Greenhouse Gases-Science and Technology
·
2022
·Vol. 12
·期 6
·738-750
·
IF 2.518
Jian Liu,Chengdong Kong,Liu Yang,Xiaojiang Wu,Zhongxiao Zhang
In this study, the mass transfer enhancement by nanoparticles during CO 2 absorption process with MDEA solution in a randomly packed tower was investigated. The mass transfer performance of MDEA solution with and without nanoparticles were quantified and analyzed in terms of the volumetric overall mass transfer coefficient ( K G a v ). An enhancement factor ( E ), defined as the ratio of K G a v with and without nanoparticles, was further introduced to evaluate the enhancement effect of the addition of nanoparticles. The effects of TiO 2 nanoparticle concentration, MDEA concentration, liquid flow rate, liquid temperature, inert gas flow rate, and CO 2 loading on K G a v and E were systematically studied in the packed tower. It is found that the maximum value of E can reach 1.37, when the nanoparticle concentration is 0.09 wt %, the liquid flow rate is 21.22 m 3 /m 2 ·h, the liquid temperature is 27°C, the MDEA concentration is 30%, the gas flow rate is 7.58 kmol/m 2 ·h and the CO 2 loading is 0.2 mol CO 2 /mol MDEA. Usually, the K G a v of the MDEA nanofluids can be increased by 10–37% in a randomly packed tower compared to that of the MDEA solution, which is consistent with the results from the bubbling reactors. However, when the CO 2 loading of absorption exceeds 50%, E becomes less than 1.0, which means that high CO 2 loading inhibits the enhancement effect of nanoparticles. In order to predict the mass transfer performance of MDEA nanofluid, a formula correlating E and various dimensionless operating parameters (i.e. L ̂ $\hat{L}$ , T ̂ $\hat{T}$ , C ̂ nf ${\hat{C}}_{{\rm{nf}}}$ and C ̂ MDEA ${\hat{C}}_{{\rm{MDEA}}}$ ) is proposed and fitted with an average absolute deviation of 14%. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.
研究领域:
化学工程
·
环境科学
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DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Yitai Wang,Yinge Bai,Fukang Song,Shaojuan Zeng,Lulu Wang,Xiangping Zhang
Ionic liquids (ILs)-based solvent absorption is a promising green and low regenerative energy consumption technology for CO2 capture. Various functionalized ILs with highly efficient performance have been developed in academia, and the research focuses on thermodynamic properties such as CO2 solubility, gas–liquid equilibrium, and reaction heat. Kinetic studies of CO2 in ILs are also important to evaluate their potential for industrial applications, which need to be studied further. In this work, the mass transfer characteristics of three azole-based IL anhydrous solvents were studied in a wetted-wall column (WWC). At 313.15 K, the total mass transfer coefficient (KG) of fresh [HDBU][Im]/EG, [Cho][Im]/EG, and [Cho][Triz]/EG was 5.40, 2.32, and 0.80 mmol/(m2·s·kPa), respectively. The KG of the three solvents increased along with increase in the temperature. Conversely, when the CO2 loading in the solvent increased, KG decreased. At the initial stage of absorption, the mass transfer resistance of [HDBU][Im]/EG was mainly in the gas phase and then gradually changed to liquid phase. However, due to the excessive viscosity of [Cho][Im]/EG and [Cho][Triz]/EG, the mass transfer resistance was mainly concentrated in the liquid phase. The enhancement factor (E) of [HDBU][Im]/EG was higher than 159, indicating that it had good chemical reaction ability, thereby improving the mass transfer ability. The KG of [HDBU][Im]/EG is 92.12, 307.01, and 117.48% higher than MEA/H2O, MDEA/PZ/H2O, and MEA/AEEA/H2O at 313.15 K, respectively. This work showed that [HDBU][Im]/EG had a good mass transfer performance and great potential in future industrial applications. At the same time, the mass transfer law was summarized to provide theoretical support for CO2 capture technology and reactor design.
研究领域:
化学工程
·
环境科学
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Xin Lin,Li-Jun Li,He-Yuan-Xi Guo,Rui Li,Jun Feng
In this paper, 3D nano-silver trees/sea urchin-like gold Surface Enhanced Raman Spectroscopy (SERS) substrates were prepared by chemical reduction method, characterized by SEM, EDS, UV–Vis and XRD et.al, and the preparation process was optimized using Rhodamine B (RB) as the Raman signal molecule. The SERS characteristics of Uric Acid on this substrate were investigated and the results showed that the SERS substrate had a Raman enhancement factor of 1.9 × 10 7 for RB, and also had a significant Raman enhancement effect on Uric Acid. The SERS intensity ( I SERS ) at 1400 cm −1 showed a good linear relationship with the logarithm value of uric acid concentration (log C ) between the range of 5 × 10 −4 M to 1 × 10 −7 M. The linear fitting equation was I SERS = 890 (log C ) + 8066 (R 2 = 0.983), and the LOD = 2.8 × 10 − 8 M. The spiked test was performed in human serum with recoveries ranging from 82.86% to 125.13% and RSD (n = 3) < 3.5%.
