Hydrothermal cracking is recognized as a promising technology for heavy oil upgrading, where a molecular-level understanding of the role of water and its ionic products is considered essential for its optimization and advancement. In this work, the multifaceted role of water in the degradation of a representative model compound, N-cyclohexylnaphthalen-1-amine (CNA), was investigated using density functional theory (DFT). It was demonstrated that water functions as an in-situ source of acid-base catalysts, in which the cleavage of aliphatic C-N bonds is dramatically promoted by hydronium ions, while the dissociation products are stabilized by water molecules and hydroxide ions. Notably, the aromatic C-N bonds were identified to exhibit superior reactivity in nucleophilic substitution compared to their aliphatic counterparts; nucleophilic substitution occurs more readily at the alpha-carbon site of the naphthalene ring than at that of a benzene ring. By constructing the hydrothermal cracking reaction network of the model compound, it is clarified that water and its ionic products in the hydrothermal system function as in-situ acid/base species that can catalyze, regulate, or directly participate in the hydrothermal cracking process. Furthermore, the preferential dependence of different reaction routes on the local acid-base environment is revealed. This study provides a theoretical basis for mechanistic investigations of heavy oil upgrading under acid-base regulated conditions and for the optimization of process conditions.

Dysregulated cellular ferrous ion (Fe2+) levels lead to various diseases. Despite existing Fe2+ detection methods, achieving sensors with simultaneous high sensitivity, selectivity, and rapid response via rational design remains challenging. To address this, a coordination competition strategy was proposed to construct phenanthroline-modified lanthanide metal-organic frameworks (Phen-Ln-MOFs). This approach leverages Phen's preferential coordination affinity for Fe2+ over Ln(3+) ions, enabling colorimetric-fluorescent dual-mode Fe2+ recognition. The optimized TFP-1 sensor exhibits exceptional selectivity and real-time sensing ability for Fe2+, demonstrated by luminescence quenching with a record-low detection limit (LOD) of 1 nM and a distinct colorless-to-brick-red chromatic transition. Crucially, TFP-1 maintains high precision (RSD <7.07%) with a low LOD of 100 nM in complex biological matrices like artificial urine, highlighting its clinical and environmental monitoring potential. This strategy proves generalizable across diverse Phen-Ln-MOF systems, and establishes a robust platform for highly selective and sensitive dual-mode Fe2+ detection.

The development of flexible temperature sensors is hindered by the intrinsically low thermal sensitivity of soft ionic conductors, which arises from averaged energy landscapes and competing transport mechanisms. Inspired by the gating mechanism of biological transient receptor potential (TRP) ion channels, we propose a hydrogen-bond trap regulation strategy. By constructing localized hydrogen-bond traps with heterogeneous energy distributions within a deep eutectic solvent (DES) gel network, continuous ion transport is transformed into a confined, thermally activated hopping process. This approach yields an ultrahigh temperature coefficient of resistance (TCR) of 178% °C-1 and a high B value of 7880 K. A miniature flexible probe (Ø1.0 mm × 1.0 mm) demonstrates practical potential in organ temperature monitoring and wireless respiratory tracking. The tailored hydrogen-bond traps also effectively suppress multimodal crosstalk, enabling the fabrication of a decoupled trimodal sensing system that independently resolves proximity, pressure, and temperature signals for human-robot interaction. This work establishes a versatile materials strategy for achieving thermal perception in soft electronics and provides a general platform for tuning ion transport in polymer networks.

Anthrax is an acute infectious disease with potential high pathogenicity caused by Bacillus anthracis, which poses a serious threat to human life. Therefore, rapid and efficient detection of the biomarker of B. anthracis, dipicolinic acid (H2DPA), is crucial for safeguarding human health. In this study, heterometallic organic framework ZnNa2(DPA)2 (H2DPA = dipicolinic acid, also as ligand) was designed and synthesized. In order to enhance fluorescence performance, series of Tb3+-doped ZnNa2(DPA)2 (Tb-1, Tb-3, Tb-5, and Tb-7) were prepared. A series of fluorescence detection results demonstrates that Tb-7 exhibited the best fluorescence quenching effect on H2DPA with a quenching constant (K sv) of 1.67 & times; 105 M-1 and a limit of detection (LOD) as low as 4.34 mu M. The quenching mechanism of Tb-7 as a fluorescent sensing material was also investigated.

