Particle aspect ratio is an important geometric parameter; however, its role in pneumatic conveying remains insufficiently understood. This study employed the bonded particle model (BPM) to construct shredded tobacco particles with 11 different aspect ratios, and simulated the industrial-scale pneumatic conveying process using the coarse-grained Computational Fluid Dynamics-Discrete Element Method (CFD-CGDEM). Particle conveying behavior in straight pipes, horizontal elbows, and vertical elbows was analyzed. The degree of radial mixing was quantitatively characterized by the Lacey mixing index (M). Simulation results revealed that particle aspect ratio influenced conveying characteristics through particle–fluid interactions and flow-induced motion characteristics. In straight pipes, particles with high aspect ratio were more likely to accumulate near pipe walls due to gravity (M < 0.1). In elbows, these particles showed stronger radial migration driven by curvature-induced flow and secondary flow, but the mixing uniformity was still low. When gas velocity was 18–27 m/s, the average particle velocity decreased approximately linearly as the aspect ratio increased. Under stable conveying conditions (21–27 m/s), the average residence time increased correspondingly. At higher gas velocities, the influence of gas flow on particle transport behavior became more significant, and the above correlations gradually weakened. The simulation results were validated by industrial-scale experiments under three gas velocity conditions (21, 24, and 27 m/s), with relative deviations in average residence time all below 5%. This study clarifies how particle aspect ratio affects pneumatic conveying, and provides a basis for optimizing the conveying of flexible elongated particles.

Heat-not-burn tobacco products (HTP) as alternatives to traditional cigarettes could reduce the release of harmful components in tobacco smoke by avoiding high-temperature combustion. However, detailed chemical analysis of the gas-phase HTP smoke is necessary because tobacco pyrolysis is the primary source of certain hazardous volatile organic compounds (VOCs). In this study, a vacuum ultraviolet time-of-flight photoionization mass spectrometer is combined with Hefei synchrotron radiation to analyze gas-phase HTP smoke online at the molecular level. A large number of VOCs have been observed online and assigned in photoionization mass spectra. The mass-selected photoionization efficiency (PIE) spectra of the major VOC species were measured by scanning synchrotron photon energy and fitted well to structure-specific molecular photoionization cross sections (PICS). The structures of species in the gas-phase HTP smoke are determined, and abundant isomers are differentiated. The present results demonstrate that despite avoiding high-temperature combustion processes, HTP still generates various hazardous VOCs through tobacco pyrolysis, including toxic or carcinogenic carbonyl compounds, unsaturated hydrocarbons, heterocyclic compounds, and sulfides. Their impact on human health and the environment requires further analysis. These findings provide in-depth, isomer-specific insights into our understanding of the exposure risks from HTP smoke and are crucial for guiding future regulation of HTP.

Traditional paper-based materials suffer from low heat transfer efficiency, severely limiting the uniform and efficient generation of aerosols in heated tobacco products (HTPs). This study utilized cellulose nanofibers (CNFs) to surface-activate highly thermally conductive hexagonal boron nitride (BN) and uniformly dispersed it in a paper-based reconstituted tobacco (RT) substrate, successfully constructing a continuous heat transfer network. The composite substrate exhibits excellent out-of-plane thermal conductivity (0.1559 W/(m·K)) and an extremely fast transient thermal response rate (13 °C/s). Distributed activation energy model (DAEM) kinetics further confirmed that this optimized thermal conductivity architecture significantly reduces the apparent mass-loss activation energy during the thermal conversion process. Mass spectrometry results showed that, compared to the control group, the relative EIC peak areas (reflecting the relative release intensities) of glycerol and nicotine increased to 134.50 ± 0.68% and 158.38 ± 0.25%, respectively. More importantly, it achieved exceptionally good puff-by-puff release consistency, reducing the coefficients of variation (CV) of glycerol and nicotine release to 13.7 ± 0.39% and 21.11 ± 0.65%, respectively. Crucially, this work demonstrates a high-value industrial application of crop-derived nanocellulose, highlighting its tremendous potential in engineering advanced, bio-based functional composites for thermal management.

Pyridine edge-functionalized g-C 3 N 4 coordinates with cobalt phthalocyanine, enabling efficient directional electron transfer and significantly boosting visible-light-driven CO 2 photoreduction to CO.

