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The effect of purified Cry1Ca insecticidal protein on the growth of Chlorella pyrenoidosa was studied in a three-generation toxicity test. The C. pyrenoidosa medium with a density of 5.4×105 cells/mL was subcultured for three generations with added Cry1Ca at 0, 10, 100, and 1000µg/L, and cell numbers were determined daily. To explore the distribution of Cry1Ca in C. pyrenoidosa and the culture medium, Cry1Ca was added at 1000µg/L to algae with a high density of 4.8×106 cells/mL, and Cry1Ca content was determined daily in C. pyrenoidosa and the culture medium by enzyme-linked immunosorbent assays. Our results showed that the growth curves of C. pyrenoidosa exposed to 10, 100, and 1000µg/L of Cry1Ca almost overlapped with that of the blank control, and there were no statistically significant differences among the four treatments from day 0 to day 7, regardless of generation. Moreover, the Cry1Ca content in the culture medium and in C. pyrenoidosa sharply decreased under exposure of 1000µg/L Cry1Ca with high initial C. pyrenoidosa cell density. The above results demonstrate that Cry1Ca in water can be rapidly adsorbed and degraded by C. pyrenoidosa, but it has no suppressive or stimulative effect on algae growth. [Copyright &y& Elsevier]

Gene therapy and antibody approaches are crucial auxiliary strategies for hepatocellular carcinoma (HCC) treatment. Previously, we established a survivin promoter‐regulated oncolytic adenovirus that has inhibitory effect on HCC growth. The human sulfatase‐1 (hSulf‐1) gene can suppress the growth factor signaling pathways, then inhibit the proliferation of cancer cells and enhance cellular sensitivity to radiotherapy and chemotherapy. I131‐metuximab (I131‐mab) is a monoclonal anti‐HCC antibody that conjugated to I131 and specifically recognizes the HAb18G/CD147 antigen on HCC cells. To integrate the oncolytic adenovirus‐based gene therapy and the I131‐mab‐based radioimmunotherapy, this study combined the CArG element of early growth response‐l (Egr‐l) gene with the survivin promoter to construct a radiation‐inducible enhanced promoter, which was used to recombine a radiation‐inducible oncolytic adenovirus as hSulf‐1 gene vector. When I131‐mab was incorporated into the treatment regimen, not only could the antibody produce radioimmunotherapeutic effect, but the I131 radiation was able to further boost adenoviral proliferation. We demonstrated that the CArG‐enhanced survivin promoter markedly improved the proliferative activity of the oncolytic adenovirus in HCC cells, thereby augmenting hSulf‐1 expression and inducing cancer cell apoptosis. This novel strategy that involved multiple, synergistic mechanisms, including oncolytic therapy, gene therapy and radioimmunotherapy, was demonstrated to exert an excellent anti‐cancer outcome, which will be a promising approach in HCC treatment. Highlights: ► A radiation‐induced oncolytic adenovirus is constructed as hSulf‐1 gene vector.► I131‐metuximab boosts oncolytic adenoviral proliferation in hepatocellular carcinoma.► I131‐metuximab increases adenovirus‐mediated hSulf‐1 expression in cancer cells.► Oncolytic adenovirus and I131‐metuximab synergistically increase antitumor effect. [ABSTRACT FROM AUTHOR]

