SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
·
2020
·
IF 3.086
Zhe Ye,Zhenghao Zhu,Ning Ma,Xiaohua Wang,Dingxin Liu,Aijun Yang,Huan Yuan,Mingzhe Rong
The deterioration of transformer oil caused by particle contamination, especially copper particle, seriously affects the safe operation of oil-immersed transformers. Therefore, it is very important for the detection of metal particles in transformer oil. A new method based on laser-induced breakdown spectroscopy (LIBS) was first applied in the transformer oil diagnosis field. By screening out effective spots, the correlation between Cu particle concentration and LIBS signal was obtained after testing a set of oil samples with concentration range from 0.54 to 12.4 μg/g; the calibration curves of Cu I 324.75 nm /CN 358.6 nm and Cu I 327.39 nm /CN 358.6 nm were therefore established. The results shown high linearity, and the determination coefficient R 2 of the two calibration curves in range from 0.54 to 3.1 μg/g were superior to 0.99. The limit of detection (LOD) inferred from Cu I 324.75 nm /CN 358.6 nm fitting curve was 0.77 μg/g and met the critical value specified by industry standards. Due to its flexibility, it can be used as a new-type of particle concentration detection method for transformer oil.
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2020
·Vol. 26
·期 7
·3307-3314
·
IF 2.394
Zhu Yuhao,Han Yu,Wang Hui,Guo Qingpeng,Jiang Huize,Sun Weiwei,Xie Wei,Zheng Chunman,Xie Kai
Due to its high capacity and low density, lithium metal is considered as one of the most promising anodes for next-generation lithium batteries. However, the problems of dendrite and volume change are the main obstacles to limit its further development. Therefore, it is of great significance to realize the stable plating and stripping of lithium metal. The stability of lithium metal can be improved by compositing lithium with conductor materials, but the effect of conductor materials on lithium composite anode needs to be further studied. Herein, ionic or electronic conductor powders are introduced into the interior of lithium metal by hot-melt mixed coating method; Li/Cu, Li/Zn, and Li/Li 3 N composite anodes are prepared; and their electrochemical performances in solid and liquid batteries are studied. The results show that plating and stripping of lithium in composite anodes will take place preferentially around electronic or ionic conductor, rather than around lithium itself. For liquid batteries, the introduction of electronic conductor in lithium composite anode will make the electric field distribution more uniform and thus make the lithium deposition more stable, while the introduction of ionic conductor in composite anodes can improve the electrochemical stability of composite anodes in solid-state batteries. The capacity of the Li/Cu-LFP battery was 42.5 mAh g −1 after 500 cycles at 10 °C, corresponding to the 77% retention of its initial capacity.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 11
·5699-5708
·
IF 11.301
Xin Qian,Dongyang Wang,Yang Zhang,Haijun Wu,Stephen J. Pennycook,Lei Zheng,Pierre F. P. Poudeu,Li-Dong Zhao
The metallic elements with a small atomic radius can not only compensate for the intrinsic vacancies to improve the carrier mobility, but also can form interstitials to reduce lattice thermal conductivity. In this work, we investigate the contrasting roles of three different metallic elements with small atomic radius on the thermoelectric properties of n-type PbM0.01Se (M = Cu, Zn, Ni). We find that all the metallic elements can increase the carrier concentration as electron donors and improve the electrical transport properties. In addition, the lattice thermal conductivity of PbSe can be significantly decreased through the formation of interstitials by the incorporated extra metallic elements. We also find that the PbCu0.01Se sample exhibits a unique and complex behavior compared with the other samples due to the diffusion and the thermally activated oxidation of Cu+ ions. When the temperature increased to 673 K, the carrier concentration of PbCu0.01Se sample increases suddenly and continues to increase by nearly two folds, which we ascribe to the release of 3d orbital electrons in Cu+ ions. This results in a strong decoupling of the charge and heat transport in the material, which can be manifested by the overestimation of the electronic thermal conductivity when assuming strong electron–phonon coupling in Wiedemann–Franz law. A maximum ZT of ∼1.6 can be reached at 773 K and the average ZT of ∼0.96 can be achieved in PbCu0.01Se. Our results demonstrate the exceptional contrasting behavior of Cu in PbSe by comparing with Zn and Ni, and the thermoelectric performance of n-type PbSe can be enhanced through the introduction of extra metallic elements with small radius.
