ENVIRONMENTAL RESEARCH
·
2022
·
IF 8.431
Xiang Meng,Jianlong Wang,Lejin Xu
To further improve the treatment capacity of actual wastes, H + was introduced into the homogeneous Fenton system as a co-catalyst for dissolution and degradation of the mixed nuclear-grade cationic and anionic exchange resins. The effects of acid type and concentration, catalyst type and concentration, H 2 O 2 dosage, initial temperature, antifoaming agent and resin ratio were studied. The concentration of inorganic acid , type and concentration of catalyst had significant influence on the decomposition of mixed resins. The experimental results showed that when the mixing ratio of resins was 1:1, the initial temperature was 96 ± 1 °C, the amount of H 2 O 2 was 200 mL, and the concentration of H + /Fe 2+ was 1 M/0.1 M, complete dissolution and 79% weight reduction of mixed resins were obtained. Combined with density functional theory (DFT) calculations, cationic exchange resin and anionic exchange resin showed different reactivity in the experiment. Hydroxyl radicals (•OH) tended to attack –SO 3 - groups with more negative charges, and the barrier energy of –SO 3 - ion dissociation was 8.2 kcal/mol, which caused the cationic exchange resin to be easily destroyed. According to the characterization results, the characteristic intermediates were determined, indicating that desulfonation, valence change of nitrogen atom , and cleavage of long-chain carbon skeleton existed during the reaction, but incomplete oxidation still remained.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Dongxue Zhou,Xiangdong Xue,Xing Wang,Qingjie Luan,Ang Li,Liguo Zhang,Baozhen Li,Wenjun Dong,Ge Wang,Changmin Hou
Element doping is an excellent strategy to promote charge separation and reaction kinetics of photocatalyst, which plays significant role in accelerating the sustainable energy development process. Herein, Ni, In co-doped ZnIn 2 S 4 photocatalyst was prepared by a microwave-assisted solvothermal method. The rapid crystallization of ZnIn 2 S 4 resulted in partial In atoms substituted Zn atom during the formation of [ZnS] 4 layer. In doping in tetrahedral Zn sites increases the electron delocalization around In sites, hence reduces the electronic potential wells along Z axis. Ni doping in tetrahedral Zn sites decreases the negative charge on the S sits, which balances the H adsorption/desorption, further boosting the photocatalytic activity. As a result, Ni, In co-doped ZnIn 2 S 4 possess an optimal photocatalytic H 2 evolution property of 21.94 μmol·h −1 , which is nearly 1.8 and 6.1 times of In-ZnIn 2 S 4 (11.78 μmol·h −1 ) and ZnIn 2 S 4 (3.6 μmol·h −1 ).
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Geng Cheng,Zhen Li,Erli Qu,Shan Ren,Dongmei Han,Min Xiao,Shuanjin Wang,Yuezhong Meng
It's of significant importance for the development of proton exchange membranes with low phosphoric acid (PA) uptake, high proton conductivity, better proton conduction stability and low production-costs for high temperature proton exchange membrane fuel cells (HT-PEMFCs). Featured with variable structure and diversified functionality, porous organic networks are newly emerged filler materials for polyelectrolytes in energy conversion field. In this work, a typical Schiff-base type porous polymeric network (SNW-1) with abundant N H sites was synthesized and blended with ether-type polybenzimidazole (PBI) for the first time. The thermal and chemical stability of the as-prepared composite membranes completely satisfy the practical requirements of HT-PEMFCs. The constructed consecutive proton conduction channels endow the composite membranes higher proton conductivity with low PA uptake. When the doping content of SNW-1 reached 30%, the PBI/30%-SNW-1 membrane showed much higher proton conductivity with lower PA uptake (114.0 mS cm −1 , 175.0%) comparing with those of the pristine PBI (67.3 mS cm −1 , 270.0%) at 160 °C. The PBI/ x %-SNW-1 membranes also exhibited better proton conduction stability. After 30 h of long-time evaluation at 140 °C, PBI/30%-SNW-1 composite membrane gives only an 8.47% decay of proton conductivity, which is lower than that of the pristine PBI (12.84%). The preparation procedure of PBI/ x %-SNW-1 composite membranes is simple, which provides a potential pathway for the development of high-performance proton exchange membrane for HT-PEMFCs.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Yong Zeng,Yizhen Chen,Di Sha,Yuchao Wu,Renhui Qiu,Wendi Liu
Thermoplastic polyurethane (TPU) elastomers are widely used in daily products owing to their flexible structures and decent mechanical properties. Vegetable oils (VOs) are promising renewable resources for polymer synthesis with readily availability and abundant derivatives. However, most VO-based polyurethanes are usually thermosets with an unsatisfactory material performance because the C═C bonds are randomly located on triglyceride long chains. Herein, a biobased TPU elastomer was facilely synthesized from palm oil (PO) with desirable and tunable mechanical properties. PO-based diol was synthesized from PO via amidation with 2-(2-hydroxyethylamino)ethanol. The resulting PO diethanolamide (POEA), combined with biobased butane-1,4-diol, was further reacted with 1,6-diisocyanatohexane to prepare PO-based TPU elastomers. The elastomers containing abundant H-bonds from carbamates in the backbone and dangling fatty acid side chains exhibited a microphase separation structure, endowing the elastomers with superior stretchability (up to a strain of 831%), restorability, and self-healing ability. The morphological, melting, crystallization, and rheological behaviors of the elastomers were fully studied. The dynamic and reversible three-dimensional cross-linked network consisting of van der Waals forces and H-bonds was investigated to reveal the formation mechanism of the elastomers.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2021
·
IF 5.302
Fuhai Liu,Maozhong Yi,Liping Ran,Yicheng Ge,Zhe Zhou,Ke Peng
C/C-BN-SiC composite was prepared by ceramic slurry infiltration combined with resin impregnation and carbonization, and the matrix with continuous distributed self-healing phase was obtained. In this study, the kinetic characteristics and oxidation behavior of the composites with various h-BN/SiC ratios in the temperature range of 600∼1300°C were studied by combining the isothermal oxidation test with the kinetic model. The optimal h-BN/SiC ratio balances the thermal stability and fluidity of the oxidized product, which not only has high thermal stability and low oxygen permeability to acts as an oxygen diffusion barrier but also has a certain fluidity to seal defects.