Replication-competent adenovirus ( RCAd) has been used extensively in cancer gene therapy, and tumor-selection is critical for the use of replication-competent adenovirus. Here we investigated the anti-tumor characterization of oncolytic virus, whose E1 A gene is under the control of a renal cell carcinoma specific promoter - the G250 promoter. The constructed oncolytic virus G250- Ki67 is armed with transgene of Ki67-si RNA, and G250- ZD55- Ki67 also with E1 B-55 KD deleted. The tumor-specific expression of E1 A and Ki67 was demonstrated by Western blot and immunohistochemistry staining, and the tumor-specific cytotoxicity was assessed by crystal violet staining and cell viability assays. The G250- Ki67 and G250- ZD55- Ki67 adenoviruses could express E1 A protein in 786- O and OSRC cell lines but not in ACHN and HK-2 cell lines. The expression of Ki67 gene in 786- O and OSRC cell lines were suppressed by these adenoviruses. The cytotoxic effects induced by G250- ZD55- Ki67 and G250- Ki67 were more obvious on the 786- O cell lines than on the OSRC cell lines. Each group of adenoviruses could inhibit the proliferation of the 786- O cells and OSRC cells. However, the effects induced by G250- ZD55- Ki67 and G250- Ki67 on 786- O cells were stronger than on OSRC cells. Moreover, G250- ZD55- Ki67 had enhanced antitumor activities in these renal cancer cells compared with G250- Ki67. G250 promoter-derived CRAds carrying Ki67-si RNA could highly amplify and express Ki67-si RNA in renal cancer cells with expression of G250 antigen, inhibit renal cancer cells proliferation and induce apoptosis. These results demonstrated that the G250-specific oncolytic adenovirus expressing Ki67-si RNA is applicable for human renal clear cell cancer therapy. [ABSTRACT FROM AUTHOR]

Data from clinical trails have shown that the antitumoral effect of ONYX-015, an E1B 55kDa-deficient adenovirus, as monotherapy is insufficient. To enhance its efficiency, CNHK200-mE, another E1B 55kDa-deficient adenovirus armed with a mouse endostatin gene was constructed and its antitumoral activities against hepatocellular carcinoma (HCC) in vitro and in vivo were investigated. The selective replication and cytotoxicity of CNHK200-mE in Hep3B and HepGII cells independent of p53 status were confirmed via TCID50 and 3-(4,5dimetylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assays. Potent tumor growth suppression on SMMC-7721 xenografts in nude mice was observed and a synergistic effect of the carrier virus and the therapeutic gene was suggested. Moreover, in comparison with the nonreplicative adenovirus carrying the same therapeutic gene, amplified transgene expression of mouse endostatin in vitro and in vivo were confirmed by Western blotting and ELISA assay. The effective angiogenesis inhibition and replication of CNHK200-mE in nude mice xenografts were demonstrated by immunohistochemistry. In conclusion, the recombinant adenovirus CNHK200-mE is a replication-competent oncolytic virus mediating high expression of therapeutic gene. Because CNHK200-mE is capable of replicating in and lysing HCC cells selectively with effective tumor growth suppression and antiangiogenic activity on HCC xenografts in nude mice, it holds good potential for the treatment of HCC. [ABSTRACT FROM AUTHOR]

• Rich oxygen and nitrogen doped porous carbons were prepared for CO 2 capture. • The contribution of pore structure and functional groups is roughly 62% and 38%, respectively. • Nitrogen and oxygen functional groups exerts a great influence on the CO 2 /N 2 selectivity. • The study explains the role of functional groups and pore structure on CO 2 capture and separation. The heteroatom-doped porous carbon is an effective strategy to improve the CO 2 uptake. However, there are obvious contradictory conclusions in the previous reports regarding the influences of nitrogen groups and pore sizes. Besides this, previous researches about CO 2 capture and CO 2 /N 2 selectivity on nitrogen-doped carbon materials often ignore the effect of oxygen-containing functional groups. Herein, we successfully synthesized rich oxygen and nitrogen doped carbon materials by hydrothermal treatment using tobacco stem and ethylenediamine, respectively. The obtained porous carbons exhibit high surface area (906–2940 m2 g−1). From the experimental results, at 1 bar, NC600 exhibits the superior CO 2 adsorption of 4.33 mmol g−1 and 6.54 mmol g−1 at 25 °C and 0 °C, respectively. Based on GCMC simulation, we can roughly estimate that the contribution of pore structure and functional groups is 62% and 38%, respectively. Nitrogen and oxygen-doped porous carbons exerts a greater influence on the CO 2 /N 2 selectivity because of the electrostatic interactions enhancement between carbon surface and CO 2 molecules. The study is expected to better understand the role of functional groups and pore structure on CO 2 capture and CO 2 /N 2 selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A petroleum coke-based porous carbon with ultrahigh efficiency was synthesized. • The graphitized mesopore-micropore channels were constructed. • The structure of graphitized mesopore-micropore channel was observed. • The PSA performances of PC-10 were improved by 20 %. • The co-effect of E d and mesopore-micropore channels was analyzed. Benzene is a harmful VOC, which usually form a certain concentration of gas. The transport of benzene molecules in the pore structure is the key to benzene gas treatment. Here we report an effective synthesis of petroleum coke-based porous carbon with ultrahigh efficiency benzene molecular transport channels. These mesopore-micropore channels can effectively improve the transport of benzene molecules in the interior of pore structure, and the graphitization also enhances the adsorption for benzene. The results shows that the adsorption efficiency of PC-10 with the graphitized mesopore-micropore channels reaches 90.22 %, which is 22.47 % higher than that of PC-0. Moreover, the complete structure of graphitized mesopore-micropore channel was observed, which is constituted of mesoporous channel, branch structure, cavity structure, microporous channel, and graphitized interior surface. Compared with microporous carbon in PSA, the breakthrough time of PC-10 is extended by 22 % and the effective amount is saved by 25 %. Due to the co-effect of low desorption activation energy and micropore-mesopore channels, the enrichment ratio of PC-10 reaches 3.46 in PD step, which is 21 % higher than that of microporous material. Our study provided an effective strategy for the synthesis of porous materials, and developed its application on PSA for benzene. [ABSTRACT FROM AUTHOR]

