CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·Vol. 41
·期 8
·1305-1316
·
IF 4.3
Chen Hao,Chu Fang-Yuan,Zhuang Hai-Yan,Wang Lu,Ye Zhi-Min,Dong Wei,Xie Zhi-Peng,Xie A.-Ming
Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave absorption. To solve this problem, a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous polymer. The topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique, and the controlled growth of polypyrrole in the channel constructs a unique network structure. The balance of excellent composite backbone structure, proper conductivity, attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption performance. As a result, with low filler loading of 10 wt%, a strongest reflection loss of −52.68 dB and a maximum effective bandwidth of 5.76 GHz. Additionally, CST simulations of the radar scattering cross section have been carried out to verify the excellent material properties. This study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.
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CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·Vol. 41
·期 11
·1695-1705
·
IF 4.3
Xie Yan-Kun,Feng Lu-Kun,Li Dong-Dong,Tang Yin,Zhu Cai-Zhen,Wang Ming-Liang,Xu Jian
Quasi solid-state succinonitrile (SN)-based polymer electrolytes have emerged for lithium-metal batteries due to their excellent ion-conductivity at room temperature, wide electrochemical stability window (ESW, usually >5 V). However, the practical application of these solid SN-based polymer electrolytes is hampered by the flammability and the inherent instability of SN to Li-metal anode. In this work, solid SN-based polymer electrolytes were prepared with succinonitrile, ethoxylated trimethylolpropane triacrylate (ETPTA), triethyl phosphate (TEP) and fluoroethylene carbonate for Li-metal battery via in situ polymerization method. The SN-based polymer electrolytes with 5 wt% triethyl phosphate and FEC showed good nonflammability, superior ion-conductivity as high as 1.01×10 −3 S/cm, and wide ESW of 5.41 V. This SN-based polymer electrolyte also exhibited excellent interfacial compatibility to lithium metal anode. And it also delivered a high specific capacity of 156 mAh/g at 0.2 C at ambient temperature, and presented stable cycling at 1.0 C with a specific capacity retention of 98.4% after 1000 cycles. This work provides an alternative and simple strategy to realize the practical application of the solid-state SN-based polymer electrolyte.
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Chinese Journal of Integrative Medicine
·
2023
·
IF 2.9
Qian Xiao-li,Meng Di,Liu Heng,Liu Chao-he,Zhou Ping,Yang Yin-he,Wang Jia-peng,Xiao Huai,Ding Zhong-tao
Objective To explore the proliferation inhibitory effect of quinones from Blaps rynchopetera defense secretion on colorectal tumor cell lines. Methods Human colorectal cancer cell HT-29, human colorectal adenocarcinoma cell Caco-2 and normal human colon epithelial cell CCD841 were chosen for the evaluation of inhibitory activity of the main quinones of B. rynchopetera defense secretion, including methyl p-benzoquinone (MBQ), ethyl p-benzoquinone (EBQ), and methyl hydroquinone (MHQ), through methyl thiazolyl tetrazolium assay. The tumor-related factors, cell cycles, related gene expressions and protein levels were detected by enzyme-linked immunosorbent assy, flow cytometry, RT-polymerase chain reaction and Western blot, respectively. Results MBQ, EBQ, and MHQ could significantly inhibit the proliferation of Caco-2, with half maximal inhibitory concentration (IC 50 ) values of 7.04 ± 0.88, 10.92 ± 0.32, 9.35 ± 0.83, HT-29, with IC 50 values of 14.90 ± 2.71, 20.50 ± 6.37, 13.90 ± 1.30, and CCD841, with IC 50 values of 11.40 ± 0.68, 7.02 ± 0.44 and 7.83 ± 0.05 µg/mL, respectively. Tested quinones can reduce the expression of tumor-related factors tumor necrosis factor α, interleukin (IL)-10, and IL-6 in HT-29 cells, selectively promote apoptosis, and regulate the cell cycle which can reduce the proportion of cells in the G 1 phase and increase the proportion of the S phase. Meanwhile, tested quinones could up-regulate mRNA and protein expression of GSK-3β and APC, while down-regulate that of β-catenin, Frizzled1, c-Myc, and CyclinD1 in the Wnt/β-catenin pathway of HT-29 cells. Conclusion Quinones from B. rynchopetera defense secretion could inhibit the proliferation of colorectal tumor cells and reduce the expression of related factors, which would be functioned by regulating cell cycle, selectively promoting apoptosis, and affecting Wnt/β-catenin pathway-related mRNA and protein expressions.
