Nano-Micro Letters
·
2021
·Vol. 13
·期 1
·1-15
·
IF 16.419
Wu Xinyu,Tu Tingxiang,Dai Yang,Tang Pingping,Zhang Yu,Deng Zhiming,Li Lulu,Zhang Hao-Bin,Yu Zhong-Zhen
Highlights
3D printing of MXene frames with tunable electromagnetic interference shielding efficiency is demonstrated.
Highly conductive MXene frames are reinforced by cross-linking with aluminum ions.
Electromagnetic wave is visualized by electromagnetic-thermochromic MXene patterns.
Abstract The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interference (EMI) shielding materials to assure the normal operation of their closely assembled components. However, the most current techniques are not adequate for the fabrication of shielding materials with programmable structure and controllable shielding efficiency. Herein, we demonstrate the direct ink writing of robust and highly conductive Ti 3 C 2 T x MXene frames with customizable structures by using MXene/AlOOH inks for tunable EMI shielding and electromagnetic wave-induced thermochromism applications. The as-printed frames are reinforced by immersing in AlCl 3 /HCl solution to remove the electrically insulating AlOOH nanoparticles, as well as cross-link the MXene sheets and fuse the filament interfaces with aluminum ions. After freeze-drying, the resultant robust and porous MXene frames exhibit tunable EMI shielding efficiencies in the range of 25–80 dB with the highest electrical conductivity of 5323 S m −1 . Furthermore, an electromagnetic wave-induced thermochromic MXene pattern is assembled by coating and curing with thermochromic polydimethylsiloxane on a printed MXene pattern, and its color can be changed from blue to red under the high-intensity electromagnetic irradiation. This work demonstrates a direct ink printing of customizable EMI frames and patterns for tuning EMI shielding efficiency and visualizing electromagnetic waves.
✓ 已验证
DOI
PubMed
高影响因子
Frontiers of Materials Science
·
2023
·Vol. 17
·期 3
·1-9
·
IF 2.7
Li Wenjing,Wu Ni,Che Sai,Sun Li,Liu Hongchen,Ma Guang,Wang Ye,Xu Chong,Li Yongfeng
Polyurethane (PU) foams are widely used in thermal management materials due to their good flexibility. However, their low thermal conductivity limits the efficiency. To address this issue, we developed a new method to produce tannic acid (TA)-modified graphene nanosheets (GTs)-encapsulated PU (PU@GT) foams using the soft template microstructure and a facile layer-by-layer (L-B-L) assembly method. The resulting PU@GT scaffolds have ordered and tightly stacked GTs layers that act as three-dimensional (3D) highly interconnected thermal networks. These networks are further infiltrated with polydimethylsiloxane (PDMS). The through-plane thermal conductivity of the polymer composite reaches 1.58 W·m −1 ·K −1 at a low filler loading of 7.9 wt.%, which is 1115% higher than that of the polymer matrix. Moreover, the mechanical property of the composite is ∼2 times higher than that of the polymer matrix while preserving good flexibility of the polymer matrix owing to the retention of the PU foam template and the construction of a stable 3D graphene network. This work presents a facile and scalable production approach to fabricate lightweight PU@GT/PDMS polymer composites with excellent thermal and mechanical performance, which implies a promising future in thermal management systems of electronic devices.
✓ 已验证
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2011
·Vol. 5
·期 4
·409-415
·
IF 0
Cao Hongfei,Feng Yakai,Wang Heyun,Zhang Li,Khan Musammir,Guo Jintang
By using the corresponding L -amino acid sodium as initiator, ɛ -caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions of ɛ -caprolactone (CL) with L -alanine and L -leucine, respectively, and p -dioxanone-depsipeptide (PDO-Leu) was prepared by the reaction of p -dioxanone (PDO) with L leucine. Two poly( ɛ -caprolactone) oligomers (PCL-Ala and PCL-Leu) of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of L -amino acid sodium and CL. The presence of the depsipeptide structure in these obtained products was confirmed by 1 H NMR spectra and the molecular weight of the poly( ɛ -caprolactone) oligomers was measured by gel permeation chromatography (GPC). These products contain a hydroxyl group and a carboxyl group in one molecule, which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers. By this way, the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.
