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Conventional surface acoustic wave (SAW) acoustic tweezers limit their flexible availability and sustainability due to the permanent attachment of all components, such as the introduction of biological cross-contamination when reusing directly bonded microchambers, and the increased cost of changing the microfabricated electrode pattern on the relatively expensive and fragile LiNbO3 (LN) surface when changing the bioanalysis target. To address these problems, we proposed a plug-and-play fully detachable SAW acoustic tweezers (FDSAs) platform comprising a pair of detachable and replaceable flexible electrode plates and polydimethylsiloxane (PDMS) microchamber, which enables efficient and fast multiscale range particle manipulation. To expand the practicality of FDSA toward high-throughput acoustofluidics in a large-area microchamber, an arrayed micropillar structural support is designed to prevent the microchamber from collapsing and demonstrating no effect on the manipulation performance in the modified acoustic waves field. Overall, such FDSA retains the advantages of traditional acoustic tweezers, simplifies the processing and cost for diversified device design demands, and further facilitates subsequent biochemical analyses.

Flavin adenine dinucleotide (FAD), serving as a light-absorbing coenzyme factor, can undergo conformationally isomeric complexation within different enzymes to form various enzyme–coenzyme complexes, which exhibit photocatalytic functions that play a crucial role in physiological processes. Constructing an artificial photofunctional system using FAD or its derivatives can not only develop biocompatible photocatalytic systems with excellent activities but also further enhance our understanding of the role of FAD in biological systems. Here, we demonstrate a supramolecular approach for constructing an artificial enzyme–coenzyme-type host–guest complex with photoinduced catalytic function in water. First, we have designed and synthesized a water-soluble tetraphenylethene (TPE)-based octacationic molecular cage (1) with a large and flexible cavity, which can adaptively encapsulate with two FAD molecules with “U-shaped” conformation (uFAD) to form a 1:2 host–guest complex (1⊃uFAD2) in water. Second, based on the conformationally isomeric complexation of FAD within 1, the 1⊃uFAD2complex facilitates electron and energy transfers to molecular oxygen upon the white-light illumination, efficiently producing reactive oxygen species (ROS) such as superoxide radical (O2•–) and singlet oxygen (1O2). To our knowledge, the 1⊃uFAD2complex acts as a photocatalyst to achieve the highest turnover frequency (TOF) of 35.6 min–1for the photocatalytic oxidation reaction of NADH via a photoinduced superoxide radical catalysis mechanism in an aqueous medium. At last, combining the cytotoxic effects of ROS and the disruption of the intracellular redox balance involving NADH, 1⊃uFAD2as a supramolecular photosensitizer displays an excellent oxygen-independent photocatalysis-assisted photodynamic therapy in hypoxic tumors.

Purpose: Project-based learning is one of the most effective methods of transferring academic knowledge and skills to real-world situations in higher education. However, its effectiveness is not much investigated focusing on the students' narrative. This study aims at evaluating the students' experience and perspective on adopting project-based learning in master by research and doctoral programmes for proactive skills development. Design/methodology/approach: This study evaluates the self-reflection of 10 postgraduate students and their supervisor who have participated in developing a software tool for solar photovoltaics (PV) integrated building envelope design, management and the related education. Findings: Findings reveal that the students have effectively improved their knowledge on the subject via collaborating with the industry, self-learning/observation, peer learning, problem-solving and teamwork. Dividing the project into student-led tasks has improved the decision-making and leadership skills, risks identification, planning and time management skills. The overall experience has (1) built up confidence in students, (2) enhanced their creativity and critical thinking and (3) improved their proactive skills and context knowledge. Originality/value: A clear research gap can be seen in exploring the effectiveness of project-based learning for master by research and doctoral programmes, which mainly focus on extensive research. These programmes do not necessarily focus on developing students' proactive skills, which is the main requirement if they intend to work in the construction industry. This paper addresses the above research gap by demonstrating the effectiveness of project-based learning for developing the proactive skills in a research-intensive learning environment.