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Nano Research
·
2023
·Vol. 16
·期 5
·6290-6297
·
IF 9.9
Cai Jiahao,Song Shizheng,Zhu Lijie,Lu Qipeng,Lu Zong,Wei Yanying,Wang Haihui
A kind of two-dimensional (2D) metal-organic framework (MOF) material, Cu-meso-tetrakis (4-carboxyphenyl) porphine (Cu-TCPP) nanosheets with wrinkled and flat morphologies are used as building blocks to assemble membranes by vacuum filtration (VF) and electrophoretic deposition (EPD) as energy-efficient nanofiltration (NF) membranes to remove dyes from water. Since the nanosheets with wrinkled structure can provide additional water transport channels, thereby increasing the water permeance, in the premise of a high rejection (> 97.0%) for the dye brilliant blue G (BBG) (1.60 nm × 1.90 nm), the water permeance of the membrane assembled by the wrinkled nanosheets (∼ 1170 nm) is about 4 times that of the membrane assembled by the flat nanosheets (∼ 530 nm), reaching 16.39 L·m −2 ·h −1 ·bar −1 . Additionally, the use of the relatively flat nanosheets and the membrane preparation method of electrophoretic deposition is more conducive to stack nanosheets orderly and reduce defects. Therefore, the water permeance of the membrane prepared by EPD (∼ 1170 nm) with flat nanosheets is about twice that of the membrane prepared by VF (∼ 530 nm), achieving 9.40 L·m −2 ·h −1 ·bar −1 with similar rejection (> 97.0%) of dye evans blue (EB) (3.10 nm × 1.20 nm). Furthermore, these membranes still exhibit good separation performance at high pressure of 0.6 MPa. Nanosheets with diverse structures and various membrane fabrication processes provide new directions for the separation performance optimization of 2D MOF materials for water purification.
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JOURNAL OF SOILS AND SEDIMENTS
·
2023
·Vol. 23
·期 6
·2473-2481
·
IF 3.6
Li Ke-wei,Lu Hai-long,Nkoh Nkoh Jackson,Xu Ren-kou
Purpose Phyllosilicate minerals are the important components in soils and an important source of activated aluminum (Al) during soil acidification. However, the mechanisms for Al activation in phyllosilicate minerals were not understood well. This study was designed to investigate the role of hydroxyl groups on the surface of montmorillonite in acidification-induced activation of solid aluminum. Materials and methods Montmorillonite was treated at high temperatures to remove the hydroxyl groups from its surface, and then XRD, FTIR, and 27 Al NMR of montmorillonite before and after high-temperature treatment were determined. After that, Al activation during acidification of montmorillonite treated at different temperatures was investigated using the constant pH titration method. Results and discussion The results showed that hydroxyl groups on the surface of montmorillonite can effectively be removed when the temperature was raised to 670 °C. After high-temperature treatment, the crystallinity of the montmorillonite was reduced. The montmorillonite layer space was reduced, the pH and cation exchange capacity (CEC) of the mineral were decreased, and consequently the amount of acid consumed during acidification was significantly reduced. The decrease of CEC and surface hydroxyl groups in the mineral was responsible for the reduction in acid consumption during mineral acidification. After high-temperature treatment, the Al coordination structure of montmorillonite was transformed from six-coordination to four-coordination. The removal of surface hydroxyl groups inhibited the activation of Al during montmorillonite acidification, and the inhibition effect was increased with increasing temperatures below the complete dehydroxylation point. Conclusions The activation of Al during montmorillonite acidification was inhibited, suggesting that the hydroxyl groups at the edge of montmorillonite played an important role in Al activation process.
