker for idiopathic pulmonary fibrosis (IPF). The quantitative methods based on high-performance liquid chromatography coupled with fluorescence detection after pre-column derivatization typically requires complicated derivatization conditions and obtains unstable derivatives. Here, a novel derivatization reagent, 9-acetylimidazol-carbazole, was synthesized for the first time to efficiently and rapidly label the amino groups of L-Hyp. The high-performance liquid chromatography method with pre-column derivatization was performed on an Agilent ZORBAX SB-C 18 column (4.6 × 250 mm, 5 μm). The product was measured using fluorescence detection at excitation and emission wavelengths of 232 and 370 nm, respectively. The method was validated in specificity, linearity, limit of detection (66.7 fmol), limit of quantification (333.3 fmol), intra-day precision (0.75%), inter-day precision (3.82%), stability (3.15%), and recovery (90.7–109.4%). The validated method was successfully applied to the determination of L-Hyp in the lung tissues of healthy and IPF rats. The results showed that the concentration of L-Hyp (3.64 mg/g) in the IPF model was significantly higher than the concentration (2.33 mg/g) in the healthy control group with P < 0.01. This is a new method for the determination of L-Hyp and can be used for other amino acid-related studies in the future.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Ning Xie,Jinchao Han,Haowei Kang,Yiting Liu,Qiang Weng,Xingming Ning,Pei Chen,Xinbing Chen,Zhongwei An
Anion exchange membranes (AEMs) are crucial components of anion exchange membrane fuel cells (AEMFCs), and the development of highly efficient and stable AEMs is fundamental for advancing the practicality of AEMFCs. In this study, we propose the concept of “combining rigidity and flexibility” to design a series of poly(carbazole)-based AEMs with unique dual side chains. One side chain is a flexible dialkoxy chain, while the other consists of a rigid aromatic structure attached to two flexible alkyl chains. The resulting AEMs exhibit a remarkably high ionic conductivity, ranging from 120.2 to 175.7 mS cm–1 at 80 °C, along with an ion exchange capacity of 1.64–2.19 mequiv g–1. These properties are attributed to significant microphase separation facilitated by the strong interaction between the dual side chains. Furthermore, these AEMs demonstrated excellent alkaline stability. Even after being immersed in NaOH solution for 1080 h, their conductivity remains above 92%. This exceptional stability against hydroxide ions is attributed to the large electrostatic potential of the dialkoxy side chain, as verified by density functional theory calculations. Importantly, when incorporated into a hydrogen–oxygen fuel cell, the AEMs enable the fuel cell to achieve a large power density of 605 mW cm–2 at 70% relative humidity. This remarkable performance underscores their potential application prospects in the field of alkaline fuel cells. As a result, our findings contribute to the ongoing advancement of the AEMFC technology.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Ning Xie,Tao Wang,Haowei Kang,Yiting Liu,Xinli Li,Qiang Weng,Xingming Ning,Pei Chen,Xinbing Chen,Zhongwei An
High-performance anion exchange membranes (AEMs) have garnered increasing attention in recent years. However, commercial progress of the AEM for fuel cells is still hindered by its low ionic conductivity and inadequate alkaline stability. In this study, we propose the incorporation of a hydrophobic rigid-flexible coupled side chain into a polycarbazolyl AEM as an innovative approach to enhance both the conductivity and stability. The results demonstrate that the AEMs with hydrophobic rigid-flexible coupled side chains exhibit superior conductivity and stability compared with those without (PQMC-0). For example, the ion exchange capacity of PQMC-10 is reduced by 11% than PQMC-0, but its conductivity is enhanced by 14%, dimensional change is decreased by almost half, and oxidative stability is increased by more than four times. Improved conductivity of the AEMs can be attributed to the presence of hydrophobic rigid-flexible coupled side chains, making it easier for AEM to construct microphase separation to facilitate ion transport. Furthermore, the introduction of hydrophobic side chains reduces water absorption of the membrane, thereby enhancing its dimensional stability while minimizing the intake of free radicals or hydroxide ions present in water. Consequently, this modification significantly improves the oxidative and alkaline stability as well. Finally, the PQMC-10 shows a maximum power density of 649 mW cm–2 in a single fuel cell, which is three times bigger than that of PQMC-0, indicating a promising application in the field of fuel cells.
