Sclerotinia sclerotiorum is a typical necrotrophic plant pathogenic fungus, which has a wide host range and can cause a variety of diseases, leading to serious loss of agricultural production around ...the world. It is difficult to control and completely eliminate the characteristics, chemical control methods is not ideal. Therefore, it is very important to know the pathogenic mechanism of S. sclerotiorum for improving host living environment, relieving agricultural pressure and promoting economic development. In this paper, the life cycle of S. sclerotiorum is introduced to understand the whole process of S. sclerotiorum infection. Through the analysis of the pathogenic mechanism, this paper summarized the reported content, mainly focused on the oxalic acid, cell wall degrading enzyme and effector protein in the process of infection and its mechanism. Besides, recent studies reported virulence-related genes in S. sclerotiorum have been summarized in the paper. According to analysis, those genes were related to the growth and development of the hypha and appressorium, the signaling and regulatory factors of S. sclerotiorum and so on, to further influence the ability to infect the host critically. The application of host-induced gene silencing (HIGS)is considered as a potential effective tool to control various fungi in crops, which provides an important reference for the study of pathogenesis and green control of S. sclerotiorum .
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The Joule–Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage (CCS). In this work, a set ...of apparatus was set up to determine the Joule–Thomson effect of binary mixtures (CO2 + H2). The accuracy of the apparatus was verified by comparing with the experimental data of carbon dioxide. The Joule–Thomson coefficients (μJT) for (CO2 + H2) binary mixtures with mole fractions of carbon dioxide (xCO2 = 0.1, 0.26, 0.5, 0.86, 0.94) along six isotherms at various pressures were measured. Five equations of state EOSs (PR, SRK, PR, BWR and GERG-2008 equation) were used to calculate the μJT for both pure systems and binary systems, among which the GERG-2008 predicted best with a wide range of pressure and temperature. Moreover, the Joule–Thomson inversion curves (JTIC) were calculated with five equations of state. A comparison was made between experimental data and predicted data for the inversion curve of CO2. The investigated EOSs show a similar prediction of the low-temperature branch of the JTIC for both pure and binary systems, except for the BWRS equation of state. Among all the equations, SRK has the most similar result to GERG-2008 for predicting JTIC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
A key issue in attaining highly efficient supported catalysts for the hydrogenation of unsaturated polymers arises from the entanglement between the number of exposed active sites and the severe ...internal mass transfer limitation caused by their large molecular size. Hence, an ultrasmall N-doped carbon nanosphere with Ni NPs and CQDs embedded (Ni-CQDs/NCNs) was reasonably constructed by low-temperature (400 °C) pyrolysis of the precursor CQDs@Nano-Ni-ZIFs. As-prepared Ni-CQDs/NCNs exhibited superior catalytic activity to a commercial 10% Pd/C catalyst in petroleum resin hydrogenation under a low temperature of 150 °C, which is 100 and 60 °C lower than that of previously reported Ni- and Pd-based catalysts, respectively. The excellent catalytic activity of Ni-CQDs/NCNs mainly contributes to the following factors: first, its ultrasmall structure (ca. 50 nm) eliminates the internal mass transfer limitation; second, the CQDs and N-doped carbon matrix stabilize the 53.1 wt % high-loading Ni NPs at a small size of 5.6 nm, providing abundant active sites; and third, the electronic regulation of N-doped carbon enhances the intrinsic activity of Ni, which was revealed by the experiments and DFT calculations. Besides, Ni-CQDs/NCNs exhibits long-term stability and appreciable magnetic separation performance, making it a considerable candidate for industrial application. This work not only offers a facile approach to prepare nano MOF-derived catalysts but also gives helpful instruction to the rational design of heterogeneous catalysts for the reaction involving large molecules.