Porous carbon materials doped with nitrogen (N) and phosphorous (P) were synthesized by the chemical activation method to study their performance in the acetone adsorption at ambient temperature. Especially, the sample activated at 800 °C had the highest acetone capacity of 945.3 mg g−1, which was well fitted by the Langmuir (L) and Langmuir-Freundlich (L-F) models. The physico-chemical characterizations and DFT calculations indicated its high dispersion of adsorption sites and accessibility of acetone to adsorption sites: large specific surface area (2762.0 m2 g−1), uniform dispersion of micropores (1.096 cm3 g−1), and good adsorption affinity with acetone by pyrrolic-N (−0.35759 eV) and C–P–O (−0.50277 eV) functional groups. Considering this, we concluded that the acetone adsorption was dominated by the surface physical structure (specific surface area and microporocity) while N and P surface functional groups played a second role in the adsorption enhancement effect. Image 1 • Nitrogen and phosphorous co-doped porous carbon composites were synthesized. • Acetone adsorption was dominated by specific surface area and microporocity. • Surface functional groups played a secondary important role in the acetone adsorption. • Adsorption mechanism of acetone and NP composites was clarified by experimental and DFT methods. [ABSTRACT FROM AUTHOR]

• Nitrogen doped carbon materials with hierarchical porous structure and ultrahigh S BET were prepared. • N-functional groups provided a stronger polarity for adsorbent and enhanced the adsorption of VOCs. • The Langmuir-Freundlich model was found to fit quite well with the adsorption equilibrium data. • Adsorption mechanism of VOCs was clarified by experimental and DFT methods. The objective of this study was to assess the VOCs (methanol and toluene) adsorption capacity of doped porous carbon materials (resin-based carbon and bamboo char) by experiments and theoretical calculations. Results showed N-doped porous carbon material exhibited a high specific area (2293.2 m2 g−1), a desirable microporocity (0.90 cm3 g−1), and a large adsorption capacity for methanol (915.3 mg g−1) and toluene (622.9 mg g−1), which were better than those derived from bamboo char. According to the density functional theory calculation, in terms of different N-containing functional groups, the results showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol, while toluene was mainly trapped through π-π dispersive interaction with the aromatic ring moving to the carbon surface. This study gave us hints to conduct the doping of polarized element to adsorb polar gases. [ABSTRACT FROM AUTHOR]