Numerous studies highlight the significance of biomimetic metallic implant surfaces for enhancing osseointegration through synergistic regulation of osteogenesis-angiogenesis. However, achieving clinical demands through singular structural or compositional biomimicry poses challenges. Therefore, the integration of both structural and compositional biomimicry, to closely emulate the host bone surface, is crucial for maximizing the biological activity of metallic implants. We synthesized a micro/nano hierarchical SrSi-codoped hydroxyapatite coating on Zr16Nb12Ti alloy through a simple microarc oxidation-hydrothermal reaction. Results revealed that Si doping enhances hydroxyapatite (HA) growth along the c-axis, forming large-sized nanorods. However, co-doping of Sr and Si inhibits grain growth by reducing crystal growth freedom, yielding a finer HA nanowire coating (MH-SrSi). MH-SrSi exhibits outstanding hydrophilicity attributed to the finer HA nanowires on the coating surface, promoting the adhesion of proteins and cells. Additionally, the released Sr and Si from MH-SrSi stimulate the secretion of osteogenesis-related proteins in osteoblasts and angiogenesis-related factors in endothelial cells, exhibiting a synergistic effect on promoting osteogenesis and angiogenesis. In vivo evaluation mirrors these results and shows that the micro/nano hierarchical structures of MH-SrSi elicited inward bone growth. Overall, MH-SrSi, combining structural biomimicry and compositional biomimicry, exhibits excellent osseointegration capability, making it a promising candidate for implant materials.

In this study, we presented an investigation into a newly developed metastable Zr–10Nb–6Sn alloy meticulously tailored to fulfill the demanding requisites of magnetic resonance imaging (MRI)-compatible hard implants. The effect of cold rolling reduction (0%, 10%, 20% and 40%) on the mechanical properties and magnetic susceptibility of the alloy has been systematically studied. With the increase of cold rolling reduction, the yield strength and tensile strength of the alloy increase, while the elastic modulus decreases first and then increases slightly. The sample with 40% cold rolling (CR40%) exhibits excellent matching of yield strength ∼ 905 MPa and elastic modulus ∼55.8 GPa, with a superior yield strength-to-elastic modulus ratio than that of other reported metallic biomedical materials. The deformation mechanism of Zr–10Nb–6Sn alloy during cold rolling includes stress-induced α" phase, kink bands and dislocation slip. Due to the addition of Sn element with low magnetic susceptibility (0.03× 10−6cm3g−1) and the formation of ω phase, the solution-treated sample (CR0%) has a low magnetic susceptibility ∼ 0.77 × 10−6cm3g−1, which is significantly lower than that of other reported titanium and zirconium based biomedical alloys. The magnetic susceptibility of the samples increases from 0.77× 10−6cm3g−1to 1.35 × 10−6cm3g−1as the cold rolling reduction increases, which may be attributed to the decrease in ω-phase content and the increase in α''-phase content during cold rolling. Hence, the cold-workable Zr–10Nb–6Sn alloy, exhibiting exceptional mechanical compatibility and low magnetic susceptibility, holds promise as a potential alloy for MRI-compatible hard tissue replacements.

Image is one of the most important forms of information expression in multimedia. It is the key factor to determine the visual effect of multimedia software. As an image restoration task, image deraining can effectively restore the original information of the image, which is conducive to the downstream task. In recent years, with the development of deep learning technology, CNN and Transformer structures have shone brightly in computer vision. In this paper, we summarize the key to success of these structures in the past, and on this basis, we introduce the concept of a layer aggregation mechanism to describe how to reuse the information of the previous layer to better extract the features of the current layer. Based on this layer aggregation mechanism, we build the rain removal network called DenseformerNet. Our network strengthens feature promotion and encourages feature reuse, allowing better information and gradient flow. Through a large number of experiments, we prove that our model is efficient and effective, and expect to bring some illumination to the future rain removal network.