✓ 已验证
产品关联
DOI
高影响因子
Nano-Micro Letters
·
2020
·Vol. 12
·期 1
·1-13
·
IF 12.264
Pan Zhengbin,Han Ershuan,Zheng Jingui,Lu Jing,Wang Xiaolin,Yin Yanbin,Waterhouse Geoffrey I. N.,Wang Xiuguo,Li Peiqiang
Flower-like CeO 2 nanoparticles enhance the performance of CuO nanoparticle/Cu.
The system benefits from the heterojunction between p-type CuO and n-type CeO 2 .
The selective reduction of CO 2 to methanol on the target catalyst is studied.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Chenhuinan Wei,Xiao Zou,Qiming Liu,Shuxian Li,Chenxia Kang,Wei Xiang
CuS nanosheets modified Cu 2 O/CuO nanowire arrays (NWAs) were successfully fabricated on Cu foil by in-situ growth and successive ionic layer adsorption and reaction (SILAR) methods without binders. The three-dimensional Cu 2 O/CuO NWAs not only showed strong binding force with current collector but also provided abundant surface area to support CuS nanosheets. Different morphologies of CuS were obtained by varying the Cu(NO 3 ) 2 and Na 2 S concentrations and the SILAR cycle. When these step-wise prepared products were employed for non-enzymatic glucose sensing, the amperometric response of the optimized CuS/Cu 2 O/CuO/Cu electrode was approximately twice of that of Cu 2 O/CuO/Cu electrode. The result is attributed to the modification of CuS nanosheets with suitable amount which increases the active surface area of the electrode. This designed electrode presents an ultrahigh sensitivity of 4262 μA mM −1 cm −2 in the range from 0.002 to 4.096 mM, as well as the excellent selectivity, reproducibility and stability. Moreover, due to the facile preparation and the low cost of Cu based sensors, the CuS/Cu 2 O/CuO/Cu electrode will be one kind of promising materials for constructing practical non-enzymatic glucose sensors.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 27
·9337-9344
·
IF 7.059
Aili Wang,Lili Zhao,Hui Liu,Ziqian Zhou,Chengbo Li,Yong Xiang,Weijia Zhou,Feng Hao
The development of low-dimensional non-precious metal catalysts for the hydrogen evolution reaction (HER) is highly desired for clean energy utilization. Herein, we have reported a facile synthesis protocol of Cu–Mo–O (CMO) nanowires and nanosheets on Cu foam (CMOW/CF and CMOS/CF) through a one-step reaction of Cu nanowires with (NH4)6Mo7O24 solution directly under mild conditions. The final product morphology has been tuned by mechanical stirring. The as-synthesized CMOS/CF exhibits a low operating overpotential of 112 mV at a current density of 10 mA cm−2 with a high electrochemical active area of 25.1 mF cm−2 and excellent long-term stability in the 1 M KOH electrolyte. Moreover, by using the CMOS/CF as cathodic and anodic electocatalysts, a two-electrode electrolyzer capable of driving 10 mA cm−2 at a cell voltage of 1.69 V was achieved, along with promising stability. The high performance of the CMOS/CF can be attributed to higher electrochemical area and more Mo catalytic sites induced by mechanical stirring. This work provides a facile method for the synthesis and catalytic site regulation through a simple method of low-dimensional nanomaterials for the HER with relatively high electrochemical active area and catalytic activity.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Faqiang Shi,Zhonghua Li,Limeng Liu,Jiandong Wu,Jinfu Ma,Yujin Wang
