Small GTP-binding proteins function as regulators of specific intercellular fundamental biological processes. In this study, a small GTP-binding protein Rab7 gene, designated as TaRab7, was ...identified and characterized from a cDNA library of wheat leaves infected with Puccinia striiformis f. sp. tritici (Pst) the wheat stripe rust pathogen. The gene was predicted to encode a protein of 206 amino acids, with a molecular mass of 23.13 KDa and an isoeletric point (pI) of 5.13. Further analysis revealed the presence of a conserved signature that is characteristic of Rab7, and phylogenetic analysis demonstrated that TaRab7 has the highest similarity to a small GTP binding protein gene (BdRab7-like) from Brachypodium distachyon. Quantitative real-time PCR assays revealed that the expression of TaRab7 was higher in the early stage of the incompatible interactions between wheat and Pst than in the compatible interaction, and the transcription level of TaRab7 was also highly induced by environmental stress stimuli. Furthermore, knocking down TaRab7 expression by virus induced gene silencing enhanced the susceptibility of wheat cv. Suwon 11 to an avirulent race CYR23. These results imply that TaRab7 plays an important role in the early stage of wheat-stripe rust fungus interaction and in stress tolerance.
The safety of lithium-ion batteries (LIBs) has always been a research hotspot in the field of new energy. Herein, F-TiO2/PMIA composite separator with thermotolerance and mechanical robustness is ...designed and fabricated by directed-assembly with strong hydrogen bonding between the poly (m-phenylene isophthalamide) (PMIA) and fluorine functionalized porous titanium dioxide (F-TiO2). The results show that F-TiO2/PMIA composite separator exhibits excellent mechanical properties with tensile strength of 24.6 MPa. The elongation at break is 45.6%, which is increased by 591% compared with PMIA separator (6.6%), closing to Celgard PP separator (48.5%). At the same time, the F-TiO2/PMIA composite separator possesses flame resistance and self-extinguishing properties. Moreover, does not shrinkage under the heating conditions of 250 °C, which greatly improves the safety of LIBs. In terms of electrochemical performance, F-TiO2/PMIA composite separator has the highest ionic conductivity (1.30 mS cm−1) and delivers a high initial discharge capacity of 146.6 mAh g − 1 and a discharge capacity of 134.3 mAh g − 1 after 50 cycles at 0.2 C, with capacity of 90.1 mAh g − 1 at 2 C. Therefore, the novel F-TiO2/PMIA composite separator offers promising commercial prospects in future high-safety and high-performance energy applications.
Pall has a long history of being used as a traditional medicine to treat hypertension, headache, insomnia, constipation and vertigo. However, only a few biologically active substances have been ...identified from
. Here, the shoots and roots of
, namely L-Sc and R-Sc, were studied. The primary and secondary metabolites were investigated using ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS). A total of 637 putative metabolites were identified and these metabolites were mainly classified into ten different categories. Correlation analysis, hierarchical clustering analysis, principal component analysis and orthogonal partial least squares discriminant analysis of metabolites showed that the L-Sc samples could be clearly separated from the R-Sc samples. Differential accumulated metabolite analysis revealed that most of differential primary metabolites were significantly lower in the L-Sc than in the R-Sc. Conversely, the major differential secondary metabolites had higher levels in the L-Sc than in the R-Sc. Further analysis indicated that the flavonoids were the major putative antioxidant components and most of putative antioxidant components exhibited higher relative concentrations in the L-Sc than the R-Sc. These results improve our understanding of metabolite accumulation and provide a reference for the study of medicinal value in
.
Novel polymers applied in economic membrane technologies are a perennial hot topic in the fields of natural gas purification and O
enrichment. Herein, novel hypercrosslinked polymers (HCPs) ...incorporating 6FDA-based polyimide (PI) MMMs were prepared via a casting method for enhancing transport of different gases (CO
, CH
, O
, and N
). Intact HCPs/PI MMMs could be obtained due to good compatibility between the HCPs and PI. Pure gas permeation experiments showed that compared with pure PI film, the addition of HCPs effectively promotes gas transport, increases gas permeability, and maintains ideal selectivity. The permeabilities of HCPs/PI MMMs toward CO
and O
were as high as 105.85 Barrer and 24.03 Barrer, respectively, and the ideal selectivities of CO
/CH
and O
/N
were 15.67 and 3.00, respectively. Molecular simulations further verified that adding HCPs was beneficial to gas transport. Thus, HCPs have potential utility in fabrication of MMMs for facilitating gas transport in the fields of natural gas purification and O
enrichment.