Due to their diverse functional groups and structural composition, carbon-based catalysts exhibit superior performance in various catalytic reaction systems, such as hydrogenolysis, hydrogenation, and oxidation. Herein, we propose an effective strategy of lignin liquid-phase depolymerization by applying the designed lignin-based carbon catalysts to produce aromatic chemicals. A series of Ni–Mo bimetallic carbon-based catalysts were synthesized to explore the effect of different preparation methods on the catalytic activity. The results demonstrate that the embedded Ni–Mo/C-WMOcatalyst with multi-active sites of Ni, MoO3, and Mo2C results in a prominent catalytic effect on lignin depolymerization. The Ni–Mo/C-WMOcatalyst can achieve a lignin conversion of 87.62% with a 42.25% monophenol yield in the methanol and water system. With the synergistic contribution of multiple active sites of the catalyst and the mixed-solvent system (water, methanol, and 1, 4-dioxane), a remarkably high yield of 62.95% of mono-phenolic compound was achieved at 260 °C and 3 MPa N2with a reaction time of 4 h. The selectivity of 2-methoxy-4-methylphenol and 2-methoxy-4-ethylphenol in liquid products was 40.85 and 36.42%, respectively. Vanillin, a typical product from lignin depolymerization reported in the literature, was further degraded to monophenol in this system. The outcomes also confirmed that the in situ hydrogen production system of methanol and water coupled with 1,4-dioxane facilitated the lignin depolymerization significantly.

This paper proposes a nine-level switched-capacitor step-up inverter (9LSUI) which can achieve a quadruple voltage gain with single dc source. Differing from other switched-capacitor inverters, the voltage stress of switches is effectively reduced due to the elimination of H-bridge, and the peak inverse voltage of all switches is kept within 2Vdc. In addition, the proposed inverter is able to integrate inductive load, and the capacitor voltage self-balancing can be achieved without any auxiliary circuits. Moreover, the topology structure can be flexibly extended to raise the output levels, and the peak inverse voltage of switches can remain constant with the increase of sub-modules in the extended structure. Comprehensive comparisons are performed to verify the outstanding advantages of the proposed inverter. Finally, the steady-state and dynamic performance of the proposed inverter is validated through an experimental prototype, and the experimental results are provided to prove the theoretical analysis.

In this Letter, we propose a non-iterative multifold strip segmentation phase method for a spatial light modulator (SLM) to generate multifocal spots of diverse beams (Airy, spiral, perfect vortex, and Bessel–Gaussian beams) in a high-numerical-aperture system, with up to 6D controllability. The method is further validated by an inverted fluorescence microscope. By adjusting the bright and dark voltage parameters of the SLM, zero-order light caused by the pixelation effect of the SLM has been successfully eliminated. We hope this research provides a more flexible and powerful approach for the rapid modulation of multi-focus light fields in the development of biomedicine and lithography.

The interactions of DNA molecules and metal ions lead to changes in their configuration and conformation, which in turn influence the current characteristics of the solution as DNA molecules are translocated through a micro/nanofluidic channel and ultimately cause serious impacts on the practical applications of DNA/gene chips for precisely manipulating and studying the molecular properties of single DNA molecules. In this study, the current characteristics of λ-DNA solutions without or with metal ions (i.e., K+, Na+, Mg2+, and Ca2+) were experimentally investigated when they were transported through a 5 μm microcapillary under an external electric field with asymmetric electrodes. Experimental data indicated some meaningful results. First, the current–voltage relations of the metal ion solutions were all linear, while those of λ-DNA solutions without or with metal ions were all nonlinear and followed power functions, of which the indices were related to the type, valence, and mobility of ions. Furthermore, as the concentrations of metal ions increased, the power indices of the λ-DNA solutions with monovalent metal ions increased, while those of the λ-DNA solutions with divalent ions decreased. Finally, the main reasons for the current characteristics were theoretically attributed to two possible mechanisms: the polarizations on the asymmetric electrodes and the interactions between λ-DNA and metal ions. These findings are helpful for the design of new biomedical micro/nanofluidic sensors and labs on a chip for accurately manipulating single DNA molecules.