This study addresses key challenges faced by industrial multi-stage winnowing systems in the agricultural processing field when separating flexible filamentous particles and rigid acicular particles. These challenges include complex system structures, strong nonlinearity of gas-solid flow, and difficulties in the synergistic regulation of operational parameters. To overcome the computational efficiency bottleneck of traditional simulation methods at the industrial scale, this study develops a coarse-grained CFD-DEM coupled calculation framework suitable for these two types of heterogeneous particles based on the Energy Minimization Multi-Scale Discrete Particle Method (EMMS-DPM). Results show that the proposed model can effectively quantify the impact of multi-scale particle behaviors on separation efficiency. It also reveals the mechanism that stem stick particles with a thickness of ≥2.0 mm are more likely to be separated due to gravitational sedimentation. Furthermore, by simulating and optimizing the air intake velocity of the primary winnowing, the comprehensive winnowing efficiency is improved by 14.17% within an acceptable error range (the relative error between simulated and experimental values is within 6.0%). This research provides reliable numerical method support and theoretical basis for the parameter optimization and performance upgrading of industrial-scale winnowing systems.

The puff-by-puff release stability of aerosols generated by heated tobacco products (HTPs) is a key factor influencing consumers' sensory experience. This study systematically investigates the effects of different heating modes and the compatibility between heated tobacco product sticks and their Compatible devices on aerosol release stability. By quantifying the puff-by-puff release concentrations of key components in HTPs aerosols, the release stability is comprehensively evaluated via the relative standard deviation (RSD) and relative mean absolute deviation(RMAD). The results show that: (1) Compared with peripheral heating, central heating provides higher puff-by-puff release stability of HTPs aerosols;(2) Under the selected experimental conditions, electromagnetic central heating device exhibits good compatibility with two distinct types of HTPs sticks; (3) After optimizing the heating temperature profile, a resistive central heating device could also be adapted to the two distinct HTPs sticks, ensuring consistent and uniform puff-by-puff aerosol release. Heating modes and compatibility between stick and device are critical determinants of aerosol release stability. These findings offer theoretical and technical support for the optimization and regulation of HTPs systems, thereby helping to effectively enhance consumers' sensory perception.

Dinuclear germylenes 1 and 2 bearing bis(beta-diketiminate) ligands with 1,3-phenylene and 1,2-cyclohexylene linkers, respectively, have been synthesized. The structure flexibility was verified by the variable-temperature NMR analysis. Further salt metathesis with AgOTf led to bis-germylene 3 with OTf substituent. The reaction of 1 with LiAl[OCH(CF3)2]4, aiming to get the dinuclear dication, resulted in the formation of alkoxyl substituted bis-germylene with the elimination of Al[OCH(CF3)2]3. All compounds have been characterized by nuclear magnetic resonance (NMR) and single-crystal X-ray diffraction (SC-XRD).

The thermophysical properties and pyrolysis behavior of reconstituted tobacco (RT) are closely associated with aerosol release in heated tobacco products (HTPs). However, the inherently low thermal conductivity of RT restricts heat transfer and temperature uniformity, thereby limiting the efficient release of key aerosol constituents (KACs). Herein, continuous heat-transfer networks were built into the cellulose fiber matrix via graphenederived thermal pathways. TEMPO-oxidized cellulose nanofibrils (TOCNF), rich in carboxylate groups, were used to stabilize graphene and suppress nanosheet restacking, forming a homogeneous G/TOCNF gel. During wet pulping, cationic guar gum (CGG) served as a positively charged bridge to mediate electrostatic adsorption between the negatively charged G/TOCNF complex and cellulose fibers, enabling uniform graphene retention and stable immobilization. This interfacial regulation produced a thermally conductive substrate (TCS) with a continuous three-dimensional graphene thermal pathway. RT-5 with 5.03 wt% graphene achieved a thermal conductivity of 0.3168 W/m & sdot;K, a 52% increase over RT-0. Owing to enhanced thermal transport, the KACs release rate increased from 57.52% to 63.13%. TG/DTG analysis revealed graphene-mediated thermal regulation and composition-dependent mass-loss redistribution, reflected by shifted decomposition peaks and a reduced high-temperature mass-loss rate from -0.426% to - 0.342%/degrees C. Kinetic analysis showed that the mean activation energy increased from 199.44 to 376.54 kJ/mol and from 203.38 to 388.92 kJ/mol by the FWO and KAS methods, respectively, indicating elevated pyrolysis barriers and regulated decomposition kinetics. Overall, the G/TOCNF-CGG system improves thermal management, KAC release, and pyrolysis regulation for next-generation HTP functional base materials.