A TiO
2
/PMIA composite separator was prepared using poly(m-phenylene isophthalamide) (PMIA) as the base separator and polyacrylonitrile (PAN) as the binder to load TiO
2
particles on its surface. ...The tensile strength of the TiO
2
/PMIA composite separator (37 MPa) was found to be greater than that of the pure PMIA separator (22 MPa) (increment of 68.2%), whereas the elongation at break of the TiO
2
/PMIA composite separator increased by 40%. TiO
2
is a semiconductor material with a high dielectric constant which is also beneficial to improve electrochemical performance of PMIA seperator. The button cell assembled by the TiO
2
/PMIA composite separator had the best cycle performance (113.6 mAh/g), and its specific capacity was still 85.5 mAh/g at 2 C. Therefore, TiO
2
/PMIA composite separators with high mechanical properties can be used as promising lithium-ion battery separators in a wide range of applications.
The fabrication of novel separators with high safety and remarkable performance has always been a hot topic due to their effect on the safety and electrochemical performance of lithium-ion batteries ...(LIBs). In this study, the impregnation method is used to create the 4, 4′-diphenylmethane diisocyanate (MDI) modified poly (m-phenylene isophthalamide) (PMIA) separators (PMIA-M) with 3-D sponge-like porous network structure. With the increase of cross-linking time, the elongation at break of PMIA-M separators increases to 47.2%, and the mechanical strength decreases after increasing to 31.7 MPa. In addition, PMIA-M separators has excellent thermal stability, no dimensional shrinkage at 200 °C and self-extinguishing property. Moreover, the expansion of polar groups improves the surface polarity of the PMIA-M separators, promoting the electrolyte-philic property and leading to a significant increase in electrochemical performance. Transport channels of Li+ can be regulated, so that the growth of lithium dendrites can be inhibited and the cycle stability is significantly improved. The capacity retention of the LiCoO2/Li cell assembled by the PMIA-M-12 separator is 94.7% after 50 cycles at 0.2C and prior to that of the pristine PMIA separator (77.6%). Therefore, the PMIA-M separators are promising material for electronic products and new energy vehicles.
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•3-D sponge-like porous PMIA-M separators were fabricated.•PMIA-M separators has good mechanical properties and self-quenching performance.•PMIA-M separators can inhibit the formation of Li dendrite.•PMIA-M separators can have an promising application in LIBs.
The chemical complexation on the solid/liquid interface of PF6- in the electrolyte and Cr3+ in the MIL-101 framework promotes Li+ transport, thus enhancing the electrochemical performance of the ...lithium-ion batteries. In addition, MIL-101 enhances the thermal stability of the PMIA separator and improves the safety of the lithium-ion batteries.
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•MIL-101 was successfully embedded in pore channels of the PMIA separators by a facile casting process.•The PMIA/MIL-101 composite separators possess resistant-folding property, contact angle about 16.9° and has no obvious shrinkage at 200 °C.•The PMIA/MIL-101 composite separators facilitate Li+ transference thanks to chemical complexation between PF6- and Cr3+ on the solid/liquid interface.•tLi+ of the PMIA/MIL-101 composite separators is 261% higher than that of the PMIA separators.•Compared with commercial PP separators and pristine PMIA separators, the PMIA/MIL-101 composite separators have outstanding safety and electrochemical performance.
Energy storage devices require separators with sufficient lithium-ion transfer and restrained lithium dendrite growth. Herein, PMIA separators tuned using MIL-101(Cr) (PMIA/MIL-101) were designed and fabricated by a one-step casting process. At 150 °C, the Cr3+ in the MIL-101(Cr) framework sheds two water molecules to form an active metal site that complexes with PF6- in the electrolyte on the solid/liquid interface, leading to improved Li+ transport. The Li+ transference number of the PMIA/MIL-101 composite separator was found to be 0.65, which is about 3 times higher than that of the pure PMIA separator (0.23). Additionally, MIL-101(Cr) can modulate the pore size and porosity of the PMIA separator, while its porous structure also functions as additional storage space for the electrolyte, enhancing the electrochemical performance of the PMIA separator. After 50 charge/discharge cycles, batteries assembled using the PMIA/MIL-101 composite separator and the PMIA separator presented a discharge specific capacity of 120.4 and 108.6 mAh/g, respectively. The battery assembled using PMIA/MIL-101 composite separator significantly outperformed both the batteries assembled from pure PMIA and commercial PP separators in terms of cycling performance at 2 C, displaying a discharge specific capacity of 1.5 times that of the battery assembled from PP separators. The chemical complexation of Cr3+ and PF6- plays a critical role to improve the electrochemical performance of the PMIA/MIL-101 composite separator. The tunability and enhanced properties of the PMIA/MIL-101 composite separator make it a promising candidate for use in energy storage devices.