Catalytic fast pyrolysis (CFP) of biomass is a promising technology that can convert biomass into fuels. To understand how the metal oxides modified HZSM-5 catalysts enhance the formation of desirable hydrocarbons as well as suppress the coke formation during catalytic pyrolysis of lignocellulosic biomass, three types of metal (molybdenum (Mo), gallium (Ga), and tungsten (W)) oxides modified HZSM-5 catalysts were prepared. The activity of the catalysts was evaluated on a micro-reactor system. The effects of the atmosphere, metal oxide types, loading amounts of metal oxide, and catalysis temperature were all discussed. The introduction of hydrogen significantly enhanced the formation of hydrocarbons and decreased the coke formation. The yield of aliphatic products was further increased by 60%, while coke formation was suppressed by 52% using metal oxide-modified HZSM-5. Among these catalysts, HZSM-5 modified by molybdenum oxide obtained the highest hydrocarbon yield of 49.6%. HZSM-5 modified by gallium oxide obtained the highest aliphatic hydrocarbon yield of 30.4%. Compared to the control test using the HZSM-5 catalyst, coke yields were also decreased by 36%, 38%, and 35% for HZSM-5 modified by molybdenum oxide, gallium oxide, and tungsten oxide, respectively. HZSM-5 modified by molybdenum oxide was selected to further investigate the effects of loading amounts, catalysis temperature, and biomass to catalysts ratio.

Computational ghost imaging or single-pixel imaging enables the image formation of an unknown scene using a lens-free photodetector. In this Letter, we present a computational panoramic ghost imaging system that can achieve a full-color panorama using a single-pixel photodetector, where a convex mirror performs the optical transformation of the engineered Hadamard-based circular illumination pattern from unidirectionally to omnidirectionally. To our best knowledge, it is the first time to propose the concept of ghost panoramas and realize preliminary experimentations. It is foreseeable that ghost panoramas will have more advantages in imaging and detection in many extreme conditions (e.g., scattering/turbulence and unconventional spectra), as well as broad application prospects.

The aim of this study was to clarify the dose- and time-dependent effect of the γ-secretase inhibitor (DAPT) combined with cisplatin on osteosarcoma (OS) cells, evaluated by confocal Raman microspectral imaging (CRMI) technology. The intracellular composition significantly changed after combined drug action compared with the sole cisplatin treatment, proving the synergistic effect of DAPT combined with cisplatin on OS cells. The principal component analysis-linear discriminant analysis revealed the main compositional variations by distinguishing spectral characteristics. K-means cluster and univariate imaging were used to visualize the changes in subcellular morphology and biochemical distribution. The results showed that the increase of the DAPT dose and cisplatin treatment time in the combination treatment induced the division of the nucleus in OS cells, and other organelles also showed significant physiological changes compared with the effect of sole cisplatin treatment. After understanding the cellular response to the combined drug treatment at a molecular level, the achieved results provide an experimental fact for developing suitable individualized tumor treatment protocols.

A ZnO/ZnCl2composite with stable 3D structural morphologies and long lasting superhydrophilicity was synthesized on the top surface of a nano porous anodic alumina (nanoPAA) substrate. The wettability of a nanoPAA-ZnO/ZnCl2was systematically characterized and the experimental data indicated that the water contact angle (WCA) of 0° could be achieved as well as maintained over 7 days and still remained at 4.36° after 50 days, and its 3D structural morphology had no clearly observable change during this period. The mechanism for the superhydrophilicity of the composites was interpreted in terms of the inherent hydrophilicity of ZnO/ZnCl2nanofilm, the three-dimensional structures of wrinkled nanoflakes, the nanogaps between neighbor nanoflakes, the difference of structual morphologies (i.e., size, shape, and upright posture of nanoflakes), and the measured True Volume of voids in the nanocomposite. The structural morphologies were mainly determined by the parameters such as the original concentration of precursor ZnCl2and the pore diameter of nanoPAA substrate. The study proposes a promising superhydrophilic nanomaterial and a cost-effective synthesis method, which will play a practical role in the fields of biomedical molecular sensors and micro/nanofluidic chips.