✓ 已验证
DOI
Electrocatalysis
·
2022
·Vol. 14
·期 2
·247-258
·
IF 2.933
Zhao Zhipeng,Liu Yinmeng,Yi Wenjing,Wang Haiyang,Liu Zhongyi,Yang Jing-he,Zhang Meng
Binder-free nickel–cobalt phosphate (NiCoPO) micro flakes are evenly grown on the nickel foam (NF) by a simple hydrothermal method, which can act as a highly efficient bifunctional electrocatalyst (NiCoPO/NF) for both oxygen evolution reaction (OER) and urea oxidation reaction (UOR). NiCoPO/NF presents the relatively prominent OER and UOR activities with ultralow potentials of 1.51 V and 1.34 V (vs. reversible hydrogen electrode) to reach the current density of 100 mA cm −2 , respectively. The outstanding UOR and OER performance of NiCoPO/NF might be attributed to the fact that the successful incorporation of oxygen atoms into Ni/Co phosphate is beneficial for the oxidation of metal atoms at high overpotential. In addition, NF can improve the electrical conductivity to accelerate the electron transfer from the electrode to the catalyst. Additionally, in the alkaline solution (1 M KOH), NiCoPO/NF shows excellent durability and stability after the consecutive OER and UOR tests for 48 h. The design of NiCoPO/NF would pave the way to construct more efficient bifunctional electrodes for electrocatalytic water splitting with or without urea in alkaline solution, which provides a novel technological platform for the conversion of human waste into the sustainable energy. Graphical Abstract
✓ 已验证
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2018
·Vol. 315
·期 2
·119-126
·
IF 1.181
Tan Juan,Wang Yanfei,Liu Na,Liu Mouwu
The adsorption of uranium (VI) using tetraphenylimidodiphosphinate (Htpip) was studied. Factors of affecting sorption efficiency have been investigated and results showed the adsorption of uranium (VI) was equilibrium at pH 4.5, time 20 min, adsorbent dosage 0.005 g and initial concentration 50 mg L −1 reaching 99.86 mg g −1 of adsorption capacity and 99.86% of removal efficiency. Additionally, the interfering ions studies showed that the adsorbent possessed excellent adsorption selectivity of uranium (VI). The surface morphology of Htpip was investigated by SEM. The adsorption process of uranium (VI) onto Htpip fit the pseudo-second-order kinetic model and the Freundlich isotherm model very well.
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE
·
2012
·Vol. 23
·期 8
·1913-1919
·
IF 2.316
Li Ning,Yu Meihua,Deng Liandong,Yang Jun,Dong Anjie
Hydrogels with the advantages of prolonging drug release and administration convenience are necessary for intravaginal drug delivery to prevent sexual transmission of human immunodeficiency virus and other vaginal infections. In this study, the thermosensitive hydrogel of methylcellulose modified by stearic acid (MCS) were evaluated in the presence of NaCl and phosphates, which exhibited sol-to-gel transition performance at body temperature or even lower. The in vitro cytotoxicity and in vivo mucosal irritation were investigated and the results showed that MCS hydrogel possessed good biocompatibility similar with hydroxyethyl cellulose (HEC) gel. Significantly, the release studies revealed that MCS hydrogel could control tenofovir sustained release for 10 h without burst release, longer than that from HEC gel or poloxamer 407 hydrogel. Therefore, MCS thermosensitive hydrogel would be a promising carrier for intravaginal delivery of antiviral drugs for long time controlled release.
✓ 已验证
DOI
PubMed
高影响因子
Natural Products and Bioprospecting
·
2017
·Vol. 7
·期 6
·461-469
·
IF 0
Mahal Ahmed,Wu Ping,Jiang Zi-Hua,Wei Xiaoyi
Abstract Tetrahydrocurcumin (THC) is a major metabolite of curcumin and plays an important role in curcumin-induced biological effects. THC is a promising preventive and chemotherapeutic agent for cancer. A series of new pyrazole derivatives of THC have been synthesized as potent anticancer agents. Direct condensation of THC with various substituted hydrazines leads to new pyrazole derivatives of THC ( 1 – 18 ). The prepared compounds have been evaluated via in vitro MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay for their cell proliferation-inhibitory activity against human lung adenocarcinoma (A549), human cervical carcinoma (HeLa) and human breast carcinoma (MCF-7) cells. Most derivatives show significantly higher anticancer activity against all three tested cancer cell lines than the parent compound THC. Several compounds ( 7 , 8 , 12 , 13 and 15 ) display promising anticancer activity against MCF-7 cell line with IC 50 values ranging from 5.8 to 9.3 µM. The most active compound ( 8 ) is substituted with 4-bromophenyl group at the pyrazole ring and inhibits the growth of all three tested cancer cell lines with an IC 50 values of (8.0 µM, A549), (9.8 µM, HeLa) and (5.8 µM, MCF-7). The obtained compounds can be a good starting point for the development of new lead molecules in the fight against cancer. Graphical Abstract
✓ 已验证
DOI
PubMed
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2014
·Vol. 302
·期 1
·123-130
·
IF 1.415
Sun Zhi-Zhong,Wei Hong-Yuan,Wang Guan-Quan,Zhou Zhi-Jun,He Jia-Heng,Wang Jing,Luo Shun-Zhong
[ 131 I]-5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin and [ 131 I]-5-(4-aminophenyl)-10,15,20-triphenylporphyrin ( 131 I-TPPOH and 131 I-TPPNH 2 ) were prepared and their biodistribution properties were evaluated in normal Kunming (KM) mice and SMMC-7721 tumor-bearing BALB/c mice. The optimized labeling yields were 98 and 96 % for 131 I-TPPOH and 131 I-TPPNH 2 , respectively. They were stable in vitro saline and in vivo. Both compounds had a specific affinity to liver and lung, and mainly metabolized through liver. They showed a time-dependent accumulation and retainable characteristics in SMMC-7721 tumor. These results supported their potential value for targeted tumor therapy agents.