In previous works, it was found hard to synthesize “phase pure” ζ-Ta 4 C 3-z at relatively low temperatures even by prolonged heating, though ζ-Ta 4 C 3-z was believed stable till decomposition at ~2130°C. When the samples were subjected to TEM , vast richness of locally disordered structures in close relation with stacking of the close-pacted Ta-atom planes was observed. Although kinetic factors including diffusion of C atoms/vacancies and re-stacking of the Ta-atom planes explain the densely disordered structures, the richness of local disorders is a scenario that shows cohabitant of the cubic, rhombohedral, and hexagonal structures in a single grain, i.e. formation of a “hybrid grain” consisted of the three symmetries, indicating a transitional or intermediate stage before complete formation of the final phase of rhombohedral ζ-Ta 4 C 3-z . This time tantalum carbide ceramics TaC x with C:Ta atomic ratios x = 0.66 and 0.7 were prepared by reaction hot pressing of TaC and Ta powder mixtures. 5–30 mol% Cu/Ag additives and heat treatments were used to reproduce “hybrid grains” to facilitate further TEM and HRTEM observations on the disordered hybrid grains to argue for the transitional/intermediate stage. The cohabitant cubic, rhombohedral, and hexagonal structures in single grains may also help explain the difficulty in identification of the various phases by XRD in the transitional/intermediate stage of ζ-Ta 4 C 3-z reaction. Microstructural evolution and fracture toughness of the composites were also investigated.
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2019
·
IF 5.667
Yangyang Yan,Chen Gao,Jianjun Li,Tao Zhang,Guang Yang,Zhongkai Wang,Zan Hua
Herein we report the synthesis of a cellulose-grafted bottlebrush copolymer with nucleobases as hydrophobic moieties. Well-defined spherical micelles from this bottlebrush copolymer were fabricated via a solvent switch method. A morphological transition from spheres to worms was only observed to occur when a diblock copolymer with a complementary nucleobase functionality was introduced. Hydrophobic interaction is not capable of triggering the morphological transformation, and the diblock copolymer with the heterogeneous acrylamide nucleobase monomer can induce the morphological transition at higher A:T molar ratios, which might be caused by the weak H-bonding interaction. This supramolecular “grafting to” method enables the preparation of a series of nanoparticles with similar shapes and dimensions but distinct surface properties such as zeta potentials. Moreover, reversible morphological transitions between worm-like micelles and spheres can be achieved using a reversible collapsing and swelling of a thermoresponsive polymer. This work highlights that a supramolecular “grafting to” approach between complementary nucleobases can be utilized to tune morphologies and surface properties of nanoparticles.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2019
·
IF 2.584
Wei Sun,Qi Sun,Qiang Zhao,Luminita Marin,Xinjian Cheng
In this work, SiO2 microspheres were first prepared by a conventional Stöber method and then etched by NaOH solution to obtain porous ones. By tuning the degree of etching, specific surface area of SiO2 microspheres could be controlled. Then, small fluorescent molecules are synthesized and incorporated onto the surface and/or pores of the SiO2 via layer-by-layer reaction to obtain fluorescent microspheres, namely, SiO2–NH2–BODIPY (SiNBB), SiO2–NH2–BODIPY–indole–benzothiazole (SiNBIT), and SiO2–NH2–BODIPY–indole–benzoxazole (SiNBIO). The as-prepared microspheres SiNBB exhibit highly sensitive and selective recognition ability for Hg2+ and Pb2+. When SiNBB encounters Hg2+ and Pb2+, the fluorescence intensity of SiNBB is increased up to fivefold. SiNBIT and SiNBIO are solely sensitive to Hg2+, and both have a single high sensitivity to recognize Hg2+. The adsorption efficiency of Hg2+ by the three fluorescent microspheres SiNBB, SiNBIT, and SiNBIO reached 2.91, 0.99, and 0.98 g/g of microspheres, respectively. Experimental results of A549 cells and zebrafish indicate that the fluorescent microspheres are permeable to cell membranes and organisms. The distribution of Hg2+ in the brain of zebrafish was obtained by the fluorescence confocal imaging technique, and Hg2+ was successfully detected in A549 cells and zebrafish.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Faqing Shi,Limeng Liu,Yujin Wang,Guihong Geng
