Investigation on mechanical properties regulation of rock-like specimens based on 3D printing and similarity quantification

3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properties of 3D-printed specimens to make them proportionally similar to natural rocks.This study investigates mechanical properties of 3D-printed rock analogues prepared by furan resin-bonded silica sand particles.The mechanical property regulation of 3D-printed specimens is realized through quantifying its similarity to sandstone,so that analogous deformation characteristics and failure mode are acquired.Considering similarity conversion,uniaxial compressive strength,cohesion and stress–strain relationship curve of 3D-printed specimen are similar to those of sandstone.In the study ranges,the strength of 3D-printed specimen is positively correlated with the additive content,negatively correlated with the sand particle size,and first increases then decreases with the increase of curing temperature.The regulation scheme with optimal similarity quantification index,that is the sand type of 70/140,additive content of 2.5‰and curing temperature of 81.6℃,is determined for preparing 3D-printed sandstone analogues and models.The effectiveness of mechanical property regulation is proved through uniaxial compression contrast tests.This study provides a reference for preparing rock-like specimens and engineering models using 3D printing technology.

Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance

Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.

Atomic-resolution Interfacial Microstructure and Thermo-electro-magnetic Energy Conversion Performance of Gd/Bi_(0.5)Sb_(1.5)Te_(3)Composites

Thermo-electro-magnetic materials with simultaneously large magnetocaloric(MC)and thermoelectric(TE)effects are the core part for designing TE/MC all-solid-state cooling devices.Compositing MC phase with TE material is an effective approach.However,the elemental diffusion and chemical reaction occurring at the two-phase interfaces could significantly impair the cooling performance.Herein,Gd/Bi_(0.5)Sb_(1.5)Te_(3)(Gd/BST)composites were prepared by a low-temperature high-pressure spark plasma sintering method with an aim to control the extent of interfacial reaction.The reaction of Gd with the diffusive Te and the formation of GdTe nanocrystals were identified at the Gd/BST interfaces by the atomic-resolution microscope.The formed Bi’_(Te)antisite defects and enhanced{000 l}preferential orientation in BST are responsible for the increased carrier concentration and mobility,which leads to optimized electrical properties.The heterogeneous interface phases,along with antisite defects,favor the phonon scattering enhancement and lattice thermal conductivity suppression.The optimized composite sintered at 693 K exhibited a maximum ZT of 1.27 at 300 K.Furthermore,the well-controlled interfacial reaction has a slight impact on the magnetic properties of Gd and a high magnetic entropy change is retained in the composites.This work provides a universal approach to fabricating thermo-electro-magnetic materials with excellent MC and TE properties.

Evaluation and intelligent deployment of coal and coalbed methane coupling coordinated exploitation based on Bayesian network and cuckoo search

Coal and coalbed methane(CBM)coordinated exploitation is a key technology for the safe exploitation of both resources.However,existing studies lack the quantification and evaluation of the degree of coordination between coal mining and coalbed methane extraction.In this study,the concept of coal and coalbed methane coupling coordinated exploitation was proposed,and the corresponding evaluation model was established using the Bayesian principle.On this basis,the objective function of coal and coalbed methane coordinated exploitation deployment was established,and the optimal deployment was determined through a cuckoo search.The results show that clarifying the coupling coordinated level of coal and coalbed methane resource exploitation in coal mines is conducive to adjusting the deployment plan in advance.The case study results show that the evaluation and intelligent deployment method proposed in this paper can effectively evaluate the coupling coordinated level of coal and coalbed methane resource exploitation and intelligently optimize the deployment of coal mine operations.The optimization results demonstrate that the safe and efficient exploitation of coal and CBM resources is promoted,and coal mining and coalbed methane extraction processes show greater cooperation.The observations and findings of this study provide a critical reference for coal mine resource exploitation in the future.