Electrically heated tobacco products (eHTPs) are designed to reduce harmful and potentially harmful constituent (HPHC) emissions compared to conventional cigarettes by operating below tobacco combustion thresholds. However, the temperature-dependent release mechanisms of HPHCs under different heating modes remain poorly characterized. The thermal release dynamics of 16 priority HPHCs (e.g., CO, NO, aldehydes, TSNAs, VOCs) in eHTP aerosols generated by central and peripheral heating modes were investigated. The results revealed a critical temperature range (275-300 degrees C for peripheral heating mode; 325-350 degrees C for central heating mode), beyond which HPHC emissions increase due to intensified pyrolysis. Notably, peripheral heating exhibits higher heating uniformity, leading to 2.5-5.8-fold higher HPHC yields than central heating at equivalent temperatures. Multivariate clustering analysis further identifies distinct emission patterns: stepwise increases under central heating versus abrupt surges under peripheral heating. These findings establish quantitative temperature-emission relationships and provide actionable guidelines for optimizing eHTP designs to minimize toxicant release while maintaining nicotine delivery.

The electrocatalytic nitrate reduction reaction (NO3-RR) to ammonia is a promising approach for converting nitrate pollutants to ammonia under mild conditions. Metal phthalocyanine-based conjugated polymers, with their well-defined structures and tunable functionality, are emerging as efficient two-dimensional (2D) catalysts for this reaction. Herein, we report a 2D-conjugated nickel phthalocyanine polymer (NiPcP) that demonstrates high efficiency and selectivity in the NO3-RR. The material features high-density, well-defined Ni-N4 sites and the nitrogen-bridged tetra-isoindole structures create a hydrophobic microenvironment and electron-rich Ni centers, which facilitate nitrate adsorption and electron transfer and suppress the hydrogen evolution reaction (HER). As a result, the NiPcP achieves a maximum faradaic efficiency of 99.7% and an NH3 yield rate of 14.2 g h-1 gcat-1, maintaining over 80% efficiency across a broad potential window (from -0.5 to -0.9 V vs. RHE) and a wide nitrate concentration range (from 10.0 mmol L-1 to 2.0 mol L-1). It is the first noble metal-free Ni-based catalyst that exhibits such a high FE in such a broad potential window and wide nitrate concentration range simultaneously. This work offers an effective molecular design strategy for developing metal-organic electrocatalysts for sustainable ammonia synthesis and nitrate pollution remediation.

Hybrid electrocatalysts combining noble metals with tailored supports are crucial for efficient hydrogen evolution reaction (HER) across a wide pH range. Here, we report a ruthenium cluster catalyst anchored on molybdenum boride support engineered with boron vacancies (Ru/MoB-BV) for highly efficient HER. The introduced boron vacancies optimize the electronic interactions between molybdenum boride and the Ru cluster via a Ru─Mo electron bridge, leading to enhanced catalytic performance and stability. Combined electrochemical analysis and density functional theory calculations reveal that Ru/MoB-BV possesses a favorable water-dissociation energy and optimal desorption energies for hydrogen/hydroxide intermediates on Ru clusters. These merits confer exceptional HER performance, with overpotentials of 40 and 34 mV at 10 mA cm-2 in alkaline freshwater and seawater, respectively; 24 mV in acidic electrolyte; and 67 mV in neutral electrolyte. Importantly, the activated Ru and Mo sites enable an anion exchange membrane electrolyzer employing Ru/MoB-BV as the cathode to exhibit remarkable stability, operating for 100 h at 500 mA cm-2. This work provides insights into the design of highly efficient and stable catalysts through the precise engineering of surface vacancies.