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IJS, KILJ, NUK, PNG, UL, UM
A facile and high yield strategy for the large-scale production of highly active Co/NCNTs catalyst transformed from zeolitic imidazolate frameworks have been developed. Benefiting from the high ...density and accessible active sites induced by the high-loaded Co NPs in small size and the open carbon nanotube structure, Co/NCNTs exhibits high activity in hydrogenation of aromatic hydrocarbon resin (AHCR) at mild condition. Furthermore, a combination of kinetic experiments and density functional theory calculations were conducted to provide insight into the mechanism of AHCR hydrogenation.
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•Facile and green approach for the large-scale synthesis of ZIF-derived Co/NCNTs catalyst.•Co/NCNTs exhibit superior activity to the commercial 5 wt% Pd/C in AHCR hydrogenation.•Kinetic study on AHCR hydrogenation has been conducted based on the ER and LHHW models.•DFT calculations further corroborated the LHHW mechanism.•Surface reaction between the chemisorbed AHCR and hydrogen is the rate-determining step.
The large-scale synthesis of transition metal catalysts with high performance and their catalytic mechanism for hydrogenation is of great importance for the development of a cost-effective alternative to noble metal catalysts. Herein, we report a facile and high-yield approach for the large-scale production of highly active Co/NCNTs catalyst transformed from zeolitic imidazolate frameworks (ZIFs). The precursor ZIF-67 could be easily prepared in an aqueous solution at room temperature in a short time (∼30 min) with a high space–time-yield. Followed by low-temperature (450 °C) pyrolysis, the Co/NCNTs catalyst was obtained in high yield. Benefiting from the high density and accessible active sites, Co/NCNTs-450 exhibits high activity in hydrogenation of aromatic hydrocarbon resin (AHCR) at 160 °C and 3 MPa (for the first time below 5 MPa), which was superior to the 5 wt% Pd/C. Furthermore, a combination of kinetic experiments and density functional theory (DFT) calculations were conducted to provide insight into the mechanism of AHCR hydrogenation. The 21 kinetic models based on the Eley-Rideal (ER) and Langmuir-Hinshelwood-Haugen-Watson (LHHW) formalism were proposed to describe the kinetic data obtained via elimination of the mass transfer limitations. On the basis of the model discrimination and regression results, the LHHW mechanism presented the best fit. And all the estimated kinetic parameters, including rate constants and activation energy, could be used in a reactor design for process scale-up. The DFT calculations further corroborated the kinetic modeling results that the surface reaction of chemisorbed AHCR and the dissociatively adsorbed hydrogen was the rate-determining step.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
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•Fuel potential of tackifying resins was studied by TG-FTIR and density functional theory analysis.•The calorific values of tackifying resins are 1.15–1.54 times of standard ...coal-equivalent.•R3 model is the best kinetic model by the isoconversional and master plots methods.•Resins studied had good fuel performance and combustion mechanism was proposed.
Combustion kinetics and fuel performance of tackifying resins such as glycerol ester of colophony (GEC), glycerol ester of hydrogenated colophony (GEHC), C9 petroleum resin (C9PR) and hydrogenated C9 petroleum resin (HC9PR) were studied. Non-isothermal thermal analysis was performed in an air atmosphere, and the combustion characteristic, kinetic and thermodynamic parameters were calculated. Results show that all the resins studied have good combustion performance and environmental characteristics, and their experimental calorific values are 1.15–1.54 times of standard coal-equivalent (29.31 MJ/kg), indicating that tackifying resins and their corresponding wastes are promising fuel for generating energy. Furthermore, based on the isoconversional and master plots methods, it was found that the combustion of different resins was a kinetically complicated reaction, but the R3 model had an acceptable fitting effect in the whole combustion process. TG-FTIR and density functional theory (DFT) results demonstrate that colophony-based resins tend to degrade/burn the branched chains first and then the tricyclic phenanthrene structures, while petroleum resins degrade/burn the CC bonds on the backbone first and then the aromatic compounds, and the volatiles are mainly composed of H2O, CH4, CO2, CO, aromatic compounds and carbonyl derivatives.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
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•An integrated in-situ/DIP (based on TWS)/ROIMI/BIV technique was employ to quantify hydrodynamic characteristics.•The hydrodynamic behaviors under DCPD-cyclohexane solutions were ...first reported.•The vortex clinging (VC) type cavities in the completely recirculated zone were first investigated.•A model of Acavity (R2 = 0.95) was proposed by 3 × 3 × 4 × 5 FFA approach.