Simulation of dilatancy-controlled gas migration processes in saturated bentonite using a coupled multiphase flow and elastoplastic H2 M model

Dilatancy-controlled gas flow in preferential pathways plays a key role in the safety analysis of radioactive waste repositories.This is particularly the case for bentonite,an often-preferred barrier material.Gas flow in preferential pathways is characterized by localization and spontaneous behavior,which is challenging to simulate in numerical models due to strong hydro-mechanical coupling.To analyze a laboratory experiment in the framework of the DECOVALEX-2023 project,this study introduced a new approach of combining continuous modelling methods with spatial material properties derived from material heterogeneities and experimental observations.The proposed model utilized hydro-mechanical spatial distributions,namely Young’s modulus and gas entry pressure,and elastoplasticity combined with a linear swelling model.A conceptual strain-dependent permeability approach simulated dilatancycontrolled gas flow based on hydro-mechanical coupling.To test the effectiveness of the presented approach,a gas injection test in a compacted,saturated bentonite sample was simulated using the opensource code OpenGeoSys 5.8 and compared with experimental observations.The presented methodology is capable of simulating localized gas flow in preferential pathways.The spatial distributions of Young’s modulus and gas entry pressure affect the swelling pressure,relative permeability and,in combination with the strain-dependent permeability model,also the intrinsic permeability.

Characterization of Rheum palmatum mitochondrial genome and comparative analysis among Caryophyllales species

Objective:This work aimed to report the first complete mitochondrial genome(mitogenome)of Rheum palmatum,summarize the features of Caryophyllales mitogenomes,and to reveal the potential of utilizing the mitogenomes of R.palmatum and other Caryophyllales species for inferring phylogenetic relationships and species identification.Methods:Both Illumina short reads and PacBio HiFi reads were utilized to obtain a complete mitogenome of R.palmatum.A variety of bioinformatics tools were employed to characterize the R.palmatum mitogenome,compare the reported mitogenomes in Caryophyllales and conduct phylogenetic analysis.Results:The mitogenome of R.palmatum was assembled into a single master circle of 302,993 bp,encoding 35 known protein-coding genes,18 transfer RNA genes,and three ribosome RNA genes.A total of 249 long repeats and 49 simple sequence repeats were identified in this mitogenome.The sizes of mitogenomes in Caryophyllales varied from 253 kb to 11.3 Mb.Among them,23 mitogenomes were circular molecules,one was linear,and one consisted of relaxed circles,linear molecules,and supercoiled DNA.Out of the total mitogenomes,11 were single-chromosome structure,whereas the remaining 14 were multi-chromosomal organizations.The phylogenetic analysis is consistent with both the Engler system(1964)and the Angiosperm Phylogeny Group III system.Conclusions:We obtained the first mitogenome of R.palmatum,which consists of a master circle.Mitogenomes in Caryophyllales have variable genome sizes and structures even within the same species.Circular molecules are still the dominant pattern in Caryophyllales.Single-chromosome mitogenomes account for nearly a half of all the mitogenomes in Caryophyllales,in contrast to previous studies.It is feasible to utilize mitochondrial genomes for inferring phylogenetic relationships and conducting species identification.

Co-adsorption and selective-adsorption of heavy metals and dyes from aqueous solution by bio-based humus/chitosan hydrogels

An eco-friendly adsorbent was prepared by reverse suspension crosslinking method to remove multiple pollutants from aqueous solution.Both raw materials,derived from humus(HS)and chitosan(CS),are biodegradable and low-cost natural biopolymers.After combining HS with CS,the adsorption capacity was significantly improved due to compensation effects between the two components.HS/CS exhibited the features of amphoteric adsorption through pH adjustment,enabling it to adsorb not only anionic pollutants(Methyl Orange(MO)and Cr(VI)),but also cationic ones(Methylene Blue(MB)and Pb(II)).The adsorption capacities were approximately 242 mg/g,69 mg/g,188 mg/g and 57 mg/g for MO,Cr(VI),MB and Pb(II),respectively.HS/CS showed a slight preference for MO in MO/Cr(VI)co-adsorption system,whereas strong selectivity for MB over Pb(II)in MB/Pb(II)system under acidic condition(pH<3.0).This selective behavior would allow for potential applications in separating MB/Pb(II)effluents and selectively recycling Pb(II)in acidic environment.The isothermal and kinetic adsorption behaviors followed Langmuir model and pseudo-second-order model,respectively.The density functional theory(DFT)confirmed that the interaction between metal ions and adsorbents was primarily attributed to chelation and electrostatic adsorption,owing to nitric and oxygenic functional groups.Whereas,the adsorption mechanisms for dyes were involved in electrostatic attraction,H-bond andπ-πbond,due to available hydrogen,oxygen,nitrogen atoms and aromatic groups on the surface of adsorbent and adsorbates.The adsorbent could be efficiently regenerated and retained over 90%of its adsorption capacity after five cycles,which has a potential for practical applications in water treatment.

Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional groups.There is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded transformations.In this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination sphere.Transmission electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the catalyst.The phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the activities.The results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-dichlorofluorescein.This process can be regulated through the methylation of the imidazole component at various positions.This work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

Erratum to:Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

Erratum to Nano Research,2024,17(6):4916−4923 https://doi.org/10.1007/s12274-024-6489-5 Labeling and statement of equal contribution of the authors Yuanxi Liu and Wenjie Xu were missed in the original article as well as the Electronic Supplementary Material.Superscript symbols of equal contribution“§”were added to both authors in the author list,and their contribution was stated as follows:“§Yuanxi Liu and Wenjie Xu contributed equally to this work.”

Genomic analysis of modern maize inbred lines reveals diversity and selective breeding effects

Dear Editor,Maize(Zea mays L.)is one of the most widely cultivated crops worldwide(Ranum et al.,2014),accounting for about 37.2%of the global cereal crop production.Maize production yield has increased over sevenfold since single-cross maize hybrids were deployed in the beginning of the last century(Andorf et al.,2019).

Exaptation of pectoral fins for olfaction in the spiny red gurnard(Chelidonichthys spinosus)through an ancient receptor

Dear Editor,Exaptation is defined as characters evolved for other usages(or for no function at all)and later“coopted”for their current role(Gould and Vrba,1982).Exaptation has occurred in many organisms,sometimes as an outcome of organ specialization for adaptation.This process is exemplified in the family Triglidae,commonly known as gurnards or sea robins.

Therapeutic effect in patients with coronary heart disease based on information analysis from Traditional Chinese Medicine four diagnostic methods

OBJECTIVE:To study information gained by Traditional Chinese Medicine(TCM)four diagnostic methods and characteristics of syndrome development before and after treatment in patients with coronary heart disease,and to probe into assessment indexes of therapeutic effects with distinctive TCM features.METHODS:Information from the four diagnostic methods before and after treatment in 100 patients with coronary heart disease was collected using the TCM interrogation scale,a pulse condition instrument,a tongue-face diagnosis instrument,anda voice diagnosis information collection system.Changes in the four diagnostic method results from before and after treatment were analyzed with frequency analysis and t-test methods.RESULTS:Before treatment,deficiency syndrome complicated with hyperactivity of pathogenic factors was most common.After treatment,deficiency syndrome was most common.This change from complex syndromes to single syndromes indicates disease and syndrome alleviation.Frequencies of symptoms gained by interrogation after treatment for syndrome of deficiency of heart-Qi,syndrome of deficiency of heart-Yin,and turbid phlegm syndrome were all less severe than those before treatment.Parameters of face color,color on all sub-regions of tongue,color of tongue fur,septic and greasy fur,and lip color after treatment all had significant changes.After treatment,part of the voice diagnosis parameters in the deficiency of heart-Yin and turbid phlegm syndromes had significant changes,but no significant changes were found in the deficiency of heart-Qi syndrome.CONCLUSION:Use of the TCM four diagnostic methods can provide an effective basis forTCM syndrome diagnosis,observation of development of state of illness,and evaluation of clinical therapeutic effects.

Bacterial outer membrane vesicles-based therapeutic platform eradicates triple-negative breast tumor by combinational photodynamic/chemo-/immunotherapy

Bacterial outer membrane vesicles(OMVs)are potent immuno-stimulating agents and have the potentials to be bioengineered as platforms for antitumor nanomedicine.In this study,OMVs are demonstrated as promising antitumor therapeutics.OMVs can lead to beneficial M2-to-M1 polarization of macrophages and induce pyroptosis to enhance antitumor immunity,but the therapeutic window of OMVs is narrow for its toxicity.We propose a bioengineering strategy to enhance the tumor-targeting ability of OMVs by macrophage-mediated delivery and improve the antitumor efficacy by co-loading of photosensitizer chlorin e6(Ce6)and chemotherapeutic drug doxorubicin(DOX)into OMVs as a therapeutic platform.We demonstrate that systemic injection of the DOX/Ce6-OMVs@M therapeutic platform,providing combinational photodynamic/chemo-/immunotherapy,eradicates triple-negative breast tumors in mice without side effects.Importantly,this strategy also effectively prevents tumor metastasis to the lung.This OMVs-based strategy with bioengineering may serve as a powerful therapeutic platform for a synergic antitumor therapy.