The inappropriate utilization of Ofloxacin (OFLX) can result in environmental accumulation, posing potential risks to both ecosystems and human health. And the Fe3+ ion plays a crucial role in maintaining human health and facilitating environmental functions. Consequently, there is an urgent need to develop an efficient and sensitive sensor for the detection of OFLX and Fe3+. Herein, a new terbium metal-organic framework (MOF), namely [Tb2(SDBA)3(H2O)3] (DMAC)3 (H2SDBA = 4,4 '-sulfonyldibenzoic acid, DMAC = N,N '-Dimethylaceta-mide, 1), has been synthesized by a facile solvothermal method. Single-crystal X-ray diffraction analysis demonstrates that 1 exhibit three-dimensional (3D) framework based on one-dimensional (1D) chain. Luminescent sensing indicate 1 possess significant fluorescence quenching for both OFLX and Fe3+. The Stern-Volmer constants (Ksv) and the limits of detection were 8.79 x 104 M-1 and 1.05 x 10-5 M for OFLX, 3.03 x 104 M-1 and 1.47 x 10-4 M for Fe3+, respectively. Furthermore, the fluorescence quenching of both OFLX and Fe3+ primarily stems from internal filtration and static quenching mechanisms.

In the context of global carbon neutrality, light conversion agents characterized by spectral matching capability and high stability have emerged as promising candidates to enhance CO2 fixation and agricultural productivity. We fabricated light conversion films (LCFs) incorporating europium-based coordination polymer nanosheets (Eu-CPNs). The nanosized structures of Eu-CPNs, fabricated by ultrasonic exfoliation of bulk coordination polymer Eu-CP, are uniformly dispersed within the thermoplastic polyurethane (TPU) matrix, exhibiting seamless interfacial interactions. Notably, this is the first time Eu-CP, or even CPs, has been used for practical application in plant growth regulation as light conversion agents. Compared with plants under the control check (CK) film, Brassica rapa var. Chinensis growing under LCFs had a 77.9% increment in daily CO2 assimilation at the whole plant level, and its fresh aboveground weight and total dry weight increased by 92.0% and 79.7%, on average, respectively. Further, the gene transcriptional response of plants revealed that LCFs significantly upregulated the transcription of genes related to photosynthesis and carbon metabolism. LCFs based on coordination polymer nanosheets evidently improved the utilization efficiency of solar energy and the growth of plants by light conversion, holding great potential for carbon neutrality and the green development of protected horticulture.

To investigate the effects of pipe support system characteristics on gas explosion overpressure loads in utility tunnel gas compartments, a 200 m x 2 m x 3 m model of a typical Chinese utility tunnel was constructed using CFD dynamics. Analysis of spatial and temporal distributions of explosion overpressure load under different support spacings. The results indicated that a short support spacing (L = 5 m) contributes to a more uniform distribution of the gas cloud and enhanced the average flame propagation velocity, whereas a medium support spacing (L = 15 m, 25 m) significantly increased the peak overpressure and instantaneous flame velocity. The explosion overpressure curve showed a multipeak structure, with peak P1 caused by the precursor shock wave and peaks P2-P4 caused by the reflected wave. Within 70 m, the secondary reflected wave P3 dominated, and within 130-200 m, the first reflected wave, P2, played a major role. The peak overpressure loads at different support spacings decreased and subsequently increased along the length of the utility tunnel, and the maximum peak overpressure load was reached at the end. The peak overpressure in the same cross-section is unevenly distributed; the closer to the far-end wall, the more significant the difference, and the maximum overpressure usually appears near the top of the tunnel. According to the quantitative relationship between the peak explosion overpressure and support spacing, the optimised design of the pipe support spacing should not be less than 25 m.