Pyrolysis has created many (and will open more) possibilities for high-value utilization of biomass. To obtain the optimal amount of desired pyrolysis products, especially high-quality bio-oil, a great deal of effort has been conducted in both academia in the past few decades, to clarify fundamental mechanisms of biomass pyrolysis and design efficient relevant technical processes. This paper comprehensively reviews recent advances in both fundamental studies and technology applications of biomass pyrolysis. First, pyrolysis mechanisms of real biomass and its major components, the reactor-scale simulation of biomass pyrolysis, and applications of pyrolysis products are discussed. Then, according to the requirements imposed to improve the physicochemical properties of respective pyrolysis products, relevant optimization and regulation methods for biomass pyrolysis process are reviewed. Previous research has indicated that biomass copyrolysis with other feedstock can not only enhance physicochemical properties of pyrolysis products but also effectively realize recycling of wastes. Thus, an in-depth discussion of recent advances in biomass copyrolysis with four different feedstocks (i.e., coal, plastics, tires, and sludge) is covered in this Review. As an indispensable component of general biomass pyrolysis, recent activities of catalytic biomass pyrolysis are also summarized, including new catalytic pyrolysis processes such as catalytic hydropyrolysis and catalytic copyrolysis. Besides, two novel heating approaches (microwave heating and solar heating) for biomass pyrolysis are described, and their features are compared with the conventional heating method. Finally, this Review is concluded with perspectives for future directions of biomass pyrolysis.

Reactive catalytic fast pyrolysis (RCFP) of biomass with atmospheric pressure hydrogen is a promising route for the deoxygenation of biomass pyrolysis vapors while retaining high carbon yields in the bio-crude. RCFP process development was accomplished in a bench-scale bubbling fluidized-bed reactor with in situ catalyst configuration. Results are presented that highlight the impact of temperature, biomass weight hourly space velocity (WHSV), reaction pressure, and time on stream on the hydrodeoxygenation of different oxygen-containing species produced during biomass reactive catalytic fast pyrolysis to improve the bio-crude product yield and quality. The highest bio-crude and C4+hydrocarbons yield was 46.5 wt % on a carbon basis. The optimal temperature range for RCFP is 450–475 °C; the biomass WHSV should be kept low, around 0.6 h–1in this reactor system, to produce a low oxygen content bio-crude (7.2 wt %), and improvements in the bio-crude yield and quality based on increased pressure are less significant beyond 2.7 bar. The product composition varies by at most 10% for up to 3.5 h’ time on stream (biomass-to-catalyst ratio of 2.6 g g–1), indicating a stable catalyst activity for hydrodeoxygenation.

Nitrogen-doped hierarchical porous biochar has aroused great interest in energy storage and adsorption applications. In this study, nitrogen-doped hierarchical porous biochar was prepared from corn stalks by in situpyrolysis with urea as the nitrogen source and NaHCO3as the green activation agent. The liquid adsorption behavior of biochar was evaluated using phenol as a pollutant probe. The results showed that urea had a synergistic effect on the pore structure development of biochar in the presence of an activation agent. The addition of urea especially promoted the formation of micropores. X-ray photoelectron spectroscopy results showed that nitrogen atoms were successfully introduced into the skeleton of biochar in the form of different nitrogen species, which promote the adsorption of phenol. The phenol adsorption was dominated by micropore filling, and the adsorption capacity was positively correlated with the content of graphitic N. The nitrogen-doped biochar obtained at 700 °C with a moderate surface area and a high content of graphite type N exhibited the highest adsorption capacity of phenol. The kinetic analysis also indicates the existence of chemical interactions in the adsorption process.

Probing depth and system aberrations have direct impacts on the spatial resolution of stimulated emission depletion (STED) microscopes. Based on the vectorial diffraction theory, the influence of coma and astigmatism on the focal patterns of STED microscopes in probing stratified mediums with discontinuous refractive indices (e.g., glass cover slip, solution, and biological samples, etc.) have been illustrated in detail. The spatial resolution of the STED system has been discussed by analyzing the full width at half-maximum size of the fluorescence spots. It is found that, while probing in stratified media with discontinuous refractive indices, the spatial resolution of a STED microscope can be very sensitive to the existence of aberrations, e.g., coma and astigmatism, at different probing depths, as a result of mismatched axial positions of the excitation and depletion patterns. The spatial resolution of STED can be degraded up to 1.87- and 1.95-fold compared to that without aberrations. Therefore, a careful evaluation of the influence of aberration and discontinuous refractive indices should be taken into account when applying a STED microscope to realize super-resolution images.

