OPTIK
·
2020
·
IF 2.187
Tongpeng Zhao,Shaohua Ji,Degao Zhong,Fei Teng,Shakir Ullah,Siyuan Hu,Jie Tang,Bing Teng
The organic nonlinear optical (NLO) material N, N-dimethyl-4-[2-(2-quinolyl) vinyl] aniline (DADMQ) has been synthesized and high-quality single crystal with the dimension of 8 × 1 × 0.5 mm 3 was grown from methanol solvent by slow cooling method for the first time. Single crystal and powder XRD studies show that DADMQ crystal belongs to the orthorhombic space group Pna2 1 . All the functional groups and structure of the synthetic material can be determined from FT-IR and 1 H NMR spectral analyses. The thermal properties can be studied through TG/DTG and DSC analyses, and its melting point is confirmed at 184.9 ℃. Some critical optical characteristics like the optical transmittance, optical absorption coefficient (α), energy band gap ( E g ), cut-off wavelength (λ max ) and extinction coefficient (κ) can be carried out through UV–vis-NIR spectral analysis. The dielectric features of the title crystal have also been measured. Furthermore, there is a blue emission appeared at 493 nm through PL spectral analysis. The second harmonic generation (SHG) efficiency of the title crystal has been measured, which indicates that DADMQ has 3.64 times greater than KDP crystal.
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高影响因子
Journal of Rubber Research
·
2019
·Vol. 23
·期 1
·41-46
·
IF 0.281
Liao Xiao-Xue,Wei Yan-Chan,Zhang Hui-Feng,Zheng Ting-Ting,Luo Ming-Chao,Liao Shuangquan
Waste rubber with three-dimensional structure is insoluble and non-melting, which creates recycling problem. The technique called “high-pressure high-temperature sintering” (HPHTS) can convert vulcanized rubber powder into usable rubber products. However, reversion occurs when vulcanizates are exposed to a prolonged treatment at high temperature. This reversion results in the decrease of mechanical properties of sintered waste rubber powder (WRP) samples. To address this problem, a method of enhancing the mechanical properties of sintered WRP by incorporating different content of maleic anhydride (MA) and N , N ′- m -phenylene bismaleimide (BMI) is discussed in this paper. The results show that BMI and MA can slow down the formation of the conjugated double bonds. Through Diels–Alder reaction, BMI inhibits conjugated double bonds formation and improves the adhesion between particles and particles, which is beneficial to improvement of final properties. Therefore, BMI improves the mechanical properties of sintered WRP greatly.
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JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Guojuan Qu,Peng Jia,Shuai Tang,Md. Nahid Pervez,Yixiong Pang,Bin Li,Chengjin Cao,Yaping Zhao
Understanding the role of intrinsic defects and nonmetallic heteroatom doping defects in activating peroxymonosulfate (PMS) and subsequently degrading endocrine-disrupting compounds is crucial for designing more efficient carbon catalysts. Therefore, we synthesized N-rich carbon nanosheets (NCs) through pyrolysis of a glutamic acid and melamine mixture and utilized them to activate PMS for bisphenol A (BPA) degradation. Different weight ratios of the above mixtures were allowed for manipulating NCs' defect level and N configuration. The reaction rate constant ( k ) was significantly positively correlated with the pyridinic and pyrrolic N content, and negatively and weakly positively correlated with graphite N and intrinsic defects, respectively. These findings suggest pyridinic and pyrrolic N, rather than graphitic N and intrinsic defects, enhance PMS activation to generate reactive oxygen species (specifically O •–2 and 1 O 2 ) and oxidize BPA. The NC-activated PMS system with the highest N content (17.9 atom%) demonstrated a remarkably high k (0.127 min −1 ) using minimal concentrations of PMS (0.4 mM) and NC (0.15 g/L), highlighting the system's efficiency. Excess halide anions led to significantly increased k with only a limited formation of trichloromethane (disinfection byproducts) in presence of 100 mM Cl − . This study offers novel perspectives on identifying catalytic sites within N-doped carbonaceous materials .