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Xiangdong Long,Jia Wang,Guang Gao,Chao Nie,Peng Sun,Yongjie Xi,Fuwei Li
Direct oxidative amination of the sp3 C–H bond is an attractive synthesis route to obtain amides. Conventional catalytic systems for this transformation are based on transition metals and complicated synthesis processes. Herein, direct and efficient oxidative amination of the methyl C–H bond in a wide range of N-heterocycles to access the corresponding amides over metal-free porous carbon is successfully developed. To understand the fundamental structure–activity relationships of carbon catalysts, the surface functional groups and the graphitization degree of porous carbon have been purposefully tailored through doping with nitrogen or phosphorus. The results of characterization, kinetic studies, liquid-phase adsorption experiments, and theoretical calculations indicate that the high activity of the carbon catalyst is attributed to the synergistic effect of surface acidic functional groups (hydroxyl/carboxylic acid/phosphate) and more graphene edge structures exposed on the surface of carbon materials with a high graphitization degree, in which the role of acidic functional groups is to adsorb the substrate molecule and the role of the graphene edge structure is to activate O2.
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 306
·期 8
·2100159
·
IF 4.367
Hanglan Qin,Yajun Chen,Jieyu Huang,Qufu Wei
Hydrogel, as a promising soft material, possesses many functional advantages such as stretchability, viscoelasticity, and biocompatibility. An advanced electronic platform for strain sensor is constructed by modifying hydrogels with various doping techniques. Herein, a novel flexible conductive hydrogel is synthesized by combination of bacterial cellulose/sodium alginate/polyacrylamide with the polyaniline (BSP-PANI) through multiple intermolecular interactions. In the obtained BSP-PANI hydrogel system, the incorporated BC serves the function of mechanically toughening and the formation of polyaniline conducting network endows the hydrogels electrical conductivity. The assembled hydrogel strain sensor can detect electrical response under different applied strains (1–200%) and monitor human motion in real time. Therefore, it is believed that the BSP-PANI hydrogel prepared by the feasible synergetic strategy proposed in this work has greatly diversified application in smart epidermal sensors and artificial intelligence devices.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Yunwei Liu,Zelin Chen,Chang Liu,Jinfeng Zhang,Wenbin Hu,Yida Deng
We have developed an efficient strategy to synthesize an active and durable electrocatalyst of Pd hydride nanocubes (NCs). Instead of the traditional chemical method, the PdH 0.43 NCs are firstly prepared via a hydrogen diffusion procedure, followed by hydrothermal synthesis of an amorphous CuO layer encapsulating the PdH 0.43 NCs to prevent the hydrogen atoms from escaping. Obvious lattice expansion is demonstrated playing a pivotal role in the enhancement of their oxygen reduction reaction (ORR) activity and durability. The obtained PdH 0.43 @CuO NCs catalysts exhibit an ORR mass activity of 0.18 A mg −1 at 0.90 V versus reversible hydrogen electrode in an alkaline medium, which is about five times higher than that of commercial Pt/C. Accelerated durability tests show that there is only a 32 mV decay in half-wave potential even after 10,000 potential cycles, indicating the excellent stability of PdH 0.43 @CuO NCs. Density functional theory (DFT) calculations also indicate that, compared to Pd, PdH 0.43 has a lower limiting barrier to form OH − during the ORR process. The present study illustrates the importance of lattice expansion caused by hydrogen and offers an available strategy to design highly efficient and durable Pd-based electrocatalysts for alkaline fuel cells.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Peng Hu,Jun Han,Jie Zhou,Hao Wang,Chao Xiong,Hao Liu,Xiantai Zhou,Yongqing Wang,Hongbing Ji
Efficient separation of propylene/propane (C 3 H 6 /C 3 H 8 ) is an imperative and extremely challenging process in the petrochemical industry due to their similar physicochemical characters. Known tactics mainly concentrate on unilateral thermodynamic or kinetic driven. Here, we report the efficient separation of C 3 H 6 /C 3 H 8 through cooperative equilibrium-kinetic synergetic effect in a nodes-engineered Zr-MOF scaffold (1to). The grafted -CF 3 motif with different isomers and resultant aperture chemistry awards 1to a late-model paradigm for efficient separation of C 3 H 6 /C 3 H 8 . Detailly, confined -CF 3 group having the role of H-bonding acceptor can result in improved adsorption enthalpy ( Q st ) of 38.1 kJ mol −1 , ideal adsorbed solution theory (IAST) selectivity of 80 and experimental selectivity of 25, respectively, indicating a marked thermodynamic driven for trapping C 3 H 6 . Besides, the contracted cross-sectional size and eligible pore shape of 1to could be judiciously adjusted through rationally engineering the pore microenvironment, yielding a topmost simulated diffusion selectivity of 408, which was 40.8 times higher than that of the pristine 1 example (10), effectively enabling the swift diffusion behavior of C 3 H 6 . Modeling simulations and breakthrough experiments confirmed the excellent C 3 H 6 /C 3 H 8 separation performance of 1to. This work successfully developed a novel nodes-engineered strategy for C 3 H 6 capture through equilibrium-kinetic synergetic effect, anticipating to set a new benchmark for gas separation and affording constructive guidance for tailoring delicate aperture chemistry.