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JOURNAL OF ELECTROCERAMICS
·
2023
·Vol. 50
·期 4
·97-111
·
IF 1.7
Luan Saiwei,Wang Pengfei,Zhang Lei,He Yanmei,Huang Xiong,Jian Gang,Liu Cuicui,Yu Shuhui,Sun Rong,Cao Xiuhua,Fu Zhenxiao
Ultrafine ceramic powders with high tetragonality are the fundamental for the multi-layer ceramic capacitors (MLCCs). In this study, an efficient method of atmospherically hydrothermal assisted solid-state synthesis for ultrafine BaTiO 3 particles is presented. The BaTiO 3 nanopowders with homogeneous distribution, a mean particle size ~ 260 nm and high tetragonality of 1.0095 were obtained by at the optimal parameters of hydrothermal time of 6 h, Ba(OH) 2 ·8H 2 O/BaCO 3 = 0.25/0.75 and calcination temperature of 1000 o C. XRD and HRTEM analyses revealed a “core-shell” structure of TiO 2 @BaTiO 3 formed in the first-step hydrothermal process, which reduces the diffusion distance between BaCO 3 and TiO 2 , resulting in a lower calcination temperature at the second-step solid-state reaction. Compared with pure hydrothermal and solid-state reaction processes, the atmospherically hydrothermal assisted solid-state synthesis in this study shows larger ability for improving the particle size distribution and the tetragonality, reducing defects of BaTiO 3 particles. In particular, the grain size, sintering density, and dielectric constant at the Curie temperature of BaTiO 3 ceramics are 1.93 μm, 98%, and 7066, respectively. In the solid-state reaction stage, the lattice diffusion distance from BaO to TiO 2 tends to decrease due to the formation of BaTiO 3 shells, thus, high tetragonal and relatively small particle size of BaTiO 3 powder was synthesized. This work presents a method for preparing ultrafine BaTiO 3 powders with large tetragonality for MLCCs.
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POLYMER BULLETIN
·
2023
·
IF 3.2
Xiong Ao,Li Junqian
Fabrication of waterproof decorative paintings has attracted a great deal of interest. In this work, in situ reaction using poly(glycidyl methacrylate) (PGMA) and polyhedral oligomeric silsesquioxane with amino group at end (amino-POSS) was utilized to fabricate coatings at surfaces of papery/cloth decorative paintings via spray, which endowed the decorative paintings with excellent hydrophobicity, transparency, and weather ability. Firstly, ring opening of epoxy groups in PGMA, cross-linking structure in coatings, and strong coating/painting interface adhesion were achieved. Then, surface morphology of coatings was observed, and high surface roughness was confirmed. Next, high transparency and thermal stability of coatings were confirmed. Finally, surface water-contact-angles (WCAs) of coatings with various substrates were tested as a function of POSS content. Weathering resistances of coating surface on cloth substrate were studied. Coatings exhibit excellent properties such as high light transmittance (over 80%), high glass-transition temperature (upper limit ~ 113 ℃), high hydrophobicity (maximum WCA ~ 149°), and strong weathering resistances (the aged WCAs over 140°). Work innovation lies in simultaneously gained high hydrophobicity, good transparency, and strong weather ability. This work might pave a road for fabricating excellent coatings for protecting decorative paintings.