研究领域:
分析化学
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材料科学
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医学诊断
✓ 已验证
DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2019
·Vol. 76
·期 4
·1363-1370
·
IF 3.255
Chengfeng Lei,Shili Yang,Wenxiao Lei,Innocent Nyamwasa,Jia Hu,Xiulian Sun
BACKGROUND Baculoviruses provide long-lasting control of crop pests and are harmless to humans and non-target animals, making them attractive bioinsecticides. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) has a wide-host range and is one such commercial bioinsecticide, but its low infectivity to older larvae and less-sensitive species precludes its large-scale application. We sought to improve the infectivity of AcMNPV. RESULTS Two enhancing factors, the truncated enhancin from Agrotis segetum granulovirus and GP37 from Cydia pomonella granulovirus, were expressed in fusion with the N-terminal and middle domain of the polyhedrin envelope protein of AcMNPV. Western blotting and immunoelectron microscopy analysis indicated that the enhancing factors were expressed on the occlusion bodies of the resulting AcMNPV variants. Bioassays showed that the median lethal doses of the recombinant viruses were 3.9-fold to 7.4-fold lower than those of the wild-type virus against the second and fourth instar of Spodoptera exigua larvae. The yields of occlusion bodies from the two recombinants in S. exigua larvae were comparable with those of the wild-type virus both in vitro and in vivo . Further bioassays showed that the AcMNPV variants fusing the enhancing factors were incapable of infecting the second instar larvae of S. litura , Helicoverpa armigera , and Pyrausta nubilalis , which were not sensitive to the wild-type AcMNPV. CONCLUSION These genetically modified AcMNPV variants exhibited an enhanced infectivity and may offer better baculovirus control of crop pests. © 2019 Society of Chemical Industry
研究领域:
病毒学
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昆虫学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2016
·Vol. 45
·期 4
·2299-2304
·
IF 1.491
Song Meng,Xu Peng,Han Lijing,Yi Lan,Wang Xu,Li Zhenhua,Shang Xuefu,Wang Xiumin,Wu Huizhen,Zhao
Pei,Song Yenan,Wang Miao
We present a three-dimensionally configured cathode with enhanced field-emission performance formed by combining carbon nanotube (CNT) emitters with a nickel foam (NiF) substrate via a conventional screen-printing technique. The CNT/NiF cathode has low turn-on electric field of 0.53 V μ m −1 (with current density of 10 μ A cm −2 ) and threshold electric field of 0.87 V μ m −1 (with current density of 0.1 mA cm −2 ), and a very high field enhancement factor of 1.4 × 10 4 . The porous structure of the NiF substrate can greatly improve the field-emission properties due to its large specific surface area that can accommodate more CNTs and increase the emitter density, as well as its high electrical and thermal conductivities that facilitate current transition and heat dissipation in the cathode. Most importantly, the local electric field was also enhanced by the multistage effect resulting from the rough metal surface, which furthermore leads to a high field enhancement factor. We believe that this improved field-emission performance makes such cathodes promising candidates for use in various field-emission applications.