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2024
·
IF 10.7
Xi Wang,Xiao Meng,Tongtong Cui,Qian Hu,Bowen Jin,Yisheng He,Xingjun Zhu,Chunhong Ye
Room temperature phosphorescence (RTP) materials with wood as framework are highly desirable due to their extended afterglow , high haze and good mechanical properties, which is highly desired in lighting materials. However, it remains challenging to obtain wood-based RTP materials that possess on-demand afterglow colors while maintaining high transparency across the entire visible spectrum. In this study, long-persistent phosphorescent transparent composite with tunable afterglow color is fabricated by infiltrating delignified wood with phosphors (including carbazole , naphthalene , and pyrene) doped polymethyl methacrylate (PMMA). Such RTP woods indicate remarkable transparency, over 70 %, and an extended afterglow duration of up to 8 s. Here, PMMA serves as rigid surrounding to suppress the non-radiative transition of phosphors to ensure phosphorescence, and to fulfill in the wood lumen to match the refractive index of cellulose for transparency. By formulating phosphors with different types and concentration ratios, transparent woods with diverse phosphorescence colors, and white emission, are successfully achieved. Furthermore, the RTP woods demonstrate dynamically tunable afterglow colors over time based on the varied phosphorescent lifetimes. Characterized by their high transparency and tunable colors, these natural wood-based RTP materials have great potentials for application in the fields of LED materials, optics, and building materials.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Horticulturae
·
2024
·Vol. 10
·期 11
·1144
·
IF 3.1
Mostafa Saeed,Lan Zhao,Ahmed K. Rashwan,Ahmed I. Osman,Zhuyun Chen,Guoyun Wang,Chaochao Zhou,Ting Tu,Ahmed Alabd,Yun Jiao,Zhongshan Gao
Ethylene is an essential indicator of fruit ripening and climacteric or non-climacteric nature. This study investigated the postharvest behavior of five Chinese bayberry cultivars ‘Biqi’, ‘Dongkui’, ‘Fenhong’, ‘Xiazhihong’, and ‘Shuijing’. The fruits were harvested mature and stored at room temperature (25 °C) and under cold storage conditions (4 °C) to investigate the dynamics of ethylene production, firmness, anthocyanin content, and cell wall polysaccharide composition, as well as basic fruit physicochemical characteristics. The results show that Chinese bayberry is a climacteric fruit with ethylene production peaking shortly after harvest, especially at room temperature. Fruit color intensified over time due to anthocyanin accumulation, particularly in the flesh core. Darker cultivars produced more ethylene, which correlated with higher anthocyanin levels. At room temperature, ‘Biqi’ (black) had the highest ethylene production (4.03 µL·kg−1·h−1) and anthocyanin content (0.91 mg/g FW), while ‘Shuijing’, the white cultivar, had the lowest ethylene levels (1.9 µL·kg−1·h−1) and anthocyanin content (0.03 mg/g FW). Firmness significantly decreased at room temperature due to the degradation of hemicellulose and insoluble pectin, whereas cold storage mitigates this effect. After 3 days at room temperature, the average of firmness decreased by 23.7% in the five cultivars, compared to 12.7% under cold storage. Total soluble solids increase during storage, enhancing sweetness, especially at room temperature, with ‘Biqi’ increasing from 9.2 to 10.9% at 4 °C. Titratable acidity slightly decreased over time: the value for ‘Biqi’ decreased from 1.2% to 0.95% at room temperature and 1.1% at 4 °C. Citric, malic, and tartaric acid generally declined at room temperature but stabilized under cold storage. Sucrose, fructose, and glucose increased or remained stable, with significant varietal differences. Our results indicate that storing Chinese bayberry at 4 °C effectively preserves its quality and extends postharvest life. These findings underscore ethylene’s key role in regulating ripening, postharvest quality, and shelf life by influencing fruit color, firmness, and overall consumer appeal.
