A bimetallic metal-organic framework (MOF) with a yellow-emission signal has been successfully fabricated by appealing to the lanthanide doping strategy. This MOF could behave as a fluorescent sensor ...for decoding methanol with an obvious color change and unique emission intensity ratio of Tb3+ ion to Eu3+ ion, both in the solution and vapor state. Good detection reproducibility and fast response could be achieved in this sensor.
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•A dual-emitting Eu/Tb bimetallic metal-organic framework was synthesized.•This MOF shows strong emission colour and high fluorescence stability.•A selective enhancement of fluorescence of Tb ion is induced by MeOH.•Ratiometric fluorescent sensing of formaldehyde in both solution and vapor state is performed.
Ratiometric fluorescence sensor has drawn much attention due to its decreased environment influence and easy-to-differentiate color and intensity change. In this work, a bimetallic metal-organic framework (MOF), namely {(Me2NH2)Tb0.9Eu0.1(OBA)2∙(Hatz)∙(H2O)1.5}n (1, H2OBA = 4,4′-oxybis(benzoate) acid, Hatz = 3-amino-1,2,4-triazole) with a yellow-emission signal has been successfully fabricated by appealing to the lanthanide doping strategy. In this MOF, the emission band of OBA2− ligand matches well with the excitation energy of lanthanide ions (Eu3+ and Tb3+) which leads to high energy transfer from the ligand to the lanthanide ions to provide dual emission peaks for the both Eu3+ and Tb3+ ions. This MOF shows high fluorescence stability with the ratio of its two emission peaks (545 nm and 618 nm) do not change with the change of Ln-MOF sensor concentration used as the merit of ratiometric fluorescence detection. Subsequently, we choose this MOF as a fluorescent sensor for various volatile organic molecules, and the results show that it is capable of decoding methanol with an obvious color change and unique emission intensity ratio of Tb3+ ion to Eu3+ ion, both in the solution and vapor state. Good detection reproducibility and fast response could be achieved in this sensor.
•ZnWO4 was used as a sonocatalyst to degrade meloxicam for the first time.•The degradation ratio had reached 75.7% under experimental condition.•Effects of key parameters on sonocatalytic degradation ...of meloxicam were studied.•Meloxicam degradation pathways and reaction mechanism in the system were proposed.
Zinc tungstate (ZnWO4) was previously used as a photocatalyst. In this paper, for the first time as an sonocatalyst, the performance of ZnWO4 for sonocatalytic degradation of meloxicam (MEL) under ultrasonic irradiation were studied. Firstly, ZnWO4 nanomaterials were synthesized at different acidity (pH = 5, 6, 7, 8, 9) via the hydrothermal method. Utilizing SEM, XRD and EDS techniques to characterize composition and morphology of each product, the same crystal forms, but different morphologies (nano-sheet, nano-microspheres or nano-rod) of ZnWO4 could be obtained. Secondly, the sonocatalytic activities of ZnWO4 on degradation of MEL were studied. It was found that the degradation ratio varied with the synthetic pH values, with ZnWO4 under synthetic pH = 6 exhibiting the best sonocatalytic performance (75.7%). Whilebeing synthesized at this pH value, ZnWO4nano-microspheres had the largest BET surface area (27.068 m2/g), the smallest particle size (40–60 nm) so as to provide more active sites on its surface, which were able to produce more reactive oxygen species (ROS) and holes under ultrasonic irradiation. These ROS and holes had a positive effect on the degradation of MEL into CO2, H2O and inorganic. Thirdly, various influential factors including ultrasonic power intensity, ultrasonic time, catalyst addition dosage, initial concentration of MEL solution and reusability of catalyst were also explored. Under the condition of 10 mg/L MEL concentration, 20 mg catalyst dosage, 120 min irradiation time, 0.278 W/cm2 ultrasonic power intensity, the degradation ratio on MEL reached 75.7%. Finally, the presence of hydroxyl radical (OH) and singlet molecular oxygen (1O2) in the reaction was confirmed by adding ROS scavenger. The experimental results suggested that ZnWO4 nanoparticle could be used not only as an effective photocatalyst, but also, under the condition of ultrasonic irradiation, a promising sonocatalyst for degradation of organic pollutants in aqueous media.
Catalytic decomposition of hydrazine monohydrate (N2H4·H2O) has emerged as a promising hydrogen generation technology for vehicular and mobile applications. However, existing catalysts are plagued by ...either excessive cost or poor catalytic performance. We herein report a successful implementation of a surface alloying strategy to fabricate a high-performance and cost-effective catalyst for hydrogen generation from N2H4·H2O using the Ni10Mo/Mo–Ni–O catalyst as the starting material. Incorporation of a small amount of Co by strong electrostatic adsorption method improved the overall catalytic performance. The resulting Ni10MoCox/Mo–Ni–O catalyst achieved a turnover frequency of 461 h−1 at 70 °C, with 95% activity retention after 10 cycles, outperforming reported non-precious metal catalysts. Using this catalyst, we developed a high-capacity N2H4·H2O-based hydrogen generation system with rapid response. Our finding highlights the significant potential of multi-component alloys in achieving exceptional catalytic performance and may encourage future exploration of catalytic decomposition of N2H4·H2O as an advanced on-demand hydrogen generation technology.