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PubMed
高影响因子
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
·
2023
·
IF 3.3
Xueying Wang,Qian Ma,Qi Zhang,Yi Wang,Lingyu Li,Dongheng Zhao,Zhiqiang Liu
Porous double-channel α-Fe 2 O 3 /SnO 2 heterostructures with tunable surface/interface transport mechanism have been originally fabricated by the electrospinning and subsequent calcination process. With the increase of Sn content from 0 to 5 mol%, the morphology of α-Fe 2 O 3 -based materials changed from porous fibers to ribbons with both sides curled inward. Double-channel structure can provide more active sites and enhanced adsorption capacity with the large specific surface areas of 233.2 m 2 /g. The optimal α-Fe 2 O 3 /SnO 2 composites exhibit the highest response value (32.38) and fastest response/recovery times (33/58 s) than those of other samples to 100 ppm N,N-dimethylformamide (DMF) at 360 °C. Meanwhile, good cycling and long-term stability and high gas selectivity of the composites are conductive to the feasible detection to DMF under high temperature (≥360 °C) condition. The enhanced gas-sensitive properties of α-Fe 2 O 3 /SnO 2 composites at high temperature are closely related to phase composition, unique morphology, efficient n-n heterojunction and accelerated surface/interface charge transfer process. Significantly, the porous double-channel α-Fe 2 O 3 /SnO 2 composite is expected to be a potential candidate for DMF vapor detection in the dye or pesticide industry to prevent DMF explosion under high temperature conditions in the future.
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高影响因子
COMBUSTION AND FLAME
·
2018
·
IF 4.494
Guoqing Wang,Yuyang Li,Wenhao Yuan,Yizun Wang,Zhenbiao Zhou,Yingzheng Liu,Jianghuai Cai
Bio-butanol is an important alternative fuel and has many advantages in engine combustion . In the present work, laminar flame propagation of n- butanol/air and n- butanol/(14% O 2 /86% He) mixtures was investigated using a constant-volume combustion vessel at the unburnt temperature of 423 K, initial pressures of 1–20 atm and a series of equivalence ratios. Flame instabilities of n -butanol, including cellular instability and pulsating instability, were studied based on flame morphology. The unsteady transition from weak flame to normal flame was investigated based on the flame trajectories and this phenomenon became less perceptible in the flame with stronger combustion intensity and smaller Lewis number. The accelerated laminar burning velocity (LBV), thickened flame thickness, larger Markstein length and Markstein number indicate that the thermal diffusivity of n- butanol/O 2 /He flames are greatly enhanced by helium addition. The smaller densities and lower reactant concentrations result in the smaller laminar burning fluxes of n- butanol/O 2 /He flames than those of n -butanol/air flames. The high temperature kinetic model of n -butanol reported by Cai et al. was further developed with recent theoretical progresses on n -butanol reactions. The updated high temperature model was validated on the present experimental data and a vast amount of previous n -butanol combustion data . Sensitivity analysis was performed using the updated model under wide pressure and equivalence ratio ranges. The similarity in the sensitivities indicates that the sensitive reactions in n- butanol/air flames can be validated by using n- butanol/O 2 /He flames, which greatly compensates the problem that the n- butanol/air flames are susceptible to flame instabilities at high pressures. The weaker pressure dependence of the LBVs of n -butanol/O 2 /He flames indicates that their flame chemistry changes less to resist the pressure variation.
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高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2018
·
IF 2.631
Xiao Feng,Ali Farajtabar,Hu Lin,Gaoquan Chen,Zhiying Wang,Xinbao Li,Hongkun Zhao
The D-tryptophan solubility in aqueous solutions of methanol, ethanol, isopropanol and N , N -dimethylformamide (DMF) was measured by the saturation shake-flask method at temperatures ranging from 283.15 K to 333.15 K. The maximum solubility was found in water for alcohol (1) + water (2) mixtures, and in neat DMF for DMF (1) + water (2) mixture. When the same temperature and mass fraction of the water is given, the highest mole fraction solubility of D-tryptophan was found in (DMF + water). The solid phases were tested by X-ray powder diffraction (XPRD) showing no polymorphic transformation, solvate formation or crystal transition. Three solubility models, i.e. the Jouyban-Acree, van’t Hoff-Jouyban-Acree and Apelblat-Jouyban-Acree were employed to correlate the experimental solubility values so as to obtain thermodynamic parameters. The RAD and RMSD data were no more than 1.65% and 9.40 × 10 −5 , respectively. Linear solvation energy relationship analysis based on Kamlet-Taft parameters indicated that the variation of D-tryptophan solubility depended on π ∗ for methanol (ethanol, isopropanol) (1) + water (2), and cavity term for DMF (1) + water (2). The preferential solvation parameters ( δx 1,3 ) for methanol, ethanol, isopropanol and DMF derived by means of the inverse Kirkwood–Buff integrals were negative in the four solvent mixtures with intermediate and alcohol-rich compositions, which indicated that D-tryptophan was preferentially solvated by water. The higher solvation by water could be explained in terms of the higher acidic behaviour of the solvents interacting with the Lewis basic groups of the D-tryptophan. However D-tryptophan is preferentially solvated neither by water nor by DMF in DMF + water mixture.
