CATALYSIS LETTERS
·
2020
·Vol. 151
·期 3
·734-747
·
IF 2.482
Zhang Xiaorui,Chen Chen,Jiang Caiyun,Zhou Haifei,Cao Wang,Wang Yuping
Abstract A new type of Ag 3 PO 4 /UiO-66-NH 2 Z-scheme heterojunction nanocomposite with visible light catalytic activity was successfully prepared. The synthesis of the composite was confirmed by XRD, FT-IR, SEM, TEM, EDS, XPS. The Ag 3 PO 4 /UiO-66-NH 2 Z-scheme heterojunction can effectively improve the utilization of visible light. The optimal Ag/U/1/4 composite has the highest degradation efficiency for methylene blue (MB, 30 mg/L) in 90 min (80%) and Norfloxacin (NOR, 10 mg/L) in 150 min (85%). The decrease of Nyquist radius and the enhancement of photocurrent response indicated that the combination of photogenerated electron–hole pair in Ag 3 PO 4 /UiO-66-NH 2 composite material is significantly inhibited. N 2 adsorption–desorption and zeta potential results indicated that biggish specific surface area and negative zeta potential value are more favorable for the adsorption of the cationic dye MB. The cyclic test verified the good stability of Ag 3 PO 4 /UiO-66-NH 2 heterojunction material. Furthermore, the photocatalytic degradation mechanism of MB was discussed by introducing different traps to inhibit the possible active substances in the degradation process. This work testified that an efficient photocatalytic composite based on metal–organic frameworks can be used for the degradation of pollutants. Graphic Abstract
✓ 已验证
产品关联
DOI
高影响因子
Nature Protocols
·
2020
·Vol. 16
·期 1
·431-457
·
IF 10.419
Jin Shuai,Gao Qiang,Gao Caixia
Base editors can achieve targeted genomic base conversion. However, the off-target issue is one of the major concerns in their application. Whole-genome sequencing (WGS) at the individual level can provide direct information on genome-wide specificity, but it is difficult to distinguish true off-target single-nucleotide variants (SNVs) induced by base editors from background variation. Here we describe an unbiased WGS method for evaluating the specificity of base editors in rice. In this protocol, we describe the experimental design and provide details of vector construction, rice transformation and tissue culture, as well as a comprehensive WGS data analysis pipeline for overcoming two related core problems in various plant species: high background mutation rates and the heterogeneity of examined populations. Using this protocol, researchers can straightforwardly and accurately assess the genome-wide specificity of base editors and other genome editing tools in 12–15 weeks.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 28
·期 12
·15032-15042
·
IF 3.056
Zhao Zhilin,Xu Limei,Wang Yong,Li Bihan,Zhang Wenming,Li Xiaochen
Silver nanoparticles (Ag-NPs) are widely used in daily life and inevitably discharged into the aquatic environment, causing increasingly serious pollution. Research on the toxicity of Ag-NPs is still in infancy, little information is available on the relationships between oxidative stress and antioxidant, as well as damaging degrees of Ag-NPs to cellular structural components of Chlamydomonas reinhardtii ( C. reinhardtiii ). In the present study, we revealed the toxicity mechanism of C. reinhardtii under Ag-NPs stress using flow cytometry (FCM), metabolic methods, and transmission electron microscopy. The results showed that the chloroplasts were damaged and the synthesis of photosynthetic pigments was inhibited under Ag-NPs stress, which inhibited the growth of C. reinhardtii . Meanwhile, Ag-NPs also caused C. reinhardtii to produce excessive reactive oxygen species (ROS), increased malondialdehyde content and changed the permeability of cell membrane, resulting in the acceleration of internalization of Ag-NPs. The decrease of cell size and intracellular chlorophyll autofluorescence was observed with FCM. To deal with the induced excessive ROS that could lead to lethal and irreversible structure damage, C. reinhardtii activated antioxidant enzymes including superoxide dismutase and peroxidase. This study provides new information for better understanding the potential toxicity risks of Ag-NPs in the aquatic environment.