• Removal of indoor HCHO could be enhanced by doping optimized elements. • The static/dynamic adsorption trends of doped materials to HCHO were consistent. • The adsorption energy of doped carbon materials to HCHO was P > S > N by DFT calculations. • Surface functional groups played a secondary important role in the HCHO adsorption. The objectives of this study were to assess the formaldehyde (HCHO) adsorption capacity of doped porous carbon by experiments and theoretical calculations. Nitrogen, sulfur or phosphorus containing porous carbons were prepared with different precursors by activation with KOH at 700 °C and compared with commercial activated carbon (CAC), and used as the low HCHO concentration adsorbents in dry (dynamic) and wet (static) conditions. Results showed that the HCHO adsorption capacity of AC-N (2418.20 m2 g−1) for dynamic (13.60 mg g−1) and static (1.43 mg g−1) was greater than that of AC-S, CAC and AC-P. The specific surface area and the micropores volume were expected to markedly influence the adsorption capacity of HCHO. According to the DFT calculation, the adsorption energy of surface functional groups of phosphorus (−0.53296 eV) was the highest, followed by sulfur (−0.52646 eV) and nitrogen (−0.41246 eV), which indicated hydrogen bond interaction played an important role in the adsorption. In the GCMC slit model, the size of slit pores was positively correlated with the adsorption amount of HCHO. With the increase of the adsorption pressure, the surface functional groups had little effect on the adsorption of HCHO under the same size of the slit pores. Accordingly, for the high HCHO adsorption capacity, specific surface area and pore volume are the primary determinant, while surface functional group is the secondary determinant. This would provide a useful theoretical reference for the doping of polarized activated carbon to adsorb polar gases. [ABSTRACT FROM AUTHOR]

The method of combining test and simulation was adopted to explore the failure process and load distribution of the structure under axial compression load. The failure mode of the inclined sandwich structure was investigated by experiments. Hashin criterion and cohesive force element were introduced to establish finite element analysis model for damage simulation. The results showed that the root edge was the maximum stress area of the sandwich structure. The initial damage appeared in the bonding layer at the sharp corner of the root, and gradually expanded at the adhesion between the bottom panel and the foam, resulting in the stiffness of the lower panel plummeting and breaking. [ABSTRACT FROM AUTHOR]

[Display omitted] • A kind of activated carbon with alterable phosphorus functional groups and stable structure was synthesized. • The chemical functional groups influence coefficient (A C) was proposed. • The performance of TSA and PSA can be predicted by the chemical functional groups influence coefficient (A C) accurately. • The factors affecting curve characteristics in TSA and PSA and their mechanisms were revealed respectively. • The main factors causing the attenuation of activated carbon in TSA and PSA were revealed respectively. Volatile organic compounds (VOCs) emissions cause serious health problems and environmental pollution, and modified activated carbon is widely used in the treatment of VOCs pollution. Methanol was selected as adsorbate and activated carbon with alterable phosphorus functional groups was synthesized as adsorbent. In the absence of the influence of the physical properties, the chemical functional groups influence coefficient (A C) was proposed, which can be used to analysis and predict the influence of chemical functional groups specially. The results show that the performances including adsorption capacity and enrichment ratio are positively related to the A C whether in temperature swing adsorption (TSA) or pressure swing adsorption (PSA). By comparison, the adsorption capacity of PSA is greater than that of TSA because of the higher efficiency caused by faster cycle. Further research on process showed that the curve character of TSA, including breakthrough time and equilibrium time, is highly related with A C , but the curve character of PSA is mainly depended on the state of activated carbon. Therefore, the attenuation of TSA is mainly caused by the change of chemical functional groups, while the attenuation of PSA is mainly caused by the failure of activated carbon. [ABSTRACT FROM AUTHOR]

Ball bearings play a pivotal role in rotating machinery, making it crucial to detect their wear condition in real time for preventive maintenance. This paper proposes a novel method, involving one-dimensional convolutional neural network (1DCNN) and lubricating oil, which is sensitive to early abnormal wear, to intelligently predict the wear condition of ball bearings. To achieve that, an industrial-level gas turbine is used in the test to simulate the practical working conditions. During the machine's operation, the lubricating oil is sampled at different time intervals for spectral oil analysis (SOA), which is later utilized as the input data set. The 1DCNN model is then constructed and fine-tuned to extract its wear characters, and finally outputs a one-dimensional time-sequence feature vector of the SOA data, providing wear information for the upcoming hours. The predicted results have shown that the 1DCNN model can effectively predict the trend of wear condition with higher accuracy of over 97% and better generalization performance compared with the BP neural networks. Additionally, the validation test results have also verified the reliability of the 1DCNN model, which can be useful for manufacturing industries in reducing costly maintenance fees by early detection of potential failure. [ABSTRACT FROM AUTHOR]