Spontaneous, radical-mediated oxidation of nicotine has been demonstrated to occur at nanometer aerosol interfaces under ambient conditions for the first time. The oxidation products were identified by vacuum ultraviolet photoionization aerosol mass spectrometry, whereas peroxy-radical adducts were detected by electron paramagnetic resonance spectroscopy, providing direct evidence for radical-mediated oxidation at the air-water interface of aerosols. The oxidation was markedly inhibited by sodium chloride and benzoic acid: the former attenuates interfacial electric fields that promote hydroxyl radical generation, whereas the latter forms a stable complex with nicotine, blocking reactive sites for hydrogen abstraction. These findings reveal a previously unrecognized transformation pathway for nicotine, clarifying its degradation under humid respiratory conditions while also uncovering a general interfacial mechanism for spontaneous oxidation of organic species confined in aqueous aerosols.

The thermal conversion characteristics of reconstituted tobacco (RT) are critically linked to the aerosol release in heated tobacco products (HTPs). The low thermal conversion efficiency and undesirable pyrolysis constituents of RT hinder its value in advanced applications. To address this, we developed a multi-coating strategy that introduces an efficient thermal conduction pathway into the RT system. Graphene was homogeneously encapsulated within a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofiber (TOCNF) to form a G/ TOCNF composite, which was then coated onto a fibrous substrate (FS) to fabricate a thermally conductive layer. This functional fibrous material served as a substrate for an aerosol-generating matrix to form the final RT. With a graphene loading of 0.8 wt%, the thermal conductivity of the coated substrate increased by 0.14 W/(m & sdot;K). More importantly, this enhanced thermal management significantly accelerated the pyrolysis kinetics of RT. Thermogravimetric analysis revealed a 19.62% increase in total mass loss and a higher peak mass loss rate for the G/TOCNF-0.8 sample compared to the control. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analysis demonstrated a significant reduction in harmful heterocyclic substances, thereby establishing a predictive framework to evaluate the impact of the modified hydrogel on pyrolytic products. Consequently, the total thermal conversion rate of the G/TOCNF-0.8 RT increased by 11.81% at 260 degrees C. This study confirms that the G/ TOCNF coating not only improves filler dispersion and heat transfer but also effectively enhances the thermal conversion efficiency of aerosol, offering a promising strategy for developing heat-responsive controlled-release systems based on engineered fibrous carriers.

Chlorine evolution reaction (CER) based on RuO2 and IrO2 electrocatalysts is fundamental to the chlor-alkali industry but suffers from slow kinetics and high overpotentials, resulting in substantial energy consumption. Here, we report an ultrafast solvent-free microwave-assisted strategy to synthesize Ru-RuO2 heterojunctions anchored on hard carbon (HC) supports. The HC support affords high electrical conductivity, reducing charge-transfer resistance and structural robustness. Meanwhile, uniform active sites can be well dispersed on the HC under harsh electrochemical conditions. The Ru-RuO2 heterojunction enables synergistic electronic modulation, optimizing chloride ion (Cl-) adsorption and chlorine gas (Cl2) desorption. Furthermore, the active sites can be tuned from well-established oxygen of RuO2 to metallic Ru. Consequently, the Ru-RuO2@HC-1100 catalyst exhibits remarkable CER performance, achieving a low overpotential of 77 mV at 10 mA/cm2 with good stability, surpassing commercial dimensionally stable anode (DSA) catalysts and most previously reported materials. This study presents an effective strategy for synthesizing CER electrocatalysts with low overpotential and enhanced activity.

Ordered intermetallic Pt3Co compounds are highly promising alloy materials for oxygen electrocatalysis, while the sluggish kinetics and high cost of Pt still hinder their wide use in practical applications. In this work, boron atom gap-doped Pt3Co nanoparticles loaded on carbon nanobowls (B-Pt3Co/CNBs) are obtained to enhance the oxygen reduction reaction (ORR) performance. The introduction of B atoms is responsible for the negative shift of the d-band center compared to Pt3Co, and the subsequent reduction process leads to the uniform loading of B-Pt3Co nanoparticles on hollow carbon nanobowls. It is demonstrated that B-Pt3Co/CNBs exhibit the best electrocatalytic performance for ORR with an onset potential of 1.095 V versus RHE and a half-wave potential of 0.985 versus RHE, as well as robust electrocatalytic stability with negligible activity decay even after 50 000 cycles. Experimental and theoretical calculations show that the introduction of the highly electronegative metalloid B leads the Pt atoms to lose electrons, which changes the electronic structure of Pt3Co that can weaken the bonding strength of Pt-O and accelerate the protonation and desorption of O* on the surface of the B-Pt3Co/ CNB, reducing the energy barrier of the rate-determining step during the ORR process.