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高影响因子
Frontiers of Chemical Science and Engineering
·
2018
·Vol. 12
·期 3
·457-466
·
IF 2.643
Shang Jiaojiao,Yao Guo,Guo Ronghui,Zheng Wei,Gu Long,Lan Jianwu
Biodegradable poly(ether-imide-ester) elastomers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N ′, N -bis(2-carboxyethyl)- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystallinities, thermal stabilities, mechanical properties, hydrophilicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly (ether-ester) exhibited monoclinic chain packing. Increasing the amount of aromatic bisimide moieties in the poly (ether-ester) reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly(ether-ester) backbones endowed the elastomers with improved biodegradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.
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高影响因子
Catalysis Science & Technology
·
2016
·Vol. 6
·期 16
·6217-6225
·
IF 5.287
Zuojun Wei,Jiongtao Lou,Zhenbin Li,Yingxin Liu
An efficient catalysis system composed of a Lewis–Brønsted acid mixture and Ru/C using N,N-dimethylformamide as a solvent was developed for the one-pot conversion of fructose to 2,5-dimethylfuran (2,5-DMF) via the dehydration/hydrogenolysis sequence. The effects of various reaction parameters, such as solvent, catalyst type, catalyst loading, reaction pressure, temperature and time, on single fructose dehydration, 5-hydroxymethylfurfural (5-HMF) hydrogenolysis and the one-pot conversion of fructose to 2,5-DMF were systematically investigated. The results showed that 2,5-DMF could be successfully produced with a yield as high as 66.3 mol% by using a one-pot method directly from fructose under the optimized reaction conditions, which is by far the highest yield ever reported for the production of 2,5-DMF from fructose through a one-pot strategy. The Ru/C catalyst could be reused at least three times with a slight decrease in 2,5-DMF yield.
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高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 20
·9873-9881
·
IF 8.867
Mingyu Tong,Shengwen Liu,Xian Zhang,Tianxing Wu,Haimin Zhang,Guozhong Wang,Yunxia Zhang,Xiaoguang Zhu,Huijun Zhao
Due to their controllable morphologies, tunable porous structures, diverse compositions and easy fabrication, metal–organic frameworks (MOFs) are an ideal class of precursor material to develop high performance carbon-based materials for energy applications. In this work, two-dimensional (2D) Co/Ni MOFs nanosheets with a molar ratio of Co2+ to Ni2+ of 1 : 1 were first synthesized at room temperature using thiophene-2,5-dicarboxylate (Tdc) and 4,4′-bipyridine (4,4′-Bpy) as organic linkers. As a precursor material, the as-synthesized 2D Co/Ni MOFs nanosheets were further pyrolized at 550 °C in N2 atmosphere to incorporate 2D CoNi alloy nanoparticles into S, N-doped carbon nanosheets (CoNi@SNC) with a surface area of 224 m2 g−1, a porous structure, and good conductivity. Interestingly, it was found that the 2D Co/Ni MOFs nanosheets can be directly used as electrode materials for supercapacitors, delivering a specific capacitance of 312 F g−1 at 1 A g−1, whereas CoNi@SNC derived from its MOFs precursor as an electrode material for supercapacitors exhibits a much higher specific capacitance (1970, 1897 and 1730 F g−1 at 1, 2, 5 A g−1, respectively) with long cycling life (retaining 95.1% of the value at 10 A g−1 after 3000 cycles) and excellent rate capability at a high charge/discharge current. Further, an asymmetric supercapacitor device was constructed with CoNi@SNC as the positive electrode and active carbon as the negative electrode, exhibiting an energy density of 55.7 W h kg−1 at a power density of 0.8 kW kg−1 with lifetime stability up to 4000 charge–discharge cycles (capacitance retention of ∼90.6%). The results demonstrate that electrochemical activation-generated CoNi oxides/oxyhydroxides on the surface of the CoNi alloy nanoparticles in alkaline electrolyte during electrochemical measurements are the electrochemical active species of the CoNi@SNC-constructed supercapacitor. Additionally, the high performance of the CoNi@SNC-constructed supercapacitor can be collectively attributed to its relatively high surface area, which is favourable for the exposure of electrochemical active sites; its porous structure, which promotes redox-related mass transport; and the combination of CoNi alloy nanoparticles with graphitic carbon, which functions as an electron collector to improve electron transfer.