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2024
·
IF 2.8
Fu Xiaolei,He Yan,Guo Zhulei,Chen Mingfan,Du Wenlong,Zeng Yuqin,Yuan Dingzhong,Na Bing
In this work, we designed and synthesized two novel bi-heteroatom functionalized hyper-crosslinked porous polymers (HCP-CT and HCP-CF) through a simple one-step Friedel–Crafts alkylation reaction. The resulted polymers N/S bi-heteroatom functionalized polymer HCP-CT and N/O bi-heteroatom functionalized polymer HCP-CF both have good adsorption property for organic dyes such as methyl orange (MO) and methylene blue (MB) in aqueous solution due to its rich pore structure, high specific surface area and rich-heteroatoms of pore surface. It is worth mentioned that the maximum adsorption capacity ( q max ) of cationic dye MB by the porous polymer HCP-CT at room temperature was reached up to 1571.46 mg/g, which is much higher than that of most reported porous materials. Furthermore, the adsorption capacity of HCP-CT for the cationic dye MB was more than seven times that of the anionic dye MO ( q max = 212.77 mg/g). Also, the polymer HCP-CF for the MB adsorption capacity ( q max = 352.11 mg/g) was more than twice higher than that of anionic dye MO ( q max = 131.75 mg/g). The above trends may be because of the stronger electrostatic interaction between the negatively charged N-S/O bi-heteroatom of HCP-CT and HCP-CF with the cationic dye MB than that of MO. In addition, the removal percentage of polymers HCP-CT and HCP-CF still remained above 80% after five adsorption–desorption cycles. Hence, this work may provide a convenient synthetic route to develop a novel hyper-crosslinked polymer with high capacity for the entrapment of dyes from aqueous solution.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Wenli Ma,Lin Tian,Qingzhi Zhang,Lijian Shangguan,Fanghui Wang,Hong Zhu
To overcome the imbalance between high ionic conductivity, dimensional stability and strong alkali resistance in anion exchange membranes (AEMs), this work discarded the traditional polymer structure with cationic main chains, while prepared n-DTMA-PHCZBDO AEMs with different alkyl chain lengths by combining hydrophilic bi-cationic side chains and hydrophobic alkyl long side chains. The performance test results showed that membrane 6-DTMA-PHCZBDO has high ionic conductivity (169.2 mS cm -1 ), good dimensional stability (WU 140.3 %, SR 30.1 %) and excellent mechanical properties (55.3 MPa). Particularly, the ionic conductivity and tensile strength degradation rate of membrane 6-DTMA-PHCZBDO were less than 10 % after stabilization in 2 M NaOH at 80 °C for 2000 h, showing outstanding alkali resistance. Besides, It not only exhibited low resistance (R ohm 0.134 Ω cm 2 and R ct 0.035 Ω cm 2 ), high current density at 40 °C (1.00 A cm -2 ), 50 °C (1.83 A cm -2 ) and 60 °C (2.40 A cm -2 ) in 2.2V, but also showed good durability (degradation rate 1.71 mV h -1 , at 1000 mA cm -2 for 60 h) in anion exchange membrane water electrolysis (AEMWEs). Importantly, membrane 6-DTMA-PHCZBDO could be well realized for dual application of AEMWEs and fuel cells, which also had good H 2 -O 2 fuel cell power density (490.93 mW cm -2 ). Therefore, the hydrophilic and hydrophobic dual side linking branches can enhance the comprehensive performance of AEMs and can facilitate the application of it in AEMWEs and H 2 -O 2 fuel cell.
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Jian Lv,Yiwen Wang,Zhuyu Wang,Danni Shen,Qinggong Jia
Ternary high-nickel oxide exhibits a relatively high working voltage compared with traditional lithium battery cathodes (LiFePO4, etc.). Consequently, it has been widely studied in recent years and is at the forefront of research on positive electrodes for power batteries. To achieve higher reversible capacity, it is often necessary to increase the battery operating voltage. However, there are many drawbacks to this method, such as surface cracking of the working electrode and serious side reactions with the electrolyte. The novel dual-additive combination in this work has the potential to significantly address the aforementioned issues. A composite polymer cathode–electrolyte interface (CEI) film is formed on the surface of the cathode due to two aromatic compound additives preoxidation. The stable CEI film not only improves the stability of the electrode but also suppresses solvent and hydrofluoric acid (HF) to effectively inhibit the side reaction on the cathode surface. Furthermore, these two additives can be readily reduced at the anode to form a solid electrolyte interface (SEI) membrane containing rich LiN&LiF, which effectively suppresses the formation of lithium dendrites. The battery capacity retention could be up to nearly 83% on the dual-additive electrolyte compared to the baseline electrolyte after 300 cycles. This work may provide more possibilities for future research on high-voltage lithium batteries.
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2025
·
IF 6.7
Ning Xie,Haowei Kang,Yiting Liu,Chenhe Yao,Qiang Weng,Xingming Ning,Pei Chen,Xinbing Chen,Zhongwei An
As a core component of anion exchange membrane fuel cells (AEMFCs), the anion exchange membrane (AEM) has been severely affected by the “trade-off” effect between ionic conductivity and dimensional stability, as well as poor alkaline stability, which seriously limits the development of its commercialization. In this study, a novel polycarbazolyl AEM with large electronegative hydrophobic side chain (QPBC-HPO) was designed and prepared. The results demonstrated that the AEM QPBC-HPO showed a higher ionic conductivity of 156.8 mS cm −1 than that of the reference AEMs, which is attributed to the orientation of cationic groups driven by the large electronegative side chain, while this is conducive to the formation of a regular continuous ion transport channel in the membrane, supported by micromorphology characterization and theoretical calculation of molecular model. Additionally, the hydrophobic side chain contributed to proper water uptake and high dimensional stability in the AEM QPBC-HPO, mitigating the “trade-off” effect. Furthermore, the AEM QPBC-HPO exhibited higher alkaline stability with 85.5 % ionic conductivity retention after prolonged aging in 2 M NaOH solution at 80 °C for 1080 h. Fuel cell performance testing demonstrated a maximum power density of 532 mW cm −2 for the AEM QPBC-HPO with 100/200 mL min −1 of H 2 /O 2 flow and 100 % RH at 60 °C, while cell in-situ durability assessment at 100 mA cm −1 of constant current revealed a minimal voltage drop rate of only 0.12 mV h −1 after 72 h of operation, highlighting its promising potential in AEMFC.