Heated-not-burned cigarette is a new type of tobacco that has arisen in recent years, the oxidative pyrolysis characteristics of which at low temperature is one of the key factors related to its smoke releasing and taste. In this paper, components separation was used for the first time to obtain the components of cherry-red tobacco, which are as water-soluble matter, WM; ethanol-soluble matter, EM and residue solid matter, RM. Then a study about weight loss, heat loss, pyrolysis fraction and char products was carried out on the low-temperature oxidative pyrolysis process of cherry-red tobacco and its components. The results were compared with those obtained under inert atmosphere to analyze their oxidative pyrolysis characteristics. The results showed that, condensable furans and nicotine pyrolyzed from WM, EM and Raw in low-temperature oxygen decreased by half than that in inert atmosphere, while CO and CO2 were more than 20 % higher. Raw cherry-red tobacco and its components showed a trend of pseudo weight-gain, indicating the occurrence of oxygen adsorption. During the low-temperature oxidative pyrolysis process, oxidation and pyrolysis reactions process in parallel, and WM and EM exhibited a reaction mechanism dominated by alternating oxidation and decomposition. In addition, a synergistic effect was found among the components during the low-temperature oxidative pyrolysis process of the cherry-red tobacco.

Isoconversional kinetic analysis of a chemical reaction can effectively evaluate the activation energies, but it cannot directly determine the kinetic mechanism function (KMF). This study focuses on the complementary use of the Friedman isoconversional method and modified empirical KMF to investigate the kinetics of tobacco waste pyrolysis. The systematical analysis of the modified empirical KMF shows its abundant flexibility in describing various complex kinetics, as evidenced by diverse shape characteristics of kinetic curves. The kinetic results of tobacco waste pyrolysis were obtained by the integrated approach of the Friedman isoconversional method and modified empirical KMF: activation energies ranging from 176.3 to 352.5 kJ & sdot;mol-1 in the alpha range between 0.05 and 0.95 and the KMF for tobacco waste pyrolysis being f(alpha) = alpha- 1.8931 & sdot;(1-1.0206 & sdot;alpha)5.9108.The combination of the Friedman isoconversional method with the modified empirical KMF serves as an effective method for conducting the comprehensive kinetic analysis of lignocellulosic biomass pyrolysis. The results can be used to establish the comprehensive and accurate chemical model, which is helpful for accurate numerical simulation of the biomass pyrolysis process, enabling the optimization of pyrolysis reactor configurations and operation conditions based on the numerical simulation results, thereby facilitating the industrial application of tobacco waste conversion.

To enhance the charge separation efficiency of g-C3N4 and facilitate electron transfer between photosensitizer and molecular catalyst, polarization and coordination strategies are used by grafting pyridine rings onto the edge of the g-C3N4 framework. Herein, electron-withdrawing pyridine edge-functionalized g-C3N4 (g-C3N4-Px) was synthesized via facile one-step thermal polymerization of urea and 4-aminopyridine, and employed as visible-light photosensitizer hybridized with cobalt phthalocyanine (CoPc) for efficient photoreduction of CO2. Both experimental and theoretical results confirm that electron-withdrawing pyridine grafting facilitates in-plane charge separation and directs electron migration toward the edge of g-C3N4, narrows its band gap for enhanced visible-light absorption, and provides dynamic coordination sites that significantly boost interfacial electron transfer from g-C3N4-Px to CoPc. A significant increase in the CO yield was achieved with the optimized CoPc/g-C3N4-P1.5 hybrid, reaching 14.95 mmol g-1 after 6 hours of visible-light irradiation-a 6.1-fold improvement over the unmodified CoPc/g-C3N4 (2.47 mmol g-1). This work provides a facile approach for developing highly efficient hybrid photocatalysts for CO2 reduction and improving the charge separation and visible-light absorption in organic semiconductors.Keywords: CO2 photoreduction; Cobalt phthalocyanine/g-C3N4 hybrid photocatalysts; Polarization engineering; Directional electron transfer; Coordination interaction; Electron-withdrawing effect.