In this study, five sulfonium ionic liquids are analysed by X-ray photoelectron spectroscopy. The surface purity and C 1s fitting model are discussed in details. The influence of alkyl chain length on the aliphatic carbon binding energy is illustrated by comparing ethyl-and butyl-based cations. The impact of the cation on the electronic environment of the anion-based components is demonstrated. It is found that the cation-anion interactions can be significantly affected by the structure of the cation.

A new two-dimensional (2D) lanthanide metal-organic framework [Eu-2(ATA)(3)(phen)(2)](n) (Eu-MOF, H(2)ATA = 2-amino terephthalic acid, phen = 1,10-phenanthroline) was successfully self-assembled via a simple solvothermal method. Then D-camphoric acid (D-Cam) was grafted onto Eu-MOF by post-synthetic modification (PSM) through a mechanochemical approach, successfully fabricating the chiral material Eu-MOF-D-Cam. Remarkably, this modification not only significantly enhanced the luminescent properties but also introduced the chiral sites for enantioselective sensing of mandelic acid (MA) enantiomers. The enantioselectivity factor alpha (alpha = K-SV(R-MA)/K-SV(S-MA)) of Eu-MOF-D-Cam was 2.56. These findings establish Eu-MOF-D-Cam as a promising photoluminescent sensor for chiral discrimination of R/S-MA enantiomers.

A systematic investigation of the beam-induced surface decomposition of a typical trihalide ionic liquid, 1-octyl-3-methylimidazolium tribromide, was conducted by X-ray photoelectron spectroscopy, and the electronic environment of the bromine region is discussed. The newly formed component was assigned to bromide, based on the measured Br 3d binding energy. The atomic loss of bromine as a function of exposure time under the X-ray beam is analyzed in detail. The analysis suggests that 1-octyl-3-methylimidazolium tribromide is decomposed under X-ray beam irradiation to yield 1-octyl-3-methylimidazolium bromide and liquid bromine, the latter of which subsequently leaves the system under the ultrahigh vacuum conditions.

Ionic liquids (ILs) have garnered significant attention as eco-friendly media for living/controlled cationic polymerization due to their tunable solvation properties and enhanced reaction control. However, the fundamental principles governing cationic polymerization and the specific role of ionic liquids in these reactions remain poorly understood, leading to the continued reliance on a trial-and-error approach for ILs selection. To address this fundamental challenge, we conducted computational investigations of the CumOH/BF₃OEt₂-initiated living cationic polymerization of p-methylstyrene within the prototypical hydrophobic ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf₂]). Additionally, a comparative analysis of solvent effects was conducted, contrasting the performance of [BMIM][NTf₂] with the conventional organic solvent dichloromethane (CH₂Cl₂). Quantum chemical calculations revealed that both the BMIM⁺ cation and CH₂Cl₂ significantly lower the activation barrier of the initiation step. More importantly, the NTf₂⁻ anion was found to play a dual catalytic role by stabilizing key cationic intermediates and modulating the transition state geometry during chain initiation and dimerization. These mechanistic insights quantitatively account for the the observed differences in reaction rates and yields of p-MeSt polymerization in [BMIM][NTf₂] compared to CH₂Cl₂. Employing density functional theory (DFT) at the B3LYP/6–311 + + G(d,p) level of theory using Gaussian-03, we conducted a comprehensive mechanistic investigation of three pivotal elementary steps governing the early-stage polymerization: (i) initiator activation, (ii) monomer chain initiation, and (iii) dimer formation.