Rotary kiln is widely used for thermal disposal of solid waste due to its effectiveness and high efficiency in recent years. To further improve the processing efficiency, a newly designed rotary kiln with three-section structure is proposed, and the behaviours of particle motion and heat transfer are investigated. Firstly, a lab-scale rotary kiln is manufactured, and experiments are carried out. Verified by experimental data, a CFD-DEM numerical model is developed to analyze the particle motion and heat transfer characteristics with the effects of inlet flue gas temperature, feeding rate and rotating speed. The results show that the outlet temperature increases linearly with the flue gas temperature, while it is negatively correlated with the feeding rate and rotating speed. In addition, the volumetric heat transfer coefficient in this complex rotary kiln is analyzed, the overall heat transfer coefficient is between 200 and 700 W/(m3K).

Dark-field microscopy directly detects scattered light from a sample, and therefore requires no fluorescent labeling for single molecule detection. The technique has been extensively used for spectral characterization of nanoscopic particles, but its sensitivity to variations in molecular density has not been explored. 3D chromosome topology plays important roles in regulating life processes. Physical characteristics of DNA (e.g.persistence length) and its interaction with numerous proteins and polyamines determine chromosome and chromatin 3D topology. We herein demonstrate the capacity of dark-field microscopy in real-time monitoring of single DNA molecules' conformation and dynamics. Without fluorescent staining, DNA molecules remain intact in physical characteristics like persistence length, net charges and width of the chain. Exclusion of photobleaching and photocleavage effects allows long-term imaging of bare DNA chains at high ionic strength, in shear flows and in the presence of condensing and stretching agents. Furthermore, our studies reveal that the brightness of single molecules during dark-field imaging is determined by DNA conformation, dark when being stretched and bright upon condensation. The sensitivity of dark-field microscopy to nonuniform distribution of molecular density allows us to study the dynamic activities of the transcriptional factor within the cell membrane. In contrast to a fluorescently tagged antibody, which binds to a specific signaling pathway, variations in molecular density across the nuclear envelope can better represent cellular responses upon stimulation.

Abnormal rheological phenomena arising in Tris-borate–ethylenediaminetetraacetic acid solutions (believed to be Newtonian fluids) were observed in direct current electroosmotic flows within a nanocapillary with a diameter of 200 nm under a low electric field of tens of volts per meter. In solutions with different concentrations and pH values, the flow behavior indices of the power-law fluids were calculated on the basis of current–voltage relations. When the electric field intensity was below a critical value of 6.7 V/m, the fluids exhibited dilatant (shear thickening) effects. Fluid viscosity changed with electric field intensity because the near-wall shear rate of an electroosmotic flow changes with electric field intensity via a power-law relation. When the electric field intensity surpasses the critical electric field, the fluid again becomes Newtonian and has constant viscosity. The investigation shows that in nanocapillaries, fluids commonly believed to be Newtonian can become non-Newtonian near walls as a result of strong nanoscale interfacial effects. The results can also improve our understanding of electroosmosis-related transport phenomena in nanofluidics and biomedical science.

When a GC/MS system is coupled with a pressurized reactor, the separation efficiency and the retention time are directly affected by the reactor pressure. To keep the GC column flow rate constant irrespective of the reaction pressure, a restrictor capillary tube and an open split interface are attached between the GC injection port and the head of a GC separation column. The capability of the attached modules is demonstrated for the on-line GC/MS analysis of catalytic reaction products of a bio-oil model sample (guaiacol), produced under a pressure of 1 to 3 MPa.

At RTI, we are developing a catalytic fast pyrolysis process with a new solid acid catalyst, the performance of which has been evaluated in a pilot‐scale reactor using loblolly pine. More robust technology development requires a deeper understanding of the influence of the feedstock properties of process performance defined by the organic liquid yield and composition. Seven types of woody and herbaceous biomass were tested in a 2.54 cm diameter fluidized‐bed reactor. This study shows that the product distribution and biocrude composition vary widely with different feedstocks. The yield of organic biocrude is in the range of 14.0–20.8 wt % for the tested feedstocks. The yields of incondensable gases and carbonaceous solids vary significantly from feedstock to feedstock, which may be because of the variation of the ash content in the feedstock. A feedstock with a higher ash content generates more gases; specifically more CO2but not necessarily more CO. The chemical composition, which includes lignin, hemicellulose, and cellulose, also affects the biocrude composition and the yield of gases. We also demonstrated a positive correlation between the cellulose content and CO yield and a negative correlation between the hemicellulose content and CO yield. The type of feedstock does matter: It is not clear how the feedstock variety affects the catalytic biomass pyrolysis process under development at RTI. In this study, product yields and distributions from seven types of biomass with distinct compositions are investigated. Both the inorganic and organic compositions of the feedstocks are correlated with the product distribution and biocrude quality for the catalytic pyrolysis process.