The ingression of external contaminants probably causes spalling even severe failure, which may have significant effects on operation reliability of gas turbines. To investigate the evolution and determine the mechanism, artificial pits were made on the outer bearing ring raceway to simulate such failure. Comprehensive investigation into the base materials, macro and micro surface morphologies, service environments including lubricating oil analysis were conducted after disassembly of the engine. Also, during the 3-hours' operation, vibration and the metal debris monitoring were implemented. Results of this paper have demonstrated that the rolling contact fatigue spalling initiated from the edge of the dent with a distance of approximately 100 millimeters and extended along the balls' movement trace in the load-carrying area, while in the non-load-carrying area, no visible wear traces were found. The vibration and the metal debris analysis have demonstrated that the protruded edge was formed due to metal accretion around the dent, which later lead to stress concentrations, and it disappeared in the load-carrying area and induced spalling. This paper has discovered the initial failure morphologies and original site of contact fatigue spalling of ball bearings, and specified the mechanism through the simulation caused by foreign substance. [ABSTRACT FROM AUTHOR]

In this paper, a mean-field homogenization based approach implemented in the two steps sequentially is proposed to evaluate the macroscopic coefficients of thermal expansion (CTEs) of multi-phase composites. The adopted mean-field homogenization models are the quadratic interpolative M-T/D-I mean-field homogenization model in the first-step homogenization procedure and the simple interpolative Voigt/Reuss mean-field homogenization model in the second-step homogenization procedure, respectively. The proposed mean-field homogenization based approach is validated by comparing with the RVE based FE homogenization method. The simulation results indicate that with the increase of the inclusion volume fraction, the macroscopic CTEs of multi-phase composites generally decrease because that the inclusions possess the smaller CTEs than the matrices. However, in the case of multi-phase composites with the planarly distributed inclusions, the through-thickness CTEs firstly increase with the increase of the inclusion volume fraction and then decrease with the increase of the inclusion volume fraction. The effect of the inclusion aspect ratio on the macroscopic CTEs of multi-phase composites can be neglected, while the effect of the inclusion transversely isotropic material properties on the macroscopic CTEs of multi-phase composites must be considered. [ABSTRACT FROM AUTHOR]

To investigate the effect of fiber orientation on the effective elastic properties of short-fiber-reinforced metal matrix composites, the two-step mean-field homogenization procedures including the D-I/Reuss, M-T/Reuss, D-I/Reuss, M-T/Voigt and D-M/V-R models are introduced and the corresponding numerical implementations are detailed. Compared with the RVE based FE homogenization method, the two-step mean-field homogenization procedures: D-I/Reuss, M-T/Reuss, D-I/Reuss, M-T/Voigt and D-M/V-R models to predict the effective elastic properties of short-fiber-reinforced metal matrix composites are validated. The simulation results show that the effective elastic moduli E 22 and E 33 of short-fiber-reinforced metal matrix composites with the aligned fibers reach the minimums around θ = 60 ° and 30 ° , respectively, but not 90 ° or 0 ° , while the effective shear modulus G 23 reaches a maximum at θ = 45 ° and shows a symmetrical distribution. For short-fiber reinforced metal matrix composites with the planarly randomly distributed fibers, the effective elastic moduli E 22 and E 33 are close to those of short-fiber reinforced metal matrix composites with the aligned fibers presenting the orientation angle θ of 35 ° and 55 ° , respectively, but not 45 ° , while the effective shear modulus G 23 is close to those of short-fiber reinforced metal matrix composites reinforced by the aligned fibers with the orientation angles of both 20 ° and 70 ° . [ABSTRACT FROM AUTHOR]