The development of efficient adsorbents for rapid strontium ion (Sr2+) sequestration holds crucial significance in addressing environmental remediation and radioactive waste management. Herein, we developed a series of zirconium-based metal-organic frameworks (Zr-MOFs: UiO-66-NH-Cys, -Ala, -His, -Phe, -Pro) functionalized with amino acids through post-synthetic modification (PSM), which improved Sr2+ adsorption performance. Notably, UiO-66-NH-Cys achieves a superior adsorption capacity (86.21 mg g- 1) under optimized conditions (pH 10.0, 298 K, initial concentration 300 mg L-1), outperforming pristine UiO-66-NH2 and other amino acidfunctionalized analogues. Mechanistic research indicates that Sr2+ binding primarily involves coordination with cysteine's thiol (-SH) and amine (-NH2) groups, complemented by ion exchange processes and electrostatic interaction. This work establishes amino acid-functionalized Zr-MOFs as precision-engineered adsorbents for selective Sr2+ removal, while providing a rational design strategy for addressing multifaceted aqueous contamination through targeted molecular engineering.

We investigate four cyano-containing ionic liquids, 1-octyl-3-methylimidazolium thiocyanate, 1‑octyl-3-methylimidazolium dicyanamide, 1-octyl-3-methylimidazolium tricyanomethanide, and 1-octyl-3-methylimidazolium tetracyanoborate, using X-ray photoelectron spectroscopy. A four-component C 1s spectrum fitting model is developed in particular for these four ionic liquids, by modifying the existing model with additional anionic carbon contributions. The impact of the anion charge delocalization on the electronic environment of the cyano-nitrogen is discussed. It concludes that by increasing the number of the cyano group, a 0.5 eV binding energy shift can be observed for the three charge delocalized anions. For the non-delocalized anion, a much higher binding energy can be measured. There is a linear correlation of N 1s binding energy and the point charges located on cyano nitrogen atoms.

Herein, a layered chiral coordination polymer, [Cd-2(D-cam)(2)(2,2' -bipy)(2)](n) (Cd-CP), was synthesized using a solvothermal method with camphoric acid (D-H(2)cam), 2,2'-bipyridine (2,2'-bipy) and Cd2+, and Tb3+@Cd-CP was in-situ synthesized introducing Tb3+ ions. The fluorescence experiments revealed that compared to Cd-CP, Tb3+@ Cd-CP exhibited ultra-high fluorescence performance. The luminescence sensing performance demonstrated that Tb3+@Cd-CP could distinguish R/S-propylene glycol (R/S-PG) by fluorescence responses, with fluorescence quenching constant of 5.3x10(3) and 2.0x10(3) L center dot mol(-1) respectively and the enantioselectivity factor (a) of 2.65. Moreover, Tb3+@Cd-CP demonstrated limits of detection of 9.3 and 19.0 mu mol center dot L-1 for R-PG and S-PG, respectively, and showed good reproducibility.

Two new isostructural lanthanide(III)-metal organic frameworks (Ln-MOFs), namely [Ln2(FDA)3(TMS)2(H2O)2]& sdot;H2O (Ln = Eu 1 and Tb 2, H2FDA = 2,5-furandicarboxylic acid, TMS = tetramethylene sulfone), have been synthesized and characterized. Single-crystal X-ray diffraction analysis reveals that both Ln-MOFs exhibit three-dimensional structures crystallizing in the monoclinic C2/c space group. Luminescent sensing studies indicate that 1 and 2 possess commendable capabilities for detecting Fe3+ and Cr3+, with low detection limits of 20.00 nM and 43.41 nM for 1 and 66.10 nM and 0.37 mu M for 2, respectively. Furthermore, the investigation into the mechanism revealed the quenching of Fe3+ can be ascribed to the dual effects of inner filter effect (IFE) and the static quenching. Conversely, the dynamic quenching mechanism has played a predominant role during the sensing process of Cr3+.