Catalytic hydropyrolysis of loblolly pine was studied in a high-pressure fluidized bed reactor using a NiMo hydrotreating catalyst. Hydropyrolysis temperature (375–475 °C) influenced the product distribution, product composition, H2consumption, and process carbon efficiency. The material balances ranged from 84% to 106% with an average of 91%. The organic liquid yields including C4–C6gases ranged from 20 wt % to 24 wt %, and the gas yields were between 11 and 27 wt %. The yield of the solids varied from 8 wt % to 26 wt %. Catalyst stability was studied at 450 °C and 20.68 bar (300 psig) total pressure with 40 vol % H2for 10 days. The organic liquid product yield (22.5 ± 1.35 wt %) and quality (2.8 ± 1 wt % O) were consistent over 10 days of experiments with the same catalyst exposed to daily hydropyrolysis, regeneration, and reduction cycles indicating stable and steady-state catalyst performance over this time period.

In-situ catalytic fast pyrolysis (CFP) is considered to be a promising pathway to produce aromatic hydrocarbons from lignocellulosic biomass. However, the presence of variable amounts of inorganic ash in biomass in the form of alkali and alkaline earth metals (AAEMs) is a concern while using in situ catalysts because AAEMs could influence product distribution from CFP while also being a major reason for catalyst deactivation. In this study, the effect of four alkali and alkaline earth metals (K, Na, Mg, and Ca) commonly found in biomass was investigated to understand their individual influence on the fate of primary pyrolysis products as well as their effect on the selectivity of products from in situ CFP using ZSM-5 catalyst. Experiments were performed in a microreactor (Py-GC/MS) with ZSM-5 catalyst using AAEM-impregnated biomass. It was found that the type of AAEM as well as the concentration were significant, with Mg appearing to be relatively inert when compared to the stronger catalytic activity of K, Na, and Ca. The influence of AAEMs on the formation of pyrolysis products from cellulose, hemicellulose, lignin, and its subsequent influence on CFP is discussed. From noncatalytic pyrolysis experiments, even the lowest concentration of AAEMs (0.1 wt %) was observed to have a significant influence on the thermal decomposition behavior of biomass, promoting the formation of lower molecular weight cellulose and lignin-derived products. AAEMs were found to be influencing CFP product distribution by reducing the carbon yield of desired aromatic hydrocarbons and olefins, while it accelerated pathways resulting in increased yields of thermally derived char and noncondensable gases. The effect of AAEMs on CFP followed the order: Na > K > Ca > Mg.

Fire smoke, which consists large amounts of fine particles, is considered as the fatal factor in fires. In this study, a fast smoke particle elimination method based on electro-acoustic coupling agglomeration technology is proposed. First, the experimental results show that the electro-acoustic coupling agglomeration has higher smoke elimination efficiency compared to single-field. The smoke transmission is much less than 80% after 30 s of single acoustic or electric field action, while the coupled field reaches 90%. Then, the effects of acoustic frequency, sound pressure level and voltage on the smoke elimination characteristics are discussed. It is found that the optimal acoustic frequency is 1.5 kHz. While as the sound pressure level and voltage increase, the elimination efficiency first increases and then tends to stabilize, the critical values of the sound pressure level and voltage are 135 dB and 7 kV. This indicates that there is an optimal combination of the three variables. Finally, through the theoretical analysis of particle movement and the micro-morphology of agglomerates, the particle agglomeration mechanism under the electro-acoustic coupling is analyzed. This study provides a new idea for the fast elimination of fire smoke particle.