Imino hypercrosslinked polymers (NH‐HCPs), amino hypercrosslinked polymers (NH2‐HCPs), and carboxyl hypercrosslinked polymers (COOH‐HCPs) were synthesized through cross‐linking and Friedel‐Crafts ...reactions to serve as highly efficient adsorbents for doxycycline hydrochloride (DOX) in water. These polymers, NH‐HCPs, NH2‐HCPs, and COOH‐HCPs, exhibited specific surface areas measuring 450, 267.576, and 94.39 m2/g, respectively. The adsorption kinetics of DOX onto these polymers were consistent with the pseudo‐second‐order model, while the adsorption isotherms followed the Langmuir model (NH‐HCPs) and Freundlich model (NH2‐HCPs and COOH‐HCPs), respectively. The maximum DOX adsorption capacities for NH‐HCPs, NH2‐HCPs, and COOH‐HCPs were 166.82, 132.43, and 72.07 mg/g, respectively. Simulation results indicated that COOH‐HCPs exhibited the strongest adsorption capability due to a substantial presence of oxygen and nitrogen groups on its surface, enabling the formation of hydrogen bonds with DOX. However, its actual adsorption capacity was the lowest among the polymers, indicating that structural adjustments played a more significant role in improving adsorption performance compared to functional adjustments. Adsorption experiments conducted with NH‐HCPs and NH2‐HCPs further supported this hypothesis. The primary DOX adsorption mechanism of NH‐HCPs, NH2‐HCPs, and COOH‐HCPs involved the H‐bonding of oxygen and nitrogen functional groups, along with other mechanisms such as π‐π conjugated effects, pore‐filling effects, electrostatic interactions, and acid–base interactions. Overall, this study demonstrates the effectiveness of NH‐HCPs, NH2‐HCPs, and COOH‐HCPs in DOX removal from water, highlighting the significant influence of structural adjustments on adsorption performance.
Porous hypercrosslinked polymers adsorbed doxycycline in water.
The design and synthesis of porous materials with novel structures and functional groups to prepare mixed matrix membranes (MMMs) is an effective way to break through trade‐off effect of membrane ...technology. Here, hyper cross‐linked polymers containing amino groups (HCPs‐NH2) with philic‐CO2 frame were successfully prepared for the fabrication of polyimide (PI)/HCPs‐NH2 MMMs. The separation performance of pure gas is studied in order to explore NH2 groups facilitating CO2 diffusion and transmission and enhancing CO2 permeability. Consequently, the permeability of the PI/HCPs‐NH2 MMMs toward CO2 and O2 are 77.56 Barrer and 17.91 Barrer versus pure PI film toward CO2 and O2 (62.42 Barrer and 13.85 Barrer). The selectivity for CO2/CH4 and O2/N2 pairs is 24.44 and 4.01, and the selectivity of pure PI film toward CO2/CH4 and O2/N2 pairs is 20.76 and 3.29, respectively. The permeability and selectivity of PI/HCPs‐NH2 MMMs are higher than pure PI film breaking through the trade‐off effect. Moreover, the PI/HCPs‐NH2 MMMs show better separation performance on the CO2/CH4 pair than the O2/N2 pair, indicating HCPs‐NH2 with philic‐CO2 frame plays a very important role in promoting CO2 permeability. Thus, the PI/HCPs‐NH2 MMMs have potential applications in the field of natural gas purification.
Fluoride ion (F(-)), the smallest anion, exhibits considerable significance in a wide range of environmental and biochemical processes. To address the two fundamental and unsolved issues of current ...F(-) sensors based on the specific chemical reaction (i.e., the long response time and low sensitivity) and as a part of our ongoing interest in the spiropyran sensor design, we reported here a new F(-) sensing approach that, via assembly of a F(-)-specific silyl-appended spiropyran dye with graphene oxide (GO), allows rapid and sensitive detection of F(-) in aqueous solution. 6-(tert-Butyldimethylsilyloxy)-1',3',3'-trimethylspiro chromene- 2,2'-indoline (SPS), a spiropyran-based silylated dye with a unique reaction activity for F(-), was designed and synthesized. The nucleophilic substitution reaction between SPS and F(-) triggers cleavage of the Si-O bond to promote the closed spiropyran to convert to its opened merocyanine form, leading to the color changing from colorless to orange-yellow with good selectivity over other anions. With the aid of GO, the response time of SPS for F(-) was shortened from 180 to 30 min, and the detection limit was lowered more than 1 order of magnitude compared to the free SPS. Furthermore, due to the protective effect of nanomaterials, the SPS/GO nanocomposite can function in a complex biological environment. The SPS/GO nanocomposite was characterized by XPS and AFM, etc., and the mechanism for sensing F(-) was studied by (1)H NMR and ESI-MS. Finally, this SPS/GO nanocomposite was successfully applied to monitoring F(-) in the serum.
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