TaC 0.6 -Cu composites were fabricated by hot pressing of TaC, Ta and Cu powder mixtures. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, scanning-transmission microscopy, X-ray energy-dispersive spectroscopy, and selected area electron diffraction were used to investigate formation process and growth behavior of the ζ-Ta 4 C 3-x lamellae. Cu addition did not change the reaction sequence of TaC + Ta → Ta 2 C + TaC y → ζ-Ta 4 C 3-x to form the targeted ζ-Ta 4 C 3-x phase, but enhanced growth of ζ-Ta 4 C 3-x lamellae by introducing a dissolution-reprecipitation mechanism due to presence of Cu liquid at high temperatures. ζ-Ta 4 C 3-x could directly nucleate and grow on h-Ta 2 C grain surface, meanwhile C immediately reacted with Ta solutes in Cu liquid after the C atoms diffusing along the {111} TaCy stacking faults out of parental γ-TaC y grains to initiate extension of ζ-Ta 4 C 3-x lamella outside the γ-TaC y grains, thus grew large ζ-Ta 4 C 3-x lamellae with a uniform thickness in the microstructure of the TaC 0.6 -Cu composites. The TaC 0.6 -Cu composites with large ζ-Ta 4 C 3-x lamellae in the microstructures showed increase in fracture toughness.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 72
·42533-42542
·
IF 3.049
Junyan Tang,Xiaoya Liu,Chengwei Yang,Zhening Zhang,Rui Sun,Hongmei Li,Caolong Li,Fei Wang
Poly(1,3,5-triethynylbenzene) (PTEB), a newly developed conjugated arylacetylene polymer, was utilized for photoelectrochemical (PEC) enzymatic bioanalysis in this work. The porous nanofiber framework of PTEB film which produced an apparent cathodic photocurrent under visible light illumination was fabricated on an indium tin oxide (ITO) electrode via copper-surface mediated interface Glaser polycondensation. As the photocurrent density of the metal-free photocathode displayed a characteristic O2 dependency, the consumption of dissolved oxygen caused by the modified glucose oxidase (GOx) in biocatalysis induced a depressed photoresponse in the presence of glucose. The fabricated PEC transducer exhibited favorable glucose sensing performances in the linear range of 5 μM to 8 mM and with the detection limit of 1.7 μM; it could also be employed in glucose monitoring in human serum. Moreover, the acetylenic carbon-rich polymer possessed the superior features of being cost-effective in preparation and machinable in device development, which sheds light on the exploration of an advanced PEC sensing platform based on conjugated organic polymers for the bioanalysis of valuable analytes.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Packaging and Shelf Life
·
2019
·
IF 3.63
Zi-Wei Jiang,Wen-Wen Yu,Yan Li,Lei Zhu,Chang-Ying Hu
Nanocopper with different concentrations was introduced to homopolymer polypropylene (PP-H) matrix to prepare nanocopper/PP-H composite film. Film appearance, mechanical and thermal properties were investigated. Migration test to 3% acetic acid (w/v) food simulant, film antibacterial ability and human hepatotoxicity were conducted to further evaluate film safeness. FTIR results suggest that nanocopper particles were physically dispersed in PP-H matrix and the addition of nanocopper could significantly improve thermal and mechanical properties of composite films, ensuring its potential utilization for food packaging. Also, the composite film showed great antibacterial ability including Escherichia coli , Staphylococcus aureus , Shigella castellani and Bacillus subtilis . At 70 ℃, when the initial concentration of added nanocopper reached 1% (w/w) or higher, the concentration of copper migrated from film to acetic food simulant would reach to 4.5 μg/g and would start damaging L-02 cells. This study provides important information for the potential utilization of nanocopper in food packaging films.
✓ 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）