研究领域:
材料科学
·
电子工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY
·
2023
·Vol. 124
·期 1
·e27327
·
IF 2.2
Jiaxi Yang,Dan Gao,Yong Pan,Yuanyuan Cao,Heng Zhang,Yating Chen
The combination of zeolitic imidazolate framework-8 (ZIF-8) and ionic liquids (ILs) to create porous ionic liquids (PILs) is highly significant for efficient carbon dioxide (CO 2 ) capture and the advancement of carbon capture, utilization, and storage (CCUS) technologies. To further investigate the CO 2 capture characteristics of different PILs, two different-sized ZIF-8 structures and two functionalized ILs were prepared. Additionally, the enhancement factor of the reaction process was calculated using the dual-film theory and mass transfer coefficient. The results demonstrated that the original [PMIm]Cl had low CO 2 absorption capacity at ambient temperature and pressure, whereas the functionalized ILs had a maximum CO 2 capture capacity of approximately .31 mol/mol, with the 20 wt% concentration of tetraethylene pentamine-2-methylimidazole ([TEP][MIm]) exhibiting the highest CO 2 capture capacity of around 1.93 mol/mol. The synthesized PILs demonstrated a maximum CO 2 capture capacity of approximately 2.22 and 2.16 mol/mol at 20 and 10 wt% ionic concentrations, respectively, with a porous ionic liquid addition of 1.0/100 g. The corresponding enhancement factors were 1.53 and 1.59, respectively. These findings have significant implications for CCUS technology.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Yunrui Han,Yingkuan Han,Qihang He,Hong Liu,Yu Zhang,Lin Han
Low-concentration molecular detection is of great value in chemical analysis, environmental monitoring, biological analysis, and other trace detection fields. Surface-enhanced Raman scattering (SERS) is widely used in the analysis of low-concentration molecules with great potential for biological detection due to nondestructive measurement. However, detection uniformity and repeatability are challenges in the application of SERS, especially as regards ultrasensitive detection. Here, a AgNPs@LIG SERS chip with excellent sensitivity and uniformity was fabricated by electroplating Ag nanoparticles (AgNPs) on a laser-induced graphene (LIG) surface prepared on a polyimide (PI) film, which realized large-scale production with controllable shape and area. Such an SERS chip features a limit of detection (LOD) of 10–14 M, an enhancement factor (EF) of 3 × 1010, and fine uniformity (∼9.6% relative standard deviation) for rhodamine 6G, benefiting from excellent local electromagnetic field enhancement generated by the gap of AgNPs and excellent performance of porous LIG. Finally, the chip was applied to the detection of melamine with the LOD of 10–9 M, which confirmed the potential application value of the SERS chip for pollutant analysis. In addition, the preparation of the composite SERS chip is simple for mass production, which provides great potential for the development of ultrasensitive SERS biosensors for various biological and chemical analyses.
研究领域:
化学分析
·
环境监测
·
生物分析
✓ 已验证
产品关联
DOI
高影响因子
Biosensors-Basel
·
2023
·Vol. 13
·期 8
·825
·
IF 5.4
Zixuan Wu,Jianxun Liu,Zhenming Wang,Lei Chen,Yiwei Xu,Zongjun Ma,Delai Kong,Dan Luo,Yan Jun Liu
We demonstrated a low-cost, highly sensitive hybrid Ag-Cu substrate with enhanced absorption for the excitation laser beam via the nanosphere lithography technique. The hybrid Ag-Cu surface-enhanced Raman spectroscopy (SERS) substrate consists of a Cu nanoarray covered with Ag nanoparticles. The geometry of the deposited Cu nanoarray is precisely determined through a self-assembly nanosphere etching process, resulting in optimized absorption for the excitation laser beam. Further Raman enhancement is achieved by incorporating plasmonic hotspots formed by dense Ag nanoparticles, grown by immersing the prepared Cu nanoarray in a silver nitrate solution. The structural design enables analytical enhancement factor of hybrid Ag-Cu SERS substrates of 1.13 × 105. The Ag-Cu SERS substrates exhibit a highly sensitive and reproducible SERS activity, with a low detection limit of 10−13M for Rhodamine 6G detection and 10−9M for 4,4′-Bipyridine. Our strategy could pave an effective and promising approach for SERS-based rapid detection in biosensors, environmental monitoring and food safety.Keywords:SERS;enhancement factor;hot spot;self-assembly;nanosphere lithography
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Yuan Wang,Lei Feng,Haiyan Zhu,Hongyan Miao,Ying Li,Xuefeng Liu,Gang Shi