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Nature Communications
·
2023
·Vol. 14
·期 1
·1-9
·
IF 16.6
Ouyang Wenqi,Xu Xiayi,Lu Wanping,Zhao Ni,Han Fei,Chen Shih-Chi
There has been a compelling demand of fabricating high-resolution complex three-dimensional (3D) structures in nanotechnology. While two-photon lithography (TPL) largely satisfies the need since its introduction, its low writing speed and high cost make it impractical for many large-scale applications. We report a digital holography-based TPL platform that realizes parallel printing with up to 2000 individually programmable laser foci to fabricate complex 3D structures with 90 nm resolution. This effectively improves the fabrication rate to 2,000,000 voxels/sec. The promising result is enabled by the polymerization kinetics under a low-repetition-rate regenerative laser amplifier, where the smallest features are defined via a single laser pulse at 1 kHz. We have fabricated large-scale metastructures and optical devices of up to centimeter-scale to validate the predicted writing speed, resolution, and cost. The results confirm our method provides an effective solution for scaling up TPL for applications beyond laboratory prototyping.
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Nano Research
·
2023
·Vol. 16
·期 5
·6632-6641
·
IF 9.9
Zhang Zunjie,Liu Yang,Su Xiaozhi,Zhao Ziwei,Mo Zhenkun,Wang Chenyi,Zhao Yaling,Chen Ye,Gao Shuyan
Electrochemical nitrate reduction reaction (NO 3 RR) has great potential for ammonia (NH 3 ) synthesis benefiting from its environmental friendliness and sustainability. Cu-based alloys with elemental diversity and adsorption tunability are widely used as electrocatalyst to lower the reaction overpotential for NO 3 RR catalysis. However, phase separation commonly found in alloys leads to uneven distribution of elements, which limits the possibility of further optimizing the catalytic activity. Herein, an electro-triggered Joule heating method, possessing unique superiority of flash heating and cooling that lead to well-dispersed nanoparticles and uniform mixing of various elements, was adopted to synthesize a single-phase CuNi nano-alloy catalyst evenly dispersed on carbon fiber paper, CFP-Cu 1 Ni 1 , which exhibited a more positive NO 3 RR initial potential of 0.1 V versus reversible hydrogen electrode (vs. RHE) than that of pure copper nanoparticles at 10 mA·cm −2 in 0.5 mol·L −1 Na 2 SO 4 + 0.1 mol·L −1 KNO 3 solution. Importantly, CFP-Cu 1 Ni 1 presented high electrocatalytic activity with a Faradaic efficiency of 95.7% and NH 3 yield rate of 180.58 µmol·h −1 ·cm −2 (2550 µmol·h −1 ·mg
−1 cat
) at −0.22 V vs. RHE. Theoretical calculations showed that alloying Cu with Ni into single-phase caused an upshift of its d-band center, which promoted the adsorption of NO
− 3
and weakened the adsorption of NH 3 . Moreover, the competitive adsorption of hydrogen ions was restrained until −0.24 V. This work offers a rational design concept with clear guidance for rapid synthesis of uniformly dispersed single-phase nano-alloy catalyst for efficient electrochemical NO 3 RR toward ammonia.
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Food Analytical Methods
·
2023
·Vol. 16
·期 5
·909-917
·
IF 2.9
Xu Yanfen,Lu Ying,Yu Jianna,Liu Wen,Jing Guoxing,Li Wenshan,Liu Wenjie
Tuna is one of the most popular fish and therefore among the most commercially valuable seafood. However, inadequate refrigeration during the whole supply chain causes serious economic loss and food poisoning. One important result of tuna spoilage is the accumulation of biogenic amines such as histamine, which can be used as a sensitive indicator for Tuna freshness. Thus, the development of rapid, sensitive, and economic analytical methods for biogenic amines in Tuna is highly desired. This research developed a method that combines high-performance liquid chromatography (HPLC) and electrospray ionization ion mobility spectrometry (ESI-IMS) to detect 7 kinds of biogenic amines including tryptamine, tyramine, spermidine, cadaverine, β-phenylethylamine, putrescine, and histamine in tuna. The limit of detections (LODs) for 7 biogenic amines are 0.01, 0.02, 0.02, 0.17, 0.03, 0.04, and 0.15 mg L −1 respectively. The linear range of histamine and spermidine is 2–100 mg kg −1 , and the linear range of other biogenic amines is 0.5–10 mg L −1 . The recoveries of biogenic amines are between 69.39 and 112.65%. Compared to the traditional HPLC-based analytical method, the proposed method does not involve any derivatization steps, which greatly decreased the sample preparation time and cost. Another advantage of the developed method is the supplementary separation to the HPLC, in which coeluted biogenic amines can clearly be separated in the ion mobility dimension. The proposed method is applied to determining the concentration of biogenic amines in tuna storage, which showed that this method can quickly and accurately monitor the changes of biogenic amines in tuna during storage.