Monsoon boosted radiation of the endemic East Asian carps

Major historical events often trigger the rapid flourishing of a few lineages,which in turn shape established biodiversity patterns.How did this process occur and develop?This study provides a window into this issue.The endemic East Asian carps(EEAC)dominated the ichthyofauna of East Asia and exhibited a high degree of adaptation to monsoonal river-lake ecosystems.A series of evidence,including ecogeography,phylogenetics,and macroevolution,suggests that the EEAC is a lineage that arose with the East Asian monsoon and thrived intimately with subsequent monsoon activities.We further deduce the evolution of the EEAC and find that a range of historical events in the monsoon setting(e.g.,marine transgression and regression and glacial-interglacial cycle)have further reshaped the distribution patterns of EEAC’s members.Comparative genomics analyses reveal that introgressions during the initial period of EEAC radiation and innovations in the regulation of the brain and nervous system may have aided their adaptation to river-lake ecosystems in a monsoon setting,which boosted radiation.Overall,this study strengthens knowledge of the evolutionary patterns of freshwater fishes in East Asia and provides a model case for understanding the impact of major historical events on the evolution of biota.

Biomass-derived hard carbon microtubes with tunable apertures for high-performance sodium-ion batteries

Sodium-ion batteries(SIBs)are considered the most up-and-coming complements for large-scale energy storage devices due to the abundance and cheap sodium.However,due to the bigger radius,it is still a great challenge to develop anode materials with suitable space for the intercalation of sodium ions.Herein,we present hard carbon microtubes(HCTs)with tunable apertures derived from low-cost natural kapok fibers via a carbonization process for SIBs.The resulted HCTs feature with smaller surface area and shorter Na+diffusion path benefitting from their unique micro-nano structure.Most importantly,the wall thickness of HCTs could be regulated and controlled by the carbonization temperature.At a high temperature of 1,600℃,the carbonized HCTs possess the smallest wall thickness,which reduces the diffusion barrier of Na+and enhances the reversibility Na+storage.As a result,the 1600HCTs deliver a high initial Coulombic efficiency of 90%,good cycling stability(89.4%of capacity retention over 100 cycles at 100 mA·g^(−1)),and excellent rate capacity.This work not only charts a new path for preparing hard carbon materials with adequate ion channels and novel tubular micro-nano structures but also unravels the mechanism of hard carbon materials for sodium storage.

Pseudo-chromosome–length genome assembly for a deep-sea eel Ilyophis brunneus sheds light on the deep-sea adaptation

High hydrostatic pressure,low temperature,and scarce food supply are the major factors that limit the survival of vertebrates in extreme deep-sea environments.Here,we constructed a high-quality genome of the deep-sea Muddy arrowtooth eel(MAE,Ilyophis brunneus,captured below a depth of 3,500 m)by using Illumina,Pac Bio,and Hi-C sequencing.We compare it against those of shallow-water eel and other outgroups to explore the genetic basis that underlies the adaptive evolution to deep-sea biomes.The MAE genome was estimated to be 1.47 Gb and assembled into 14 pseudo-chromosomes.Phylogenetic analyses indicated that MAE diverged from its closely related shallow-sea species,European eel,~111.9 Mya and experienced a rapid evolution.The genome evolutionary analyses primarily revealed the following:(i)under high hydrostatic pressure,the positively selected gene TUBGCP3 and the expanded family MLC1 may improve the cytoskeleton stability;ACOX1 may enhance the fluidity of cell membrane and maintain transport activity;the expansion of ABCC12 gene family may enhance the integrity of DNA;(ii)positively selected HARS likely maintain the transcription ability at low temperatures;and(iii)energy metabolism under a food-limited environment may be increased by expanded and positively selected genes in AMPK and m TOR signaling pathways.