Current research seeks to understand and optimize the aerated stirred tanks’ (ASTs) intensified transfer process by systematically investigating the relationship between gas cavities with hydrodynamic characteristics and operating conditions. A novel integrated in-situ/DIP (based on TWS Machine Learning)/BIV/ROIMI technique was demonstrated for effectively monitoring, identifying and quantifying hydrodynamic characteristics in complex multiphase mixing systems (1130 < Re < 17192). The CFD-PBM model with a Multiple-Reference-Frame approach was employed to simulate and verify experimental results. Experimental and simulated results showed that under vortex clinging (VC) cavity flow zone, with the area of cavity (Acavity) increasing, the bubble dispersion is better, Sauter diameter (de32) is smaller, holdup (εg) and interfacial area (a) are larger. When the Acavity is more than 150 mm2, the hydrodynamic characteristics are optimal. The significant factors for the formation of cavities were comprehensively analyzed via 180 sets of full-factorial analysis, namely, impeller types, rotation speed, solutions, rotation speed × impeller types, solutions × impeller types, flow rate × impeller types and rotation speed × flow rate. Furthermore, a model (R2 = 0.95) was proposed and successfully predicted Acavity (relative error less than 3 %). This work may provide valuable insights for optimizing the design and operating of ASTs for enhance multiphase mixing processes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
•Ni@C/g-C3N4 was fabricated by pyrolysis of the in-situ-formed Ni-MOF/g-C3N4 hybrid.•High-dense accessible active sites and mass transfer enhancement were realized.•Ni@C/g-C3N4 achieved 100 % ...dicyclopentadiene conversion at 1 bar and 30 ℃.•Norbornene ring prefers to adsorb and hydrogenate firstly on Ni@C/g-C3N4 catalyst.
The catalytic hydrogenation of dicyclopentadiene (DCPD) is one of the pivotal processes in the production of green high-energy-density liquid hydrocarbon fuels, jet propellent-10 (JP-10). However, the high dependency of the current catalysts on high temperature and pressure, whether the non-noble (>120 ℃, >15 bar) or even the noble catalyst (80 ℃, >7.6 bar), leads to enormous energy consumption and technical challenges in environment and sustainable development. Herein, we prepared a carbon layer wrapped Ni nanoparticles/g-C3N4 catalyst (Ni@C/g-C3N4) derived from the in-situ-formed Ni-MOF/g-C3N4 composite. Benefiting from the 53.2 wt% small-sized Ni nanoparticles and nanosheet structure, resulting in high-density accessible active sites (5.38 × 1020 sites g−1) and the mass transfer enhancement, Ni@C/g-C3N4 achieved DCPD hydrogenation under ambient conditions. > 99.9 % DCPD conversion and 98.1 % endo-tetrahydrodicyclopentadiene yield was obtained at 30 ℃, 1 bar, significantly outperforming the benchmark 5 % Pd/C. To the best of our knowledge, it’s the mildest condition for DCPD hydrogenation. Further, comprehensive mechanistic insights were gained from combining means of kinetic investigations, in situ characterization, and theoretical calculations. The discrimination result of 27 kinetic models indicated that DCPD hydrogenation followed the Langmuir-Hinshelwood-Haugen-Watson formulism regarding the reaction between the chemisorbed dihydrodicyclopentadiene (DHDCPD) and dissociatively adsorbed hydrogen as the rate-determining step. In-situ DRIFTS confirm that the norbornene ring is preferentially adsorbed and hydrogenated. The DFT calculations further substantiate the hydrogenation pathway. The present work provides guidance for the development of highly efficient non-noble metal catalysts and opens up an environmental-friendly and economically viable avenue for DCPD hydrogenation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Pyrolysis behavior of resins is