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
·
2020
·Vol. 27
·期 12
·1400-1406
·
IF 1.213
Chen Yong-feng,Lv Xue-ming,Pang Zheng-de,Lv Xue-wei
The effect of the Al 2 O 3 content and basicity (the molar ratio of MgO to SiO 2 ) on the viscosity of a SiO 2 –MgO–FeO–Al 2 O 3 –CaO slag was studied to fully understand the smelting process of the ferronickel alloy. Experimental results show that the slag is a mixture of liquid and solid phases at the experimental temperature. The viscosity decreased as the basicity increased and increased as the Al 2 O 3 content increased. To determine the effect of the Al 2 O 3 content and basicity on the structure of the molten slag, Raman spectroscopy was performed on the slag sample, which was quenched from the high temperature with water. The Raman spectra showed that the fractions of the polymerization structural units decreased significantly as the basicity of the slag increased, resulting in a decrease in the apparent viscosity. However, Al 2 O 3 acts as a network former in the slag system, thereby making the slag structure further polymerized and increasing the viscosity.
✓ 已验证
产品关联
DOI
高影响因子
AAPS PHARMSCITECH
·
2020
·Vol. 21
·期 8
·1-11
·
IF 2.401
Su Yanping,Lu Wenxiang,Fu Xiaoling,Xu Ying,Ye Lixiang,Yang Jian,Huang Huihui,Yu Changxi
The aim of this study was to develop a suitable drug-in-adhesive patch for transdermal delivery of koumine. Acrylic polymer Duro-Tak® 87-4287, which contains hydroxyl groups, may significantly enhance the skin permeation of koumine from transdermal patches containing 0.93–3.72% koumine. Among permeation enhancers, 10% azone showed the greatest potential and increased the flux of koumine to 1.48-fold that of the control. Therefore, an optimized patch formulation containing 3.72% koumine and 10% azone in Duro-Tak® 87-4287 that offers good physical properties was selected for an in vivo pharmacokinetic study using rats. The maximal plasma drug concentration ( C max ) of koumine after transdermal administration (4 mg/patch) was 25.80 ± 1.51 ng/mL, which was in the range of those after oral administration (3 mg/kg and 15 mg/kg). The time to the maximal concentration ( T max ) and the half-life ( t 1/2 ) of the drug with transdermal administration were 3.96 ± 0.46 h and 21.10 ± 1.36 h, respectively, which were longer than those with oral administration. Furthermore, the area under the concentration-time curve (AUC 0–72 h ) of 898.20 ± 45.57 ng·h/mL for the transdermal patch was much higher than that for oral administration (15 mg/kg). In conclusion, the drug-in-adhesive patch containing koumine provides a steady plasma koumine level and sustained release in vivo and can be an effective means of transdermal delivery for koumine.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 16
·9243-9256
·
IF 4.21
Huang Zhonglei,Liu Chao,Feng Xiaoyan,Wu Meiyan,Tang Yanjun,Li Bin
Abstract Dissolution and regeneration of cellulose is of vital importance for its end use. In the present work, the effect of different regeneration solvents (i.e. water, ethanol, and N, N-dimethylacetamide (DMAc)) on the characteristics of the regenerated cellulose from lithium bromide trihydrate (LBTH) molten salt was comprehensively investigated. It was found that the regenerated celluloses displayed obvious changes in macro- and micro-morphologies compared with the original microcrystalline cellulose (MCC). Furthermore, after the dissolution and regeneration process, the crystalline structure of cellulose was changed from cellulose I to cellulose II or amorphous structure, and the crystallinity of cellulose clearly decreased due to the deconstruction and rearrangement of cellulose chains. Moreover, the regenerated cellulose with ethanol had a relatively higher degree of crystallinity (70.2%) than that with water (42.3%) and DMAc (33.2%). Both X-ray Diffraction (XRD) and Attenuated Total Reflection Flourier transformed Infrared Spectroscopy (ATR-FTIR) analysis results indicated that ethanol as a regeneration solvent could be more beneficial to rearrange cellulose molecular chains and rebuild a more ordered structure compared to water and DMAc. In addition, thermogravimetric analysis showed that regenerated cellulose from LBTH exhibited a lower decomposition onset temperature and a higher char yield (over 17.8%) compared with the raw MCC (2.8%). The obtained results verified that regeneration solvents could substantially affect the reconstitution of cellulose molecule chains during regeneration as well as the multiscale structures and properties of the regenerated cellulose. Graphic abstract
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2020
·Vol. 96
·期 3
·753-762
·
IF 2.008
Zhu Rui,Bi Zun,Jia Ke,Liu Yunfei,Lyu Yinong