Halide Homogenization for High-Performance Blue Perovskite Electroluminescence

Metal halide perovskite light-emitting diodes(LEDs)have achieved great progress in recent years.However,bright and spectrally stable blue perovskite LED remains a significant challenge.Three-dimensional mixed-halide perovskites have potential to achieve high brightness electroluminescence,but their emission spectra are unstable as a result of halide phase separation.Here,we reveal that there is already heterogeneous distribution of halides in the as-deposited perovskite films,which can trace back to the nonuniform mixture of halides in the precursors.By simply introducing cationic surfactants to improve the homogeneity of the halides in the precursor solution,we can overcome the phase segregation issue and obtain spectrally stable single-phase blueemitting perovskites.We demonstrate efficient blue perovskite LEDs with high brightness,e.g.,luminous efficacy of 4.7,2.9,and 0.4 lmW^(-1) and luminance of over 37,000,9,300,and 1,300 cdm^(-2) for sky blue,blue,and deep blue with Commission Internationale de l’Eclairage(CIE)coordinates of(0.068,0.268),(0.091,0.165),and(0.129,0.061),respectively,suggesting real promise of perovskites for LED applications.

Multiple-quantum-well perovskite for hole-transport-layer-free light-emitting diodes

We demonstrate hole-transport-layer-free light-emitting diodes(LEDs) based on solution-processed multiple-quantum-well(MQW) perovskite. The MQW perovskite can self-assemble to a unique structure of vertically graded distribution with two-dimensional layered perovskite covered by three-dimensionallike perovskite at top, which can naturally form a barrier of electron transporting to the anode interface,thereby enhancing the charge capture efficiency. This leads to hole-transport-layer-free MQW perovskite LEDs reaching an external quantum efficiency(EQE) of 9.0% with emission peak at 528 nm, which is over6 times of LEDs based on three-dimensional perovskite with the same device structure, representing the record EQE of hole-transport-layer-free perovskite LED.

Vacancy manipulating of molybdenum carbide MXenes to enhance Faraday reaction for high performance lithium-ion batteries

“Intrinsic”strategies for manipulating the local electronic structure and coordination environment of defect-regulated materials can optimize electrochemical storage performance.Nevertheless,the structure–activity relationship between defects and charge storage is ambiguous,which may be revealed by constructing highly ordered vacancy structures.Herein,we demonstrate molybdenum carbide MXene nanosheets with customized in-plane chemical ordered vacancies(Mo_(1.33)CT_(x)),by utilizing selective etching strategies.Synchrotron-based X-ray characterizations reveal that Mo atoms in Mo1.33CTx show increased average valence of+4.44 compared with the control Mo_(2)CT_(x).Benefited from the introduced atomic active sites and high valence of Mo,Mo_(1.33)CT_(x)achieves an outstanding capacity of 603 mAh·g^(−1)at 0.2 A·g^(−1),superior to most original MXenes.Li+storage kinetics analysis and density functional theory(DFT)simulations show that this optimized performance ensues from the more charge compensation during charge–discharge process,which enhances Faraday reaction compared with pure Mo_(2)CT_(x).This vacancy manipulation provides an efficient way to realize MXene’s potential as promising electrodes.

Distinct and shared endothermic strategies in the heat producing tissues of tuna and other teleosts

Although most fishes are ectothermic,some,including tuna and billfish,achieve endothermy through specialized heat producing tissues that are modified muscles.How these heat producing tissues evolved,and whether they share convergent molecular mechanisms,remain unresolved.Here,we generated a high-quality genome from the mackerel tuna(Euthynnus affinis)and investigated the heat producing tissues of this fish by single-nucleus and bulk RNA sequencing.Compared with other teleosts,tuna-specific genetic variation is strongly associated with muscle differentiation.Single-nucleus RNA-seq revealed a high proportion of specific slow skeletal muscle cell subtypes in the heat producing tissues of tuna.Marker genes of this cell subtype are associated with the relative sliding of actin and myosin,suggesting that tuna endothermy is mainly based on shivering thermogenesis.In contrast,cross-species transcriptome analysis indicated that endothermy in billfish relies mainly on nonshivering thermogenesis.Nevertheless,the heat producing tissues of the different species do share some tissue-specific genes,including vascular-related and mitochondrial genes.Overall,although tunas and billfishes differ in their thermogenic strategies,they share similar expression patterns in some respects,highlighting the complexity of convergent evolution.