Millennia of directional human selection has reshaped the genomic architecture of cultivated cotton relative to wild counterparts, but we have limited understanding of the selective retention and ...fractionation of genomic components.
We construct a comprehensive genomic variome based on 1961 cottons and identify 456 Mb and 357 Mb of sequence with domestication and improvement selection signals and 162 loci, 84 of which are novel, including 47 loci associated with 16 agronomic traits. Using pan-genome analyses, we identify 32,569 and 8851 non-reference genes lost from Gossypium hirsutum and Gossypium barbadense reference genomes respectively, of which 38.2% (39,278) and 14.2% (11,359) of genes exhibit presence/absence variation (PAV). We document the landscape of PAV selection accompanied by asymmetric gene gain and loss and identify 124 PAVs linked to favorable fiber quality and yield loci.
This variation repertoire points to genomic divergence during cotton domestication and improvement, which informs the characterization of favorable gene alleles for improved breeding practice using a pan-genome-based approach.
Over-the-top (OTT) services are the main avenue for audiences to consume foreign content; therefore, companies use foreign content as a weapon to compete for local market share. Employing an analytic ...hierarchy process (AHP) in a survey of 14 OTT-content-related incumbents, this study prioritized the decisive factors in domestic OTT platforms' choice of foreign content in South Korea. The results revealed that using differentiated foreign content for competition with other domestic services is a top priority, while content with proven domestic marketability to satisfy audience demand follows behind. Finally, this study gives insights into OTT platforms' foreign content strategy.
Controllable hydrogen generation through catalytic decomposition of hydrazine monohydrate (N2H4·H2O) holds promise for mobile and portable applications. However, the existing catalysts (such as ...Ni60Pt40/CeO2, CoPt/CeOx) often suffer from poor stability, and active site poisoning appears an important cause of deactivation. Here, we present a simple yet effective method to address this issue. By adding a Ce3+ salt during the precipitation-deposition process, we observed enhanced interactions between Ni–Pt alloy and CeO2 matrix, impacting the electronic structure and dispersion of Ni–Pt nanoparticles. Thus-obtained Ni4Pt/CeO2 catalyst exhibited an over two-fold increase in activity and an 80% retention after 10 cycles, outperforming conventional methods. The novel approach simultaneously improved activity and stability while maintaining a constant alloy composition. This catalyst demonstrated high activity, 100% H2 selectivity, and good stability in N2H4·H2O decomposition. Additionally, it enabled the construction of a high-capacity N2H4·H2O-based hydrogen generation system with rapid dynamic response.
Integrating Ce3+ salt during the precipitation-deposition process in the fabrication of Ni–Pt/CeO2 catalysts yields enhanced metal-support interactions, which results in a marked improvement in both activity and stability for hydrogen production from hydrazine monohydrate when contrasted with conventional approaches. Display omitted
•New approach for Ni–Pt/CeO2 catalysts towards N2H4·H2O decomposition is proposed.•Enhanced metal-support interactions using Ce3+ during precipitation-deposition.•New method improves both the intrinsic activity and Ni–Pt dispersion.•Thus-obtained Ni4Pt/CeO2 catalyst showed remarkable activity and high stability.
As a modulatable class of porous crystalline materials, metal–organic frameworks (MOFs) have gained intensive research attention in the domain of gas storage and separation. In this study, we report ...on the synthesis and gas adsorption properties of two robust MOFs with the general formula Co3(μ3-OH)(cpt)3Co3(μ3-OH)(L)3(H2O)9(NO3)4(guests) n L = 3-amino-1,2,4-triazole (1) and 3,5-diamino-1,2,4-triazole (2); Hcpt = 4-(4-carboxyphenyl)-1,2,4-triazole, which show the same pacs topology. Both MOFs are isostructural to each other and show MIL-88-type frameworks whose pore spaces are partitioned by different functionlized trinuclear 1,2,4-triazolate-based clusters. The similar framework components with different amounts of functional groups make them an ideal platform to permit a systematic gas sorption/separation study to evaluate the effects of distinctive parameters on the C2H2 uptake and separation performance. Because of the presence of additional amido groups, the MOF 2 equipped with a datz-based cluster (Hdatz = 3,5-diamino-1,2,4-triazole) shows a much improved C2H2 uptake capacity and separation performance over that of the MOF 1 equipped with atz-based clusters (Hatz = 3-amino-1,2,4-triazole), although the surface area of the MOF 1 is almost twice than that of the MOF 2. Moreover, the high density of open metal sites, abundant free amido groups, and charged framework give the MOF 2 an excellent C2H2 separation performance, with ideal adsorbed solution theory selectivity values reaching up to 11.5 and 13 for C2H2/C2H4 (1:99) and C2H2/CO2 (50:50) at 298 K and 1 bar, showing potential for use in natural gas purification.