Pidotimod is a chiral drug that possesses two chiral centers, resulting in three isomeric impurities (analytes, A). This study employs electrospray ionization ion trap mass spectrometry (ESI-MS) through collision-induced dissociation (CID) to investigate the chiral recognition of pidotimod and its three isomers to eliminate chromatographic separation. Three approaches were explored: (1) Protonated molecules in CID exhibited discriminative potential for diastereomers, with the ability to distinguish between S,S and R,R configurations, albeit with an Rchiral value of ~1.8. However, differentiation between R,S and S,R configurations was not achievable. (2) Alkali adductions (lithium and sodium) only discerned diastereomers. The Rchiral values of the diastereomers obtained from alkali adduct ions were significantly lower than those obtained from protonated ions. (3) Therefore, a third approach was used to address the challenge of distinguishing between R,S and S,R configurations, including the introduction of chiral references (ref) and transition metals (MII) to form metal-bound complexes [MII(A)(ref)-H]+. Additionally, we synthesized a novel ligand, 4-(N-tert-butoxycarbonyl [Boc]-L-prolinamido)phenol (denoted as ligand A), by modifying N-t-Boc-L-Pro with 2-aminophenol, which, in combination with CuII and NiII, enabled simultaneous differentiation of all four isomers. CuII complexes exhibited significant chiral selectivity between R,S and S,R configurations. Density functional theory calculations were performed to further elucidate the stereodynamic behavior and stoichiometry of these ions in the gas phase. These calculations revealed the interaction energy and coordination sites of the precursor ions in the gas phase, correlating well with MS/MS experiment results. Additionally, the logarithm of the CuII complexes' characteristic fragment ion abundance ratio demonstrated a strong linear relationship with enantiomeric excess (ee). This study presents a novel strategy for chiral drug quality control that eliminates chromatographic separation.

ABSTRACTTemperature in various scientific and industrial applications requires accurate detection and measurement. Herein, a range of novel isostructural lanthanide‐based metal–organic frameworks (Ln‐MOFs), [EuxTb2−x(3,5‐pdc)3(phen)2(H2O)2]n (x = 0, Tb‐MOF; x = 2, Eu‐MOF; x = 0.002, 0.010, 0.020, 0.040, 0.080, EuxTb2−x‐MOF), were solvothermally synthesized using 3,5‐pyridinedicarboxylic acid (3,5‐H2pdc) and 1,10‐phenanthroline (phen) as ligands. Based on binuclear second building units, Ln‐MOFs exhibited 2D layered structure with sql topology. The luminescent properties of series Ln‐MOFs show systematic tuning shifted from green to red by adjusting the ratio of Eu3+ to Tb3+. The temperature sensing experiments showed that Eu0.020Tb1.980‐MOF exhibited self‐calibration temperature response in a range of 293–413 K, achieving maximum relative sensitivity (Sr) 2.46%·K−1 at 413 K, outscoring many state‐of‐the‐art temperature sensors reported in literature. This study poses great promise of the newly designed Eu0.020Tb1.980‐MOF for the ultra‐sensitive temperature sensing in diverse and large‐scale applications.

Based on computational fluid dynamics technology, the effect of hydrogen blending ratio (HBR) on the concentration distribution of leaked gas diffusion in utility tunnels was investigated, and based on this, the explosion characteristics of hydrogen-blended natural gas (HBNG) were studied in an inhomogeneous concentration field. The results showed that the concentration field of HBNG gradually stabilized in the downstream of the leak site, and the peak concentration increased linearly with HBR. When HBR≤5%, a high concentration region above the upper explosive limit is formed inside the gas cloud. This characteristic of the distribution induces secondary combustion in utility tunnels. The maximum flame velocity and steady acceleration distance increase with the increase of HBR. The flame shape is significantly affected by the concentration field distribution. The explosion overpressure induced by the real concentration field created multiple peak structures that exacerbated the explosion disaster complexity. The first overpressure peak at the ends was formed by the superposition of the precursor shock wave and its reflected wave, and those at other locations are caused by the shock waves. However, all maximum overpressure peaks are formed by the superposition of multiple reflections of the explosion wave. The maximum peak overpressure at both ends of the tunnel is higher than that in the middle. The explosion overpressure induced by the inhomogeneous gas cloud is lower than that caused by homogeneous gas cloud under the same volume. The research results can provide an effective reference for the anti-explosion design and risk assessment of utility tunnel.