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ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2023
·Vol. 415
·期 10
·1889-1896
·
IF 4.3
Li Shuofan,Wu Jianxun,Zhang Weilai,Jiang Yue,Hu Miao,Chung Keng H.,Shi Quan
Thiophenes and sulfides are the dominant sulfur-containing compounds in petroleum and have been widely of concern in the fields of petroleum refining and geochemistry. In this study, a novel approach was developed for selective separation and characterization of petroleum-derived thiophenic and sulfide compounds. Thiophenic compounds were selectively converted to sulfonates in the presence of vitriolic acid and can be characterized by negative ion electrospray mass spectrometry. Thiophenic sulfonates were further separated from the oil by silica chromatography and enabled the molecular characterization of sulfides in the residual oil. Various model sulfur compounds and a vacuum gas oil were used to validate the method; thiophenic and sulfide biomarker compounds in a well-documented crude oil were selectively characterized. The results indicate that the approach is feasible for molecular characterization of thiophenic and sulfide compounds, which is complementary to recently developed methods for separation and/or ionization of sulfur compounds in petroleum. Graphical Abstract
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Journal of Biological Engineering
·
2023
·Vol. 17
·期 1
·1-14
·
IF 5.6
Yuan Shan,Xu Chao,Jin Miaomiao,Xian Mo,Liu Wei
Background Aromatic primary amines (APAs) are key intermediates in the chemical industry with numerous applications. Efficient and mild biocatalytic synthesis is an excellent complement to traditional chemical synthesis. Our lab previously reported a whole-cell catalytic system for the synthesis of APAs catalyzed by carboxylic acid reductase from Neurospora crassa (ncCAR) and ω-transaminase from Ochrobactrum anthropi (OATA). However, the accumulation of toxic intermediates (aromatic aldehydes) during biocatalytic synthesis affected yields of APAs due to metabolic imbalance. Results In this work, the biocatalytic synthesis of APAs (taking cinnamylamine as an example) was metabolically regulated by the overexpression or knockout of five native global transcription factors (TFs), the overexpression of eight native resistance genes, and optimization of promoters. Transcriptome analysis showed that knockout of the TF arcA increased the fluxes of NADPH and ATP in E. coli , while the rate of pyruvate metabolism was accelerated. In addition, the genes related to stress and detoxification were upregulated with the overexpression of resistance gene marA , which reduced the NADPH level in E. coli . Then, the expression level of soluble OATA increased by promoter optimization. Overall, arcA and marA could regulate the catalytic rate of NADPH- dependent ncCAR, while arcA and optimized promoter could regulate the catalytic rate of OATA. Lastly, the cinnamylamine yield of the best metabolically engineered strain S020 was increased to 90% (9 mM, 1.2 g/L), and the accumulation of cinnamaldehyde was below 0.9 mM. This work reported the highest production of cinnamylamine by biocatalytic synthesis. Conclusion This regulatory process provides a common strategy for regulating the biocatalytic synthesis of other APAs. Being entirely biocatalytic, our one-pot procedure provides considerable advantages in terms of environmental and safety impacts over reported chemical methods.
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