The fluorescence intensity of the ring-opened merocyanine (MC) form of spiropyran can be enhanced by metal nanostructures. However, direct contact between spiropyran and the metal results in fluorescence quenching, which will reduce the enhancement amplitude of MC fluorescence. Here, Ag nanoparticles (NPs), a TiO2 dielectric layer, a poly(methyl methacrylate)-spiropyran (PMMA-SP) layer, and Au shell-isolated NPs with SiO2 shells (Au@SiO2) are successively assembled on a Si wafer with micropyramids and nanoholes (Siph). The hierarchical structure of this substrate is similar to insects’ compound eyes with nano- and microstructures, which can reduce the reflection of incident light. Meanwhile, the Au/Ag-coupled plasmonic nanocavities can enhance the intensity of a local electromagnetic (EM) field. In addition, TiO2 and SiO2 layers can avoid the nonradiative energy transfer caused by the direct contact between spiropyan and the metal. Based on the above advantages, the fluorescence enhancement factor (EF) of this substrate is as high as 195, which is the maximum reported so far. Zn2+, Cu2+, and Sn2+ can also be detected on Siph/TiO2/PMMA-SP/Au@SiO2, whose detection limits are 0.054, 0.038, and 0.049 μM, respectively. Furthermore, this substrate can be reused to detect metal ions by taking advantage of the reversible isomerization of spiropyran. The bioinspired substrate has positive significance in improving the fluorescence intensity of MC, and its lack of specific recognition ability for metal ions is expected to be further improved by molecular modification of spiropyran.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2018
·
IF 2.795
Jing Zhu,Yubo Wang,Junsu Jin,Liren Qin
The solubility of o -aminobenzamide ( o -AB) and its mixture with o -nitrobenzoic acid ( o -NBA) in subcritical 1,1,1,2-tetrafluoroethane (R134a) was measured at temperatures of 308, 318, 328 K and pressure range from 5.0 to 15.0 MPa with static method. Then the solubility of o -AB and o -NBA in subcritical R134a binary and ternary system were compared and investigated from the view of solvent density, solvent polarity, and interaction between solvent and solute. In order to evaluate the effect of co-solute on solubility of solute, enhancement factor ( EF ), separation factor ( SF ), separation efficiency ( SE ), and the solubility enhancement coefficient ( α ) were defined and calculated. In addition, empirical models, including Chrastil, A–L, K–J, S–S, and M–T models applying for binary system, with González, Sovová, M–M–T, and Z–J models applying for ternary system, are used for correlating the experimental solubility. The satisfactory correlated results were obtained with the AARD range from 2.16% to 4.75%.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
OPTICS EXPRESS
·
2020
·Vol. 28
·期 14
·20817-20829
·
IF 3.669
Jun Dong,Yi Cao,Qingyan Han,Yongkai Wang,Minghan Qi,Wenwen Zhang,Lin Qiao,Jianxia Qi,Wei Gao
The monolayer graphene-noble metallic nanostructure hybrid system with excellent optical characteristic, which is deserved pay attentions in the study of surface-enhanced Raman scattering spectroscopy. In this work, a hybrid sandwich structure is designed to transfer single-layer graphene to the surface of discs substrate covered by silver film and assembly of the dense Au nanoparticles (AuNPs). Blu-ray disc has a cycle density of approximately 5.7 times that of DVD-R due to the different storage capacities of these optical discs. In the research, enhancement effects have been explored for two different periodic grating structures. Compared to spectra of Si/G structure, Graphene Raman spectra from Blu-grating/AuNPs/G structure and Blu-grating/G/AuNPs enhancement multiples at the 2D peak position possesses different Raman responses of 1.09 and 2.51 times, respectively. The sandwich hybrid structure of Ag grating/graphene/AuNPs obtains a Raman enhancement factor (EF) of 6.2×108 for Rhodamine 6G and surface-enhanced Raman Scattering(SERS) detection limit of 0.1 nM. These findings can be attributed to the electric field enhancement of the hybrid structure and the chemical enhancement of graphene. This study provides a new approach for SERS detection and offers a new technique for designing SERS sensors with grapheme-plasmon hybrid structures.
研究领域:
光学
·
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Lan Zhang,Tingting Zhang,Shiying Wu,Lujie Li,Wei Li,Lingling Wang,Weihua Li,Xianhuai Huang,Jiansheng Li,Rui Lu
Although surface-enhanced Raman scattering (SERS) is a powerful spectral analysis technique, its practical application is restricted due to the poor chemical stability of some noble metal nanoparticles. In this work, Ag@ZIF-8 nanocomposites with different ZIF-8 core-shell thicknesses were prepared by coating AgNP surfaces with polyvinylpyrrolidone and adjusting the dosage of zinc nitrate and 2-methylimidazole. Several characterizations have confirmed that the Ag@ZIF-8 nanocomposites was successfully prepared. Based on transmission electron microscopy images and SERS spectral intensity, it was determined that Ag@ZIF-8 nanocomposites with a ZIF-8 shell thickness of 30 nm exhibited optimal SERS performance. As a result of evaluating the uniformity and stability of the composite with 4-ATP as the probe molecule, it showed a relative standard deviation of 6.91 % and a decrease in SERS intensity of 4.5 % after 28 days. Based on the results obtained with Ag@ZIF-8 nanocomposites as the SERS substrate, the detection limits of 4-mercaptopyridine and thiram were as low as 5.87×10 −9 M and 6.61×10 −8 M, respectively. Furthermore, the finite-difference time-domain simulation reveals an enhancement factor of 2.6×10 6 , which is in good agreement with the experimental value of 1.8×10 6 , confirming its effectiveness as a SERS substrate.
研究领域:
材料科学
·
分析化学
·
环境科学
✓ 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）