Base editors (BEs) display diverse applications in a variety of plant species such as Arabidopsis, rice, wheat, maize, soybean, and cotton, where they have been used to mediate precise base pair ...conversions without the collateral generation of undesirable double-stranded breaks (DSB). Studies of single-nucleotide polymorphisms (SNPs) underpinning plant traits are still challenging, particularly in polyploidy species where such SNPs are present in multiple copies, and simultaneous modification of all alleles would be required for functional analysis. Allotetraploid cotton has a number of homoeologous gene pairs located in the A and D sub-genomes with considerable SNPs, and it is desirable to develop adenine base editors (ABEs) for efficient and precise A-to-G single-base editing without DSB in such complex genome.
We established various ABE vectors based on different engineered adenosine deaminase (TadA) proteins fused to Cas9 variants (dCas9, nCas9), enabling efficient A to G editing up to 64% efficiency on-target sites of the allotetraploid cotton genome. Comprehensive analysis showed that GhABE7.10n exhibited the highest editing efficiency, with the main editing sites specifically located at the position A5 (counting the PAM as positions 21-23). Furthermore, DNA and RNA off-target analysis of cotton plants edited with GhABE7.10n and GhABE7.10d by whole genome and whole-transcriptome sequencing revealed no DNA off-target mutations, while very low-level RNA off-target mutations were detected. A new base editor, namely GhABE7.10dCpf1 (7.10TadA + dCpf1), that recognizes a T-rich PAM, was developed for the first time. Targeted A-to-G substitutions generated a single amino acid change in the cotton phosphatidyl ethanolamine-binding protein (GhPEBP), leading to a compact cotton plant architecture, an ideotype for mechanized harvesting of modern cotton production.
Our data illustrate the robustness of adenine base editing in plant species with complex genomes, which provides efficient and precise toolkit for cotton functional genomics and precise molecular breeding.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A novel family of N-heterocyclic carbene (NHC)-incorporated Se-Fe-Cu compounds, bis-1,3-dimethylimidazol-2-ylidene (bis-Me
2
-imy)-containing compound (μ
4
-Se)Fe
3
(CO)
9
{Cu(Me
2
-imy)}
2
(
2
), ...bis-
N
-methyl- or bis-
N
-isopropyl-substituted benzimidazol-2-ylidene (bis-Me
2
-bimy or bis-
i
Pr
2
-bimy)-incorporated compounds (μ
4
-Se)Fe
3
(CO)
9
{Cu(Me
2
-bimy)}
2
(
3
) or (μ
4
-Se)Fe
3
(CO)
9
{Cu(
i
Pr
2
-bimy)}
2
(
4
), and a bis-1,3-dimethyl-4,5-dichloroimidazol-2-ylidene (bis-Me
2
-Cl
2
-imy)-containing compound (μ
3
-Se)Fe
3
(CO)
9
{Cu(Me
2
-Cl
2
-imy)}
2
(
5
), were synthesized in moderate yields in facile one-pot reactions of the ternary pre-designed compound (μ
3
-Se)Fe
3
(CO)
9
{Cu(MeCN)}
2
(
1
) with the corresponding imidazolium salts and KO
t
Bu in THF in an ice-water bath. Single-crystal X-ray analyses revealed that the Me
2
-imy compound
2
or the Me
2
-bimy compound
3
each exhibited a trigonal bipyramidal SeFe
3
(CO)
9
Cu geometry with an Fe
2
Cu plane further capped by a Cu(Me
2
-imy) or Cu(Me
2
-bimy) fragment, respectively, with one long Cu-Cu covalent bond. In addition, compound
4
also comprised a trigonal bipyramidal SeFe
3
(CO)
9
Cu core structure, but the second Cu(
i
Pr
2
-bimy) group bridged the equatorial Fe-Fe edge with two unbonded Cu atoms, due to the presence of a sterically bulky
i
Pr
2
-bimy fragment. On the other hand, the strong electron-withdrawing chloro-containing NHC compound
5
showed a comparatively open tetrahedral SeFe
3
(CO)
9
metal core, where two Fe-Fe edges each were further bridged by a Cu(Me
2
-Cl
2
-imy) fragment. Due to the nonclassical C-H O(carbonyl) hydrogen bonds between the CO groups of the SeFe
3
(CO)
9
Cu
2
core and CH moieties of the neighboring NHC ligands, both compounds
2
and
3
comprised a one-dimensional network, while compounds
4
and
5
each were made up of a two-dimensional framework in the solid state, which efficiently enhanced the stability of these Se-Fe-Cu NHC compounds. Importantly, all of these synthesized Se-Fe-Cu NHC compounds
2-5
had pronounced catalytic activities for the homocoupling of arylboronic acids with high catalytic yields. Finally, these Se-containing Fe-Cu NHC compounds further represented excellent models for studying chalcogen effects in comparison to their Te analogs, as demonstrated by their catalytic performances and electrochemical behaviors, and by DFT calculations.
A novel family of highly efficient Se-Fe-Cu-NHC catalysts was synthesized, which were suitable models for the study of the chalcogen effect.
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