A series of single-component ScF 3 :Dy 3+ , Eu 3+ , Ce 3+ phosphors prepared by means of microwave hydrothermal method were explored for light-emitting diodes. The as-prepared samples were characterized via X-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence (PL) spectroscopy. In order to rationalize the experimental results, first-principle calculations based on density functional theory had been carried out to discover electronic structures. PL performance of the RE 3+ -doped phosphors exhibited well-defined bands in the visible region. By adjusting the ratios of Ce/Dy/Eu, the color of the as-prepared phosphors can vary from blue (0.24, 0.23) to red (0.51, 0.30) across the white (0.34, 0.26) region according to the chromaticity coordinates. The results suggested that the Dy/Eu/Ce-doped ScF 3 might act as down-convert phosphors for near ultraviolet light-emitting diodes, especially for white LEDs. What is more, it can also promote a deep comperhension of the relationship between structure and properties in ScF 3 -based phosphors.
ScF 3 :RE 3+ phosphors with alterable bandgaps can emit light from blue to orange–red across white under the excitation of near ultraviolet light. Introduction of rare earth ions induced the variation of energy band structures in ScF 3 -based phosphors because of the existence of f , p , and d orbits in RE 3+ , therein f and p orbits of RE 3+ made the band structure downwards, the p hybridizing with Sc-3 d promoted the band toward high-energy region.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 34
·16158-16170
·
IF 3.553
Li Menglin,Sheng Lei,Zhang Hui,Yang Yang,Xu Rong,Bai Yaozong,Song Shangjun,Liu Gaojun,Wang Tao,Huang Xianli,He Jianping
Abstract In order to solve the shortcomings of the current traditional commercial polyolefin microporous membranes with worse thermostability at high temperature, polyimide (PI) nanofiber membranes prepared by electrospinning are promising separators for lithium ion batteries that operate at high temperatures. This preparation includes the forming process of poly(amic acid) (PAA) fibers membrane and thermal-imidization process. In this study, we design the experiment of thermal-imidization for PAA fibers to improve the mechanical strength and the electrochemical performance of the obtained PI nanofiber membrane. It is found that the degradation phenomenon and the crosslinking function occur after the imidization during the heat treatment. The mechanical strength of PI nanofiber membrane gets improved with new crosslinking system after being heat-treated at 350 °C. LiCoO 2 /Li cells based on such PI nanofiber membranes exhibit excellent cycle performance (300 cycles) and rate performance (even at high rates of 6 C), better than those employing polyolefin microporous membranes. Graphic abstract During the heat treatment of polyamic acid, a thermal imidization process will occur. At the same time, different heat treatment temperatures will lead to differences in the degree of imidization and the structure of the fiber membrane material. It is important to understand the thermal imidization process. The effect of thermal imidization temperature on the performance of the electrospun polyimide lithium ion battery separator is studied. The experimental results show that although the degree of imidization is decreased by the heat treatment at 350 °C, it has better cycle performance (300 circles) and rate performance (even at high rates of 6 C).
✓ 已验证
产品关联
DOI
高影响因子
APPLIED COMPOSITE MATERIALS
·
2021
·Vol. 28
·期 1
·219-233
·
IF 2.181
Wang Pei,Deng Guanyu,Zhu Hongtao,Yin Jian,Xiong Xiang,Zhang Hongbo
To improve electrical conductivity of the carbon-based pantograph strip, a sliding contact material of pyrolytic carbon (PyC) coated-copper foam/carbon composite was fabricated by chemical vapor deposition technology, followed by densifying processes of furan resin impregnation and carbonization. Morphology, electrical conductivity, wear and friction behavior of the composites are investigated to clarify the effect of PyC thickness (from 0 μm to 280 μm) on tribological behaviors and current transfer characteristic. The results show that there is a good interface combination between copper foam and resin carbon matrix in the composites after the improvement of interface wettability by inserting PyC layer. The composite has great advantages in electrical conductivity and density due to the copper foam and PyC layer with three-dimensional structure. With increasing the PyC thickness, both electrical conductivity and wear resistance of the composite have steadily increasing tendency, but friction coefficient has no obvious change. In addition, an analytical model is developed to explore current transfer mechanisms of the PyC-copper foam/carbon composite, and the theoretical predictions are in agreement with the experimental observations, in term of electrical conductivity and porosity of composite preform.