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2015
·Vol. 33
·期 11
·1618-1624
·
IF 1.835
Hu Wei,Cao Jing,Huang Yi-ling,Liang Sai
The anionic polymerization of N -vinylcarbazole (NVC) by using optically active anionic initiators such as the lithium salts of ( S )-1-(9H-fluoren-2-yl)-4-isopropyl-4,5-dihydrooxazole (( S )-1-FIDH) and ( S )-2-(9H-fluoren-2-yl)-4- isopropyl-4,5-dihydrooxazole (( S )-2-FIDH) and complexes of (-)-Sparteine with n -butylithium (n-BuLi-(-)-Sp) or fluorenyl lithium (FILi-(-)-Sp) was achieved. The yield and specific rotation of poly( N -vinylcarbazole)s (poly(NVC)s) were considerably affected by the molar ratio of ( S )-FIDH to NVC. The highest yield and specific rotation were obtained with Li- ( S )-1-FIDH as an initiator, with a molar ratio of monomer and initiator [M]/[I] = 10/1. The effects of the chiral initiators, type of solvent and the polymerization temperature were investigated. The obtained optical activity of polymers was attributed to asymmetric induction of the chiral initiators.
✓ 已验证
DOI
高影响因子
JOURNAL OF CLUSTER SCIENCE
·
2019
·Vol. 31
·期 2
·513-522
·
IF 2.125
Liu Qiang,Liu Yuqi,Zhang Qingqing,Wang Xinying,Li Wei
A new Pr(III)-based metal organic framework with formula {[Pr 2 (C 8 H 3 O 6 N)(SO 4 ) 2 ]·5H 2 O} n was hydrothermally synthesized and characterized by techniques of single crystal X-ray diffraction, infrared spectra (IR), thermogravimetric analysis (TGA), elemental analysis, powder X-ray diffraction (PXRD), and luminescent measurements. X-ray crystal structure analyses reveal that complex 1 is binuclear structure and all Pr(III) atoms show a coordination number of nine with a tricapped trigonal prismatic coordination geometry. Throughout the molecular structure, this lanthanide metal–organic frameworks exhibits a 3D architecture built by the 1D double-stranded chains of Pr ions linked by the 5-nitroisophthalic acid ligand and 2D Pr–SO 4 2− grid. In addition, the fluorescence, nitrogen adsorption properties and carbon dioxide adsorption properties of complex 1 were also investigated. The results indicate that the complex is not only a luminescent and mesoporous material, but also a potential material for selective absorption of carbon dioxide.
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 13
·8207-8218
·
IF 2.599
Zhang Bin,Zhu Han,Zou MeiLing,Liu XinRong,Yang Hui,Zhang Ming,Wu WeiWei,Yao JuMing,Du MingLiang
Small-sized and well-dispersed Pt–Au nanoparticles (Pt–AuNPs) grown on carbon nanofibers (Pt–AuNPs/CNFs) with excellent electroanalytical and electrocatalytic performance in the detection of H 2 O 2 and the catalytic hydrogen evolution reaction (HER) were designed and fabricated via electrospinning technology and an in situ thermal reduction process. Large numbers of Pt–AuNPs were homogenously distributed on the CNFs. A Pt–AuNP/CNF hybrid with low Pt content was utilized as a bifunctional electrocatalyst, exhibiting a higher response current of 116 μA without an enzyme in the detection of H 2 O 2 and a lower overpotential ( j = 10 mA cm −2 at −235 mV) and Tafel slope (84 mV decade −1 ) for HER than the PtNPs/CNFs and the AuNPs/CNFs. These results were ascribed to the specific nanostructure of the well-dispersed Pt–AuNPs, the favorable electron transport capability, the excellent durability of the CNFs, and the enhanced surface-specific area of the Pt–AuNPs/CNFs. This study offers a green and facile method for constructing a specific bimetallic nanostructure for application in catalytic fields.
✓ 已验证
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2023
·Vol. 17
·期 8
·1096-1108
·
IF 4.5
Hou De-Fa,Yuan Pan-Pan,Feng Zi-Wei,An Meng,Li Pei-Yao,Liu Can,Yang Ming-Bo
Derivatization has great potential for the high-value utilization of cellulose by enhancing its processability and functionality. However, due to the low reactivity of natural cellulose, it remains challenging to rapidly prepare cellulose derivatives with high degrees of substitution. The “cavitation effect” of ultrasound can reduce the particle size and crystalline index of cellulose, which provides a possible method for preparing cellulose derivatives. Herein, a feasible method was proposed for efficiently converting regenerated cellulose to cellulose oleate with the assistance of ultrasonic treatment. By adjusting the reaction conditions including ultrasonic intensity, feeding ratios of oleic acid, reaction time, and reaction solvent, a series of cellulose oleates with degrees of substitution ranging from 0.37 to 1.71 were synthesized. Additionally, the effects of different reaction conditions on the chemical structures, crystalline structures, and thermal behaviors were investigated thoroughly. Cellulose oleates with degrees of substitution exceeding 1.23 exhibited amorphous structures and thermoplasticity with glass transition temperatures at 159.8 to 172.6 °C. This study presented a sustainable and practicable method for effectively derivatizing cellulose.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）