essential for their high-temperature application. Herein, the high-temperature stability and pyrolysis kinetics and mechanism of rosin glyceride (RGE), hydrogenated ...rosin glyceride (HRGE), C9 petro-based resin (C9PR), and hydrogenated C9 petro-based resin (HC9PR) under a nonoxidizing atmosphere were investigated by thermogravimetry coupled with Fourier transform infrared spectrometry or mass spectrometry (TG–FTIR/MS) techniques. Friedman and Starink methods as well as reaction-order and truncated Sestak–Berggren models were used to evaluate kinetic and thermodynamic parameters, and results indicated that f(α) = (1 – α) n was the most probable pyrolysis mechanism for different resins. In addition, the average activation energies for pyrolysis of RGE, HRGE, C9PR, and HC9PR obtained by the Starink method were 188.97, 170.95, 159.69, and 151.66 kJ/mol, respectively, suggesting that bio-based resins exhibited better high-temperature stability than cycloaliphatic or aromatic petro-based resins thanks to their unique tricyclic phenanthrene structures, and the high-temperature stability of resins mildly would decrease after hydromodification due to the cracking of saturated bonds, which was well supported by TG–FTIR/MS analyses. Possible pyrolysis pathways were proposed.
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IJS, KILJ, NUK, PNG, UL, UM
In the present work, efficient catalytic hydrogenation of acrylic rosin (AR) were extensively investigated. Qualitative and quantitative analysis of AR and hydrogenated acrylic rosin (HAR) were ...carried out by GC and GC–MS, and the reaction pathway network about catalytic hydrogenation of AR was constructed. In addition, a Pd/C catalyst with well-dispersed ultrafine nano-palladium was prepared by impregnation method using Pd(NO
3
)
2
·2H
2
O precursor and put into use for the catalytic hydrogenation of AR. The structural properties of the catalyst were measured via XRD, TEM, ICP-OES, XPS, and BET. The characterizations showed that the ultrafine Pd nanoparticles (NPs) with an average Pd NPs size of 2.29 nm and consisting of 3.1% Pd were equably loaded on the surface of activated carbon. Benefiting from well-dispersed ultrafine Pd NPs, the catalyst exhibits outstanding activity in the hydrogenation of AR at 180 °C and 5 MPa, which shows 1.9 times superior activity than a commercial 10% Pd/C. The quality of prepared HAR is similar to the commercial HAR (Gardner color < 1, acid value of 235 mg KOH/g, softening point of 129 °C, 35% conversion rate of acrylpimaric acids).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The multi-factorial analysis was carried out for the alkylation reaction of isobutene/2-butene with response surface methodology (RSM), and a quadratic model was developed. The reaction conditions ...optimized by the quadratic model were obtained as follows: reaction time of 7 min, reaction temperature of 5 °C, and stirring speed of 1500 rpm. The relative error between the estimated value (76.72%) and the experimental value (77.47%) of the selectivity of TMPs was 0.98% under such reaction condition. The model well represents the correlation between the selectivity of TMPs with the reaction time, reaction temperature and stirring speed. The kinetic model for the alkylation reaction of isobutene/2-butene was developed according to the classical carbonium ion mechanism, where the catalyst was sulfuric acid. The kinetic parameters were fitted with nonlinear least squares to obtain reasonable rate constants and confidence intervals. The activation energies and pre-exponential factors calculated from the Arrhenius relationships, where the activation energy of the main reaction was 16.03 kJ/mol, and the activation energies of other side reactions ranged from − 62.59 to 59.94 kJ/mol.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