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2021
·Vol. 14
·期 8
·2846-2852
·
IF 8.897
Wang Dongdong,Al-Mamun Mohammad,Gong Wanbing,Lv Yang,Chen Chun,Lin Yue,Wang Guozhong,Zhang Haimin,Zhao Huijun
The cyclopentanone and derivatives are a class of crucial fine chemicals for various industries and currently produced by conventional petrochemical synthetic routes. Here, we demonstrated a new synthetic approach to directly fabricate N-doped carbon nanotube (N-CNTs) networks with confined Co nanoparticles from Co 2+ -impregnated bulk g-C 3 N 4 as high performance hydrogenation rearrangement (HR) catalyst to efficiently convert a wide spectrum of biomass-derived furanic aldehydes to the corresponding cyclopentanones in water under a record-low H 2 pressure of 0.5 MPa and mild temperature. We unveiled a Co-catalysed bulk g-C 3 N 4 decomposition/carbonisation CNTs formation mechanism. A new HR pathway was also unveiled.
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-7
·
IF 12.121
Tian Jinshu,Tan Jiangqiao,Zhang Zhaoxia,Han Peijie,Yin Min,Wan Shaolong,Lin Jingdong,Wang Shuai,Wang Yong
Direct oxidation of methane to value-added C 1 chemicals (e.g. HCHO and CO) provides a promising way to utilize natural gas sources under relatively mild conditions. Such conversions remain, however, a key selectivity challenge, resulting from the facile formation of undesired fully-oxidized CO 2 . Here we show that B 2 O 3 -based catalysts are selective in the direct conversion of methane to HCHO and CO (~94% selectivity with a HCHO/CO ratio of ~1 at 6% conversion) and highly stable (over 100 hour time-on-stream operation) conducted in a fixed-bed reactor (550 °C, 100 kPa, space velocity 4650 mL g cat −1 h −1 ). Combined catalyst characterization, kinetic studies, and isotopic labeling experiments unveil that molecular O 2 bonded to tri-coordinated BO 3 centers on B 2 O 3 surfaces acts as a judicious oxidant for methane activation with mitigated CO 2 formation, even at high O 2 /CH 4 ratios of the feed. These findings shed light on the great potential of designing innovative catalytic processes for the direct conversion of alkanes to fuels/chemicals.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 11
·6704-6718
·
IF 4.22
Liu Xiao,Zhang Wenyi,Mao Linqiang,Yin Yong,Hu Linchao
Abstract FeOCl-MoS 2 was synthesized via calcination, which possessed excellent adsorption performance for methyl orange (MO). The characterization results showed that the FeOCl-MoS 2 was formed between MoS 2 and FeOCl phases, while a remarkable improvement in specific surface area and porosity was obtained in comparison with pure FeOCl and MoS 2 . The adsorption experiment results showed that the adsorption capacity of MO dye at 25 °C could reach 1615.11 mg/g. In addition, the pseudo-second-order kinetic model (R 2 > 0.99) has a good applicability to describe the adsorption of MO onto FeOCl-MoS 2 . Langmuir isotherm model (R 2 > 0.99) can describe the adsorption process well, proving that the adsorption is surface-controlled monolayer adsorption. Thermodynamic analyses showed the adsorption is an exothermic process and has spontaneity in nature. The adsorption of MO onto FeOCl-MoS 2 is attributed to electrostatic interaction. In particular, the adsorption capacity could still reach 82.1% of the initial adsorption capacity by alkali washing after five cycles. Hence, this study reveals that FeOCl-MoS 2 could be a high-efficient adsorbent for dyes removal from wastewaters. Graphical abstract
✓ 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）