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高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Jiangbo Xi,Chuyi Xie,Yan Zhang,Lu Wang,Jian Xiao,Xianming Duan,Jinghua Ren,Fei Xiao,Shuai Wang
The development of carbon based hollow-structured nanospheres (HNSs) materials has stimulated growing interest due to their controllable structure, high specific surface area, large void space, enhanced mass transport, and good biocompatibility. The incorporation of functional nanomaterials into their core and/or shell opens new horizons in designing functionalized HNSs for a wider spectrum of promising applications. In this work, we report a new type of functionalized HNSs based on Pd nanoparticles (NPs) decorated double shell structured N-doped graphene quantum dots (NGQDs)@N-doped carbon (NC) HNSs, with ultrafine Pd NPs and “nanozyme” NGQDs as dual signal-amplifying nanoprobes, and explore their promising application as a highly efficient electrocatalyst in electrochemical sensing of a newly emerging biomarker, i.e., hydrogen peroxide (H2O2), for cancer detection. Due to the synergistic effect of the robust and conductive HNS supports and catalytically active Pd NPs and NGQD in facilitating electron transfer, the NGQD@NC@Pd HNS hybrid material exhibits high electrocatalytic activity toward the direct reduction of H2O2 and can promote the electrochemical reduction reaction of H2O2 at a favorable potential of 0 V, which effectively restrains the redox of most electroactive species in physiological samples and eliminates interference signals. The resultant electrochemical H2O2 biosensor based hybrid HNSs materials demonstrates attractive performance, including low detection limit down to nanomole level, short response time within 2 s, as well as high sensitivity, reproducibility, selectivity, and stability, and have been used in real-time tracking of trace amounts of H2O2 secreted from different living cancer cells in a normal state and treated with chemotherapy and radiotherapy.
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PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2013
·Vol. 36
·期 8
·1343-1348
·
IF 2.591
Qiuyun Wang,Yajin Xiong,Baozhu Lu,Jun Fan,Sheng Zhang,Shengrun Zheng,Weiguang Zhang
N -(2,4-dinitrophenyl)-proline and N -(2,4-dinitrophenyl)-serine were enantiomerically resolved on the BSA chiral stationary phase by HPLC in reversed-phase mode. Effects of chromatographic conditions on enantioseparation and elution order have been investigated in detail. For these two samples, reversal of enantiomer elution order was observed by changing buffer pH, the content of acetonitrile, or alcohol modifiers in mobile phase, which is firstly reported in the BSA chiral stationary phase studies. More interestingly, combined effect between buffer pH and the content of acetonitrile was also observed. In addition, coelution range of enantiomers varied along with the content of acetonitrile in mobile phase.
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PubMed
高影响因子
Analytical Methods
·
2013
·Vol. 5
·期 20
·5444-5449
·
IF 1.855
Xin Wang,Yunchun Liu,Lianbing Ren,Hengye Li,Zhen Liu
A new hydrophilic boronate affinity monolithic capillary was synthesized for the selective capture of cis-diol biomolecules including glycoproteins and nucleosides, using (3-acrylamidophenyl)boronic acid (APBA) and N,N-methylenebisacrylamide (MBAA) as the functional monomer and cross-linker, respectively. A comparison with other compositionally similar monolithic capillaries was carried out in terms of reversed-phase retention, selectivity, binding capacity and binding pH. The poly(APBA-co-MBAA) monolithic capillary exhibited notably different properties. As both the functional monomer and the cross-linker are hydrophilic, the monolith capillary showed suppressed reversed-phase retention and as a result excellent selectivity toward both nucleosides and glycoproteins was observed. It exhibited the highest binding capacity as compared with other compositionally similar monolithic capillaries. Besides, because of the lower pKa value of APBA, the monolithic capillary was able to selectively capture nucleosides at near-physiological pH.
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高影响因子
危险品化学品经营许可证（带存储）