The effective thermal conductivity of metal matrix composites (MMCs) reinforced by the randomly distributed transversely isotropic fibers is evaluated using the representative volume element (RVE) based finite element (FE) homogenization method. The modified random sequential absorption (RSA) algorithm is proposed to generate the periodic RVEs of MMCs and thus the periodic boundary conditions are introduced. The transversely isotropic thermal conductivity of fiber is considered and its numerical implementation in the FE analysis is detailed. The RVE based FE homogenization method to predict the effective thermal conductivity of MMCs reinforced by the randomly distributed fibers is verified by comparing against the experiment and the Hashin–Shtrikman bounds. The simulation results show that the effect of the transverse isotropy of fiber thermal conductivity on the effective thermal conductivity of MMCs reinforced by the randomly distributed fibers can be neglected owing to the large matrix/fiber thermal conductivity ratio. The effective thermal conductivity of MMCs reinforced by the randomly distributed fibers decreases with the increase of fiber volume fraction, while the effect of fiber aspect ratio on the effective thermal conductivity of MMCs reinforced by the randomly distributed fibers is not significant. [ABSTRACT FROM AUTHOR]

In this paper, the two-step mean-field homogenization procedures including the Mori–Tanaka (M–T) and interpolative double inclusion (D-I) models in the first-step homogenization procedure and the Voigt and Reuss models in the second-step homogenization procedure, are introduced and implemented to predict the effective elastic properties of short-fiber-reinforced metal matrix composites. To take into account the effect of fiber orientation, the detailed implementation of the fiber orientation transformation and fiber orientation averaging procedure is described. Compared with the effective elastic properties of short-fiber-reinforced metal matrix composites predicted by the RVE based FE homogenization method and measured from the uniaxial tensile experiments, the two-step mean-field homogenization procedures: D-I/Reuss, M–T/Reuss, D-I/Voigt and M–T/Voigt would provide the acceptable predictions on the effective elastic properties of short-fiber-reinforced metal matrix composites, and the D-I/Reuss and M–T/Voigt two-step mean-field homogenization procedures provide more tight bounds (D-I/Reuss as the lower bound and M–T/Vogit as the upper bound). For more accurate estimate of the effective elastic properties of short-fiber-reinforced metal matrix composites, a modified two-step mean-field homogenization procedure is proposed and validated. [ABSTRACT FROM AUTHOR]

Winged aphids develop more sensitive olfaction than the wingless phenotype to identify potential habitat from afar. Two types of olfactory sensilla, primary rhinarium (PRh) and secondary rhinarium (SRh) are responsible for aphid olfactory perception, of which, SRh is involved in the perception of both E -β-farnesene (EBF) and plant volatiles. Odorant binding proteins (OBPs) play a vital role in the response of insect olfactory nerves located in the rhinarium to external odor stimuli. However, the role of SRhs in winged aphids have received little attention to date and the underlying mechanisms of how OBPs work for the olfactory enhancement in winged aphids are unclear. Here, we compared and analyzed the number of SRhs on the antennae of winged and wingless aphids in the grain aphid Sitobion miscanthi , then highly expressed OBPs in antennae of winged aphids were screened based on both transcriptomic and proteomic data and identified by parallel reaction monitoring parallel reaction monitoring (PRM). Furthermore, the affinity of highly expressed OBPs was tested. The results showed that winged aphids have more SRhs, and the three highly expressed OBPs, SmisOBP6/7/10, in winged antennae shared broad and overlapped ligands spectra with plant volatiles and pheromones. Furthermore, OBP9, as an OBP with high expression in antennae, not only binds EBF, but also shows extensive affinity to various ligand types. Our results highlight the importance of the higher number of SRhs as the morphological basis of enhanced olfactory perception in winged aphid and further indicates the involvement of OBP6/7/10 as the molecular support of this process. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of surface functional groups for H 2 purification were elucidated. • The separation property of H 2 over impurity gases was investigated. • The competitive adsorption effect was analyzed through two hypothetical paths. • Guild to design novel porous carbon materials for H 2 purification. Efficiently and selectively purifying hydrogen from multi-component gas mixtures has emerged as a pivotal aspect in the hydrogen economy. Herein, the separation properties and mechanistic effects of porous carbons for rich hydrogen mixtures were investigated. It focused on the competitive adsorption behavior of H 2 over N 2 , CO 2 and CH 4 in surface-functionalized graphene models (G-Rs, R = C O, NH 2 , SO 3 H, (CO)C 2 PO), and explored its separation mechanism at a microscopic level. The results showed that for surface functional groups, G-Rs exhibit a superior H 2 separation performance than G-None (pristine graphene model) due to the stronger electrostatics interaction. Specially, G-(CO)C 2 PO exhibited the highest N 2 /H 2 , CO 2 /H 2 and CH 4 /H 2 adsorption selectivity of 7.3, 1179.4 and 53.4, respectively, which was an enhancement of 73 %, 615 % and 383 % than that of G-None. In addition, the competitive adsorption effect was analyzed through two hypothetical paths for the adsorption process of CO 2 /H 2 gas mixture on porous carbons. To be specific, the H 2 and CO 2 molecules would occupy the different active adsorption sites due to the various weak interactions between gas molecules and adsorption surfaces, resulting in the different adsorption behaviors. Furthermore, the intrinsic mechanism of H 2 separation property on porous carbon was also evaluated by scanning the potential energy surface and analyzing the charge density difference. This work provides a novel insight into the strategy of designing promising porous carbons for effective H 2 purification and recovery. [ABSTRACT FROM AUTHOR]