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2024
·
IF 10.7
Jun Yang,Shuzhen Ma,Sihong Tao,Muci Wu,Qian Wu,Jingyi Wang
β-Galactosidase (lactase) plays a crucial role as a dietary supplement in managing lactose intolerance. Here, the catalytic activity of lactase was successfully activated for the first time through complexation with water-extractable β-glucans from highland barley (WHBG). Under simulated gastric/small intestinal digestive conditions, WHBG and lactase spontaneously formed complexes, resulting in a remarkable increase in catalytic activity up to 172.6 %. Structural analyses revealed that the incorporation of WHBG caused partial unfolding of lactase, thereby exposing its hydrophobic regions with active sites, and the electrostatic and hydrophobic interactions between the two played pivotal roles. Meanwhile, according to microstructure and particle size analyses, the dissociation of aggregates and the re-distribution of lactase molecules were also observed. Consequently, the enzyme-substrate contact was promoted, and the hydrolysis efficiency of complexed lactase in the digestion of lactose in milk was superior to that of native lactase. Notably, among WHBG30/50/70 obtained by continuous fractionation of WHBG with 30 %/50 %/70 % ethanol, WHBG70 exhibited the lowest molecular weights and size, and the highest negative ζ-potential, potentially contributing to its superior activation abilities on lactase. These findings challenge the traditional view of polysaccharides as enzyme inhibitors and highlight their potential for diverse applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2025
·
IF 4.7
Wanting Guo,Christian Marcus Pedersen,Zhihui Liu,Wenbo Dong,Lingyu Jia,Shuwei Chen,Yingxiong Wang,Yan Qiao
Carbazole (CAR) and anthracene (AN) are high value compounds derived from coal tar, but their separation is challenging due to their structural similarity. Promising results, using deep eutectic solvents (DESs) for the separation, have recently been obtained. However, choosing the optimal DESs for the separation of CAR and AN is difficult due to a lack of knowledge about the interaction of DESs with CAR and AN. Herein, the interactions between CAR and AN with seven DESs containing ethylene glycol (EG) as the hydrogen bond donor (HBD) were investigated by nuclear magnetic resonance (NMR). The interaction between CAR and tetrabutylammonium chloride/ ethylene glycol (TBAC/EG) was investigated using various NMR methods such as chemical shift titration, variable temperature NMR (VT-NMR), relaxation time measurements and diffusion-ordered spectroscopy (DOSY). From the chemical shift differences of the N H proton of CAR, a strong interaction between CAR and the DES consisting of TBAC and EG, was revealed. TBAC/EG was therefore proposed as a promising solvent for the separation of CAR and AN. In addition, VT-NMR showed that the hydrogen bonding interaction between CAR and TBAC/EG increased with decreasing temperature. The changes in relaxation time (T 1 , T 2 ), molecular correlation time (τ c ) and the molecular self-diffusion coefficients (D) supported the existence of interactions between CAR and TBAC/EG, presumably dominated by hydrogen bonding between the N H and the chloride ion. This study introduces an efficient method for screening solvents to separating CAR and AN, and it can also be applied to other fields of separating complex mixtures.
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Haohan Song,Junli Zhang,Xiao Wang,Yanmei Zhou,Chenggong Xu,Xiaobin Pang,Xiaojun Peng
Carbazole-based fluorescent probes have a significant edge on structure and optical properties, but stokes shift of them were mostly less than 100 nm. In this work, a novel carbazole-based fluorescent probe, which featured with a large stokes shift (128 nm), was used to effectively detect homocysteine (Hcy) and cysteine (Cys). This probe revealed obvious color variation and a “turn-on” alteration of fluoresence toward Hcy and Cys. Furthermore, the probe works under physiological conditions and can image thiol in living cells as well as zebrafish because of its wonderful cell permeability. Notably, it provides a possibility to detect endogenous bio-thiols quantitatively in living cells.
✓ 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）