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Chenxiao Yan,Qingqing Zhang,Heng Gao,Xiong Zheng,Tong Yang,Guoxiang Zheng,Xiaoshun Zhou,Yong Shao
DNA templated dye assemblies pave an easy way to regulate the optical properties of molecular aggregates. G-quadruplexes (G4s) provide versatile DNA platforms for the dye assemblies since their foldings can be easily tuned by cation ions and sequences. In this work, we found that the G4 handedness can be used to control the aggregate chirality of a dye of 3,3′-diethylthiacarbocyanine (DiSC 2 (3)). The left-handed and right-handed G4s can template the concurrent formation of the J- and H-aggregates of DiSC 2 (3) with emergence of the featured absorption spectra. However, the chiral J-aggregate of DiSC 2 (3) can be formed only on the left-handed G4s, while the chiral H-aggregate is otherwise grown only on the right-handed G4s, as confirmed by the induced circular dichroism (ICD) spectra with the characteristic splitting bands. Additionally, these G4s even at tens of nM level are efficient to produce these chiral aggregates, demonstrating the high sensitivity of G4s in creating these optically active dye assemblies. The possible growth sites of the aggregates are proposed by the sequence length-dependent assemblies. Our work will provide a new way to control the chiral assemblies of dye aggregates via the G4 handedness.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 35
·16455-16469
·
IF 3.553
Zhang Zengqi,Wang Qiang,Zhang Mingzhong,Huang Zongxian,Zhuang Shiyu
The filler effect is the most important physical mechanism of mineral admixtures in the early hydration of cement whose chemical properties greatly affect the precipitation of C–S–H. In this study, calcite, strontianite, magnesite, dolomite, quartz, whewellite and whitlockite were selected as the fillers. The morphology and reaction kinetics of synthetic C–S–H precipitated on the surfaces of different fillers were studied via electron microscopy observations and electrical conductivity and ion concentration measurements. The precipitation rate of C–S–H has a positive correlation with the affinity of Ca 2+ for adsorption on the fillers, which can be explained by the nucleation barrier of C–S–H. Extremely ordered honeycomb-like morphology of the C–S–H is found on calcite and strontianite surfaces, while less regular leaf-like or honeycomb-like C–S–H is found on whewellite and whitlockite. The ordered C–S–H pattern is related to the lattice cleavage of the ionic compound filler. In the case of quartz, C–S–H prefers growth along the tangential direction, which is quite different from the normal-direction growth on ionic compounds. The in-plane growth of C–S–H on quartz is believed to be induced by a layer of loosely physically adsorbed Ca 2+ .
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 7
·969-976
·
IF 0
Guangtao Qian,Haiquan Chen,Guangliang Song,Jianan Yao,Mengjie Hu,Chunhai Chen
To introduce intramolecular hydrogen bonds in the polyimides (PIs), 5(6)-amino-2-(5-aminopyridin-2-yl)-benzimidazole (PyPABZ) were designed and synthesized. The intramolecular interaction was indicated by Fourier transform infrared when different copolyimides were prepared with 4,4′-oxydianiline and PyPABZ. These modified poly(benzimidazole imide)s eliminate the problem of high water absorption for benzimidazole (BI)-containing PIs in the materials applications. Moreover, the high packing coefficient and rigidity of these copolyimides caused by the strong intramolecular interaction from the H-bonding and the resulting PIs exhibited outstanding thermal properties such as high glass-transition temperature ( T g ) and low coefficient of thermal expansion. Graphical The polyimides derived from 5(6)-amino-2-(5-aminopyridin-2-yl)-benzimidazole (PIs–PyPABZ) were achieved with the presence of intramolecular hydrogen bonding. These modified co-poly(benzimidazole imide)s exhibited lower H 2 O-absorption and higher thermal properties depending on the intramolecular H-bonding content.
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）