• Mechanical compaction treatment can directionally increase the volume of ultramicropores. • Nitrogen doping treatment reduces the pore volume of ultramicropores. • Ultramicropore smaller than 0.5 nm determine CO 2 capture at 0.15 bar and CO 2 /N 2 selectivity. • Explained the influence of pore structure and functional groups on CO 2 capture and separation. In the preparation of biomass-derived porous carbon, targeting the enhancement of ultramicropore volume and understanding the effects of nitrogen doping on ultramicroporous structure are crucial for improving CO 2 capture. Here, we prepared porous carbon using mechanical compaction and urea-assisted KOH activation of tobacco stem-derived hydrochar. The results showed that mechanical compaction increased the ultramicropore volume with little impact on oxygen content, leading to an increase in CO 2 adsorption capacity, with a maximum adsorption capacity of 5.6mmol g−1 at 25℃ and 1 bar. In contrast, nitrogen doping negatively affected the ultramicropore structure and oxygen functionalities, resulting in a decrease in CO 2 adsorption capacity. Furthermore, experimental and molecular simulation studies revealed that ultramicropore smaller than 0.5 nm predominantly determine the CO 2 adsorption capacity at 0.15 bar and CO 2 /N 2 selectivity. These findings provide theoretical and practical support for the development of efficient carbon-based CO 2 adsorbents. [ABSTRACT FROM AUTHOR]

Porous carbon is an ideal adsorbent for the elimination of volatile organic compounds (VOCs) attributed to their price, availability and excellent adsorption capacity. However, there are significant variation in the adsorption capacity and adsorption selectivity of different precursors for VOCs under humid conditions after modification because of the differences in their own structural properties. In this study, graphitized hydrophobic porous carbon with excellent specific surface area was successfully synthesized by selecting bamboo fiber, maize, coconut husk and coal as precursors and potassium hydroxide as an activator. Among them, the dynamic adsorption capacity of benzene in the sample with bamboo fiber as precursor was maintained at 74.7 % under the high humidity condition (RH90 %) compared with the dry state (RH0 %). Grand Canonical Monte Carlo (GCMC) simulations and weak interaction force analyses showed that enhanced dispersion attraction between graphitized carbon surfaces and benzene molecules in comparison to disordered carbon surfaces. The existence of oxygen functional groups enhanced the interaction between porous carbon and water through hydrogen bonding leading to preferential adsorption of water molecules, which resulting in the decrease of their adsorption performance in wet condition. This research provided theoretical and experimental views of the effects of graphitization and oxygen functional groups on the competitive adsorption capture of benzene and water by porous carbon, which further provided a reliable approach to synthesizing porous carbon with high adsorption capture for benzene removal in high humidity environments. [Display omitted] • Screening for efficient activation and graphitization of the precursors for porous carbon. • Excellent benzene adsorption retention (74.7 %) in humid environments (RH90 %). • Benzene adsorption selectivity affected by graphitization and oxygen content. • Enhanced dispersion facilitates the adsorption selectivity of benzene on sp2 carbon. • Hydrogen bonding impairs the adsorption selectivity of benzene and water. [ABSTRACT FROM AUTHOR]